Bio


Dr. Carvalho is the Chief of Obstetric Anesthesiology and Maternal Health, Vice Chair of Faculty Development, and Professor in the Department of Anesthesiology, Perioperative and Pain Medicine, Stanford University Medical Center. He is the Past President of the Society of Obstetric Anesthesia and Perinatology (SOAP), and founder the SOAP Center of Excellence for Obstetric Anesthesia Care Designation. He has published extensively in the field of Obstetric Anesthesia with over 350 peer-reviewed articles, editorials, reviews, book chapters and commentaries. He has received several NIH, pharmaceutical and institutional grants, and won numerous research awards including three Best Research Papers at SOAP scientific meetings. Dr. Carvalho has won both the early and late-career Teacher of the Year awards at SOAP, and was voted Teacher of the Year at Stanford University’s Departments of Anesthesia. He has presented at over 220 regional, national and international meetings and visiting professorships. He serves/has served on numerous national medical society committees and medical journal editorial boards, and as an advisor/consultant to the World Health Organization. His clinical and translational research and scholarly activities cover cesarean and labor analgesia, perinatal pharmacology and immunology, obstetric hemorrhage, and postpartum recovery.

Clinical Focus


  • Anesthesia
  • Anesthesia, Obstetrical
  • Anesthesia, Regional

Academic Appointments


Administrative Appointments


  • Chief, Division of Obstetric Anesthesia (2013 - Present)

Professional Education


  • Board Certification: American Board of Anesthesiology, Anesthesia (2014)
  • Fellowship, Stanford University, Obstetric Anesthesia (2002)
  • Residency: Southwest School of Anesthesia (2001) England
  • Internship: Groote Schuur Hospital (1995) South Africa
  • Medical Education: University of Witwatersrand (1994) South Africa

Current Research and Scholarly Interests


I have completed research in a number of important areas in obstetric anesthesia including: optimizing neuraxial techniques for labor and cesarean analgesia; predicting individual labor and cesarean pain and analgesic needs; evaluating pregnancy-induced and hormonal changes in pain perception; determining the role of cytokines and other biochemical mediators in incisional wounds; evaluating local anesthetic potency and anesthetic requirements during labor and cesarean delivery; determining epidural and spinal opioid applications and the role of long-acting neuraxial opioids in obstetric pain management; investigating peripartum hemostatic and coagulation changes; conducting cost-analyses of various obstetric anesthesia practices; optimizing the management of maternal cardiac arrest and other obstetrical emergencies; determining patient attitudes and ethnic preferences towards obstetric analgesia; determining the efficacy of peripheral wound drug administration; and pharmacokinetics/pharmacodynamics of drugs administered to pregnant women. My current area of research focus is in developing novel ways of improving post-cesarean and peripartum labor pain management, and developing detailed pharmacokinetics/pharmacodynamics models of key antenatal medications.

Clinical Trials


  • Calcium Chloride for Prevention of Uterine Atony During Cesarean Not Recruiting

    In this pilot study, investigators will administer calcium chloride or placebo to pregnant women undergoing Cesarean delivery who have been identified as high risk for hemorrhage due to poor uterine muscle contraction, or atony. They will assess whether a single dose of calcium given immediately after the delivery of the fetus decreases the incidence of uterine atony and bleeding for the mother. The pharmacokinetics of calcium chloride in pregnant women will also be established. Data from this pilot study of 40 patients will be used to determine sample size and appropriateness of a larger randomized clinical trial.

    Stanford is currently not accepting patients for this trial. For more information, please contact Brendan Carvalho, MBBCh, FRCA, 650-861-8607.

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  • Oxytocin Pharmacokinetics and Pharmacodynamics Not Recruiting

    Oxytocin is the first-line drug to promote contraction of the uterus and prevent atony immediately after delivery. Nonetheless, unpredictable uterine atony refractory to oxytocin affects roughly 250,000 parturients annually in the U.S. and rates are increasing. This two-part study will measure the action of oxytocin at cesarean delivery. The first part will measure the pharmacokinetics of a single intravenous (IV) dose of deuterium-labeled oxytocin. The second part will measure the pharmacodynamics of all plasma oxytocin to see how concentrations correspond to the contractile effect on the uterus. After delivery of the fetus, study subjects will receive a bolus of IV deuterated oxytocin followed by an unlabeled oxytocin infusion. Venous blood samples drawn at multiple time points (within 1 hour after delivery) will be analyzed for plasma concentrations of labeled and unlabeled (endogenous + exogenous infused) oxytocin over time. Plasma concentrations will be compared with 0-10 uterine tone scores measuring uterine contraction strength, to describe the concentration-effect relationship. The goal of this study is to define both the pharmacokinetics and pharmacodynamics of oxytocin in parturients to help identify the cause(s) of failed first-line oxytocin therapy.

    Stanford is currently not accepting patients for this trial.

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  • Pharmacokinetic (PK) and Pharmacodynamic (PD) Modeling of Ampicillin and Gentamicin in Peripartum Patients Not Recruiting

    This study proposes to compare the metabolism of Ampicillin and Gentamicin by pregnant women to that of non-pregnant women; the placental transfer over time; and the subsequent metabolism of the transferred drug(s) in the neonate.

    Stanford is currently not accepting patients for this trial. For more information, please contact Brendan Carvalho, MBBCh, 650-861-8607.

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  • Virtual Reality Compared to Nitrous Oxide for Labor Analgesia Not Recruiting

    The purpose of this study is to determine if non-invasive distracting devices (Virtual Reality headsets) are non-inferior to conventional therapy (nitrous oxide) for addressing maternal needs during labor who desire non-epidural pain relief.

    Stanford is currently not accepting patients for this trial. For more information, please contact Brendan Carvalho, 650-222-7967.

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2024-25 Courses


All Publications


  • Comparative efficacy of intravenous treatments for perioperative shivering in patients undergoing caesarean delivery under neuraxial anaesthesia: A systematic review and Bayesian network meta-analysis of randomised-controlled trials. Journal of clinical anesthesia Ferrea, G., Monks, D. T., Singh, P. M., Fedoruk, K., Singh, N. P., Blake, L., Carvalho, B., Sultan, P. 2024; 100: 111680

    Abstract

    Shivering affects 52 % of patients undergoing caesarean delivery under neuraxial anaesthesia. Despite extensive research focused on its prevention, there is still no consensus regarding optimal pharmacological treatment. This systematic review and network meta-analysis aims to compare available intravenous treatments of perioperative shivering in patients undergoing caesarean delivery under neuraxial anaesthesia.We searched seven databases (PubMed MEDLINE, Scopus, Web of Science, Embase, LILACS, Cochrane CRCT and clinicaltrials.gov) for randomised controlled trials comparing intravenous treatments of perioperative shivering during caesarean delivery and performed a Bayesian model network meta-analysis. We assessed study quality using the Cochrane risk of bias assessment tool. The primary outcome evaluated in this meta-analysis was shivering control (cessation or significant reduction in intensity), and secondary outcomes included time to shivering control, shivering recurrence, and incidence of maternal nausea.Twenty randomised controlled trials, with a total of 1983 patients, were included in this analysis. Network estimates of odds ratios (OR [95 % Credible Interval]) of effective treatment of shivering compared with saline were: dexmedetomidine (38.1 [14.2 to 111.5]), tramadol (33.6 [15.1 to 81.8]), nalbuphine (26.2 [10.8 to 80.2]), meperidine (20.9 [6.2 to 73.1]), ondansetron (6.6 [2.2 to 23.2]), and clonidine (3.2 [0.6 to 14.9]). The rank order of interventions by surface area under the cumulative ranking curve scores (in parenthesis) for shivering control was dexmedetomidine (0.87) > tramadol (0.85) > nalbuphine (0.74) > meperidine (0.66) > ondansetron (0.41) > clonidine (0.3) > amitriptyline (0.03). Dexmedetomidine was also the top-ranked intervention for time to shivering control, shivering recurrence and maternal nausea. We judged the certainty in the evidence to be moderate for dexmedetomidine and nalbuphine, and low for all other interventions.This network meta-analysis identified four effective intravenous treatments for shivering in patients undergoing caesarean delivery under neuraxial anaesthesia: dexmedetomidine, tramadol, nalbuphine and meperidine. Dexmedetomidine was the top-ranked intervention for all outcomes.

    View details for DOI 10.1016/j.jclinane.2024.111680

    View details for PubMedID 39608094

  • Consensus Statement on Pain Management for Pregnant Patients with Opioid-Use Disorder from the Society for Obstetric Anesthesia and Perinatology, Society for Maternal-Fetal Medicine, and American Society of Regional Anesthesia and Pain Medicine. Anesthesia and analgesia Lim, G., Carvalho, B., George, R. B., Bateman, B. T., Brummett, C. M., Ip, V. H., Landau, R., Osmundson, S. S., Raymond, B., Richebe, P., Soens, M., Terplan, M. 2024

    Abstract

    Pain management in pregnant and postpartum people with an opioid-use disorder (OUD) requires a balance between risks associated with opioid tolerance, including withdrawal or return to opioid use, considerations around social needs of the maternal-infant dyad, and the provision of adequate pain relief for the birth episode that is often characterized as the worst pain a person will experience in their lifetime. This multidisciplinary consensus statement between the Society for Obstetric Anesthesia and Perinatology (SOAP), Society for Maternal-Fetal Medicine (SMFM), and American Society of Regional Anesthesia and Pain Medicine (ASRA) provides a framework for pain management in obstetric patients with OUD. The purpose of this consensus statement is to provide practical and evidence-based recommendations and is targeted to health care providers in obstetrics and anesthesiology. The statement is focused on prenatal optimization of pain management, labor analgesia, and postvaginal delivery pain management, and postcesarean delivery pain management. Topics include a discussion of nonpharmacologic and pharmacologic options for pain management, medication management for OUD (eg, buprenorphine, methadone), considerations regarding urine drug testing, and other social aspects of care for maternal-infant dyads, as well as a review of current practices. The authors provide evidence-based recommendations to optimize pain management while reducing risks and complications associated with OUD in the peripartum period. Ultimately, this multidisciplinary consensus statement provides practical and concise clinical guidance to optimize pain management for people with OUD in the context of pregnancy to improve maternal and perinatal outcomes.

    View details for DOI 10.1213/ANE.0000000000007237

    View details for PubMedID 39504271

  • A Survey of Obstetric Anaesthesia Services and Practices in the United Kingdom. Cureus O'Carroll, J., Zucco, L., Warwick, E., Arbane, G., Moonesinghe, R., El-Boghdadly, K., Guo, N., Carvalho, B., Sultan, P. 2024; 16 (10): e70851

    Abstract

    Background Variability in obstetric anaesthetia practice and care delivered within the UK is under-explored. The ObsQoR study explored structures, processes, and outcomes of obstetric anaesthesia in 107 hospitals within the UK's National Health Service, and the results of the hospital-level survey are reported here. Methods Hospitals were surveyed to assess obstetric anaesthesia provision, practice, and care delivery. Questions explored staffing, service provision and training, facilities present, clinical practices, outcome measurement, and key indicators of quality in obstetric anaesthesia. Results We received responses from 106 participating hospitals, representing 69% of all UK obstetric units. One hundred (94%) hospitals had a dedicated consultant obstetric anaesthetist within working hours, with 27 (25%) of hospitals' duty anaesthetists having additional clinical responsibilities outside the care of obstetric patients outside of working hours. Around 102 hospitals (98%) offer multidisciplinary team training, of which 95 (93%) use a simulation-based method. Dedicated high-risk antenatal clinics were present in 50 (47%) hospitals. The majority of hospitals provide written patient information in multiple languages for discussing obstetric anaesthesia options (77, 82%). Seventy-three hospitals (69%) use point-of-care testing to estimate haemoglobin concentration. Labour epidural analgesia is most commonly delivered via patient-controlled epidural analgesia in 80 (76%) hospitals, and the incidence of post-dural puncture headaches was recorded by 80 (76%) hospitals. Conclusions These results demonstrate variation in the provision of staffing, facilities, clinical practices, and outcome measurements across the UK. To deliver safe and equitable care across the UK, there needs to be standardisation of anaesthetic peripartum care based on national recommendations and the benchmarking and measurement of appropriate markers of quality.

    View details for DOI 10.7759/cureus.70851

    View details for PubMedID 39493055

    View details for PubMedCentralID PMC11531797

  • The evaluation of the performance of ChatGPT in the management of labor analgesia. Journal of clinical anesthesia Ismaiel, N., Nguyen, T. P., Guo, N., Carvalho, B., Sultan, P. 2024; 98: 111582

    Abstract

    ChatGPT4 is a leading large language model (LLM) chatbot released by OpenAI in 2023. ChatGPT4 can respond to free-text queries, answer questions and make suggestions regarding virtually any topic. ChatGPT4 has successfully answered anesthesia and even obstetric anesthesia knowledge-based questions with reasonable accuracy. However, ChatGPT4 has yet to be challenged in obstetric anesthesia clinical decision-making.In this study, we evaluated the performance of ChatGPT4 in the management of clinical labor analgesia scenarios compared to expert obstetric anesthesiologists.Eight clinical questions with progressively increasing medical complexity were posed to ChatGPT4.The ChatGPT4 responses were rated by seven expert obstetric anesthesiologists based on safety, accuracy and completeness of each response using a five-point Likert rating scale.ChatGPT4 was deemed safe in 73% of responses to the presented obstetric anesthesia clinical scenarios (27% of responses were deemed unsafe). None of the ChatGPT4 responses were unanimously deemed to be safe by all seven expert obstetric anesthesiologists. Moreover, ChatGPT4 responses were overall partly accurate (score 4 out of 5) and somewhat incomplete (score 3.5 out of 5).In summary, approximately one quarter of all responses by ChatGPT4 were deemed unsafe by expert obstetric anesthesiologists. These findings may suggest the need for more fine-tuning and training of LLMs such as ChatGPT4 specifically for clinical decision making in obstetric anesthesia or other specialized medical fields. These LLMs may come to play an important future role in assisting obstetric anesthesiologists in clinical decision making and enhancing overall patient care.

    View details for DOI 10.1016/j.jclinane.2024.111582

    View details for PubMedID 39167880

  • Comparison of artificial intelligence large language model chatbots in answering frequently asked questions in anaesthesia. BJA open Nguyen, T. P., Carvalho, B., Sukhdeo, H., Joudi, K., Guo, N., Chen, M., Wolpaw, J. T., Kiefer, J. J., Byrne, M., Jamroz, T., Mootz, A. A., Reale, S. C., Zou, J., Sultan, P. 2024; 10: 100280

    Abstract

    Patients are increasingly using artificial intelligence (AI) chatbots to seek answers to medical queries.Ten frequently asked questions in anaesthesia were posed to three AI chatbots: ChatGPT4 (OpenAI), Bard (Google), and Bing Chat (Microsoft). Each chatbot's answers were evaluated in a randomised, blinded order by five residency programme directors from 15 medical institutions in the USA. Three medical content quality categories (accuracy, comprehensiveness, safety) and three communication quality categories (understandability, empathy/respect, and ethics) were scored between 1 and 5 (1 representing worst, 5 representing best).ChatGPT4 and Bard outperformed Bing Chat (median [inter-quartile range] scores: 4 [3-4], 4 [3-4], and 3 [2-4], respectively; P<0.001 with all metrics combined). All AI chatbots performed poorly in accuracy (score of ≥4 by 58%, 48%, and 36% of experts for ChatGPT4, Bard, and Bing Chat, respectively), comprehensiveness (score ≥4 by 42%, 30%, and 12% of experts for ChatGPT4, Bard, and Bing Chat, respectively), and safety (score ≥4 by 50%, 40%, and 28% of experts for ChatGPT4, Bard, and Bing Chat, respectively). Notably, answers from ChatGPT4, Bard, and Bing Chat differed statistically in comprehensiveness (ChatGPT4, 3 [2-4] vs Bing Chat, 2 [2-3], P<0.001; and Bard 3 [2-4] vs Bing Chat, 2 [2-3], P=0.002). All large language model chatbots performed well with no statistical difference for understandability (P=0.24), empathy (P=0.032), and ethics (P=0.465).In answering anaesthesia patient frequently asked questions, the chatbots perform well on communication metrics but are suboptimal for medical content metrics. Overall, ChatGPT4 and Bard were comparable to each other, both outperforming Bing Chat.

    View details for DOI 10.1016/j.bjao.2024.100280

    View details for PubMedID 38764485

    View details for PubMedCentralID PMC11099318

  • In Response. Anesthesia and analgesia Mootz, A. A., Carvalho, B., Sultan, P., Nguyen, T. P., Reale, S. C. 2024; 138 (6): e37-e38

    View details for DOI 10.1213/ANE.0000000000006979

    View details for PubMedID 38771606

  • Associations between anxiety, sleep, and blood pressure parameters in pregnancy: a prospective pilot cohort study. BMC pregnancy and childbirth Miller, H. E., Simpson, S. L., Hurtado, J., Boncompagni, A., Chueh, J., Shu, C. H., Barwick, F., Leonard, S. A., Carvalho, B., Sultan, P., Aghaeepour, N., Druzin, M., Panelli, D. M. 2024; 24 (1): 366

    Abstract

    The potential effect modification of sleep on the relationship between anxiety and elevated blood pressure (BP) in pregnancy is understudied. We evaluated the relationship between anxiety, insomnia, and short sleep duration, as well as any interaction effects between these variables, on BP during pregnancy.This was a prospective pilot cohort of pregnant people between 23 to 36 weeks' gestation at a single institution between 2021 and 2022. Standardized questionnaires were used to measure clinical insomnia and anxiety. Objective sleep duration was measured using a wrist-worn actigraphy device. Primary outcomes were systolic (SBP), diastolic (DBP), and mean (MAP) non-invasive BP measurements. Separate sequential multivariable linear regression models fit with generalized estimating equations (GEE) were used to separately assess associations between anxiety (independent variable) and each BP parameter (dependent variables), after adjusting for potential confounders (Model 1). Additional analyses were conducted adding insomnia and the interaction between anxiety and insomnia as independent variables (Model 2), and adding short sleep duration and the interaction between anxiety and short sleep duration as independent variables (Model 3), to evaluate any moderating effects on BP parameters.Among the 60 participants who completed the study, 15 (25%) screened positive for anxiety, 11 (18%) had subjective insomnia, and 34 (59%) had objective short sleep duration. In Model 1, increased anxiety was not associated with increases in any BP parameters. When subjective insomnia was included in Model 2, increased DBP and MAP was significantly associated with anxiety (DBP: β 6.1, p = 0.01, MAP: β 6.2 p < 0.01). When short sleep was included in Model 3, all BP parameters were significantly associated with anxiety (SBP: β 9.6, p = 0.01, DBP: β 8.1, p < 0.001, and MAP: β 8.8, p < 0.001). No moderating effects were detected between insomnia and anxiety (p interactions: SBP 0.80, DBP 0.60, MAP 0.32) or between short sleep duration and anxiety (p interactions: SBP 0.12, DBP 0.24, MAP 0.13) on BP.When including either subjective insomnia or objective short sleep duration, pregnant people with anxiety had 5.1-9.6 mmHg higher SBP, 6.1-8.1 mmHg higher DBP, and 6.2-8.8 mmHg higher MAP than people without anxiety.

    View details for DOI 10.1186/s12884-024-06540-w

    View details for PubMedID 38750438

    View details for PubMedCentralID 2941423

  • Strategies for optimising early detection and obstetric first response management of postpartum haemorrhage at caesarean birth: a modified Delphi-based international expert consensus. BMJ open Pingray, V., Williams, C. R., Al-Beity, F. M., Abalos, E., Arulkumaran, S., Blumenfeld, A., Carvalho, B., Deneux-Tharaux, C., Downe, S., Dumont, A., Escobar, M. F., Evans, C., Fawcus, S., Galadanci, H. S., Hoang, D. T., Hofmeyr, G. J., Homer, C., Lewis, A. G., Liabsuetrakul, T., Lumbiganon, P., Main, E. K., Maua, J., Muriithi, F. G., Nabhan, A. F., Nunes, I., Ortega, V., Phan, T. N., Qureshi, Z. P., Sosa, C., Varallo, J., Weeks, A. D., Widmer, M., Oladapo, O. T., Gallos, I., Coomarasamy, A., Miller, S., Althabe, F. 2024; 14 (5): e079713

    Abstract

    There are no globally agreed on strategies on early detection and first response management of postpartum haemorrhage (PPH) during and after caesarean birth. Our study aimed to develop an international expert's consensus on evidence-based approaches for early detection and obstetric first response management of PPH intraoperatively and postoperatively in caesarean birth.Systematic review and three-stage modified Delphi expert consensus.International.Panel of 22 global experts in PPH with diverse backgrounds, and gender, professional and geographic balance.Agreement or disagreement on strategies for early detection and first response management of PPH at caesarean birth.Experts agreed that the same PPH definition should apply to both vaginal and caesarean birth. For the intraoperative phase, the experts agreed that early detection should be accomplished via quantitative blood loss measurement, complemented by monitoring the woman's haemodynamic status; and that first response should be triggered once the woman loses at least 500 mL of blood with continued bleeding or when she exhibits clinical signs of haemodynamic instability, whichever occurs first. For the first response, experts agreed on immediate administration of uterotonics and tranexamic acid, examination to determine aetiology and rapid initiation of cause-specific responses. In the postoperative phase, the experts agreed that caesarean birth-related PPH should be detected primarily via frequently monitoring the woman's haemodynamic status and clinical signs and symptoms of internal bleeding, supplemented by cumulative blood loss assessment performed quantitatively or by visual estimation. Postoperative first response was determined to require an individualised approach.These agreed on proposed approaches could help improve the detection of PPH in the intraoperative and postoperative phases of caesarean birth and the first response management of intraoperative PPH. Determining how best to implement these strategies is a critical next step.

    View details for DOI 10.1136/bmjopen-2023-079713

    View details for PubMedID 38719306

  • Liposomal Bupivacaine for Abdominal Fascial Plane Blocks: No Evidence or Lack of Relevant Evidence? Anesthesiology Habib, A. S., Gadsden, J., Carvalho, B. 2024; 140 (5): 871-873

    View details for DOI 10.1097/ALN.0000000000004933

    View details for PubMedID 38592357

  • Evaluation of Sleep in Pregnant Inpatients Compared With Outpatients. Obstetrics and gynecology Panelli, D. M., Miller, H. E., Simpson, S. L., Hurtado, J., Shu, C. H., Boncompagni, A. C., Chueh, J., Barwick, F., Carvalho, B., Sultan, P., Aghaeepour, N., Druzin, M. L. 2024

    Abstract

    To evaluate whether antepartum hospitalization was associated with differences in sleep duration or disrupted sleep patterns.This was a prospective cohort study with enrollment of pregnant people aged 18-55 years with singleton gestations at 16 weeks of gestation or more between 2021 and 2022. Each enrolled antepartum patient was matched by gestational age to outpatients recruited from obstetric clinics at the same institution. Participants responded to the ISI (Insomnia Severity Index) and wore actigraph accelerometer watches for up to 7 days. The primary outcome was total sleep duration per 24 hours. Secondary outcomes included sleep efficiency (time asleep/time in bed), ISI score, clinical insomnia (ISI score higher than 15), short sleep duration (less than 300 minutes/24 hours), wakefulness after sleep onset, number of awakenings, and sleep fragmentation index. Outcomes were evaluated with multivariable generalized estimating equations adjusted for body mass index (BMI), sleep aid use, and insurance type, accounting for gestational age correlations. An interaction term assessed the joint effects of time and inpatient status.Overall 58 participants were included: 18 inpatients and 40 outpatients. Inpatients had significantly lower total sleep duration than outpatients (mean 4.4 hours [SD 1.6 hours] inpatient vs 5.2 hours [SD 1.5 hours] outpatient, adjusted β=-1.1, 95% CI, -1.8 to -0.3, P=.01). Awakenings (10.1 inpatient vs 13.8, P=.01) and wakefulness after sleep onset (28.3 inpatient vs 35.5 outpatient, P=.03) were lower among inpatients. There were no differences in the other sleep outcomes, and no interaction was detected for time in the study and inpatient status. Inpatients were more likely to use sleep aids (39.9% vs 12.5%, P=.03).Hospitalized pregnant patients slept about 1 hour/day less than outpatients. Fewer awakenings and reduced wakefulness after sleep onset among inpatients may reflect increased use of sleep aids in hospitalized patients.

    View details for DOI 10.1097/AOG.0000000000005591

    View details for PubMedID 38663016

  • Physical activity among pregnant inpatients and outpatients and associations with anxiety. European journal of obstetrics, gynecology, and reproductive biology Panelli, D. M., Miller, H. E., Simpson, S. L., Hurtado, J., Shu, C. H., Boncompagni, A. C., Chueh, J., Carvalho, B., Sultan, P., Aghaeepour, N., Druzin, M. L. 2024; 297: 8-14

    Abstract

    Physical activity is linked to lower anxiety, but little is known about the association during pregnancy. This is especially important for antepartum inpatients, who are known to have increased anxiety yet may not be able to achieve target levels of physical activity during hospitalization. We compared physical activity metrics between pregnant inpatients and outpatients and explored correlations with anxiety.This was a prospective cohort between 2021 and 2022 of pregnant people aged 18-55 years carrying singleton gestations ≥ 16 weeks. Three exposure groups were matched for gestational age: 1) outpatients from general obstetric clinics; 2) outpatients from high-risk Maternal-Fetal Medicine obstetric clinics; and 3) antepartum inpatients. Participants wore Actigraph GT9X Link accelerometer watches for up to 7 days to measure physical activity. The primary outcome was mean daily step count. Secondary outcomes were metabolic equivalent tasks (METs), hourly kilocalories (kcals), moderate to vigorous physical activity (MVPA) bursts, and anxiety (State-Trait Anxiety Inventory [STAI]). Step counts were compared using multivariable generalized estimating equations adjusting for maternal age, body-mass index, and insurance type as a socioeconomic construct, accounting for within-group clustering by gestational age. Spearman correlations were used to correlate anxiety scores with step counts.58 participants were analyzed. Compared to outpatients, inpatients had significantly lower mean daily steps (primary outcome, adjusted beta -2185, 95 % confidence interval [CI] -3146, -1224, p < 0.01), METs (adjusted beta -0.18, 95 % CI -0.23, -0.13, p < 0.01), MVPAs (adjusted beta -38.2, 95 % CI -52.3, -24.1, p < 0.01), and kcals (adjusted beta -222.9, 95 % CI -438.0, -7.8, p = 0.04). Over the course of the week, steps progressively decreased for inpatients (p-interaction 0.01) but not for either of the outpatient groups. Among the entire cohort, lower step counts correlated with higher anxiety scores (r = 0.30, p = 0.02).We present antenatal population norms and variance for step counts, metabolic equivalent tasks, moderate to vigorous physical activity bursts, and kcals, as well as correlations with anxiety. Antepartum inpatients had significantly lower physical activity than outpatients, and lower step counts correlated with higher anxiety levels. These results highlight the need for physical activity interventions, particularly for hospitalized pregnant people.

    View details for DOI 10.1016/j.ejogrb.2024.03.033

    View details for PubMedID 38554481

  • Continuous wound infusion catheter as part of a multimodal analgesia regimen for post-Caesarean delivery pain: a quality improvement impact study. BJA open Fowler, C., Stockert, E., Hoang, D., Guo, N., Riley, E., Sultan, P., Carvalho, B. 2024; 9: 100242

    Abstract

    The role of continuous wound infusion catheters as part of a multimodal analgesia strategy after Caesarean delivery is unclear. We introduced continuous wound infusion catheters to our multimodal analgesia regimen to evaluate the impact on analgesic outcomes after Caesarean delivery.After institutional review board (IRB) approval, a 4-month practice change was instituted as a quality improvement initiative. In addition to multimodal analgesia, continuous wound infusion catheters for up to 3 days were offered on alternate weeks for all women undergoing Caesarean deliveries. The primary outcome was postoperative in-hospital opioid consumption. Secondary outcomes were static and dynamic pain scores at 24 and 72 h, time until first analgesic request, opioid-related side-effects, length of stay, satisfaction (0-100%), and continuous wound infusion catheter-related complications.All women scheduled for Caesarean delivery (n=139) in the 4-month period were included in the analysis, with 70 women receiving continuous wound infusion catheters, and 69 in the control group. Opioid consumption (continuous wound infusion catheter group 11.3 [7.5-61.9] mg morphine equivalents vs control group 30.0 [11.3-48.8] mg morphine equivalents), pain scores (except 24 h resting pain scores which were higher in the control group 2 [1-3] vs 1.5 [0-3] in the continous wound infusion catheters group; P=0.05), side-effects, length of stay, and complications were similar between groups. Satisfaction scores at 24 h were higher with continuous wound infusion catheters (100% [91-100%] vs 90% [86-100%]; P=0.003) with no differences at 72 h. One patient demonstrated symptoms of systemic local anaesthetic toxicity which resolved without significant harm.The addition of continuous wound infusion catheters to a multimodal analgesia regimen for post-Caesarean delivery pain management demonstrated minimal clinically significant analgesic benefits. Future studies are needed to explore the use of continuous wound infusion catheters in populations that may benefit most from this intervention.

    View details for DOI 10.1016/j.bjao.2023.100242

    View details for PubMedID 38179106

    View details for PubMedCentralID PMC10761342

  • Ethnicity, socio-economic deprivation and postpartum outcomes following caesarean delivery: a multicentre cohort study. Anaesthesia O'Carroll, J. E., Zucco, L., Warwick, E., Radcliffe, G., Moonesinghe, S. R., El-Boghdadly, K., Guo, N., Carvalho, B., Sultan, P. 2024

    Abstract

    Disparities relating to postpartum recovery outcomes in different socio-economic and racial ethnic groups are underexplored. We conducted a planned analysis of a large prospective caesarean delivery cohort to explore the relationship between ethnicity, socio-economic status and postpartum recovery. Eligible patients were enrolled and baseline demographic, obstetric and medical history data were collected 18 h and 30 h following delivery. Patients completed postpartum quality of life and recovery measures in person on day 1 (EuroQoL EQ-5D-5L, including global health visual analogue scale; Obstetric Quality of Recovery-10 item score; and pain scores) and by telephone between day 28 and day 32 postpartum (EQ-5D-5L and pain scores). Socio-economic group was determined according to the Index of Multiple Deprivation quintile of each patient's usual place of residence. Data from 1000 patients who underwent caesarean delivery were included. There were more patients of Asian, Black and mixed ethnicity in the more deprived quintiles. Patients of White ethnicities had shorter postpartum duration of hospital stay compared with patients of Asian and Black ethnicities (35 (28-56 [18-513]) h vs. 44 (31-71 [19-465]) h vs. 49 (33-75 [23-189]) h, respectively. In adjusted models at day 30, patients of Asian ethnicity had a significantly greater risk of moderate to severe pain (numerical rating scale ≥ 4) at rest and on movement (odds ratio (95%CI) 2.42 (1.24-4.74) and 2.32 (1.40-3.87)), respectively). There were no differences in readmission rates or incidence of complications between groups. Patients from White ethnic backgrounds experience shorter postpartum duration of stay compared with patients from Asian and Black ethnic groups. Ethnic background impacts pain scores and recovery at day 1 postpartum and following hospital discharge, even after adjusting for socio-economic group. Further work is required to understand the underlying factors driving differences in pain and recovery and to develop strategies to reduce disparities in obstetric patients.

    View details for DOI 10.1111/anae.16241

    View details for PubMedID 38359531

  • A Cost and Waste-Savings Comparison Between Single-Use and Reusable Pulse Oximetry Sensors Across US Operating Rooms. Anesthesia and analgesia Stockert, E. W., Carvalho, B., Sun, E. C. 2024

    Abstract

    BACKGROUND: Operating room (OR) expenditures and waste generation are a priority, with several professional societies recommending the use of reprocessed or reusable equipment where feasible. The aim of this analysis was to compare single-use pulse oximetry sensor stickers ("single-use stickers") versus reusable pulse oximetry sensor clips ("reusable clips") in terms of annual cost savings and waste generation across all ORs nationally.METHODS: This study did not involve patient data or research on human subjects. As such, it did not meet the requirements for institutional review board approval. An economic model was used to compare the relative costs and waste generation from using single-use stickers versus reusable clips. This model took into account: (1) the relative prices of single-use stickers and reusable clips, (2) the number of surgeries and ORs nationwide, (3) the workload burden of cleaning the reusable clips, and (4) the costs of capital for single-use stickers and reusable clips. In addition, we also estimated differences in waste production based on the raw weight plus unit packaging of single-use stickers and reusable clips that would be disposed of over the course of the year, without any recycling interventions. Estimated savings were rounded to the nearest $0.1 million.RESULTS: The national net annual savings of transitioning from single-use stickers to reusable clips in all ORs ranged from $510.5 million (conservative state) to $519.3 million (favorable state). Variability in savings estimates is driven by scenario planning for replacement rate of reusable clips, workload burden of cleaning (ranging from an additional expense of $618k versus a cost savings of $309k), and cost of capital-interest gained on investment of capital that is freed up by the monetary savings of a transition to reusable clips contributes between $541k (low-interest rates of 2.85%) and $1.3 million (high-interest rates of 7.08%). The annual waste that could be diverted from landfill by transitioning to reusable clips was found to be between 587 tons (conservative state) up to 589 tons (favorable state). If institutions need to purchase new vendor monitors or cables to make the transition, that may increase the 1-time capital disbursement.CONCLUSIONS: Using reusable clips versus single-use stickers across all ORs nationally would result in appreciable annual cost savings and waste generation reduction impact. As both single-use stickers and reusable clips are equally accurate and reliable, this cost and waste savings could be instituted without a compromise in clinical care.

    View details for DOI 10.1213/ANE.0000000000006778

    View details for PubMedID 38195082

  • The Accuracy of ChatGPT-Generated Responses in Answering Commonly Asked Patient Questions About Labor Epidurals: A Survey-Based Study. Anesthesia and analgesia Mootz, A. A., Carvalho, B., Sultan, P., Nguyen, T. P., Reale, S. C. 2024

    View details for DOI 10.1213/ANE.0000000000006801

    View details for PubMedID 38180897

  • A retrospective cohort study of the anesthetic management of postpartum tubal ligation. International journal of obstetric anesthesia Ansari, J., Sheikh, M., Riley, E., Guo, N., Traynor, A., Carvalho, B. 2024: 103974

    Abstract

    Neuraxial anesthesia with reactivation of a labor epidural catheter is commonly utilized for postpartum tubal ligations (PPTL), although the optimal anesthetic approach is unknown. We assessed institutional anesthesia practices for PPTL, and evaluated the failure rates of reactivation of labor epidural catheters, de novo spinal anesthesia, and spinal anesthesia after failed blocks.We conducted a single-center retrospective cohort analysis of 300 consecutive patients who underwent a PPTL and 100 having spinal anesthesia for cesarean delivery. Anesthetic management data (existing labor epidural catheter reactivation, de novo spinal anesthesia or general anesthesia) were collected from electronic medical records. Anesthetic block failure rates were determined for each anesthetic technique.The failure rate was 15% for de novo spinal anesthesia and 23% after failed reactivation of a labor epidural catheter or spinal anesthesia. The epidural catheter reactivation failure rate was 35%. The failure rate of spinal anesthesia for cesarean delivery was 4%. Drug dosage, epidural catheter use in labor, time since epidural catheter placement or delivery, labor neuraxial technique (combined spinal-epidural, epidural), supplemental top-up doses during labor, and anesthesiologist experience did not predict neuraxial anesthesia failures.Our analysis revealed an unexpectedly high neuraxial anesthesia failure rate even when de novo spinal anesthesia was used for PPTL. The results are consistent with other institutions' recent findings, and are higher than spinal anesthesia failure rates associated with cesarean delivery. Further studies are required to determine optimal anesthesia dosing strategies, and to understand the mechanisms behind high neuraxial anesthesia failures for PPTL.

    View details for DOI 10.1016/j.ijoa.2023.103974

    View details for PubMedID 38508961

  • Adrenaline or noradrenaline for spinal hypotension during caesarean section - beware; the cure may be worse than the disease SOUTHERN AFRICAN JOURNAL OF ANAESTHESIA AND ANALGESIA Dyer, R. A., Carvalho, B., Blockman, M., Pfister, C. 2024; 30 (4): 100-102
  • Association of antenatal anxiety, short sleep duration, and blood pressure parameters: a pilot study Miller, H. E., Simpson, S. L., Hurtado, J., Shu, C., Chueh, J., Barwick, F., Leonard, S. A., Carvalho, B., Sultan, P., Aghaeepour, N., Druzin, M. L., Panelli, D. M. MOSBY-ELSEVIER. 2024: S287
  • Insomnia in pregnancy: are hospitalized inpatients sleeping less than outpatients? Panelli, D. M., Miller, H. E., Simpson, S. L., Hurtado, J., Shu, C., Boncompagni, A. C., Chueh, J., Barwick, F., Carvalho, B., Sultan, P., Aghaeepour, N., Druzin, M. L. MOSBY-ELSEVIER. 2024: S378
  • Physical activity among pregnant inpatients and outpatients and associations with anxiety Panelli, D. M., Miller, H. E., Simpson, S. L., Hurtado, J., Shu, C., Boncompagni, A. C., Chueh, J., Carvalho, B., Sultan, P., Aghaeepour, N., Druzin, M. L. MOSBY-ELSEVIER. 2024: S578
  • Feasibility of Focused Cardiac Ultrasound Performed by Trainees During Cesarean Delivery. Anesthesia and analgesia Ortner, C. M., Sheikh, M., Athar, M. W., Padilla, C., Guo, N., Carvalho, B. 2023

    Abstract

    Anesthesiology experts advocate for formal education in maternal critical care, including the use of focused cardiac ultrasound (FCU) in high-acuity obstetric units. While benefits and feasibility of FCU performed by experts have been well documented, little evidence exists on the feasibility of FCU acquired by examiners with limited experience. The primary aim of this study was to assess how often echocardiographic images of sufficient quality to guide clinical decision-making were attained by trainees with limited experience performing FCU in term parturients undergoing cesarean delivery (CD).In this prospective cohort study, healthy term parturients (American Society of Anesthesiologists [ASA] ≤ 3, ≥37 weeks of gestation) with singleton pregnancy, body mass index (BMI) <40 kg/m2, and no history of congenital and acquired cardiac disease undergoing scheduled, elective CD were recruited by a trainee. After undergoing standardized training, including an 8-hour online E-learning module, a 1-day hands-on FCU course, and 20 to 30 supervised scans until the trainee was assessed competent in image acquisition, 8 trainees with limited FCU experience performed apical 4-chamber (A4CH), parasternal long-axis (PLAX), and short-axis (PSAX) view preoperatively after spinal anesthesia (SPA) and intraoperatively after neonatal delivery (ND). Obtained FCU images were graded 1 to 5 by 2 blinded instructors (1 = no image to 5 = perfect image obtainable; ≥3 defined as image quality sufficient for clinical decision-making).Following the screening of 95 women, 8 trainees with limited FCU experience each performed a median of 5 [3-8] FCUs in a total of 64 women. Images of sufficient quality were obtainable in 61 (95.3 %) and 57 (89.1 %) of women after SPA and ND, respectively. FCU images of perfect image quality were obtainable in 9 (14.1 %) and 7 (10.9 %) women preoperatively after SPA and intraoperatively after ND, respectively. A PLAX, PSAX, and A4CH view with grade ≥3 was obtained in 53 (82.8 %), 58 (90.6 %) and 40 (62.5 %) of women preoperatively after SPA and in 50 (78.1 %), 49 (76.6 %), and 29 (45.3 %) of women intraoperatively after ND. Left ventricular function could be assessed in 39 of 40 women (97.5 %) preoperatively after SPA and 39 of 40 (97.5%) intraoperatively after ND. Right ventricular function could be assessed in 31 of 40 (77.5 %) after SPA and in 23 of 40 (59%) after ND. We observed a difference in image grading between different trainees in the AP4CH-view (P = .0001). No difference in image grading was found between preoperative and intraoperative FCUs.FCU is feasible in the parturient undergoing CD and images of sufficient quality for clinical decision-making were obtained by trainees with limited experience in almost all parturients. Image acquisition and quality in the A4CH view may be impacted by the individual trainee performing the FCU.

    View details for DOI 10.1213/ANE.0000000000006747

    View details for PubMedID 38127663

  • Prevalence and predictors for postpartum sleep disorders: a nationwide analysis. The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians Sultan, P., Guo, N., Kawai, M., Barwick, F. H., Carvalho, B., Mackey, S., Kallen, M. A., Gould, C. E., Butwick, A. J. 2023; 36 (1): 2170749

    Abstract

    To describe the prevalence and predictors of postpartum sleep disorders.A retrospective cohort study.Postpartum.Commercially insured women delivering in California (USA) between 2011 and 2014.Using the Optum Clinformatics Datamart Database.Prevalence of a postpartum sleep disorder diagnosis with and without a depression diagnosis up to 12 months following hospital discharge for inpatient delivery. We also identified predictors of a postpartum sleep disorder diagnosis using multivariable logistic regression.We identified 3535 (1.9%) women with a postpartum sleep disorder diagnosis. The prevalence of sleep disorder diagnoses was insomnia (1.3%), sleep apnea (0.25%), and other sleep disorder (0.25%). The odds of a postpartum sleep disorder were highest among women with a history of drug abuse (adjusted odds ratio (aOR): 2.70, 95% confidence interval (CI): 1.79-4.09); a stillbirth delivery (aOR: 2.15, 95% CI: 1.53-3.01); and chronic hypertension (aOR: 1.82; 95% CI: 1.57-2.11). A comorbid diagnosis of a postpartum sleep disorder and depression occurred in 1182 women (0.6%). These women accounted for 33.4% of all women with a postpartum sleep disorder. The strongest predictors of a comorbid diagnosis were a history of drug abuse (aOR: 4.13; 95% CI: 2.37-7.21) and a stillbirth delivery (aOR: 2.93; 95% CI: 1.74-4.92).Postpartum sleep disorders are underdiagnosed conditions, with only 2% of postpartum women in this cohort receiving a sleep diagnosis using International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes. Insomnia was the most common disorder and one-third of women diagnosed with a postpartum sleep disorder had a co-morbid diagnosis of depression. Future studies are needed to improve the screening and diagnostic accuracy of postpartum sleep disorders.

    View details for DOI 10.1080/14767058.2023.2170749

    View details for PubMedID 36710393

  • Standardizing nomenclature in regional anesthesia: an ASRA-ESRA Delphi consensus study of upper and lower limb nerve blocks. Regional anesthesia and pain medicine El-Boghdadly, K., Albrecht, E., Wolmarans, M., Mariano, E. R., Kopp, S., Perlas, A., Thottungal, A., Gadsden, J., Tulgar, S., Adhikary, S., Aguirre, J., Agur, A. M., Altıparmak, B., Barrington, M. J., Bedforth, N., Blanco, R., Bloc, S., Boretsky, K., Bowness, J., Breebaart, M., Burckett-St Laurent, D., Carvalho, B., Chelly, J. E., Chin, K. J., Chuan, A., Coppens, S., Costache, I., Dam, M., Desmet, M., Dhir, S., Egeler, C., Elsharkawy, H., Bendtsen, T. F., Fox, B., Franco, C. D., Gautier, P. E., Grant, S. A., Grape, S., Guheen, C., Harbell, M. W., Hebbard, P., Hernandez, N., Hogg, R. M., Holtz, M., Ihnatsenka, B., Ilfeld, B. M., Ip, V. H., Johnson, R. L., Kalagara, H., Kessler, P., Kwofie, M. K., Le-Wendling, L., Lirk, P., Lobo, C., Ludwin, D., Macfarlane, A. J., Makris, A., McCartney, C., McDonnell, J., McLeod, G. A., Memtsoudis, S. G., Merjavy, P., Moran, E. M., Nader, A., Neal, J. M., Niazi, A. U., Njathi-Ori, C., O'Donnell, B. D., Oldman, M., Orebaugh, S. L., Parras, T., Pawa, A., Peng, P., Porter, S., Pulos, B. P., Sala-Blanch, X., Saporito, A., Sauter, A. R., Schwenk, E. S., Sebastian, M. P., Sidhu, N., Sinha, S. K., Soffin, E. M., Stimpson, J., Tang, R., Tsui, B. C., Turbitt, L., Uppal, V., van Geffen, G. J., Vermeylen, K., Vlassakov, K., Volk, T., Xu, J. L., Elkassabany, N. M. 2023

    Abstract

    Inconsistent nomenclature and anatomical descriptions of regional anesthetic techniques hinder scientific communication and engender confusion; this in turn has implications for research, education and clinical implementation of regional anesthesia. Having produced standardized nomenclature for abdominal wall, paraspinal and chest wall regional anesthetic techniques, we aimed to similarly do so for upper and lower limb peripheral nerve blocks.We performed a three-round Delphi international consensus study to generate standardized names and anatomical descriptions of upper and lower limb regional anesthetic techniques. A long list of names and anatomical description of blocks of upper and lower extremities was produced by the members of the steering committee. Subsequently, two rounds of anonymized voting and commenting were followed by a third virtual round table to secure consensus for items that remained outstanding after the first and second rounds. As with previous methodology, strong consensus was defined as ≥75% agreement and weak consensus as 50%-74% agreement.A total of 94, 91 and 65 collaborators participated in the first, second and third rounds, respectively. We achieved strong consensus for 38 names and 33 anatomical descriptions, and weak consensus for five anatomical descriptions. We agreed on a template for naming peripheral nerve blocks based on the name of the nerve and the anatomical location of the blockade and identified several areas for future research.We achieved consensus on nomenclature and anatomical descriptions of regional anesthetic techniques for upper and lower limb nerve blocks, and recommend using this framework in clinical and academic practice. This should improve research, teaching and learning of regional anesthesia to eventually improve patient care.

    View details for DOI 10.1136/rapm-2023-104884

    View details for PubMedID 38050174

  • Intravenous Calcium to Decrease Blood Loss During Intrapartum Cesarean Delivery: A Randomized Controlled Trial. Obstetrics and gynecology Ansari, J. R., Yarmosh, A., Michel, G., Lyell, D., Hedlin, H., Cornfield, D. N., Carvalho, B., Bateman, B. T. 2023

    Abstract

    OBJECTIVE: To evaluate whether prophylactic administration of 1 g of intravenous calcium chloride after cord clamping reduces blood loss from uterine atony during intrapartum cesarean delivery.METHODS: This single-center, block-randomized, placebo-controlled, double-blind superiority trial compared the effects of 1 g intravenous calcium chloride with those of saline placebo control on blood loss at cesarean delivery. Parturients at 34 or more weeks of gestation requiring intrapartum cesarean delivery after oxytocin exposure in labor were enrolled. Calcium or saline placebo was infused over 10 minutes beginning 1minute after umbilical cord clamping in addition to standard care with oxytocin. The primary outcome was quantitative blood loss, analyzed by inverse Gaussian regression. Planned subgroup analysis excluded nonatonic bleeding, such as hysterotomy extension, arterial bleeding, and occult placenta accreta. We planned to enroll 120 patients to show a 200-mL reduction in quantitative blood loss in planned subgroup analysis, assuming up to 40% incidence of nonatonic bleeding (80% power, alpha<0.05).RESULTS: From April 2022 through March 2023, 828 laboring parturients provided consent and 120 participants were enrolled. Median blood loss was 840 mL in patients allocated to calcium chloride (n=60) and 1,051 mL in patients allocated to placebo (n=60), which was not statistically different (mean reduction 211 mL, 95% CI -33 to 410). In the planned subgroup analysis (n=39 calcium and n=40 placebo), excluding cases of surgeon-documented nonatonic bleeding, calcium reduced quantitative blood loss by 356 mL (95% CI 159-515). Rates of reported side effects were similar between the two groups (38% calcium vs 42% placebo).CONCLUSION: Prophylactic intravenous calcium chloride administered during intrapartum cesarean delivery after umbilical cord clamping did not significantly reduce blood loss in the primary analysis. However, in the planned subgroup analysis, calcium infusion significantly reduced blood loss by approximately 350 mL. These data suggest that this inexpensive and shelf-stable medication warrants future study as a novel treatment strategy to decrease postpartum hemorrhage, the leading global cause of maternal morbidity and mortality.CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT05027048.

    View details for DOI 10.1097/AOG.0000000000005441

    View details for PubMedID 37917943

  • Obstetric operating room staffing and operating efficiency using queueing theory. BMC health services research Lim, G., Lim, A. J., Quinn, B., Carvalho, B., Zakowski, M., Lynde, G. C. 2023; 23 (1): 1147

    Abstract

    Strategies to achieve efficiency in non-operating room locations have been described, but emergencies and competing priorities in a birth unit can make setting optimal staffing and operation benchmarks challenging. This study used Queuing Theory Analysis (QTA) to identify optimal birth center operating room (OR) and staffing resources using real-world data.Data from a Level 4 Maternity Center (9,626 births/year, cesarean delivery (CD) rate 32%) were abstracted for all labor and delivery operating room activity from July 2019-June 2020. QTA has two variables: Mean Arrival Rate, λ and Mean Service Rate µ. QTA formulas computed probabilities: P0 = 1-(λ/ µ) and Pn = P0 (λ/µ)n where n = number of patients. P0…n is the probability there are zero patients in the queue at a given time. Multiphase multichannel analysis was used to gain insights on optimal staff and space utilization assuming a priori safety parameters (i.e., 30 min decision to incision in unscheduled CD; ≤ 5 min for emergent CD; no greater than 8 h for nil per os time). To achieve these safety targets, a < 0.5% probability that a patient would need to wait was assumed.There were 4,017 total activities in the operating room and 3,092 CD in the study period. Arrival rate λ was 0.45 (patients per hour) at peak hours 07:00-19:00 while λ was 0.34 over all 24 h. The service rate per OR team (µ) was 0.87 (patients per hour) regardless of peak or overall hours. The number of server teams (s) dedicated to OR activity was varied between two and five. Over 24 h, the probability of no patients in the system was P0 = 0.61, while the probability of 1 patient in the system was P1 = 0.23, and the probability of 2 or more patients in the system was P≥2 = 0.05 (P3 = 0.006). However, between peak hours 07:00-19:00, λ was 0.45, µ was 0.87, s was 3, P0 was 0.48; P1 was 0.25; and P≥2 was 0.07 (P3 = 0.01, P4 = 0.002, P5 = 0.0003).QTA is a useful tool to inform birth center OR efficiency while upholding assumed safety standards and factoring peaks and troughs of daily activity. Our findings suggest QTA is feasible to guide staffing for maternity centers of all volumes through varying model parameters. QTA can inform individual hospital-level decisions in setting staffing and space requirements to achieve safe and efficient maternity perioperative care.

    View details for DOI 10.1186/s12913-023-10143-0

    View details for PubMedID 37875897

    View details for PubMedCentralID 4524929

  • Effect of an electronic medical record nudge to improve quality improvement program tracking of neuraxial catheter replacements in obstetric patients. BMJ open quality Fedoruk, K., Xie, J., Wang, E., Fowler, C., Riley, E., Carvalho, B. 2023; 12 (4)

    Abstract

    Monitoring complications associated with medical procedures requires reliable and accurate record keeping. Nudge reminders executed by way of electronic medical record (EMR) alerts influence clinician behaviour. We hypothesised that the introduction of an EMR nudge would improve documentation of replaced neuraxial blocks by obstetric anaesthesiologists at our institution.We developed an EMR nudge that would alert the physician to a replaced neuraxial block if two or more neuraxial procedure notes in a single patient encounter were detected. The nudge encouraged physicians to document neuraxial block replacements in our institution's quality improvement database. We assessed the rate of physician adherence to replaced neuraxial block charting prior to the introduction of the nudge (January 2019-September 2019) and after the implementation (October 2019-December 2020).494 encounters during the chart review period, January 2019-December 2020, required a neuraxial block replacement, representing an actual neuraxial replacement rate of 6.3% prior to the introduction of the nudge in October 2019. This rate was largely unchanged (6.2%) after the introduction of the nudge (0.1% difference, 95% CI: -0.0119 to 0.0099). Prior to the introduction of the nudge, the proportion of correctly charted failed/replaced blocks in our quality improvement database was 80.0%, and after nudge introduction, the rate was 96.2% (p value <0.00001, OR=6.32, 95% CI: 3.15 to 12.66). A p-chart of the monthly adherence rate demonstrated sustained improvement over time.EMR nudge technology significantly improved adherence with quality metric monitoring of neuraxial catheter replacement in obstetric patients. The results imply that data collection for quality metric databases of neuraxial block failures and replacements that rely on clinician memory without a nudge are likely under-reporting neuraxial block failures and replacements. This study supports widespread implementation of nudges in EMRs to improve quality metric reporting.

    View details for DOI 10.1136/bmjoq-2022-002240

    View details for PubMedID 37903567

  • Association of inpatient postpartum quality of recovery with postpartum depression: A prospective observational study. Journal of clinical anesthesia Ben Hayoun, D. H., Sultan, P., Rozeznic, J., Guo, N., Carvalho, B., Orbach-Zinger, S., Weiniger, C. F. 2023; 91: 111263

    Abstract

    To explore the relationship between Obstetric Quality of Recovery survey (ObsQoR-10-Heb) and Edinburgh postnatal depression scale (EPDS) measured 6 weeks after delivery, adjusted for potential confounding factors.Prospective, longitudinal cohort study.Large postpartum department, 13,000 annual deliveries, quaternary medical center in Israel.Women ≥18 years old, gestational age ≥ 37 weeks after term delivery (spontaneous vaginal, operative vaginal, planned, and unplanned cesarean delivery), with non-anomalous neonates not requiring special support after delivery or at the time of recruitment. Written informed consent was provided. Women unable to read or understand Hebrew were excluded.No interventions were done.We investigated the relationship between inpatient postpartum recovery and positive postpartum depression (PPD) screening at 6 weeks postpartum. Enrolled women completed the validated Hebrew version of ObsQoR-10 survey (ObsQoR-10-Heb; scored between 0 and 100 with 0 and 100 representing worst and best possible recovery) from 24 to 48 h after delivery, and the Edinburgh Postnatal Depression Scale (EPDS) at 6- and 12 weeks postpartum. We assessed the univariate association between ObsQoR-10-Heb; patient factors; obstetric factors; and positive PPD screening at 6 weeks postpartum. Potential confounders were adjusted in a multiple logistic regression model.Inpatient ObsQoR-10-Heb has been completed by 325 postpartum women; 270 (83.1%) and 253 (77.9%) completed the 6- and 12 weeks EPDS respectively. Lower ObsQoR-10-Heb (aOR 0.95 (95% CI 0.92, 0.98); p = 0.001); depression or anxiety before delivery (aOR 4.53 (95% CI 1.88, 10.90); p = 0.001); and hospital readmission (aOR 9.08 (95% CI 1.23, 67.14); p = 0.031) were associated with positive screening for postpartum depression at 6 weeks.Our study demonstrates that worse inpatient postpartum recovery is an independent risk factor for positive PPD screening at 6 weeks postpartum. Other risk factors found in our study were maternal hospital readmission and a previous history of anxiety or depression.

    View details for DOI 10.1016/j.jclinane.2023.111263

    View details for PubMedID 37717463

  • Outcomes and outcome measures utilised in randomised controlled trials of postoperative caesarean delivery pain: a scoping review. International journal of obstetric anesthesia Ciechanowicz, S., Kim, J., Mak, K., Blake, L., Carvalho, B., Sultan, P. 2023: 103927

    Abstract

    Inadequately treated postoperative pain following caesarean delivery can delay recovery and the ability to care for a newborn. Effectiveness studies of interventions to treat postoperative caesarean delivery pain measure different outcomes, limiting data pooling for meta-analysis. We performed a comprehensive review of existing outcomes with the aim of recommending core outcomes for future research.A scoping review to identify all outcomes reported in randomised controlled trials (RCTs) and clinical trial registries of interventions to treat or prevent postoperative caesarean delivery pain, with postoperative pain as a primary outcome measure. We searched PubMed, Web of Science, CINAHL, LILACS, Embase, CDSR and CRCT for studies from May 2016 to 2021. Outcomes were extracted and frequencies tabulated.Ninety RCTs and 11 trial registries were included. In total, 392 outcomes (375 inpatient and 17 outpatient) were identified and categorised. The most reported outcome domain was analgesia (n = 242/375, 64.5%), reported in 96% of inpatient studies, with analgesic consumption accounting for 108/375, 28.8% of analgesia outcomes. The second most common domain was pain intensity (n = 120/375, 32%), reported in 97% of inpatient studies, using the visual analogue scale (68/120, 59%) and the numerical reporting scale (37/120, 25%). Maternal and neonatal adverse effects accounted for 65/375 (17.3%) and 19/375 (5.1%) of inpatient outcomes, respectively.Outcomes reported in RCTs for postoperative caesarean delivery pain vary widely. The results of this review suggest that standardisation is needed to promote research efficiency and aid future meta-analyses to identify optimal postoperative caesarean delivery pain management.

    View details for DOI 10.1016/j.ijoa.2023.103927

    View details for PubMedID 37852907

  • Investigation of the Optimum Baseline Blood Pressure for Spinal Anesthesia to Guide Vasopressor Management for Elective Cesarean Delivery: A Case-Control Design. Cureus Kovacheva, V. P., Armero, W., Zhou, G., Bishop, D., Dyer, R., Carvalho, B. 2023; 15 (9): e45380

    Abstract

    Current guidelines recommend prophylactic vasopressor administration during spinal anesthesia for cesarean delivery to maintain intraoperative blood pressure above 90% of the baseline value. We sought to determine the optimum baseline mean arterial pressure (MAP) reading to guide the management of spinal hypotension.We performed a secondary analysis of data collected from normotensive patients presenting for elective cesarean delivery in a tertiary care institution from October 2018 to August 2020. We compared the magnitude of hypotension in patients who reported nausea versus those who did not, using a case-control design. Baseline MAPs at last office visit, morning of surgery, or operating room (pre-spinal) were determined. We calculated the duration and degree of hypotension using the area under the curve (AUC) when the MAP of the respective patient was below 90% of each baseline.The patients who experienced nausea (n=45) had longer and more profound periods of hypotension than those who did not develop nausea (n=240). A comparison of AUC using MAP baseline at the last office visit or on the morning of surgery showed a statistically significant between-group difference, P=0.02, and P=0.005, respectively, and no significant between-group difference when 90% of the MAP baseline in the operating room was used.Patients had the highest preoperative MAP in the operating room and the AUC was similar for those with and without nausea when the pre-spinal MAP baseline was used. Therefore, maintaining higher intraoperative blood pressure using individual pre-spinal MAP as baseline should reduce intraoperative maternal nausea.

    View details for DOI 10.7759/cureus.45380

    View details for PubMedID 37854732

    View details for PubMedCentralID PMC10579048

  • Postpartum recovery of nulliparous women following scheduled cesarean delivery and spontaneous vaginal delivery: a prospective observational study. AJOG global reports Mazda, Y., Ando, K., Kato, A., Noguchi, S., Sugiyama, T., Hizuka, K., Nagai, A., Ikeda, Y., Sakamaki, D., Guo, N., Carvalho, B., Sultan, P. 2023; 3 (3): 100226

    Abstract

    Inpatient postpartum recovery trajectories following cesarean delivery and spontaneous vaginal delivery are underexplored.This study primarily aimed to compare recovery following cesarean delivery and spontaneous vaginal delivery in the first postpartum week, and secondarily to evaluate psychometrically the Japanese version of the Obstetric Quality of Recovery-10 scoring tool.Following institutional review board approval, the EQ-5D-3L (EuroQoL 5-Dimension 3-Level) questionnaire and a Japanese version of the Obstetric Quality of Recovery-10 measure were used to evaluate inpatient postpartum recovery in uncomplicated nulliparous parturients delivering via scheduled cesarean delivery or spontaneous vaginal delivery.A total of 48 and 50 women who delivered via cesarean delivery and spontaneous vaginal delivery, respectively, were recruited. Women delivering via scheduled cesarean delivery experienced significantly worse quality of recovery on days 1 and 2 compared with those who had spontaneous vaginal delivery. Quality of recovery significantly improved daily, plateauing at days 4 and 3 for cesarean delivery and spontaneous vaginal delivery groups, respectively. Compared with cesarean delivery, spontaneous vaginal delivery was associated with prolonged time to analgesia requirement, decreased opioid consumption, reduced antiemetic requirement, and reduced times to liquid/solid intake, ambulation, and discharge. Obstetric Quality of Recovery-10-Japanese is a valid (correlates with the EQ-5D-3L including a global health visual analog scale, gestational age, blood loss, opioid consumption, time until first analgesic request, liquid/solid intake, ambulation, catheter removal, and discharge), reliable (Cronbach alpha=0.88; Spearman-Brown reliability estimate=0.94; and intraclass correlation coefficient=0.89), and clinically feasible (98% 24-hour response rate) measure.Inpatient postpartum recovery is significantly better in the first 2 postpartum days following spontaneous vaginal delivery compared with scheduled cesarean delivery. Inpatient recovery is largely achieved within 4 and 3 days following scheduled cesarean delivery and spontaneous vaginal delivery, respectively. Obstetric Quality of Recovery-10-Japanese is a valid, reliable, and feasible measure of inpatient postpartum recovery.

