- Pediatric anesthesia
- Regional analgesia
- Anesthesia for solid organ transplant
- Pediatric Difficult Airway
Clinical Professor, Anesthesiology, Perioperative and Pain Medicine
Clinical Director, Pediatric Anesthesia (2006 - 2013)
Co-Chair, Stanford University Pediatric Regional Anesthesia (SUPRA) program (2015 - Present)
Director, Pediatric Anesthesia Resource Center (2013 - 2015)
Board Certification: The Royal College of Anaesthetists, Anesthesia (1997)
Medical Education: University of Madras (1998)
Residency: Basildon General Hospital (1995) UK
Internship: Madras University Medicine (1987) India
Residency: Walsgrave Hospitals (2000) United Kingdom
FRCA, Royal College of Anaes.,UK, Anesthesiology (1997)
MD, DR MGR Medical Univ.,India, Anesthesiology (1992)
Dip NB, National Board of Examinations, Anesthesiology (1991)
MBBS, University of Madras,India, Medicine (1988)
Community and International Work
Destination Hope, San Jose Mindoro, Philippines
Opportunities for Student Involvement
HUGS, Antigua, Guatemala
Help Us Give Smiles Foundation Inc
Opportunities for Student Involvement
Radhamangalm Ramamurthi. "United States Patent 13/041,387 Indwelling Nerve Block Catheters", SRI, Stanford University, Sep 8, 2011
Current Research and Scholarly Interests
Prospective collection of pediatric regional block procedures and complications on to a national database
Multicenter Perioperative Opioid Pharmacogenetic Study
The purpose of this research study is to identify factors and genes (the DNA material that determines the makeup of the human body) that may be associated with how children respond to pain medication. Specifically, the investigators want to study factors that may be associated with pain sensitivity, morphine requirement after surgery and side-effects from morphine and other pain medications. The investigators expect that the information obtained in this research study will help us to develop more effective, safe, and tailored treatment options in the future.
Stanford is currently not accepting patients for this trial. For more information, please contact R J Ramamurthi, (650) 776 - 6297.
Anesthesia Machine Oxygen Analyzer Error Margins
LIPPINCOTT WILLIAMS & WILKINS. 2022: 53
View details for Web of Science ID 000770094900027
Ultrasound Verification of Laparoscopic-Assisted Transversus Abdominis Plane Blocks in Children Undergoing Laparoscopic Procedures.
Journal of laparoendoscopic & advanced surgical techniques. Part A
Purpose: Ultrasound-guided transversus abdominis plane (TAP) blocks have been demonstrated to decrease postoperative pain; however, laparoscopic-assisted TAP (L-TAP) blocks have not been well studied in children. Our study utilized intraoperative ultrasound to verify whether surgeon-administered blocks using only laparoscopic visualization were reliably delivered into the correct plane. Materials and Methods: Patients undergoing laparoscopic procedures were enrolled to receive L-TAP blocks. Preblock and postblock ultrasounds were performed to document the plane of local anesthetic delivery. Ultrasound images were reviewed by two blinded anesthesiologists to determine whether the L-TAP block was administered into the desired plane. Results: Fifty-one patients were enrolled. The average age was 5.9 years (range: 2 days to 17 years) and the mean weight was 25.4kg (range: 2.64-118.8kg). The most common procedures were inguinal hernia repair (n=19), appendectomy (n=10), and gastrostomy-tube placements (n=13). Nine surgeons performed 93L-TAP blocks (average: 10.3 blocks/surgeon). Ultrasound confirmed distribution in the correct plane in 53.5/93 blocks (57.5%; 58.0% for attending surgeons), with 77.4% concurrence between the anesthesiologist reviewers. Conclusion: L-TAP achieves delivery of local anesthetic into the correct tissue plane in over half the cases with minimal training. Further studies are needed to examine the effect of L-TAP blocks on reducing postoperative pain in pediatric patients.
View details for DOI 10.1089/lap.2020.0994
View details for PubMedID 34962162
Expert Consensus Statement on the Perioperative Management of Adult Patients Undergoing Head and Neck Surgery and Free Tissue Reconstruction From the Society for Head and Neck Anesthesia.
Anesthesia and analgesia
2021; 133 (1): 274-283
The perioperative care of adult patients undergoing free tissue transfer during head and neck surgical (microvascular) reconstruction is inconsistent across practitioners and institutions. The executive board of the Society for Head and Neck Anesthesia (SHANA) nominated specialized anesthesiologists and head and neck surgeons to an expert group, to develop expert consensus statements. The group conducted an extensive review of the literature to identify evidence and gaps and to prioritize quality improvement opportunities. This report of expert consensus statements aims to improve and standardize perioperative care in this setting. The Modified Delphi method was used to evaluate the degree of agreement with draft consensus statements. Additional discussion and collaboration was performed via video conference and electronic communication to refine expert opinions and to achieve consensus on key statements. Thirty-one statements were initially formulated, 14 statements met criteria for consensus, 9 were near consensus, and 8 did not reach criteria for consensus. The expert statements reaching consensus described considerations for preoperative assessment and optimization, airway management, perioperative monitoring, fluid management, blood management, tracheal extubation, and postoperative care. This group also examined the role for vasopressors, communication, and other quality improvement efforts. This report provides the priorities and perspectives of a group of clinical experts to help guide perioperative care and provides actionable guidance for and opportunities for improvement in the care of patients undergoing free tissue transfer for head and neck reconstruction. The lack of consensus for some areas likely reflects differing clinical experiences and a limited available evidence base.