    View details for DOI 10.1016/j.xagr.2023.100226

    View details for PubMedID 37334251

    View details for PubMedCentralID PMC10276254

  • Erratum to "A randomized trial to investigate needle redirections/re-insertions using a handheld ultrasound device versus traditional palpation for spinal anesthesia in obese women undergoing cesarean delivery" [Int. J. Obstetric Anesth. 49 (2022) 103229]. International journal of obstetric anesthesia Weiniger, C. F., Carvalho, B., Ronel, I., Greenberger, C., Aptekman, B., Almog, O., Kagan, G., Shalev, S. 2023: 103903

    View details for DOI 10.1016/j.ijoa.2023.103903

    View details for PubMedID 37516605

  • Pharmacological agents for prevention of pruritus in women undergoing Caesarean delivery with neuraxial morphine: a systematic review and Bayesian network meta-analysis. British journal of anaesthesia Singh, P. M., Sultan, P., O'Carroll, J., Blake, L., Carvalho, B., Singh, N. P., Monks, D. T. 2023

    Abstract

    Neuraxial opioids provide effective analgesia for Caesarean delivery, however, pruritus can be a troubling side-effect. Effective agents to prevent pruritus are needed. Our objective was to perform an updated systematic review and network meta-analysis to provide clinicians with a comparison of relative efficacy of available interventions to reduce the incidence of pruritus, induced by either intrathecal or epidural single-shot morphine, in women undergoing Caesarean delivery.Databases systematically searched (up to January 2022) included PubMed MEDLINE, Web of Science, EBSCO CINAHL, Embase, LILACS, and two Cochrane databases. We included randomised, controlled trials involving adult female patients undergoing Caesarean delivery. We pooled trials comparing interventions used for preventing pruritus after Caesarean delivery and performed a Bayesian model network meta-analysis.The final primary network included data from comparisons of 14 distinct interventions (including placebo) used to reduce the incidence of pruritus in 6185 participants. We judged five interventions to be 'definitely superior' to placebo: propofol, opioid agonist-antagonists (neuraxial), opioid antagonists, opioid agonist-antagonists (systemic), and serotonin antagonists. For the network evaluating the incidence of severe pruritus (warranting additional therapeutic treatment of pruritus), data were available for 14 interventions (including placebo) in 4489 patients. For this outcome, we judged three interventions to be 'definitely superior' to placebo: dopamine antagonists (neuraxial) and systemic and neuraxial opioid agonist-antagonists.Our analysis found several interventions to be effective in reducing the incidence of pruritus. Although sub-hypnotic doses of propofol appear to have an antipruritic effect, replication of this finding and further investigation of optimal dosing are warranted.PROSPERO (CRD42022367058).

    View details for DOI 10.1016/j.bja.2023.05.028

    View details for PubMedID 37455197

  • A systematic review of patient-reported outcome measures used in maternal postpartum anxiety. American journal of obstetrics & gynecology MFM O'Carroll, J., Ando, K., Yun, R., Panelli, D., Nicklin, A., Kennedy, N., Carvalho, B., Blake, L., Coker, J., Kaysen, D., Sultan, P. 2023: 101076

    Abstract

    To perform a systematic review and evaluate the psychometric measurement properties of instruments in postpartum anxiety using Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines and identify the best available patient-reported outcome measure.We searched 4 databases (CINAHL, Embase, PubMed, and Web of Science in July 2022) including studies which evaluated at least one psychometric measurement property of a patient reported outcome measurement instrument. The protocol was registered with PROSPERO CRD42021260004 and followed the COSMIN guidelines for systematic reviews.Studies eligible for inclusion included those that assessed a patient-reported outcome measure examining postpartum anxiety. We included studies where the instruments had undergone some form of psychometric property assessment in the postpartum maternal population, consisted of at least 2 questions, and were not subscales.This systematic review used COSMIN and Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to identify the best patient reported outcome measurement instrument for postpartum anxiety. A risk of bias assessment was performed, and a modified GRADE approach used to assess the level of evidence with recommendations being made for the overall quality of each instrument.A total of 28 studies evaluating 13 instruments in 10,570 patients were included. Content validity was sufficient in 9, with 5 instruments receiving a class A recommendation (recommended for use). Postpartum Specific Anxiety Scale, Postpartum Specific Anxiety Scale Research Short Form, Postpartum Specific Anxiety Scale Research Short Form Covid, Postpartum Specific Anxiety Scale- Persian and State-Trait Anxiety Inventory demonstrated adequate content validity and sufficient internal consistency. Nine instruments received a recommendation of class B (further research required). No instrument received a class C recommendation (not recommended for use).Five instruments received a class A recommendation, all with limitations such as not being specific to the postpartum population, not assessing all domains, lacking generalizability or evaluation of cross-cultural validity. There is currently no freely available instrument assessing all domains of postpartum anxiety. Future studies are needed to determine the optimum current instrument or development and validation of a more specific measure for maternal postpartum anxiety.

    View details for DOI 10.1016/j.ajogmf.2023.101076

    View details for PubMedID 37402438

  • Quality of recovery following childbirth: a prospective, multicentre cohort study. Anaesthesia O'Carroll, J. E., Zucco, L., Warwick, E., Arbane, G., Moonesinghe, S. R., El-Boghdadly, K., Guo, N., Carvalho, B., Sultan, P. 2023

    Abstract

    To better understand outcomes in postpartum patients who receive peripartum anaesthetic interventions, we aimed to assess quality of recovery metrics following childbirth in a UK-based multicentre cohort study. This study was performed during a 2-week period in October 2021 to assess in- and outpatient post-delivery recovery at 1 and 30 days postpartum. The following outcomes were reported: obstetric quality of recovery 10-item measure (ObsQoR-10); EuroQoL (EQ-5D-5L) survey; global health visual analogue scale; postpartum pain scores at rest and movement; length of hospital stay; readmission rates; and self-reported complications. In total, 1638 patients were recruited and responses analysed from 1631 (99.6%) and 1282 patients (80%) at one and 30 days postpartum, respectively. Median (IQR [range]) length of stay postpartum was 39.3 (28.5-61.0 [17.7-513.4]), 40.3 (28.5-59.1 [17.8-220.9]), and 35.9 (27.1-54.1 [17.9-188.4]) h following caesarean, instrumental and vaginal deliveries, respectively. Median (IQR [range]) ObsQoR-10 score was 75 ([62-86] 4-100) on day 1, with the lowest ObsQoR-10 scores (worst recovery) reported by patients undergoing caesarean delivery. Of the 1282 patients, complications within the first 30 days postpartum were reported by 252 (19.7%) of all patients. Readmission to hospital within 30 days of discharge occurred in 69 patients (5.4%), with 49 (3%) for maternal reasons. These data can be used to inform patients regarding expected recovery trajectories; facilitate optimal discharge planning; and identify populations that may benefit most from targeted interventions to improve postpartum recovery experience.

    View details for DOI 10.1111/anae.16039

    View details for PubMedID 37226593

  • Automated Alert System of Second-Line Uterotonic Drug Administration. A&A practice Abir, G., Riley, E. T., Oakeson, A. M., Judy, A., Wang, E., Carvalho, B. 2023; 17 (5): e01687

    Abstract

    Multidisciplinary team management of postpartum hemorrhage (PPH) is needed to optimize care and improve outcomes. Lucile Packard Children's Hospital, Stanford, is a tertiary referral center with 4600 deliveries/y (>70% high-risk deliveries), and there have been times when the obstetric anesthesia team was alerted late or not at all for PPHs. Introduction of an automated alert process to the obstetric anesthesia team when a second-line uterotonic drug was administered has ensured prompt evaluation. Utilization of this automated drug alert system has improved communication and reduced failure to inform the obstetric anesthesiology team of PPH after vaginal and cesarean deliveries.

    View details for DOI 10.1213/XAA.0000000000001687

    View details for PubMedID 37222414

  • Comparison of different nonsteroidal anti-inflammatory drugs for cesarean section: a systematic review and network meta-analysis. Korean journal of anesthesiology Murdoch, I., Carver, A., Sultan, P., O'Carroll, J., Blake, L., Carvalho, B., Onwochei, D. N., Desai, N. 2023

    Abstract

    Cesarean section is associated with moderate to severe pain and nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly employed. The optimal NSAID, however, has not been elucidated. In this network meta-analysis and systematic review, we compared the influence of control and individual NSAIDs on indices of analgesia, side effects and quality of recovery.CDSR, CINAHL, CRCT, Embase, LILACS, PubMed and Web of Science were searched for randomized controlled trials which compared a specific NSAID to either control or another NSAID in the context of elective or emergency cesarean section under general or neuraxial anesthesia. Network plots and league tables were constructed, and the quality of evidence was evaluated with GRADE analysis.In all, we included 47 trials. Cumulative intravenous morphine equivalent consumption at 24 h, the primary outcome, was examined in 1228 patients and 18 trials, and control was found to be inferior to diclofenac, indomethacin, ketorolac and tenoxicam (very low quality of evidence owing to serious limitations, imprecision and publication bias). Indomethacin was superior to celecoxib for the pain score at rest at 8-12 h and celecoxib + parecoxib, diclofenac and ketorolac for the pain score on movement at 48 h. In regard to the need for and time to rescue analgesia, cyclooxygenase two inhibitors such as celecoxib were inferior to other NSAIDs.Our review suggests the presence of minimal differences among the NSAIDs studied. Nonselective NSAIDs may be more effective than selective NSAIDs, and some NSAIDs such as indomethacin might be preferable to other NSAIDs.

    View details for DOI 10.4097/kja.23014

    View details for PubMedID 37066603

  • Data-driven longitudinal characterization of neonatal health and morbidity. Science translational medicine De Francesco, D., Reiss, J. D., Roger, J., Tang, A. S., Chang, A. L., Becker, M., Phongpreecha, T., Espinosa, C., Morin, S., Berson, E., Thuraiappah, M., Le, B. L., Ravindra, N. G., Payrovnaziri, S. N., Mataraso, S., Kim, Y., Xue, L., Rosenstein, M. G., Oskotsky, T., Marić, I., Gaudilliere, B., Carvalho, B., Bateman, B. T., Angst, M. S., Prince, L. S., Blumenfeld, Y. J., Benitz, W. E., Fuerch, J. H., Shaw, G. M., Sylvester, K. G., Stevenson, D. K., Sirota, M., Aghaeepour, N. 2023; 15 (683): eadc9854

    Abstract

    Although prematurity is the single largest cause of death in children under 5 years of age, the current definition of prematurity, based on gestational age, lacks the precision needed for guiding care decisions. Here, we propose a longitudinal risk assessment for adverse neonatal outcomes in newborns based on a deep learning model that uses electronic health records (EHRs) to predict a wide range of outcomes over a period starting shortly before conception and ending months after birth. By linking the EHRs of the Lucile Packard Children's Hospital and the Stanford Healthcare Adult Hospital, we developed a cohort of 22,104 mother-newborn dyads delivered between 2014 and 2018. Maternal and newborn EHRs were extracted and used to train a multi-input multitask deep learning model, featuring a long short-term memory neural network, to predict 24 different neonatal outcomes. An additional cohort of 10,250 mother-newborn dyads delivered at the same Stanford Hospitals from 2019 to September 2020 was used to validate the model. Areas under the receiver operating characteristic curve at delivery exceeded 0.9 for 10 of the 24 neonatal outcomes considered and were between 0.8 and 0.9 for 7 additional outcomes. Moreover, comprehensive association analysis identified multiple known associations between various maternal and neonatal features and specific neonatal outcomes. This study used linked EHRs from more than 30,000 mother-newborn dyads and would serve as a resource for the investigation and prediction of neonatal outcomes. An interactive website is available for independent investigators to leverage this unique dataset: https://maternal-child-health-associations.shinyapps.io/shiny_app/.

    View details for DOI 10.1126/scitranslmed.adc9854

    View details for PubMedID 36791208

  • Assessment of fatigue in postpartum women using patient-reported outcome measures: a systematic review utilising Consensus Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines FATIGUE-BIOMEDICINE HEALTH AND BEHAVIOR Ciechanowicz, S., Pandal, P., Carvalho, B., Blake, L., Van Damme, S., Taylor, J., Sultan, P. 2022
  • A Systematic Scoping Review of Peridelivery Pain Management for Pregnant People With Opioid Use Disorder: From the Society for Obstetric Anesthesia and Perinatology and Society for Maternal Fetal Medicine. Anesthesia and analgesia Lim, G., Soens, M., Wanaselja, A., Chyan, A., Carvalho, B., Landau, R., George, R. B., Klem, M. L., Osmundson, S. S., Krans, E. E., Terplan, M., Bateman, B. T. 2022

    Abstract

    The prevalence of pregnant people with opioid use disorder (OUD), including those receiving medications for opioid use disorder (MOUD), is increasing. Challenges associated with pain management in people with OUD include tolerance, opioid-induced hyperalgesia, and risk for return to use. Yet, there are few evidence-based recommendations for pain management in the setting of pregnancy and the postpartum period, and many peripartum pain management studies exclude people with OUD. This scoping review summarized the available literature on peridelivery pain management in people with OUD, methodologies used, and identified specific areas of knowledge gaps. PubMed and Embase were comprehensively searched for publications in all languages on peripartum pain management among people with OUD, both treated with MOUD and untreated. Potential articles were screened by title, abstract, and full text. Data abstracted were descriptively analyzed to map available evidence and identify areas of limited or no evidence. A total of 994 publications were imported for screening on title, abstracts, and full text, yielding 84 publications identified for full review: 32 (38.1%) review articles, 14 (16.7%) retrospective studies, and 8 (9.5%) case reports. There were 5 randomized controlled trials. Most studies (64%) were published in perinatology (32; 38.1%) journals or anesthesiology (22; 26.2%) journals. Specific areas lacking trial or systematic review evidence include: (1) methods to optimize psychological and psychosocial comorbidities relevant to acute pain management around delivery; (2) alternative nonopioid and nonpharmacologic analgesia methods; (3) whether or not to use opioids for severe breakthrough pain and how best to prescribe and monitor its use after discharge; (4) monitoring for respiratory depression and sedation with coadministration of other analgesics; (5) optimal neuraxial analgesia dosing and adjuncts; and (6) benefits of abdominal wall blocks after cesarean delivery. No publications discussed naloxone coprescribing in the labor and delivery setting. We observed an increasing number of publications on peripartum pain management in pregnant people with OUD. However, existing published works are low on the pyramid of evidence (reviews, opinions, and retrospective studies), with a paucity of original research articles (<6%). Opinions are conflicting on the utility and disutility of various analgesic interventions. Studies generating high-quality evidence on this topic are needed to inform care for pregnant people with OUD. Specific research areas are identified, including utility and disutility of short-term opioid use for postpartum pain management, role of continuous wound infiltration and truncal nerve blocks, nonpharmacologic analgesia options, and the best methods to support psychosocial aspects of pain management.

    View details for DOI 10.1213/ANE.0000000000006167

    View details for PubMedID 36135926

  • Obstetric services in the UK during the COVID-19 pandemic: A national survey. Anaesthesia, critical care & pain medicine O'Carroll, J. E., Zucco, L., Warwick, E., Arbane, G., Moonesinghe, R., El-Boghdadly, K., Guo, N., Carvalho, B., Sultan, P. 2022: 101137

    Abstract

    The management of obstetric patients with coronavirus disease 2019 (COVID-19) due to human-to-human transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requires unique considerations. Many aspects of labour and delivery practice required adaptation in response to the global pandemic and were supported by guidelines from the Royal College of Obstetrics and Gynaecologists. The adoption and adherence to these guidelines is unknown.Participating centres in "Quality of Recovery in Obstetric Anaesthesia study - a multicentre study" (ObsQoR) completed an electronic survey based on the provision of services and care related to COVID-19 in October 2021. The survey was designed against the Royal College of Obstetricians and Gynaecologists COVID-19 guidelines.One hundred and five of the 107 participating centres completed the survey (98% response rate representing 54% of all UK obstetric units). The median [IQR] annual number of deliveries among the included sites was 4389 [3000-5325]. Ninety-nine of the 103 (94.3%) sites had guidelines for the management of peripartum women with COVID-19. Sixty-one of 105 (58.1%) had specific guidance for venous thromboembolism (VTE) prophylaxis. Thirty-seven of 104 (35.6%) centres restricted parturient birthing plans if a positive diagnosis of COVID-19 was made. A COVID-19 vaccination referral pathway encouraging full vaccination for all pregnant women was present in 63/103 centres (61.2%).We found variability in care delivered and adherence to guidelines related to COVID-19. The clinical implications for this related to quality of peripartum care is unclear, however there remains scope to improve pathways for immunisation, birth plans and VTE prophylaxis.

    View details for DOI 10.1016/j.accpm.2022.101137

    View details for PubMedID 35914704

  • Incidence, prevalence, and timing of postpartum complications and mortality in Canada and the United States: a systematic review and meta-analysis protocol. JBI evidence synthesis Ke, J. X., Vidler, M., Dol, J., Carvalho, B., Blake, L. E., George, R. B., Bone, J., Seligman, K., Coombs, M., Chau, A. A., Saville, L., Gibbs, R. S., Sultan, P. 2022

    Abstract

    The goal of this systematic review is to assess the incidence, prevalence, and timing of common postpartum (up to one year after delivery) medical, surgical/procedural, and psychosocial complications and mortality.Childbirth is the most common cause for hospitalization, and cesarean delivery is the most commonly performed inpatient surgery. After delivery, mothers are at risk of short- and long-term complications that can impact their well-being. The results of this review will inform evidence-based recommendations for patient education, monitoring, and follow-up.We will include studies performed in Canada and/or the United States that report the incidence or prevalence of medical, procedural/surgical, and psychosocial complications within one year postpartum. Observational studies (analytical cross-sectional studies, retrospective and prospective cohorts), randomized or non-randomized controlled trials with a control or standard of care group, systematic reviews, and meta-analyses will be included. Studies with <100 patients, age <18 years, no reporting of duration, and focus on patients with a specific condition rather than a general postpartum population will be excluded.The search strategy was co-developed with a medical librarian and included full-text English-language articles published within the past 10 years (2011-2021) in PubMed, CINHAL, Web of Science, and Cochrane Database of Systematic Reviews. Screening, critical appraisal, and data extraction will be performed by two independent reviewers using Covidence, standardized JBI tools, and a standardized form, respectively. For each complication, the incidence or prevalence, timing of the frequency measurement, and duration of follow-up from individual studies will be determined. Meta-analysis will be performed if feasible.PROSPERO CRD42022303047.

    View details for DOI 10.11124/JBIES-21-00437

    View details for PubMedID 35975310

  • Obstetric Anesthesia Procedure-Based Workload and Facility Utilization of Society of Obstetric Anesthesia and Perinatology Centers of Excellence Designated Institutions. Anesthesia and analgesia Im, M., Riley, E. T., Hoang, D., Lim, G., Zakowski, M., Carvalho, B. 2022

    Abstract

    BACKGROUND: Optimal workload and staffing for obstetric anesthesia services have yet to be determined. We surveyed Society of Obstetric Anesthesia and Perinatology (SOAP) Centers of Excellence (COE) for Obstetric Anesthesia Care institutions to evaluate procedure-based obstetric anesthesia workload and facility use.METHODS: After institutional review board (IRB) exemption, an online survey instrument (REDCap) was sent by email (1 initial and 2 reminders) to all SOAP COEs. Survey data included the number of deliveries, cesarean delivery rate, neuraxial labor analgesia rate, the number of labor and operating rooms, and the number of in-house and backup obstetric anesthesia providers. Obstetric anesthesia activity was estimated using a time-based workload ratio per provider (Stanford Work Index, 1.0 = clinically working every minute of every hour on duty) during weekday, weeknight, and weekend shifts. We compared workload between academic and nonacademic centers and correlated operating and labor rooms with cesarean and vaginal delivery volume.RESULTS: Fifty-one of 53 surveys were returned (96% response rate). Data from 33 academic and 14 nonacademic US institutions were analyzed. For academic centers, median Stanford Work Index for all staff (included trainees and Certified Registered Nurse Anesthetists) was 0.20 (weekday) and 0.19 (weeknight and weekends); nonacademic centers were 0.33 (weekday, P < .001 versus academic), 0.23 (weeknight, P = .009 versus academic), and 0.23 (weekends, P = .03 versus academic practices). Attending-only Stanford Work Indices were similar between academic and nonacademic centers. Total number of rooms on the obstetric suite (operating, labor, or triage room) was strongly correlated with delivery volume (R2 = 0.55).CONCLUSIONS: The results outline staffing procedure-based workload ratios and facility utilization at SOAP COEs in the United States. These data can be used by other institutions that provide obstetric anesthesia services to guide their obstetric anesthesia staffing. The importance of considering the workload associated with different shifts and between academic and nonacademic centers is also highlighted. The results show that approximately one-third of an obstetric anesthesiologist's workload is spent on performing procedures. We did not, however, measure the other tasks anesthesiologists practice as peripartum physicians (eg, managing critically ill parturients, doing pre- and postprocedural evaluations, or performing emergent and unexpected procedures), and future studies are required to determine the time required to perform these tasks. Studies to determine the optimal staffing models to handle workload fluctuations and improve outcomes are also required.

    View details for DOI 10.1213/ANE.0000000000006112

    View details for PubMedID 35759390

  • Assessment of Patient-Reported Outcome Measures for Maternal Postpartum Depression Using the Consensus-Based Standards for the Selection of Health Measurement Instruments Guideline: A Systematic Review. JAMA network open Sultan, P., Ando, K., Elkhateb, R., George, R. B., Lim, G., Carvalho, B., Chitneni, A., Kawai, R., Tulipan, T., Blake, L., Coker, J., O'Carroll, J. 2022; 5 (6): e2214885

    Abstract

    Importance: Maternal depression is frequently reported in the postpartum period, with an estimated prevalence of approximately 15% during the first postpartum year. Despite the high prevalence of postpartum depression, there is no consensus regarding which patient-reported outcome measure (PROM) should be used to screen for this complex, multidimensional construct.Objective: To evaluate psychometric measurement properties of existing PROMs of maternal postpartum depression using the Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) guideline and identify the best available patient-reported screening measure.Evidence Review: This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline. PubMed, CINAHL, Embase, and Web of Science were searched on July 1, 2019, for validated PROMs of postpartum depression, and an additional search including a hand search of references from eligible studies was conducted in June 2021. Included studies evaluated 1 or more psychometric measurement properties of the identified PROMs. A risk-of-bias assessment was performed to evaluate methods of each included study. Psychometric measurement properties of each PROM were rated according to COSMIN criteria. A modified Grading of Recommendations Assessment, Development, and Evaluation approach was used to assess the level of evidence supporting each rating, and a recommendation class (A, recommended for use; B, further research required; or C, not recommended) was given based on the overall quality of each included PROM.Findings: Among 10 264 postpartum recovery studies, 27 PROMs were identified. Ten PROMs (37.0%) met the inclusion criteria and were used in 43 studies (0.4%) involving 22 095 postpartum women. At least 1 psychometric measurement property was assessed for each of the 10 validated PROMs identified. Content validity was sufficient in all PROMs. The Edinburgh Postnatal Depression Scale (EPDS) demonstrated adequate content validity and a moderate level of evidence for sufficient internal consistency (with sufficient structural validity), resulting in a recommendation of class A. The other 9 PROMs evaluated received a recommendation of class B.Conclusions and Relevance: The findings of this systematic review suggest that the EPDS is the best available patient-reported screening measure of maternal postpartum depression. Future studies should focus on evaluating the cross-cultural validity, reliability, and measurement error of the EPDS to improve understanding of its psychometric properties and utility.

    View details for DOI 10.1001/jamanetworkopen.2022.14885

    View details for PubMedID 35749118

  • Virtual Compared to In-Person Obstetric Anesthesiology Trainee Education During the COVID-19 Pandemic: A Short Report. Cureus Fedoruk, K., Abir, G., Carvalho, B. 2022; 14 (6): e26423

    Abstract

    BACKGROUND: The COVID-19 pandemic brought many changes to medical training, including in-person education platforms being disbanded and replaced with virtual education. At our institution, dedicated obstetric anesthesiology teaching for residents and fellows occurs daily and is highly valued and rated. In March 2020 due to the COVID-19 pandemic, we changed the teaching platform from in-person to virtual teaching (via video communication). We subsequently surveyed residents, fellows, and attendings to determine the impact of virtual compared with in-person teaching.METHODS: To assess the impact of this change, an electronic survey was sent to 10 anesthesiology residents on their 2nd obstetric anesthesiology rotation, and 10 residents on their 1st rotation, respectively. The electronic survey was also sent to three fellows and eight obstetric anesthesiology attendings. Answers were based on a 5-point Likert scale (1 = strongly disagree, 5 = strongly agree).RESULTS: The results for 1st rotation residents were higher in all domains compared with 2nd rotation residents and fellows, where "quality" achieved statistical significance (p=0.009) between 1st and 2nd rotation residents. "Engagement" was overall the most impacted domain for trainees. Attendings did not feel that virtual teaching impacted their ability to provide adequate education, however, learner engagement was again the lowest rated domain, and teachers strongly favored resuming in-person teaching.CONCLUSIONS: Virtual teaching is an appropriate alternative when in-person teaching is not possible. Future initiatives are needed to improve engagement and better facilitate virtual teaching.

    View details for DOI 10.7759/cureus.26423

    View details for PubMedID 35915679

  • Storage of emergency airway equipment on labor and delivery units. Journal of clinical anesthesia Riley, E. T., Carvalho, B., Abir, G. 2022; 80: 110886

    View details for DOI 10.1016/j.jclinane.2022.110886

    View details for PubMedID 35623264

  • Expert Consensus Regarding Core Outcomes for Enhanced Recovery after Cesarean Delivery Studies: A Delphi study. Anesthesiology Sultan, P., George, R., Weiniger, C. F., El-Boghdadly, K., Pandal, P., Carvalho, B., CRADLE Study Investigators, Ansari, J. R., Benhamou, D., Baluku, M., Bernstein, P. S., Bollag, L. A., Bowden, S. J., Fay, E., Habib, A. S., Halder, S., Landau, R., Lim, G., Liu, V., Moreno, C., Nelson, G. S., Powell, M. F., Pujic, B., Sharawi, N., Singh, N., Smith, R., Stockert, E., Sultan, E., Tiouririne, M., Wilson, R. D., Wrench, I. J., Yun, R., Zakowski, M. 2022

    Abstract

    BACKGROUND: Heterogeneity among reported outcomes from enhanced recovery after cesarean delivery impact studies is high. This study aimed to develop a standardized enhanced recovery core outcome set for use in future enhanced recovery after cesarean delivery studies.METHODS: An international consensus study involving physicians, patients and a director of Midwifery and Nursing Services, was conducted using a three-round modified Delphi approach (2 rounds of electronic questionnaires and a 3rd round e-discussion), to produce the core outcome set. An initial list of outcomes was based on a previously published systematic review. Consensus was obtained for the final core outcome set, including definitions for key terms, and preferred units of measurement. Strong consensus was defined as ≥70% agreement and weak consensus as 50-69% agreement. Of the 64 stakeholders who were approached, 32 agreed to participate. All 32, 31 and 26 stakeholders completed Rounds 1, 2 and 3, respectively.RESULTS: The number of outcomes in the final core outcome set was reduced from 98 to 15. Strong consensus (≥70% stakeholder agreement) was achieved for 15 outcomes. The core outcome set included: length of hospital stay; compliance with enhanced recovery protocol; maternal morbidity (hospital re-admissions or unplanned consultations); provision of optimal analgesia (maternal satisfaction, compliance with analgesia, opioid consumption / requirement and incidence of nausea or vomiting); fasting times; breastfeeding success; and times to mobilization and urinary catheter removal. The Obstetric Quality of Recovery-10 item composite measure was also included in the final core outcome set. Areas identified as requiring further research included readiness for discharge and analysis of cost savings.CONCLUSIONS: Results from an international consensus to develop a core outcome set for enhanced recovery after cesarean delivery are presented. These are outcomes that could be considered when designing future enhanced recovery studies.

    View details for DOI 10.1097/ALN.0000000000004263

    View details for PubMedID 35511169

  • Enhancing recovery after cesarean delivery - A narrative review. Best practice & research. Clinical anaesthesiology O'Carroll, J., Carvalho, B., Sultan, P. 2022; 36 (1): 89-105

    Abstract

    Enhanced recovery after cesarean delivery (ERAC) is increasingly being implemented worldwide with the aim to improve patient care for women undergoing this procedure. ERAC is associated with superior maternal outcomes including decreased length of hospital stay, opioid consumption, pain scores, times to mobilization and urinary catheter removal and hospitalization costs,without increasing hospital readmission rates. A number of preoperative, intraoperative, and postoperative interventions have been incorporated into ERAC protocols. The evidence base for each intervention varies, and there is a lack of consensus as to which are the best and most appropriate interventions. The quality of evidence of studies evaluating ERAC is low, and the measurements for reporting its success are varied and disparate. Protocols rarely assess patient-reported outcome measures, patient satisfaction, or patient experience. The best measures of ERAC success are yet to be fully elucidated. Further work is required to evaluate protocols, interventions, and how best to measure the effect of ERAC.

    View details for DOI 10.1016/j.bpa.2022.01.001

    View details for PubMedID 35659963

  • Comparing Postpartum Estimated and Quantified Blood Loss Among Racial Groups: An Observational Study. Cureus Katz, D., Khadge, S., Carvalho, B. 2022; 14 (5): e25299

    Abstract

    Racial and ethnic disparities in peripartum blood loss and postpartum hemorrhage (PPH) have not been adequately evaluated. We sought to compare postpartum blood loss and PPH in African American and Hispanic parturients compared to other groups.This was a secondary analysis of an observational study at a tertiary academic center of a historical (August 2016 to January 2017) and interventional (August 2017 to January 2018) cohort of 7618 deliveries. Visual estimation of blood loss (EBL) was used in the historical group and quantitative blood loss (QBL) was implemented in the intervention group. Our primary endpoint was median blood loss in African Americans versus other racial groups between cohorts.A total of 7618 deliveries were evaluated; 755 (9.9%) were identified as African American with 1035 (13.6%) identifying as Hispanic. Blood loss was similar in racial groups using EBL (p=0.131), but not QBL that was 430 (227-771) in African Americans and 348 (200-612) in non-African Americans (p<0.001). PPH was greater among African Americans in both groups (10.3% vs. 6.9% in EBL cohort, p=0.023, and 16.9% vs. 11.6% in QBL cohort, p<0.001).Racial and ethnic differences in peripartum blood loss were more apparent with QBL than EBL. It is unknown if these differences are caused by provider cognitive bias, socioeconomic differences, language barriers and/or other factors.

    View details for DOI 10.7759/cureus.25299

    View details for PubMedID 35755558

    View details for PubMedCentralID PMC9225058

  • Development and validation of a Portuguese version of Obstetric Quality of Recovery-10 (ObsQoR-10-Portuguese). Anaesthesia, critical care & pain medicine Mathias, L., Carlos, R. V., Siaulys, M., Gabriades, P., Guo, N., Domingue, B., O'Carroll, J., Carvalho, B., Sultan, P. 2022: 101085

    Abstract

    BACKGROUND: We aimed to develop and validate a Portuguese version of the Obstetric Quality of Recovery-10 (ObsQoR-10-Portuguese) patient-reported outcome measure and evaluate its psychometric properties.METHODS: After ethical approval, we recruited term pregnant women undergoing uncomplicated elective cesarean delivery in a single Brazilian institution. Women were invited to complete the translated ObsQoR-10-Portuguese and EuroQoL (EQ-5D) questionnaires (including a global health visual analog scale [GHVAS]) at 24hours (±6hours) following delivery, and a subset of women an hour later. We assessed validity and reliability of ObsQoR-10-Portuguese.RESULTS: One hundred thirteen and 29 enrolled women completed the surveys at 24h and 25h (100% response rate).VALIDITY: (i) Convergent validity: ObsQoR-10-Portuguese correlated moderately with EuroQoL score (r=-0.587) and GHVAS score (r=0.568) at 24h. (ii) Discriminant validity: ObsQoR-10 discriminated well between good versus poor recovery (GHVAS score ≥ 70 versus < 70; difference in mean scores 14.2; p<0.001). (iii) Hypothesis testing: 24-h ObsQoR-10-Portuguese scores correlated with gestational age (r=0.191; p=0.043). (iv) Cross-cultural validity: Differential item functioning analysis suggested bias in 2 items. Reliability: (i) Internal consistency was good (Cronbach's alpha=0.82 and inter-item correlation=0.31). (ii) Split-half reliability was very good (Spearman-Brown Prophesy Reliability Estimate=0.80). (iii) Test re-test reliability was excellent (intra-class correlation coefficient=0.87). (iv) Floor and ceiling effects: <5% women scored either 0 or 100 (lowest and highest scores, respectively).CONCLUSION: ObsQoR-10-Portuguese is valid and reliable, and should be considered for use in Portuguese-speaking women to assess their quality of inpatient recovery following cesarean delivery.

    View details for DOI 10.1016/j.accpm.2022.101085

    View details for PubMedID 35487408

  • Calcium chloride for the prevention of uterine atony during cesarean delivery: A pilot randomized controlled trial and pharmacokinetic study. Journal of clinical anesthesia Ansari, J. R., Kalariya, N., Carvalho, B., Flood, P., Guo, N., Riley, E. 2022; 80: 110796

    Abstract

    To assess the feasibility, patient tolerance, pharmacokinetics, and potential effectiveness of a randomized controlled trial protocol investigating intravenous calcium chloride for the prevention of uterine atony during cesarean delivery.Double-blind, randomized controlled pilot trial with nested population pharmacokinetic analysis.This study was performed at Lucile Packard Children's Hospital, from August 2018 to September 2019.Forty patients with at least two risk factors for uterine atony at the time of cesarean delivery.One gram of intravenous calcium chloride (n = 20 patients) or a saline placebo control (n = 20 patients), in addition to standard care with oxytocin, upon umbilical cord clamping.The primary efficacy-related outcome was the presence of uterine atony defined as the use of a second-line uterotonic medication, surgical interventions for atony, or hemorrhage with blood loss >1000 mL. Blood loss, uterine tone numerical rating scores, serial venous blood calcium levels, hemodynamics, and potential side effects were also assessed.The study protocol proved feasible. The incidence of atony was 20% in parturients who received calcium compared to 50% in the placebo group (relative risk 0.38, P = 0.07, 95% CI 0.15-1.07, NNT 3.3). Calcium recipients tolerated the drug infusion well, with no adverse events and an equal incidence of potential side effects in the calcium and placebo groups. Ionized calcium concentration rose significantly in all patients who received calcium infusion, from baseline 1.18 mmol/L to peak levels 1.50-1.60 mmol/L. One-compartment population pharmacokinetics established clearance of 0.93 (95% CI 0.63-1.52) L/min and volume of distribution 76 (95% CI 49-94) L.In this pilot study, investigators found that intravenous calcium chloride was well-tolerated by the 20 patients assigned to receive the study drug and may be effective in prevention of uterine atony. A 1-g dose was sufficient to substantially increase calcium levels without any critically elevated lab values or concern for adverse side effects. These encouraging findings warrant further investigation of calcium as a novel agent to prevent uterine atony with an adequately powered clinical trial. Clinical trial registry NCT03867383 https://clinicaltrials.gov/ct2/show/NCT03867383.

    View details for DOI 10.1016/j.jclinane.2022.110796

    View details for PubMedID 35447502

  • Cardiac ultrasonography in obstetrics - a necessary skill for the present and future anesthesiologist. International journal of obstetric anesthesia Ortner, C. M., Padilla, C., Carvalho, B. 2022; 50: 103545

    View details for DOI 10.1016/j.ijoa.2022.103545

    View details for PubMedID 35381420

  • Accuracy of visual estimation of blood loss in obstetrics using clinical reconstructions: an observational simulation cohort study. International journal of obstetric anesthesia Athar, M. W., Abir, G., Seay, R. C., Guo, N., Butwick, A., Carvalho, B. 2022; 50: 103539

    Abstract

    INTRODUCTION: Postpartum hemorrhage is the leading cause of maternal mortality worldwide, and optimal management requires accurate blood loss estimations. The aim of this study was to assess whether differences exist between visually estimated blood loss versus actual blood loss based on delivery mode, blood volume or distribution/location and knowledge of patient's current cardiovascular status.METHODS: For this observational cohort study, photographs were taken of 18 blood loss scenarios for vaginal delivery and cesarean delivery, and six photographs were duplicated and annotated with maternal vital signs. Scenarios were categorized into 50% (500 mL), 100% (1000 mL) and 200% (2000 mL) of the defined blood loss volume for postpartum hemorrhage and the photographs were shown to participants to visually estimate blood loss volumes.RESULTS: The mean ± standard deviation estimates of actual 500 mL, 1000 mL and 2000 mL blood loss volumes were 1208 ± 438 mL, 1676 ± 630 mL and 2637 ± 1123 mL, respectively (P <0.001 among groups). The difference was significantly greater in vaginal delivery than cesarean delivery scenarios (1064 ± 849 mL vs. 284 ± 456 mL; P <0.001). Estimated blood loss volume was not influenced by blood loss distribution/location, or by provider group or experience. The cardiovascular status of the patient impacted estimations only if tachycardia and hypotension were present.CONCLUSIONS: Most providers significantly overestimated blood loss volumes (by nearly 700 mL). Provider and scenario factors that impact inaccuracies in visual estimated blood loss identified in this study can be used to guide education and training.

    View details for DOI 10.1016/j.ijoa.2022.103539

    View details for PubMedID 35397264

  • In-Hospital Opioid Consumption After the Previous Cesarean Delivery Weakly Predicts Opioid Consumption After Index Delivery: A Retrospective Cohort Study. Anesthesia and analgesia Komatsu, R., Nash, M., Mandalia, S., Dinges, E., Kamal, U., Singh, D., El-Omrani, H., Anwar, A., Delgado, C., Ziga, T. M., Carvalho, B. 2022

    Abstract

    BACKGROUND: To predict opioid consumption and pain intensity after the index cesarean delivery, we tested a hypothesis that opioid consumption after the previous cesarean delivery of the same patient can predict the opioid consumption after the index cesarean delivery. We further tested a secondary hypothesis that the pain scores after the previous cesarean delivery can predict the pain scores after the index cesarean delivery.METHODS: This is a retrospective cohort study of 470 women who underwent both previous and index cesarean deliveries at a single institution from January 2011 to June 2019. To predict the opioid consumption (primary outcome) and average pain scores (on 11-point numeric rating scale) after their index cesarean delivery, we used a linear regression model incorporating only the opioid consumption and average pain scores after the previous cesarean delivery, respectively (unadjusted models). Demographic and obstetric variables were then added as predictors (adjusted models). The bootstrap was used to compare these models with respect to proportion of variance of the outcome accounted for (R2).RESULTS: Unadjusted models were weakly predictive of opioid consumption (R2 = 0.268; 95% confidence interval [CI], 0.146-0.368) and average pain scores (R2 = 0.176; 95% CI, 0.057-0.250). An adjusted model for opioid consumption was weakly predictive (R2 = 0.363; 95% CI, 0.208-0.478), but an adjusted model for average pain scores was not predictive of the outcomes (R2 = 0.070; 95% CI, -0.143 to 0.219). Adjusted models failed to explain variances of opioid consumption and average pain scores significantly better than unadjusted models (P = .099 and P = .141, respectively).CONCLUSIONS: Opioid consumption and pain scores after women's previous cesarean delivery only explain 27% of variance of opioid consumption and 18% of variance of their pain after their index cesarean delivery. Therefore, previous cesarean delivery analgesic metrics are not robust enough to be used as clinically applicable predictors for index delivery.

    View details for DOI 10.1213/ANE.0000000000005918

    View details for PubMedID 35130195

  • World Health Organization Recommendation for Using Uterine Balloon Tamponade to Treat Postpartum Hemorrhage. Obstetrics and gynecology Weeks, A. D., Akinola, O. I., Amorim, M., Carvalho, B., Deneux-Tharaux, C., Liabsuetrakul, T., Meremikwu, M., Miller, S., Nabhan, A., Nagai, M., Wahabi, H., Walker, D. 1800

    Abstract

    The World Health Organization (WHO) recently published a new recommendation on the use of the uterine balloon tamponade for the treatment of postpartum hemorrhage. The recommendation that uterine balloon tamponade should be used only where there is already access to other postpartum hemorrhage treatments (including immediate recourse to surgery) has proved controversial. It is especially problematic for those working in low-level health care facilities in under-resourced settings, where there are already programs that have introduced low-cost uterine balloon tamponade devices for use, even in settings where recourse to surgical interventions is not possible. However, there are now two separate randomized trials that both unexpectedly show unfavorable outcomes in these settings when a condom catheter uterine balloon tamponade device was introduced. Considering the balance of potential benefits and these safety concerns, the WHO postpartum hemorrhage guideline panel therefore recommends that uterine balloon tamponade should be used only in contexts where other supportive postpartum hemorrhage interventions are available if needed.

    View details for DOI 10.1097/AOG.0000000000004674

    View details for PubMedID 35115478

  • Patient Preferences for Outcomes Associated With Labor Epidural Analgesia. Cureus Harding, A., George, R. B., Munro, A., Coolen, J., Snelgrove-Clarke, E., Carvalho, B. 2022; 14 (2): e22599

    Abstract

    Purpose Patient preferences for labor epidural analgesia (LEA) have been incompletely evaluated. This study aimed to determine the importance of various LEA outcomes to both antenatal and postpartum patients. Methods This was a cross-sectional study approved by the institutional ethics board. Questionnaires were distributed to two separate and distinct cohorts screened for eligibility: pregnant patients at an antenatal visit and postpartum patients during childbirth admission. A list of common LEA outcomes was compiled using research published in leading anesthesia journals. Participants ranked the outcomes according to perceived importance. They assigned each a number from 1 to 10 (priority ranking; 1 indicated the highest priority outcome and 10 the least). They were also asked to 'spend' $100 towards the outcomes (relative value scale), allocating more money to outcomes more important to them. Results Two hundred twentyquestionnaires were completed (105 antenatal, 115 postpartum). 'Achieving desired pain relief' was the most important outcome for both cohorts. It was valued more by the postpartum cohort (Median $50 (25 - 60) vs $30 (18 - 50)). 'Overall satisfaction with the pain management,''experiencing a short time to achieve pain relief,'and 'experiencing a short duration of labor' received more money than avoiding various LEA-related side effects. The postpartum cohort ranked 'experiencing a short time to achieve pain relief' as more important than the antenatal cohort (Median 5 (3 - 7) vs 3 (2 - 5)). Conclusions Achieving the desired pain relief was the highest LEA outcome preference for both antenatal and postpartum patients. Avoiding side effects was less important relative to pain-related outcomes.

    View details for DOI 10.7759/cureus.22599

    View details for PubMedID 35355544

  • Un sondage sur les pratiques de peridurales pour le travail dans les programmes de fellowship en anesthesie obstetricale aux Etats-Unis. Canadian journal of anaesthesia = Journal canadien d'anesthesie Callahan, E., Yeh, P., Carvalho, B., George, R. B. 1800

    Abstract

    PURPOSE: Labour epidural analgesia (LEA) is an evolving field. Various neuraxial techniques and dosing regimens are available to the modern obstetric anesthesia provider, allowing for significant practice variability. To begin a search for consensus on optimal care, we sought to query fellowship training practices for LEA.METHODS: We conducted an electronic survey of institutions with American Council for Graduate Medical Education-accredited obstetric anesthesiology fellowship programs. We studied the frequency of epidural initiation techniques, including combined spinal epidural (CSE), dural puncture epidural, and epidural bolus. For maintenance techniques, we appraised the use of continuous epidural infusion, programmed intermittent bolus (PIEB), and patient-controlled epidural analgesia (PCEA).RESULTS: Of 40 institutions surveyed, we received 32 responses (80% response rate). Twenty-eight of 40 (70%) were included in the analysis. A plurality of institutions (12/28; 43%) preferred CSE, and among those who used CSE, 23/27 (85%) included intrathecal opioids. A majority of institutions used protocols with PIEB (55%), while almost all (92%) used PCEA. Most participants (88%) reported using dilute concentration maintenance infusions of 0.1% bupivacaine/ropivacaine or less.CONCLUSION: Despite significant variability in LEA practice, some clear patterns emerged in our survey, including preference for opioid-containing CSE and maintenance with PIEB, PCEA, and dilute epidural solutions.

    View details for DOI 10.1007/s12630-022-02192-6

    View details for PubMedID 35089544

  • Quantitative blood loss after vaginal delivery: a retrospective analysis of 104 079 measurements at 41 institutions. International journal of obstetric anesthesia Ansari, J., Farber, M. K., Thurer, R. L., Guo, N., Rubenstein, A., Carvalho, B. 2022; 51: 103256

    Abstract

    BACKGROUND: Peripartum quantitative blood loss (QBL) measurement is recommended over visual estimation. However, QBL measurement after vaginal delivery has been inadequately evaluated. The primary aim of this study was to determine the characteristics of QBL measurements from a large, multicenter cohort of patients having vaginal deliveries. We also determined the incidence of postpartum hemorrhage (PPH) and the relationship between gravimetric QBL from weighed sponges vs. volumetric QBL from liquid drape or suction cannister contents.METHODS: Data were collected from 41 institutions in the United States of America that use an automated QBL device after vaginal delivery as part of routine care. The QBL device tracks cumulative blood loss based on gravimetry and volumetric V-drape assessment, automatically subtracting the dry weights of all blood-containing sponges, towels, pads and other supplies as well as the amniotic fluid volume.RESULTS: Between January 2017 and April 2020, 104 079 QBL values were obtained from patients having vaginal deliveries. Total median [IQR] QBL was 171 [61-362] mL. The PPH incidence, stratified by QBL, was 15.2% (>500 mL), 3.4% (>1000 mL), and 1.0% (>1500 mL). The contribution of QBL from V-drapes was 60.6±26.3% of total QBL.CONCLUSION: The results from this large set of QBL measurements and the PPH incidence provide normative "real-world" clinical care values that can be expected as hospitals transition from EBL to QBL to assess the blood loss of women having vaginal delivery.

    View details for DOI 10.1016/j.ijoa.2022.103256

    View details for PubMedID 35636143

  • Limitations of Gravimetric Quantitative Blood Loss during Cesarean Delivery AJP REPORTS Thurer, R. L., Doctorvaladan, S., Carvalho, B., Jelks, A. T. 2022; 12 (01): E36-E40

    Abstract

    Objective  This study examined the accuracy, sources of error, and limitations of gravimetric quantification of blood loss (QBL) during cesarean delivery. Study Design  Blood loss determined by assays of the hemoglobin content on surgical sponges and in suction canisters was compared with QBL in 50 parturients. Results  QBL was moderately correlated to the actual blood loss ( r  = 0.564; p  < 0.001). Compared with the reference assay, QBL overestimated blood loss for 44 patients (88%). QBL deviated from the assayed blood loss by more than 250 mL in 34 patients (68%) and by more than 500 mL in 16 cases (32%). Assayed blood loss was more than 1,000 mL in four patients. For three of these patients, QBL was more than 1,000 mL (sensitivity = 75%). QBL was more than 1,000 mL in 12 patients. While three of these had an assayed blood loss of more than 1,000 mL, 9 of the 46 patients with blood losses of less than 1,000 mL by the assay (20%) were incorrectly identified as having postpartum hemorrhage by QBL (false positives). The specificity of quantitative QBL for detection of blood loss more than or equal to 1,000 mL was 80.4%. Conclusion  QBL was only moderately correlated with the reference assay. While overestimation was more common than underestimation, both occurred. Moreover, QBL was particularly inaccurate when substantial bleeding occurred. Key Points QBL is inaccurate in cesarean delivery.QBL deviated from the assay result by more than 500 mL in 32% of cases.QBL sensitivity and specificity for hemorrhage is 75.0% (95% confidence interval [CI]: 0.19-0.93) and 80.4% (95% CI: 0.69-0.92), respectively.

    View details for DOI 10.1055/s-0041-1742267

    View details for Web of Science ID 000751029800005

    View details for PubMedID 35141034

    View details for PubMedCentralID PMC8816625

  • Magnesium sulfate pharmacokinetics after intramuscular dosing in women with preeclampsia. AJOG global reports Brookfield, K., Galadanci, H., Du, L., Wenning, L., Mohammed, I., Suleiman, M., Oladapo, O. T., Witjes, H., Carvalho, B. 2021; 1 (4): 100018

    Abstract

    BACKGROUND: Current intramuscular magnesium dosing regimens in low and middle-income countries are based on indirect absorption parameters to inform pharmacokinetic and pharmacodynamic response.OBJECTIVE: To determine if therapeutic serum magnesium levels are obtained in women with severe preeclampsia receiving intramuscular administration of magnesium sulfate using the Pritchard regimen and to compare the key pharmacokinetic variables to those previously published.STUDY DESIGN: Serum magnesium levels were obtained at multiple time points at baseline and after magnesium sulfate administration from women with severe preeclampsia receiving the standard Pritchard regimen for seizure prophylaxis at Bayero University, Kano, Nigeria. The pharmacokinetic profiles were constructed for the study cohort and the updated pharmacokinetic model was compared with the one that was previously published.RESULTS: A total of 80 blood samples were collected from 20 women with severe preeclampsia (45 collected before childbirth and 35 collected after childbirth). After 11.5 hours of magnesium sulfate administration, 63% of women in the cohort had serum magnesium levels of ≥2.0 mmol/L. Data from women receiving the Pritchard regimen combined with data from women previously modeled after the receipt of intravenous magnesium sulfate were adequately described using a 2-compartment model with first-order absorption and linear elimination from the central compartment. All structural pharmacokinetic parameters including clearance, central volume of distribution, peripheral volume of distribution, and intercompartment clearance were adjusted for maternal weight, and the clearance was further adjusted for serum creatinine level and antepartum or postpartum status. The simulated pharmacokinetic profiles of the updated pharmacokinetic model and the previously published pharmacokinetic model are similar. In previously published pharmacokinetic modeling, absorption rate constant=0.32 and absolute bioavailability=0.86. In the updated pharmacokinetic model, absorption rate constant=0.45 and absolute bioavailability=0.91.CONCLUSION: These data support the use of the Pritchard regimen as acceptable to achieve therapeutic serum magnesium levels and support the reported simulation of serum magnesium levels and eclampsia response associated with different intramuscular regimens.

    View details for DOI 10.1016/j.xagr.2021.100018

    View details for PubMedID 36277458

  • A randomized trial to investigate needle redirections/re-insertions using a handheld ultrasound device versus traditional palpation for spinal anesthesia in obese women undergoing cesarean delivery. International journal of obstetric anesthesia Weiniger, C. F., Carvalho, B., Ronel, I., Greenberger, C., Aptekman, B., Almog, O., Kagan, G., Shalev, S. 2021: 103229

    Abstract

    BACKGROUND: Ultrasound may be useful to identify the spinal anesthesia insertion point, particularly when landmarks are not palpable. We tested the hypothesis that the number of needle redirections/re-insertions is lower when using a handheld ultrasound device compared with palpation in obese women undergoing spinal anesthesia for cesarean delivery.METHODS: Study recruits were obese (body mass index (BMI) >30 kg/m2) women with impalpable bony landmarks who were undergoing spinal anesthesia for elective cesarean delivery. Women were randomized to ultrasound or palpation. The primary study outcome was a composite between-group comparison of total number of needle redirections (any withdrawal and re-advancement of the needle and/or introducer within the intervertebral space) or re-insertions (any new skin puncture in the same or different intervertebral space) per patient. Secondary outcomes included insertion site identification time and patient verbal numerical pain score (0-10) for comfort during surgical skin incision.RESULTS: Forty women completed the study. The mean BMI (standard deviation) for the ultrasound group was 39.8 (5.5) kg/m2 and for the palpation group 37.3 (5.2) kg/m2. There was no difference in the composite primary outcome (median (interquartile range) [range]) between the ultrasound group (4 (2-13) [2-22]) and the (6 (4-10) [1-17]) palpation group (P=0.22), with the 95% confidence interval of the difference 2 (-1.7 to 5.7). There were no differences in the secondary outcomes.CONCLUSIONS: Handheld ultrasound did not demonstrate any advantages over traditional palpation techniques for spinal anesthesia in an obese population undergoing cesarean delivery, although the study was underpowered to show a difference.

    View details for DOI 10.1016/j.ijoa.2021.103229

    View details for PubMedID 34670725

  • Impact of enhanced recovery after caesarean delivery on maternal outcomes: A systematic review and meta-analysis. Anaesthesia, critical care & pain medicine Pervez, S., Sharawi, N., Blake, L., Habib, A. S., Brookfield, K. F., Carvalho, B. 2021: 100935

    Abstract

    BACKGROUND: This meta-analysis explores the impact of enhanced recovery after caesarean delivery (ERAC) on maternal outcomes.METHODS: We searched 4 databases (Web of Science, Embase, PubMed and CINAHL) in October 2020 without date limiters for studies quantitatively comparing ERAC implementation to a control group. The primary outcome was length of hospital stay and secondary outcomes included time to mobilization and time to urinary catheter removal, opioid consumption, readmission rates and cost savings. Mean differences and odds ratios (MD and OR with 95% confidence intervals) were calculated. Level of evidence was assessed using GRADE.RESULTS: Twelve studies involving 17,607 patients (9,693 without ERAC and 7,914 with ERAC) were included. ERAC was associated with reduced: length of hospital stay (MD -0.51 days [-0.94, -0.09]; p = 0.018; I2 = 99%), time to first mobilization (MD -11.05hours [-18.64, -3.46]; p = 0.004; I2 = 98%), time to urinary catheter removal (MD -13.19hours [-17.59, -8.79]; p < 0.001; I2 = 97% and opioid consumption (MD -21.85mg morphine equivalents [-33.19, -10.50]; p = < 0.001; I2 = 91%), with no difference in maternal readmission rate (OR 1.23 [0.96, 1.57]; p = 0.10; I2 = 0%). Three studies reported cost savings associated with ERAC. The GRADE level of evidence was rated as low or very low quality for all study outcomes.CONCLUSION: ERAC is associated with reduction in length of stay, times to first mobilization and urinary catheter removal and opioid consumption. ERAC does not significantly affect maternal hospital readmission rates following discharge. Further studies are required to determine which ERAC interventions to implement and which outcomes best determine ERAC efficacy.

    View details for DOI 10.1016/j.accpm.2021.100935

    View details for PubMedID 34390864

  • Evidence-based guidance for use of intrathecal morphine as an alternative to diamorphine for Caesarean delivery analgesia. British journal of anaesthesia Sultan, P., Carvalho, B. 2021

    Abstract

    Intrathecal morphine in combination with fentanyl is an effective and safe alternative to diamorphine for Caesarean delivery analgesia. Evidence suggests minimal differences in clinical efficacy and side-effects between intrathecal morphine and diamorphine. Recommended intrathecal morphine doses for Caesarean delivery analgesia are 100-150 ug.

    View details for DOI 10.1016/j.bja.2021.06.023

    View details for PubMedID 34362559

  • Estimating Obstetric Anaesthesia Workload: Number of Deliveries Compared to Time-Based Workload. Turkish journal of anaesthesiology and reanimation Kowalczyk, J. J., Lipman, S. S., Carvalho, B. 2021; 49 (4): 292-297

    Abstract

    Number of deliveries is utilised to estimate obstetric anaesthesiologist workload; however, this may not reflect true workload. The goal of this analysis was to assess if including type of procedure, time required and length of each shift would better predict clinical workloads.We queried the electronic medical records at a high volume, academic centre for 12 consecutive months of maternal deliveries. Data extracted included delivery type, analgesic/anaesthetic procedure and whether delivery occurred during weekday, weeknight or weekend shifts. To generate an hourly comparison of shifts of varying duration, procedures were divided by the number of hours per shift. To calculate obstetric anaesthesiology time-based workload, delivery type was multiplied by estimated time associated with the analgesic/anaesthetic procedure.A total of 4,598 deliveries occurred in the 12-month study period. The caesarean delivery rate was 32%, and labour epidural rate was 85%. 1,564 anaesthetic procedures occurred during weekdays and 2,557 occurred during the weeknights and weekends. After accounting for the duration of each procedure and hours per shift, mean 6 standard deviation time-based workload ratio was 0.68 6 0.12 on weekdays versus 0.36 6 0.07 on weeknights and weekends.Relative workload based on deliveries alone suggests 41% less workload during the weekday, whereas accounting for duration of each procedure and hours per shift resulted in an 89% greater workload on weekday shifts. The study highlights the importance of considering analgesic/anaesthetic procedures and estimates of time taken to perform them, not just number of deliveries when considering obstetric anaesthesiology workload.

    View details for DOI 10.5152/TJAR.2021.924

    View details for PubMedID 35110010

  • Estimating Obstetric Anaesthesia Workload: Number of Deliveries Compared to Time-Based Workload TURKISH JOURNAL OF ANAESTHESIOLOGY AND REANIMATION Kowalczyk, J. J., Lipman, S. S., Carvalho, B. 2021; 49 (4): 292-297
  • Standardizing nomenclature in regional anesthesia: an ASRA-ESRA Delphi consensus study of abdominal wall, paraspinal, and chest wall blocks. Regional anesthesia and pain medicine El-Boghdadly, K., Wolmarans, M., Stengel, A. D., Albrecht, E., Chin, K. J., Elsharkawy, H., Kopp, S., Mariano, E. R., Xu, J. L., Adhikary, S., Altiparmak, B., Barrington, M. J., Bloc, S., Blanco, R., Boretsky, K., Borglum, J., Breebaart, M., Burckett-St Laurent, D., Capdevila, X., Carvalho, B., Chuan, A., Coppens, S., Costache, I., Dam, M., Egeler, C., Fajardo, M., Gadsden, J., Gautier, P. E., Grant, S. A., Hadzic, A., Hebbard, P., Hernandez, N., Hogg, R., Holtz, M., Johnson, R. L., Karmakar, M. K., Kessler, P., Kwofie, K., Lobo, C., Ludwin, D., MacFarlane, A., McDonnell, J., McLeod, G., Merjavy, P., Moran, E., O'Donnell, B. D., Parras, T., Pawa, A., Perlas, A., Rojas Gomez, M. F., Sala-Blanch, X., Saporito, A., Sinha, S. K., Soffin, E. M., Thottungal, A., Tsui, B. C., Tulgar, S., Turbitt, L., Uppal, V., van Geffen, G. J., Volk, T., Elkassabany, N. M. 2021; 46 (7): 571-580

    Abstract

    BACKGROUND: There is heterogeneity in the names and anatomical descriptions of regional anesthetic techniques. This may have adverse consequences on education, research, and implementation into clinical practice. We aimed to produce standardized nomenclature for abdominal wall, paraspinal, and chest wall regional anesthetic techniques.METHODS: We conducted an international consensus study involving experts using a three-round Delphi method to produce a list of names and corresponding descriptions of anatomical targets. After long-list formulation by a Steering Committee, the first and second rounds involved anonymous electronic voting and commenting, with the third round involving a virtual round table discussion aiming to achieve consensus on items that had yet to achieve it. Novel names were presented where required for anatomical clarity and harmonization. Strong consensus was defined as ≥75% agreement and weak consensus as 50% to 74% agreement.RESULTS: Sixty expert Collaborators participated in this study. After three rounds and clarification, harmonization, and introduction of novel nomenclature, strong consensus was achieved for the names of 16 block names and weak consensus for four names. For anatomical descriptions, strong consensus was achieved for 19 blocks and weak consensus was achieved for one approach. Several areas requiring further research were identified.CONCLUSIONS: Harmonization and standardization of nomenclature may improve education, research, and ultimately patient care. We present the first international consensus on nomenclature and anatomical descriptions of blocks of the abdominal wall, chest wall, and paraspinal blocks. We recommend using the consensus results in academic and clinical practice.

    View details for DOI 10.1136/rapm-2020-102451

    View details for PubMedID 34145070

  • Integrated trajectories of the maternal metabolome, proteome, and immunome predict labor onset. Science translational medicine Stelzer, I. A., Ghaemi, M. S., Han, X., Ando, K., Hedou, J. J., Feyaerts, D., Peterson, L. S., Rumer, K. K., Tsai, E. S., Ganio, E. A., Gaudilliere, D. K., Tsai, A. S., Choisy, B., Gaigne, L. P., Verdonk, F., Jacobsen, D., Gavasso, S., Traber, G. M., Ellenberger, M., Stanley, N., Becker, M., Culos, A., Fallahzadeh, R., Wong, R. J., Darmstadt, G. L., Druzin, M. L., Winn, V. D., Gibbs, R. S., Ling, X. B., Sylvester, K., Carvalho, B., Snyder, M. P., Shaw, G. M., Stevenson, D. K., Contrepois, K., Angst, M. S., Aghaeepour, N., Gaudilliere, B. 2021; 13 (592)

    Abstract

    Estimating the time of delivery is of high clinical importance because pre- and postterm deviations are associated with complications for the mother and her offspring. However, current estimations are inaccurate. As pregnancy progresses toward labor, major transitions occur in fetomaternal immune, metabolic, and endocrine systems that culminate in birth. The comprehensive characterization of maternal biology that precedes labor is key to understanding these physiological transitions and identifying predictive biomarkers of delivery. Here, a longitudinal study was conducted in 63 women who went into labor spontaneously. More than 7000 plasma analytes and peripheral immune cell responses were analyzed using untargeted mass spectrometry, aptamer-based proteomic technology, and single-cell mass cytometry in serial blood samples collected during the last 100 days of pregnancy. The high-dimensional dataset was integrated into a multiomic model that predicted the time to spontaneous labor [R = 0.85, 95% confidence interval (CI) [0.79 to 0.89], P = 1.2 * 10-40, N = 53, training set; R = 0.81, 95% CI [0.61 to 0.91], P = 3.9 * 10-7, N = 10, independent test set]. Coordinated alterations in maternal metabolome, proteome, and immunome marked a molecular shift from pregnancy maintenance to prelabor biology 2 to 4 weeks before delivery. A surge in steroid hormone metabolites and interleukin-1 receptor type 4 that preceded labor coincided with a switch from immune activation to regulation of inflammatory responses. Our study lays the groundwork for developing blood-based methods for predicting the day of labor, anchored in mechanisms shared in preterm and term pregnancies.

    View details for DOI 10.1126/scitranslmed.abd9898

    View details for PubMedID 33952678

  • Intravenous oxytocin dosing regimens for postpartum hemorrhage prevention at cesarean section: a systematic review and meta-analysis. American journal of obstetrics and gynecology Phung, L. C., Farrington, E. K., Connolly, M., Wilson, A. N., Carvalho, B., Homer, C. S., Vogel, J. P. 2021

    Abstract

    OBJECTIVE: To synthesize available evidence on intravenous (IV) oxytocin dosing regimens for the prevention of postpartum hemorrhage (PPH) at cesarean section (CS).DATA SOURCES: We searched Medline/OVID, Embase, Global Index Medicus, CINAHL, CENTRAL, ClinicalTrials.gov, and ICTRP for eligible studies published until Feb 2020.STUDY ELIGIBILITY CRITERIA: We included any randomized or non-randomized study published in peer-reviewed journals that compared at least two different dosing regimens of IV oxytocin for PPH prevention in women undergoing CS.STUDY APPRAISAL AND SYNTHESIS METHODS: Two authors independently assessed eligibility, extracted data, and assessed risk of bias. Primary outcome was incidence of PPH ≥ 1000 mL. Other review outcomes included use of additional uterotonics, blood loss, and adverse maternal events. Data were analyzed based on type of IV administration (bolus only, infusion only, bolus plus infusion) and oxytocin dose. Meta-analysis was performed using randomized trials and reported using risk ratios or mean difference with 95% confidence intervals. GRADE was used to rate the certainty of evidence. Findings from dose-finding trials and non-randomized studies were reported narratively.RESULTS: Thirty-five studies (7,333 women) met our inclusion criteria, including 30 randomized trials and five non-randomized studies. There were limited data from trials for most outcomes, and results were not conclusive. Compared to bolus plus infusion regimens, bolus only regimens probably result in slightly higher mean blood loss (MD 52 mL, 95% CI 0.4-104 mL, moderate certainty). Amongst bolus plus infusion regimens, initial bolus doses < 5 IU may reduce nausea (RR 0.26, 95% CI 0.11-0.63, low certainty) as compared to 5-9 IU. Total oxytocin doses 5-9 IU versus 10-19 IU may increase use of additional uterotonics (RR 13.00, 95% CI 1.75-96.37, low certainty). Effects on other outcomes were generally inconclusive.CONCLUSION: There are limited data comparing IV oxytocin regimens for PPH prevention at CS. Bolus plus infusion regimens may lead to minor reductions in mean blood loss, and initial bolus doses of < 5 IU may minimize nausea. Bolus only regimens of 10 IU versus 5 IU may decrease use of additional uterotonics, however further comparative trials are required to understand effects on other key outcomes, particularly hypotension.

    View details for DOI 10.1016/j.ajog.2021.04.258

    View details for PubMedID 33957113

  • An observational pilot study of a novel loss of resistance syringe for locating the epidural space. International journal of obstetric anesthesia Athar, M. W., Guo, N., Ortner, C., Carvalho, B., Abir, G., Riley, E. T. 2021: 102984

    Abstract

    BACKGROUND: The EpiFaith syringe is a novel loss-of-resistance syringe that utilizes a spring-loaded plunger that automatically moves forward within the syringe when there is a loss of resistance. We evaluated the syringe in a clinical setting, among a cohort of pregnant women receiving neuraxial labor analgesia.METHODS: In a non-randomized, observational study, four anesthesiologists used the EpiFaith syringe 10 times each while placing epidural catheters for labor analgesia. The anesthesiologists scored each placement on an 11-point Likert scale (-5 = absolutely worse, 0 = the same, and 5 = absolutely better than using their regular loss-of-resistance syringe technique).RESULTS: All 40 neuraxial placements correctly located the epidural space. Air was used in the syringe in 35 of the 40 cases. In 50%, 27.5% and 22.5% of cases the anesthesiologists reported that using the EpiFaith syringe was better than, the same as, or worse than using their regular syringe, respectively. There were no inadvertent dural punctures.CONCLUSIONS: This feasibility study found that three of the four anesthesiologists scored the EpiFaith syringe as better or the same as using their regular loss-of-resistance syringe. More extensive studies are required to determine if the EpiFaith syringe reduces adverse outcomes such as unintentional dural punctures.

    View details for DOI 10.1016/j.ijoa.2021.102984

    View details for PubMedID 33994273

  • Superficial Cervical Plexus Block for Awake Large-Bore Central Line Placement in Parturients: A Case Series. A&A practice Sheikh, M., Carvalho, B., Boublik, J., Ansari, J. 2021; 15 (3): e01429

    Abstract

    Pregnant patients with high-risk conditions including abnormal placentation or severe cardiovascular disease may require large-bore central venous access at the time of delivery. Central lines are generally inserted while obstetric patients are awake, either because neuraxial anesthesia is planned or to minimize fetal exposure to anesthetic medications. Despite local infiltration, the procedure can cause significant patient discomfort. This case series describes use of a superficial cervical plexus block (SCPB) to facilitate line placement in 4 pregnant women with high-risk conditions. SCPB is technically straightforward with low reported complication rates and should be considered for pregnant patients requiring large-bore central lines.

    View details for DOI 10.1213/XAA.0000000000001429

    View details for PubMedID 33740791

  • Point-of-Care Lung Ultrasound Pattern in Healthy Parturients: Prevalence of Pulmonary Interstitial Syndrome Following Vaginal Delivery, Elective and Unplanned Intrapartum Cesarean Delivery. Anesthesia and analgesia Macias, P. n., Wilson, J. G., Austin, N. S., Guo, N. n., Carvalho, B. n., Ortner, C. M. 2021

    Abstract

    Pregnancy-related cardiovascular physiologic changes increase the likelihood of pulmonary edema, with the risk of fluid extravasating into the pulmonary interstitium being potentially at a maximum during the early postpartum period. Data on the impact of labor and peripartum hemodynamic strain on lung ultrasound (LUS) are limited, and the prevalence of subclinical pulmonary interstitial syndrome in peripartum women is poorly described. The primary aim of this exploratory study was to estimate the prevalence of pulmonary interstitial syndrome in healthy term parturients undergoing vaginal (VD), elective (eCD), and unplanned intrapartum cesarean deliveries (uCD). Secondary aims were to estimate the prevalence of positive lung regions (≥3 B-lines on LUS per region) and to assess the associations between positive lung regions and possible contributing factors.In this prospective observational cohort study, healthy women at term undergoing VD, eCD, or uCD were enrolled. Following international consensus recommendations, a LUS examination was performed within 4 hours after delivery applying an 8-region technique. Pulmonary interstitial syndrome was defined by the presence of 2 or more positive lung regions per hemithorax. Ultrasound studies were reviewed by 2 blinded reviewers and assessed for interobserver reliability.Seventy-five women were assessed (n = 25 per group). No pulmonary interstitial syndrome was found in the VD and eCD groups (each 0 of 25; 0%, 95% confidence interval [CI], 0-13.7). Pulmonary interstitial syndrome was found in 2 of 25 (8%, 95% CI, 1-26) women undergoing an uCD (P = .490 for VD versus uCD and P = .490 for eCD versus uCD). In 1 woman, this correlated clinically with the development of pulmonary edema. One or more positive lung regions were present in 5 of 25 (20%), 6 of 25 (24%), and 11 of 25 (44%) parturients following VD, eCD, and uCD, respectively (P = .136). Positive lung regions were predominantly found in lateral lung regions. The number of positive lung regions showed a weak correlation with patient age (r = 0.25, 95% CI, 0.05-0.47; P = .033). No significant association was found between LUS pattern and parity, duration of labor, labor augmentation, labor induction, estimated total intravenous fluid intake, or net intravenous fluid intake.Although many focal areas of increased extravascular lung water (20%-44% prevalence) can be identified on LUS, the overall prevalence of pulmonary interstitial syndrome was 2.7% (2 of 75; 95% CI, 0.3-9.3) among healthy term parturients soon after delivery. Focal areas of positive lung water regions were weakly correlated with maternal age.

    View details for DOI 10.1213/ANE.0000000000005464

    View details for PubMedID 33721873

  • A systematic review of patient-reported outcome measures used to assess sleep in postpartum women using Consensus Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines. Sleep Sultan, P. n., Ando, K. n., Sultan, E. n., Hawkins, J. n., Blake, L. n., Barwick, F. n., Kawai, M. n., Carvalho, B. n. 2021

    Abstract

    We performed a systematic review to identify the best patient-reported outcome measure (PROM) of postpartum sleep in women.We searched 4 databases for validated PROMs used to assess postpartum sleep. Studies were considered if they evaluated at least 1 psychometric measurement property of a PROM. An overall rating was assigned for each psychometric measurement property of each PROM based upon COSMIN criteria. A modified GRADE approach was used to assess the level of evidence and recommendations were then made for each PROM.We identified 15 validation studies of 8 PROMs, in 9,070 postpartum women. An adequate number of sleep domains was assessed by 5 PROMs: Bergen Insomnia Scale (BIS), Pittsburgh Sleep Quality Index (PSQI), General Sleep Disturbance Scale (GSDS), Athens Insomnia Scale (AIS) and the Sleep Symptom Checklist (SSC). BIS and GSDS were the only PROMs to demonstrate adequate content validity and at least a low level of evidence of sufficient internal consistency, resulting in Class A recommendations. The BIS was the only PROM, which is easily accessible and free to use for non-commercial research, that achieved a Class A recommendation.The BIS is the best currently available PROM of postpartum sleep. However, this PROM fails to assess several important domains such as sleep duration (and efficiency), chronotype, sleep-disordered breathing and medication usage. Future studies should focus on evaluating the psychometric measurement properties of BIS in the North American setting and in different cultural groups, or to develop a more specific PROM of postpartum sleep.

    View details for DOI 10.1093/sleep/zsab128

    View details for PubMedID 34013345

  • Use of Patient-Reported Outcome Measures to Assess Outpatient Postpartum Recovery: A Systematic Review. JAMA network open Sultan, P., Sharawi, N., Blake, L., Ando, K., Sultan, E., Aghaeepour, N., Carvalho, B., Sadana, N. 2021; 4 (5): e2111600

    Abstract

    Outpatient postpartum recovery is an underexplored area of obstetrics. There is currently no consensus regarding which patient-reported outcome measure (PROM) clinicians and researchers should use to evaluate postpartum recovery.To evaluate PROMs of outpatient postpartum recovery using Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines.An initial literature search performed in July 2019 identified postpartum recovery PROMs and validation studies. A secondary search in July 2020 identified additional validation studies. Both searches were performed using 4 databases (Web of Science, Embase, PubMed, and CINAHL), with no date limiters. Studies with PROMs evaluating more than 3 proposed outpatient postpartum recovery domains were considered. Studies were included if they assessed any psychometric measurement property of the included PROMs in the outpatient postpartum setting. The PROMs were assessed for the following 8 psychometric measurement properties, as defined by COSMIN: content validity, structural validity, internal consistency, cross-cultural validity and measurement invariance, reliability, measurement error, hypothesis testing, and responsiveness. Psychometric measurement properties were evaluated in each included study using the COSMIN criteria by assessing (1) the quality of the methods (very good, adequate, doubtful, inadequate, or not assessed); (2) overall rating of results (sufficient, insufficient, inconsistent, or indeterminate); (3) level of evidence assessed using the Grading of Recommendations, Assessment, Development and Evaluations assessment tool; and (4) level of recommendation, which included class A (recommended for use; showed adequate content validity with at least low-quality evidence for sufficient internal consistency), class B (not class A or class C), or class C (not recommended).In total, 15 PROMs (7 obstetric specific and 8 non-obstetric specific) were identified, evaluating outpatient postpartum recovery in 46 studies involving 19 165 women. The majority of psychometric measurement properties of the included PROMs were graded as having very-low-level or low-level evidence. The best-performing PROMs that received class A recommendations were the Maternal Concerns Questionnaire, the Postpartum Quality of Life tool, and the World Health Organization Quality of Life-BREF. The remainder of the evaluated PROMs had insufficient evidence to make recommendations regarding their use (and received class B recommendations).This review found that the best-performing PROMs currently available to evaluate outpatient postpartum recovery were the Maternal Concerns Questionnaire, the Postpartum Quality of Life tool, and the World Health Organization Quality of Life-BREF; however, these tools all had significant limitations. This study highlights the need to focus future efforts on robustly developing and validating a new PROM that may comprehensively evaluate outpatient postpartum recovery.

    View details for DOI 10.1001/jamanetworkopen.2021.11600

    View details for PubMedID 34042993

  • A systematic review of patient-reported outcome measures used to assess postpartum pain using Consensus Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines. British journal of anaesthesia Sultan, P. n., Ando, K. n., Sultan, E. n., Hawkins, J. E., Chitneni, A. n., Sharawi, N. n., Sadana, N. n., Blake, L. E., Singh, P. M., Flood, P. n., Carvalho, B. n. 2021

    Abstract

    We performed a systematic review using Consensus Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines to identify the best available patient-reported outcome measure (PROM) of postpartum pain.This review follows COSMIN guidelines. We searched four databases with no date limiters, for previously identified validated PROMs used to assess postpartum pain. PROMs evaluating more than one author-defined domain of postpartum pain were assessed. We sought studies evaluating psychometric properties. An overall rating was then assigned based upon COSMIN analysis, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the level of evidence for psychometric properties of included PROMs. These assessments were used to make recommendations and identify the best PROM to assess postpartum pain.We identified 19 studies using seven PROMs (involving 3511 women), which evaluated postpartum pain. All included studies evaluated ≥1 psychometric property of the included PROMs. An adequate number of pain domains was assessed by the Brief Pain Inventory (BPI), Short Form-BPI (SF-BPI), and McGill Pain Questionnaire (MPQ). The SF-BPI was the only PROM to demonstrate adequate content validity and at least a low-level of evidence for sufficient internal consistency, resulting in a Class A recommendation (the best performing instrument, recommended for use).SF-BPI is the best currently available PROM to assess postpartum pain. However, it fails to assess several important domains and only just met the criteria for a Class A recommendation. Future studies are warranted to develop, evaluate, and implement a new PROM designed to specifically assess postpartum pain.

    View details for DOI 10.1016/j.bja.2021.03.035

    View details for PubMedID 34016441

  • Acute Pain Burden and Opioid Dose Requirements after Cesarean Delivery in Parturients with Preexisting Chronic Back Pain and Migraine. Anesthesiology research and practice Komatsu, R., Nash, M. G., Ruth, K. C., Harbour, W., Ziga, T. M., Mandalia, S., Dinges, E. M., Singh, D., El-Omrani, H., Reno, J., Carvalho, B., Bollag, L. A. 2021; 2021: 3305579

    Abstract

    Introduction: Preexisting chronic pain has been reported to be a consistent risk factor for severe acute postoperative pain. However, each specific chronic pain condition has unique pathophysiology, and it is possible that the effect of each condition on postoperative pain is different.Methods: This is a retrospective cohort study of pregnant women with preexisting chronic pain conditions (i.e., migraine, chronic back pain, and the combination of migraine+chronic back pain), who underwent cesarean delivery. The effects of the three chronic pain conditions on time-weighted average (TWA) pain score (primary outcome) and opioid dose requirements in morphine milligram equivalents (MME) during postoperative 48 hours were compared.Results: The TWA pain score was similar in preexisting migraine and chronic back pain. Chronic back pain was associated with significantly greater opioid dose requirements than migraine (12.92MME, 95% CI: 0.41 to 25.43, P=0.041). Preoperative opioid use (P < 0.001) was associated with a greater TWA pain score. Preoperative opioid use (P < 0.001), smoking (P=0.004), and lower postoperative ibuprofen dose (P=0.002) were associated with greater opioid dose requirements.Conclusions: Findings suggest women with chronic back pain and migraine do not report different postpartum pain intensities; however, women with preexisting chronic back pain required 13MME greater opioid dose than those with migraine during 48 hours after cesarean delivery.

    View details for DOI 10.1155/2021/3305579

    View details for PubMedID 34504525

  • A Peripheral Immune Signature of Labor Induction. Frontiers in immunology Ando, K., Hédou, J. J., Feyaerts, D., Han, X., Ganio, E. A., Tsai, E. S., Peterson, L. S., Verdonk, F., Tsai, A. S., Marić, I., Wong, R. J., Angst, M. S., Aghaeepour, N., Stevenson, D. K., Blumenfeld, Y. J., Sultan, P., Carvalho, B., Stelzer, I. A., Gaudillière, B. 2021; 12: 725989

    Abstract

    Approximately 1 in 4 pregnant women in the United States undergo labor induction. The onset and establishment of labor, particularly induced labor, is a complex and dynamic process influenced by multiple endocrine, inflammatory, and mechanical factors as well as obstetric and pharmacological interventions. The duration from labor induction to the onset of active labor remains unpredictable. Moreover, prolonged labor is associated with severe complications for the mother and her offspring, most importantly chorioamnionitis, uterine atony, and postpartum hemorrhage. While maternal immune system adaptations that are critical for the maintenance of a healthy pregnancy have been previously characterized, the role of the immune system during the establishment of labor is poorly understood. Understanding maternal immune adaptations during labor initiation can have important ramifications for predicting successful labor induction and labor complications in both induced and spontaneous types of labor. The aim of this study was to characterize labor-associated maternal immune system dynamics from labor induction to the start of active labor. Serial blood samples from fifteen participants were collected immediately prior to labor induction (baseline) and during the latent phase until the start of active labor. Using high-dimensional mass cytometry, a total of 1,059 single-cell immune features were extracted from each sample. A multivariate machine-learning method was employed to characterize the dynamic changes of the maternal immune system after labor induction until the establishment of active labor. A cross-validated linear sparse regression model (least absolute shrinkage and selection operator, LASSO) predicted the minutes since induction of labor with high accuracy (R = 0.86, p = 6.7e-15, RMSE = 277 min). Immune features most informative for the model included STAT5 signaling in central memory CD8+ T cells and pro-inflammatory STAT3 signaling responses across multiple adaptive and innate immune cell subsets. Our study reports a peripheral immune signature of labor induction, and provides important insights into biological mechanisms that may ultimately predict labor induction success as well as complications, thereby facilitating clinical decision-making to improve maternal and fetal well-being.

    View details for DOI 10.3389/fimmu.2021.725989

    View details for PubMedID 34566984

    View details for PubMedCentralID PMC8458888

  • The Generalizability of Patients' Preferences and Concerns regarding Anesthesia Care for Cesarean Delivery: A Prospective Survey. Anesthesiology research and practice Smith, A. J., Daly, J., Arnolds, D. E., Scavone, B. M., Carvalho, B. 1800; 2021: 9002061

    Abstract

    Background: False assumptions regarding the generalizability of patients' expectations and preferences across different demographic groups may contribute in part to the increased prevalence of negative peripartum outcomes seen among women of color. The intention of this study was to determine preferences and concerns regarding anesthesia care during cesarean delivery in a largely African-American population and to compare them to those obtained in a prior study conducted in a demographically distinct population.Methods: Women presenting for scheduled cesarean delivery or induction of labor completed a preoperative survey requesting demographic information and the opportunity to rank ten common potential anesthetic outcomes in relation to each other from most to least desirable. Participants were also asked about their biggest fear concerning their anesthetic and their preferences and expectations regarding degree of wakefulness, pain, and other adverse events. Those who underwent cesarean delivery were administered a briefer postoperative survey. We tabulated preference rankings and then compared demographic and outcome data to that obtained in a previous study with a demographically dissimilar population.Results: A total of 73 women completed the preoperative survey, and 64 took the postoperative survey. Pain during and after cesarean delivery was ranked as least desirable outcomes and fear of paralysis was respondents' principal concern with neuraxial anesthesia. Postoperative concerns were similar to preoperative concerns and did not correlate with the frequency with which specific adverse outcomes occurred. These results were consistent with those from the previous study despite the women in this study being more likely to be younger, unmarried, African-American, and less educated than those in the previous investigation.Conclusions: Patient preference rankings and concerns were remarkably similar to those previously demonstrated despite a number of demographic differences between the two populations, suggesting generalizability of these preferences to a broader obstetric population.

    View details for DOI 10.1155/2021/9002061

    View details for PubMedID 34899902

  • Ampicillin Pharmacokinetics in Peripartum and Laboring Women. American journal of perinatology Judy, A. E., Frymoyer, A., Ansari, J., Drover, D. R., Carvalho, B. 2021

    Abstract

    Ampicillin is used for multiple peripartum indications including prevention of neonatal group beta streptococcus (GBS) and treatment of chorioamnionitis. Despite its widespread use in obstetrics, existing pharmacokinetic data for ampicillin do not address contemporary indications or dosing paradigms for this population. We sought to characterize the pharmacokinetic profile of ampicillin administered to laboring women.Using whole blood dried blood spot sampling technique, maternal blood samples were collected at specified times from 31 women receiving IV ampicillin for peripartum indications. Women received either a 2-g loading dose with 1-g administered every 4 h (GBS), or 2-g every 6 h (chorioamnionitis). Pharmacokinetics were analyzed via a population approach with non-linear mixed-effect modeling.The data were best described by a two-compartment model with first-order elimination, with the following whole blood parameters: central volume of distribution (V1) 75.2 L (95% CI 56.3-93.6), clearance (CL) 82.4 L/h (95% CI 59.7-95.7), inter-compartmental clearance (Q) 20.9 L/h (95% CI 16.2-38.2), and peripheral volume of distribution (V2) 61.1 L (95% CI 26.1-310.5). Inter-patient variation in CL and V1 was large (42.0% and 56.7% respectively). Simulations of standard dosing strategies demonstrated over 98% of women are predicted to achieve an estimated free plasma concentration above MIC 0.5 mcg/mL for more than 50% of the dosing interval.Although large variation in the pharmacokinetics of ampicillin in pregnant women exists, as predicted by our model, current standard dosing strategies achieve adequate exposure for GBS in nearly all patients.

    View details for DOI 10.1055/a-1674-6394

    View details for PubMedID 34670320

  • Proposed domains for assessing postpartum recovery: A concept elicitation study. BJOG : an international journal of obstetrics and gynaecology Sultan, P., Jensen, S. E., Taylor, J., El-Sayed, Y., Carmichael, S., Cella, D., Angst, M. S., Gaudilliere, B., Lyell, D. J., Carvalho, B. 2021

    Abstract

    To propose postpartum recovery domains.Concept elicitation study SETTING: Semi-structured interviews POPULATION: 10 writing committee members and 50 stakeholder interviews (23 postpartum women, 9 general obstetricians, 5 maternal fetal medicine specialists, 8 nurses and 5 obstetric anaesthetists).Alternating interviews and focus group meetings until concept saturation was achieved (no new themes in 3 consecutive interviews). Interviews were digitally recorded and transcribed, and an iterative coding process utilised to identify domains.The primary outcome was to identify recovery domains. We also report key symptoms and concerns. Discussion frequency and importance scores (0-100; 0=not important; 100=vitally important to recovery) were used to rank domains. Discussion frequency was used to rank factors helping and hindering recovery, and determine the greatest challenges experienced postpartum.34 interviews and 2 focus group meetings were performed. The 13 postpartum recovery domains identified, (ranked highest to lowest) were: psychosocial distress, surgical / medical factors, infant feeding and breast health, psychosocial support, pain, physical function, sleep, motherhood experience, infant health, fatigue, appearance, sexual function and cognition. The most frequently discussed factors facilitating postpartum recovery were: family support, lactation / breastfeeding support and partner support. The most frequently discussed factor hindering recovery was inadequate social support. The most frequent challenges reported were: breastfeeding (week 1), breastfeeding (week 3) and sleep (week 6).We propose 13 domains, which comprehensively describe recovery in women delivering in a single centre within the United States. This provides a novel framework to study the postpartum recovery process.

    View details for DOI 10.1111/1471-0528.16937

    View details for PubMedID 34536324

  • Pain after vaginal delivery and during breastfeeding: underexplored and underappreciated. International journal of obstetric anesthesia Sultan, P. n., Carvalho, B. n. 2021; 46: 102969

    View details for DOI 10.1016/j.ijoa.2021.102969

    View details for PubMedID 33794439

  • Spinal prilocaine for caesarean section: walking a fine line. Anaesthesia Carvalho, B. n., Sultan, P. n. 2021

    View details for DOI 10.1111/anae.15341

    View details for PubMedID 33428235

  • Regional anaesthesia for labour, operative vaginal delivery and caesarean delivery: a narrative review. Anaesthesia Sultan, P. n., Sultan, E. n., Carvalho, B. n. 2021; 76 Suppl 1: 136–47

    Abstract

    This narrative review discusses recent evidence surrounding the use of regional anaesthesia in the obstetric setting, including intrapartum techniques for labour and operative vaginal delivery, and caesarean delivery. Pudendal nerve blockade, ideally administered by an obstetrician, should be considered for operative vaginal delivery if neuraxial analgesia is contraindicated. Regional techniques are increasingly utilised in clinical practice for caesarean delivery to minimise opioid consumption, reduce pain, improve postpartum recovery and facilitate earlier discharge as part of enhanced recovery protocols. The evidence surrounding transversus abdominis plane and quadratus lumborum blockade supports their use when: long-acting neuraxial opioids cannot be administered due to contraindications; if emergency delivery necessitates general anaesthesia; or as a postoperative rescue technique. Current data suggest quadratus lumborum blockade is no more effective than transversus abdominis plane blockade after caesarean delivery. Transversus abdominis plane blockade, wound catheter insertion and single shot wound infiltration are all effective techniques for reducing postoperative opioid consumption, with transversus abdominis plane blockade favoured, followed by wound catheters and then wound infiltration. Ilio-inguinal and iliohypogastric, erector spinae plane and rectus sheath blockade all require further studies to determine their efficacy for caesarean delivery in the presence or absence of long-acting neuraxial opioids. Future studies are needed to: compare approaches for individual techniques; determine which combinations of techniques and dosing regimens result in optimal analgesic and recovery outcomes following delivery; and elucidate the populations that benefit most from regional anaesthesia in the obstetric setting.

    View details for DOI 10.1111/anae.15233

    View details for PubMedID 33426655

  • Comment on the editorial relating to: Transversus abdominis plane block compared with wound infiltration for postoperative analgesia following Cesarean delivery: a systematic review and network meta-analysis. Canadian journal of anaesthesia = Journal canadien d'anesthesie Sultan, P. n., Carvalho, B. n., Halpern, S. n. 2021

    View details for DOI 10.1007/s12630-020-01872-5

    View details for PubMedID 33403553

  • Antibiotic Prophylaxis for Cesarean Delivery: A Survey of Anesthesiologists ANESTHESIOLOGY RESEARCH AND PRACTICE Reiff, E. S., Habib, A. S., Carvalho, B., Raghunathan, K. 2020; 2020
  • Antibiotic Prophylaxis for Cesarean Delivery: A Survey of Anesthesiologists. Anesthesiology research and practice Reiff, E. S., Habib, A. S., Carvalho, B., Raghunathan, K. 2020; 2020: 3741608

    Abstract

    The most common complication after cesarean delivery is surgical site infection. Antibiotic prophylaxis reduces infectious morbidity and current anesthetic quality metrics include preincision antibiotic prophylaxis. Recently, studies suggest reductions in infectious morbidity with the addition of azithromycin for unscheduled cesarean delivery. Larger doses of cefazolin are recommended for morbidly obese women, but evidence is conflicting. The aim of this study was to survey anesthesiologists to assess current practice for antibiotic prophylaxis for cesarean delivery.We invited a random sample of 10,000 current members of the American Society of Anesthesiologists to complete an online survey about their current practice of antibiotic prophylaxis for cesarean delivery in November 2017. The survey included questions similar to a previous survey on this topic in 2012.The response rate was 12.2% (n = 1223). Most respondents had at least 15 years of experience (684, 55.9%), work at a nonteaching or community hospital (729, 59.6%), with >500 cesarean deliveries annually (619, 50.6%), and administer obstetric anesthesia several times a week (690, 56.4%). Routine preincision antibiotic prophylaxis was reported by 1162 (95.0%) of the 1223 respondents, a substantial improvement versus the 63.5% reported in the previous study in 2012. For intrapartum cesarean deliveries, 141 (11.5%) administer azithromycin for unscheduled cesarean deliveries. Those who use cefazolin, 509 (42.5%) administer 3 g for morbidly obese women.Adherence to preincision antibiotic prophylaxis for cesarean delivery is very high, a significant improvement within 5 years. A minority of anesthesiologists utilize azithromycin for intrapartum cesarean deliveries. The dose of cefazolin for morbidly obese women varies widely.

    View details for DOI 10.1155/2020/3741608

    View details for PubMedID 33488702

    View details for PubMedCentralID PMC7787788

  • Confounders Not General Anesthesia Likely Explain Greater Postpartum Depression. Anesthesia and analgesia Ansari, J., Carvalho, B., Weiniger, C. F., Riley, E. T. 2020; 131 (6): e248–e250

    View details for DOI 10.1213/ANE.0000000000004850

    View details for PubMedID 33196470

  • Alternate Dosing Protocol for Magnesium Sulfate in Obese Women With Preeclampsia: A Randomized Controlled Trial. Obstetrics and gynecology Brookfield, K. F., Tuel, K., Rincon, M., Vinson, A., Caughey, A. B., Carvalho, B. 2020

    Abstract

    OBJECTIVE: To evaluate whether obese women need greater doses of magnesium sulfate to obtain therapeutic serum concentrations for eclamptic seizure prevention.METHODS: Women with preeclampsia and a body mass index (BMI) of 35 or higher were randomly allocated to either the Zuspan regimen of magnesium sulfate (4-g intravenous [IV] loading dose, then a 1-g/h infusion) or to alternate dosing (6-g IV loading dose, then a 2-g/h infusion). Women had serum magnesium concentrations obtained at baseline, as well as after administration of magnesium sulfate at 1 hour, 4 hours, and delivery. The primary outcome was the proportion of women who had subtherapeutic serum magnesium concentrations (less than 4.8 mg/dL) 4 hours after administration. A sample size of 18 women per group was planned to compare the proportion of women with subtherapeutic serum magnesium concentrations in each group.RESULTS: From July 12, 2016, to March 14, 2019, 89 women with preeclampsia were screened and 37 were enrolled: 18 to the Zuspan regimen and 19 to the alternate regimen. A significantly greater proportion of women administered the Zuspan regimen had subtherapeutic serum magnesium concentrations at 4 hours (100% [95% CI 59-100] vs 63% [95% CI 41-81]; P=.01) compared with women administered the alternate higher dose regimen. At 4 hours, mean concentrations were significantly higher in the alternate regimen group (3.53 mg/dL±0.3 [Zuspan regimen] vs 4.41±0.5 [alternate regimen]; P<.01).CONCLUSION: The alternate dosing regimen of a 6-g IV loading dose followed by a 2-g/h IV maintenance dose more reliably achieves therapeutic serum magnesium concentrations (as defined by a concentration of at least 4.8 mg/dL) in obese women with preeclampsia.CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02835339.

    View details for DOI 10.1097/AOG.0000000000004137

    View details for PubMedID 33156201

  • Correction to: Transversus abdominis plane block compared with wound infiltration for postoperative analgesia following Cesarean delivery: a systematic review and network meta-analysis. Canadian journal of anaesthesia = Journal canadien d'anesthesie Sultan, P., Patel, S. D., Jadin, S., Carvalho, B., Halpern, S. H. 2020

    Abstract

    The original article was updated to amend number "0.09" in Table2a (instead "-0.09").

    View details for DOI 10.1007/s12630-020-01839-6

    View details for PubMedID 33089415

  • Transversus Abdominis Plane Block With Liposomal Bupivacaine for Pain After Cesarean Delivery in a Multicenter, Randomized, Double-Blind, Controlled Trial. Anesthesia and analgesia Nedeljkovic, S. S., Kett, A., Vallejo, M. C., Horn, J., Carvalho, B., Bao, X., Cole, N. M., Renfro, L., Gadsden, J. C., Song, J., Yang, J., Habib, A. S. 2020

    Abstract

    BACKGROUND: In women undergoing cesarean delivery under spinal anesthesia with intrathecal morphine, transversus abdominis plane (TAP) block with bupivacaine hydrochloride (HCl) may not improve postsurgical analgesia. This lack of benefit could be related to the short duration of action of bupivacaine HCl. A retrospective study reported that TAP block with long-acting liposomal bupivacaine (LB) reduced opioid consumption and improved analgesia following cesarean delivery. Therefore, we performed a prospective multicenter, randomized, double-blind trial examining efficacy and safety of TAP block with LB plus bupivacaine HCl versus bupivacaine HCl alone.METHODS: Women (n = 186) with term pregnancies undergoing elective cesarean delivery under spinal anesthesia were randomized (1:1) to TAP block with LB 266 mg plus bupivacaine HCl 50 mg or bupivacaine HCl 50 mg alone. Efficacy was evaluated in a protocol-compliant analysis (PCA) set that was defined a priori. The primary end point was total postsurgical opioid consumption (oral morphine equivalent dosing [MED]) through 72 hours. Pain intensity was measured using a visual analog scale. Adverse events (AEs) after treatment were recorded through day 14.RESULTS: Total opioid consumption through 72 hours was reduced with LB plus bupivacaine HCl versus bupivacaine HCl alone (least squares mean [LSM] [standard error (SE)] MED, 15.5 mg [6.67 mg] vs 32.0 mg [6.25 mg]). This corresponded to an LSM treatment difference of -16.5 mg (95% confidence interval [CI], -30.8 to -2.2 mg; P = .012). The area under the curve of imputed pain intensity scores through 72 hours supported noninferiority of LB plus bupivacaine HCl versus bupivacaine HCl alone (LSM [SE], 147.9 [21.13] vs 178.5 [19.78]; LSM treatment difference, -30.6; 95% CI, -75.9 to 14.7), with a prespecified noninferiority margin of 36 (P = .002). In an analysis of all treated patients, including those not meeting criteria for inclusion in the PCA, there was no difference in postsurgical opioid consumption between groups. In the LB plus bupivacaine HCl group, 63.6% of patients experienced an AE after treatment versus 56.2% in the bupivacaine HCl-alone group. Serious AEs after treatment were rare (3% in both groups).CONCLUSIONS: TAP block using LB plus bupivacaine HCl as part of a multimodal analgesia protocol incorporating intrathecal morphine resulted in reduced opioid consumption after cesarean delivery in the PCA set. Results suggest that with correct TAP block placement and adherence to a multimodal postsurgical analgesic regimen, there is an opioid-reducing benefit of adding LB to bupivacaine TAP blocks after cesarean delivery (ClinicalTrials.gov identifier: NCT03176459).

    View details for DOI 10.1213/ANE.0000000000005075

    View details for PubMedID 32739962

  • Reply to: Re: enhanced recovery for cesarean section: beyond pain control. International journal of obstetric anesthesia Kleiman, A. M., Chisholm, C. A., Carvalho, B., Tiouririne, M. 2020; 44: 52

    View details for DOI 10.1016/j.ijoa.2020.07.004

    View details for PubMedID 32799065

  • Re: Association between opioid use after intrapartum cesarean delivery and repeat cesarean delivery: a retrospective cohort study. International journal of obstetric anesthesia Komatsu, R., Carvalho, B., Flood, P. D. 2020; 43: 30

    View details for DOI 10.1016/j.ijoa.2020.05.009

    View details for PubMedID 32570048

  • Impact of enhanced recovery after cesarean delivery on maternal outcomes: A meta-analysis Taylor, J., Sultan, P., Sharawi, N., Habib, A. S., Carvalho, B., Blake, L. LIPPINCOTT WILLIAMS & WILKINS. 2020: 541
  • Enhanced recovery after surgery for cesarean delivery. Current opinion in obstetrics & gynecology Suharwardy, S., Carvalho, B. 2020

    Abstract

    PURPOSE OF REVIEW: The aim of this article is to describe enhanced recovery after surgery (ERAS) and its application to cesarean delivery.RECENT FINDINGS: ERAS is a standardized, multidisciplinary approach to improving the care of surgical patients, from the preoperative planning through the surgery and postoperative period. ERAS is associated with many benefits, including improved patient outcomes and satisfaction as well as reduced length-of-stay and cost. Obstetric implementation of ERAS protocols has lagged compared to other surgical subspecialties. Given the volume of cesarean deliveries worldwide, improving the quality and cost of care through broad application of ERAS could have significant benefits.SUMMARY: ERAS pathways specific to cesarean delivery should be implemented and can improve the quality of care provided.

    View details for DOI 10.1097/GCO.0000000000000616

    View details for PubMedID 32068543

  • Conversion of labour epidural analgesia to surgical anaesthesia for emergency intrapartum Caesarean section BJA EDUCATION Desai, N., Carvalho, B. 2020; 20 (1): 26–31
  • Conversion of labour epidural analgesia to surgical anaesthesia for emergency intrapartum Caesarean section. BJA education Desai, N., Carvalho, B. 2020; 20 (1): 26-31

    View details for DOI 10.1016/j.bjae.2019.09.006

    View details for PubMedID 33456912

    View details for PubMedCentralID PMC7807843

  • Evaluation of Domains of Patient-Reported Outcome Measures for Recovery After Childbirth: A Scoping and Systematic Review. JAMA network open Sultan, P. n., Sadana, N. n., Sharawi, N. n., Blake, L. n., El-Boghdadly, K. n., Falvo, A. n., Ciechanowicz, S. n., Athar, W. n., Shah, R. n., Guo, N. n., Jensen, S. n., El-Sayed, Y. n., Cella, D. n., Carvalho, B. n. 2020; 3 (5): e205540

    Abstract

    Despite the global delivery rate being approximately 259 deliveries per minute in 2018, postpartum recovery remains poorly defined.To identify validated patient-reported outcome measures (PROMs) used to assess outpatient and inpatient postpartum recovery, evaluate frequency of PROM use, report the proportion of identified PROMs used within each recovery domain, report the number of published studies within each recovery domain, summarize descriptive data (country of origin, year of study, and journal specialty) for published studies using PROMs to evaluate postpartum recovery, and report PROMs used to evaluate global postpartum recovery.This study followed PRISMA-ScR guidelines. A literature search of 4 databases (MEDLINE through PubMed, Embase, Web of Science, and CINAHL) was performed on July 1, 2019, to identify PROMs used to evaluate 12 author-defined domains of postpartum recovery. All psychometrically evaluated PROMs used to evaluate inpatient or outpatient postpartum recovery after all delivery modes were included.From 8008 screened titles and abstracts, 573 studies (515 outpatient and 58 inpatient) were identified in this review. A total of 201 PROMs were used to assess recovery for outpatient studies and 73 PROMs were used to assess recovery for inpatient studies. The top 5 domains (with highest to lowest numbers of PROMs) used to assess outpatient recovery were psychosocial distress (77 PROMs), surgical complications (26 PROMs), psychosocial support (27 PROMs), motherhood experience (16 PROMs), and sexual function (13 PROMs). Among inpatient studies, the top 5 domains were psychosocial distress (32 PROMs), motherhood experience (7 PROMs), psychosocial support (5 PROMs), fatigue (5 PROMs), and cognition (3 PROMs). The 3 most frequently used PROMs were the Edinburgh Postnatal Depression Scale (267 studies), Short-Form 36 Health Questionnaire (global recovery assessment; 40 studies), and Female Sexual Function Index (35 studies). A total of 24 global recovery PROMs were identified among all included studies. Most studies were undertaken in the United States within the last decade and were published in psychiatry and obstetrics and gynecology journals.Most PROMs identified in this review evaluated a single domain of recovery. Future research should focus on determining the psychometric properties of individual and global recovery PROMs identified in this review to provide recommendations regarding optimum measures of postpartum recovery.

    View details for DOI 10.1001/jamanetworkopen.2020.5540

    View details for PubMedID 32442292

  • Pain management during labor and vaginal birth. Best practice & research. Clinical obstetrics & gynaecology Nanji, J. A., Carvalho, B. n. 2020

    Abstract

    Neuraxial analgesia provides excellent pain relief in labor. Optimizing initiation and maintenance of neuraxial labor analgesia requires different strategies. Combined spinal-epidurals or dural puncture epidurals may offer advantages over traditional epidurals. Ultrasound is useful in certain patients. Maintenance of analgesia is best achieved with a background regimen (either programmed intermittent boluses or a continuous epidural infusion) supplemented with patient-controlled epidural analgesia and using dilute local anesthetics combined with opioids such as fentanyl. Nitrous oxide and systemic opioids are also used for pain relief. Nitrous oxide may improve satisfaction despite variable effects on pain. Systemic opioids can be administered by healthcare providers or using patient-controlled analgesia. Appropriate choice of drug should take into account the stage and progression of labor, local safety protocols, and maternal and fetal/neonatal side effects. Pain in labor is complex, and women should fully participate in the decision-making process before any one modality is selected.

    View details for DOI 10.1016/j.bpobgyn.2020.03.002

    View details for PubMedID 32265134

  • Hemodynamic profiles with and without left uterine displacement: A randomized study in term pregnancies receiving subarachnoid blockade for cesarean delivery. Journal of clinical anesthesia Chungsamarnyart, Y. n., Wacharasint, P. n., Carvalho, B. n. 2020; 64: 109796

    Abstract

    The aim of this study was to evaluate the effect of left uterine displacement (LUD) on maternal hemodynamic measures following subarachnoid blockade (SAB) for cesarean delivery (CD). The primary outcome was cardiac output (CO) differences between the LUD and non-LUD groups pre-delivery.Prospective, randomized, controlled study.Obstetric operating room.We studied hemodynamic profiles in sixty healthy women with term pregnancies who underwent elective CD with SAB. Hemodynamics were measured using a non-invasive CO monitor, the Nexfin™. All women received a crystalloid 10 mL/kg preload, and hypotension was treated with ephedrine boluses.Sixty women with term pregnancies were randomized into two groups: LUD group (received 15-30° LUD after SAB, n = 30) and non-LUD group (no LUD after SAB, n = 30).Patient's hemodynamic variables including systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), CO, systemic vascular resistance (SVR), and left ventricular contractility index (dP/dT) were measured continuously from pre-SAB until end of surgery.In pre-delivery phase at 5 min after spinal anesthesia, the LUD group had significantly higher CO (7.20 ± 1.78 [95%CI 6.53-7.87] vs. 6.23 ± 1.44 L/min [95% CI 5.69-6.77]; p = 0.016) and higher dP/dT (784 ± 313 vs. 604 ± 241 mmHg/s; p = 0.020) than the non-LUD group. The LUD group had a lower incidence of maternal systolic hypotension at 5-min post-SAB (16.7% vs. 53.3% in non-LUD group, p = 0.003).The study demonstrates modest hemodynamic advantages (higher CO, less hypotension, higher dP/dT) with pre-delivery LUD. The results support maternal hemodynamic benefits of LUD until delivery in women with term pregnancies undergoing CD with SAB.

    View details for DOI 10.1016/j.jclinane.2020.109796

    View details for PubMedID 32305794

  • Enhanced recovery after caesarean delivery versus standard care studies: a systematic review of interventions and outcomes. International journal of obstetric anesthesia Sultan, P. n., Sharawi, N. n., Blake, L. n., Carvalho, B. n. 2020

    Abstract

    This systematic review aimed to determine whether enhanced recovery after caesarean delivery (ERAC) protocols should be adopted.We searched four databases and abstracts from meetings for studies comparing ERAC to standard care. We report interventions, outcomes, qualitative impact of ERAC implementation and use GRADE scoring to determine quality of evidence and make recommendations regarding ERAC adoption, based on key outcomes (length of stay, financial savings, satisfaction, re-admission, opioid usage, breastfeeding success and maternal-neonatal bonding).Eleven published studies and 36 abstracts evaluating ERAC were included. Forty-two study interventions (40 in published studies) and 90 outcome measures (60 in published studies) were used. Most studies showed a reduction in hospital stay (6/7 studies) and reduced costs (2/2 studies) with ERAC compared with standard care. Satisfaction was inconsistently reported. Re-admission rates were similar between groups. Two studies showed a reduction and two showed no difference in opioid consumption with ERAC. One study showed improvement and another showed no change in outpatient breastfeeding rates with ERAC. One study showed better inpatient maternal-neonatal bonding. The GRADE level of evidence was low or very low for all outcomes.Studies evaluating ERAC used heterogeneous interventions and outcomes. Although there is currently low- or very low-level evidence supporting all outcomes evaluated, the majority of studies showed some benefits and none reported harm. On balance, we recommend the use of ERAC. Future studies are needed to strengthen ERAC recommendations by standardising interventions and reported outcomes.

    View details for DOI 10.1016/j.ijoa.2020.03.003

    View details for PubMedID 32299662

  • Alternate dosing for magnesium in obese preeclamptic women: a cost-effectiveness analysis Hersh, A. R., Harmon, D., Chaiken, S., Brookfield, K., Vinson, A., Carvalho, B., Caughey, A. B. MOSBY-ELSEVIER. 2020: S365
  • Do alternative magnesium sulfate protocols in obese preeclamptic women impact neonatal morbidity? Vinson, A., Rincon, M., Tuel, K., Carvalho, B., Caughey, A. B., Brookfield, K. MOSBY-ELSEVIER. 2020: S500
  • A randomized trial of an alternate dosing protocol of magnesium sulfate in obese preeclamptic women Brookfield, K., Rincon, M., Tuel, K., Vinson, A., Caughey, A. B., Carvalho, B. MOSBY-ELSEVIER. 2020: S19
  • Transversus abdominis plane block compared with wound infiltration for postoperative analgesia following Cesarean delivery: a systematic review and network meta-analysis. Canadian journal of anaesthesia = Journal canadien d'anesthesie Sultan, P. n., Patel, S. D., Jadin, S. n., Carvalho, B. n., Halpern, S. H. 2020

    Abstract

    This systematic review and network meta-analysis (NMA) compared postoperative analgesic efficacy of transversus abdominis plane (TAP) blocks with that of wound infiltration for Cesarean delivery (CD) without long-acting neuraxial opioid administration.We sought randomized-controlled trials comparing TAP vs wound infiltration, and inactive control vs either TAP or wound infiltration. Wound infiltration included single-dose infiltration (WI), or continuous infusion via a catheter (WC). The primary outcome was 24 hr opioid consumption. Secondary outcomes included 12 and 24 hr pain scores (resting and movement), time to first analgesia request, incidence of postoperative nausea and vomiting (PONV), maternal sedation, and pruritus. We performed a NMA incorporating both direct and indirect comparisons and reported standardized mean differences and odds ratios with 95% confidence intervals for continuous and dichotomous outcomes.Forty-two studies were included, comprising 2,906 participants. Transversus abdominis plane blocks and WC were associated with significantly lower 24 hr opioid consumption than inactive controls, but there were no significant differences between WI and inactive controls. There was no statistically significant difference in 24 hr opioid consumption between TAP blocks and WC or WI techniques. The network ranking of treatments was TAP block, followed by WC or WI. No significant differences were shown between TAP, WC, and WI groups for 24 hr pain scores, time to first analgesia, PONV, sedation, and pruritus. Quality of evidence was moderate for most of the outcomes assessed.In the absence of long-acting neuraxial opioid after CD, single-dose TAP blocks and WC are effective opioid-sparing strategies.

    View details for DOI 10.1007/s12630-020-01818-x

    View details for PubMedID 33033957

  • Evaluation of inpatient postpartum recovery using the Obstetric Quality of Recovery-10 patient-reported outcome measure: a single-center observational study. American journal of obstetrics & gynecology MFM Sultan, P. n., Kamath, N. n., Carvalho, B. n., Bansal, P. n., Elkhateb, R. n., Dougan, S. n., Whittington, J. n., Guo, N. n., El-Sayed, Y. n., Mhyre, J. n., Sharawi, N. n. 2020; 2 (4): 100202

    Abstract

    Few adequately validated patient-reported outcome measures are available, which can assess recovery profiles following childbirth.We aimed to determine whether quantitative recovery (using the Obstetric Quality of Recovery-10 patient-reported outcome measure) was superior following vaginal delivery compared with cesarean delivery and evaluate validity, reliability, and responsiveness of this patient-reported outcome measure in the obstetrical setting in the United States.Women recruited into this single-center observational cohort study completed the Obstetric Quality of Recovery-10 and EuroQol 5-dimension 3L patient-reported outcome measures within 72 hours of childbirth. We assessed the validity with hypothesis testing and structural validity. In hypothesis testing, the primary outcome was Obstetric Quality of Recovery-10 scores after vaginal vs cesarean delivery. Secondary outcomes were differences in Obstetric Quality of Recovery-10 scores for vaginal delivery following induction of labor vs spontaneous labor and scheduled vs unplanned cesarean delivery, correlation with clinical parameters (American Society of Anesthesiologists classification grade, body mass index, length of hospital stay, estimated blood loss, transfusion requirement, antiemetic use, and neonatal intensive care unit admission), and qualitative ranking of Obstetric Quality of Recovery-10 items for each delivery mode. Structural validity was assessed by determining the correlation of the Obstetric Quality of Recovery-10 scores with the EuroQol 5-dimension 3L and global health visual analog scale scores. Reliability was assessed using Cronbach alpha and inter-item correlation of Obstetric Quality of Recovery-10 items. Responsiveness was assessed by evaluating the change in Obstetric Quality of Recovery-10 scores over the 72-hour postpartum period.Data from 215 women were analyzed. In hypothesis testing, the median (interquartile range) Obstetric Quality of Recovery-10 scores were higher following vaginal delivery than cesarean delivery (86 [77-94] vs 77 [64-86], respectively; P<.001). Multivariate model demonstrated that Obstetric Quality of Recovery-10 scores were significantly lower after cesarean delivery when adjusting for American Society of Anesthesiologists classification grade, age, body mass index, and ethnicity (R=-8.97; P<.001). Obstetric Quality of Recovery-10 scores were similar between induction of labor and spontaneous labor, and scheduled cesarean delivery and unplanned cesarean delivery. Obstetric Quality of Recovery-10 was correlated with length of hospital stay (R=-0.248; P<.001), estimated blood loss (R=-0.3429; P<.001), transfusion requirement (R=-0.140; P=.041), and antiemetic use (R=-0.280; P<.001). The highest ranked Obstetric Quality of Recovery-10 items were ability to hold baby, feeling in control, and ability to look after personal hygiene. The lowest ranked items were pain and shivering. In structural validity, correlation of Obstetric Quality of Recovery-10 score was moderate with the global health visual analog scale (r=0.511) and EuroQol 5-dimension 3L scores (r=-0.509). In reliability, Cronbach alpha was 0.72 and more than 80% of individual items correlated. In responsiveness, Obstetric Quality of Recovery-10 scores did not change significantly over the study period.Quantitative inpatient recovery following vaginal delivery is superior to cesarean delivery. The Obstetric Quality of Recovery-10 appears to be a valid and reliable patient-reported outcome measure following these delivery modes. Further studies are needed to determine how to improve recovery domains identified in this study, to evaluate Obstetric Quality of Recovery-10 in different languages and determine whether these domains impact outcomes beyond hospitalization.

    View details for DOI 10.1016/j.ajogmf.2020.100202

    View details for PubMedID 33345919

  • Society for Obstetric Anesthesia and Perinatology: Consensus Statement and Recommendations for Enhanced Recovery After Cesarean. Anesthesia and analgesia Bollag, L. n., Lim, G. n., Sultan, P. n., Habib, A. S., Landau, R. n., Zakowski, M. n., Tiouririne, M. n., Bhambhani, S. n., Carvalho, B. n. 2020

    Abstract

    The purpose of this article is to provide a summary of the Enhanced Recovery After Cesarean delivery (ERAC) protocol written by a Society for Obstetric Anesthesia and Perinatology (SOAP) committee and approved by the SOAP Board of Directors in May 2019. The goal of the consensus statement is to provide both practical and where available, evidence-based recommendations regarding ERAC. These recommendations focus on optimizing maternal recovery, maternal-infant bonding, and perioperative outcomes after cesarean delivery. They also incorporate management strategies for this patient cohort, including recommendations from existing guidelines issued by professional organizations such as the American College of Obstetricians and Gynecologists and the American Society of Anesthesiologists. This consensus statement focuses on anesthesia-related and perioperative components of an enhanced recovery pathway for cesarean delivery and provides the level of evidence for each recommendation.

    View details for DOI 10.1213/ANE.0000000000005257

    View details for PubMedID 33177330

  • Comparison of spontaneous versus operative vaginal delivery using Obstetric Quality of Recovery-10 (ObsQoR-10): An observational cohort study. Journal of clinical anesthesia Sultan, P. n., Kormendy, F. n., Nishimura, S. n., Carvalho, B. n., Guo, N. n., Papageorgiou, C. n. 2020; 63: 109781

    Abstract

    We aimed to determine whether patient-reported quality of recovery differed between spontaneous and operative vaginal delivery. We also aimed to psychometrically evaluate the Obstetric Quality of Recovery-10 scoring tool (ObsQoR-10) for use in this setting.Single center observational cohort study.Labour and delivery ward at a peripheral general hospital within the United Kingdom, over a 10-month period.123 women delivering via either spontaneous (n = 68) or operative vaginal delivery (n = 55).Women were asked to complete the ObsQoR-10 and global health visual analogue scale (0-100) on postpartum day 1. A convenience sample of consenting parturients delivering via spontaneous or operative vaginal delivery (forceps or vacuum assisted), were included. In total, 123 deliveries were included (68 via spontaneous and 55 via operative vaginal delivery), with no dropouts.Primary outcome was ObsQoR-10 score and secondary outcomes included measures of validity, reliability and feasibility of ObsQoR-10.Quality of recovery was better following spontaneous vaginal delivery. ObsQoR-10 scores were 80.2 (95% CI 76.4-83.9) and 72.1 (95% CI 67.3-76.9], (a difference in score of 8.1 [95% CI 2.1-14.0]) following spontaneous and operative vaginal delivery respectively (p = 0.008).ObsQoR-10 correlated with global health visual analogue scale score (R = 0.52; p = 0.01) and scores were higher in women requiring <36 h compared to ≥36 hour postpartum hospital stay (81.3 (95% CI 77.9-84.7) versus 72.6 (95% CI 67.9-77.2] hours respectively, (a difference in score of 8.7 [95% CI 2.8-14.6]; p = 0.004). Reliability: ObsQoR-10 demonstrated good internal consistency (Cronbach's alpha = 0.82 and inter-item correlation = 0.32) good split-half reliability (Spearman-Brown Prophesy Reliability Estimate = 0.88) and excellent test-re-test reliability (intra-class correlation coefficient of 0.86 [95% CI 0.72-0.93]). Feasibility: All women completed the survey with a median completion time of 2.5 min.Quality of recovery appears to be better following spontaneous compared to operative vaginal delivery. This study also demonstrates that ObsQoR-10 is a valid and reliable tool for use following these delivery modes.

    View details for DOI 10.1016/j.jclinane.2020.109781

    View details for PubMedID 32203873

  • Postpartum recovery: what does it take to get back to a baseline? Current opinion in obstetrics & gynecology Sultan, P. n., Carvalho, B. n. 2020; Publish Ahead of Print

    Abstract

    Limited guidance exists regarding how to assess postpartum recovery. In this article, we discuss various aspects of inpatient and outpatient postpartum recovery.The postpartum period for many women includes sleep deprivation, maternal-neonatal bonding, breastfeeding, and integrating a new life into the family unit. Factors which impact inpatient quality of recovery include pain, nausea or vomiting, dizziness, shivering, comfort, mobilization, ability to hold and feed the baby, personal hygiene maintenance, and feeling in control. Outpatient recovery domains include psychosocial distress, surgical/medical factors, feeding and breast health, psychosocial support, pain, physical function, sleep, motherhood experience, infant health, fatigue, appearance / cosmetic factors, sexual function, and cognition. Postpartum recovery is likely to take longer than six weeks; however, no consensus regarding recovery duration exists among professional societies. Obstetric quality of recovery (ObsQoR) is a recommended measure of inpatient postpartum recovery; however, studies are needed to determine the optimum outpatient recovery assessment tool.Postpartum recovery is an important area that requires clinical and research attention. Future studies should focus on identifying and developing valid, reliable, and responsive measures of recovery as well as tracking and optimizing recovery domains following all delivery modes.http://links.lww.com/COOG/A65.

    View details for DOI 10.1097/GCO.0000000000000684

    View details for PubMedID 33395109

  • Quadratus lumborum block vs. transversus abdominis plane block for caesarean delivery: a systematic review and network meta-analysis. Anaesthesia El-Boghdadly, K. n., Desai, N. n., Halpern, S. n., Blake, L. n., Odor, P. M., Bampoe, S. n., Carvalho, B. n., Sultan, P. n. 2020

    Abstract

    Caesarean delivery is the most commonly performed inpatient surgical procedure globally. Pain after caesarean delivery is moderate to severe if not adequately treated, and is a primary anaesthetic concern for patients. Transversus abdominis plane and quadratus lumborum blocks are fascial plane blocks that have the potential to improve analgesia following caesarean delivery. Although proponents of the quadratus lumborum block suggest that this technique may provide better analgesia compared with transversus abdominis plane block, there are limited data directly comparing these two techniques. We, therefore, performed a systematic review and network meta-analysis to compare transversus abdominis plane and quadratus lumborum block approaches, seeking randomised controlled trials comparing both techniques to each other, or to control, with or without intrathecal morphine. In all, 31 trials with 2188 patients were included and our primary outcome, the cumulative intravenous morphine equivalent consumption at 24 h, was reported in 12 trials. In the absence of intrathecal morphine, transversus abdominis plane and quadratus lumborum blocks were equivalent, and both were superior to control (moderate-quality evidence). In the presence of intrathecal morphine, no differences were found between control, transversus abdominis plane and quadratus lumborum blocks (moderate-quality evidence). Similar results were found for resting and active pain scores at 4-6 h, 8-12 h, 24 h and 36 h, although quadratus lumborum block was associated with lower pain scores at 36 h when compared with transversus abdominis plane block (very low-quality evidence). However, transversus abdominis plane block was associated with a reduced incidence of postoperative nausea and vomiting (moderate-quality evidence) and sedation when compared with inactive control following intrathecal morphine administration (low-quality evidence). There are insufficient data to draw definitive conclusions, but transversus abdominis plane and quadratus lumborum block appear to be superior to control in the absence of intrathecal morphine, but provide limited additional benefit over inactive control when intrathecal morphine is also used.

    View details for DOI 10.1111/anae.15160

    View details for PubMedID 32621529

  • Obstetric Anaesthetists' Association/National Perinatal Epidemiology Unit collaborative project to develop key indicators for quality of care in obstetric anaesthesia: first steps in the right direction. Anaesthesia Carvalho, B., Kinsella, S. M. 2019

    View details for DOI 10.1111/anae.14935

    View details for PubMedID 31797362

  • Evaluation of Electronic Medical Records on Nurses' Time Allocation During Cesarean Delivery. Journal of patient safety Tan, M., Lipman, S., Lee, H., Sie, L., Carvalho, B. 2019; 15 (4): e82–e85

    Abstract

    BACKGROUND: The impact of the electronic medical record (EMR) on nursing workload is not well understood. The objective of this descriptive study was to measure the actual and perceived time that nurses spend on the EMR in the operating room during cesarean births.METHODS: Twenty scheduled cesarean births were observed. An observer timed the circulating nurse's EMR use during each case. Immediately after each case, the nurse completed a questionnaire to estimate EMR time allocation during the case and their desired time allocation for a typical case. They were also asked about time allotted to various activities preoperatively, intraoperatively, and postoperatively for a typical cesarean birth.RESULTS: Mean observed nurse EMR time was 36 ± 12 minutes per case, 40% ± 10% of the duration of the cesarean delivery. Nurses tended to estimate greater time spent on the EMR; the perceived mean proportion of time spent on the EMR (55%) was greater than the actual timed value of 40% (P = 0.020). Nurse's desired amount of time spent on the EMR was 22% ± 15% of the case duration, significantly less than actual time spent on the EMR (P = 0.007).CONCLUSIONS: On average, nurses spent 40% of their intraoperative time on the EMR during cesarean births, and this time burden was distributed across the perioperative period. These findings highlight the time burden of EMRs and suggest that EMR functionality should be better aligned with end-user needs. Future studies are needed to better understand the impacts of intraoperative EMR use on patient safety and patient/nursing/clinician communication.

    View details for DOI 10.1097/PTS.0000000000000467

    View details for PubMedID 29485519

  • Addressing Racial and Ethnic Disparities in Pain Management in the Midst of the Opioid Crisis. Obstetrics and gynecology Bateman, B. T., Carvalho, B. 2019; 134 (6): 1144-1146

    View details for DOI 10.1097/AOG.0000000000003590

    View details for PubMedID 31764722

  • Electrical stimulation test for epidural catheter placement after receiving intrathecal local anesthetic during a combined spinal-epidural technique for Cesarean delivery: confirmation of the spinal nerve root as epidural site of action. Canadian journal of anaesthesia = Journal canadien d'anesthesie Stewart, M., Carvalho, B., Tsui, B. C. 2019

    View details for DOI 10.1007/s12630-019-01516-3

    View details for PubMedID 31686362

  • Virtual reality successfully provides anxiolysis to laboring women undergoing epidural placement. Journal of clinical anesthesia Kist, M., Bekemeyer, Z., Ralls, L., Carvalho, B., Rodriguez, S. T., Caruso, T. J. 2019: 109635

    View details for DOI 10.1016/j.jclinane.2019.109635

    View details for PubMedID 31662229

  • Ocular sonography in pre-eclampsia: a simple technique to detect raised intracranial pressure? International journal of obstetric anesthesia Ortner, C. M., Macias, P., Neethling, E., Krishnamoorthy, V., Carvalho, B., Swanevelder, J. L., Dyer, R. A. 2019

    View details for DOI 10.1016/j.ijoa.2019.09.002

    View details for PubMedID 31704252

  • Prevention of hypotension after spinal anaesthesia for caesarean section: a systematic review and network meta-analysis of randomised controlled trials. Anaesthesia Fitzgerald, J. P., Fedoruk, K. A., Jadin, S. M., Carvalho, B., Halpern, S. H. 2019

    Abstract

    Spinal anaesthesia for caesarean section commonly causes maternal hypotension. This systematic review and network meta-analysis compared methods to prevent hypotension in women receiving spinal anaesthesia for caesarean section. We selected randomised controlled trials that compared an intervention to prevent hypotension with another intervention or inactive control by searching MEDLINE and Embase, Web of Science to December 2018. There was no language restriction. Two reviewers extracted data on trial characteristics, methods and outcomes. We assessed risk of bias for individual trials (Cochrane tool) and quality of evidence (GRADE checklist). We assessed 109 trials (8561 women) and 12 different methods that resulted in 30 direct comparisons. Methods ranked by OR (95%CI) from most effective to least effective were: metaraminol 0.11 (0.04-0.26); norepinephrine 0.13 (0.06-0.28); phenylephrine 0.18 (0.11-0.29); leg compression 0.25 (0.14-0.43); ephedrine 0.28 (0.18-0.43); colloid given before induction of anaesthesia 0.38 (0.24-0.61); angiotensin 2, 0.12 (0.02-0.75); colloid given after induction of anaesthesia 0.52 (0.30-0.90); mephentermine 0.09 (0.01-1.30); crystalloid given after induction of anaesthesia 0.78 (0.46-1.31); and crystalloid given before induction of anaesthesia 1.16 (0.76-1.79). Phenylephrine caused maternal bradycardia compared with control, OR (95%CI) 0.23 (0.07-0.79). Ephedrine lowered umbilical artery pH more than phenylephrine, standardised mean difference (95%CI) 0.78 (0.47-1.49). We conclude that vasopressors should be given to healthy women to prevent hypotension during caesarean section with spinal anaesthesia.

    View details for DOI 10.1111/anae.14841

    View details for PubMedID 31531852

  • Evaluation of the impact of enhanced recovery after surgery protocol implementation on maternal outcomes following elective cesarean delivery. International journal of obstetric anesthesia Kleiman, A. M., Chisholm, C. A., Dixon, A. J., Sariosek, B. M., Thiele, R. H., Hedrick, T. L., Carvalho, B., Tiouririne, M. 2019

    Abstract

    BACKGROUND: Despite significant improvements in outcomes following non-obstetric surgery with implementation of enhanced recovery after surgery (ERAS) protocols, development of these protocols for cesarean delivery is lacking. We evaluated implementation of an ERAS protocol for patients undergoing elective cesarean delivery, specifically the effect on opioid consumption, pain scores and length of stay as well as complications and re-admissions.METHODS: An ERAS protocol was developed and implemented for women undergoing elective cesarean delivery. The protocol construction included specific evidence-based items applicable to peripartum management and these were grouped into the three major phases of patient care: antepartum, intrapartum and postpartum. A before-and-after study design was used to compare maternal outcomes. To account for confounders between groups, a propensity matched scoring analysis was used. The primary outcome was postpartum opioid use in mg-morphine equivalents (MMEQ).RESULTS: We included 357 (n=196 before; n=161 after) women who underwent elective cesarean delivery. A significant difference in opioid consumption (28.4 ± 24.1 vs 46.1 ± 37.0 MMEQ, P <0.001) and in per-day postoperative opioid consumption (10.9 ± 8.7 vs 15.1 ± 10.3 MMEQ, P <0.001), lower peak pain scores (7 [5-9] vs 8 [7-9], P=0.007) and a shorter hospital length of stay (2.5 ± 0.5 vs 2.9 ± 1.2 days, P <0.001) were found after the introduction of the ERAS protocol.CONCLUSIONS: Implementation of ERAS protocols for elective cesarean delivery is associated with significant improvements in analgesic and recovery outcomes. These improvements in quality of care suggest ERAS protocols should be considered for elective cesarean delivery.

    View details for DOI 10.1016/j.ijoa.2019.08.004

    View details for PubMedID 31522935

  • Evaluation of patient-reported outcome measures of functional recovery following caesarean section: a systematic review using the consensus-based standards for the selection of health measurement instruments (COSMIN) checklist. Anaesthesia Sharawi, N., Klima, L., Shah, R., Blake, L., Carvalho, B., Sultan, P. 2019

    Abstract

    We performed a systematic review using 'consensus-based standards for the selection of health measurement instruments' (COSMIN) criteria to identify and evaluate the quality of patient-reported outcome measures (PROM) instruments that have been utilised to assess functional recovery following caesarean section, and determine the optimal instrument for use in this setting. A literature search was performed using five databases. Studies were included if a psychometrically validated instrument was used to assess functional recovery following caesarean section. The COSMIN appraisal checklist was utilised to: assess the quality of included studies reporting PROMs; determine psychometric quality of instruments; and identify the most promising instruments for use after caesarean section. We identified 13 PROMs used to assess the quality of recovery after caesarean section in 20 studies that included 9214 patients. All PROMs contained between two and seven domains. Five out of the 13 PROMs were specific to postpartum recovery. Only two of these PROM instruments were specifically designed for use after caesarean section (Obstetric Quality of Recovery-11 and Recovery from Caesarean SectionScale). We found very few adequate measures of functional recovery following caesarean section. Overall, the Obstetric Quality of Recovery-11 achieved the highest COSMIN standards for any PROM. Future development of PROMs for use after caesarean section should include multiple domains, and undergo validation as outlined by the COSMIN criteria.

    View details for DOI 10.1111/anae.14807

    View details for PubMedID 31429919

  • Society for Obstetric Anesthesia and Perinatology Consensus Statement: Monitoring Recommendations for Prevention and Detection of Respiratory Depression Associated With Administration of Neuraxial Morphine for Cesarean Delivery Analgesia ANESTHESIA AND ANALGESIA Bauchat, J. R., Weiniger, C. F., Sultan, P., Habib, A. S., Ando, K., Kowalczyk, J. J., Kato, R., George, R. B., Palmer, C. M., Carvalho, B. 2019; 129 (2): 458–74
  • The comparative accuracy of a handheld and console ultrasound device for neuraxial depth and landmark assessment INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Seligman, K. M., Weiniger, C. F. 2019; 39: 68–73
  • Evaluation of the Obstetric Quality-of-Recovery score (ObsQoR-11) following non-elective caesarean delivery INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Ciechanowicz, S., Howie, R., Heppolette, C., Nakhjavani, B., Carvalho, B., Sultan, P. 2019; 39: 51–59
  • Preoperative Fasting Times for Patients Undergoing Caesarean Delivery: Before and After a Patient Educational Initiative. Turkish journal of anaesthesiology and reanimation Yurashevich, M., Chow, A., Kowalczyk, J. J., Traynor, A. J., Carvalho, B. 2019; 47 (4): 282-286

    Abstract

    Prolonged preoperative fasting may lead to dehydration, hypoglycaemia, ketoacidosis and delayed recovery. We hypothesised that a patient educational initiative would decrease our preoperative fasting periods for elective caesarean delivery.This was an observational quality improvement impact study. Elective caesarean patients who delivered during our study period were included in the study, 40 patients in the pre-intervention and 40 patients in the post-intervention groups. Only English-speaking patients were included. We developed a patient educational pamphlet outlining preoperative fasting and analgesic expectations for caesarean delivery that was given to every patient at her preoperative anaesthesia consultation. The pamphlet included the American Society of Anesthesiologists' preoperative fasting and enhanced recovery carbohydrate drink recommendations. The primary outcome measure was intended fasting duration for liquids (defined as time from last reported liquid consumption to scheduled caesarean delivery) before and after the patient educational initiative. Secondary outcomes included solid fasting time, types of liquids and solids consumed.The intended median (interquartile range) fasting time for liquids decreased from 10 (8.9-12) h to 3.5 (2.5-10) h (p<0.001). The fasting period for solids was not significantly different: 12.5 (10.5-14) h pre- versus 12.4 (10.6-14) h post-pamphlet introduction (p=0.384). Despite the recommendation, only 22.5% consumed a carbohydrate-containing drink with a modest decrease in water consumption (87.5% before and 67.5% after; p=0.009).A patient educational pamphlet significantly reduced fasting time for clear liquids. Future studies are needed to determine what barriers limited adherence to the recommended carbohydrate-containing drink consumption.

    View details for DOI 10.5152/TJAR.2019.95770

    View details for PubMedID 31380508

    View details for PubMedCentralID PMC6645844

  • Preoperative Fasting Times for Patients Undergoing Caesarean Delivery: Before and After a Patient Educational Initiative TURKISH JOURNAL OF ANAESTHESIOLOGY AND REANIMATION Yurashevich, M., Chow, A., Kowalczyk, J. J., Traynor, A. J., Carvalho, B. 2019; 47 (4): 282–86
  • International consensus statement on the use of uterotonic agents during caesarean section. Anaesthesia Heesen, M., Carvalho, B., Carvalho, J. C., Duvekot, J. J., Dyer, R. A., Lucas, D. N., McDonnell, N., Orbach-Zinger, S., Kinsella, S. M. 2019

    Abstract

    It is routine to give a uterotonic drug following delivery of the neonate during caesarean section. However, there is much heterogeneity in the relevant research, which has largely been performed in low-risk elective cases or women with uncomplicated labour. This is reflected in considerable variation in clinical practice. There are significant differences between dose requirements during elective and intrapartum caesarean section. Standard recommended doses are higher than required, with the potential for acute cardiovascular adverse effects. We recommend a small initial bolus dose of oxytocin, followed by a titrated infusion. The recommended doses of oxytocin may have to be increased in women with risk factors for uterine atony. Carbetocin at equipotent doses to oxytocin has similar actions, while avoiding the requirement for a continuous infusion after the initial dose and reducing the need for additional uterotonics. As with oxytocin, carbetocin dose requirements are higher for intrapartum caesarean sections. A second-line agent should be considered early if oxytocin/carbetocin fails to produce good uterine tone. Women with cardiac disease may be very sensitive to the adverse effects of oxytocin and other uterotonics, and their management needs to be individualised.

    View details for DOI 10.1111/anae.14757

    View details for PubMedID 31347151

  • Supraglottic Airway Rescue After Failed Fiberoptic Intubation in a Patient With Osteogenesis Imperfecta: A Case Report A & A PRACTICE Sutton, C., Carvalho, B. 2019; 13 (1): 7–9
  • Determinants of women's dissatisfaction with anaesthesia care in labour and delivery. Anaesthesia Yurashevich, M., Carvalho, B., Butwick, A. J., Ando, K., Flood, P. D. 2019

    Abstract

    Patient-centred care and factors associated with patient satisfaction with anaesthesia have been widely studied. However, the most important considerations in the setting of obstetric anaesthesia are uncertain. Identification of, and addressing, factors that contribute to patient dissatisfaction may improve quality of care. We sought to identify factors associated with<100% satisfaction with obstetric anaesthesia care. At total of 4297 women treated by anaesthetists provided satisfaction data 24h after vaginal and 48h after caesarean delivery. As 78% of women were 100% satisfied, we studied factors associated with the dichotomous variable, 100% satisfied vs. < 100% satisfied. We evaluated patient characteristics and peripartum factors using multivariable sequential logistic regression. The following factors were strongly associated with maternal dissatisfaction after vaginal delivery: pain intensity during the first stage of labour; pain intensity during the second stage of labour; postpartum pain intensity; delay >15min in providing epidural analgesia and postpartum headache (all p<0.0001). Pruritus (p=0.005) also contributed to dissatisfaction after vaginal delivery, whereas non-Hispanic ethnicity was negatively associated with dissatisfaction (p=0.01). After caesarean delivery, the intensity of postpartum pain (p<0.0001), headache (p=0.001) and pruritus (p=0.001) were linked to dissatisfaction. Hispanic ethnicity also had a negative relationship with dissatisfaction after caesarean delivery (p=0.005). Thus, inadequate or delayed analgesia and treatment-related side-effects are associated with maternal dissatisfaction with obstetric anaesthesia care. Development of protocols to facilitate identification of ineffective analgesia and provide an appropriate balance between efficacy and side-effects, are important goals to optimise maternal satisfaction.

    View details for DOI 10.1111/anae.14756

    View details for PubMedID 31264207

  • Pain relief during labour. Lancet (London, England) Lozada, M. J., Weiniger, C. F., Carvalho, B., Bauchat, J. R. 2019

    View details for DOI 10.1016/S0140-6736(19)30710-X

    View details for PubMedID 31262493

  • Impact of intra-operative dexamethasone after scheduled cesarean delivery: a retrospective study. International journal of obstetric anesthesia Nanji, J. A., Guo, N., Riley, E. T., Carvalho, B. 2019

    Abstract

    BACKGROUND: Dexamethasone is an effective analgesic and anti-emetic in patients undergoing many surgical procedures but its effects on pain after cesarean delivery are poorly studied. The aim of this study was to evaluate if routine intra-operative administration of dexamethasone improved analgesia and decreased postoperative nausea and vomiting after scheduled cesarean delivery.METHODS: Electronic medical record data for scheduled cesarean deliveries performed under neuraxial anesthesia, before and after a practice change that introduced the routine use of intravenous dexamethasone 4 mg, were obtained. Patients were analyzed based on whether they received routine care (n=182) or also received dexamethasone (n=187). The primary outcome was time to first opioid use. Secondary outcomes included postoperative opioid consumption, pain scores, incidence and treatment of postoperative nausea and vomiting, satisfaction and length of stay.RESULTS: There was no significant difference between groups in median time to first postoperative opioid administration (15.8 [3.4-48.0] h routine care vs 14.7 [3.2-38.8] h routine care plus dexamethasone, P=0.08). There were no significant differences in any secondary outcomes.CONCLUSIONS: This impact study involving more than 360 patients suggests that routine administration of intra-operative intravenous dexamethasone 4 mg does not provide additional analgesic benefit after scheduled cesarean delivery, in the context of a multimodal postoperative analgesic regimen. Studies are required to determine if a larger dose or repeated administration influence postoperative analgesia or side effects, or whether certain subsets of patients may benefit.

    View details for DOI 10.1016/j.ijoa.2019.06.006

    View details for PubMedID 31345664

  • Differential Dynamics of the Maternal Immune System in Healthy Pregnancy and Preeclampsia. Frontiers in immunology Han, X., Ghaemi, M. S., Ando, K., Peterson, L. S., Ganio, E. A., Tsai, A. S., Gaudilliere, D. K., Stelzer, I. A., Einhaus, J., Bertrand, B., Stanley, N., Culos, A., Tanada, A., Hedou, J., Tsai, E. S., Fallahzadeh, R., Wong, R. J., Judy, A. E., Winn, V. D., Druzin, M. L., Blumenfeld, Y. J., Hlatky, M. A., Quaintance, C. C., Gibbs, R. S., Carvalho, B., Shaw, G. M., Stevenson, D. K., Angst, M. S., Aghaeepour, N., Gaudilliere, B. 2019; 10: 1305

    Abstract

    Preeclampsia is one of the most severe pregnancy complications and a leading cause of maternal death. However, early diagnosis of preeclampsia remains a clinical challenge. Alterations in the normal immune adaptations necessary for the maintenance of a healthy pregnancy are central features of preeclampsia. However, prior analyses primarily focused on the static assessment of select immune cell subsets have provided limited information for the prediction of preeclampsia. Here, we used a high-dimensional mass cytometry immunoassay to characterize the dynamic changes of over 370 immune cell features (including cell distribution and functional responses) in maternal blood during healthy and preeclamptic pregnancies. We found a set of eight cell-specific immune features that accurately identified patients well before the clinical diagnosis of preeclampsia (median area under the curve (AUC) 0.91, interquartile range [0.82-0.92]). Several features recapitulated previously known immune dysfunctions in preeclampsia, such as elevated pro-inflammatory innate immune responses early in pregnancy and impaired regulatory T (Treg) cell signaling. The analysis revealed additional novel immune responses that were strongly associated with, and preceded the onset of preeclampsia, notably abnormal STAT5ab signaling dynamics in CD4+T cell subsets (AUC 0.92, p = 8.0E-5). These results provide a global readout of the dynamics of the maternal immune system early in pregnancy and lay the groundwork for identifying clinically-relevant immune dysfunctions for the prediction and prevention of preeclampsia.

    View details for DOI 10.3389/fimmu.2019.01305

    View details for PubMedID 31263463

    View details for PubMedCentralID PMC6584811

  • Differential Dynamics of the Maternal Immune System in Healthy Pregnancy and Preeclampsia FRONTIERS IN IMMUNOLOGY Han, X., Ghaemi, M. S., Ando, K., Peterson, L. S., Ganio, E. A., Tsai, A. S., Gaudilliere, D. K., Stelzer, I. A., Einhaus, J., Bertrand, B., Stanley, N., Culos, A., Tanada, A., Hedou, J., Tsai, E. S., Fallahzadeh, R., Wong, R. J., Judy, A. E., Winn, V. D., Druzins, M. L., Blumenfeld, Y. J., Hlatky, M. A., Quaintance, C. C., Gibbs, R. S., Carvalho, B., Shaw, G. M., Stevenson, D. K., Angst, M. S., Aghaeepour, N., Gaudilliere, B. 2019; 10
  • Labor Epidural Analgesia to Cesarean Section Anesthetic Conversion Failure: A National Survey. Anesthesiology research and practice Desai, N., Gardner, A., Carvalho, B. 2019; 2019: 6381792

    Abstract

    If conversion of labor epidural analgesia to cesarean delivery anesthesia fails, the anesthesiologist can be confronted with a challenging clinical dilemma. Optimal management of a failed epidural top up continues to be debated in the absence of best practice guidelines.All members of the Obstetric Anaesthetists' Association in the United Kingdom were emailed an online survey in May 2017. It obtained information on factors influencing the decision to utilize an existing labor epidural for cesarean section and, if epidural top up resulted in no objective sensory block, bilateral T10 sensory block, or unilateral T6 sensory block, factors influencing the management and selection of anesthetic technique. Differences in management options between respondents were compared using the chi-squared test.We received 710 survey questionnaires with an overall response rate of 41%. Most respondents (89%) would consider topping up an existing labor epidural for a category-one cesarean section. In evaluating whether or not to top up an existing labor epidural, the factors influencing decision-making were how effective the epidural had been for labor pain (99%), category of cesarean section (73%), and dermatomal level of blockade (61%). In the setting of a failed epidural top up, the most influential factors determining further anesthetic management were the category of cesarean section (92%), dermatomal level of blockade (78%), and the assessment of maternal airway. Spinal anesthesia was commonly preferred if an epidural top up resulted in no objective sensory block (74%), bilateral T10 sensory block (57%), or unilateral T6 sensory block (45%). If the sensory block level was higher or unilateral, then a lower dose of intrathecal local anesthetic was selected and alternative options such as combined-spinal epidural and general anesthesia were increasingly favored.Our survey revealed variations in the clinical management of a failed epidural top up for cesarean delivery, suggesting guidelines to aid decision-making are needed.

    View details for DOI 10.1155/2019/6381792

    View details for PubMedID 31281354

    View details for PubMedCentralID PMC6589285

  • Intra-aortic Balloon Pump for Cesarean Hysterectomy and Massive Hemorrhage in a Parturient with Placenta Accreta and Pulmonary Embolus. Journal of medical ultrasound Riley, E. T., Akbar, K., Carvalho, B. 2019; 27 (2): 104-106

    Abstract

    During cesarean hysterectomy for a placenta accreta, a 36-year-old parturient underwent a massive resuscitation for profound bleeding and also suffered a pulmonary embolus leading to cardiac arrest. Chest compressions and epinephrine were required for resucitation. When surgery was complete, she was taken to the intensive care unit on an epinephrine infusion and inhaled nitric oxide but was brought back to the operating room after 3 h for surgical exploration. Echocardiography revealed a poorly contracting left ventricle, and an intra-aortic balloon pump was inserted. She gradually recovered full function and was discharged home after 35 days.

    View details for DOI 10.4103/JMU.JMU_84_18

    View details for PubMedID 31316222

    View details for PubMedCentralID PMC6607871

  • Society for Obstetric Anesthesia and Perinatology Consensus Statement: Monitoring Recommendations for Prevention and Detection of Respiratory Depression Associated With Administration of Neuraxial Morphine for Cesarean Delivery Analgesia. Anesthesia and analgesia Bauchat, J. R., Weiniger, C. F., Sultan, P., Habib, A. S., Ando, K., Kowalczyk, J. J., Kato, R., George, R. B., Palmer, C. M., Carvalho, B. 2019

    Abstract

    The majority of women undergoing cesarean delivery in the United States receive neuraxial morphine, the most effective form of postoperative analgesia for this surgery. Current American Society of Anesthesiologists (ASA) and American Society of Regional Anesthesia and Pain Medicine (ASRA) recommend respiratory monitoring standards following neuraxial morphine administration in the general surgical population that may be too frequent and intensive when applied to the healthy obstetric population receiving a single dose of neuraxial morphine at the time of surgery. There is limited evidence to support or guide the optimal modality, frequency, and duration of respiratory monitoring in the postoperative cesarean delivery patient receiving a single dose of neuraxial morphine. Consistent with the mission of the Society for Obstetric Anesthesia and Perinatology (SOAP) to improve outcomes in pregnancy for women and neonates, the purpose of this consensus statement is to encourage the use of this highly effective analgesic technique while promoting safe practice and patient-centered care. The document aims to reduce unnecessary interruptions from respiratory monitoring in healthy mothers while focusing vigilance on monitoring in those women at highest risk for respiratory depression following neuraxial morphine administration. This consensus statement promotes the use of low-dose neuraxial morphine and multimodal analgesia after cesarean delivery, gives perspective on the safety of this analgesic technique in healthy women, and promotes patient risk stratification and perioperative risk assessment to determine and adjust the intensity, frequency, and duration of respiratory monitoring.

    View details for PubMedID 31082964

  • Centers of Excellence for Anesthesia Care of Obstetric Patients. Anesthesia and analgesia Carvalho, B., Mhyre, J. M. 2019; 128 (5): 844–46

    View details for PubMedID 30994544

  • Centers of Excellence for Anesthesia Care of Obstetric Patients ANESTHESIA AND ANALGESIA Carvalho, B., Mhyre, J. M. 2019; 128 (5): 844–46
  • Assessing the Association Between Blood Loss and Postoperative Hemoglobin After Cesarean Delivery: A Prospective Study of 4 Blood Loss Measurement Modalities ANESTHESIA AND ANALGESIA Fedoruk, K., Seligman, K. M., Carvalho, B., Butwick, A. J. 2019; 128 (5): 926–32
  • In vitro intravenous fluid co-load rates with and without an intravenous fluid warming device INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Kowalczyk, J. J., Yurashevich, M., Austin, N., Carvalho, B. 2019; 38: 149–50
  • Impact of patient choice for different postcesarean delivery analgesic protocols on opioid consumption: a randomized prospective clinical trial REGIONAL ANESTHESIA AND PAIN MEDICINE Carvalho, B., Sutton, C., Kowalczyk, J. J., Flood, P. 2019; 44 (5): 578–85
  • Personalized analgesic management for cesarean delivery. International journal of obstetric anesthesia Carvalho, B., Habib, A. S. 2019

    Abstract

    Current pain and analgesic management strategies apply a standardized one-size-fits-all approach to all women undergoing cesarean delivery. These standardized protocols do not account for significant variability in women's pain and may lead to under-treatment in patients with high analgesic needs and overtreatment, associated with increased analgesic-related side effects, in women with low analgesic needs and higher analgesic drug sensitivity. Pre-operative identification of patients at risk of developing severe pain might allow clinicians to optimize care by offering personalized, stratified or targeted analgesic treatment protocols. Pre-operative pain prediction tools are only of moderate value in this regard. Pain reporting during local anesthetic infiltration and answering simple rating questions about anticipated pain and analgesic needs are the easiest tools to apply and show some promise for post cesarean delivery pain prediction. Patient-driven analgesic dose and protocol selection (based on individual preferences for pain relief and for avoidance of side effects after cesarean delivery) may optimally balance individual pain needs and side effect concerns compared to standardized postoperative pain treatment protocols. Individualized or stratified post-discharge opioid prescribing practices have been shown to reduce unnecessary opioid analgesic prescriptions and consumption, so should be implemented routinely. Outcomes other than pain and analgesic use, including recovery measures and maternal satisfaction metrics, should be considered when evaluating personalized or patient-selected pain treatment protocols.

    View details for DOI 10.1016/j.ijoa.2019.02.124

    View details for PubMedID 31227220

  • Intra-aortic Balloon Pump for Cesarean Hysterectomy and Massive Hemorrhage in a Parturient with Placenta Accreta and Pulmonary Embolus JOURNAL OF MEDICAL ULTRASOUND Riley, E. T., Akbar, K., Carvalho, B. 2019; 27 (2): 104–6
  • Impact of patient choice for different postcesarean delivery analgesic protocols on opioid consumption: a randomized prospective clinical trial. Regional anesthesia and pain medicine Carvalho, B., Sutton, C. D., Kowalczyk, J. J., Flood, P. D. 2019

    Abstract

    BACKGROUND: Choice of postcesarean delivery analgesic protocol may improve pain experience and reduce analgesic requirements.METHODS: Cesarean delivery patients were randomly assigned either to choose their postcesarean delivery analgesia protocol or to have no choice and receive routine care. Choices were low (50 mug intrathecal morphine), medium (identical to routine care: 150 mug intrathecal morphine), or high (300 mug intrathecal morphine with 600mg oral gabapentin). All groups received scheduled acetaminophen and ibuprofen. The primary outcome was oxycodone requirements 0-48hours postdelivery in those offered versus not offered a choice.RESULTS: Of 160 women enrolled, 120 were offered a choice and 40 were not offered a choice. There was no difference in oxycodone requirements or pain associated with choice, but those who had a choice expressed more satisfaction than those who did not have a choice (mean (95%CI) difference 5% (0% to 10 %), p=0.005). In the choice group, the high dose group required more oxycodone (5 (0 to 15)mg 0-24hours after delivery and 15 (10 to 25) mg at 24-48hours; p=0.05 and p=0.001) versus the low and medium groups. The low dose group had less pruritus (p=0.001), while the high dose group had more vomiting (p=0.01) requiring antiemetic treatment (p=0.04).CONCLUSION: Having a choice compared with no choice routine care did not reduce oxycodone requirements or pain scores. However, women have insight into their analgesic needs; women offered a choice and who chose the higher dose analgesic protocol required more oxycodone, and women who chose the lower dose protocol required less oxycodone. Despite providing additional analgesic (six times more intrathecal morphine plus gabapentin in high dose vs low dose protocols), we still did not equalize postcesarean oxycodone requirement differences between groups.TRIAL REGISTRATION NUMBER: NCT02605187.

    View details for PubMedID 30867278

  • Prospective Observational Investigation of Capnography and Pulse Oximetry Monitoring After Cesarean Delivery With Intrathecal Morphine ANESTHESIA AND ANALGESIA Weiniger, C. F., Akdagli, S., Turvall, E., Deutsch, L., Carvalho, B. 2019; 128 (3): 513–22

    Abstract

    Intrathecal morphine provides excellent analgesia after cesarean delivery; however, respiratory events such as apnea, bradypnea, and hypoxemia have been reported. The primary study aim was to estimate the number of apneas per subject, termed "apnea alert events" (AAEs) defined by no breath for 30-120 seconds, using continuous capnography in women who underwent cesarean delivery.We performed a prospective, observational study with institutional review board approval of women who underwent cesarean delivery with spinal anesthesia containing 150-µg intrathecal morphine. A STOP-Bang obstructive sleep apnea assessment was administered to all women. Women were requested to use continuous capnography and pulse oximetry for 24 hours after cesarean delivery. Nasal sampling cannula measured end-tidal carbon dioxide (EtCO2) and respiratory rate (RR), and oxygen saturation (SpO2) as measured by pulse oximetry. Capnography data were defined as "valid" when EtCO2 >10 mm Hg, RR >5 breaths per minute (bpm), SpO2 >70%, or during apnea (AAE) defined as "no breath" (EtCO2, <5 mm Hg) for 30-120 seconds. Individual respiratory variable alerts were 10-second means of EtCO2 <10 mm Hg, RR <8 bpm, and SpO2 <94%. Nurse observations of RR (hourly and blinded to capnography) are reported.We recruited 80 women, mean (standard deviation [SD]) 35 (5) years, 47% body mass index >30 kg/m/weight >90 kg, and 11% with suspected obstructive sleep apnea (known or STOP-Bang score >3). The duration of normal capnography and pulse oximetry data was mean (SD) (range) 8:28 (7:51) (0:00-22:32) and 15:08 (6:42) (1:31-23:07) hours:minutes, respectively; 6 women did not use the capnography. There were 198 AAEs, mean (SD) duration 57 (27) seconds experienced by 39/74 (53%) women, median (95% confidence interval for median) (range) 1 (0-1) (0-29) per subject. Observation of RR by nurses was ≥14 bpm at all time-points for all women, r = 0.05 between capnography and nurse RR (95% confidence interval, -0.04 to 0.14). There were no clinically relevant adverse events for any woman. Sixty-five women (82%) had complaints with the capnography device, including itchy nose, nausea, interference with nursing baby, and overall inconvenience.We report 198 AAEs detected by capnography among women who underwent cesarean delivery after receiving intrathecal morphine. These apneas were not confirmed by the intermittent hourly nursing observations. Absence of observer verification precludes distinction between real, albeit nonclinically significant alerts with capnography versus false apneas. Discomfort with the nasal sampling cannula and frequent alerts may impact capnography application after cesarean delivery. No clinically relevant adverse events occurred.

    View details for PubMedID 29958217

  • Population Pharmacokinetic Modeling to Evaluate Standard Magnesium Sulfate Treatments and Alternative Dosing Regimens for Women With Preeclampsia JOURNAL OF CLINICAL PHARMACOLOGY Du, L., Wenning, L., Migoya, E., Xu, Y., Carvalho, B., Brookfield, K., Witjes, H., de Greef, R., Lumbiganon, P., Sangkomkamhang, U., Titapant, V., Duley, L., Long, Q., Oladapo, O. T. 2019; 59 (3): 374–85

    View details for DOI 10.1002/jcph.1328

    View details for Web of Science ID 000459827100008

  • Evaluation of the Obstetric Quality-of-Recovery score (ObsQoR-11) following non-elective caesarean delivery. International journal of obstetric anesthesia Ciechanowicz, S., Howle, R., Heppolette, C., Nakhjavani, B., Carvalho, B., Sultan, P. 2019

    Abstract

    BACKGROUND: Few robust scoring tools exist to assess recovery following caesarean delivery (CD). We evaluated a new obstetric quality of recovery score (ObsQoR-11, initially formulated for elective CD) following non-elective CD.METHODS: ObsQoR-11 questionnaires were completed by women at day one post non-elective CD. Convergent validity was assessed by correlation of ObsQoR-11 with a 100 mm numerical rating scale (NRS) of general health status; discriminant validity by correlation with good versus poor recovery (NRS of ≥70 vs. <70 mm, respectively); and content validity by correlation with length of stay (LOS), CD category, parity, gestation, previous CD, duration, blood loss, haemoglobin, age and body mass index. Cronbach's alpha, inter-item, split-half and test-retest correlation assessed reliability. Feasibility was tested by recruitment rate and time for ObsQoR-11 completion.RESULTS: 100 women completed ObsQoR-11 at 24 h and 20 women repeated it at 25 h. ObsQoR-11 correlated strongly with NRS (r = 0.72 [95% CI 0.61 to 0.81], P <0.0001); discriminated well between good versus poor recovery (median [IQR] score 97 [86.5-101] versus 64 [50.5-78.5], P <0.0001); correlated to LOS (r = -0.24 [-0.42 to -0.04], P=0.02) and parity (r = 0.24 [0.04 to 0.42], P=0.02). Reliability was acceptable: Cronbach's alpha 0.75; inter-item correlation >0.15; split-half reliability 0.96; and intra-class correlation >0.6; no floor or ceiling effects. One hundred percent completed the ObsQoR-11 (median [IQR] completion time 117 [89-156] s).CONCLUSIONS: ObsQoR-11 is valid and reliable in assessing recovery after non-elective CD. Further research should assess generalisability and use following vaginal delivery.

    View details for PubMedID 30885691

  • The Crystalloid Co-Load: Clinically as Effective as Colloid Preload for Preventing Hypotension from Spinal Anaesthesia for Caesarean Delivery. Turkish journal of anaesthesiology and reanimation Riley, E. T., Mangum, K., Carvalho, B., Butwick, A. J. 2019; 47 (1): 35-40

    Abstract

    Colloid preloading diminishes post-spinal hypotension. However, whether colloid preloading is superior to crystalloid co-loading is uncertain. In this retrospective study, we compared the effects of a colloid preload versus a crystalloid co-load on vasopressor requirements and maternal haemodynamics among women undergoing elective caesarean delivery (CD) with spinal anaesthesia.We extracted data from the medical records of 160 healthy women who underwent elective CD with spinal anaesthesia at an academic obstetric centre before and after an institutional fluid-loading protocol change. Patients received a 500 mL 6% hydroxyethyl starch preload or a 1000 mL crystalloid co-load. The primary outcome was the total phenylephrine dose administered from spinal block placement to delivery.Our cohort comprised 79 women in the colloid group and 77 women in the crystalloid group. The mean phenylephrine use was significantly lower in the colloid group than in the crystalloid group (489±403 μg vs. 647±464 μg, respectively, p=0.02). The maximal drop in systolic blood pressure was greater in the colloid group than in the crystalloid group (36±20 mmHg vs. 29±16 mmHg, respectively, p=0.02). There were no clinically significant differences between the groups in heart rate, blood loss, temperature and Apgar scores.Vasopressor use was lower in colloid preloading than in crystalloid co-loading. However, differences in all outcome measures were minimal and likely clinically insignificant, suggesting that both fluid-loading techniques are appropriate to use for the prevention of spinal hypotension in women undergoing CD.

    View details for DOI 10.5152/TJAR.2018.76402

    View details for PubMedID 31276109

    View details for PubMedCentralID PMC6598662

  • The Crystalloid Co-Load: Clinically as Effective as Colloid Preload for Preventing Hypotension from Spinal Anaesthesia for Caesarean Delivery TURKISH JOURNAL OF ANAESTHESIOLOGY AND REANIMATION Riley, E. T., Mangum, K., Carvalho, B., Butwick, A. J. 2019; 47 (1): 35–40
  • Supraglottic Airway Rescue After Failed Fiberoptic Intubation in a Patient With Osteogenesis Imperfecta: A Case Report. A&A practice Sutton, C. D., Carvalho, B. 2019

    Abstract

    We describe the management of a pregnant patient with osteogenesis imperfecta with a history of numerous fractures, severe scoliosis, and anticipated difficult airway. Her pregnancy was complicated by progressive shortness of breath and a fetal diagnosis of osteogenesis imperfecta. Spine anatomy precluded neuraxial anesthesia. Cesarean delivery was performed under general anesthesia at 34 weeks. Immediately after awake fiberoptic intubation and induction of general anesthesia, capnography waveform was lost with rapid profound oxygen desaturation. A supraglottic airway device was placed, oxygenation maintained with supraglottic airway and positive pressure ventilation throughout case, and the baby was delivered with Apgars of 8 and 9.

    View details for PubMedID 30694815

  • The comparative accuracy of a handheld and console ultrasound device for neuraxial depth and landmark assessment. International journal of obstetric anesthesia Carvalho, B., Seligman, K. M., Weiniger, C. F. 2019

    Abstract

    BACKGROUND: The study aimed to compare the accuracy of epidural depth estimation of a handheld ultrasound device, with an integrated algorithm that estimates epidural depth (AU; Accuro, Rivanna Medical), to that of a console ultrasound machine (GU; GE LOGICTM S8).METHODS: Women requesting labor epidural analgesia consented to this prospective cohort study. The L2/3, L3/4, and L4/5 interspaces and the respective depths to the epidural space were identified, marked and measured using an AU and GU. An anesthesia provider who was blinded to ultrasound depth measurements performed epidural analgesia at one of the ultrasound identified insertion points, and recorded the Tuohy needle depth at loss-of-resistance. Bland Altman analysis was used to measure the agreement between the epidural depths measured by the AU and GU.RESULTS: A total of 47 women were analyzed. The mean ± standard deviation body mass index of the study cohort was 29 ± 5 kg/m2 [range 23-45]. The mean difference between the epidural depths measured by the AU and GU was -0.29 cm [95% limit of agreement 0.50 to -0.91]. The mean difference between the depth to the epidural space measured by the GU versus the needle depth was -0.33 cm [95% CI -0.49 to -0.16]. The previously reported AU versus needle depth was -0.61 cm [95% CI -0.79 to -0.44].CONCLUSION: The AU and GU provided comparable epidural depth estimates. The AU device may be a reasonable alternative to more sophisticated ultrasound devices in determining the epidural space and depth in a non-obese obstetric population.

    View details for PubMedID 30770208

  • Prospective observational investigation of body habitus measurements and relationship to epidural depth in term pregnant women. Acta anaesthesiologica Scandinavica Weiniger, C. F., Cohen, A. n., Aptekman, B. n., Carvalho, B. n. 2019

    Abstract

    High body mass index (BMI) can predict difficult neuraxial block, however fat distribution may also be important. The primary study aim was to identify body habitus and fat distribution measurements that correlated with ultrasound measured epidural depth. We hypothesized that measurements such as midarm and subscapular fatpad thicknesses and length of cervical spine may correlate better with ultrasound measured epidural depth than a global measure of BMI.Prospective IRB approved study of term pregnant women requiring neuraxial block. We measured height, weight (BMI, kg/m2 ), subscapular, midarm fatpad thickness (digital caliper, mm), vertebral column length (C7 to sacral hiatus, cm) and epidural depth (ultrasound, mm). Four experts assessed photographs to assign anticipated difficult neuraxial block in sitting and lateral positions (5-point Likert scale, 1=very easy, 5=very difficult).131 women completed body habitus measurements. Measured mean (standard deviation) BMI was 30.3 (5.4) kg/m2 . Measured BMI, subscapular fatpad and midarm fatpad thickness were significantly correlated with ultrasound depth to epidural space (R-square 0.733, 0.626 and 0.633, respectively, p<0.0001) but vertebral column length was not. The experts had a high level of agreement (Cronbach's Alpha >0.7) for assessment of anticipated difficult block in the sitting and lateral positions however anticipated difficult block was not correlated with epidural depth measured by ultrasound for sitting position, R-square=-0.015, p=0.87; and lateral position, R-square=-0.087, p=0.33.Measurements of body habitus and fat distribution were no better than measured BMI to anticipate greater ultrasound measured depth to epidural space.

    View details for DOI 10.1111/aas.13544

    View details for PubMedID 31891434

  • Addressing Racial and Ethnic Disparities in Pain Management in the Midst of the Opioid Crisis. Obstetrics and gynecology Bateman, B. T., Carvalho, B. n. 2019

    View details for DOI 10.1097/AOG.0000000000003590

    View details for PubMedID 31698386

  • Impact of a post-cesarean analgesia order-set with split doses of oral opioids Nanji, J. A., Guo, N., Riley, E. T., Carvalho, B. MOSBY-ELSEVIER. 2019: S622–S623
  • Development and evaluation of an obstetric quality-of-recovery score (ObsQoR-11) after elective Caesarean delivery. British journal of anaesthesia Ciechanowicz, S., Setty, T., Robson, E., Sathasivam, C., Chazapis, M., Dick, J., Carvalho, B., Sultan, P. 2019; 122 (1): 69–78

    Abstract

    BACKGROUND: Whilst validated quality-of-recovery (QoR) tools exist for general surgery, there is no specific obstetric equivalent. We aimed to develop and evaluate a modified QoR score after elective Caesarean delivery.METHODS: Twenty-two obstetric specific items were selected following review and modification of the QoR-40 survey by 16 experts and interviews with 50 stakeholders. Item selection was based on relevance to Caesarean delivery and endorsement by >66% of stakeholders. Items were tested on women pre-delivery, at 24 h, and 25 h post-delivery. An 11-item obstetric-specific QoR score (ObsQoR-11) was created based on correlation with a numerical rating scale (NRS) of global health status (r>0.20) at all time points. Reliability, responsiveness, acceptability, and feasibility were tested.RESULTS: One hundred and fifty-two women responded to the 22-item questionnaire pre-delivery (complete in 146), 100 at 24 h, and 10 at 25 h. The ObsQoR-11 correlated with the global health status NRS (r=0.53; 95% confidence interval: 0.43-0.62; P<0.0001) and discriminated good vs poor recovery (NRS score ≥70 vs <70 mm) at 24 h. There was a negative correlation between the ObsQoR-11 score at 24 h and hospital length of stay (r=-0.39; P=0.003). ObsQoR-11 was reliable (internal consistency: 0.85; split-half 0.76; test-retest intra-class correlation coefficient ri>0.6 in 82% of items) and responsive (Cohen effect size: 1.36; standardised response mean: 0.85). A longer 22-item ObsQoR had high (97%) completion rates and short (median: 2 min) completion times.CONCLUSIONS: The ObsQoR-11 provides a valid, reliable, and responsive global assessment of recovery after elective Caesarean delivery.

    View details for PubMedID 30579408

  • Evaluation of Opioid Use With Split Doses of Oral Opioids in a Postcesarean Delivery Analgesia Order Set. Obstetrics and gynecology Nanji, J. A., Guo, N. n., Riley, E. T., Faulkner, B. n., Do, C. n., Carvalho, B. n. 2019

    Abstract

    To evaluate whether an order set change that halved the initial dose of oxycodone and allowed the remainder to be given 1 hour later, if requested, was associated with reduced opioid use and side effects after cesarean delivery.This retrospective, clinical practice study reviewed electronic medical records after implementation of a new order set for cesarean delivery. Oxycodone orders changed from 5 mg (for verbal pain score of 4/10 or lower) and 10 mg (for 5-10/10) to 2.5 mg (for verbal pain score 1-4/10) or 5 mg (for 5-10/10), and the patient requesting pain relief, with a nurse check within 1 hour to administer another 2.5 or 5 mg, respectively, if needed. The primary outcome was opioid use (in intravenous morphine equivalents) in the first 48 hours. Secondary outcomes included incidence and treatment of nausea or vomiting and pruritis, average and peak verbal pain scores within 48 hours, and satisfaction.The records of 1,050 women were examined (542 before and 508 after the change). Opioid use in the first 48 hours was lower after the practice change (median [interquartile range] 10.0 [1.3-25.0] mg before vs 4.4 [0-12.5] mg after; P<.001). A small increase in average verbal pain score occurred (mean [SD] 1.8 [1.0] before vs 2.0 [1.3] after; difference -0.2; 95% CI -0.3 to -0.04). Peak verbal pain score (5.9 [2.0] before vs 6.0 [2.1] after; difference -0.1; 95% CI -0.4 to 0.1) and mean (SD) satisfaction score (97.7 [7.2] before vs 97.1 [7.5] after; difference 0.6, 95% CI -0.5 to 1.6) did not change. Fewer patients reported postoperative nausea or vomiting (30.9% before vs 19.3% after; odds ratio 0.5; 95% CI 0.4 to 0.7).Split doses of oxycodone were associated with 56% reduction in 48 hours opioid use after cesarean delivery.

    View details for DOI 10.1097/AOG.0000000000003305

    View details for PubMedID 31188314

  • Labor Epidural Analgesia to Cesarean Section Anesthetic Conversion Failure: A National Survey ANESTHESIOLOGY RESEARCH AND PRACTICE Desai, N., Gardner, A., Carvalho, B. 2019
  • Alternative Magnesium Sulfate Dosing Regimens for Women With Preeclampsia: A Population Pharmacokinetic Exposure-Response Modeling and Simulation Study. Journal of clinical pharmacology Du, L. n., Wenning, L. A., Carvalho, B. n., Duley, L. n., Brookfield, K. F., Witjes, H. n., de Greef, R. n., Lumbiganon, P. n., Titapant, V. n., Kongwattanakul, K. n., Long, Q. n., Sangkomkamhang, U. S., Gülmezoglu, A. M., Oladapo, O. T. 2019

    Abstract

    Magnesium sulfate is the anticonvulsant of choice for eclampsia prophylaxis and treatment; however, the recommended dosing regimens are costly and cumbersome and can be administered only by skilled health professionals. The objectives of this study were to develop a robust exposure-response model for the relationship between serum magnesium exposure and eclampsia using data from large studies of women with preeclampsia who received magnesium sulfate, and to predict eclampsia probabilities for standard and alternative (shorter treatment duration and/or fewer intramuscular injections) regimens. Exposure-response modeling and simulation were applied to existing data. A total of 10 280 women with preeclampsia who received magnesium sulfate or placebo were evaluated. An existing population pharmacokinetic model was used to estimate individual serum magnesium exposure. Logistic regression was applied to quantify the serum magnesium area under the curve-eclampsia rate relationship. Our exposure-response model-estimated eclampsia rates were comparable to observed rates. Several alternative regimens predicted magnesium peak concentration < 3.5 mmol/L (empiric safety threshold) and eclampsia rate ≤ 0.7% (observed response threshold), including 4 g intravenously plus 10 g intramuscularly followed by either 8 g intramuscularly every 6 hours × 3 doses or 10 g intramuscularly every 8 hours × 2 doses and 10 g intramuscularly every 8 hours × 3 doses. Several alternative magnesium sulfate regimens with comparable model-predicted efficacy and safety were identified that merit evaluation in confirmatory clinical trials.

    View details for DOI 10.1002/jcph.1448

    View details for PubMedID 31157410

  • Transnasal Humidified Rapid-Insufflation Ventilatory Exchange for Elective Laryngeal Surgery During Pregnancy: A Case Report. A&A practice Kowalczyk, J. J., Carvalho, B. n., Collins, J. n. 2019

    Abstract

    Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) maintains oxygenation and blunts the partial pressure of carbon dioxide (PaCO2) rise in nonpregnant subjects during apnea. Physiologic changes of pregnancy may attenuate the utility of THRIVE. We present a nulliparous patient at 31 weeks' gestation undergoing tracheal dilation requiring general anesthesia without intubation utilizing THRIVE. Our data confirms prior reports in nonpregnant patients showing markedly extended time to desaturation. However, PaCO2 rise more closely mirrors classic apneic oxygenation in nonobstetric patients. The PaCO2 elevation and subsequent acidosis may limit the utility of THRIVE for prolonged apnea in pregnant surgical patients.

    View details for DOI 10.1213/XAA.0000000000001098

    View details for PubMedID 31592829

  • In vitro intravenous fluid co-load rates with and without an intravenous fluid warming device. International journal of obstetric anesthesia Kowalczyk, J. J., Yurashevich, M., Austin, N., Carvalho, B. 2018

    View details for PubMedID 30683571

  • A Systematic Review Evaluating Neuraxial Morphine and Diamorphine-Associated Respiratory Depression After Cesarean Delivery ANESTHESIA AND ANALGESIA Sharawi, N., Carvalho, B., Habib, A. S., Blake, L., Mhyre, J. M., Sultan, P. 2018; 127 (6): 1385–95

    Abstract

    The prevalence of neuraxial opioid-induced clinically significant respiratory depression (CSRD) after cesarean delivery is unknown. We sought to review reported cases of author-reported respiratory depression (ARD) to calculate CSRD prevalence. A 6-database literature search was performed to identify ARD secondary to neuraxial morphine or diamorphine, in parturients undergoing cesarean delivery. "Highest" (definite and probable/possible) and "lowest" (definite) prevalences of CSRD were calculated. Secondary outcomes included: (1) prevalence of CSRD associated with contemporary doses of neuraxial opioid, (2) prevalence of ARD as defined by each study's own criteria, (3) case reports of ARD, and (4) reports of ARD reported by the Anesthesia Closed Claims Project database between 1990 and 2016. We identified 78 articles with 18,455 parturients receiving neuraxial morphine or diamorphine for cesarean delivery. The highest and lowest prevalences of CSRD with all doses of neuraxial opioids were 8.67 per 10,000 (95% CI, 4.20-15.16) and 5.96 per 10,000 (95% CI, 2.23-11.28), respectively. The highest and lowest prevalences of CSRD with the use of clinically relevant doses of neuraxial morphine ranged between 1.63 per 10,000 (95% CI, 0.62-8.77) and 1.08 per 10,000 (95% CI, 0.24-7.22), respectively. The prevalence of ARD as defined by each individual paper was 61 per 10,000 (95% CI, 51-74). One published case report of ARD met our inclusion criteria, and there were no cases of ARD from the Closed Claims database analysis. These results indicate that the prevalence of CSRD due to neuraxial morphine or diamorphine in the obstetric population is low.

    View details for PubMedID 30004934

  • Population Pharmacokinetic Modeling to Evaluate Standard Magnesium Sulfate Treatments and Alternative Dosing Regimens for Women With Preeclampsia. Journal of clinical pharmacology Du, L., Wenning, L., Migoya, E., Xu, Y., Carvalho, B., Brookfield, K., Witjes, H., de Greef, R., Lumbiganon, P., Sangkomkamhang, U., Titapant, V., Duley, L., Long, Q., Oladapo, O. T. 2018

    Abstract

    Magnesium sulfate is the standard therapy for prevention and treatment of eclampsia. Twostandard dosing regimens require either continuous intravenous infusion or frequent, large-volume intramuscular injections, which may preclude patients from receiving optimal care. This project sought to identify alternative, potentially more convenient, but similarly effective dosing regimens that could be used in restrictive clinical settings. A 2-compartment population pharmacokinetic (PK) model was developed to characterize serial PK data from 92pregnant women with preeclampsia who received magnesium sulfate. Body weight and serum creatinine concentration had a significant impact on magnesium PK. The final PK model was used to simulate magnesium concentration profiles for the 2standard regimens and several simplified alternative dosing regimens. The simulations suggest that intravenous regimens with loading doses of 8 g over 60 minutes followed by 2 g/h for 10 hours and 12 g over 120 minutes followed by 2 g/h for 8 hours (same total dose as the standard intravenous regimen but shorter treatment duration) would result in magnesium concentrations below the toxic range. For the intramuscular regimens, higher maintenance doses given less frequently (4 g intravenously + 10-g intramuscular loading doses with maintenance doses of 8 g every 6hours or 10 g every 8 hours for 24 hours) or removal of the intravenous loading dose (eg, 10 g intramusculary every 8 hours for 24 hours) may be reasonable alternatives. In addition, individualized dose adjustments based on body weight and serum creatinine were proposed for the standard regimens.

    View details for PubMedID 30422321

  • Correlation of changes in hemodynamic response as measured by cerebral optical spectrometry with subjective pain ratings in volunteers and patients: a prospective cohort study. Journal of pain research Eisenried, A., Austin, N., Cobb, B., Akhbardeh, A., Carvalho, B., Yeomans, D. C., Tzabazis, A. Z. 2018; 11: 1991-1998

    Abstract

    Noninvasive cerebral optical spectrometry is a promising candidate technology for the objective assessment physiological changes during pain perception. This study's primary objective was to test if there was a significant correlation between the changes in physiological parameters as measured by a cerebral optical spectrometry-based algorithm (real-time objective pain assessment [ROPA]) and subjective pain ratings obtained from volunteers and laboring women. Secondary aims were performance assessment using linear regression and receiver operating curve (ROC) analysis.Prospective cohort study performed in Human Pain Laboratory and Labor and Delivery Unit. After institutional review board approval, we evaluated ROPA in volunteers undergoing the cold pressor test and in laboring women before and after epidural or combined spinal epidural placement. Linear regression was performed to measure correlations. ROCs and corresponding areas under the ROCs (AUC), as well as Youden's indices, as a measure of diagnostic effectiveness, were calculated.Correlations between numeric rating scale or visual analog scale and ROPA were significant for both volunteers and laboring women. AUCs for both volunteers and laboring women with numeric rating scale and visual analog scale subjective pain ratings as ground truth revealed at least good (AUC: 70%-79%) to excellent (AUC >90%) distinction between clinically meaningful pain severity differentiations (no/mild-moderate-severe).Cerebral Optical Spectrometry-based ROPA significantly correlated with subjectively reported pain in volunteers and laboring women, and could be a useful monitor for clinical circumstances where direct assessment is not available, or to complement patient-reported pain scores.

    View details for DOI 10.2147/JPR.S162839

    View details for PubMedID 30288094

    View details for PubMedCentralID PMC6162992

  • Prediction of outliers in pain, analgesia requirement, and recovery of function after childbirth: a prospective observational cohort study. British journal of anaesthesia Komatsu, R., Carvalho, B., Flood, P. 2018; 121 (2): 417–26

    Abstract

    BACKGROUND: Prediction models to identify parturients who experience protracted pain, prolonged opioid use, and delayed self-assessed functional recovery are currently inadequate.METHODS: For this study, 213 nulliparous women who planned vaginal delivery were enrolled and assessed daily until they completed three outcomes: (1) pain resolution; (2) opioid cessation; and (3) self-assessed functional recovery to predelivery level. The primary composite endpoint, 'pain and opioid-free functional recovery' was the time required to reach all three endpoints. The subjects were divided into two categories (the worst (longest time) 20% and remaining 80%) for reaching the primary composite endpoint, and each individual component. Prediction models for prolonged recovery were constructed using multivariate logistic regression with demographic, obstetric, psychological, and health-related quality of life characteristics as candidate predictors.RESULTS: Labour induction (vs spontaneous labour onset) predicted the worst 20% for the primary composite endpoint in the final multivariate model. Labour induction and higher postpartum day 1 numerical rating score for pain were predictors for being in the worst 20% for both functional recovery and pain burden. Labour type, delivery type, Patient-Reported Outcomes Measurement Information System (PROMIS) anxiety score, RAND 36 Item Health Survey 1.0 (SF-36) physical health composite score, and postpartum breastfeeding success were predictive of delayed opioid cessation.CONCLUSIONS: Labour induction and elevated numerical rating score for pain are predictive of poor recovery after childbirth. Further research is necessary to determine whether modification would benefit mothers at risk for poor recovery.

    View details for PubMedID 30032880

  • Does the addition of active body warming to in-line intravenous fluid warming prevent maternal hypothermia during elective caesarean section? A randomised controlled trial INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Sultan, P., Carvalho, B. 2018; 35: 115–16

    View details for PubMedID 29343417

  • A Systematic Review of Postoperative Pain Outcome Measurements Utilised in Regional Anesthesia Randomized Controlled Trials. Anesthesiology research and practice Pushpanathan, E., Setty, T., Carvalho, B., Sultan, P. 2018; 2018: 9050239

    Abstract

    Regional anesthesia is a rapidly growing subspecialty. There are few published meta-analyses exploring pain outcome measures utilised in regional anesthesia randomized controlled trials (RCTs), which may be due to heterogeneity in outcomes assessed. This systematic review explores postoperative pain outcomes utilised in regional anesthesia RCTs.A literature search was performed using three databases (Medline, Embase, and CINAHL). Regional anesthesia RCTs with postoperative pain as a primary outcome were included if written in English and published in one of the top 20 impact factor journals between 2005 and 2017. Study quality was assessed using the Cochrane Collaboration's tool for assessing risk of bias.From the 31 included articles, 15 different outcome measures in total were used to assess postoperative pain. The most commonly (16/31) used outcome measures were verbal numerical grading of pain out of 10, total opioid consumption, and visual analogue scale 10 cm (VAS). The need for analgesia was used as an outcome measure where studies did not use a pain rating score. Ten studies reported pain scores on activity and 27/31 studies utilised ≥2 pain outcomes. Time of measurement of pain score also varied with a total of 51 different time points used in total.Analysis of the articles demonstrated heterogeneity and inconsistency in choice of pain outcome and time of measurement within regional anesthesia studies. Identification of these pain outcomes utilised can help to create a definitive list of core outcomes, which may guide future researchers when designing such studies.

    View details for DOI 10.1155/2018/9050239

    View details for PubMedID 30151005

    View details for PubMedCentralID PMC6087609

  • Observational Study Using Ultrasound to Assess Midline Labor Epidural Analgesia Placement and Analgesic Efficacy JOURNAL OF ULTRASOUND IN MEDICINE Weiniger, C. F., Cobb, B., Wang, R. R., Carvalho, B. 2018; 37 (7): 1693–99

    View details for DOI 10.1002/jum.14517

    View details for Web of Science ID 000439934800014

  • Observational Study Using Ultrasound to Assess Midline Labor Epidural Analgesia Placement and Analgesic Efficacy. Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine Weiniger, C. F., Cobb, B., Wang, R. R., Carvalho, B. 2018; 37 (7): 1693-1699

    Abstract

    Labor epidural analgesia failure may relate to nonmidline placement of epidural catheters. We hypothesized that greater deviations of the epidural catheter insertion point from the ultrasound (US)-determined midline would be associated with less effective labor analgesia.A prospective ethically approved cohort study was conducted. Fifty-two healthy average-sized women receiving labor epidural analgesia, inserted by the landmark technique, were approached after delivery. Immediately after removing the epidural catheter, we determined the epidural space midline using US and compared it to the epidural catheter insertion point and to the patient-identified midline (assessed by a pinprick in 1-mm increments). Correlations between the US midline-to-catheter insertion point distance and additional epidural local anesthetic requirements (primary outcome), pain verbal numeric rating scale scores (0-10) 1 hour after epidural insertion, and maternal satisfaction with analgesia were determined. The differences in distances were assessed by a Bland-Altman analysis.There were no significant correlations between the US midline-to-epidural catheter insertion point distance and additional epidural local anesthetic requirements (R2  = 0.138; P = .33), pain verbal numeric rating scale scores 1 hour after the epidural (R2  = 0.121; P = .40) or maternal satisfaction (R2  = 0.085; P = .57). The Bland-Altman analysis revealed that the mean ± SD US midline-to-epidural catheter insertion point distance and patient-identified midline distances were 0.38 ± 0.31 and 0.35 ± 0.46 cm, respectively.In our laboring population, the hypothesis that nonmidline epidural insertion is associated with less-effective labor analgesia was not confirmed in this study cohort. We found minimal differences in distances between the US midline to epidural catheter insertion point and US midline to patient-identified midline.

    View details for DOI 10.1002/jum.14517

    View details for PubMedID 29274080

  • The Accuracy of a Handheld Ultrasound Device for Neuraxial Depth and Landmark Assessment: A Prospective Cohort Trial ANESTHESIA AND ANALGESIA Seligman, K. M., Weiniger, C. F., Carvalho, B. 2018; 126 (6): 1995–98

    Abstract

    This study investigated the accuracy of a wireless handheld ultrasound with pattern recognition software that recognizes lumbar spine bony landmarks and measures depth to epidural space (Accuro, Rivanna Medical, Charlottesville, VA) (AU). AU measurements to epidural space were compared to Tuohy needle depth to epidural space (depth to loss of resistance at epidural placement). Data from 47 women requesting labor epidural analgesia were analyzed. The mean difference between depth to epidural space measured by AU versus needle depth was -0.61 cm (95% confidence interval, -0.79 to -0.44), with a standard deviation of 0.58 (95% confidence interval, 0.48-0.73). Using the AU-identified insertion point resulted in successful epidural placement at first attempt in 87% of patients, 78% without redirects.

    View details for PubMedID 28858898

  • Assessing the Association Between Blood Loss and Postoperative Hemoglobin After Cesarean Delivery: A Prospective Study of 4 Blood Loss Measurement Modalities. Anesthesia and analgesia Fedoruk, K., Seligman, K. M., Carvalho, B., Butwick, A. J. 2018

    Abstract

    BACKGROUND: Visual estimation and gravimetric methods are commonly used to quantify the volume of blood loss during cesarean delivery (CD). However, the correlation between blood loss and post-CD hemoglobin (Hb) is poorly studied, and it is unclear whether the correlation varies according to how blood loss is measured.METHODS: After obtaining Institutional Review Board approval, we performed a prospective study of 61 women undergoing CD to assess the relations between post-CD Hb and blood loss measured using 4 modalities: gravimetric blood loss measurement (gBL), visual blood loss estimation by a blinded obstetrician (oBL) and anesthesiologist (aBL), and the Triton System (tBL). Hb was measured preoperatively and within 10 minutes after CD. gBL was quantified as blood volume in a suction canister in addition to the weight of blood-soaked sponges. tBL was measured with the Triton System by photographing blood-soaked sponges and suction canister contents. To assess the relation between blood loss and post-CD Hb, we performed correlation analyses and compared the magnitude of the correlations across the 4 measurement modalities using William t test. A Bonferroni correction was set to identify a statistically significant correlation (P < .0125) and statistically significant differences between correlation coefficients (P < .008).RESULTS: The mean (standard deviation) preoperative Hb was 12 (1.1) g/dL and post-CD Hb was 11.3 (1.0) g/dL. Median (interquartile range) values for gBL, oBL, aBL, and tBL were 672 mL (266-970), 700 mL (600-800), 750 mL (600-1000), and 496 mL (374-729), respectively. A statistically significant but weak correlation was observed between tBL and post-CD Hb (r = -0.33; P = .01). No statistically significant correlations were observed among aBL (r = -0.25; P = .06), oBL (r = -0.2; P = .13), and gBL (r = -0.3; P = .03) with post-CD Hb. We did not detect any significant differences between any 2 correlation coefficients across the 4 modalities.CONCLUSIONS: Given that we observed only weak correlations between each modality with post-CD Hb and no significant differences in the magnitude of the correlations across the 4 modalities, there may be limited clinical utility in estimating post-CD Hb from blood loss values measured with any of the 4 modalities.

    View details for PubMedID 29847380

  • Left Uterine Tilt for Cesarean Delivery Significantly Improves Maternal Hemodynamics and Should Not Be Considered Outdated Dogma ANESTHESIOLOGY Riley, E. T., Dyer, R. A., Carvalho, B. 2018; 128 (4): 858–59

    View details for PubMedID 29533299

  • EFFICACY OF PATIENT CHOICE OF DIFFERENT POSTOPERATIVE ANALGESIC PROTOCOLS AFTER CESAREAN DELIVERY: A RANDOMIZED PROSPECTIVE CLINICAL TRIAL Kowalczyk, J. J., Sutton, C. D., Flood, P., Carvalho, B. LIPPINCOTT WILLIAMS & WILKINS. 2018: 412
  • ASSESSMENT OF MATERNAL PERIPHERAL IMMUNE SYSTEM BY MASS CYTOMETRY TO PREDICT THE ONSET OF LABOR Ando, K., Han, X., Ghaemi, S., Angst, M., Carvalho, B., Aghaeepour, N., Gaudilliere, B. LIPPINCOTT WILLIAMS & WILKINS. 2018: 403
  • Mass Cytometry and Proteomic Based Prediction of the Onset of Labor. Ando, K., Han, X., Ghaemi, S., Tsai, A., Ganio, E., Gaudilliere, D., Culos, T., Shaw, G., Wong, R., Stevenson, D., Carvalho, B., Tingle, M., Angst, M., Aghaeepor, N., Gaudilliere, B., Stanford March Dimes Prematurity SAGE PUBLICATIONS INC. 2018: 153A
  • High-dose versus low-dose local anaesthetic for transversus abdominis plane block post-Caesarean delivery analgesia: a meta-analysis BRITISH JOURNAL OF ANAESTHESIA Ng, S. C., Habib, A. S., Sodha, S., Carvalho, B., Sultan, P. 2018; 120 (2): 252–63

    Abstract

    The optimal local-anaesthetic (LA) dose for transversus-abdominis-plane (TAP) block is unclear. In this meta-analysis, we aimed to determine whether TAP blocks for Caesarean delivery (CD) with low-dose (LD) LA demonstrated non-inferiority in terms of analgesic efficacy, compared with high-dose (HD) LA.A literature search was performed for randomised controlled trials examining the analgesic efficacy of TAP blocks vs control after CD. The different dosing used in these studies was classified as HD or LD (bupivacaine equivalents >50 or ≤50 mg per block side, respectively). The pooled results of each dose group vs control were indirectly compared using the Q test. The primary outcome was 24 h opioid consumption. Secondary outcomes included 6 and 24 h postoperative pain scores, time to first analgesia, 6 h opioid consumption, opioid-related side-effects, and maternal satisfaction.Fourteen studies consisting of 770 women (389 TAP and 381 control) were included. Compared with controls, the 24 h opioid consumption (milligram morphine equivalents) was lower in HD [mean difference (MD) 95% confidence interval (CI) -22.41 (-38.56, -6.26); P=0.007; I2=93%] and LD [MD 95% CI -16.29 (-29.74, -2.84); P=0.02; I2=98%] TAP groups. However, no differences were demonstrated between the HD and LD groups (P=0.57). There were also no differences between the HD and LD groups for the 6 h opioid consumption, time to first analgesia, 6 and 24 h pain scores, postoperative nausea and vomiting, pruritus, and maternal satisfaction.Low-dose TAP blocks for Caesarean delivery provide analgesia and opioid-sparing effects comparable with the high-dose blocks. This suggests that lower doses can be used to reduce local anaesthetic toxicity risk without compromising the analgesic efficacy.

    View details for PubMedID 29406174

  • The Effect of Glycopyrrolate on the Incidence of Hypotension and Vasopressor Requirement During Spinal Anesthesia for Cesarean Delivery: A Meta-analysis ANESTHESIA AND ANALGESIA Patel, S. D., Habib, A. S., Phillips, S., Carvalho, B., Sultan, P. 2018; 126 (2): 552–58

    Abstract

    The objective of this meta-analysis was to determine the efficacy of glycopyrrolate at reducing spinal hypotension during cesarean delivery.A literature search was performed to identify randomized controlled trials investigating the effect of glycopyrrolate on spinal-induced hypotension during cesarean delivery. Primary outcomes were intraoperative hypotension and vasopressor requirement (phenylephrine equivalents). Secondary outcomes included heart rate (HR), nausea and vomiting, dry mouth, and Apgar scores. Risk ratios (RRs), and mean differences (MDs) were calculated using random-effects modeling with 95% confidence intervals for primary outcomes and 99% confidence intervals for secondary outcomes.Five randomized controlled trials met our inclusion criteria. A total of 311 patients were included: 153 received glycopyrrolate and 158 placebo. The incidence of spinal-induced hypotension was no different with prophylactic glycopyrrolate compared to control (RR, 0.93 [0.71-1.21]; P = .59), but the total phenylephrine dose required was significantly reduced with glycopyrrolate (MD, -62.64 μg [-107.61 to -17.66 μg]; P = .006). The maximal HR achieved in the glycopyrrolate group was significantly higher compared to controls (MD, 15.85 bpm [5.40-26.31]; P < .0001); however, the incidence of bradycardia was not statistically different. The incidence of intraoperative nausea and vomiting was not different between groups; however, glycopyrrolate increased the risk of dry mouth (RR, 5.15 [1.82-14.57]; P < .0001). Apgar scores at 1 and 5 minutes did not differ between groups.Prophylactic glycopyrrolate does not reduce the incidence of spinal-induced hypotension but results in a modest reduction in vasopressor requirements while increasing maternal HR.

    View details for PubMedID 28704246

  • International consensus statement on the management of hypotension with vasopressors during caesarean section under spinal anaesthesia ANAESTHESIA Kinsella, S. M., Carvalho, B., Dyer, R. A., Fernando, R., McDonnell, N., Mercier, F. J., Palanisamy, A., Sia, A. H., Van de Velde, M., Vercueil, A. 2018; 73 (1): 71–92

    View details for PubMedID 29090733

  • Correlation of changes in hemodynamic response as measured by cerebral optical spectrometry with subjective pain ratings in volunteers and patients: a prospective cohort study JOURNAL OF PAIN RESEARCH Eisenried, A., Austin, N., Cobb, B., Akhbardeh, A., Carvalho, B., Yeomans, D. C., Tzabazis, A. Z. 2018; 11: 1991–98
  • A Systematic Review of Postoperative Pain Outcome Measurements Utilised in Regional Anesthesia Randomized Controlled Trials ANESTHESIOLOGY RESEARCH AND PRACTICE Pushpanathan, E., Setty, T., Carvalho, B., Sultan, P. 2018
  • Cost-benefit Analysis of Maintaining a Fully Stocked Malignant Hyperthermia Cart versus an Initial Dantrolene Treatment Dose for Maternity Units. Anesthesiology Ho, P. T., Carvalho, B. n., Sun, E. C., Macario, A. n., Riley, E. T. 2018

    Abstract

    The Malignant Hyperthermia Association of the United States recommends that dantrolene be available for administration within 10 min. One approach to dantrolene availability is a malignant hyperthermia cart, stocked with dantrolene, other drugs, and supplies. However, this may not be of cost benefit for maternity units, where triggering agents are rarely used.The authors performed a cost-benefit analysis of maintaining a malignant hyperthermia cart versus a malignant hyperthermia cart readily available within the hospital versus an initial dantrolene dose of 250 mg, on every maternity unit in the United States. A decision-tree model was used to estimate the expected number of lives saved, and this benefit was compared against the expected costs of the policy.We found that maintaining a malignant hyperthermia cart in every maternity unit in the United States would reduce morbidity and mortality costs by $3,304,641 per year nationally but would cost $5,927,040 annually. Sensitivity analyses showed that our results were largely driven by the extremely low incidence of general anesthesia. If cesarean delivery rates in the United States remained at 32% of all births, the general anesthetic rate would have to be greater than 11% to achieve cost benefit. The only cost-effective strategy is to keep a 250-mg dose of dantrolene on the unit for starting therapy.It is not of cost benefit to maintain a fully stocked malignant hyperthermia cart with a full supply of dantrolene within 10 min of maternity units. We recommend that hospitals institute alternative strategies (e.g., maintain a small supply of dantrolene on the maternity unit for starting treatment).

    View details for PubMedID 29672336

  • Preoperative anterior thigh temperature does not correlate with perioperative temporal hypothermia during cesarean delivery with spinal anesthesia: Secondary analysis of a randomized control trial. International journal of obstetric anesthesia Cobb, B. n., Abir, G. n., Carvalho, B. n. 2018; 33: 40–45

    Abstract

    Core-to-peripheral redistribution of heat, secondary to sympathetic-mediated vasodilation, is the major mechanism leading to early perioperative hypothermia after neuraxial anesthesia. The study aim was to determine if preoperative anterior thigh (peripheral lower extremity) temperature predicted perioperative temporal (core) temperature decrease during cesarean delivery with spinal anesthesia.Secondary analysis of data derived from a prospective, randomized study of 46 healthy women undergoing scheduled cesarean delivery with spinal anesthesia was performed. Anterior thigh temperature was measured preoperatively prior to spinal anesthesia. The primary outcome was maximum perioperative temporal temperature decrease. Secondary outcomes included incidence of temporal hypothermia (temperature <36°C), shivering, and thermal comfort scores. This study ran concurrently with a previously published trial comparing no active intraoperative warming with active warming.There was no correlation between preoperative anterior thigh temperature and maximum perioperative temporal temperature decrease (r=-0.049, P=0.751). The mean±standard deviation preoperative anterior thigh temperature of women who developed temporal hypothermia compared to those who did not was 32.4±0.8°C versus 32.4±0.70°C respectively (P=0.995). Preoperative anterior thigh temperature did not correlate with the incidence of shivering (r=0.267, P=0.080) or thermal comfort scores (r=0.233, P=0.129).Preoperative anterior thigh temperature does not correlate with the degree of perioperative temporal temperature decrease, likelihood of developing hypothermia, shivering, or thermal comfort during cesarean delivery with spinal anesthesia. Although core-to-peripheral redistribution of heat after neuraxial anesthesia is a major mechanism of perioperative heat loss, a lower extremity temperature prediction hypothesis was not confirmed in this population.

    View details for PubMedID 29017742

  • Similarities between obstetric anesthesia and the service industry reply INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Sutton, C., Carvalho, B. 2017; 32: 93–94

    View details for PubMedID 28801161

  • Recovery after Nulliparous Birth A Detailed Analysis of Pain Analgesia and Recovery of Function ANESTHESIOLOGY Komatsu, R., Carvalho, B., Flood, P. D. 2017; 127 (4): 684–94

    Abstract

    The majority of parturients in the United States first return for evaluation by their obstetric practitioner 6 weeks after delivery. As such, there is little granular data on the pain experience, analgesic requirements, and functional recovery during the postpartum period. This prospective observational study was performed to evaluate these factors to provide expectations for patients.A total of 213 nulliparous women were enrolled and assessed daily until they completed 3 outcomes: (1) pain resolution; (2) opioid cessation; and (3) self-assessed functional recovery from delivery. The primary endpoint, pain- and opioid-free functional recovery, was the time required to reach all three of the endpoints. Pain burden was assessed as the area under the curve created by plotting the daily numerical pain rating scale against the days required to attain pain resolution. Times to attain study endpoints after cesarean delivery and vaginal delivery were compared using survival analysis.After vaginal delivery, days required for pain and opioid-free functional recovery (median [interquartile range (IQR)]) were 19 [11 to 26], for opioid cessation 0 [0 to 2], termination of all analgesic (including nonsteroidal antiinflammatories and acetaminophen) 11 [5 to 17], and pain resolution 14 [7 to 24]. Achievement of these endpoints after cesarean delivery required 27 [19 to 40], 9 [5 to 12], 16 [11 to 24], and 21 [14 to 27] days, respectively.There is clinically significant variability between healthy nulliparous parturients in the pain experience, opioid use, and functional recovery after childbirth following vaginal and cesarean delivery. Recovery to predelivery function is similar after vaginal and cesarean delivery, and approximately half of the variance was explained by pain burden.

    View details for PubMedID 28926443

    View details for PubMedCentralID PMC5657561

  • Ambient operating room temperature: mother, baby or surgeon? British journal of anaesthesia Sultan, P., Habib, A. S., Carvalho, B. 2017; 119 (4): 839

    View details for DOI 10.1093/bja/aex307

    View details for PubMedID 29121314

  • Optimising triggers for patient-assisted remifentanil analgesia during labour. Anaesthesia Weiniger, C. F., Carvalho, B., Landau-Cahana, R. 2017; 72 (9): 1155-1156

    View details for DOI 10.1111/anae.14015

    View details for PubMedID 28804880

  • In Response. Anesthesia and analgesia Weiniger, C. F., Carvalho, B., Einav, S. 2017; 125 (2): 696-697

    View details for DOI 10.1213/ANE.0000000000002209

    View details for PubMedID 28632530

  • A Perspective on Hypercapnia Events After Cesarean Delivery in Women Receiving Intrathecal Morphine. Anesthesia and analgesia Carvalho, B., Weiniger, C. F. 2017; 125 (1): 355-356

    View details for DOI 10.1213/ANE.0000000000002146

    View details for PubMedID 28614130

  • Optimization of Maternal Magnesium Sulfate Administration for Fetal Neuroprotection: Application of a Prospectively Constructed Pharmacokinetic Model to the BEAM Cohort. Journal of clinical pharmacology Brookfield, K. F., Elkomy, M., Su, F., Drover, D. R., Carvalho, B. 2017

    Abstract

    The aim of the study was to identify the optimal therapeutic maternal magnesium drug exposure and maternal serum concentration to prevent cerebral palsy in the extremely preterm fetus. We applied a previously constructed pharmacokinetic model adjusted for indication to a large cohort of pregnant women receiving magnesium sulfate to prevent cerebral palsy in their preterm offspring at 20 different US academic centers between December 1997 and May 2004. We simulated the population-based individual maternal serum magnesium concentration at the time of delivery and the total magnesium dose for each woman who received magnesium sulfate to determine the relationship between maternal serum magnesium level at the time of delivery and the development of cerebral palsy. Among 1905 women who met inclusion criteria, the incidence of cerebral palsy in the cohort was 3.6% for women who had received magnesium sulfate and 6.4% for controls. The simulated maternal serum concentration at delivery associated with the lowest probability of delivering an infant with cerebral palsy was 4.1 mg/dL (95%CI 3.7 to 4.4). Our population-based estimates of magnesium disposition suggest that to optimize fetal neuroprotection and prevent cerebral palsy, magnesium sulfate administration should target a maternal serum magnesium level between 3.7 and 4.4 mg/dL at delivery.

    View details for DOI 10.1002/jcph.941

    View details for PubMedID 28589614

  • General anaesthesia for caesarean section: is the end in sight for thiopental? British journal of hospital medicine (London, England : 2005) Desai, N., Carvalho, B. 2017; 78 (6): 358

    View details for DOI 10.12968/hmed.2017.78.6.358

    View details for PubMedID 28614017

  • Patient choice compared with no choice of intrathecal morphine dose for caesarean analgesia: a randomized clinical trial. British journal of anaesthesia Carvalho, B., Mirza, F., Flood, P. 2017; 118 (5): 762-771

    Abstract

    The study aimed to determine whether a patient's choice for their intrathecal morphine (ITM) dose reflects their opioid requirements and pain after caesarean delivery and if giving women a choice of ITM dose would reduce opioid use and improve pain scores compared with women who did not have a choice.A total of 120 women undergoing caesarean delivery with spinal anaesthesia were enrolled in this randomized, double-blind study. Patients were randomly assigned to a choice of 100 or 200 μg ITM or no choice. The study involved deception, such that all participants were still randomly assigned 100 or 200 μg ITM regardless of choice. Rescue opioid use over the 48-h study period was the primary outcome measure. Pain at rest and movement and side effect (pruritus, nausea, and vomiting) data were collected 3, 6, 12, 24, 36 and 48 h postoperatively. Data are presented as median [95% confidence interval (CI)].Women who requested the larger ITM dose required more supplemental opioid [median 0.8 (95% CI 0.4-1.3)] mg morphine equivalents at each assessment interval; P  < 0.001] and reported more pain with movement [median 1.2 (95% CI 0.5-1.9)] verbal numerical rating score of 0-10 points] than patients who requested the smaller ITM dose ( P  = 0.0008), regardless of the ITM dose given. There was no difference in opioid use whether the patient was offered a perceived choice or not.Women who were given a choice and chose the larger ITM dose correctly anticipated a greater postoperative opioid requirement and more pain compared with women who chose the smaller dose. Simply being offered a choice did not impact opioid use or pain scores after caesarean delivery.ClinicalTrials.gov (NCT01425762).

    View details for DOI 10.1093/bja/aex039

    View details for PubMedID 28486595

  • Programmed intermittent epidural boluses for maintenance of labor analgesia: an impact study Reply INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Riley, E. T., McKenzie, C. P., Cobb, B., Carvalho, B. 2017; 30: 76

    View details for PubMedID 28129934

  • What's trending now? An analysis of trends in internet searches for labor epidurals INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Sutton, C. D., Carvalho, B. 2017; 30: 52-57

    Abstract

    The study aim was to investigate internet use for obtaining information about epidurals for labor and delivery.Google Trends for US data was queried from 2004 to 2015 to find the most common searches and determine temporal trends. The Google Trends query used the term [epidural] and evaluated changes in search trends over time. Search comparisons were made for each year from 2004 to 2015, and three equal time epochs during the study period (2004-07, 2008-11, 2012-15) were compared. We also compared searches for epidurals with commonly searched birth-related terms.Internet searches are increasing; there were 726000 searches for [epidural] in 2015. Search terms with the most significant growth in the past 4years (2012-15) were "birth with epidural," "pain after epidural," "labor without epidural," "epidural birth video," and "epidural vs natural". Searches for epidural side effects, risks, and pain on insertion were among the most common and were increasing most rapidly. Searches related to epidurals were more common than searches related to "natural births", "home births", and "labor pain", but were less common than searches for "midwives" or "doulas".The findings provide an insight into internet use by those seeking information about labor analgesic options. Identifying the most common and rapidly increasing online search queries may guide physician-parturient interactions and online content creation, to address labor analgesic topics that most interest users.

    View details for DOI 10.1016/j.ijoa.2017.02.004

    View details for Web of Science ID 000401676500009

    View details for PubMedID 28347574

  • Programmed Intermittent Epidural Boluses (PIEB) for Maintenance of Labor Analgesia: A Superior Technique to Continuous Epidural Infusion? Turkish journal of anaesthesiology and reanimation Riley, E. T., Carvalho, B. 2017; 45 (2): 65-66

    View details for DOI 10.5152/TJAR.2017.09031

    View details for PubMedID 28439433

  • Analysis of Physiological Respiratory Variable Alarm Alerts Among Laboring Women Receiving Remifentanil ANESTHESIA AND ANALGESIA Weiniger, C. F., Carvalho, B., Stocki, D., Einav, S. 2017; 124 (4): 1211-1218
  • Programmed Intermittent Epidural Boluses (PIEB) for Maintenance of Labor Analgesia: An Incremental Step Before the Next Paradigm Shift? Turkish journal of anaesthesiology and reanimation Carvalho, B., Riley, E. T. 2017; 45 (2): 73-75

    View details for DOI 10.5152/TJAR.2017.09034

    View details for PubMedID 28439436

  • Effect of a High-Rate Versus a Low-Rate Oxytocin Infusion for Maintaining Uterine Contractility During Elective Cesarean Delivery: A Prospective Randomized Clinical Trial. Anesthesia and analgesia Duffield, A., McKenzie, C., Carvalho, B., Ramachandran, B., Yin, V., El-Sayed, Y. Y., Riley, E. T., Butwick, A. J. 2017; 124 (3): 857-862

    Abstract

    Oxytocin is routinely used as prophylaxis against uterine atony. During elective cesarean delivery (CD), an oxytocin bolus is used to initiate adequate uterine tone, followed by an oxytocin infusion to maintain uterine contractility. However, it is unclear whether oxytocin maintenance infusion rate influences total estimated blood loss (EBL).We performed a prospective, randomized, double-blind trial in 51 women undergoing elective CD. Women were randomly assigned to receive an oxytocin maintenance infusion of 2.5 or 15 U/h. All women received an oxytocin 1 U bolus to initiate adequate uterine tone. The primary outcome was EBL. EBL values between groups were compared using a Mann-Whitney U test; P < .05 as statistically significant. The median EBL difference with 95% confidence intervals was also calculated. Secondary outcomes included adequacy of uterine tone, use of additional uterotonics, and oxytocin-related side effects, including hypotension.Of 51 women, 24 received a low-rate infusion and 27 received a high-rate infusion. Median (interquartile range) EBL values in the low-rate and high-rate groups were 634 (340-886) mL versus 512 (405-740) mL, respectively (P = .7). The median difference in EBL between groups was 22 mL; 95% confidence interval = -158 to 236 mL. The rate of postpartum hemorrhage did not differ between groups (low-rate group: 4/24 [16.7%] versus high-rate group: 4/26 [15.4%]). There were no between-group differences over time (first 20 minutes after commencing infusion) in the incidence of adequate uterine tone (P = .72) or hypotension (P = .32).Among women undergoing elective CD receiving an oxytocin maintenance infusion, EBL and uterine tone did not differ between women receiving 2.5 U/h oxytocin and those receiving 15 U/h oxytocin. Our findings suggest that efficacy can be obtained with a low oxytocin maintenance infusion rate; however, dose-finding studies are needed to determine the infusion rate that optimizes drug efficacy while minimizing side effects.

    View details for DOI 10.1213/ANE.0000000000001658

    View details for PubMedID 28212181

    View details for PubMedCentralID PMC5319709

  • Optimal Pain Management After Cesarean Delivery. Anesthesiology clinics Sutton, C. D., Carvalho, B. 2017; 35 (1): 107-124

    Abstract

    Cesarean delivery rates are increasing worldwide, and effective postoperative pain management is a key priority of women undergoing cesarean delivery. Inadequate pain management in the acute postoperative period is associated with persistent pain, greater opioid use, delayed functional recovery, and increased postpartum depression. In addition to pain relief, optimal management of patients after cesarean delivery should address the goals of unrestricted maternal mobility, minimal maternal and neonatal side effects, rapid recovery to baseline functionality, and early discharge home. Multimodal analgesia should include neuraxial morphine in conjunction with nonopioid adjuncts, with additional oral or intravenous opioids reserved for severe breakthrough pain.

    View details for DOI 10.1016/j.anclin.2016.09.010

    View details for PubMedID 28131114

  • Postpartum hemorrhage following vaginal delivery: risk factors and maternal outcomes. Journal of perinatology Miller, C. M., Cohn, S., Akdagli, S., Carvalho, B., Blumenfeld, Y. J., Butwick, A. J. 2017; 37 (3): 243-248

    Abstract

    Limited understanding of risk factors exists for postpartum hemorrhage (PPH) post-vaginal delivery. The aim of this study was to identify risk factors for PPH post-vaginal delivery within a contemporary obstetric cohort.Retrospective case-control study. PPH was classified by an estimated blood loss ⩾500 ml. Risk factors for PPH were identified using univariable and multivariable logistic regression. We secondarily investigated maternal outcomes and medical and surgical interventions for PPH management.The study cohort comprised 159 cases and 318 controls. Compared with a second-stage duration <2 h, a second stage⩾3 h was associated with PPH (adjusted odds ratio=2.3; 95% CI=1.2 to 4.6). No other clinical or obstetric variables were identified as independent risk factors for PPH. Among cases, 4% received red blood cells and 1% required intensive care admission.Although PPH-related morbidity may be uncommon after vaginal delivery, PPH should be anticipated for women after a second stage ⩾3 h.

    View details for DOI 10.1038/jp.2016.225

    View details for PubMedID 27977018

    View details for PubMedCentralID PMC5334143

  • Clinical and microbiological features of maternal sepsis: a retrospective study INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Abir, G., Akdagli, S., Butwick, A., Carvalho, B. 2017; 29: 26-33

    Abstract

    Identifying pregnant women with sepsis is challenging because diagnostic clinical and laboratory criteria overlap with normal pregnant physiologic indices. Our primary study aim was to describe clinical and laboratory characteristics of women diagnosed with sepsis, severe sepsis and septic shock. Our secondary aim was to determine positive predictive values for International Classification of Disease (ICD)-9 billing codes for sepsis, severe sepsis, and septic shock.After gaining Institutional Review Board approval, we identified women with ICD-9 codes for sepsis, severe sepsis and septic shock who were admitted to a single tertiary obstetric center from 2007-2013. Diagnoses were confirmed using criteria from the International Sepsis Definitions Conference report. Demographic, obstetric, vital signs and laboratory data were abstracted by medical chart review.We identified 190 women with sepsis-related ICD-9 codes: of these, 35 (18%) women met the criteria for a clinical diagnosis of sepsis, severe sepsis or septic shock. Twenty (57%) women had a sepsis-related diagnosis after cesarean delivery. Twenty-one (60%) women had one or more pre-existing medical conditions and 19 (54%) women had one or more obstetric-related conditions. The genital tract was the most common site of infection. We observed considerable heterogeneity in maternal vital signs and laboratory indices for women with ICD-9 codes for sepsis, severe sepsis, and septic shock. The positive predictive value for each sepsis-related ICD-9 code was low: 16% (95% CI 10 to 24%) for sepsis, 10% (95% CI 3 to 25%) for severe sepsis and 24% (95% CI 10 to 46%) for septic shock.We identified marked heterogeneity in patient characteristics, clinical features, laboratory indices and microbiological findings among cohorts of women diagnosed with maternal sepsis, severe sepsis or septic shock. Based on our findings, the incidence of maternal sepsis using ICD-9 codes may be significantly overestimated.

    View details for DOI 10.1016/j.ijoa.2016.09.003

    View details for Web of Science ID 000394917700006

  • Essentials of Our Current Understanding: Abdominal Wall Blocks. Regional anesthesia and pain medicine Chin, K. J., McDonnell, J. G., Carvalho, B., Sharkey, A., Pawa, A., Gadsden, J. 2017; 42 (2): 133-183

    Abstract

    Abdominal wall blocks rely on the spread of local anesthetic within musculofascial planes to anesthetize multiple small nerves or plexuses, rather than targeting specific nerve structures. Ultrasonography is primarily responsible for the widespread adoption of techniques including transversus abdominis plane and rectus sheath blocks, as well as the introduction of novel techniques such as quadratus lumborum and transversalis fascia blocks. These blocks are technically straightforward and relatively safe and reduce pain and opioid requirements in many clinical settings. The data supporting these outcomes, however, can be inconsistent because of heterogeneity of study design. The extent of sensory blockade is also somewhat variable, because it depends on the achieved spread of local anesthetic and the anatomical course of the nerves being targeted. The blocks mainly provide somatic analgesia and are best used as part of a multimodal analgesic regimen. This review summarizes the anatomical, sonographic, and technical aspects of the abdominal wall blocks in current use, examining the current evidence for the efficacy and safety of each.

    View details for DOI 10.1097/AAP.0000000000000545

    View details for PubMedID 28085788

  • The Society for Obstetric Anesthesia and Perinatology Consensus Statement on the Anesthetic Management of Pregnant and Postpartum Women Receiving Thromboprophylaxis or Higher Dose Anticoagulants. Anesthesia and analgesia Leffert, L. n., Butwick, A. n., Carvalho, B. n., Arendt, K. n., Bates, S. M., Friedman, A. n., Horlocker, T. n., Houle, T. n., Landau, R. n., Dubois, H. n., Fernando, R. n., Houle, T. n., Kopp, S. n., Montgomery, D. n., Pellegrini, J. n., Smiley, R. n., Toledo, P. n. 2017

    Abstract

    Venous thromboembolism is recognized as a leading cause of maternal death in the United States. Thromboprophylaxis has been highlighted as a key preventive measure to reduce venous thromboembolism-related maternal deaths. However, the expanded use of thromboprophylaxis in obstetrics will have a major impact on the use and timing of neuraxial analgesia and anesthesia for women undergoing vaginal or cesarean delivery and other obstetric surgeries. Experts from the Society of Obstetric Anesthesia and Perinatology, the American Society of Regional Anesthesia, and hematology have collaborated to develop this comprehensive, pregnancy-specific consensus statement on neuraxial procedures in obstetric patients receiving thromboprophylaxis or higher dose anticoagulants. To date, none of the existing anesthesia societies' recommendations have weighed the potential risks of neuraxial procedures in the presence of thromboprophylaxis, with the competing risks of general anesthesia with a potentially difficult airway, or maternal or fetal harm from avoidance or delayed neuraxial anesthesia. Furthermore, existing guidelines have not integrated the pharmacokinetics and pharmacodynamics of anticoagulants in the obstetric population.The goal of this consensus statement is to provide a practical guide of how to appropriately identify, prepare, and manage pregnant women receiving thromboprophylaxis or higher dose anticoagulants during the ante-, intra-, and postpartum periods. The tactics to facilitate multidisciplinary communication, evidence-based pharmacokinetic and spinal epidural hematoma data, and Decision Aids should help inform risk-benefit discussions with patients and facilitate shared decision making.

    View details for PubMedID 29099429

  • Nitrous oxide for labor analgesia: Utilization and predictors of conversion to neuraxial analgesia. Journal of clinical anesthesia Sutton, C. D., Butwick, A. J., Riley, E. T., Carvalho, B. n. 2017; 40: 40–45

    Abstract

    We examined the characteristics of women who choose nitrous oxide for labor analgesia and identified factors that predict conversion from nitrous oxide to labor neuraxial analgesia.Retrospective descriptive study.Labor and Delivery Ward.146 pregnant women who used nitrous oxide for analgesia during labor and delivery between September 2014 and September 2015.Chart review only.Demographic, obstetric, and intrapartum characteristics of women using nitrous oxide were examined. Multivariable logistic regression was performed to identify factors associated with conversion from nitrous oxide to neuraxial analgesia. Data are presented as n (%), median [IQR], adjusted relative risk (aRR), and 95% confidence intervals (CI) as appropriate.During the study period, 146 women used nitrous oxide for labor analgesia (accounting for 3% of the total deliveries). The majority (71.9%) of women who used nitrous oxide were nulliparous, and over half (51.9%) had expressed an initial preference for "nonmedical birth." The conversion rate to neuraxial blockade was 63.2%, compared to a concurrent institutional rate of 85.1% in women who did not use nitrous oxide. Factors associated with conversion from nitrous oxide to neuraxial blockade were labor induction (aRR=2.0, CI 1.2-3.3) and labor augmentation (aRR=1.7, CI 1.0-2.9).Only a small number of women opted to use nitrous oxide during labor, analgesia was minimal, and most converted to neuraxial analgesia. Women with induced and augmented labors should be counseled about the increased likelihood that they will convert to neuraxial analgesia.

    View details for PubMedID 28625444

  • Optimal administration of cefazolin prophylaxis for cesarean delivery. Journal of perinatology : official journal of the California Perinatal Association Duffield, A., Sultan, P., Riley, E. T., Carvalho, B. 2017; 37 (1): 16-20

    View details for DOI 10.1038/jp.2016.210

    View details for PubMedID 28050017

  • Comparative Echogenicity of an Epidural Catheter and 2 New Catheters Designed for Ultrasound-Guided Continuous Peripheral Nerve Blocks. Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine Moy, D. M., Kim, T. E., Harrison, T. K., Leng, J. C., Carvalho, B. n., Howard, S. K., Shum, C. n., Kou, A. n., Mariano, E. R. 2017

    Abstract

    Visualization of the catheter during ultrasound-guided continuous nerve block performance may be difficult but is an essential skill for regional anesthesiologists. The objective of this in vitro study was to evaluate 2 newer catheters designed for enhanced echogenicity and compare them to a widely used catheter not purposely designed for ultrasound guidance. Outcomes were the numbers of first-place rankings among all 3 catheters and scores on individual echogenicity criteria as assessed by 2 blinded reviewers. Catheters designed for echogenicity are not superior to an older regional anesthesia catheter, and results suggest that catheter preference for ultrasound-guided placement may be subjective.

    View details for PubMedID 28627724

  • Not Too Little, Not Too Much: Finding the Goldilocks Zone for Spinal Anesthesia to Facilitate External Cephalic Version. Anesthesiology Carvalho, B. n., Bateman, B. T. 2017; 127 (4): 596–98

    View details for PubMedID 28799953

  • Rectus Muscle Reapproximation at Cesarean Delivery and Postoperative Pain: A Randomized Controlled Trial. Surgery journal (New York, N.Y.) Lyell, D. J., Naqvi, M. n., Wong, A. n., Urban, R. n., Carvalho, B. n. 2017; 3 (3): e128–e133

    Abstract

    Objective  Rectus muscle reapproximation at cesarean delivery (CD) is performed frequently by some obstetricians; however, the effect on postoperative pain is unclear. To this end, we investigated whether rectus muscle reapproximation increases postoperative pain. Materials and Methods  This is a prospective, double-blind, randomized controlled trial of women undergoing primary CD with singleton or twin pregnancy at >35 weeks' gestation. Women were randomized to rectus muscle reapproximation with three interrupted sutures or no reapproximation. Exclusion criteria were prior cesarean, prior laparotomy, vertical skin incision, active labor, chronic analgesia use, allergy to opioid or nonsteroidal anti-inflammatory drugs, and body mass index ≥ 40. Intra- and postoperative pain management was standardized within the study protocol. The primary outcome was a combined movement pain and opioid use score averaged over the 72-hour study period, called the Silverman integrated assessment. Movement pain scores were assessed at 24, 48, and 72 postoperative hours. Results  In total, 63 women were randomized, of whom 35 underwent rectus muscle reapproximation and 28 did not. Demographic and obstetric variables were similar between groups. Silverman integrated assessment scores during the 72-hour postoperative period were higher in the rectus muscle reapproximation group (15 ± 100% vs. -31 ± 78% difference from the mean; p  = 0.04). Operative times were similar between groups (63 ± 15 vs. 65 ± 15 minutes; p  = 0.61), and there were no surgical complications in either group. Maternal satisfaction with analgesia at 72 hours was high in both groups (85% [73-90] rectus muscle reapproximation vs. 90% [75-100]; p  = 0.16). Conclusion  Rectus muscle reapproximation increased immediate postoperative pain without differences in operative time, surgical complications, or maternal satisfaction. Benefits of rectus muscle reapproximation should be weighed against increased postoperative pain, and analgesia should be planned accordingly.

    View details for PubMedID 28840194

    View details for PubMedCentralID PMC5565698

  • Comparative Effectiveness of Lower Leg Compression Devices Versus Sequential Compression Devices to Prevent Postspinal Hypotension During Cesarean Delivery. Anesthesia and analgesia Carvalho, B. n., Zheng, L. L., Butwick, A. n. 2017; 124 (2): 696–97

    View details for PubMedID 28098691

  • Postcesarean delivery analgesia. Best practice & research. Clinical anaesthesiology Carvalho, B. n., Butwick, A. J. 2017; 31 (1): 69–79

    Abstract

    Effective pain management should be a key priority in women undergoing cesarean delivery. Suboptimal perioperative pain management is associated with chronic pain, greater opioid use, delayed functional recovery, impaired maternal-fetal bonding, and increased postpartum depression. Severe acute postoperative pain is also strongly associated with persistent pain after cesarean delivery. Multimodal analgesia is the core principle for cesarean delivery pain management. The use of neuraxial morphine and opioid-sparing adjuncts such as scheduled nonsteroidal anti-inflammatory medications and acetaminophen is recommended for all women undergoing cesarean delivery with neuraxial anesthesia unless contraindicated. Additional analgesic and opioid-sparing options such as wound instillation of local anesthetics, transversus abdominis plane blocks, dexamethasone, gabapentin, and ketamine may be used as appropriate in women at risk of severe postoperative pain or in women whose postoperative pain is not well controlled despite standard analgesic regimes.

    View details for PubMedID 28625307

  • Neuraxial Anesthesia in Obstetric Patients Receiving Thromboprophylaxis With Unfractionated or Low-Molecular-Weight Heparin: A Systematic Review of Spinal Epidural Hematoma. Anesthesia and analgesia Leffert, L. R., Dubois, H. M., Butwick, A. J., Carvalho, B. n., Houle, T. T., Landau, R. n. 2017; 125 (1): 223–31

    Abstract

    Venous thromboembolism remains a major source of morbidity and mortality in obstetrics with an incidence of 29.8/100,000 vaginal delivery hospitalizations; cesarean delivery confers a 4-fold increased risk of thromboembolism when compared with vaginal delivery. Revised national guidelines now stipulate that the majority of women delivering via cesarean and women at risk for ante- or postpartum venous thromboembolism receive mechanical or pharmacological thromboprophylaxis. This practice change has important implications for obstetric anesthesiologists concerned about the risk of spinal epidural hematoma (SEH) among anticoagulated women receiving neuraxial anesthesia. We conducted a systematic review of published English language studies (1952-2016) and of the US Anesthesia Closed Claims Project Database (1990-2013) to identify cases of SEH associated with neuraxial anesthesia and thromboprophylaxis. We also report on SEH in obstetric patients receiving thromboprophylaxis and neuraxial anesthesia without adherence to the American Society of Regional Anesthesia (ASRA) recommendations. In our review, we initially identified 736 publications of which 10 met inclusion criteria; these were combined with the 5 cases of SEH identified in 546 obstetric Anesthesia Closed Claims reviews. None of these publications revealed SEH associated with neuraxial anesthesia and thromboprophylaxis with unfractionated heparin or low-molecular-weight heparin in obstetric patients. Based on data from 6 reports, 28 parturients had their neuraxial blockade before the minimum ASRA recommended time interval between the last anticoagulant dose and the neuraxial procedure. Based on data from 2 reports, 52 parturients received neuraxial anesthesia without their low-molecular-weight heparin dose being discontinued during the intrapartum period. Although the very low level of evidence and high heterogeneity in these reports make it difficult to draw quantitative conclusions from this systematic review, it is encouraging that this comprehensive search did not identify a single case of SEH in an obstetric patient receiving thromboprophylaxis and neuraxial anesthesia. Analysis of large-scale registries (eg, the Anesthesia Incident Reporting System of the Anesthesia Quality Institute) with more granular clinical and pharmacological data is needed to assess the impact of these practice changes on obstetric SEH incidence. In the interim, optimal care of obstetric patients depends on multidisciplinary planning of anticoagulation dosing to facilitate neuraxial anesthesia and thoughtful weighing of the relative risks and benefits of providing versus withholding neuraxial in favor of general anesthesia.

    View details for PubMedID 28628578

  • Intrathecal Migration of an Epidural Catheter While Using a Programmed Intermittent Epidural Bolus Technique for Labor Analgesia Maintenance: A Case Report. A & A case reports Betti, F. n., Carvalho, B. n., Riley, E. T. 2017

    Abstract

    We describe a case of intrathecal migration of a wire-reinforced epidural catheter in a parturient who received epidural labor analgesia. Epidural analgesia was initiated with a combined-spinal epidural technique and maintained by programmed intermittent epidural boluses. Epidural catheter aspiration after insertion was negative for cerebrospinal fluid. The patient's response to the first four doses of local anesthetic was consistent with epidural drug delivery. After the fifth dose, she developed a complete lower extremity motor block, hypotension, and high sensory blockade. Catheter aspiration was then positive for cerebrospinal fluid. After symptom resolution, labor pain was successfully managed with this inadvertent intrathecal catheter.

    View details for PubMedID 28767472

  • Postpartum tubal ligation: A retrospective review of anesthetic management at a single institution and a practice survey of academic institutions. Journal of clinical anesthesia McKenzie, C. n., Akdagli, S. n., Abir, G. n., Carvalho, B. n. 2017; 43: 39–46

    Abstract

    The primary aim was to evaluate institutional anesthetic techniques utilized for postpartum tubal ligation (PPTL). Secondarily, academic institutions were surveyed on their clinical practice for PPTL.An institutional-specific retrospective review of patients with ICD-9 procedure codes for PPTL over a 2-year period was conducted. Obstetric anesthesia fellowship directors were surveyed on anesthetic management of PPTL.Labor and delivery unit. Internet survey.202 PPTL procedures were reviewed. 47 institutions were surveyed; 26 responses were received.Timing of PPTL, anesthetic management, postoperative pain and length of stay.There was an epidural catheter reactivation failure rate of 26% (18/69 epidural catheter reactivation attempts). Time from epidural catheter insertion to PPTL was a significant factor associated with failure: median [IQR; range] time for successful versus failed epidural catheter reactivation was 17h [10-25; 3-55] and 28h [14-33; 5-42], respectively (P=0.028). Epidural catheter reactivation failure led to significantly longer times to provide surgical anesthesia than successful epidural catheter reactivation or primary spinal technique: median [IQR] 41min [33-54] versus 15min [12-21] and 19min [15-24], respectively (P<0.0001). Fifty-eight percent (15/26) of respondents routinely leave the labor epidural catheter in-situ if PPTL is planned. Sixty-five percent (17/26) and 7% (2/26) would not attempt to reactivate the epidural catheter for PPTL if >8h and >24h post-delivery, respectively.Epidural catheter reactivation failure increases with longer intervals between catheter placement and PPTL. Failed epidural catheter reactivation increases anesthetic and operating room times. Our results and the significant variability in practice from our survey suggest recommendations on the timing and anesthetic management are needed to reduce unfulfilled PPTL procedures.

    View details for PubMedID 28985581

  • The impact of postpartum hemoglobin levels on maternal quality of life after delivery: a prospective exploratory study. Annals of hematology Miller, C. M., Ramachandran, B., Akbar, K., Carvalho, B., Butwick, A. J. 2016; 95 (12): 2049-2055

    Abstract

    Postpartum anemia has been associated with postpartum morbidities, such as depression and poor cognition. However, it is unclear whether postpartum anemia is associated with reduced health-related quality of life. We performed a prospective study to examine the relations between postpartum Hb levels with postpartum health-related quality of life (HRQoL). We collected data from 60 women intending vaginal delivery and assessed HRQoL and maternal fatigue on admission and on the first postpartum day using the RAND 36-Item Short-Form Health Survey (SF-36) and the Multidimensional Fatigue Inventory (MFI), respectively. Maternal Hb levels were measured on admission and on the first postpartum day. We also assessed patients for postpartum depression using the Edinburgh Postpartum Depression Scale (EPDS). We performed unadjusted and multivariate linear regression (adjusting for maternal age, parity, mode of delivery, and race) to assess the associations between postdelivery Hb with each subscale of the SF-36 and MFI. The mean predelivery and postpartum Hb levels were 12.3 (1.2) and 10.8 (1.4) g/dl, respectively. In our unadjusted and adjusted regression analyses, we observed no statistically significant associations between postpartum Hb levels with any SF-36 or MFI subscale (P > 0.05). Based on the EPDS, only one patient was depressed; her postpartum Hb was 11.2 g/dl. Our findings suggest that postpartum Hb levels may not influence HRQoL or fatigue. However, our findings may only apply to women without predelivery anemia, severe blood loss or moderate-to-severe anemia after delivery. Future studies are needed to determine whether postpartum Hb influences HRQoL among women with moderate or severe postpartum anemia.

    View details for PubMedID 27623626

  • In reply. International journal of obstetric anesthesia Van de Velde, M., Carvalho, B. 2016; 28: 96

    View details for DOI 10.1016/j.ijoa.2016.09.008

    View details for PubMedID 27836392

  • Moving Beyond the 0-10 Scale for Labor Pain Measurement. Anesthesia and analgesia Carvalho, B., Mhyre, J. M. 2016; 123 (6): 1351-1353

    View details for DOI 10.1213/ANE.0000000000001641

    View details for PubMedID 27861442

  • Analysis of Physiological Respiratory Variable Alarm Alerts Among Laboring Women Receiving Remifentanil. Anesthesia and analgesia Weiniger, C. F., Carvalho, B., Stocki, D., Einav, S. 2016: -?

    Abstract

    Remifentanil may be used by laboring women for analgesia, despite controversy because of potential apneas. We evaluated candidate variables as early warning alerts for apnea, based on prevalence, positive predictive rate, sensitivity for apnea event detection, and early warning alert time intervals (lead time) for apnea.We performed a secondary analysis of respiratory physiological data that had been collected during a prospective IRB-approved study of laboring women receiving IV patient-controlled boluses of remifentanil 20 to 60 μg every 1 to 2 minutes. Analyzed data included the respiratory rate (RR), end-tidal CO2 (EtCO2), pulse oximetry (SpO2), heart rate (HR), and the Integrated Pulmonary Index (IPI; Capnostream 20; Medtronic, Boulder, CO) that had been recorded continuously throughout labor. We defined immediate early warning alerts as any drop in a variable value below a prespecified threshold for 15 seconds: RR < 8 breaths per minute (bpm), EtCO2 < 15 mm Hg, and SpO2 < 92%. We defined alerts as "sustained" when the value remained below the threshold for ≥ 10 further seconds. The IPI value (1 to 10; 10 = healthy patient, ≤4 = immediate attention required, 1 = dire condition) was generated from a proprietary algorithm using RR, EtCO2, SpO2, and HR parameters. Apnea was defined as maximal CO2 < 5 mm Hg for at least 30 consecutive seconds.We counted 62 apneas, among 10 of 19 (52.6%) women who received remifentanil (total dose 1725 ± 1392 μg, administered over 160 ± 132 minutes). We counted 331 immediate early warning alerts for the variables; 271 (82%) alerts were sustained for ≥10 seconds. The positive predictive value of alerts for apnea was 35.8% (99% confidence interval [CI]: 27.1-45.6), 28.9% (99% CI: 20.8-38.7), 4.3% (99% CI: 1.9-9.6), and 24.6% (99% CI: 18.3-32.2) for RR, EtCO2, SpO2, and IPI, respectively. The sensitivity for apnea event detection was 100% (99% CI: 90.3-100) for RR (<8 bpm) and IPI (≤4); 75.8% (99% CI: 59.8-86.9) for EtCO2 <15 mm Hg; and 14.5% (99% CI: 6.5-29.4) for SpO2 <92%. We found a statistically significant difference in the timing of RR, EtCO2, SpO2, and IPI alerts for apnea; Friedman's Q = 33.53; P < .0001. The EtCO2 had a median (interquartile range) lead time of -0.2 (-12.2 to 0.7) seconds, and SpO2 had a median (interquartile range) lead time of 40.0 (40.0 to 40.0) seconds.The majority of women receiving IV remifentanil for labor analgesia experienced apneas. Alerts for EtCO2 (<15 mm Hg), RR (<8 bpm), and IPI (≤4) detected most apneas, whereas SpO2 alerts missed the majority of apneas. All variables had a low positive predictive rate, demonstrating the limitations of the respiratory monitors utilized as early warning surveillance for apneas in this setting.

    View details for PubMedID 27870644

  • Survey of external cephalic version for breech presentation and neuraxial blockade use. Journal of clinical anesthesia Weiniger, C. F., Sultan, P., Dunn, A., Carvalho, B. 2016; 34: 616-622

    Abstract

    Neuraxial blockade may increase external cephalic version (ECV) success rates. This survey aimed to assess the frequency and characteristics of neuraxial blockade used to facilitate ECV.We surveyed Society for Obstetric Anesthesia and Perinatology members regarding ECV practice using a 15-item survey developed by 3 obstetric anesthesiologists and tested for face validity. The survey was e-mailed in January 2015 and again in February 2015 to the 1056 Society of Obstetric Anesthesiology and Perinatology members. We present descriptive statistics of responses.Our survey response rate was 322 of 1056 (30.5%).Neuraxial blockade was used for ECV always by 18 (5.6%), often by 52 (16.1%), sometimes by 98 (30.4%), rarely by 78 (24.2%), and never by 46 (14.3%) of respondents. An anesthetic sensory block target was selected by 141 (43.8%) respondents, and analgesic by 102 (31.7%) respondents. Epidural drug doses ranged widely, including sufentanil 5-25 μg; lidocaine 1% or 2% 10-20 mL, bupivacaine 0.0625% to 0.5% 6-15 mL, and ropivacaine 0.2% 20 mL. Intrathecal bupivacaine was used by 182 (56.5%) respondents; the most frequent doses were 2.5 mg used by 24 (7.5%), 7.5 mg used by 35 (10.9%), and 12 mg used by 30 (9.3%).Neuraxial blockade is not universally offered to facilitate ECV, and there is wide variability in neuraxial blockade techniques, in drugs and doses administered, and in the sensory blockade (anesthetic or analgesic) targeted. Future studies need to evaluate and remove barriers to allow for more widespread use of neuraxial blockade for pain relief and to optimize ECV success rates.

    View details for DOI 10.1016/j.jclinane.2016.05.040

    View details for PubMedID 27687460

  • Neuraxial blockade increases external cephalic version success: a well-known finding needing to be disseminated within the obstetric domain AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY Sultan, P., Weiniger, C. F., Carvalho, B. 2016; 215 (5): 675–76

    View details for PubMedID 27423524

  • Mapping the Fetomaternal Peripheral Immune System at Term Pregnancy. Journal of immunology Fragiadakis, G. K., Baca, Q. J., Gherardini, P. F., Ganio, E. A., Gaudilliere, D. K., Tingle, M., Lancero, H. L., McNeil, L. S., Spitzer, M. H., Wong, R. J., Shaw, G. M., Darmstadt, G. L., Sylvester, K. G., Winn, V. D., Carvalho, B., Lewis, D. B., Stevenson, D. K., Nolan, G. P., Aghaeepour, N., Angst, M. S., Gaudilliere, B. L. 2016

    Abstract

    Preterm labor and infections are the leading causes of neonatal deaths worldwide. During pregnancy, immunological cross talk between the mother and her fetus is critical for the maintenance of pregnancy and the delivery of an immunocompetent neonate. A precise understanding of healthy fetomaternal immunity is the important first step to identifying dysregulated immune mechanisms driving adverse maternal or neonatal outcomes. This study combined single-cell mass cytometry of paired peripheral and umbilical cord blood samples from mothers and their neonates with a graphical approach developed for the visualization of high-dimensional data to provide a high-resolution reference map of the cellular composition and functional organization of the healthy fetal and maternal immune systems at birth. The approach enabled mapping of known phenotypical and functional characteristics of fetal immunity (including the functional hyperresponsiveness of CD4(+) and CD8(+) T cells and the global blunting of innate immune responses). It also allowed discovery of new properties that distinguish the fetal and maternal immune systems. For example, examination of paired samples revealed differences in endogenous signaling tone that are unique to a mother and her offspring, including increased ERK1/2, MAPK-activated protein kinase 2, rpS6, and CREB phosphorylation in fetal Tbet(+)CD4(+) T cells, CD8(+) T cells, B cells, and CD56(lo)CD16(+) NK cells and decreased ERK1/2, MAPK-activated protein kinase 2, and STAT1 phosphorylation in fetal intermediate and nonclassical monocytes. This highly interactive functional map of healthy fetomaternal immunity builds the core reference for a growing data repository that will allow inferring deviations from normal associated with adverse maternal and neonatal outcomes.

    View details for PubMedID 27793998

  • Implementation of Programmed Intermittent Epidural Bolus for the Maintenance of Labor Analgesia. Anesthesia and analgesia Carvalho, B., George, R. B., Cobb, B., McKenzie, C., Riley, E. T. 2016; 123 (4): 965-971

    Abstract

    Programmed intermittent epidural bolus (PIEB) is an exciting new technology that has the potential to improve the maintenance of epidural labor analgesia. PIEB compared with a continuous epidural infusion (CEI) has the potential advantage of greater spread within the epidural space and therefore better sensory blockade. Studies have demonstrated a local anesthetic-sparing effect, fewer instrumental vaginal deliveries, less motor blockade, and improvements in maternal satisfaction with PIEB compared with CEI. However, the optimal PIEB regimen and pump settings remain unknown, and there are a number of logistical issues and practical considerations that should be considered when implementing PIEB. The PIEB bolus size and interval, PIEB start time delay period, and patient-controlled epidural analgesia bolus size and lockout time can influence the efficacy of PIEB used for epidural labor analgesia. Educating all members of the health care team is critical to the success of the technique. This review summarizes the role of PIEB for the maintenance of labor analgesia, outlines implementation strategies, suggests optimal settings, and presents potential limitations of the technique.

    View details for DOI 10.1213/ANE.0000000000001407

    View details for PubMedID 27464978

  • Clinical and microbiological features of maternal sepsis: a retrospective study. International journal of obstetric anesthesia Abir, G., Akdagli, S., Butwick, A., Carvalho, B. 2016

    Abstract

    Identifying pregnant women with sepsis is challenging because diagnostic clinical and laboratory criteria overlap with normal pregnant physiologic indices. Our primary study aim was to describe clinical and laboratory characteristics of women diagnosed with sepsis, severe sepsis and septic shock. Our secondary aim was to determine positive predictive values for International Classification of Disease (ICD)-9 billing codes for sepsis, severe sepsis, and septic shock.After gaining Institutional Review Board approval, we identified women with ICD-9 codes for sepsis, severe sepsis and septic shock who were admitted to a single tertiary obstetric center from 2007-2013. Diagnoses were confirmed using criteria from the International Sepsis Definitions Conference report. Demographic, obstetric, vital signs and laboratory data were abstracted by medical chart review.We identified 190 women with sepsis-related ICD-9 codes: of these, 35 (18%) women met the criteria for a clinical diagnosis of sepsis, severe sepsis or septic shock. Twenty (57%) women had a sepsis-related diagnosis after cesarean delivery. Twenty-one (60%) women had one or more pre-existing medical conditions and 19 (54%) women had one or more obstetric-related conditions. The genital tract was the most common site of infection. We observed considerable heterogeneity in maternal vital signs and laboratory indices for women with ICD-9 codes for sepsis, severe sepsis, and septic shock. The positive predictive value for each sepsis-related ICD-9 code was low: 16% (95% CI 10 to 24%) for sepsis, 10% (95% CI 3 to 25%) for severe sepsis and 24% (95% CI 10 to 46%) for septic shock.We identified marked heterogeneity in patient characteristics, clinical features, laboratory indices and microbiological findings among cohorts of women diagnosed with maternal sepsis, severe sepsis or septic shock. Based on our findings, the incidence of maternal sepsis using ICD-9 codes may be significantly overestimated.

    View details for DOI 10.1016/j.ijoa.2016.09.003

    View details for PubMedID 27793427

  • In reply. International journal of obstetric anesthesia Van de Velde, M., Carvalho, B. 2016; 27: 92-3

    View details for DOI 10.1016/j.ijoa.2016.06.007

    View details for PubMedID 27432691

  • In reply. International journal of obstetric anesthesia Van de Velde, M., Carvalho, B. 2016; 27: 90

    View details for DOI 10.1016/j.ijoa.2016.05.002

    View details for PubMedID 27297336

  • Reply to Dr Kumar. Regional anesthesia and pain medicine McKenzie, C. P., Carvalho, B., Riley, E. T. 2016; 41 (4): 547-?

    View details for DOI 10.1097/AAP.0000000000000433

    View details for PubMedID 27315183

  • Challenging the 4-to 5-minute rule: from perimortem cesarean to resuscitative hysterotomy AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY Lipman, S. S., Cohen, S., Mhyre, J., Carvalho, B., Einav, S., Arafeh, J., Jeejeebhoy, F., Cobb, B., Druzin, M., Katz, V., Harney, K. 2016; 215 (1): 129-131

    View details for DOI 10.1016/j.ajog.2016.03.043

    View details for PubMedID 27040085

  • The Effect of Intrathecal Morphine Dose on Outcomes After Elective Cesarean Delivery: A Meta-Analysis ANESTHESIA AND ANALGESIA Sultan, P., Halpern, S. H., Pushpanathan, E., Patel, S., Carvalho, B. 2016; 123 (1): 154-164

    Abstract

    The intrathecal morphine dose achieving optimal analgesia for cesarean delivery while minimizing side effects has not yet been deduced. In this meta-analysis, our objective was to determine whether low- or high-dose intrathecal morphine provides acceptable duration and intensity of analgesia with fewer side effects.A literature search (PubMed, EMBASE, MEDLINE, Scopus, Web of Science, and CINAHL) was performed to identify randomized controlled trials involving patients undergoing elective cesarean delivery under spinal anesthesia comparing low-dose (LD; 50-100 μg) morphine with higher dose (HD; >100-250 μg). The primary outcome was the time for first request for supplemental analgesia. The secondary outcomes included pain scores, morphine use, maternal side effects (vomiting and pruritus), and Apgar scores. Mean differences (MDs) and odds ratios (ORs) were calculated using random effects modeling with 95% confidence intervals (CIs).Eleven articles met our inclusion criteria. Four hundred eighty patients were recruited in all study groups (233 patients in the HD and 247 in the LD groups). The mean time to first analgesic request was longer (MD, 4.49 hours [95% CI, 1.85-7.13]; P = 0.0008) in the HD group compared with the LD group. Pain scores (0-100 scale) at 12 hours (MD, 2.54 [95% CI, -2.55 to 7.63]; P = 0.33) as well as morphine consumption at 24 hours (MD, 1.31 mg [95% CI, -3.06 to 7.31]; P = 0.42) were not significantly different. The incidence of nausea or vomiting (OR, 0.44 [95% CI, 0.27-0.73]; P = 0.002) and pruritus (OR, 0.34 [95% CI, 0.20-0.59]; P = 0.0001) was lower in the LD group. The incidence of Apgar scores <7 at 1 minute was not different between groups (OR, 1.11 [95% CI, 0.06-20.49]; P = 0.94).This meta-analysis shows that HDs of intrathecal morphine prolong analgesia after cesarean delivery compared with lower doses. The MD of 4.5 hours (95% CI, 1.9-7.1 and 99% CI, 1.0-8.2 hours) of pain relief must be balanced against the increased risk of maternal pruritus and vomiting. Results from this study can be used by clinicians to weigh the benefits and potential side effects of using HDs of intrathecal morphine for cesarean delivery.

    View details for DOI 10.1213/ANE.0000000000001255

    View details for PubMedID 27089000

  • Amniotic fluid embolism: update and review CURRENT OPINION IN ANESTHESIOLOGY Sultan, P., Seligman, K., Carvalho, B. 2016; 29 (3): 288-296

    Abstract

    This article reviews our current understanding of amniotic fluid embolism (AFE), specifically the pathogenesis, treatment strategies, potential diagnostic tests and future therapeutic interventions for AFE.The incidence and case mortality of AFE varies widely because of heterogeneous diagnostic criteria and varying reporting mechanisms across the world. Amniotic fluid embolism is thought to be caused by abnormal activation of immunologic mechanisms following entry of fetal antigens into maternal circulation. Mast cell degranulation and complement activation may play a role in this anaphylactoid or systemic inflammatory response syndrome. Development of serum biomarkers and immune-histochemical staining techniques to aid diagnosis and develop treatments are under development and evaluation. Treatment of AFE is supportive and directed at treating cardiovascular, pulmonary, and coagulation derangements. Treatment for coagulopathy (fresh frozen plasma, cryoprecipitate/fibrinogen concentrate, and antifibrinolytics) should be initiated promptly. Recombinant factor VIIa may lead to increased mortality and should not routinely be used. C1 esterase inhibitors may be a potential therapeutic option.AFE is a devastating obstetric complication that requires early and aggressive intervention with optimal cardiopulmonary resuscitation, as well as hemorrhage and coagulopathy management. Biomarkers offer promise to aid the diagnosis of AFE, and immunomodulation may provide future therapeutic interventions to treat this lethal condition.

    View details for DOI 10.1097/ACO.0000000000000328

    View details for PubMedID 27153475

  • Pharmacokinetics and placental transfer of magnesium sulfate in pregnant women AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY Brookfield, K. F., Su, F., Elkomy, M. H., Drover, D. R., Lyell, D. J., Carvalho, B. 2016; 214 (6)

    Abstract

    Magnesium sulfate is one of the most commonly prescribed intravenous medications in obstetrics. Despite its widespread use, there are limited data about magnesium pharmacokinetics, and magnesium is prescribed empirically without dose adjustment for different indications.The aim of this study was to characterize the pharmacokinetics and placental transfer of magnesium sulfate in pregnant women and to determine key covariates that impact the pharmacokinetics.This is a prospective pharmacokinetic cohort study of pregnant women who were prescribed magnesium sulfate for preeclampsia, preterm labor, or extreme prematurity. Women received a 4-g loading dose and 2 g/h maintenance dose as clinically indicated. Maternal blood samples were obtained before and at multiple time points during and after magnesium administration. Cord blood also was sampled at delivery. A population pharmacokinetic approach that used a nonlinear mixed-effects modeling was used to characterize magnesium disposition.Pharmacokinetic profiles of 111 pregnant women were analyzed. Magnesium clearance was 3.98 L/h in preeclamptic women and 5.88 L/h non-preeclamptic women. Steady-state concentration of magnesium was 7.2 mg/dL in preeclamptic women compared with 5.1 mg/dL in non-preeclamptic women. Maternal weight significantly impacted time to steady state. The ratio of the mean umbilical vein magnesium level to the mean maternal serum magnesium level at the time of delivery was 0.94 ± 0.15.The study accurately characterizes the pharmacokinetics of magnesium administered to pregnant women. Preeclamptic status and maternal weight significantly impact serum magnesium levels. This pharmacokinetic model could be applied to larger cohorts to help tailor magnesium treatment and account for these covariates.

    View details for DOI 10.1016/j.ajog.2015.12.060

    View details for PubMedID 26767791

  • The Wiley Spinal Catheter-Over-Needle System for Continuous Spinal Anesthesia A Case Series of 5 Cesarean Deliveries Complicated by Paresthesias and Headaches REGIONAL ANESTHESIA AND PAIN MEDICINE McKenzie, C. P., Carvalho, B., Riley, E. T. 2016; 41 (3): 405-410

    Abstract

    Intrathecal catheter devices using a catheter-over-needle design and softer flexible material have been introduced to clinical practice with the aim of reducing some of the complications such as postdural puncture headaches and paresthesias seen with previous versions of intrathecal catheters. We present a case series of 5 cesarean deliveries using the Wiley Spinal intrathecal system (Epimed, Johnstown, New York), which was recently approved by the US Food and Drug Administration. The intrathecal catheter system consists of a flexible 23-gauge intrathecal cannula over a 27-gauge pencil-point spinal needle. The placement of the intrathecal catheter was successful in all 5 cases; however, paresthesias in 3 cases and postdural puncture headaches in 2 cases complicated the placement and use of the device. Although the unique catheter-over-needle design facilitates the use of smaller-gauge spinal needles for dural puncture and larger-gauge catheters for medication administration, this case series using the Wiley Spinal suggests that paresthesias and postdural puncture headaches may still limit its widespread utilization. Future studies are needed to determine the true incidence of complications and to determine the role of continuous spinal anesthesia in the obstetric population.

    View details for DOI 10.1097/AAP.0000000000000367

    View details for Web of Science ID 000378154200017

    View details for PubMedID 26909488

  • Programmed intermittent epidural boluses for maintenance of labor analgesia: an impact study INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA McKenzie, C. P., Cobb, B., Riley, E. T., Carvalho, B. 2016; 26: 32-38

    Abstract

    The aim of this impact study was to compare the analgesic efficacy and side effect profile of programmed intermittent epidural boluses (PIEB)+patient-controlled epidural analgesia (PCEA) to continuous epidural infusion (CEI)+PCEA for maintenance labor analgesia after the introduction of PIEB at our institution.We conducted a retrospective analysis after replacing the background CEI with PIEB for our labor PCEA. Pre-change pump settings were CEI 12mL/h with PCEA (12mL bolus, lockout 15min); PIEB settings were a 9mL bolus every 45min with PCEA (10mL bolus, lockout 10min). We compared medical records of all women receiving epidural or combined spinal-epidural labor analgesia for vaginal delivery for two months before PIEB implementation to a two-month period of PIEB utilization following a five-month introductory familiarization period. The primary outcome was the proportion of women requiring rescue clinician boluses.Fewer patients in the PIEB group required rescue clinician boluses compared to the CEI group (12% vs. 19%, P=0.012). Time to first rescue bolus request and total bolus dose were not different. Peak (median [IQR]) pain scores were 2[0-5] with CEI and 0[0-4] with PIEB. There was no difference in instrumental delivery rates.Using PIEB compared to CEI as the background maintenance epidural analgesia method in conjunction with PCEA reduced the number of women requiring clinician rescue boluses while providing comparable labor analgesia. The findings of this clinical care impact study confirm the results of randomized controlled studies and suggest PIEB may be a preferable technique to CEI for the maintenance of labor analgesia.

    View details for DOI 10.1016/j.ijoa.2015.11.005

    View details for Web of Science ID 000376707400007

    View details for PubMedID 26775896

  • Active Warming Utilizing Combined IV Fluid and Forced-Air Warming Decreases Hypothermia and Improves Maternal Comfort During Cesarean Delivery: A Randomized Control Trial ANESTHESIA AND ANALGESIA Cobb, B., Cho, Y., Hilton, G., Ting, V., Carvalho, B. 2016; 122 (5): 1490-1497

    Abstract

    The aim of this study was to apply both IV fluid and forced-air warming to decrease perioperative hypothermia in women undergoing cesarean delivery with spinal anesthesia. The authors hypothesize that combined-modality active warming (AW) would increase maternal temperature on arrival at the postanesthesia care unit (PACU) and decrease the incidence of maternal perioperative hypothermia (<36°C) compared with no AW.Forty-six healthy women (n = 23 per group) undergoing scheduled cesarean delivery with spinal anesthesia (10-12 mg bupivacaine + 10 μg fentanyl) were enrolled in this double-blinded, randomized controlled trial. Women were randomly assigned to receive either AW (warmed IV fluid and lower body forced-air warmer) or no warming (NW; blankets only). SpotOn Monitoring System was used to measure core temperature intraoperatively and for 1 hour postoperatively. The primary outcome measure was maternal temperature on arrival at the PACU. Secondary outcome measures included incidence of maternal perioperative hypothermia (<36°C), incidence of shivering, thermal comfort scores (0-100 scale), Apgar scores, and umbilical cord blood gas analysis.Demographic, obstetric, and surgical data were similar between study groups. The AW group (35.9°C ± 0.5°C) had a significantly higher temperature on arrival at the PACU compared with the NW group (35.5°C ± 0.5°C, P = 0.006; 95% confidence interval of mean difference, 0.1°C-0.7°C). Fourteen (64%) women in the AW group and 20 (91%) in the NW group were hypothermic during the study period (P = 0.031). Median (interquartile range) thermal comfort scores were 100 (95-100) in the AW group and 90 (70-100) in the NW group (P = 0.008). There were no significant differences in the incidence of intraoperative shivering (22% in the AW and 45% in the NW groups; P = 0.11), Apgar scores, or umbilical vein blood gas values between the study groups.Fluid combined with forced-air warming is effective in decreasing the incidence of perioperative hypothermia and improving maternal thermal comfort. However, despite multimodal AW, the majority of women became hypothermic, and shivering was not prevented. The findings suggest that combined AW for cesarean delivery with spinal anesthesia is difficult, and only modest benefit should be expected.

    View details for DOI 10.1213/ANE.0000000000001181

    View details for Web of Science ID 000374664400040

    View details for PubMedID 26895002

  • Pharmacokinetics and Pharmacodynamics of Drugs Commonly Used in Pregnancy and Parturition. Anesthesia and analgesia Ansari, J., Carvalho, B., Shafer, S. L., Flood, P. 2016; 122 (3): 786-804

    Abstract

    The majority of pregnant women will be treated with a medication other than a vitamin supplement during their pregnancy. Almost half of these medications will be category C or D according to the former US Food and Drug Administration classification system, indicating a lack of human studies with animal studies suggesting adverse fetal effects (category C) or evidence of risk in humans (category D). Changes in maternal physiology alter drug bioavailability, distribution, clearance, and thus the drug half-life in often unpredictable ways. For many drugs, good pharmacokinetic and pharmacodynamic data in pregnancy and parturition are lacking. For other drugs, recent studies demonstrate major pharmacokinetic or pharmacodynamic changes that require dose adjustment in pregnancy, but current dosing guidelines do not reflect these data. In this review, we address the principles that underlie changes in pharmacology and physiology in pregnancy and provide information on drugs that anesthesiologists commonly encounter in treating pregnant patients.

    View details for DOI 10.1213/ANE.0000000000001143

    View details for PubMedID 26891392

  • A Longitudinal Study to Evaluate Pregnancy-Induced Endogenous Analgesia and Pain Modulation REGIONAL ANESTHESIA AND PAIN MEDICINE Carvalho, B., Granot, M., Sultan, P., Wilson, H., Landau, R. 2016; 41 (2): 175-180

    Abstract

    The phenomenon of pregnancy-induced analgesia has been demonstrated in animal models but less consistently in human studies. This study aimed to assess endogenous pain modulation, evaluating inhibitory and excitatory pain pathways, over the course of pregnancy and postpartum.Healthy pregnant women were approached for participation in this prospective multicenter cohort study. Conditioned pain modulation (CPM), mechanical temporal summation (mTS), and temperature that induced pain 6 out of 10 (pain-6) were assessed toward the end of each trimester of pregnancy (8-12, 18-22, and 36 weeks) and at 6 to 12 weeks postpartum. To assess how pregnancy affects CPM, mTS, and pain-6, a mixed-effects analysis of variance was performed.Thirty-three pregnant women were enrolled. Pregnancy did not significantly impact CPM (F3,39 = 0.30, P = 0.83, partial η = 0.02), and there was no significant difference between CPM scores in the third trimester compared with postpartum. The mTS scores and pain-6 ratings were also not significantly changed by pregnancy (F3,42 = 1.20, P = 0.32, partial η = 0.08; and F3,42 = 1.90, P = 0.14, partial η = 0.12, respectively).This is the first study to assess CPM and mTS changes in pregnancy and postpartum. Endogenous pain modulation evaluating both inhibitory and excitatory pain pathways did not significantly change during pregnancy or postpartum. Future studies are required to determine the magnitude and clinical significance of pregnancy-induced analgesia.

    View details for DOI 10.1097/AAP.0000000000000359

    View details for PubMedID 26866295

  • Checklists and multidisciplinary team performance during simulated obstetric hemorrhage. International journal of obstetric anesthesia Hilton, G., Daniels, K., Goldhaber-Fiebert, S. N., Lipman, S., Carvalho, B., Butwick, A. 2016; 25: 9-16

    Abstract

    Checklists can optimize team performance during medical crises. However, there has been limited examination of checklist use during obstetric crises. In this simulation study we exposed multidisciplinary teams to checklist training to evaluate checklist use and team performance during a severe postpartum hemorrhage.Fourteen multidisciplinary teams participated in a postpartum hemorrhage simulation occurring after vaginal delivery. Before participating, each team received checklist training. The primary study outcome was whether each team used the checklist during the simulation. Secondary outcomes were the times taken to activate our institution-specific massive transfusion protocol and commence red blood cell transfusion, and whether a designated checklist reader was used.The majority of teams (12/14 (86%)) used the checklist. Red blood cell transfusion was administered by all teams. The median [IQR] times taken to activate the massive transfusion protocol and transfuse red blood cells were 5min 14s [3:23-6:43] and 14min 40s [12:56-17:28], respectively. A designated checklist reader was used by 7/12 (58%) teams that used the checklist. Among teams that used a checklist with versus without a designated reader, we observed no differences in the times to activate the massive transfusion protocol or to commence red blood cell transfusion (P>0.05).Although checklist training was effective in promoting checklist use, multidisciplinary teams varied in their scope of checklist use during a postpartum hemorrhage simulation. Future studies are required to determine whether structured checklist training can result in more standardized checklist use during a postpartum hemorrhage.

    View details for DOI 10.1016/j.ijoa.2015.08.011

    View details for PubMedID 26421705

  • Remifentanil for labor analgesia: an evidence-based narrative review INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Van de Velde, M., Carvalho, B. 2016; 25: 66-74

    Abstract

    This manuscript reviews the available literature on remifentanil patient-controlled intravenous analgesia in labor focusing on efficacy and safety. Remifentanil compares favorably to other potent systemic opioids but with fewer opioid-related neonatal effects. However, remifentanil provides modest and short-lasting labor analgesia that is consistently inferior when compared to neuraxial analgesia. The initial analgesic effect provided with remifentanil also diminishes as labor progresses. In several studies, remifentanil induced significant respiratory depressant effects in laboring women with episodes of desaturation, hypoventilation and even apnea. Given the safety concerns, we recommend that remifentanil patient-controlled intravenous analgesia should not be a routine analgesia technique during labor. In cases where neuraxial analgesia is refused or contraindicated and the use of remifentanil justified, continuous and careful monitoring is required to detect respiratory depression to provide safe care of both the pregnant woman and unborn child.

    View details for DOI 10.1016/j.ijoa.2015.12.004

    View details for Web of Science ID 000370109900011

    View details for PubMedID 26777438

  • Simulation Study Assessing Healthcare Provider's Knowledge of Pre-Eclampsia and Eclampsia in a Tertiary Referral Center. Simulation in healthcare Hilton, G., Daniels, K., Carvalho, B. 2016; 11 (1): 25-31

    Abstract

    The aim of the study was to assess knowledge of labor and delivery healthcare providers at a tertiary referral center in the management of pre-eclampsia and eclampsia.Thirteen multidisciplinary teams participated in this institutional review board-exempt study. Each group encountered the same scenario that involved a pre-eclamptic parturient who progressed to eclampsia. The participants were unaware of the scenario topic before the drill and that key interventions would be recorded and timed. Seven of 13 groups were randomized to have a cognitive aid available.Twelve of 13 groups attempted to lower the blood pressure; however, only 7 of 12 groups used the correct first-line antihypertensive medication as per the American College of Obstetricians and Gynecologists' guidelines. All groups requested and administered the correct bolus dose of magnesium (4-6 g intravenously). Only 2 of 13 groups took appropriate action to lower the blood pressure to a "safe range" before induction of general anesthesia, and 4 of the 13 anesthesiologists made drug modifications for induction of anesthesia. None of the 7 groups randomized to have a cognitive aid used it.Our results show widespread magnesium sulfate utilization; however, the use of antihypertensive medication is not universally administered in compliance with current guidelines. The importance of blood pressure management to reduce maternal morbidity and mortality in the setting of pre-eclampsia needs to be emphasized. Interestingly, availability of a cognitive aid did not ensure its utilization in this scenario. Findings suggest that for cognitive aids to be effectively used, it is essential that staff has been trained and become familiar with them before an emergent event.

    View details for DOI 10.1097/SIH.0000000000000125

    View details for PubMedID 26836465

  • A Prospective Cohort Study Evaluating the Ability of Anticipated Pain, Perceived Analgesic Needs, and Psychological Traits to Predict Pain and Analgesic Usage following Cesarean Delivery. Anesthesiology research and practice Carvalho, B., Zheng, M., Harter, S., Sultan, P. 2016; 2016: 7948412-?

    Abstract

    Introduction. This study aimed to determine if preoperative psychological tests combined with simple pain prediction ratings could predict pain intensity and analgesic usage following cesarean delivery (CD). Methods. 50 healthy women undergoing scheduled CD with spinal anesthesia comprised the prospective study cohort. Preoperative predictors included 4 validated psychological questionnaires (Anxiety Sensitivity Index (ASI), Fear of Pain (FPQ), Pain Catastrophizing Scale, and Eysenck Personality Questionnaire) and 3 simple ratings: expected postoperative pain (0-10), anticipated analgesic threshold (0-10), and perceived analgesic needs (0-10). Postoperative outcome measures included post-CD pain (combined rest and movement) and opioid used for the 48-hour study period. Results. Bivariate correlations were significant with expected pain and opioid usage (r = 0.349), anticipated analgesic threshold and post-CD pain (r = -0.349), and perceived analgesic needs and post-CD pain (r = 0.313). Multiple linear regression analysis found that expected postoperative pain and anticipated analgesic needs contributed to post-CD pain prediction modeling (R (2) = 0.443, p < 0.0001); expected postoperative pain, ASI, and FPQ were associated with opioid usage (R (2) = 0.421, p < 0.0001). Conclusion. Preoperative psychological tests combined with simple pain prediction ratings accounted for 44% and 42% of pain and analgesic use variance, respectively. Preoperatively determined expected postoperative pain and perceived analgesic needs appear to be useful predictors for post-CD pain and analgesic requirements.

    View details for DOI 10.1155/2016/7948412

    View details for PubMedID 27143966

  • Cardiac Arrest in Pregnancy: A Scientific Statement From the American Heart Association. Circulation Jeejeebhoy, F. M., Zelop, C. M., Lipman, S., Carvalho, B., Joglar, J., Mhyre, J. M., Katz, V. L., Lapinsky, S. E., Einav, S., Warnes, C. A., Page, R. L., Griffin, R. E., Jain, A., Dainty, K. N., Arafeh, J., Windrim, R., Koren, G., Callaway, C. W. 2015; 132 (18): 1747-1773

    Abstract

    This is the first scientific statement from the American Heart Association on maternal resuscitation. This document will provide readers with up-to-date and comprehensive information, guidelines, and recommendations for all aspects of maternal resuscitation. Maternal resuscitation is an acute event that involves many subspecialties and allied health providers; this document will be relevant to all healthcare providers who are involved in resuscitation and specifically maternal resuscitation.

    View details for DOI 10.1161/CIR.0000000000000300

    View details for PubMedID 26443610

  • Utilization of spinal anesthesia for external cephalic version: a clinical practice cohort analysis INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Weiniger, C. F., Ezra, Y., Dunn, A. L., Carvalho, B. 2015; 24 (4): 389-390

    View details for DOI 10.1016/j.ijoa.2015.06.005

    View details for Web of Science ID 000364255300013

    View details for PubMedID 26303753

  • The Effect of patient warming during Caesarean delivery on maternal and neonatal outcomes: a meta-analysis BRITISH JOURNAL OF ANAESTHESIA Sultan, P., Habib, A. S., Cho, Y., Carvalho, B. 2015; 115 (4): 500-510

    Abstract

    Perioperative warming is recommended for surgery under anaesthesia, however its role during Caesarean delivery remains unclear. This meta-analysis aimed to determine the efficacy of active warming on outcomes after elective Caesarean delivery.We searched databases for randomized controlled trials utilizing forced air warming or warmed fluid within 30 min of neuraxial anaesthesia placement. Primary outcome was maximum temperature change. Secondary outcomes included maternal (end of surgery temperature, shivering, thermal comfort, hypothermia) and neonatal (temperature, umbilical cord pH and Apgar scores) outcomes. Standardized mean difference/mean difference/risk ratio (SMD/MD/RR) and 95% confidence interval (CI) were calculated using random effects modelling (CMA, version 2, 2005).13 studies met our criteria and 789 patients (416 warmed and 373 controls) were analysed for the primary outcome. Warming reduced temperature change (SMD -1.27°C [-1.86, -0.69]; P=0.00002); resulted in higher end of surgery temperatures (MD 0.43 °C [0.27, 0.59]; P<0.00001); was associated with less shivering (RR 0.58 [0.43, 0.79]; P=0.0004); improved thermal comfort (SMD 0.90 [0.36, 1.45]; P=0.001), and decreased hypothermia (RR 0.66 [0.50, 0.87]; P=0.003). Umbilical artery pH was higher in the warmed group (MD 0.02 [0, 0.05]; P=0.04). Egger's test (P=0.001) and contour-enhanced funnel plot suggest a risk of publication bias for the primary outcome of temperature change.Active warming for elective Caesarean delivery decreases perioperative temperature reduction and the incidence of hypothermia and shivering. These findings suggest that forced air warming or warmed fluid should be used for elective Caesarean delivery.

    View details for DOI 10.1093/bja/aev325

    View details for Web of Science ID 000362305700007

    View details for PubMedID 26385660

    View details for PubMedCentralID PMC4574493

  • Scheduled acetaminophen with as-needed opioids compared to as-needed acetaminophen plus opioids for post-cesarean pain management. International journal of obstetric anesthesia Valentine, A. R., Carvalho, B., Lazo, T. A., Riley, E. T. 2015; 24 (3): 210-216

    Abstract

    Combination opioid-acetaminophen drugs are commonly used for pain management after cesarean delivery. The aim of this study was to determine if scheduled acetaminophen decreases opioid use compared to as-needed combination acetaminophen-opioid administration.We performed a retrospective chart review of women who underwent cesarean delivery before and after a clinical practice change. All patients received spinal anesthesia containing intrathecal morphine 200μg and scheduled non-steroidal anti-inflammatory drugs for 48h postoperatively. The first group (As-Needed Group, n=120) received combination oral opioid-acetaminophen analgesics as needed for breakthrough pain. The second group (Scheduled Group, n=120) received oral acetaminophen 650mg every 6h for 48h postoperatively with oral oxycodone administered as needed for breakthrough pain. The primary outcome was opioid use, measured in intravenous morphine mg equivalents, in the first 48h postoperatively.The Scheduled Group used 9.1±2.1mg (95% CI 5.0-13.2) fewer intravenous morphine equivalents than the As-Needed Group (P <0.0001) over the study period. Fewer patients in the Scheduled Group exceeded acetaminophen 3g daily compared to the As-Needed Group (P=0.008). Pain scores were similar between study groups.After cesarean delivery, scheduled acetaminophen results in decreased opioid use and more consistent acetaminophen intake compared to acetaminophen administered as needed via combination acetaminophen-opioid analgesics, without compromising analgesia.

    View details for DOI 10.1016/j.ijoa.2015.03.006

    View details for PubMedID 25936786

  • Intact Survival After Obstetric Hemorrhage and 55 Minutes of Cardiopulmonary Resuscitation. A & A case reports Anast, N., Kwok, J., Carvalho, B., Lipman, S., Flood, P. 2015; 5 (1): 9-12

    Abstract

    Cardiac arrest occurs in approximately 1:12,000 parturients. Among nonpregnant patients who have in-hospital cardiac arrest, those whose spontaneous circulation does not return within 15 to 20 minutes have a high risk of death and disability, so life support efforts are generally stopped after this period. However, among parturients, witnessed in-hospital arrest is often reversible and has a better prognosis. We describe a successful clinical outcome after maternal cardiac arrest and 55 minutes of advanced cardiac life support. This case underscores the importance of high-quality cardiopulmonary resuscitation and raises questions about the appropriate duration of resuscitation efforts in otherwise healthy young mothers with a potentially reversible cause of arrest.

    View details for DOI 10.1213/XAA.0000000000000163

    View details for PubMedID 26125692

  • Pharmacokinetics of Prophylactic Cefazolin in Parturients Undergoing Cesarean Delivery (vol 58, pg 3504, 2014) ANTIMICROBIAL AGENTS AND CHEMOTHERAPY Elkomy, M. H., Sultan, P., Drover, D. R., Epshtein, E., Galinkin, J. L., Carvalho, B. 2015; 59 (6): 3694

    View details for PubMedID 25977453

  • Second-line uterotonics and the risk of hemorrhage-related morbidity. American journal of obstetrics and gynecology Butwick, A. J., Carvalho, B., Blumenfeld, Y. J., El-Sayed, Y. Y., Nelson, L. M., Bateman, B. T. 2015; 212 (5): 642 e1-7

    Abstract

    Uterine atony is a leading cause of postpartum hemorrhage (PPH). Although most cases of PPH respond to first line therapy with uterine massage and oxytocin administration, second line uterotonics including methylergonovine and carboprost are integral for the management of refractory uterine atony. Despite their ubiquitous use, it is uncertain whether the risk of hemorrhage-related morbidity differs in women exposed to methylergonovine or carboprost at Cesarean delivery (CD).We performed a secondary analysis using the Maternal-Fetal Medicine Units Network Cesarean Registry. We identified women who underwent CD and received either methylergonovine or carboprost for refractory uterine atony. The primary outcome was hemorrhage-related morbidity defined as intraoperative or postoperative red blood cells (RBC) transfusion or the need for additional surgical interventions including uterine artery ligation, hypogastric artery ligation, or peripartum hysterectomy for atony. We compared the risk of hemorrhage-related morbidity in those exposed to methylergonovine vs. carboprost. Propensity-score matching was used to account for potential confounders.The study cohort comprised 1,335 women; 870 (65.2%) women received methylergonovine and 465 (34.8%) women received carboprost. After accounting for potential confounders, the risk of hemorrhage-related morbidity was higher in the carboprost group than the methylergonovine group (RR = 1.7; 95% CI = 1.2 - 2.6).In this propensity-score matched analysis, methylergonovine was associated with reduced risk of hemorrhage-related morbidity during CD compared to carboprost. Based on these results, methylergonovine may be a more effective second line uterotonic.

    View details for DOI 10.1016/j.ajog.2015.01.008

    View details for PubMedID 25582104

  • Second-line uterotonics and the risk of hemorrhage-related morbidity AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY Butwick, A. J., Carvalho, B., Blumenfeld, Y. J., El-Sayed, Y. Y., Nelson, L. M., Bateman, B. T. 2015; 212 (5)

    Abstract

    Uterine atony is a leading cause of postpartum hemorrhage (PPH). Although most cases of PPH respond to first line therapy with uterine massage and oxytocin administration, second line uterotonics including methylergonovine and carboprost are integral for the management of refractory uterine atony. Despite their ubiquitous use, it is uncertain whether the risk of hemorrhage-related morbidity differs in women exposed to methylergonovine or carboprost at Cesarean delivery (CD).We performed a secondary analysis using the Maternal-Fetal Medicine Units Network Cesarean Registry. We identified women who underwent CD and received either methylergonovine or carboprost for refractory uterine atony. The primary outcome was hemorrhage-related morbidity defined as intraoperative or postoperative red blood cells (RBC) transfusion or the need for additional surgical interventions including uterine artery ligation, hypogastric artery ligation, or peripartum hysterectomy for atony. We compared the risk of hemorrhage-related morbidity in those exposed to methylergonovine vs. carboprost. Propensity-score matching was used to account for potential confounders.The study cohort comprised 1,335 women; 870 (65.2%) women received methylergonovine and 465 (34.8%) women received carboprost. After accounting for potential confounders, the risk of hemorrhage-related morbidity was higher in the carboprost group than the methylergonovine group (RR = 1.7; 95% CI = 1.2 - 2.6).In this propensity-score matched analysis, methylergonovine was associated with reduced risk of hemorrhage-related morbidity during CD compared to carboprost. Based on these results, methylergonovine may be a more effective second line uterotonic.

    View details for DOI 10.1016/j.ajog.2015.01.008

    View details for Web of Science ID 000353598500025

    View details for PubMedID 25582104

  • Norepinephrine for Spinal Hypotension during Cesarean Delivery: Another Paradigm Shift? Anesthesiology Carvalho, B., Dyer, R. A. 2015; 122 (4): 728-30

    View details for DOI 10.1097/ALN.0000000000000602

    View details for PubMedID 25654435

  • Magnesium sulfate exposure and neonatal intensive care unit admission at term. Journal of perinatology Girsen, A. I., Greenberg, M. B., El-Sayed, Y. Y., LEE, H., Carvalho, B., Lyell, D. J. 2015; 35 (3): 181-185

    Abstract

    Objective:The aim of this study was to investigate the effect of maternal magnesium sulfate (MgSO4) exposure for eclampsia prophylaxis on neonatal intensive care unit (NICU) admission rates for term newborns.Study Design:A secondary analysis of the Maternal-Fetal Medicine Unit Network Cesarean Registry, including primary and repeat cesarean deliveries, and failed and successful trials of labor after cesarean was conducted. Singleton pregnancies among women with preeclampsia and >37 weeks of gestation were included. Pregnancies with uterine rupture, chorioamnionitis and congenital malformations were excluded. Logistic regression analysis was used to determine associations between MgSO4 exposure and NICU admission. P<0.05 was considered statistically significant.Result:Two thousand one hundred and sixty-six term pregnancies of women with preeclampsia were included, of whom 1747 (81%) received MgSO4 for eclampsia prophylaxis and 419 (19%) did not. NICU admission rates were higher among newborns exposed to MgSO4 vs unexposed (22% vs 12%, P<0.001). After controlling for neonatal birth weight, gestational age and maternal demographic and obstetric factors, NICU admission remained significantly associated with antenatal MgSO4 exposure (adjusted odds ratio 1.9, 95% confidence interval 1.3 to 2.6, P<0.001). Newborns exposed to MgSO4 were more likely to have Apgar scores <7 at 1 and 5 min (15% vs 11% unexposed, P=0.01 and 3% vs 0.7% unexposed, P=0.008). There were no significant differences in NICU length of stay (median 5 (range 2 to 91) vs 6 (3 to 15), P=0.5).Conclusion:Antenatal maternal MgSO4 treatment was associated with increased NICU admission rates among exposed term newborns of mothers with preeclampsia. This study highlights the need for studies of maternal MgSO4 administration protocols that optimize maternal and fetal benefits and minimize risks.Journal of Perinatology advance online publication, 16 October 2014; doi:10.1038/jp.2014.184.

    View details for DOI 10.1038/jp.2014.184

    View details for PubMedID 25321647

  • Methylnaltrexone to prevent intrathecal morphine-induced pruritus after Caesarean delivery: a multicentre, randomized clinical trial. British journal of anaesthesia Paech, M., Sng, B., Ng, L., Nathan, E., Sia, A., Carvalho, B. 2015; 114 (3): 469-76

    Abstract

    Intrathecal morphine-induced pruritus is a very common side-effect that is difficult to prevent or treat. Central and peripheral mechanisms are believed to be involved. The aim of this study was to determine if a peripherally acting, μ-opioid antagonist would reduce morphine-induced pruritus.We conducted a multicentre, randomized, blinded, placebo-controlled trial of women having elective Caesarean section under spinal anaesthesia with intrathecal morphine 100 μg. After delivery, participants received either subcutaneous methylnatrexone bromide 12 mg (MNTX group, n=69) or saline (placebo group, n=68). Pruritus, nausea, pain, analgesic use, and side-effects were assessed at 2, 4, 8, and 24 h. The primary outcome was the severity of pruritus (0-10 score).One hundred and thirty-seven women completed the study, with five major protocol violations. There was no statistically significant difference between the MNTX and placebo groups for the median (IQR) pruritus AUC scores [24 (9-47) vs 36 (11-68), median difference 8.5, 95% confidence interval (CI) 0-20, P=0.09] or the worst pruritus score [3 (2-7) vs 5 (2-6), median difference 1, 95% CI 0-2, P=0.24]. The incidence of pruritus was 84% in the MNTX group and 88% in the placebo group (P=0.48). Analgesic and gastrointestinal outcomes did not significantly differ between the groups.A single dose of subcutaneous methylnaltrexone bromide 12 mg did not reduce the overall severity or incidence of pruritus. In this study, treatment with a peripherally acting μ-opioid antagonist was generally ineffective against intrathecal morphine-induced pruritus, but a small clinical effect cannot be excluded.Australian New Zealand Clinical Trials Registry (ACTRN12611000345987).

    View details for DOI 10.1093/bja/aeu410

    View details for PubMedID 25567476

  • Perioperative considerations of the patient with malaria CANADIAN JOURNAL OF ANESTHESIA-JOURNAL CANADIEN D ANESTHESIE Soltanifar, D., Carvalho, B., Sultan, P. 2015; 62 (3): 304-318

    Abstract

    Malaria is a life-threatening infectious disease caused by the Plasmodium parasite. Increased global travel has resulted in an escalation in the number of imported cases seen in developed countries. Patients with malaria may present for surgery in both endemic and non-endemic countries. This article reviews the perioperative considerations when managing patients with malaria.A literature review of anesthesia, perioperative care, and malaria-related articles was performed using the MEDLINE(®), EMBASE™, and Web of Science databases to identify relevant articles published in English during 1945-2014. Of the 303 articles matching the search criteria, 265 were excluded based on title and abstract. Eleven of the remaining 38 articles were relevant to anesthesia/perioperative care, and 27 articles were identified as having direct relevance to critical care medicine.The majority of imported malaria cases are caused by the falciparum species, which is associated with the greatest degree of morbidity and mortality. Various organ systems may be impacted as a consequence of changes in the structure and function of parasitized erythrocytes. Preoperative assessment should focus on establishing the species of malaria, the severity of disease, assessing the degree of end-organ impairment, and initiating treatment of malaria prior to surgery. Intravenous artesunate is the treatment of choice for severe falciparum malaria. Quinine is a second-line agent but has a narrow therapeutic index and particularly hazardous side effects. Intraoperatively, attention should focus on fluid management, dynamics of cerebral blood flow, and avoidance of hypoglycemia. Postoperative care of severe cases should ideally take place in a critical care unit as there may be ongoing requirements for multi-organ support, including renal replacement therapy, ventilation, and/or inotropic support. The safety of neuraxial anesthesia has not been well studied in the setting of malaria.Malaria remains one of the most devastating infectious diseases worldwide. Multiple organ systems can be impacted as a consequence of changes in structure and function of parasitized erythrocytes. Safe perioperative management requires a sound knowledge of all these potential system effects.

    View details for DOI 10.1007/s12630-014-0286-7

    View details for Web of Science ID 000349912900010

    View details for PubMedID 25471683

  • The impact of breastfeeding on postpartum pain after vaginal and cesarean delivery. Journal of clinical anesthesia Wen, L., Hilton, G., Carvalho, B. 2015; 27 (1): 33-38

    Abstract

    Oxytocin may play a role in pain modulation. The analgesic effects of breastfeeding with its associated endogenous oxytocin release have not been well investigated. To determine the impact of breastfeeding on incisional, perineal, and cramping pain after cesarean and vaginal delivery.Institutional review board-approved prospective observational study.Labor and delivery and maternity wards.Healthy (American Society of Anesthesiology physical statuses 1 and 2) multiparous women who had cesarean (n = 40) and vaginal (n = 43) deliveries of singleton term infants and who were breastfeeding were enrolled.Women completed diaries to record incisional, perineal, or cramping pain scores 5 minutes before, during, and 5 minutes after breastfeeding.Demographic, obstetric, and neonatal variables, as well as analgesic use, were recorded.There was no difference in incisional pain before, during, and after breastfeeding in women post-cesarean delivery. Cramping pain was significantly increased during, as compared with before or after breastfeeding in both the vaginal (P < .001) and cesarean (P < .001) delivery cohorts.There was no analgesic effect on incisional pain during breastfeeding, indicating that endogenous oxytocin associated with breastfeeding may not play a significant role in postpartum cesarean wound pain modulation. Breastfeeding increased cramping pain after vaginal and cesarean delivery. The increase in cramping pain is most likely due to the breastfeeding-associated oxytocin surge increasing uterine tone.

    View details for DOI 10.1016/j.jclinane.2014.06.010

    View details for PubMedID 25468582

  • Ondansetron pharmacokinetics in pregnant women and neonates: towards a new treatment for neonatal abstinence syndrome. Clinical pharmacology & therapeutics Elkomy, M., Sultan, P., Carvalho, B., Peltz, G., Wu, M., Clavijo, C., Galinkin, J., Drover, D. 2015; 97 (2): 167-176

    Abstract

    Ondansetron is the drug of choice to prevent nausea in women undergoing cesarean surgery and can be used to prevent neonatal abstinence syndrome (NAS). The pharmacokinetics of ondansetron have not been characterized in pregnant women or in newborns. A nonlinear mixed-effects modeling approach was used to analyze plasma samples obtained from 20 nonpregnant and 40 pregnant women following a single administration of 4 or 8 mg ondansetron, from umbilical cord blood at delivery, and from neonates after birth. The analysis indicates that: ondansetron disposition is not affected by pregnancy (P > 0.05), but influenced by dose (P < 0.05), and is characterized by rapid transplacental transfer and longer elimination half-life in neonates compared to their mother. A dosing regimen for prevention of NAS was designed based on the model. The regimen involves IV administration of 4 mg to the mothers shortly before cord clamping, or oral administration of 0.07 mg/kg (or equivalently 0.04 mg/kg IV) to neonates.

    View details for DOI 10.1002/cpt.5

    View details for PubMedID 25670522

    View details for PubMedCentralID PMC4325425

  • Drug labeling in the practice of obstetric anesthesia AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY Carvalho, B., Wong, C. A. 2015; 212 (1): 24-27

    Abstract

    This commentary outlines the current drug labeling practices that potentially compromise the clinical care of pregnant women and their children. We highlight the need for drug manufacturers and lawmakers to change the status quo and consider practices and regulations that will provide much-needed guidance to clinicians on the safe administration of drugs to certain populations such as pregnant and nursing women. Current practices have de facto contributed to a situation in which evidence is inadequate for individual physicians and patients to weigh the risks and benefits of drug administration and make informed decisions for drug use during pregnancy and lactation.

    View details for DOI 10.1016/j.ajog.2014.04.040

    View details for Web of Science ID 000346585700006

    View details for PubMedID 24799312

  • Survey of Accepted Practice following Failed Intubation for Emergency Caesarean Delivery. Anesthesiology research and practice Soltanifar, D., Bogod, D., Harrison, S., Carvalho, B., Sultan, P. 2015; 2015: 192315-?

    Abstract

    Background. There is no consensus on the optimum management of failed tracheal intubation in emergency cesarean delivery performed for fetal compromise. The decision making process on whether to wake the patient or continue anesthesia with a supraglottic airway device is an underexplored area. This survey explores perceptions and experiences of obstetric anesthetists managing failed intubation. Methods. Anesthetists attending the Group of Obstetric Anaesthetists London (GOAL) Meeting in April 2014 were surveyed. Results. Ninety-three percent of anesthetists surveyed would not always wake the patient in the event of failed intubation for emergency cesarean delivery performed for fetal compromise. The median (interquartile range) of perceived acceptability of continuing anesthesia with a well-fitting supraglottic airway device, assessed using a visual analogue scale (0-100; 0 completely unacceptable; 100 completely acceptable), was 90 [22.5]. Preoperative patient consent regarding the use of a supraglottic airway device for surgery in the event of failed intubation would affect the decision making of 40% of anaesthetists surveyed. Conclusion. These results demonstrate that a significant body of anesthetists with a subspecialty interest in obstetric anesthesia in the UK would not always wake up the patient and would continue with anesthesia and surgery with a supraglottic airway device in this setting.

    View details for DOI 10.1155/2015/192315

    View details for PubMedID 25821464

  • Elective ceasarean section at 38 weeks versus 39 weeks: neonatal and maternal outcomes in a randomised controlled trial reply BJOG-AN INTERNATIONAL JOURNAL OF OBSTETRICS AND GYNAECOLOGY Cho, Y., Carvalho, B., Butwick, A., Blumenfeld, Y., Riley, E. 2014; 121 (13): 1748-1749
  • Elective ceasarean section at 38 weeks versus 39 weeks: neonatal and maternal outcomes in a randomised controlled trial. BJOG : an international journal of obstetrics and gynaecology Cho, Y., Carvalho, B., Butwick, A., Blumenfeld, Y., Riley, E. 2014; 121 (13): 1748-?

    View details for DOI 10.1111/1471-0528.13079

    View details for PubMedID 25413764

  • Evaluation of a prospectively administered written questionnaire to reduce the incidence of suspected latex anaphylaxis during elective cesarean delivery INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Peer, L., BREZIS, M. L., Shalit, M., Carvalho, B., Levin, P. D., Seri, O., Weiniger, C. F. 2014; 23 (4): 335-340

    Abstract

    Life-threatening anaphylaxis has been reported in women exposed to latex during surgery. We compared a written screening questionnaire to identify suspected latex sensitivity with a verbal inquiry used previously in a historical control group of women undergoing cesarean delivery to determine if the incidence of suspected latex anaphylaxis could be reduced.To identify suspected latex sensitivity among women undergoing elective cesarean delivery in a single-site tertiary unit, a nine-item written screening questionnaire was compared to historical use of a standard verbal inquiry "Are you allergic to medications or latex?". Women who had suspected latex sensitivity risk factors, or who had known latex allergy, underwent latex-free surgery. Women with suspected anaphylaxis during cesarean delivery were recommended to undergo allergen testing. The primary study outcome was suspected anaphylaxis incidence during the two periods: historical control January to December 2008, questionnaire March 2010 to April 2011.The questionnaire identified suspected latex sensitivity in 66 of 453 women (14.6%) who completed the questionnaire. The standard verbal inquiry group had identified 12 of 460 women (2.6%) with self-reported latex sensitivity. The incidence of suspected anaphylaxis during cesarean delivery was significantly lower during the questionnaire period when compared to historical controls (3/516, 0.6% vs. 11/460, 2.4%, P=0.015). For both groups, 13 of 14 women (92.9%) with suspected latex anaphylaxis were contactable; five of 13 (38.5%) had undergone allergen testing and all were positive for latex.Use of the written screening questionnaire was associated with fewer cases of suspected anaphylaxis during cesarean delivery compared with the historical control. Most women with suspected anaphylaxis did not perform allergy testing; however, all who did were positive for latex.

    View details for DOI 10.1016/j.ijoa.2014.05.009

    View details for Web of Science ID 000345203200007

    View details for PubMedID 25201315

  • "Pseudo" Shearing of a Peripheral Nerve Catheter After Interscalene Block REGIONAL ANESTHESIA AND PAIN MEDICINE Carvalho, B., Derby, R., Horn, J. 2014; 39 (6): 556–57

    View details for PubMedID 25340485

  • Risk factors for obstetric morbidity in patients with uterine atony undergoing Caesarean delivery BRITISH JOURNAL OF ANAESTHESIA Butwick, A. J., Carvalho, B., El-Sayed, Y. Y. 2014; 113 (4): 661-668

    Abstract

    Uterine atony (UA) is recognized as a leading cause of postpartum haemorrhage. However, knowledge of risk factors of haemorrhage-related morbidity among patients diagnosed with UA is uncertain. We investigated risk factors for haemorrhage-related morbidity among patients undergoing Caesarean delivery with UA.We conducted a secondary analysis of data sourced from a 4-yr observational study at 19 US academic centres. Patients with UA were identified based on receiving methylergonovine or carboprost. Our primary outcome (haemorrhage-related morbidity) included a composite of intra- or postpartum transfusion; Caesarean hysterectomy; uterine or hypogastric artery ligation; intensive care admission for: pulmonary oedema, coagulopathy, adult respiratory distress syndrome, postoperative ventilation, or invasive line monitoring.Among 57 182 patients who underwent Caesarean delivery, 2294 (4%) patients developed UA. Haemorrhage-related morbidity occurred in 450 (19.6%) patients with UA. The risk of haemorrhage-related morbidity was increased among African-Americans [adjusted odds ratio (aOR)=2.36; 95% confidence interval (CI)=1.73-3.23], Hispanics (aOR=1.4; 95% CI=1.04-1.9), women with multiple gestations (aOR=1.59; 95% CI=1.06-2.38), placenta praevia (aOR=4.89; 95% CI=3.04-7.87), patients with ASA class III (aOR=1.4; 95 CI=1.03-1.9), or ASA class IV (aOR=5.88; 95% CI=2.48-13.9), exposure to general anaesthesia (GA) (aOR=2.4; 95% CI=1.59-3.62) and combined general and regional anaesthesia (aOR=4.0; 95% CI=2.62-6.09), and ≥2 prior Caesarean deliveries (aOR=1.62; 95% CI=1.1-2.39).Among patients with UA undergoing Caesarean delivery, the risk of haemorrhage-related morbidity is increased in African-Americans, Hispanics, patients with multiple gestations, placenta praevia, ASA class III or IV, ≥2 prior Caesarean deliveries and those undergoing GA.

    View details for DOI 10.1093/bja/aeu150

    View details for Web of Science ID 000343087400019

  • Risk factors for obstetric morbidity in patients with uterine atony undergoing caesarean delivery. British journal of anaesthesia Butwick, A. J., Carvalho, B., El-Sayed, Y. Y. 2014; 113 (4): 661-668

    Abstract

    Uterine atony (UA) is recognized as a leading cause of postpartum haemorrhage. However, knowledge of risk factors of haemorrhage-related morbidity among patients diagnosed with UA is uncertain. We investigated risk factors for haemorrhage-related morbidity among patients undergoing Caesarean delivery with UA.We conducted a secondary analysis of data sourced from a 4-yr observational study at 19 US academic centres. Patients with UA were identified based on receiving methylergonovine or carboprost. Our primary outcome (haemorrhage-related morbidity) included a composite of intra- or postpartum transfusion; Caesarean hysterectomy; uterine or hypogastric artery ligation; intensive care admission for: pulmonary oedema, coagulopathy, adult respiratory distress syndrome, postoperative ventilation, or invasive line monitoring.Among 57 182 patients who underwent Caesarean delivery, 2294 (4%) patients developed UA. Haemorrhage-related morbidity occurred in 450 (19.6%) patients with UA. The risk of haemorrhage-related morbidity was increased among African-Americans [adjusted odds ratio (aOR)=2.36; 95% confidence interval (CI)=1.73-3.23], Hispanics (aOR=1.4; 95% CI=1.04-1.9), women with multiple gestations (aOR=1.59; 95% CI=1.06-2.38), placenta praevia (aOR=4.89; 95% CI=3.04-7.87), patients with ASA class III (aOR=1.4; 95 CI=1.03-1.9), or ASA class IV (aOR=5.88; 95% CI=2.48-13.9), exposure to general anaesthesia (GA) (aOR=2.4; 95% CI=1.59-3.62) and combined general and regional anaesthesia (aOR=4.0; 95% CI=2.62-6.09), and ≥2 prior Caesarean deliveries (aOR=1.62; 95% CI=1.1-2.39).Among patients with UA undergoing Caesarean delivery, the risk of haemorrhage-related morbidity is increased in African-Americans, Hispanics, patients with multiple gestations, placenta praevia, ASA class III or IV, ≥2 prior Caesarean deliveries and those undergoing GA.

    View details for DOI 10.1093/bja/aeu150

    View details for PubMedID 24907281

  • The dilemma of vaginal breech delivery worldwide. Lancet Weiniger, C. F., Carvalho, B. 2014; 384 (9949): 1183-?

    View details for DOI 10.1016/S0140-6736(14)61718-9

    View details for PubMedID 25263673

  • A prospective observational study evaluating the ability of prelabor psychological tests to predict labor pain, epidural analgesic consumption, and maternal satisfaction. Anesthesia and analgesia Carvalho, B., Zheng, M., Aiono-Le Tagaloa, L. 2014; 119 (3): 632-640

    Abstract

    Psychological characteristics may affect interpretation and expression of pain. In this study, we sought to determine whether validated psychological tests predict the labor pain experience.Thirty-nine women with singleton term or post-term pregnancies undergoing induction of labor and successful vaginal delivery comprised the study population for this prospective observational study. Four validated psychological questionnaires (Anxiety Sensitivity Index [ASI], Fear of Pain [FPQIII], Pain Catastrophizing Scale [PCS]), and Eysenck Personality Questionnaire-Short Scale) and 3-scaled ratings of anxiety, confidence, and analgesic expectations were completed before onset of labor. Outcome measures included time to epidural analgesia request, pain at request for epidural analgesia, area under the pain × time curve (AUC), epidural local anesthetic use per hour, and maternal satisfaction with analgesia. The relationship between psychological predictors and clinical responses was assessed using bivariate correlations and regression modeling.Labor pain AUC (R = 0.45, P = 0.006), epidural local anesthetic use (R = 0.45, P = 0.019), and time to epidural analgesia request (R = 0.36, P = 0.015) were predicted with models incorporating some of the prelabor predictors. ASI, PCS, personality traits (lying, extroversion, psychoticism), and scaled ratings of anxiety, confidence, and analgesic expectations all contributed to the regression models of the outcomes. After proper model selection, neither FPQIII nor PCS was in the final multivariate linear regression model for labor pain AUC, although ASI was still included (P = 0.022). There was no significant correlation between ASI and self-reported anxiety (r = 0.03, P = 0.91).Personality traits (psychoticism, extroversion, and lying), as well as scaled ratings of anxiety, confidence, and analgesia expectations, show some potential to predict labor pain, epidural local anesthetic use, and time to epidural analgesia request. Although ASI was included in the final model for labor pain AUC, and FPQ and PCS were not, further study is required to determine whether ASI is a better predictor than FPQ or PCS.

    View details for DOI 10.1213/ANE.0000000000000357

    View details for PubMedID 25029661

  • In reply. journal of hand surgery Carvalho, B., Ahsan, Z. S., Yao, J. 2014; 39 (9): 1888-1889

    View details for DOI 10.1016/j.jhsa.2014.06.124

    View details for PubMedID 25154582

  • Prospective longitudinal cohort questionnaire assessment of labouring women's preference both pre- and post-delivery for either reduced pain intensity for a longer duration or greater pain intensity for a shorter duration. British journal of anaesthesia Carvalho, B., Hilton, G., Wen, L., Weiniger, C. F. 2014; 113 (3): 468-473

    Abstract

    Assessments of labour pain focus on pain intensity, not on duration. We aimed to assess the importance labouring women apply to pain intensity and duration before labour and post-delivery.Forty healthy women scheduled for labour induction were enrolled in this institutional review board-approved, prospective cohort study. Participants completed a pain preference questionnaire before active labour and within 24-h of delivery. The questionnaire consisted of seven stem questions that evaluated preference for pain intensity or duration. The pain preference ratio was determined by dividing the percentage of women who preferred reduced pain intensity for longer duration by that of those who preferred greater pain intensity for shorter duration (estimate of the odds). The overall hypothetical pain burden was determined by multiplying intensity by time. All questions presented the same overall hypothetical pain burden.Pain preference questionnaire scores demonstrated preference for low intensity pain for a longer duration rather than higher intensity for a shorter duration, both pre-labour (P<0.001) and post-delivery (P<0.001): the null median imputed as 3 of 6 (i.e. no preference for pain intensity over pain duration). This preference for pain duration over intensity was greater post-delivery compared with before labour (P=0.03). There was a significant correlation (r=0.83; P=0.04) between the pain preference ratio vs overall hypothetical pain burden before labour but not after delivery (r=0.28; P=0.59).In this preliminary labour assessment, women preferred lower pain intensity at the cost of longer pain duration. This suggests that pain intensity is the primary driver of hypothetical pain burden-a preference reinforced post-delivery.

    View details for DOI 10.1093/bja/aeu149

    View details for PubMedID 24907280

  • Pharmacokinetics of prophylactic cefazolin in parturients undergoing cesarean delivery. Antimicrobial agents and chemotherapy Elkomy, M. H., Sultan, P., Drover, D. R., Epshtein, E., Galinkin, J. L., Carvalho, B. 2014; 58 (6): 3504-3513

    Abstract

    The objectives of this work were (i) to characterize the pharmacokinetics of cefazolin in pregnant women undergoing elective cesarean delivery and in their neonates; (ii) to assess cefazolin transplacental transmission; (iii) to evaluate the dosing and timing of preoperative, prophylactic administration of cefazolin to pregnant women; and (iv) to investigate the impact of maternal dosing on therapeutic duration and exposure in newborns. Twenty women received 1 g of cefazolin preoperatively. Plasma concentrations of total cefazolin were analyzed from maternal blood samples taken before, during, and after delivery; umbilical cord blood samples obtained at delivery; and neonatal blood samples collected 24 h after birth. The distribution volume of cefazolin was 9.44 liters/h. The values for pre- and postdelivery clearance were 7.18 and 4.12 liters/h, respectively. Computer simulations revealed that the probability of maintaining free cefazolin concentrations in plasma above 8 mg/liter during scheduled caesarean surgery was <50% in the cord blood when cefazolin was administered in doses of <2 g or when it was administered <1 h before delivery. Therapeutic concentrations of cefazolin persisted in neonates >5 h after birth. Cefazolin clearance increases during pregnancy, and larger doses are recommended for surgical prophylaxis in pregnant women to obtain the same antibacterial effect as in nonpregnant patients. Cefazolin has a longer half-life in neonates than in adults. Maternal administration of up to 2 g of cefazolin is effective and produces exposure within clinically approved limits in neonates.

    View details for DOI 10.1128/AAC.02613-13

    View details for PubMedID 24733461

  • Pharmacokinetics of Prophylactic Cefazolin in Parturients Undergoing Cesarean Delivery ANTIMICROBIAL AGENTS AND CHEMOTHERAPY Elkomy, M. H., Sultan, P., Drover, D. R., Epshtein, E., Galinkin, J. L., Carvalho, B. 2014; 58 (6): 3504-3513

    Abstract

    The objectives of this work were (i) to characterize the pharmacokinetics of cefazolin in pregnant women undergoing elective cesarean delivery and in their neonates; (ii) to assess cefazolin transplacental transmission; (iii) to evaluate the dosing and timing of preoperative, prophylactic administration of cefazolin to pregnant women; and (iv) to investigate the impact of maternal dosing on therapeutic duration and exposure in newborns. Twenty women received 1 g of cefazolin preoperatively. Plasma concentrations of total cefazolin were analyzed from maternal blood samples taken before, during, and after delivery; umbilical cord blood samples obtained at delivery; and neonatal blood samples collected 24 h after birth. The distribution volume of cefazolin was 9.44 liters/h. The values for pre- and postdelivery clearance were 7.18 and 4.12 liters/h, respectively. Computer simulations revealed that the probability of maintaining free cefazolin concentrations in plasma above 8 mg/liter during scheduled caesarean surgery was <50% in the cord blood when cefazolin was administered in doses of <2 g or when it was administered <1 h before delivery. Therapeutic concentrations of cefazolin persisted in neonates >5 h after birth. Cefazolin clearance increases during pregnancy, and larger doses are recommended for surgical prophylaxis in pregnant women to obtain the same antibacterial effect as in nonpregnant patients. Cefazolin has a longer half-life in neonates than in adults. Maternal administration of up to 2 g of cefazolin is effective and produces exposure within clinically approved limits in neonates.

    View details for DOI 10.1128/AAC.02613-13

    View details for Web of Science ID 000338776900064

  • Preferred spoken language mediates differences in neuraxial labor analgesia utilization among racial and ethnic groups. International journal of obstetric anesthesia Caballero, J. A., Butwick, A. J., Carvalho, B., Riley, E. T. 2014; 23 (2): 161-167

    Abstract

    The aims of this study were to assess racial/ethnic disparities for neuraxial labor analgesia utilization and to determine if preferred spoken language mediates the association between race/ethnicity and neuraxial labor analgesia utilization.We performed a retrospective cohort study of 3129 obstetric patients who underwent vaginal delivery at a tertiary care obstetric center. Bivariate analyses and multivariate logistic regression models were used to assess the relationships between race/ethnicity, preferred spoken language and neuraxial labor analgesia.Hispanic ethnicity (adjusted OR 0.77, 95% CI 0.61-0.98) and multiparity (adjusted OR 0.59, 95% CI 0.51-0.69) were independently associated with a reduced likelihood of neuraxial labor analgesia utilization. When preferred spoken language was controlled for, the effect of Hispanic ethnicity was no longer significant (adjusted OR 0.84, 95% CI 0.66-1.08) and only non-English preferred spoken language (adjusted OR 0.82, 95% CI 0.67-0.99) and multiparity (adjusted OR 0.59, 95% CI 0.51-0.69) were associated with a reduced likelihood of neuraxial labor analgesia utilization.This study provides evidence that preferred spoken language mediates the relationship between Hispanic ethnicity and neuraxial labor analgesia utilization.

    View details for DOI 10.1016/j.ijoa.2013.09.001

    View details for PubMedID 24703871

  • Application of Echogenic Technology for Catheters Used in Ultrasound-Guided Continuous Peripheral Nerve Blocks JOURNAL OF ULTRASOUND IN MEDICINE Mariano, E. R., Yun, R. D., Kim, T. E., Carvalho, B. 2014; 33 (5): 905-911

    Abstract

    Limited data exist regarding the echogenicity of perineural catheters, but visualization is crucial to ensure accurate placement and efficacy of the subsequent local anesthetic infusion. The objective of this study was to determine the comparative echogenicity of various regional anesthesia catheters. In an in vitro porcine-bovine model, we compared the echogenic qualities of 3 commercially available regional anesthesia catheters and 1 catheter under development to optimize echogenicity. Outcomes included visual echogenicity ranking, image quality, and scanning time, as assessed by 2 blinded investigators. The experimental catheter was found to be more echogenic than 2 of the 3 comparators.

    View details for DOI 10.7863/ultra.33.5.905

    View details for Web of Science ID 000335620700018

    View details for PubMedID 24764346

  • The society for obstetric anesthesia and perinatology consensus statement on the management of cardiac arrest in pregnancy. Anesthesia and analgesia Lipman, S., Cohen, S., Einav, S., Jeejeebhoy, F., Mhyre, J. M., Morrison, L. J., Katz, V., Tsen, L. C., Daniels, K., Halamek, L. P., Suresh, M. S., Arafeh, J., Gauthier, D., Carvalho, J. C., Druzin, M., Carvalho, B. 2014; 118 (5): 1003-1016

    Abstract

    This consensus statement was commissioned in 2012 by the Board of Directors of the Society for Obstetric Anesthesia and Perinatology to improve maternal resuscitation by providing health care providers critical information (including point-of-care checklists) and operational strategies relevant to maternal cardiac arrest. The recommendations in this statement were designed to address the challenges of an actual event by emphasizing health care provider education, behavioral/communication strategies, latent systems errors, and periodic testing of performance. This statement also expands on, interprets, and discusses controversial aspects of material covered in the American Heart Association 2010 guidelines.

    View details for DOI 10.1213/ANE.0000000000000171

    View details for PubMedID 24781570

  • In response. Anesthesia and analgesia Macario, A., Carvalho, B., Tan, J. M., Sultan, P., El-Sayed, Y. Y. 2014; 118 (4): 884-885

    View details for DOI 10.1213/ANE.0000000000000114

    View details for PubMedID 24651247

  • Analgesia following cesarean delivery: "Sometimes it takes a painful experience to make us change our ways" (proverbs 20:30). Israel Medical Association journal Weiniger, C. F., Carvalho, B. 2014; 16 (3): 171-172

    View details for PubMedID 24761706

  • Incidence of Failure of Continuous Peripheral Nerve Catheters for Postoperative Analgesia in Upper Extremity Surgery. journal of hand surgery Ahsan, Z. S., Carvalho, B., Yao, J. 2014; 39 (2): 324-329

    Abstract

    To explore the incidence of failure of continuous peripheral nerve blockade (CPNB) after upper extremity operations.Patient data regarding postoperative CPNB were retrospectively obtained from our institution's regional anesthesia database. Documented information on the first postoperative day included pain assessment ratings (numerical verbal pain scale, patient-reported breakthrough pain upon perceived return of sensation, appearance of the catheter site, complications, time of return of sensation, day of return of sensation, residual blockade, patient satisfaction with the block, and whether patient would receive the block again).A total of 207 patients received CPNB for postoperative analgesia. The failure rate on the first postoperative day for infraclavicular (133 patients) and supraclavicular (58 patients) CPNB was 19% and 26%, respectively. Interscalene CPNB (16 patients) yielded 3 incidences of failure. No significant difference was found between supraclavicular and infraclavicular block techniques. In addition, no significant differences were found between the incidences of CPNB failures with potentially more painful surgeries involving bone compared with potentially less painful soft tissue procedures.The CPNB technique used for hand surgery postoperative analgesia was associated with nontrivial failure rates. The potential of CPNB failure and resulting breakthrough pain upon recovery from the primary nerve block is important to help establish patient expectations.Therapeutic IV.

    View details for DOI 10.1016/j.jhsa.2013.11.011

    View details for PubMedID 24480691

  • Preventing spinal hypotension during Caesarean delivery: what is the latest? British journal of anaesthesia Butwick, A. J., Columb, M. O., Carvalho, B. n. 2014

    View details for PubMedID 25080429

  • Temporal stability of conditioned pain modulation in healthy women over four menstrual cycles at the follicular and luteal phases PAIN Wilson, H., Carvalho, B., Granot, M., Landau, R. 2013; 154 (12): 2633-2638

    Abstract

    Conditioned pain modulation (CPM) is a phenomenon that may be tested with a dynamic quantitative sensory test that assesses the inhibitory aspect of this pain modulatory network. Although CPM has been adopted as a clinical assessment tool in recent years, the stability of the measure has not been determined over long time intervals. The question of stability over time is crucial to our understanding of pain processing, and critical for the use of this tool as a clinical test. The primary objective of this study was to evaluate the stability of a CPM paradigm over time in healthy women. The secondary objective was to determine the potential influence of menstrual cycle phase on CPM. CPM was assessed 8 times in 22 healthy women during the follicular and luteal phases of 4 different cycles. The CPM effect was evidenced by a reduction in the pain rating of a test stimulus (6.3±0.2) with the introduction of a conditioning stimulus (5.0±0.3; P<0.001). The intraclass correlation coefficient for the CPM effect was modest (0.39; CI=0.23-0.59), suggesting that there is significant variation in CPM over long time intervals. CPM did not vary across phases in the menstrual cycle. Prior to the adoption of CPM as a clinical tool to predict individual risk and aid diagnosis, additional research is needed to establish the measurement properties of CPM paradigms and evaluate factors that influence CPM effects.

    View details for DOI 10.1016/j.pain.2013.06.038

    View details for Web of Science ID 000327596200011

    View details for PubMedID 23811040

  • The effect of low concentrations versus high concentrations of local anesthetics for labour analgesia on obstetric and anesthetic outcomes: a meta-analysis CANADIAN JOURNAL OF ANESTHESIA-JOURNAL CANADIEN D ANESTHESIE Sultan, P., Murphy, C., Halpern, S., Carvalho, B. 2013; 60 (9): 840-854

    Abstract

    The influence that different concentrations of labour epidural local anesthetic have on assisted vaginal delivery (AVD) and many obstetric outcomes and side effects is uncertain. The purpose of this meta-analysis was to determine whether local anesthetics utilized at low concentrations (LCs) during labour are associated with a decreased incidence of AVD when compared with high concentrations (HCs).We searched PubMed, Ovid EMBASE, Ovid MEDLINE, CINAHL, Scopus, clinicaltrials.gov, and Cochrane databases for randomized controlled trials of labouring patients that compared LCs (defined as ≤ 0.1% epidural bupivacaine or ≤ 0.17% ropivacaine) of epidural local anesthetic with HCs for maintenance of analgesia. The primary outcome was AVD and secondary outcomes included Cesarean delivery, duration of labour, analgesia, side effects (nausea and vomiting, motor block, hypotension, pruritus, and urinary retention), and neonatal outcomes. The odds ratios (OR) or weighted mean differences (WMD) and 95% confidence intervals (CI) were calculated using random effects modelling. An OR < 1 or a WMD < 0 favoured LCs.Eleven studies met our criteria (eight bupivacaine and three ropivacaine studies), providing 1,145 patients in the LCs group and 852 patients in the HCs group for analysis of the primary outcome. Low concentrations were associated with a reduction in the incidence of AVD (OR = 0.70; 95% CI 0.56 to 0.86; P < 0.001). There was no difference in the incidence of Cesarean delivery (OR 1.05; 95% CI 0.82 to 1.33; P = 0.7). The LCs group had less motor block (OR 3.9; 95% CI 1.59 to 9.55; P = 0.003), greater ambulation (OR 2.8; 95% CI 1.1 to 7.14; P = 0.03), less urinary retention (OR 0.42; 95% CI 0.23 to 0.73; P = 0.002), and a shorter second stage of labour (WMD -14.03; 95% CI -27.52 to -0.55; P = 0.04) compared with the HCs group. There were no differences between groups in pain scores, maternal nausea and vomiting, hypotension, fetal heart rate abnormalities, five-minute Apgar scores, and need for neonatal resuscitation. One-minute Apgar scores < 7 favoured the HCs group (OR 1.53; 95% CI 1.07 to 2.21; P = 0.02), and there was more pruritus in the LCs group (OR 3.36; 95% CI 1.00 to 11.31; P = 0.05).When compared with HCs of local anesthetics, the use of LCs for labour epidural analgesia reduces the incidence of AVD. This may be due to a reduction in the amount of local anesthetic used and the subsequent decrease in motor blockade. We therefore recommend the use of LCs of local anesthetics for epidural analgesia to optimize obstetric outcome.

    View details for DOI 10.1007/s12630-013-9981-z

    View details for Web of Science ID 000323340700002

    View details for PubMedID 23925722

  • Brief report: a cost analysis of neuraxial anesthesia to facilitate external cephalic version for breech fetal presentation. Anesthesia and analgesia Carvalho, B., Tan, J. M., Macario, A., El-Sayed, Y. Y., Sultan, P. 2013; 117 (1): 155-159

    Abstract

    BACKGROUND:In this study, we sought to determine whether neuraxial anesthesia to facilitate external cephalic version (ECV) increased delivery costs for breech fetal presentation.METHODS:Using a computer cost model, which considers possible outcomes and probability uncertainties at the same time, we estimated total expected delivery costs for breech presentation managed by a trial of ECV with and without neuraxial anesthesia.RESULTS:From published studies, the average probability of successful ECV with neuraxial anesthesia was 60% (with individual studies ranging from 44% to 87%) compared with 38% (with individual studies ranging from 31% to 58%) without neuraxial anesthesia. The mean expected total delivery costs, including the cost of attempting/performing ECV with anesthesia, equaled $8931 (2.5th-97.5th percentile prediction interval $8541-$9252). The cost was $9207 (2.5th-97.5th percentile prediction interval $8896-$9419) if ECV was attempted/performed without anesthesia. The expected mean incremental difference between the total cost of delivery that includes ECV with anesthesia and ECV without anesthesia was $-276 (2.5th-97.5th percentile prediction interval $-720 to $112).CONCLUSION:The total cost of delivery in women with breech presentation may be decreased (up to $720) or increased (up to $112) if ECV is attempted/performed with neuraxial anesthesia compared with ECV without neuraxial anesthesia. Increased ECV success with neuraxial anesthesia and the subsequent reduction in breech cesarean delivery rate offset the costs of providing anesthesia to facilitate ECV.

    View details for DOI 10.1213/ANE.0b013e31828e5bc7

    View details for PubMedID 23592608

  • A Cost Analysis of Neuraxial Anesthesia to Facilitate External Cephalic Version for Breech Fetal Presentation ANESTHESIA AND ANALGESIA Carvalho, B., Tan, J. M., Macario, A., El-Sayed, Y. Y., Sultan, P. 2013; 117 (1): 155-159

    Abstract

    BACKGROUND:In this study, we sought to determine whether neuraxial anesthesia to facilitate external cephalic version (ECV) increased delivery costs for breech fetal presentation.METHODS:Using a computer cost model, which considers possible outcomes and probability uncertainties at the same time, we estimated total expected delivery costs for breech presentation managed by a trial of ECV with and without neuraxial anesthesia.RESULTS:From published studies, the average probability of successful ECV with neuraxial anesthesia was 60% (with individual studies ranging from 44% to 87%) compared with 38% (with individual studies ranging from 31% to 58%) without neuraxial anesthesia. The mean expected total delivery costs, including the cost of attempting/performing ECV with anesthesia, equaled $8931 (2.5th-97.5th percentile prediction interval $8541-$9252). The cost was $9207 (2.5th-97.5th percentile prediction interval $8896-$9419) if ECV was attempted/performed without anesthesia. The expected mean incremental difference between the total cost of delivery that includes ECV with anesthesia and ECV without anesthesia was $-276 (2.5th-97.5th percentile prediction interval $-720 to $112).CONCLUSION:The total cost of delivery in women with breech presentation may be decreased (up to $720) or increased (up to $112) if ECV is attempted/performed with neuraxial anesthesia compared with ECV without neuraxial anesthesia. Increased ECV success with neuraxial anesthesia and the subsequent reduction in breech cesarean delivery rate offset the costs of providing anesthesia to facilitate ECV.

    View details for DOI 10.1213/ANE.0b013e31828e5bc7

    View details for Web of Science ID 000326512300025

  • Response times for emergency cesarean delivery: use of simulation drills to assess and improve obstetric team performance JOURNAL OF PERINATOLOGY Lipman, S. S., Carvalho, B., Cohen, S. E., Druzin, M. L., Daniels, K. 2013; 33 (4): 259-263

    Abstract

    We documented time to key milestones and determined reasons for transport-related delays during simulated emergency cesarean.Prospective, observational investigation of delivery of care processes by multidisciplinary teams of obstetric providers on the labor and delivery unit at Lucile Packard Children's Hospital, Stanford, CA, USA, during 14 simulated uterine rupture scenarios. The primary outcome measure was the total time from recognition of the emergency (time zero) to that of surgical incision.The median (interquartile range) from time zero until incision was 9 min 27 s (8:55 to 10:27 min:s).In this series of emergency cesarean drills, our teams required approximately nine and a half minutes to move from the labor room to the nearby operating room (OR) and make the surgical incision. Multiple barriers to efficient transport were identified. This study demonstrates the utility of simulation to identify and correct institution-specific barriers that delay transport to the OR and initiation of emergency cesarean delivery.

    View details for DOI 10.1038/jp.2012.98

    View details for Web of Science ID 000316833300002

    View details for PubMedID 22858890

  • Evaluation of experimental pain tests to predict labour pain and epidural analgesic consumption BRITISH JOURNAL OF ANAESTHESIA Carvalho, B., Zheng, M., Aiono-Le Tagaloa, L. 2013; 110 (4): 600-606

    Abstract

    The aim of this study was to determine whether experimental pain tests (EPTs) using heat, pressure, and i.v. cannulation before induction of labour reliably predict epidural analgesic use and pain intensity during labour.Fifty healthy women with singleton, term pregnancies admitted for scheduled induction of labour comprised the study population for this prospective case-controlled study. Heat and pressure threshold, tolerance, and suprathreshold VAS pain ratings were determined using a Medoc thermal sensory analyser and Somedic pressure algometer, respectively, after admission before induction of labour. Verbal pain scores (VPS 0-10) were determined during peripheral 18 G i.v. placement. Response outcomes included time to epidural request, pain at epidural, labour pain [area under the curve (AUC) and worse score], and epidural local anaesthetic use. Bivariate analysis followed by forward-backward multiple regression modelling was performed to determine relationships between EPTs and labour pain response measures.Heat tolerance was significantly correlated with worst labour pain (r=0.33, P=0.025) and pain with i.v. cannulation was correlated with time to epidural request (r=0.33, P=0.025). Multiple linear regression analysis found that labour pain AUC could be predicted with suprathreshold heat VAS, heat tolerance, and pressure tolerance (R(2)=0.26; P=0.007). There were strong correlations among the various pre-labour QSTs.Pre-labour EPTs were not very reliable at predicting the labour pain experience. Consistent with postoperative studies, suprathreshold and tolerance tests appear more useful than the threshold for predicting labour pain responses. Pain rating during i.v. cannulation (an easy, rapid, point-of-care test) showed some utility as an EPT.

    View details for DOI 10.1093/bja/aes423

    View details for Web of Science ID 000316700600015

    View details for PubMedID 23188095

  • Transversus abdominis plane blocks for rescue analgesia following Cesarean delivery: a case series CANADIAN JOURNAL OF ANESTHESIA-JOURNAL CANADIEN D ANESTHESIE Mirza, F., Carvalho, B. 2013; 60 (3): 299-303

    Abstract

    The role of routine transversus abdominis plane (TAP) blocks at the time of surgery for Cesarean delivery analgesia is uncertain. Previous studies have shown no additional analgesic benefit in patients receiving intrathecal morphine. We present a series of three cases where TAP blocks were used for rescue analgesia in patients who had severe post-Cesarean delivery pain after a standard spinal anesthetic containing bupivacaine 12 mg, fentanyl 10 μg, and morphine 200 μg.All three women experienced severe incisional pain in the postanesthetic care unit (PACU) after offset of spinal anesthesia. When the pain did not subside with intravenous opioids, the women were offered either additional intravenous opioids or a TAP block. They chose the latter. Bilateral TAP blocks were performed in a sterile posterior approach under ultrasound guidance with 0.375% ropivacaine 20 mL with epinephrine 1:400,000. All three patients experienced significant pain relief that lasted 10-19 hr and allowed for a timely discharge from the PACU.These cases show that TAP blocks may play a valuable role as a rescue analgesic technique rather than as a routine preemptive block for all Cesarean delivery patients. Use of TAP blocks reduced the need for escalating intravenous opioid doses and potential maternal opioid-related side effects. Rescue TAP blocks should be considered after Cesarean delivery when intrathecal morphine does not provide adequate pain relief or for early breakthrough pain after offset of spinal anesthesia.

    View details for DOI 10.1007/s12630-012-9866-6

    View details for Web of Science ID 000315578700011

    View details for PubMedID 23263981

  • The Effect of OPRM1 and COMT Genotypes on the Analgesic Response to Intravenous Fentanyl Labor Analgesia ANESTHESIA AND ANALGESIA Landau, R., Liu, S., Blouin, J., Carvalho, B. 2013; 116 (2): 386-391

    Abstract

    IV fentanyl is used as a labor analgesic; however, few studies have reported the effects of IV fentanyl for early labor analgesia. We evaluated the analgesic response to IV fentanyl according to the combined effect of the single-nucleotide polymorphisms rs1799971 (c.118A/G, p. 40Asn/Asp) of the µ-opioid receptor gene (OPRM1) and rs4680 (c.472G/A, p.158Val/Met) of the catechol-O-methyltransferase (COMT) gene in women requesting labor analgesia.Labor analgesia was initiated with IV fentanyl 1.5 μg/kg. The primary outcome was analgesic success, defined as Numerical Verbal Pain Scale score≤10/100 15 minutes after the dose of fentanyl. Analgesic and side effect outcomes were compared according to OPRM1 and COMT genotypes.One hundred six women were enrolled and received IV fentanyl. IV analgesic success was 6% in women with the combination Asn/Asn-Met/Met (n=17) versus 20% in all other women combined (not Asn/Asn-Met/Met; P=0.30; difference=14%; 95% confidence interval [CI], -10% to 26%). IV analgesic success was 20% in women 118A/A (Asn/Asn) versus 21% for A/G and G/G of OPRM1 (P=0.82; difference=2%; 95% CI, -17% to 19%), and 10% in women 472A (Met/Met) versus 22% for A/G (Met/Val) and G/G (Val/Val) of COMT (P=0.24; difference=12%; 95% CI, -6% to 26%). Met/Met158 (n=31) versus Met/Val or Val/Val of COMT was associated with a smaller decrease in Numerical Verbal Pain Scale (24±18 vs 37±23; P=0.005; mean difference=-13; 99% CI, -25 to -1).This study was underpowered to draw firm conclusions on the influence of OPRM1 and COMT genotypes on labor analgesia with IV fentanyl. Further larger studies are needed to evaluate whether genotyping COMT alone or in combination with OPRM1 may have potentially useful clinical implications, such as not offering IV fentanyl in early labor to women who will most likely not benefit from it.

    View details for DOI 10.1213/ANE.0b013e318273f2c7

    View details for Web of Science ID 000314078300019

    View details for PubMedID 23302985

  • Postoperative Subcutaneous Instillation of Low-Dose Ketorolac But Not Hydromorphone Reduces Wound Exudate Concentrations of Interleukin-6 and Interleukin-10 and Improves Analgesia Following Cesarean Delivery JOURNAL OF PAIN Carvalho, B., Lemmens, H. J., Ting, V., Angst, M. S. 2013; 14 (1): 48-56

    Abstract

    The objectives of this study were to test the effects of low-dose ketorolac and hydromorphone added to continuous local anesthetic wound instillation on surgical-site inflammatory mediators, postoperative pain, and opioid consumption. Sixty healthy women undergoing cesarean delivery were enrolled in this randomized, double-blinded study. Patients were randomized to receive a subcutaneous wound instillation of bupivacaine .5% at 10 mg/hour (active control), bupivacaine .5% with ketorolac .6 mg/hour, or bupivacaine .5% with hydromorphone .04 mg/hour for 48 hours postcesarean. Wound exudate was sampled at 4, 24, and 48 hours postcesarean and assayed for interleukins IL-1β, IL-2, IL-6, IL-8, IL-10, and IL-12, tumor necrosis factor (TNF-α), interferon (INF-γ), and granulocyte-macrophage colony stimulating factor (GM-CSF). The addition of ketorolac to bupivacaine significantly decreased IL-6 (P = .012) and IL-10 (P = .005) compared to plain bupivacaine. Ketorolac, but not hydromorphone, was associated with a decrease in pain (P = .018) and analgesic use (P = .020) following cesarean delivery. Our results are compatible with the view that significant analgesics effects are mediated through local modulation of inflammatory events. Low-dose ketorolac administered into surgical wounds exert significant anti-inflammatory and analgesic effects and may be a valuable analgesic alternative to systemic nonsteroidal anti-inflammatories (NSAIDs) but with potentially fewer side effects.This article demonstrates that low-dose ketorolac administered into wounds modulates local inflammatory events, decreases postoperative pain, and reduces opioid consumption. These results suggest that administration of NSAIDs into surgical wounds may be an analgesic alternative to higher systemic dosing of NSAIDs.

    View details for DOI 10.1016/j.jpain.2012.10.002

    View details for PubMedID 23218935

  • Transport Decreases the Quality of Cardiopulmonary Resuscitation During Simulated Maternal Cardiac Arrest ANESTHESIA AND ANALGESIA Lipman, S. S., Wong, J. Y., Arafeh, J., Cohen, S. E., Carvalho, B. 2013; 116 (1): 162-167

    Abstract

    The purpose of this study was to compare cardiopulmonary resuscitation (CPR) for simulated maternal cardiac arrest rendered during transport to the operating room with that rendered while stationary in the labor room. We hypothesized that the quality of CPR would deteriorate during transport.Twenty-six teams composed of 2 providers (obstetricians, nurses, or anesthesiologists) were randomized to perform CPR on the Laerdal Resusci Anne SkillReporter™ mannequin during transport or while stationary. The primary outcome measure was the percentage of correctly delivered compressions, defined as compression rate ≥100 beats per minute, correct sternal hand placement, compression depth ≥1.5 inches (3.8 cm), and proper release. Secondary outcomes included interruptions in compressions, position of providers relative to the mannequin during the transport phase, and ventilation tidal volume.The median (interquartile range) percentage of correctly rendered compressions during phase II was 32% (10%-63%) in the transport group and 93% (58%-100%) in the stationary group (P = 0.002, 95% confidence interval of mean difference = 22%-58%). The median (interquartile range) compression rates were 124 (110-140) beats per minute in the transport group and 123 (115-132) beats per minute in the stationary group (P = 0.531). Interruptions in CPR were observed in 92% of transport and 7% of stationary drills (P < 0.001, 95% confidence interval of difference = 61%-92%). During transport, 18 providers kneeled next to the mannequin, 2 straddled the mannequin, and 4 ran alongside the gurney. Median (interquartile range) tidal volume was 270 (166-430) mL in the transport group and 390 (232-513) mL in the stationary group (P = 0.03).Our data confirm our hypothesis and demonstrate that transport negatively affects the overall quality of resuscitation on a mannequin during simulated maternal arrest. These findings, together with previously published data on transport-related delays when moving from the labor room to the operating room further strengthen recommendations that perimortem cesarean delivery should be performed at the site of maternal cardiac arrest.

    View details for DOI 10.1213/ANE.0b013e31826dd889

    View details for Web of Science ID 000313145300020

    View details for PubMedID 23223106

  • Measuring the labor pain experience: delivery still far off INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Cohen, S. E. 2013; 22 (1): 6-9

    View details for DOI 10.1016/j.ijoa.2012.10.002

    View details for Web of Science ID 000315829600002

    View details for PubMedID 23182607

  • Peripartum outcomes and anaesthetic management of parturients with moderate to complex congenital heart disease or pulmonary hypertension ANAESTHESIA Maxwell, B. G., El-Sayed, Y. Y., Riley, E. T., Carvalho, B. 2013; 68 (1): 52-59

    Abstract

    We performed a retrospective cohort analysis of pregnancies among women with moderate to complex congenital heart disease or pulmonary hypertension over a 12-year period, resulting in a cohort of 107 cases in 65 women. Neuraxial analgesia or anaesthesia was provided in 84%, 89% and 95% of spontaneous vaginal, operative vaginal and caesarean deliveries, respectively. The caesarean delivery rate was 43% compared to our institution average of 27% over the same period (p = 0.02), and 38% had operative vaginal deliveries compared to a 10.5% institution rate (p < 0.01). Invasive monitoring was used in 28% of all deliveries. There were one maternal and two neonatal deaths. This study provides detailed anaesthetic and peripartum management of women with congenital heart disease, a patient population in whom evidence-based practice and data are largely lacking. We observed a predominance of neuraxial anaesthetic techniques, increased caesarean and operative delivery rates, and favourable maternal and neonatal outcomes. Multicentre studies and registries to compare anaesthetic and obstetric management strategies further and delineate risk factors for adverse outcomes are required.

    View details for DOI 10.1111/anae.12058

    View details for Web of Science ID 000312304000012

    View details for PubMedID 23121251

  • Intrathecal morphine 100 and 200 mu g for post-cesarean delivery analgesia: a trade-off between analgesic efficacy and side effects INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Wong, J. Y., Carvalho, B., Riley, E. T. 2013; 22 (1): 36-41

    Abstract

    Intrathecal morphine is highly effective for post-cesarean analgesia; however, the optimal dose is yet to be established. The aim of this study was to compare analgesia and side effects after a change in institutional practice to give 200 μg rather than 100 μg.We conducted a retrospective chart review of 241 patients who had an elective cesarean delivery and received either 100 or 200 μg of intrathecal morphine. The primary outcome variables were mean and peak verbal pain scores (0-10) and analgesic use (milligram-morphine equivalents). Postoperative administration of antiemetics, antipruritics and episodes of nausea or vomiting were recorded. Data are reported as mean±SD or percentages with P<0.05 considered statistically significant.Women receiving intrathecal morphine 200 μg had lower pain scores and opioid use compared with morphine 100 μg. Mean verbal pain scores were 1.6±1.1 versus 2.0±1.1 (P=0.01) and peak verbal pain scores were 4.9±2.0 versus 5.6±1.8, respectively (P=0.008). The group receiving 200 μg used less opioids in the first 24 h after surgery (44±35 versus 54±35 milligram-morphine equivalents, respectively, P=0.04) and received less intravenous opioids (18% versus 30%, P=0.02). However, women receiving intrathecal morphine 200 μg had more nausea (mean number of episodes of nausea 1.9±1.3 versus 1.6±1.3, P=0.037) and used more antiemetics (52% versus 24%, P<0.0001).Intrathecal morphine 200 μg provided better analgesia but with more nausea compared with morphine 100 μg. Our results can be used to help guide intrathecal morphine dosing in cesarean delivery based on patient preference for analgesia versus side effects.

    View details for DOI 10.1016/j.ijoa.2012.09.006

    View details for Web of Science ID 000315829600007

    View details for PubMedID 23159009

  • Failed epidural top-up for cesarean delivery for failure to progress in labor: the case against single-shot spinal anesthesia INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B. 2012; 21 (4): 357-359

    View details for DOI 10.1016/j.ijoa.2011.06.012

    View details for Web of Science ID 000310409000010

    View details for PubMedID 22112917

  • Collecting And Measuring Wound Exudate Biochemical Mediators In Surgical Wounds JOVE-JOURNAL OF VISUALIZED EXPERIMENTS Carvalho, B., Clark, D. J., Yeomans, D., Angst, M. S. 2012

    Abstract

    We describe a methodology by which we are able to collect and measure biochemical inflammatory and nociceptive mediators at the surgical wound site. Collecting site-specific biochemical markers is important to understand the relationship between levels in serum and surgical wound, determine any associations between mediator release, pain, analgesic use and other outcomes of interest, and evaluate the effect of systemic and peripheral drug administration on surgical wound biochemistry. This methodology has been applied to healthy women undergoing elective cesarean delivery with spinal anesthesia. We have measured wound exudate and serum mediators at the same time intervals as patient's pain scores and analgesics consumption for up to 48 hours post-cesarean delivery. Using this methodology we have been able to detect various biochemical mediators including nerve growth factor (NGF), prostaglandin E2 (PG-E2) substance P, IL-1β, IL-2, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, TNFα, INFγ, G-CSF, GM-CSF, MCP-1 and MIP-1β. Studies applying this human surgical wound bioassay have found no correlations between wound and serum cytokine concentrations or their time-release profile (J Pain. 2008; 9(7):650-7).(1) We also documented the utility of the technique to identify drug-mediated changes in wound cytokine content.

    View details for DOI 10.3791/50133

    View details for Web of Science ID 000209225700056

  • Does intrathecal analgesia reduce the subsequent minimum local analgesic concentration of epidural bupivacaine? ANAESTHESIA Carvalho, B., Landau, R. 2012; 67 (9): 1054-1055
  • Continuous spinal anesthesia for Cesarean hysterectomy and massive hemorrhage in a parturient with placenta increta CANADIAN JOURNAL OF ANESTHESIA-JOURNAL CANADIEN D ANESTHESIE Sultan, P., Hilton, G., Butwick, A., Carvalho, B. 2012; 59 (5): 473-477

    Abstract

    We present anesthetic management using a continuous spinal anesthesia (CSA) technique in a patient with placenta increta who underwent elective Cesarean hysterectomy with massive postpartum hemorrhage.A 34-yr-old parturient (G3P2) was scheduled for Cesarean delivery and possible hysterectomy at 35(+3) weeks due to suspected placenta accreta. Her body mass index was 21 kg·m(-2) and she had a reassuring airway. Inadvertent dural puncture occurred during combined spinal-epidural (CSE) placement, and a decision was made to thread the epidural catheter and utilize a CSA technique. Following delivery of a healthy infant, morbid adherence of the placenta to the myometrium was confirmed, and a supracervical hysterectomy was performed. Eight litres of blood loss occurred postpartum requiring resuscitation with crystalloid 3,800 mL, colloid 1,500 mL, red blood cells 16 units, fresh frozen plasma 16 units, platelets 4 units, and cryoprecipitate 1 unit. The patient developed pulmonary edema requiring conversion to general anesthesia. The patient's cardiovascular status was stable throughout surgery, and her lungs were mechanically ventilated for 18 hr postoperatively in the intensive care unit. The intrathecal catheter was removed 24 hr after placement. She developed no adverse neurological sequelae and reported no postdural puncture headache. The pathology report confirmed placenta increta.A CSA technique may be a viable option in the event of inadvertent dural puncture during planned CSE or epidural placement in patients with a reassuring airway undergoing Cesarean delivery. Although a catheter-based neuraxial technique is appropriate for Cesarean hysterectomy for abnormal placentation, conversion to general anesthesia may be required in the event of massive perioperative hemorrhage and fluid resuscitation.

    View details for DOI 10.1007/s12630-012-9681-0

    View details for PubMedID 22395824

  • The quality of CPR deteriorates during transport in simulated maternal arrests 15th World-Federation-of-Societies-of-Anaesthesiologists (WFSA) World Congress of Anaesthesiologists Wong, J., Lipman, S., Cohen, S., Arafeh, J., Carvalho, B. OXFORD UNIV PRESS. 2012: 201–202
  • Spinal anaesthesia for caesarean delivery in a parturient with babesiosis and Lyme disease ANAESTHESIA Sultan, P., Green, C., Riley, E., Carvalho, B. 2012; 67 (2): 180-183

    Abstract

    We present a case of a parturient with babesiosis and Lyme disease who was scheduled for elective caesarean section. The caesarean section was performed under spinal anaesthesia, and the patient had a coronary artery dissection 4 days postoperatively. Neuraxial anaesthesia and possible mechanisms for the coronary artery dissection in a patient with babesiosis and Lyme disease are discussed.

    View details for DOI 10.1111/j.1365-2044.2011.06941.x

    View details for Web of Science ID 000299158200012

    View details for PubMedID 22251109

  • Non-invasive haemoglobin measurement in patients undergoing elective Caesarean section BRITISH JOURNAL OF ANAESTHESIA Butwick, A., Hilton, G., Carvalho, B. 2012; 108 (2): 271-277

    Abstract

    The ability to measure haemoglobin (Hb) real-time and non-invasively offers important clinical value in the assessment of acute changes in maternal Hb during the peripartum period. This study evaluates the Masimo Rainbow SET(®) Radical-7 Pulse CO-Oximeter in a pregnant population undergoing Caesarean section (CS).Fifty patients undergoing elective CS were enrolled in this prospective, controlled study and followed for 48 h after surgery. Non-invasive Masimo Hb (SpHb) values were compared with laboratory Hb values from venous blood samples drawn at baseline, immediately post-CS, and 24 h post-CS using the Bland-Altman plots. Longitudinal analysis of SpHb changes over time was performed using mixed-effects regression modelling.For the comparison between SpHb and laboratory Hb, SpHb displayed a significant positive bias at baseline {1.22 g dl(-1) [95% confidence interval (CI): 0.89-1.54]} and at 24 h post-CS [1.36 g dl(-1) (95% CI: 1.04-1.68)]. The bias immediately post-CS was 0.14 g dl(-1) (95% CI: -0.18 to 0.46). The limits of agreement at baseline, immediately post-CS, and at 24 h post-CS were: -0.9 and 3.33, -2.35 and 2.56, and -0.55 and 3.27 g dl(-1), respectively. The mean decrease in SpHb from baseline to 48 h post-CS was ∼1 g dl(-1).The variability in bias and limits of agreements of the Rainbow SET(®) Radical-7 Pulse CO-Oximeter SpHb may limit its clinical utility for assessing Hb concentration in patients undergoing elective CS. Modifications are needed in the calibration of the device to improve accuracy and precision in an obstetric setting. The study was registered at clinicaltrials.gov (NCT01108471) before participant enrolment: URL=http://clinicaltrials.gov/ct2/show/NCT01108471?term=butwick&rank=1.

    View details for DOI 10.1093/bja/aer373

    View details for Web of Science ID 000299414800015

    View details for PubMedID 22116296

  • Ultrasound-guided popliteal nerve block in a patient with malignant degeneration of neurofibromatosis 1. Case reports in anesthesiology Desai, A., Carvalho, B., Hansen, J., Hill, J. 2012; 2012: 753769-?

    Abstract

    A 41-year-old female patient with neurofibromatosis 1 presented with new neurologic deficits secondary to malignant degeneration of a tibial lesion. Ultrasound mapping of the popliteal nerve revealed changes consistent with an intraneural neurofibroma. Successful popliteal nerve blockade was achieved under ultrasound guidance.

    View details for DOI 10.1155/2012/753769

    View details for PubMedID 22649742

    View details for PubMedCentralID PMC3357589

  • Collecting and measuring wound exudate biochemical mediators in surgical wounds. Journal of visualized experiments : JoVE Carvalho, B., Clark, D. J., Yeomans, D., Angst, M. S. 2012

    Abstract

    We describe a methodology by which we are able to collect and measure biochemical inflammatory and nociceptive mediators at the surgical wound site. Collecting site-specific biochemical markers is important to understand the relationship between levels in serum and surgical wound, determine any associations between mediator release, pain, analgesic use and other outcomes of interest, and evaluate the effect of systemic and peripheral drug administration on surgical wound biochemistry. This methodology has been applied to healthy women undergoing elective cesarean delivery with spinal anesthesia. We have measured wound exudate and serum mediators at the same time intervals as patient's pain scores and analgesics consumption for up to 48 hours post-cesarean delivery. Using this methodology we have been able to detect various biochemical mediators including nerve growth factor (NGF), prostaglandin E2 (PG-E2) substance P, IL-1β, IL-2, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, TNFα, INFγ, G-CSF, GM-CSF, MCP-1 and MIP-1β. Studies applying this human surgical wound bioassay have found no correlations between wound and serum cytokine concentrations or their time-release profile (J Pain. 2008; 9(7):650-7).(1) We also documented the utility of the technique to identify drug-mediated changes in wound cytokine content.

    View details for DOI 10.3791/50133

    View details for PubMedID 23117346

  • Intrathecal fentanyl added to bupivacaine and morphine for cesarean delivery may induce a subtle acute opioid tolerance INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Drover, D. R., Ginosar, Y., Cohen, S. E., Riley, E. T. 2012; 21 (1): 29-34

    Abstract

    Previous studies have demonstrated that the addition of intrathecal fentanyl to a spinal anesthetic for cesarean delivery improves intraoperative analgesia. However, intrathecal fentanyl may induce acute tolerance to opioids. The objective of this study was to investigate whether the addition of intrathecal fentanyl to spinal anesthesia with intrathecal morphine increases postoperative analgesic requirements and pain scores.In this randomized, double-blinded study, 40 women having elective cesarean delivery were enrolled. Patients received spinal anesthesia with hyperbaric bupivacaine 12 mg, morphine 200 μg, and fentanyl 0, 5, 10 or 25 μg. Each patient received intravenous patient-controlled analgesia morphine for 24h postoperatively. Outcome measures included postoperative morphine usage and pain scores, as well as intraoperative pain, nausea, hypotension and vasopressor use.Total morphine use over the 24-h post-spinal study period was similar among the study groups (P=0.129). Postoperative pain scores were higher in patients receiving fentanyl 5, 10 and 25 μg compared to fentanyl 0 μg control group (P=0.003).The study results suggest that intrathecal fentanyl may induce acute tolerance to intrathecal morphine. However, because there was no difference in postoperative analgesia requirement and the difference in pain scores was small, the clinical significance of this finding is uncertain.

    View details for DOI 10.1016/j.ijoa.2011.09.002

    View details for Web of Science ID 000301325800006

    View details for PubMedID 22100823

  • Labor Room Setting Compared With the Operating Room for Simulated Perimortem Cesarean Delivery A Randomized Controlled Trial OBSTETRICS AND GYNECOLOGY Lipman, S., Daniels, K., Cohen, S. E., Carvalho, B. 2011; 118 (5): 1090-1094

    Abstract

    To compare the labor room and operating room for perimortem cesarean delivery during simulated maternal arrests occurring outside the operating room. We hypothesized transport to the operating room for perimortem cesarean delivery would delay incision and other important resuscitation milestones.We randomized 15 teams composed of obstetricians, nurses, anesthesiologists, and neonatal staff to perform perimortem cesarean delivery in the labor room or operating room. A manikin with an abdominal model overlay was used for simulated cesarean delivery. The scenario began in the labor room with maternal cardiopulmonary arrest and fetal bradycardia. The primary outcome was time to incision. Secondary outcomes included times to important milestones, percentage of tasks completed, and type of incision.The median (interquartile range) times from time zero to incision were 4:25 (3:59-4:50) and 7:53 (7:18-8:57) minutes in the labor room and operating room groups, respectively (P=.004). Fifty-seven percent of labor room teams and 14% of operating room teams achieved delivery within 5 minutes. Contacting the neonatal team, placing the defibrillator, resuming compressions after analysis, and endotracheal intubation all occurred more rapidly in the labor room group.Perimortem cesarean delivery performed in the labor room was significantly faster than perimortem cesarean delivery performed after moving to the operating room. Delivery within 5 minutes was challenging in either location despite optimal study conditions (eg, the manikin was light and easily moved; teams knew the scenario mandated perimortem cesarean delivery and were aware of being timed). Our findings imply that perimortem cesarean delivery during actual arrest would require more than 5 minutes and should be performed in the labor room rather than relocating to the operating room.

    View details for DOI 10.1097/AOG.0b013e3182319a08

    View details for Web of Science ID 000296292600017

    View details for PubMedID 22015877

  • Epidural Catheter Removal in Patients on Warfarin Thromboprophylaxis A More Cautious Interpretation of Results Required? REGIONAL ANESTHESIA AND PAIN MEDICINE Carvalho, B., Mariano, E. R., Butwick, A. J. 2011; 36 (6): 632-632

    View details for DOI 10.1097/AAP.0b013e31822e0c7e

    View details for Web of Science ID 000296532100021

    View details for PubMedID 22024706

  • Endotracheal tube cuff pressure monitoring: a review of the evidence. Journal of perioperative practice Sultan, P., Carvalho, B., Rose, B. O., Cregg, R. 2011; 21 (11): 379-386

    Abstract

    Tracheal intubation constitutes a routine part of anaesthetic practice both in the operating theatre as well as in the care of critically ill patients. The procedure is estimated to be performed 13-20 million times annually in the United States alone. There has been a recent renewal of interest in the morbidity associated with endotracheal tube cuff overinflation, particularly regarding the rationale and requirement for endotracheal tube cuff monitoring intra-operatively.

    View details for PubMedID 22165491

  • Neuraxial blockade for external cephalic version: a systematic review INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Sultan, P., Carvalho, B. 2011; 20 (4): 299-306

    Abstract

    The desire to decrease the number of cesarean deliveries has renewed interest in external cephalic version. The rationale for using neuraxial blockade to facilitate external cephalic version is to provide abdominal muscular relaxation and reduce patient discomfort during the procedure, so permitting successful repositioning of the fetus to a cephalic presentation. This review systematically examined the current evidence to determine the safety and efficacy of neuraxial anesthesia or analgesia when used for external cephalic version.A systematic literature review of studies that examined success rates of external cephalic version with neuraxial anesthesia was performed. Published articles written in English between 1945 and 2010 were identified using the Medline, Cochrane, EMBASE and Web of Sciences databases.Six, randomized controlled studies were identified. Neuraxial blockade significantly improved the success rate in four of these six studies. A further six non-randomized studies were identified, of which four studies with control groups found that neuraxial blockade increased the success rate of external cephalic version. Despite over 850 patients being included in the 12 studies reviewed, placental abruption was reported in only one patient with a neuraxial block, compared with two in the control groups. The incidence of non-reassuring fetal heart rate requiring cesarean delivery in the anesthesia groups was 0.44% (95% CI 0.15-1.32).Neuraxial blockade improved the likelihood of success during external cephalic version, although the dosing regimen that provides optimal conditions for successful version is unclear. Anesthetic rather than analgesic doses of local anesthetics may improve success. The findings suggest that neuraxial blockade does not compromise maternal or fetal safety during external cephalic version.

    View details for DOI 10.1016/j.ijoa.2011.07.001

    View details for Web of Science ID 000297087100006

    View details for PubMedID 21925869

  • Prior epidural lidocaine alters the pharmacokinetics and drug effects of extended-release epidural morphine (DepoDur®) after cesarean delivery. Anesthesia and analgesia Atkinson Ralls, L., Drover, D. R., Clavijo, C. F., Carvalho, B. 2011; 113 (2): 251-258

    Abstract

    A potential physicochemical interaction between epidural local anesthetics and extended-release epidural morphine (EREM) could negate the sustained release. In this study, we sought to determine the pharmacokinetic and drug effects of prior epidural lidocaine administration on EREM.Thirty healthy women undergoing cesarean delivery were enrolled in this randomized study. Patients received 8 mg EREM 1 hour after either a combined spinal-epidural (intrathecal bupivacaine and fentanyl 20 μg with no epidural medication; group SE) or an epidural anesthetic (epidural 2% lidocaine with fentanyl 100 μg; group E). Maximal concentration (Cmax), time to Cmax (Tmax), and AUC(0-last) (area under the concentration-time curve until the last plasma concentration that was below the limit of quantitation) for morphine levels were determined from a plasma sample at 0, 5, 10, 15, and 30 minutes, and 1, 4, 8, 12, 24, 36, 48, and 72 hours. Drug effects including pain, analgesic use, and side effects were measured for 72 hours after cesarean delivery.Epidural lidocaine administration (20-35 mL) 1 hour before epidural EREM administration increased the Cmax in group E (11.1 ± 4.9) compared with group SE (8.3 ± 7.1 ng/mL) (P = 0.038). There were no significant effects on Tmax and AUC(0-last) of venous morphine between the groups (P > 0.05). There was an increased incidence in vomiting, oxygen use, and hypotension in group E (patients who received lidocaine before EREM).A large dose of epidural lidocaine 1 hour before EREM administration alters the pharmacokinetics and drug effects of EREM. Clinicians must apply caution when EREM is administered even 1 hour after an epidural lidocaine "top-up" for cesarean delivery.

    View details for DOI 10.1213/ANE.0b013e318222f59c

    View details for PubMedID 21642610

  • Prior Epidural Lidocaine Alters the Pharmacokinetics and Drug Effects of Extended-Release Epidural Morphine (DepoDur (R)) After Cesarean Delivery ANESTHESIA AND ANALGESIA Ralls, L. A., Drover, D. R., Clavijo, C. F., Carvalho, B. 2011; 113 (2): 251-258

    Abstract

    A potential physicochemical interaction between epidural local anesthetics and extended-release epidural morphine (EREM) could negate the sustained release. In this study, we sought to determine the pharmacokinetic and drug effects of prior epidural lidocaine administration on EREM.Thirty healthy women undergoing cesarean delivery were enrolled in this randomized study. Patients received 8 mg EREM 1 hour after either a combined spinal-epidural (intrathecal bupivacaine and fentanyl 20 μg with no epidural medication; group SE) or an epidural anesthetic (epidural 2% lidocaine with fentanyl 100 μg; group E). Maximal concentration (Cmax), time to Cmax (Tmax), and AUC(0-last) (area under the concentration-time curve until the last plasma concentration that was below the limit of quantitation) for morphine levels were determined from a plasma sample at 0, 5, 10, 15, and 30 minutes, and 1, 4, 8, 12, 24, 36, 48, and 72 hours. Drug effects including pain, analgesic use, and side effects were measured for 72 hours after cesarean delivery.Epidural lidocaine administration (20-35 mL) 1 hour before epidural EREM administration increased the Cmax in group E (11.1 ± 4.9) compared with group SE (8.3 ± 7.1 ng/mL) (P = 0.038). There were no significant effects on Tmax and AUC(0-last) of venous morphine between the groups (P > 0.05). There was an increased incidence in vomiting, oxygen use, and hypotension in group E (patients who received lidocaine before EREM).A large dose of epidural lidocaine 1 hour before EREM administration alters the pharmacokinetics and drug effects of EREM. Clinicians must apply caution when EREM is administered even 1 hour after an epidural lidocaine "top-up" for cesarean delivery.

    View details for DOI 10.1213/ANE.0b013e318222f59c

    View details for Web of Science ID 000293064500009

  • Challenges in Interpreting Joined Allelic Combinations of OPRM1 and COMT Genes ANESTHESIA AND ANALGESIA Landau, R., Ortner, C., Carvalho, B. 2011; 113 (2): 432-432

    View details for DOI 10.1213/ANE.0b013e31821f154f

    View details for Web of Science ID 000293064500047

    View details for PubMedID 21788333

  • The Proseal laryngeal mask airway and elective caesarean section ANAESTHESIA AND INTENSIVE CARE Dyer, R. A., James, M. F., Butwick, A. J., Carvalho, B. 2011; 39 (4): 760-761

    View details for Web of Science ID 000293264000036

    View details for PubMedID 21823396

  • Non-invasive measurement of hemoglobin during cesarean hysterectomy: a case series INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Butwick, A. J., Hilton, G., Riley, E. T., Carvalho, B. 2011; 20 (3): 240-245

    Abstract

    Obstetric patients diagnosed with abnormal placentation (placenta accreta, increta or percreta) are at increased risk of major postpartum hemorrhage and cesarean hysterectomy. Obstetric anesthesiologists are primarily involved in intraoperative transfusion management in these cases. Hemoglobin assessment is invaluable for assisting transfusion decision-making during the acute period of obstetric hemorrhage. However, laboratory and point-of-care tests of hemoglobin concentration are time-dependent and intermittent, and do not provide a real-time assessment of change during the acute phase of blood loss. A new non-invasive hemoglobin monitor has been introduced recently, which provides real-time measurement of hemoglobin values (SpHb) using multi-wavelength pulse co-oximetry. We present a review of five patients with suspected abnormal placentation who received SpHb monitoring during cesarean hysterectomy at our institution. We discuss the potential clinical utility of non-invasive hemoglobin monitoring for pregnant patients at high risk of obstetric hemorrhage, and the potential role of SpHb in guiding transfusion therapy.

    View details for DOI 10.1016/j.ijoa.2011.03.009

    View details for Web of Science ID 000293042800009

    View details for PubMedID 21640577

  • Oxytocin for labour and caesarean delivery: implications for the anaesthesiologist CURRENT OPINION IN ANESTHESIOLOGY Dyer, R. A., Butwick, A. J., Carvalho, B. 2011; 24 (3): 255-261

    Abstract

    The implications of the obstetric use of oxytocin for obstetric anaesthesia practice are summarised. The review focuses on recent research on the uterotonic effects of oxytocin for prophylaxis and management of uterine atony during caesarean delivery.Oxytocin remains the first-line agent in the prevention and management of uterine atony. In-vitro and in-vivo studies show that prior exposure to oxytocin induces uterine muscle oxytocin receptor desensitization. This may influence oxytocin dosing for adequate uterine tone following delivery. Oxytocin has important cardiovascular side-effects (hypotension, tachycardia and myocardial ischaemia). Recent studies suggest that the effective dose of oxytocin for prophylaxis against uterine atony during caesarean delivery is significantly lower than the 5-10 IU historically used by anaesthesiologists. Slow administration of small bolus doses of oxytocin minimises maternal haemodynamic disturbance. Continuous oxytocin infusions are recommended for maintaining uterine tone after bolus administration, although ideal infusion rates are still to be established. The efficacy of the long-acting oxytocin analogue carbetocin requires further investigation. Recommendations are presented for oxytocin dosing during caesarean delivery.Oxytocin remains the first-line uterotonic after vaginal and caesarean delivery. Recent research elucidates the therapeutic range of oxytocin during caesarean delivery, as well as receptor desensitization. Evidenced-based protocols for the prevention and treatment of uterine atony during caesarean delivery are recommended.

    View details for DOI 10.1097/ACO.0b013e328345331c

    View details for Web of Science ID 000289974800004

    View details for PubMedID 21415725

  • A sensitive assay for the quantification of morphine and its active metabolites in human plasma and dried blood spots using high-performance liquid chromatography-tandem mass spectrometry ANALYTICAL AND BIOANALYTICAL CHEMISTRY Clavijo, C. F., Hoffman, K. L., Thomas, J. J., Carvalho, B., Chu, L. F., Drover, D. R., Hammer, G. B., Christians, U., Galinkin, J. L. 2011; 400 (3): 715-728

    Abstract

    Opioids such as morphine are the cornerstone of pain treatment. The challenge of measuring the concentrations of morphine and its active metabolites in order to assess human pharmacokinetics and monitor therapeutic drugs in children requires assays with high sensitivity in small blood volumes. We developed and validated a semi-automated LC-MS/MS assay for the simultaneous quantification of morphine and its active metabolites morphine 3β-glucuronide (M3G) and morphine 6β-glucuronide (M6G) in human plasma and in dried blood spots (DBS). Reconstitution in water (DBS only) and addition of a protein precipitation solution containing the internal standards were the only manual steps. Morphine and its metabolites were separated on a Kinetex 2.6-μm PFP analytical column using an acetonitrile/0.1% formic acid gradient. The analytes were detected in the positive multiple reaction mode. In plasma, the assay had the following performance characteristics: range of reliable response of 0.25-1000 ng/mL (r(2) > 0.99) for morphine, 1-1,000 ng/mL (r(2) > 0.99) for M3G, and 2.5-1,000 ng/mL for M6G. In DBS, the assay had a range of reliable response of 1-1,000 ng/mL (r(2) > 0.99) for morphine and M3G, and of 2.5-1,000 ng/mL for M6G. For inter-day accuracy and precision for morphine, M3G and M6G were within 15% of the nominal values in both plasma and DBS. There was no carryover, ion suppression, or matrix interferences. The assay fulfilled all predefined acceptance criteria, and its sensitivity using DBS samples was adequate for the measurement of pediatric pharmacokinetic samples using a small blood of only 20-50 μL.

    View details for DOI 10.1007/s00216-011-4775-z

    View details for Web of Science ID 000289297000015

    View details for PubMedID 21400080

  • Crossing the pond: applying to train in the USA. British journal of hospital medicine Qadan, M., Kastenberg, Z., Carvalho, B., Sultan, P. 2011; 72 (4): M50-2

    View details for PubMedID 21537230

  • ED50 and ED95 of Intrathecal Bupivacaine in Morbidly Obese Patients Undergoing Cesarean Delivery ANESTHESIOLOGY Carvalho, B., Collins, J., Drover, D. R., Ralls, L. A., Riley, E. T. 2011; 114 (3): 529-535

    Abstract

    It has been suggested that morbidly obese parturients may require less local anesthetic for spinal anesthesia. The aim of this study was to determine the effective dose (ED(50)/ED(95)) of intrathecal bupivacaine for cesarean delivery in morbidly obese patients.Morbidly obese parturients (body mass index equal to or more than 40) undergoing elective cesarean delivery were enrolled in this double-blinded study. Forty-two patients were randomly assigned to receive intrathecal hyperbaric bupivacaine in doses of 5, 6, 7, 8, 9, 10, or 11 mg (n = 6 per group) coadministered with 200 μg morphine and 10 μg fentanyl. Success (induction) was defined as block height to pinprick equal to or more than T6 and success (operation) as success (induction) plus no requirement for epidural supplementation throughout surgery. The ED(50)/ED(95) values were determined using a logistic regression model.ED(50) and ED(95) (with 95% confidence intervals) for success (operation) were 9.8 (8.6-11.0) and 15.0 (10.0-20.0), respectively, and were similar to corresponding values of a nonobese population determined previously using similar methodology. We were unable to measure ED(50)/ED(95) values for success (induction) because so few blocks failed initially, even at the low-dose range. There were no differences with regard to secondary outcomes (i.e., hypotension, vasopressor use, nausea, and vomiting).Obese and nonobese patients undergoing cesarean delivery do not appear to respond differently to modest doses of intrathecal bupivacaine. This dose-response study suggests that doses of intrathecal bupivacaine less than 10 mg may not adequately ensure successful intraoperative anesthesia. Even when the initial block obtained with a low dose is satisfactory, it will not guarantee adequate anesthesia throughout surgery.

    View details for DOI 10.1097/ALN.0b013e318209a92d

    View details for PubMedID 21307769

  • Anticoagulant and antithrombotic drugs in pregnancy: what are the anesthetic implications for labor and cesarean delivery? JOURNAL OF PERINATOLOGY Butwick, A. J., Carvalho, B. 2011; 31 (2): 73-84

    Abstract

    Neuraxial anesthetic techniques are commonly used during the peripartum period to provide effective pain relief for labor and anesthesia during cesarean delivery. Major neurologic complications are rare after neuraxial anesthesia; however, spinal hematoma is associated with catastrophic neurologic outcomes (including lower-limb paralysis). Anticoagulant and antithrombotic drugs can increase the risk of spinal hematoma after neuraxial anesthesia, and better understanding of the pharmacokinetics and pharmacodynamics of anticoagulants has led to greater appreciation for withholding anticoagulation before and after neuraxial anesthesia. A number of national anesthetic societies have produced guidelines for performing neuraxial anesthesia in patients receiving anticoagulation. However, there is limited information about anesthetic implications of anticoagulation during the peripartum period. This article will review the risks of spinal hematoma after neuraxial anesthesia in pregnant patients; current guidelines for neuraxial anesthesia for anticoagulated patients; and relevant pharmacological data of specific anticoagulant and antithrombotic drugs in pregnancy.

    View details for DOI 10.1038/jp.2010.64

    View details for Web of Science ID 000286808100001

    View details for PubMedID 20559281

  • Neuraxial Morphine and Respiratory Depression Finding the Right Balance DRUGS Sultan, P., Gutierrez, M. C., Carvalho, B. 2011; 71 (14): 1807-1819

    Abstract

    Morphine is a drug commonly administered via the epidural or intrathecal route, and is regarded by many as the 'gold-standard' single-dose neuraxial opioid due to its postoperative analgesic efficacy and prolonged duration of action. However, respiratory depression is a recognized side effect of neuraxial morphine administered in the perioperative setting. We conducted an extensive review of articles published since 1945 that examine respiratory depression or failure associated with perioperative intrathecal or epidural morphine use. Respiratory depression was previously thought to result from the interaction of opioid in the cerebrospinal fluid with ventral medullary opioid receptors. More recently, the preBötzinger complex located in the medulla has been identified as the site responsible for the decrease in respiratory rate following systemic administration of opioids. Neurons in the preBötzinger complex expressing neurokinin-1 receptors are selectively inhibited by opioids, and therefore are the mediators of opioid-induced respiratory depression. Epidural, intrathecal and plasma pharmacokinetics of opioids are complex, vary between neuraxial compartments, and can even differ within the epidural space itself depending upon level of insertion. Caution should be exercised when prescribing systemic opioids (intravenous or oral) in addition to neuraxial morphine as this can compound the potential for early or delayed respiratory depression. There is a wide range of incidences for respiratory depression following neuraxial morphine in a perioperative setting. Disparity of definitions used for the diagnosis of respiratory depression in the literature precludes identification of the exact incidence of this rare event. The optimal neuraxial opioid dose is a balance between the conflicting demands of providing optimal analgesia while minimizing dose-related adverse effects. Dose-response studies show that neuraxial morphine appears to have an analgesic efficacy 'ceiling'. The optimal 'single-shot' intrathecal dose appears to be 0.075-0.15 mg and the ideal 'single-shot' epidural morphine dose is 2.5-3.75 mg. Analgesic efficacy studies have not been adequately powered to show differences in the incidence of clinically significant respiratory depression. Opioid antagonists such as naloxone to prevent or treat opioid-induced respiratory depression have a number of limitations. Researchers have recently focused on non-opioid drugs such as serotonin receptor agonists. Early evidence suggests that ampakine (α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid [AMPA]) receptor modulators may be effective at reducing opioid-induced respiratory depression while maintaining analgesia. Sodium/proton exchanger type 3 (NHE3) inhibitors, which act centrally on respiratory pathways, also warrant further study.

    View details for PubMedID 21942973

  • The Role of Interleukin-1 in Wound Biology. Part I: Murine In Silico and In Vitro Experimental Analysis ANESTHESIA AND ANALGESIA Hu, Y., Liang, D., Li, X., Liu, H., Zhang, X., Zheng, M., Dill, D., Shi, X., Qiao, Y., Yeomans, D., Carvalho, B., Angst, M. S., Clark, J. D., Peltz, G. 2010; 111 (6): 1525-1533

    Abstract

    Wound healing is a multistep, complex process that involves the coordinated action of multiple cell types. Conflicting results have been obtained when conventional methods have been used to study wound biology. Therefore, we analyzed the wound response in a mouse genetic model.We analyzed inflammatory mediators produced within incisional wounds induced in 16 inbred mouse strains. Computational haplotype-based genetic analysis of inter-strain differences in the level of production of 2 chemokines in wounds was performed. An in vitro experimental analysis system was developed to investigate whether interleukin (IL)-1 could affect chemokine production by 2 different types of cells that are present within wounds.The level of 2 chemokines, keratinocyte-derived chemokine (KC) and macrophage inflammatory protein 1α, exhibited very large (75- and 463-fold, respectively) interstrain differences within wound tissue across this inbred strain panel. Genetic variation within Nalp1, an inflammasome component that regulates IL-1 production, correlated with the interstrain differences in KC and macrophage inhibitory protein 1α production. Consistent with the genetic correlation, IL-1β was shown to stimulate KC production by murine keratinocyte and fibroblast cell lines in vitro.Genetic variation within Nalp1 could contribute to interstrain differences in wound chemokine production by altering the amount of IL-1 produced.

    View details for DOI 10.1213/ANE.0b013e3181f5ef5a

    View details for PubMedID 20889942

  • Continuous Subcutaneous Instillation of Bupivacaine Compared to Saline Reduces Interleukin 10 and Increases Substance P in Surgical Wounds After Cesarean Delivery ANESTHESIA AND ANALGESIA Carvalho, B., Clark, D. J., Yeomans, D. C., Angst, M. S. 2010; 111 (6): 1452-1459

    Abstract

    Recent evidence suggests that locally delivered local anesthetics may exert tissue-damaging effects such as chondrolysis after intraarticular injection. Alteration of the inflammatory response is a potential mechanism for local anesthetic-induced tissue toxicity. In this study, we tested the effects of continuous local anesthetic infiltration on the release of inflammatory and nociceptive mediators in skin wounds after cesarean delivery.Thirty-eight healthy women undergoing cesarean delivery with spinal anesthesia were enrolled in this study, and were randomized to receive subcutaneous surgical wound infiltration with bupivacaine 5 mg/mL or saline at 2 mL/h for 24 hours after cesarean delivery. Wound exudate was sampled at 1, 3, 5, 7, and 24 hours after cesarean delivery using a subcutaneous wound drain technique. Cytokines, chemokines, substance P, prostaglandin E(2), and nerve growth factor were assayed using multiplex Bio-Plex® (Bio-Rad, Hercules, CA) and enzyme-linked immunosorbent assays.Bupivacaine wound infusion resulted in a significant decrease of interleukin 10 and increase of substance P in wounds compared with saline infusion (area under the 24-hour concentration-time curve; P < 0.001). No statistically significant differences were detected for other cytokines, nerve growth factor, and prostaglandin E(2).This study demonstrates that the continuous administration of clinically used doses of bupivacaine into wounds affects the local composition of wound mediators. Observed changes in interleukin 10 are compatible with a disruption of antiinflammatory mechanisms. Whether such modulation combined with the release of the proinflammatory mediator substance P results in an overall proinflammatory wound response will require future studies of wound healing.

    View details for DOI 10.1213/ANE.0b013e3181f579de

    View details for PubMedID 20861424

  • The Role of Interleukin-1 in Wound Biology. Part II: In Vivo and Human Translational Studies ANESTHESIA AND ANALGESIA Hu, Y., Liang, D., Li, X., Liu, H., Zhang, X., Zheng, M., Dill, D., Shi, X., Qiao, Y., Yeomans, D., Carvalho, B., Angst, M. S., Clark, J. D., Peltz, G. 2010; 111 (6): 1534-1542

    Abstract

    In the accompanying paper, we demonstrate that genetic variation within Nalp1 could contribute to interstrain differences in wound chemokine production through altering the amount of interleukin (IL)-1 produced. We further investigate the role of IL-1 in incisional wound biology and its effect on wound chemokine production in vivo and whether this mechanism could be active in human subjects.A well-characterized murine model of incisional wounding was used to assess the in vivo role of IL-1 in wound biology. The amount of 7 different cytokines/chemokines produced within an experimentally induced skin incision on a mouse paw and the nociceptive response was analyzed in mice treated with an IL-1 inhibitor. We also investigated whether human IL-1β or IL-1α stimulated the production of chemokines by primary human keratinocytes in vitro, and whether there was a correlation between IL-1β and chemokine levels in 2 experimental human wound paradigms.Administration of an IL-1 receptor antagonist to mice decreased the nociceptive response to an incisional wound, and reduced the production of multiple inflammatory mediators, including keratinocyte-derived chemokine (KC) and macrophage inhibitory protein (MIP)-1α, within the wounds. IL-1α and IL-1β stimulated IL-8 and GRO-α (human homologues of murine keratinocyte-derived chemokine) production by primary human keratinocytes in vitro. IL-1β levels were highly correlated with IL-8 in human surgical wounds, and at cutaneous sites of human ultraviolet B-induced sunburn injury.IL-1 plays a major role in regulating inflammatory mediator production in wounds through a novel mechanism; by stimulating the production of multiple cytokines and chemokines, it impacts clinically important aspects of wound biology. These data suggest that administration of an IL-1 receptor antagonist within the perioperative period could decrease postsurgical wound pain.

    View details for DOI 10.1213/ANE.0b013e3181f691eb

    View details for PubMedID 20889944

  • Effect of a Preemptive Femoral Nerve Block on Cytokine Release and Hyperalgesia in Experimentally Inflamed Skin of Human Volunteers REGIONAL ANESTHESIA AND PAIN MEDICINE Carvalho, B., Aleshi, P., Horstman, D. J., Angst, M. S. 2010; 35 (6): 514-519

    Abstract

    Tissue injury is associated with the local release of inflammatory and nociceptive mediators and the development of hyperalgesia. It is unclear whether interrupting neuronal signaling using regional anesthetic techniques at the time of the injury modifies local nociceptive and inflammatory processes. The aim of this study was to determine whether a peripheral nerve block at the time of tissue injury could modify the development of wound hyperalgesia and the local release of inflammatory and nociceptive mediators.Twelve healthy volunteers participated in this controlled, crossover, randomized study. A femoral nerve block or a sham block was established before inducing an experimental UVB burn on the thigh. Twenty-four hours later, the interstitial wound fluid was sampled, and mechanical and heat pain thresholds were assessed. Wound fluid concentrations of an array of cytokines, chemokines, nerve growth factor, prostaglandin E2, and substance P were determined.Skin inflammation was associated with the release of inflammatory and nociceptive mediators and resulted in significant tissue hyperalgesia (P < 0.001). However, the presence of a fully established peripheral nerve block at the time of tissue injury did not alter the development of hyperalgesia after regression of the block. Similarly, the presence of a peripheral nerve block did not modify the release of inflammatory or nociceptive mediators.These findings suggest that a preemptive, single-shot peripheral nerve block minimally affects wound hyperalgesia and inflammation. Continuous nerve block techniques may be better suited to alter nociceptive and inflammatory events in wounds beyond the duration of the block.

    View details for DOI 10.1097/AAP.0b013e3181faa107

    View details for PubMedID 20975465

  • Retrospective analysis of anesthetic interventions for obese patients undergoing elective cesarean delivery JOURNAL OF CLINICAL ANESTHESIA Butwick, A., Carvalho, B., Danial, C., Riley, E. 2010; 22 (7): 519-526

    Abstract

    To examine the relationship between body mass index (BMI), perioperative times, and anesthetic interventions in patients undergoing elective cesarean delivery.Retrospective chart review.University-affiliated hospital.All patients were ranked according to BMI (kg/m(2)) at the time of delivery. The BMI groups were designated a priori: ≤ 29.9 kg/m(2) (Group C); 30-34.9 kg/m(2) (Group I); 35-39.9 kg/m(2) (Group II), and ≥ 40 kg/m(2) (Group III). One hundred patients (25 pts per group) underwent elective cesarean delivery. Data collected included anesthetic technique, perioperative times, anesthesia-related costs, and neonatal outcomes.A higher percentage of Group III patients (60%) received combined spinal-epidural (CSE) anesthesia than did Group C or Group I (18% and 16%, respectively; P < 0.05). The total intraoperative period was significantly longer in Group III (101 min) compared with Groups C, I, and II (81 min, 90 min, and 92 min, respectively; P < 0.05). Total intraoperative time increased significantly with BMI (R = 0.394 kg/m(2); P < 0.001). The highest anesthesia-related costs during the study were generated by patients with BMI ≥ 40 kg/m(2).Our single-center experience showed that choice of anesthetic technique (CSE vs. spinal anesthesia) varies according to obesity class. Longer intraoperative periods must be considered in deciding upon the mode of anesthesia for patients with BMI ≥ 40 kg/m(2) who undergo elective cesarean delivery.

    View details for DOI 10.1016/j.jclinane.2010.01.005

    View details for Web of Science ID 000284791000006

    View details for PubMedID 21056808

  • A practical guide to undertaking out of programme experience in the United States of America. British journal of hospital medicine Sultan, P., Qadan, M., Pushpanathan, E., Carvalho, B. 2010; 71 (10): M158-9

    View details for PubMedID 20944517

  • Deficits in the provision of cardiopulmonary resuscitation during simulated obstetric crises AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY Lipman, S. S., Daniels, K. I., Carvalho, B., Arafeh, J., Harney, K., Puck, A., Cohen, S. E., Druzin, M. 2010; 203 (2)

    Abstract

    Previous work suggests the potential for suboptimal cardiopulmonary resuscitation (CPR) in the parturient but did not directly assess actual performance.We evaluated 18 videotaped simulations of maternal amniotic fluid embolus and resultant cardiac arrest. A checklist containing 10 current American Heart Association recommendations for advanced cardiac life support (ACLS) in obstetric patients was utilized. We evaluated which tasks were completed correctly and the time required to perform key actions.Proper compressions were delivered by our teams 56% of the time and ventilations 50% of the time. Critical interventions such as left uterine displacement and placing a firm back support prior to compressions were frequently neglected (in 44% and 22% of cases, respectively). The mean +/- SD overall composite score for the tasks was 45 +/- 12% (range, 20-60%). The neonatal team was called in a median (interquartile range) of 1:42 (0:44-2:18) minutes:seconds; 15 of 18 (83%) teams called only after the patient was completely unresponsive. Fifty percent of teams did not provide basic information to the neonatal teams as required by neonatal resuscitation provider guidelines.Multiple deficits were noted in the provision of CPR to parturients during simulated arrests, despite current ACLS certification for all participants. Current requirements for ACLS certification and training for obstetric staff may require revision.

    View details for DOI 10.1016/j.ajog.2010.02.022

    View details for Web of Science ID 000280234500037

    View details for PubMedID 20417476

  • Minimum effective bolus dose of oxytocin during elective Caesarean delivery BRITISH JOURNAL OF ANAESTHESIA Woo, C., McGlennan, A. 2010; 105 (1): 91-92

    View details for Web of Science ID 000278969500016

    View details for PubMedID 20560157

  • Minimum effective bolus dose of oxytocin during elective Caesarean delivery BRITISH JOURNAL OF ANAESTHESIA Breeze, E. 2010; 104 (6): 783-783

    View details for Web of Science ID 000277731100026

    View details for PubMedID 20460573

  • Neuraxial anesthesia in obstetric patients receiving anticoagulant and antithrombotic drugs INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Butwick, A. J., Carvalho, B. 2010; 19 (2): 193-201

    View details for DOI 10.1016/j.ijoa.2009.06.008

    View details for Web of Science ID 000277553700012

    View details for PubMedID 20202816

  • Minimum effective bolus dose of oxytocin during elective Caesarean delivery BRITISH JOURNAL OF ANAESTHESIA Butwick, A. J., Coleman, L., Cohen, S. E., Riley, E. T., Carvalho, B. 2010; 104 (3): 338-343

    Abstract

    The aim of this study was to determine the lowest effective bolus dose of oxytocin to produce adequate uterine tone (UT) during elective Caesarean delivery (CD).Seventy-five pregnant patients undergoing elective CD under spinal anaesthesia were randomized to receive oxytocin (0.5, 1, 3, 5 units) or placebo. UT was assessed by a blinded obstetrician as either adequate or inadequate, and using a verbal numerical scale score (0-10; 0, no UT; 10, optimal UT) at 2, 3, 6, and 9 min after oxytocin administration. Minimum effective doses of oxytocin were analysed (ED(50) and ED(95)) using logistic regression. Oxytocin-related side-effects (including hypotension) were recorded.There were no significant differences in the prevalence of adequate UT among the study groups at 2 min (73%, 100%, 93%, 100%, and 93% for 0, 0.5, 1, 3, and 5 units oxytocin, respectively). The high prevalence of adequate UT after placebo and low-dose oxytocin precluded determination of the ED(50) and ED(95). UT scores were significantly lower in patients receiving 0 unit oxytocin at 2 and 3 min compared with 3 and 5 units oxytocin (P<0.05, respectively). The prevalence of hypotension was significantly higher after 5 units oxytocin vs 0 unit at 1 min (47% vs 7%; P=0.04).The routine use of 5 units oxytocin during elective CD can no longer be recommended, as adequate UT can occur with lower doses of oxytocin (0.5-3 units).

    View details for DOI 10.1093/bja/aeq004

    View details for Web of Science ID 000274485900011

    View details for PubMedID 20150347

  • Cost-effectiveness of external cephalic version for term breech presentation BMC PREGNANCY AND CHILDBIRTH Tan, J. M., Macario, A., Carvalho, B., Druzin, M. L., El-Sayed, Y. Y. 2010; 10

    Abstract

    External cephalic version (ECV) is recommended by the American College of Obstetricians and Gynecologists to convert a breech fetus to vertex position and reduce the need for cesarean delivery. The goal of this study was to determine the incremental cost-effectiveness ratio, from society's perspective, of ECV compared to scheduled cesarean for term breech presentation.A computer-based decision model (TreeAge Pro 2008, Tree Age Software, Inc.) was developed for a hypothetical base case parturient presenting with a term singleton breech fetus with no contraindications for vaginal delivery. The model incorporated actual hospital costs (e.g., $8,023 for cesarean and $5,581 for vaginal delivery), utilities to quantify health-related quality of life, and probabilities based on analysis of published literature of successful ECV trial, spontaneous reversion, mode of delivery, and need for unanticipated emergency cesarean delivery. The primary endpoint was the incremental cost-effectiveness ratio in dollars per quality-adjusted year of life gained. A threshold of $50,000 per quality-adjusted life-years (QALY) was used to determine cost-effectiveness.The incremental cost-effectiveness of ECV, assuming a baseline 58% success rate, equaled $7,900/QALY. If the estimated probability of successful ECV is less than 32%, then ECV costs more to society and has poorer QALYs for the patient. However, as the probability of successful ECV was between 32% and 63%, ECV cost more than cesarean delivery but with greater associated QALY such that the cost-effectiveness ratio was less than $50,000/QALY. If the probability of successful ECV was greater than 63%, the computer modeling indicated that a trial of ECV is less costly and with better QALYs than a scheduled cesarean. The cost-effectiveness of a trial of ECV is most sensitive to its probability of success, and not to the probabilities of a cesarean after ECV, spontaneous reversion to breech, successful second ECV trial, or adverse outcome from emergency cesarean.From society's perspective, ECV trial is cost-effective when compared to a scheduled cesarean for breech presentation provided the probability of successful ECV is > 32%. Improved algorithms are needed to more precisely estimate the likelihood that a patient will have a successful ECV.

    View details for DOI 10.1186/1471-2393-10-3

    View details for Web of Science ID 000296428000001

    View details for PubMedID 20092630

    View details for PubMedCentralID PMC2826287

  • Survey of the Factors Associated with a Woman's Choice to Have an Epidural for Labor Analgesia. Anesthesiology research and practice Harkins, J., Carvalho, B., Evers, A., Mehta, S., Riley, E. T. 2010; 2010

    Abstract

    Objectives. The purpose of this study was to determine the factors associated with whether a woman received an epidural in labor and to determine the main source used to obtain information about labor epidurals. Methods. Over a one-month period, we surveyed all patients who labored, the day after their delivery. We used multiple logistic regression to identify potential predictive factors after initial univariate analysis. Results. 320 women who met enrollment criteria delivered during the study period and 94% completed the study. Of the 302 patients surveyed, 80% received an epidural for labor. Univariate analysis showed the following variables were associated with whether women received an epidural (P < .01): partner preference, prior epidural, language, education, type of insurance, age, duration, and pitocin use. Using computed multiple logistic regression only partner preference and prior epidural were associated with whether women received an epidural. Conclusion. It was not surprising that a previous epidural was predictive of a patient receiving an epidural. The strong association with partner preference and epidural use suggests this is an important factor when counseling pregnant women with regard to their decision to have a labor epidural.

    View details for DOI 10.1155/2010/356789

    View details for PubMedID 20721286

    View details for PubMedCentralID PMC2915618

  • An experimental paradigm for the prediction of Post-Operative Pain (PPOP). Journal of visualized experiments : JoVE Landau, R., Kraft, J. C., Flint, L. Y., Carvalho, B., Richebé, P., Cardoso, M., Lavand'homme, P., Granot, M., Yarnitsky, D., Cahana, A. 2010

    Abstract

    Many women undergo cesarean delivery without problems, however some experience significant pain after cesarean section. Pain is associated with negative short-term and long-term effects on the mother. Prior to women undergoing surgery, can we predict who is at risk for developing significant postoperative pain and potentially prevent or minimize its negative consequences? These are the fundamental questions that a team from the University of Washington, Stanford University, the Catholic University in Brussels, Belgium, Santa Joana Women's Hospital in São Paulo, Brazil, and Rambam Medical Center in Israel is currently evaluating in an international research collaboration. The ultimate goal of this project is to provide optimal pain relief during and after cesarean section by offering individualized anesthetic care to women who appear to be more 'susceptible' to pain after surgery. A significant number of women experience moderate or severe acute post-partum pain after vaginal and cesarean deliveries. (1) Furthermore, 10-15% of women suffer chronic persistent pain after cesarean section. (2) With constant increase in cesarean rates in the US (3) and the already high rate in Brazil, this is bound to create a significant public health problem. When questioning women's fears and expectations from cesarean section, pain during and after it is their greatest concern. (4) Individual variability in severity of pain after vaginal or operative delivery is influenced by multiple factors including sensitivity to pain, psychological factors, age, and genetics. The unique birth experience leads to unpredictable requirements for analgesics, from 'none at all' to 'very high' doses of pain medication. Pain after cesarean section is an excellent model to study post-operative pain because it is performed on otherwise young and healthy women. Therefore, it is recommended to attenuate the pain during the acute phase because this may lead to chronic pain disorders. The impact of developing persistent pain is immense, since it may impair not only the ability of women to care for their child in the immediate postpartum period, but also their own well being for a long period of time. In a series of projects, an international research network is currently investigating the effect of pregnancy on pain modulation and ways to predict who will suffer acute severe pain and potentially chronic pain, by using simple pain tests and questionnaires in combination with genetic analysis. A relatively recent approach to investigate pain modulation is via the psychophysical measure of Diffuse Noxious Inhibitory Control (DNIC). This pain-modulating process is the neurophysiological basis for the well-known phenomenon of 'pain inhibits pain' from remote areas of the body. The DNIC paradigm has evolved recently into a clinical tool and simple test and has been shown to be a predictor of post-operative pain.(5) Since pregnancy is associated with decreased pain sensitivity and/or enhanced processes of pain modulation, using tests that investigate pain modulation should provide a better understanding of the pathways involved with pregnancy-induced analgesia and may help predict pain outcomes during labor and delivery. For those women delivering by cesarean section, a DNIC test performed prior to surgery along with psychosocial questionnaires and genetic tests should enable one to identify women prone to suffer severe post-cesarean pain and persistent pain. These clinical tests should allow anesthesiologists to offer not only personalized medicine to women with the promise to improve well-being and satisfaction, but also a reduction in the overall cost of perioperative and long term care due to pain and suffering. On a larger scale, these tests that explore pain modulation may become bedside screening tests to predict the development of pain disorders following surgery.

    View details for DOI 10.3791/1671

    View details for PubMedID 20107427

  • Analgesic requirements and postoperative recovery after scheduled compared to unplanned cesarean delivery: a retrospective chart review INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Coleman, L., Saxena, A., Fuller, A. J., Riley, E. T. 2010; 19 (1): 10-15

    Abstract

    Studies examining the effects of various analgesics and anesthetics on postoperative pain following cesarean delivery conventionally use the scheduled cesarean population. This study compares postoperative analgesic requirements and recovery profiles in women undergoing scheduled cesarean compared to unplanned cesarean delivery following labor. We postulated that unplanned cesarean deliveries may increase postoperative analgesic requirements.We conducted a retrospective chart review of 200 cesarean deliveries at Lucile Packard Children's Hospital, California. We examined the records of 100 patients who underwent scheduled cesarean delivery under spinal anesthesia (hyperbaric bupivacaine 12 mg with intrathecal fentanyl 10 microg and morphine 200 microg) and 100 patients that following a trail of labor required unplanned cesarean under epidural anesthesia (10-25 mL 2% lidocaine top-up with epidural morphine 4 mg after clamping of the umbilical cord). We recorded pain scores, analgesic consumption, time to first analgesic request, side effects, and length of hospital stay.We found no differences in postoperative pain scores and analgesic consumption between scheduled and unplanned cesarean deliveries for up to five days postoperatively. There were no differences in treatment of side effects such as nausea, vomiting, or pruritus (P>0.05).The results indicate that women experience similar pain and analgesic requirements after scheduled compared to unplanned cesarean delivery. This suggests that the non-scheduled cesarean population may be a suitable pain model to study pain management strategies; and that alterations in pain management are not necessary for the unplanned cesarean delivery population.

    View details for DOI 10.1016/j.ijoa.2009.02.012

    View details for Web of Science ID 000273845400004

    View details for PubMedID 19954964

  • Elevation of Uterine Basal Tone and Fetal Heart Rate Abnormalities After Labor Analgesia: A Randomized Controlled Trial OBSTETRICS AND GYNECOLOGY Landau, R., Carvalho, B., Wong, C., Smiley, R., Tsen, L., Van de Velde, M. 2009; 113 (6): 1374-1374

    View details for Web of Science ID 000266392400037

    View details for PubMedID 19461449

  • Hetastarch co-loading is as effective as pre-loading for the prevention of hypotension following spinal anesthesia for cesarean delivery INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Mercier, F. J., Riley, E. T., Brummel, C., Cohen, S. E. 2009; 18 (2): 150-155

    Abstract

    Pre-loading with hetastarch decreases the incidence and severity of hypotension after spinal anesthesia for cesarean delivery. However, pharmacokinetic studies with crystalloid predict that fluid loading should be more efficacious if rapidly administered immediately after induction of spinal anesthesia. The aim of this study was to compare pre- and co-loading of hetastarch for the prevention of hypotension following spinal anesthesia for cesarean delivery.Forty-six healthy term parturients scheduled for cesarean delivery were randomized to receive 500 mL of 6% hetastarch intravenously, either slowly before spinal anesthesia (pre-loading) or as quickly as possible immediately after spinal anesthesia (co-loading). Systolic blood pressure was maintained at or above 90% of baseline with intravenous vasopressor boluses (ephedrine 5mg/mL+phenylephrine 25 microg/mL). The primary outcome was the volume of vasopressor mix required. Secondary outcomes included blood pressure and heart rate changes, time to first vasopressor use, nausea or vomiting, and neonatal outcomes (umbilical artery and vein pH, Apgar scores).The pre-loading group used 3.5+/-2 mL (mean+/-SD) of vasopressor mixture compared with 3.2+/-3 mL in the co-loading group (P=0.6). There were no differences in any important maternal hemodynamic or neonatal outcome values between the two study groups.Hetastarch co-loading is as effective as pre-loading for the prevention of hypotension after spinal anesthesia for cesarean delivery. Surgery need not be delayed to allow a predetermined pre-load to be administered before induction of spinal anesthesia.

    View details for DOI 10.1016/j.ijoa.2008.12.006

    View details for Web of Science ID 000265542200009

    View details for PubMedID 19223168

  • Patient-Controlled Epidural Analgesia for Labor ANESTHESIA AND ANALGESIA Halpern, S. H., Carvalho, B. 2009; 108 (3): 921-928

    Abstract

    Patient-controlled epidural analgesia (PCEA) for labor was introduced into clinical practice 20 yr ago. The PCEA technique has been shown to have significant benefits when compared with continuous epidural infusion. We conducted a systematic review using MEDLINE and EMBASE (1988-April 1, 2008) of all randomized, controlled trials in parturients who received PCEA in labor in which one of the following comparisons were made: background infusion versus none; ropivacaine versus bupivacaine; high versus low concentrations of local anesthetics; and new strategies versus standard strategies. The outcomes of interest were maternal analgesia, satisfaction, motor block, and the incidence of unscheduled clinician interventions. A continuous background infusion improved maternal analgesia and reduced unscheduled clinician interventions. Larger bolus doses (more than 5 mL) may provide better analgesia compared with small boluses. Low concentrations of bupivacaine or ropivacaine provide excellent analgesia without significant motor block. Many strategies with PCEA can provide effective labor analgesia. High volume, dilute local anesthetic solutions with a continuous background infusion appear to be the most successful strategy. Research into new delivery strategies, such as mandatory programmed intermittent boluses and computerized feedback dosing, is ongoing.

    View details for DOI 10.1213/ane.0b013e3181951a7f

    View details for Web of Science ID 000263537300041

    View details for PubMedID 19224805

  • Determining heat and mechanical pain threshold in inflamed skin of human subjects. Journal of visualized experiments : JoVE Angst, M. S., Tingle, M., Phillips, N. G., Carvalho, B. 2009

    Abstract

    In a previous article in the Journal of Visualized Experiments we have demonstrated skin microdialysis techniques for the collection of tissue-specific nociceptive and inflammatory biochemicals in humans. In this article we will show pain-testing paradigms that are often used in tandem with microdialysis procedures. Combining pain tests with microdialysis provides the critical link between behavioral and biochemical data that allows identifying key biochemicals responsible for generating and propagating pain. Two models of evoking pain in inflamed skin of human study participants are shown. The first model evokes pain with aid of heat stimuli. Heat evoked pain as described here is predominantly mediated by small, non-myelinated peripheral nociceptive nerve fibers (C-fibers). The second model evokes pain via punctuated pressure stimuli. Punctuated pressure evoked pain is predominantly mediated by small, myelinated peripheral nociceptive nerve fibers (A-delta fibers). The two models are mechanistically distinct and independently examine nociceptive processing by the two major peripheral nerve fiber populations involved in pain signaling. Heat pain is evoked with aid of the TSA II, a commercially available thermo-sensory analyzer (Medoc Advanced Medical Systems, Durham, NC). Stimulus configuration and delivery is handled with aid of specific software. Thermodes vary in size and shape but in principle consist of a metal plate that can be heated or cooled at various rates and for different periods of time. Algorithms assessing heat-evoked pain are manifold. In the experiments shown here, study participants are asked to indicate at what point they start experiencing pain while the thermode in contact with skin is heated at a predetermined rate starting at a temperature that does not evoke pain. The thermode temperature at which a subject starts experiencing pain constitutes the heat pain threshold. Mechanical pain is evoked with punctuated probes. Such probes are commercially available from several manufacturers (von Frey hairs). However, the accuracy of von Frey hairs has been criticized and many investigators use custom made punctuated pressure probes. In the experiments shown here eight custom-made punctuated probes of different weights are applied in consecutive order, a procedure called up-down algorithm, to identify perceptional deflection points, i.e., a change from feeling no pain to feeling pain or vice versa. The average weight causing a perceptional deflection constitutes the mechanical pain threshold.

    View details for DOI 10.3791/1092

    View details for PubMedID 19229176

  • A survey of perioperative and postoperative anesthetic practices for cesarean delivery. Anesthesiology research and practice Aiono-Le Tagaloa, L., Butwick, A. J., Carvalho, B. 2009; 2009: 510642-?

    Abstract

    The aim of this survey was to review cesarean delivery anesthetic practices. An online survey was sent to members of the Society of Obstetric Anesthesia and Perinatology (SOAP). The mode of anesthesia, preferred neuraxial local anesthetic and opioid agents, postoperative analgesic regimens, and monitoring modalities were assessed. 384 responses from 1,081 online survey requests were received (response rate = 36%). Spinal anesthesia is most commonly used for elective cesarean delivery (85% respondents), with 90% of these respondents preferring hyperbaric bupivacaine 0.75%. 79% used intrathecal fentanyl and 77% used morphine (median [range] dose 200 mcg [50-400]). 91% use respiratory rate, 61% use sedation scores, and 30% use pulse oximetry to monitor for postoperative respiratory depression after administration of neuraxial opioids. Postoperative analgesic regimens include: nonsteroidal anti-inflammatory agents, acetaminophen, oxycodone, and hydrocodone by 81%, 45%, 25%, and 27% respondents respectively. The majority of respondents use spinal anesthesia and neuraxial opioids for cesarean delivery anesthesia. There is marked variability in practices for monitoring respiratory depression postdelivery and for providing postoperative analgesia. These results may not be indicative of overall practice in the United States due to the select group of anesthesiologists surveyed and the low response rate.

    View details for DOI 10.1155/2009/510642

    View details for PubMedID 21217809

    View details for PubMedCentralID PMC2915619

  • Accidental intrathecal sufentanil overdose during combined spinal-epidural analgesia for labor INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Coleman, L., Carvalho, B., Lipman, S., Schmiesing, C., Riley, E. 2009; 18 (1): 78-80

    Abstract

    A laboring woman was accidentally given 45 microg of sufentanil intrathecally in the course of combined spinal-epidural analgesia. She experienced intense pruritus and transient swallowing difficulty without respiratory depression, but still had incomplete pain relief, with delivery and episiotomy repair requiring additional analgesia. This case highlights the importance of adding local anesthetic to intrathecal opioids to facilitate effective analgesia during the second stage of labor. The contributory systems issues and multiple factors that allowed this error to occur are examined.

    View details for DOI 10.1016/j.ijoa.2008.10.001

    View details for Web of Science ID 000262736700017

    View details for PubMedID 19111229

  • A Randomized Trial of Maximum Cephalad Sensory Blockade with Single-Shot Spinal Compared with Combined Spinal-Epidural Techniques for Cesarean Delivery 39th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Horstman, D. J., Riley, E. T., Carvalho, B. LIPPINCOTT WILLIAMS & WILKINS. 2009: 240–45

    Abstract

    Previous studies have shown more extensive cephalad sensory blockade in women receiving combined spinal-epidural (CSE) anesthesia compared with single-shot spinal (SSS) anesthesia for elective cesarean delivery. It has been postulated that introduction of the epidural needle during CSE disturbs the negative pressure in the epidural space, resulting in relatively greater cerebrospinal fluid (CSF) pressure and increased spread of intrathecal local anesthetic. We tested the hypothesis that CSE results in more extensive cephalad sensory blockade than SSS anesthesia and that loss-of-resistance during initiation of CSE anesthesia increases CSF pressure compared with SSS.Thirty parturients scheduled for elective cesarean delivery were enrolled in this randomized, double-blind study. Patients received either SSS or CSE anesthesia with equal doses of intrathecal anesthetic (hyperbaric bupivacaine 12 mg, fentanyl 10 microg and morphine 200 microg). Before the intrathecal injection, the CSF pressure was measured with a fiberoptic pressure sensor. Maximum cephalad sensory blockade to pinprick, cold and touch was measured. The total dose of phenylephrine required to maintain baseline arterial blood pressure was also recorded.There were no significant differences in the median (interquartile range) pinprick sensory block height [T4 (T4-2) vs T3 (T4-1)] or CSF pressures [6 (4-12) vs 9 (8-12) mm Hg] between the SSS and CSE groups. There were no significant correlations between CSF pressure and block height or total dose of phenylephrine.The SSS and CSE techniques inserted in the lateral decubitus position resulted in similar extent of sensory blockade and CSF pressure. These findings suggest that altering the intrathecal dose is not necessary and that any difference in intrathecal pressure associated with initial placement of an epidural needle in the epidural space during CSE anesthesia is clinically inconsequential.

    View details for DOI 10.1213/ane.0b013e31818e0fa6

    View details for Web of Science ID 000261963000037

    View details for PubMedID 19095857

  • Epidural labor analgesia in a patient receiving fondaparinux INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Tagaloa, L. A., Carvalho, B. 2009; 18 (1): 94-95

    View details for DOI 10.1016/j.ijoa.2008.07.007

    View details for Web of Science ID 000262736700026

    View details for PubMedID 19046870

  • Cytokine profile in human skin in response to experimental inflammation, noxious stimulation, and administration of a COX-inhibitor: A microdialysis study PAIN Angst, M. S., Clark, J. D., Carvalho, B., Tingle, M., Schmelz, M., Yeomans, D. C. 2008; 139 (1): 15-27

    Abstract

    Animal studies have documented a critical role for cytokines in cell signaling events underlying inflammation and pain associated with tissue injury. While clinical reports indicate an important role of cytokines in inflammatory pain, methodological limitations have made systematic human studies difficult. This study examined the utility of a human in vivo bioassay combining microdialysis with multiplex immunoassay techniques for measuring cytokine arrays in tissue. The first experiment measured cytokines in interstitial fluid collected from non-inflamed and experimentally inflamed skin (UVB). The effects of noxious heat on cytokine release were also assessed. The second experiment examined whether anti-hyperalgesic effects of the COX-inhibitor ibuprofen were associated with decreased tissue levels of the pro-inflammatory cytokines IL-1 beta and IL-6. In the first experiment, inflammation significantly increased IL-1 beta, IL-6, IL-8, IL-10, G-CSF, and MIP-1 beta. Noxious heat but not experimental inflammation significantly increased IL-7 and IL-13. In the second experiment, an oral dose of 400 and 800 mg ibuprofen produced similar anti-hyperalgesic effects suggesting a ceiling effect. Tissue levels of IL-1 beta and IL-6 were not affected after the 400mg dose but decreased significantly (44+/-32% and 38+/-13%) after the 800 mg dose. These results support the utility of explored method for tracking cytokines in human tissue and suggest that anti-hyperalgesic and anti-inflammatory effects of ibuprofen are at least partially dissociated. The data further suggest that high clinical doses of ibuprofen exert anti-inflammatory effects by down-regulating tissue cytokine levels. Explored human bioassay is a promising tool for studying the pathology and pharmacology of inflammatory and chronic pain conditions.

    View details for DOI 10.1016/j.pain.2008.02.028

    View details for PubMedID 18396374

  • Respiratory depression after neuraxial opioids in the obstetric setting ANESTHESIA AND ANALGESIA Carvalho, B. 2008; 107 (3): 956-961

    Abstract

    Neuraxial opioids have contributed significantly to improved labor and postcesarean delivery analgesia. In the obstetric population, epidural and intrathecal opioids are associated with a very low risk of clinically significant respiratory depression. Although rare, respiratory depression is a serious risk; patients may die or suffer permanent brain damage as a consequence. This review discusses the mechanism and incidence, as well as the prevention, detection, and management of respiratory depression with morphine, extended-release epidural morphine, and lipophilic opioids in the labor and cesarean delivery setting.

    View details for DOI 10.1213/ane.0b013e318168b443

    View details for Web of Science ID 000258702500041

    View details for PubMedID 18713913

  • Vaginal twin delivery: a survey and review of location, anesthesia coverage and interventions 38th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Carvalho, B., Saxena, A., Butwick, A., Macario, A. CHURCHILL LIVINGSTONE. 2008: 212–16

    Abstract

    Twin pregnancies are associated with increased perinatal morbidity and mortality. No consensus exists whether vaginal twin delivery should take place in the labor room or operating room, or whether anesthesiologists should be present. We surveyed members of the California Society of Anesthesiologists (CSA) to review management of vaginal twin delivery, and examined anesthetic intervention retrospectively at our institution.230 CSA members were asked to complete an online survey on location of vaginal twin delivery in their institution and whether they were required to be present throughout. We then retrospectively reviewed charts of vaginal twin deliveries at our institution over a 36-month period to analyze frequency and type of anesthetic intervention.The online survey response rate was 58%; 64% of responders reported that vaginal twin deliveries were performed in the operating room and 55% that an anesthesiologist was present. There was a strong association between anesthesiologist's presence and delivery in the operating room (OR 7; 95% CI 3-20). We reviewed 81 charts of women who underwent vaginal twin delivery. The median (range) time that the anesthesiologist was present for each delivery was 60 (20-380) min. Of women undergoing vaginal twin delivery, 27% required anesthetic intervention during the second stage of labor with 6% having emergency cesarean delivery.There is a lack of consensus regarding the appropriate location for vaginal twin delivery and the role of anesthesiologists. A significant percentage of women undergoing vaginal twin delivery in our institution received anesthetic intervention in the immediate delivery period.

    View details for DOI 10.1016/j.ijoa.2007.04.004

    View details for Web of Science ID 000257844200003

    View details for PubMedID 17881218

  • Local and systemic release of cytokines, nerve growth factor, prostaglandin E2, and substance P in incisional wounds and serum following cesarean delivery JOURNAL OF PAIN Carvalho, B., Clark, D. J., Angst, M. S. 2008; 9 (7): 650-657

    Abstract

    The objectives of this study were to test the feasibility of measuring inflammatory and nociceptive biochemical mediators at the surgical site and to evaluate the relationship between wound and serum levels as well as determine any associations between mediator release, pain, and analgesic consumption after cesarean delivery. Twenty healthy women undergoing elective cesarean delivery with spinal anesthesia were enrolled. Wound exudate and serum mediators, pain scores, and analgesic consumption were measured at 1, 6, 24, and 48 hours after cesarean. In wound exudate, 19 of 20 mediators were reliably detected including interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, tumor necrosis factor-alpha, interferon-gamma, granulocyte colony stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF), monocyte chemoattractant protein 1 (MCP-1) and macrophage inflammatory protein 1 (MIP-1beta), nerve growth factor (NGF), prostaglandin E2 (PG-E2), and substance P. Wound PG-E2 and various cytokines peaked early, whereas NGF showed a more delayed release. There were no correlations between the concentration versus time profile of wound and serum cytokines. Analgesic consumption during the first 24 hours after surgery was negatively correlated with IL-1beta, IL-6, and G-CSF in the wound exudate. This study demonstrates the feasibility of collecting and measuring nociceptive and inflammatory mediators in surgical wounds at specific time points. The lack of significant correlations between wound and serum levels emphasizes the importance of determining site-specific release if localized pathologies are to be studied.This study demonstrates the feasibility of measuring real-time nociceptive and inflammatory mediators in surgical wounds. Our findings confirm the lack of correlation between wound and serum levels of many pro-inflammatory and anti-inflammatory cytokines and nerve growth factor.

    View details for DOI 10.1016/j.jpain.2008.02.004

    View details for PubMedID 18394968

  • Labor and cesarean delivery patterns ANESTHESIOLOGY Carvalho, B. 2008; 109 (1): 161-162

    View details for Web of Science ID 000257135300035

    View details for PubMedID 18580198

  • Strategies to comply with the five-minute rule after maternal arrest INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Mhyre, J. M. 2008; 17 (3): 284-285

    View details for DOI 10.1016/j.ijoa.2008.03.004

    View details for Web of Science ID 000257844200022

    View details for PubMedID 18511259

  • Assessment of knowledge regarding cardiopulmonary resuscitation of pregnant women INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Cohen, S. E., Andes, L. C., Carvalho, B. 2008; 17 (1): 20-25

    Abstract

    The 2000-2002 triennial UK Report on Confidential Enquiries into Maternal Deaths concluded that over 50% of maternal deaths involved substandard care and that many could have been prevented. Catastrophic events leading to cardio-respiratory arrest may necessitate the resuscitation of pregnant women in various hospital locations. This study was designed to evaluate knowledge about resuscitation of parturients among anesthesiologists, obstetricians and emergency physicians.A 12-question survey was distributed anonymously to residents and faculty in the anesthesia (ANES), obstetrics (OB), and emergency medicine (EM) departments at Stanford University Medical Center/Lucile Packard Children's Hospital, Stanford, California. Questions were designed to elicit knowledge deficiencies in four critical areas: need for left uterine displacement (LUD), advanced cardiac life support algorithms (ACLS), physiologic changes of pregnancy (PHYS), and the recommendation to perform cesarean delivery in parturients (>20 weeks gestation) after 4-5 min of unsuccessful resuscitation for cardiac arrest (5CD).In total, 74/75 physicians (43% ANES, 37% OB, and 20% EM) completed the test. ANES scored highest in overall test scores, and in knowledge of PHYS (P<0.05). Scores for LUD and 5CD were similar among groups, but 25-40% of these questions were answered incorrectly. In the ACLS category, the EM group scored highest (93%).We conclude that knowledge of important basic concepts, including the need for LUD and the potential benefit of early cesarean delivery during cardiac arrest, is inadequate among all three specialties. All three departments should provide ACLS physician training with emphasis on the special considerations for parturients.

    View details for DOI 10.1016/j.ijoa.2007.10.002

    View details for Web of Science ID 000253167900005

    View details for PubMedID 18162200

  • Human in-vivo bioassay for the tissue-specific measurement of nociceptive and inflammatory mediators. Journal of visualized experiments : JoVE Angst, M. S., Tingle, M., Schmelz, M., Carvalho, B., Yeomans, D. C. 2008

    Abstract

    This in-vivo human bioassay can be used to study human volunteers and patients. Samples are collected from pertinent tissue sites such as the skin via aseptically inserted microdialysis catheters (Dermal Dialysis, Erlangen, Germany). Illustrated in this example is the collection of interstitial fluid from experimentally inflamed skin in human volunteers. Sample collection can be combined with other experimental tests. For example, the simultaneous assessment of locally released biochemicals and subjective sensitivity to painful stimuli in experimentally inflamed skin provides the critical biochemical-behavioral link to identify biomarkers of pain and inflammation. Presented assay in the living human organism allows for mechanistic insight into tissue-specific processes underlying pain and/or inflammation. The method is also well suited to examine the effectiveness of existing or novel interventions--such as new drug candidates - targeting the treatment of painful and/or inflammatory conditions. This article will provide a detailed description on the use of microdialysis techniques for collecting interstitial fluid from experimentally inflamed skin lesion of human study subjects. Interstitial fluid samples are typically processed with aid of multiplex bead array immunoassays allowing assaying up to 100 analytes in samples as small in volume as 50 microliters.

    View details for DOI 10.3791/1074

    View details for PubMedID 19229167

  • Collecting and measuring nociceptive and inflammatory mediators in surgical wounds. Journal of visualized experiments : JoVE Carvalho, B., Clark, D. J., Yeomans, D., Angst, M. S. 2008

    Abstract

    We describe a methodology by which we are able to collect and measure inflammatory and nociceptive biochemical mediators at the surgical wound site. Collecting site-specific biochemical markers allows us to evaluate the relationship between surgical wound and serum levels;determine any associations between mediator release, pain and analgesic consumption; and evaluate the effect of systemic and peripheral drug administration on surgical wound biochemistry.This methodology has been applied to healthy women undergoing elective cesarean delivery with spinal anesthesia. Wound exudate and serum mediators, in conjunction with pain scores and analgesics consumption were measured at 1, 6, 24, and 48 hours post-cesarean delivery.Biochemical mediators that were detected included IL-1β, IL-2, IL-4, IL-6, IL-7, IL-8, IL-10, IL-12, IL-13, IL-17, TNFα, INFγ, G-CSF, GM-CSF,MCP-1 and MIP-1β, nerve growth factor (NGF), prostaglandin E2 (PG-E2) and substance P. We found no correlations between wound and serum cytokines concentrations or time-release profiles (J Pain. 2008 Jul 9(7):650-7). This article describes and demonstrates the feasibility of collecting and assaying nociceptive and inflammatory mediators in surgical wounds at specific time points. The lack of significant correlations between serum and wound levels shows the importance of determining site-specific release if surgical wounds and localized pathologies are to be studied [corrected].

    View details for DOI 10.3791/962

    View details for PubMedID 19078937

  • Extended release epidural morphine, far from ideal for postcesarean delivery pain control ANESTHESIA AND ANALGESIA Roboubi, B. 2007; 105 (6): 1864-1864

    View details for Web of Science ID 000251274400063

    View details for PubMedID 18042899

  • Intraoperative forced air-warming during cesarean delivery under spinal anesthesia does not prevent maternal hypothermia ANESTHESIA AND ANALGESIA Butwick, A. J., Lipman, S. S., Carvalho, B. 2007; 105 (5): 1413-1419

    Abstract

    Prewarming and intraoperative warming with forced air-warming systems prevent perioperative hypothermia and shivering in patients undergoing elective cesarean delivery with epidural anesthesia. We tested the hypothesis that intraoperative lower body forced air-warming prevents hypothermia in patients undergoing elective cesarean delivery with spinal anesthesia.Thirty healthy patients undergoing cesarean delivery with spinal anesthesia were randomly assigned to forced air-warming or control groups (identical cover applied with forced air-warming unit switched off). A blinded investigator assessed oral temperature, shivering, and thermal comfort scores at 15-min intervals until discharge from the postanesthetic care unit. Umbilical cord blood gases and Apgar scores were also measured after delivery.The maximum core temperature changes were similar in the two groups (-1.3 degrees C +/- 0.4 degrees C vs -1.3 degrees C +/- 0.3 degrees C for the forced air-warming group and control group, respectively; P = 0.8). Core hypothermia (< or =35.5 degrees C) occurred in 8 of 15 patients receiving forced air-warming and in 10 of 15 unwarmed patients (P = 0.5). The incidence and severity of shivering did not significantly differ between groups. Umbilical cord blood gases and Apgar scores were similar in both groups (P = NS).We conclude that intraoperative lower body forced air-warming does not prevent intraoperative hypothermia or shivering in women undergoing elective cesarean delivery with spinal anesthesia.

    View details for DOI 10.1213/01.ane.0000286167.96410.27

    View details for Web of Science ID 000250317500039

    View details for PubMedID 17959975

  • Can we improve maternal outcome for high-risk obstetric patients? INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B. 2007; 16 (4): 311-313

    View details for DOI 10.1016/j.ijoa.2007.04.005

    View details for Web of Science ID 000250284800003

    View details for PubMedID 17698338

  • Plasma and wound exudate cytokine, prostaglandin E2, substance P and nerve growth factor release following Cesarean delivery Carvalho, B., Clark, D., Angst, M. MARY ANN LIEBERT INC. 2007: 1103–
  • The Episure (TM) syringe: A novel loss of resistance syringe for locating the epidural space 37th Annual Meeting of the Society-of-Obstetric-Anesthesiology-and-Perinatology Riley, E. T., Carvalho, B. LIPPINCOTT WILLIAMS & WILKINS. 2007: 1164–66

    Abstract

    The Episure syringe is a unique spring-loaded loss-of-resistance (LOR) syringe with a coaxial compression spring within a Portex Pulsator LOR syringe. This syringe supplies a constant pressure while the operator is advancing the Tuohy needle.We evaluated the syringe using an artificial model of the ligamentum flavum, an anesthetized pig, and women who desired epidural analgesia for labor.The operator, using the spring-loaded syringe, was able to stop the forward movement of the needle, so that compared with a standard LOR syringe less of the needle protruded out the back of the laboratory model. Satisfactory labor analgesia in the human study and radiograph analyses in the porcine model confirmed epidural placement in all attempts.The spring-loaded syringe is a potentially useful LOR syringe that provides a reliable, objective end-point for identification of the epidural space.

    View details for DOI 10.1213/01.ane.0000281935.78144.82

    View details for Web of Science ID 000249678500043

    View details for PubMedID 17898406

  • Fetal oxygen saturation after combined spinal-epidural Labor analgesia: a case series JOURNAL OF CLINICAL ANESTHESIA Carvalho, B., Fuller, A. I., Brummel, C., Durbin, M., Riley, E. T. 2007; 19 (6): 476-478

    Abstract

    Fetal oxygen saturation (FSpo(2)) is an emerging technology for intrapartum fetal monitoring. We monitored FSpo(2) before and after combined spinal-epidural analgesia in 8 laboring women requesting neuraxial analgesia. Fetal heart rate (FHR) and FSpo(2) (using the Nellcor N400/FS14 system [Nellcor, Pleasanton, CA]) were recorded at baseline and every minute for 45 minutes after analgesia. We observed no significant changes in FSpo(2) after analgesia (mean DeltaFSpo(2) 2 +/- 7 %, P = 0.46). Fetal oxygen saturation at baseline and after analgesia was 53% +/- 9% and 51% +/- 8%, respectively. We observed no significant FHR changes or any fetal bradycardia following combined spinal-epidural analgesia.

    View details for DOI 10.1016/j.jclinane.2007.01.009

    View details for Web of Science ID 000250817600017

    View details for PubMedID 17967682

  • Single-dose, extended-release epidural morphine (DepoDur (TM)) compared to conventional epidural morphine for post-cesarean pain ANESTHESIA AND ANALGESIA Carvalho, B., Roland, L. M., Chu, L. F., Campitelli, V. A., Riley, E. T. 2007; 105 (1): 176-183

    Abstract

    A single-dose of neuraxial morphine sulfate provides good post-Cesarean analgesia; however, its efficacy is limited to the first postoperative day. In a recent phase III study, extended-release epidural morphine (EREM) formulation provided more effective, prolonged analgesia after Cesarean delivery, compared to conventional epidural morphine. However, the study protocol did not allow for the use of nonsteroidal antiinflammatory drugs, used various postoperative analgesics, and monitoring and treatment of respiratory depression were not standardized. Our aims in this study were to compare postoperative analgesic consumption, pain scores and side effects of EREM with conventional morphine for the management of post-Cesarean pain in a setting more reflective of current obstetric practice.Seventy healthy parturients undergoing elective Cesarean delivery were enrolled in this randomized, double-blind study. Using a combined spinal epidural technique, patients received an intrathecal injection of bupivacaine 12 mg and fentanyl 10 mcg. After closure of the fascia, a single-dose of either conventional morphine 4 mg or EREM 10 mg was administered epidurally. Postoperatively, all patients received ibuprofen 600 mg orally every 6 h. Oral oxycodone and IV morphine were available for breakthrough pain. All patients received pulse oximetry and respiratory monitoring for 48 h post-Cesarean delivery.Single-dose EREM significantly improved pain scores at rest and during activity. The median (interquartile range) of supplemental opioid medication usage for 48 h post-Cesarean (in milligram-morphine equivalents) decreased from 17 (22) to 10 (17) mg with EREM compared to conventional epidural morphine (P = 0.037). Both drugs were well tolerated with no significant difference in adverse event profiles.EREM provides superior and prolonged post-Cesarean analgesia compared to conventional epidural morphine with no significant increases in adverse events.

    View details for DOI 10.1213/01.ane.0000265533.13477.26

    View details for PubMedID 17578973

  • Neuraxial anesthesia for cesarean delivery in a parturient with type 1 von Willebrand disease and scoliosis JOURNAL OF CLINICAL ANESTHESIA Butwick, A. J., Carvalho, B. 2007; 19 (3): 230-233

    Abstract

    We present the case of a parturient with von Willebrand disease and scoliosis who required cesarean delivery. Neuraxial anesthesia was used for the patient. The indications for neuraxial anesthesia with regard to type 1 von Willebrand disease are reviewed.

    View details for DOI 10.1016/j.jclinane.2006.08.013

    View details for Web of Science ID 000247128200014

    View details for PubMedID 17531735

  • A cost-analysis of neuraxial analgesia to facilitate external cephalic version 39th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Tan, J. M., Macario, A., El-Sayed, Y., Carvalho, B. LIPPINCOTT WILLIAMS & WILKINS. 2007: B53–B53
  • Is external cephalic version cost-effective? 39th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Tan, J. M., Macario, A., Carvalho, B., El-Sayed, Y. LIPPINCOTT WILLIAMS & WILKINS. 2007: B16–B16
  • Incisional wound and systemic cytokines release following cesarean section 39th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Carvalho, B., Clark, D., Angst, M. LIPPINCOTT WILLIAMS & WILKINS. 2007: B43–B43
  • Plasma and wound exudate prostaglandin E2 and substance P release following cesarean section 39th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Carvalho, B., Angst, M., Clark, D. LIPPINCOTT WILLIAMS & WILKINS. 2007: B19–B19
  • Local infiltration of epinephrine-containing lidocaine with bicarbonate reduces superficial bleeding and pain during labor epidural catheter insertion: a randomized trial INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Fuller, A., Brummel, C., Cohen, S. E. 2007; 16 (2): 116-121

    Abstract

    Superficial bleeding after labor epidural catheter placement is a common phenomenon. In addition to delaying securing the epidural catheter, it may loosen the adhesive catheter dressing. The primary aim of this study was to determine whether skin infiltration with epinephrine-containing rather than plain lidocaine reduces superficial bleeding after catheter placement. Secondary objectives were to determine whether adding epinephrine and/or sodium bicarbonate affected infiltration pain.After institutional review board approval and informed consent, 80 healthy women receiving epidural analgesia during labor were randomly assigned in a double-blind manner to four local anesthetic mixtures (n=20 in each group): group L: lidocaine 1.5%, group LB: lidocaine 1.5% with 8.4% sodium bicarbonate, group LE: lidocaine 1.5% with epinephrine 1:200000, and group LEB: lidocaine 1.5% with epinephrine 1:200000 and 8.4% sodium bicarbonate. Clinical endpoints included the amount of superficial bleeding at the catheter site, pain during local anesthetic infiltration and epidural catheter movement during labor.Demographic data were similar among the groups. The addition of epinephrine to lidocaine significantly reduced superficial bleeding. Solutions containing epinephrine were well tolerated and caused no cardiovascular disturbances. The addition of epinephrine did not increase pain, while bicarbonate reduced it [verbal score (scale 0-10) 3.6+/-2.2 vs. 2.6+/-1.8; P=0.04]. There were no differences in epidural catheter movement among the groups; no catheters became displaced during labor.Local infiltration of epinephrine-containing lidocaine before epidural catheter insertion reduces superficial bleeding and the addition of bicarbonate decreases pain during skin infiltration.

    View details for DOI 10.1016/j.ijoa.2006.09.006

    View details for Web of Science ID 000245838800004

    View details for PubMedID 17276670

  • The effect of colloid and crystalloid preloading on thromboelastography prior to Cesarean delivery Annual Meeting of the Obstetric-Anaesthetists-Association Butwick, A., Carvalho, B. SPRINGER. 2007: 190–95

    Abstract

    Fluid preloading with colloids reduces hypotension after spinal anesthesia for Cesarean delivery more effectively than crystalloids. However, the effects of fluid preloading regimens on coagulation in pregnant patients remain unresolved. The aim of this study was to compare the effects on coagulation of fluid preloading with 6% hydroxyethyl starch (HES) and lactated Ringer's (LR) solution using thromboelastography (TEG) with kaolin-activated whole blood in healthy pregnant patients prior to spinal anesthesia for Cesarean delivery.After obtaining Ethics committee approval, 30 parturients were prospectively randomized prior to spinal anesthesia for elective Cesarean delivery to receive fluid preloading with either 1500 mL LR or 500 mL 6% HES over 30 min. Thromboelastography was performed immediately prior to and after fluid preloading. Standard TEG parameters were analyzed in terms of r time (min), k time (min), alpha angle (degrees) and maximum amplitude (mm).Group HES had statistically significant longer reaction times (r) and clot formation times (k) after fluid loading compared to baseline values (P < 0.05 respectively), although these post-fluid loading TEG parameters remained within a normal reference range. No significant differences in TEG values were seen after preloading within the LR group.Fluid preloading with 500 mL 6% HES in healthy parturients produced mild coagulation effects, as measured with TEG, prior to spinal anesthesia for Cesarean delivery. No significant effects on coagulation with TEG were observed following preloading with 1500 mL LR.

    View details for Web of Science ID 000245113600005

    View details for PubMedID 17331930

  • Experimental heat pain for detecting pregnancy-induced analgesia in humans ANESTHESIA AND ANALGESIA Carvalho, B., Angst, M. S., Fuller, A. J., Lin, E., Mathusamy, A. D., Riley, E. T. 2006; 103 (5): 1283-1287

    Abstract

    Animal studies suggest that increased circulating estrogen and progesterone, and activation of the endorphin system cause prenancy-induced antinociceptive effects. Human studies have provided inconsistent results and have often lacked a nonpregnant control group. In this study, we compared sensitivity to experimental heat and cold pain in pregnant and nonpregnant women. Nineteen healthy nonpregnant female volunteers and 20 pregnant women at term were enrolled. Pain threshold and tolerance were examined using experimental heat-induced pain and cold pressor pain models. Subjects were evaluated pre- and 1-2 days post-delivery (pregnant), or on consecutive days (nonpregnant). Heat pain tolerance was significantly increased in the pregnant women during pre and postdelivery when compared with nonpregnant controls (50.0 +/- 1.0 vs 49.0 +/- 1.2 and 50.1 +/- 0.7 vs 49.2 +/- 1.2 degrees C; mean +/- sd). However, pain induced by the cold pressor test was endured for a similar amount of time by both study groups. Pregnancy-induced analgesic effects at term can be detected in a model of experimental heat pain. These effects persist during the first 24-48 h after delivery. Experimental heat pain is a suitable modality for further characterizing the phenomenon of pregnancy-induced analgesia in humans.

    View details for DOI 10.1213/01.ane.0000239224.48719.28

    View details for PubMedID 17056970

  • Anesthesia for interventional radiology in parturients at risk of major hemorrhage at cesarean section delivery ANESTHESIA AND ANALGESIA Harnett, M. J., Carabuena, J. M., Tsen, L. C., Kodali, B. S. 2006; 103 (5): 1329-1330
  • Valdecoxib for postoperative pain management after cesarean delivery: A randomized, double-blind, placebo-controlled study 37th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Carvalho, B., Chu, L., Fuller, A., Cohen, S. E., Riley, E. T. LIPPINCOTT WILLIAMS & WILKINS. 2006: 664–70

    Abstract

    Although nonsteroidal antiinflammatory drugs (NSAIDs) improve postoperative pain relief after cesarean delivery, they carry potential side effects (e.g., bleeding). Perioperative cyclooxygenase (COX)-2 inhibitors show similar analgesic efficacy to nonsteroidal antiinflammatory drugs in many surgical models but have not been studied after cesarean delivery. We designed this randomized double-blind study to determine the analgesic efficacy and opioid-sparing effects of valdecoxib after cesarean delivery. Healthy patients undergoing elective cesarean delivery under spinal anesthesia were randomized to receive oral valdecoxib 20 mg or placebo every 12 h for 72 h postoperatively. As a result of cyclooxygenase-2 inhibitors safety concerns that became apparent during this study, the study was terminated early after evaluating 48 patients. We found no differences in total analgesic consumption between the valdecoxib and placebo groups (121 +/- 70 versus 143 +/- 77 morphine mg-equivalents, respectively; P = 0.26). Pain at rest and during activity were similar between the groups despite adequate post hoc power to have detected a clinically significant difference. There were also no differences in IV morphine requirements, time to first analgesic request, patient satisfaction, side effects, breast-feeding success, or functional activity. Postoperative pain was generally well controlled. Adding valdecoxib after cesarean delivery under spinal anesthesia with intrathecal morphine is not supported at this time.

    View details for DOI 10.1213/01.ane.0000229702.42426.a6

    View details for PubMedID 16931678

  • A survey of labor patient-controlled epidural anesthesia practice in California hospitals 37th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Carvalho, B., Wang, P., Cohen, S. E. ELSEVIER SCI LTD. 2006: 217–22

    Abstract

    Patient-controlled epidural analgesia (PCEA) offers many advantages over continuous epidural infusions for labor analgesia including fewer physician interventions, improved analgesia and satisfaction, and reduced local anesthetic doses. However, anesthesiologists have been slow to adopt this technique, first described in 1988. No previous studies have evaluated specific labor patient-controlled epidural analgesia practices in the United States. The aim of this study was to determine labor epidural and patient-controlled epidural analgesia practices among California hospitals.Following institutional review board exemption approval, an online survey was created using freeonlinesurveys.com. An anonymous survey was sent via e-mail to 230 California Society of Anesthesiologists' members chosen at random to represent their hospitals' labor analgesia practices.We received 133 replies from the 230 survey requests sent, a 58% response rate. The median labor epidural rate among the hospitals involved was 65% (range 0-95%). Overall, only 25% of California hospitals use patient-controlled epidural analgesia for analgesia in labor, with greater use among hospitals with dedicated obstetric anesthesia coverage and larger numbers of deliveries. Reasons given for not using patient-controlled epidural analgesia include cost, clinician preference, safety concerns and the inconvenience of change.Despite the potential advantages of patient-controlled epidural analgesia over continuous epidural infusions for labor analgesia, patient-controlled epidural analgesia has not been widely adopted in California hospitals. Education regarding this technique is needed to encourage its increased use.

    View details for DOI 10.1016/j.ijoa.2006.03.006

    View details for Web of Science ID 000239166100007

    View details for PubMedID 16798447

  • Solutions for patient-controlled epidural analgesia INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Paech, M. 2006; 15 (3): 262-262

    View details for DOI 10.1016/j.ijoa.2006.03.002

    View details for Web of Science ID 000239166100027

    View details for PubMedID 16798466

  • Epidural labor analgesia in a patient with pemphigoid gestationis 38th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Roland, L., Collins, J., Carvalho, B. LIPPINCOTT WILLIAMS & WILKINS. 2006: B53–B53
  • Epidural anesthesia for elective cesarean delivery with intraoperative arterial occlusion balloon catheter placement 36th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Fuller, A. J., Carvalho, B., Brummel, C., Riley, E. T. LIPPINCOTT WILLIAMS & WILKINS. 2006: 585–87

    Abstract

    Obstetric hemorrhage is a leading cause of maternal mortality. We describe the anesthetic management of elective cesarean delivery in patients at high risk for hemorrhage. The utility and limitations of intraarterial balloon catheter placement and epidural anesthesia are described.

    View details for DOI 10.1213/01.ane.0000189551.61937.ea

    View details for Web of Science ID 000234912900049

    View details for PubMedID 16428566

  • Remifentanil patient-controlled analgesia in labor ANESTHESIA AND ANALGESIA Butwick, A., Carvalho, B. 2006; 102 (1): 333-333

    View details for Web of Science ID 000234275700071

    View details for PubMedID 16368862

  • Nonobstetric surgery during pregnancy 80th Clinical and Scientific Congress of the International-Anesthesia-Research-Society Carvalho, B. LIPPINCOTT WILLIAMS & WILKINS. 2006: 23–30
  • Patient preferences for anesthesia outcomes associated with Cesarean delivery ANESTHESIA AND ANALGESIA Carvalho, B., Cohen, S. E., Lipman, S. S., Fuller, A., Mathusamy, A. D., Macario, A. 2005; 101 (4): 1182-1187

    Abstract

    When deciding on neuraxial medication (e.g., spinal opioids) for cesarean delivery (CS) under regional anesthesia, anesthesiologists make treatment decisions that "trade off" relieving pain with the potential for increased risk of side effects. No previous studies have examined obstetric patients' anesthesia preferences. Researchers administered 100 written surveys to pregnant women attending our institutions' expectant parent class. We determined patients' preferences for importance of specific intraoperative and postoperative anesthesia outcomes using priority ranking and relative value scales. We also explored patients' fears, concerns, and tolerance regarding CS and analgesics. Eighty-two of 100 surveys were returned and analyzed. Pain during and after CS was the greatest concern followed by vomiting, nausea, cramping, pruritus, and shivering. Ranking and relative value scores were closely correlated (R2 = 0.7). Patients would tolerate a visual analog pain score (0-100 mm) of 56 +/- 22 before exposing their baby to the potential effects of analgesics they receive. In contrast to previous general surgical population surveys that found nausea and vomiting as primary concerns, we found pain during and after CS as parturients' most important concern. Common side effects such as pruritus and shivering caused only moderate concern. This information should be used to guide anesthetic choices, e.g., inclusion of spinal opioids given in adequate doses.Medical care can be improved by incorporating patients' preferences into medical decision making. We surveyed obstetric patients to determine their preferences regarding potential cesarean delivery anesthesia outcomes. Unlike general surgical patients who rate nausea and vomiting highest, parturients considered pain during and after cesarean delivery the most important concern.

    View details for DOI 10.1213/01.ane.0000167774.36833.99

    View details for Web of Science ID 000232115400045

    View details for PubMedID 16192541

  • The ED50 and ED95 of intrathecal isobaric bupivacaine with opioids for cesarean delivery ANESTHESIOLOGY Carvalho, B., Durbin, M., Drover, D. R., Cohen, S. E., Ginosar, Y., Riley, E. T. 2005; 103 (3): 606-612

    Abstract

    The ideal intrathecal isobaric bupivacaine dose for cesarean delivery anesthesia is uncertain. While small doses (5-9 mg) of bupivacaine may reduce side effects such as hypotension, they potentially increase spinal anesthetic failures. This study determined the ED50 and ED95 of intrathecal isobaric bupivacaine (with adjuvant opioids) for cesarean delivery.After institutional review board approval and written informed consent were obtained, 48 parturients undergoing elective cesarean delivery under combined spinal-epidural anesthesia were enrolled in this double-blind, randomized, dose-ranging study. Patients received a 5-, 6-, 7-, 8-, 9-, 10-, 11-, or 12-mg intrathecal isobaric bupivacaine dose with 10 microg fentanyl and 200 microg morphine. Overall anesthetic success was recorded when no intraoperative epidural supplement was required during the cesarean delivery. ED50 and ED95 values for overall anesthetic success were determined using a logistic regression model.ED50 and ED95 values for overall anesthetic success were 7.25 and 13.0 mg, respectively. No advantages for low doses could be demonstrated with regard to hypotension, nausea, vomiting, pruritus, or maternal satisfaction, although this study was underpowered to detect significant differences in secondary outcome variables.The ED50 and ED95 values (7.25 and 13.0 mg, respectively) for intrathecal isobaric bupivacaine in this circumstance are similar to values the authors determined recently for hyperbaric bupivacaine using similar methodology. These ED50 and ED95 values are significantly higher than those advocated in previous reports in which success was claimed using lower intrathecal bupivacaine doses. The current study used stricter criteria to define "successful" anesthesia and support the use of larger bupivacaine doses to ensure adequate patient comfort.

    View details for PubMedID 16129987

  • "Ultra-light" patient-controlled epidural analgesia during labor: effects of varying regimens on analgesia and physician workload INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Cohen, S. E., Giarrusso, K., Durbin, M., Riley, E. T., Lipman, S. 2005; 14 (3): 223-229

    Abstract

    Patient-controlled epidural analgesia (PCEA) offers many advantages over continuous epidural infusions for maintenance of labor analgesia. Some of these benefits may depend on the PCEA settings. This study evaluated several regimens for "ultra-light" (0.125%) PCEA with basal continuous infusion (CI) in labor with goals of minimizing physician interventions while providing good analgesia.Two hundred and twenty ASA I-II women receiving epidural analgesia during active labor (cervical dilation <5 cm) were randomly assigned in a double-blind manner to four treatment groups (n=30 in each). Analgesia was maintained with a PCEA/CI pump using bupivacaine 0.0625% + sufentanil 0.35 microg/mL. PCEA settings were: group A: CI 10 mL/h, PCEA bolus 6 mL, 8-min lockout; group B: CI 10 mL/h, PCEA bolus 12 mL, 16-min lockout; group C: CI 15 mL/h, PCEA bolus 6 mL, 8-min lockout; group D: CI 15 mL/h, PCEA bolus 12 mL, 16-min lockout.In groups A, B, C and D, 76, 77, 75 and 85% of parturients respectively, required no physician rescue boluses. Pain scores were low and maternal satisfaction was high in all groups, with minimal differences among them. Spontaneous vaginal delivery occurred in 78% of patients overall, instrumental (forceps or vacuum) delivery in 10% and cesarean section in 12%.These ultra-light PCEA regimens provided excellent analgesia with minimal physician workload and a high spontaneous delivery rate. Use of moderate to high-volume, ultra-light PCEA/CI techniques should facilitate provision of labor analgesia in busy obstetric units.

    View details for DOI 10.1016/j.ijoa.2005.02.003

    View details for Web of Science ID 000230915700008

    View details for PubMedID 15935646

  • Valdecoxib for postoperative pain management after cesarean section: A randomized, double-blinded, placebo controlled study 37th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Fuller, A. J., Brummel, C., Saxena, A., Chu, L., Riley, E. T., Cohen, S. E., Carvalho, B. LIPPINCOTT WILLIAMS & WILKINS. 2005: A15–A15
  • A survey of labor patient-controlled epidural anesthesia practice in Californian hospitals 37th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Carvalho, B., Wang, P., Riley, E. T., Cohen, S. E. LIPPINCOTT WILLIAMS & WILKINS. 2005: A29–A29
  • Single-dose, sustained-release epidural morphine in the management of postoperative pain after elective Cesarean delivery: Results of a multicenter randomized controlled study ANESTHESIA AND ANALGESIA Carvalho, B., Riley, E., Cohen, S. E., Gambling, D., PALMER, C., Huffnagle, H. J., Polley, L., Muir, H., Segal, S., Lihou, C., Manvelian, G. 2005; 100 (4): 1150-1158

    Abstract

    In this multicenter, randomized, controlled study, we compared the analgesic efficacy and safety profile of a new single-dose extended-release epidural morphine (EREM) formulation (DepoDur) with that of epidural morphine sulfate for the management of postoperative pain for up to 48 h after elective cesarean delivery. ASA physical status I or II parturients (n = 75) were anesthetized with a combined spinal/epidural technique. Parturients received intrathecal bupivacaine 12-15 mg and fentanyl 10 mug for spinal anesthesia and a single epidural injection of either 5 mg of standard (conventional preservative-free) morphine or 5, 10, or 15 mg of extended-release morphine after cord clamping for postoperative pain control. Single-dose EREM 10 and 15 mg groups significantly decreased total supplemental opioid medication use and improved functional ability scores for 48 h after surgery compared with those receiving 5 mg of standard morphine. Visual analog scale pain scores at rest and with activity at 24 to 48 h after dosing were significantly better in the 10- and 15-mg single-dose EREM groups versus the standard morphine group. There were no significant differences between the two 5 mg (single-dose EREM and standard morphine) groups. Single-dose EREM was well tolerated, and most adverse events were mild to moderate in severity. Single-dose EREM is a potentially beneficial epidural analgesic for the management of post-cesarean delivery pain and has particular advantages over standard morphine for the period from 24 to 48 h after surgery.

    View details for DOI 10.1213/01.ANE.0000149544.58230.FF

    View details for Web of Science ID 000227792400040

    View details for PubMedID 15781537

  • Nitroglycerin to facilitate insertion of a labor epidural ANESTHESIOLOGY Carvalho, B. 2005; 102 (4): 872-872

    View details for Web of Science ID 000227923900036

    View details for PubMedID 15791131

  • The demise of general anesthesia in obstetrics revisited: prescription for a cure INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Lipman, S., Carvalho, B., Brock-Utne, J. 2005; 14 (1): 2-4

    View details for DOI 10.1016/j.ijoa.2004.10.003

    View details for Web of Science ID 000226572000002

    View details for PubMedID 15627530

  • Patient preferences regarding cesarean section anesthesia outcomes 36th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Carvalho, B., Macario, A., Lipman, S., Muthusamy, A. D., Fuller, A., Brummel, C., Cohen, S. E. LIPPINCOTT WILLIAMS & WILKINS. 2004: B37–B37
  • Pain tolerance in pregnancy 36th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Fuller, A. J., Lin, E., Mathusamy, A., Carvalho, B., Angst, M., Golianu, B. Y., Riley, E. T. LIPPINCOTT WILLIAMS & WILKINS. 2004: B9–B9
  • Obstetric anaesthesia workload and time of day INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Coghill, J. 2004; 13 (2): 126-128

    View details for DOI 10.1016/j.ijoa.2003.09.007

    View details for Web of Science ID 000220424500018

    View details for PubMedID 15321423

  • Neonatal chest wall rigidity following the use of remifentanil for cesarean delivery in a patient with autoimmune hepatitis and thrombocytopenia INTERNATIONAL JOURNAL OF OBSTETRIC ANESTHESIA Carvalho, B., Mirikitani, E. J., Lyell, D., Evans, D. A., Druzin, A., Riley, E. T. 2004; 13 (1): 53-56

    Abstract

    Remifentanil is a useful adjunct in general anesthesia for high-risk obstetric patients. It provides effective blunting of the rapid hemodynamic changes that may be associated with airway manipulation and surgical stimulation. There have been no previous reports of opioid-related rigidity in the neonate delivered by a parturient receiving intraoperative remifentanil. We present a case of short-lived neonatal rigidity and respiratory depression following remifentanil administration during cesarean section to a parturient with autoimmune hepatitis complicated by cirrhosis, esophageal varices and thrombocytopenia.

    View details for DOI 10.1016/j.ijoa.2003.09.001

    View details for Web of Science ID 000188228500013

    View details for PubMedID 15321443

  • Myocardial ischaemia precipitated by acute normovolaemic haemodilution TRANSFUSION MEDICINE Carvalho, B., Ridler, B. M., Thompson, J. F., Telford, R. J. 2003; 13 (3): 165-168

    Abstract

    Acute normovolaemic haemodilution (ANH) is widely used as part of a blood conservation strategy to minimize the use of allogenic blood in the peri-operative period. Its role has not been proven in a prospective randomized trial. The potential benefits must not blind clinicians to the possible hazards. We report a life-threatening complication of ANH prior to induction of anaesthesia for aortic aneurysm repair.

    View details for Web of Science ID 000183073100008

    View details for PubMedID 12791085

  • "Ultra-light" PCEA techniques in labor: Minimizing physician workload while optimizing outcome 35th Annual Meeting of the Society-for-Obstetric-Anesthesia-and-Perinatology Carvalho, B., Giarrusso, K., Durbin, M., Lipman, S., Rohlf, S., Riley, E. T., Cohen, S. E. LIPPINCOTT WILLIAMS & WILKINS. 2003: 2–2
  • Vaginal examination: a requirement before calling the anaesthetist? BRITISH JOURNAL OF ANAESTHESIA Carvalho, B., Coghill, J. 2003; 90 (3): 402-402

    View details for DOI 10.1093/bja/aeg529

    View details for Web of Science ID 000181410300039

    View details for PubMedID 12594165

  • The output of two sevoflurane vaporizers in the presence of helium BRITISH JOURNAL OF ANAESTHESIA Carvalho, B., Sanders, D. 2002; 88 (5): 711-713

    Abstract

    Modern vaporizers are designed to deliver accurate and stable concentrations of volatile anaesthetic agents. Carrier gas composition may adversely affect the output from vaporizers. No previous study has tested helium in combination with sevoflurane vaporizers, a clinically useful combination especially in anaesthesia for upper airway obstruction.This study evaluated the effect of increasing helium concentrations, carrier gas flow rates and varying the vaporizer dial setting on the output from Blease Datum and Drager Vapor 19.3 sevoflurane vaporizers.The presence of helium in the carrier gas had negligible effects on the output from both of the sevoflurane vaporizers tested. Carrier gas flow rates had the greatest effect on output but changes were within +/- 10% of baseline.Helium/oxygen mixtures can be used with these vaporizers without adversely affecting their performance.

    View details for Web of Science ID 000175399300017

    View details for PubMedID 12067011

  • Single-session hypnotherapy for smoking cessation A cost-effective alternative? European Journal of General Practice Feldman M, James U, Carvalho B, Underwood MR 2002; 8 (2): 73-74
  • Longterm functional recovery following day-case laparoscopic sterilisation: inhalational versus TIVA maintenance Ambulatory Surgery Carvalho B, Benton JI, Vickery PJ, Sneyd JR, Davies PRF, Langton JA 2002; 10 (1): 45-51
  • Viagra (R): are anaesthetists rising to the challenge? ANAESTHESIA Carvalho, B., Smith, M. 2001; 56 (1): 91-93

    View details for Web of Science ID 000166796200032

    View details for PubMedID 11167459

  • Hidden hazards of scavenging BRITISH JOURNAL OF ANAESTHESIA Hwang, N. C. 2000; 84 (6): 827-827

    View details for Web of Science ID 000087400200042

    View details for PubMedID 10895775

  • Hyperkalaemia associated with transfusion of plasma reduced blood ANAESTHESIA Horsey, P. J. 2000; 55 (3): 294-294

    View details for Web of Science ID 000085738400031

    View details for PubMedID 10744565

  • 'Near-miss' hyperkalaemic cardiac arrest associated with rapid blood transfusion ANAESTHESIA Carvalho, B., Quiney, N. F. 1999; 54 (11): 1094-1096

    Abstract

    A case is presented in which a relatively modest blood transfusion resulted in acute hyperkalaemia with a 'near-miss' cardiac arrest. While transfusion-related hyperkalaemia usually occurs in association with massive transfusions, several factors may have increased the risk of such an acute reaction. A high index of suspicion is required, especially in patients with risk factors. Anaesthetists should not be lulled into a false sense of security simply because modest volumes of blood are being transfused.

    View details for Web of Science ID 000083558400012

    View details for PubMedID 10540099

  • Hidden hazards of scavenging BRITISH JOURNAL OF ANAESTHESIA Carvalho, B. 1999; 83 (3): 532-533

    View details for Web of Science ID 000082618700067

    View details for PubMedID 10655938