View details for DOI 10.1213/ANE.0000000000005564
View details for PubMedID 34127591
Laparoscopic versus ultrasound-guided visualization of transversus abdominis plane blocks.
Journal of pediatric surgery
BACKGROUND: Ultrasound-guided (US) transversus abdominis plane (TAP) block is commonly utilized as part of a multi-modal approach for postoperative pain management. This study seeks to determine whether laparoscopic-guided TAP blocks are as effective as US-guided TAP blocks among pediatric patients.METHOD: In this prospective, randomized controlled trial, pediatric patients undergoing laparoscopic procedures were randomly assigned to one of two treatment arms: US-guided TAP block (US-arm) or laparoscopic-guided TAP block (LAP-arm). Primary outcome was PACU pain scores. Secondary outcomes included PACU opioid consumption, block completion time and block accuracy.RESULTS: Twenty-five patients were enrolled in each arm. In the LAP-arm, 59% of blocks were in the transversus abdominis plane compared to 74% of TAP blocks in the US-arm (p=0.18). Blocks were completed faster in the LAP-arm (2.1±1.9vs. 7.9±3.4min, p<0.001). The average highest PACU pain score was 3.4±3.1 for the LAP-arm and 4.3±3.8 for the US-arm (p=0.37). Overall PACU pain scores and opioid consumption were similar between the groups (1.2±1.3vs. 1.6±1.6, p=0.24; 2.2±5.8vs. 0.9±1.4MME, p=0.26).CONCLUSION: Laparoscopic TAP blocks have equivalent efficacy in post-operative pain scores, narcotic use, and tissue plane accuracy as compared to US-guided TAP blocks. They are also completed faster and may result in less operating room and general anesthetic time for the pediatric patient.
View details for DOI 10.1016/j.jpedsurg.2021.02.025
View details for PubMedID 33771368
- Tools for Assessing the Performance of Pediatric Perioperative Teams During Simulated Crises: A Psychometric Analysis of Clinician Raters' Scores SIMULATION IN HEALTHCARE-JOURNAL OF THE SOCIETY FOR SIMULATION IN HEALTHCARE 2021; 16 (1): 20–28
Variation in pediatric local anesthetic dosing for peripheral nerve blocks: an analysis from the Pediatric Regional Anesthesia Network (PRAN).
Regional anesthesia and pain medicine
BACKGROUND: Variation of local anesthetic dosing has been reported for adult peripheral nerve blocks (PNBs) and infant caudal blocks. As higher doses of local anesthetics (LA) are potentially associated with increased risk of complications (eg, local anesthetic systemic toxicity), it is important to understand the source of LA dose variation. Using the Pediatric Regional Anesthesia Network (PRAN) database, we aimed to determine if variation in dosing exists in pediatric single-injection PNBs, and what factors influence that variation.The primary aim of this study was to determine the factors associated with dosing for the 10 most commonly performed PNBs, with the secondary aim of exploring possible factors for variation such as number of blocks performed versus geographic location.METHODS: The PRAN database was used to determine the 10 most common pediatric PNBs, excluding neuraxial regional anesthetics. The 10 most common pediatric PNBs in the PRAN database were analyzed for variation of LA dose and causes for variation.RESULTS: In a cohort of 34514 children receiving PNBs, the mean age was 10.38 (+/-5.23) years, average weight was 44.88 (+/-26.66) kg and 61.8% were men. The mean bupivacaine equivalent (BE) dose was 0.86 (+/-0.5) mg kg-1 and ropivacaine was used in 65.4% of blocks. Dose decreases with age (estimate -0.016 (-0.017, -0.015; p<0.001)). In all blocks for all age groups, the range of doses that make up the central 80% of all doses exceeds the mean BE dose for the block. Variation is not related to the number blocks performed at an institution (p=0.33 (CI -0.42 to 0.15)). The dose administered for a PNB is driven in order of impact by the institution where the block was performed (Cohen's F=0.45), then by weight (0.31), type of block (0.27), LA used (0.15) and age (0.03).CONCLUSIONS: Considerable variation in dosing exists in all age groups and in all block types. The most impactful driver of local anesthetic dose is the institution where the block was performed, indicating the dosing of a potentially lethal drug is more based on local culture than on evidence.
View details for DOI 10.1136/rapm-2020-101720
View details for PubMedID 33004653
- Complications in Pediatric Regional Anesthesia An Analysis of More than 100,000 Blocks from the Pediatric Regional Anesthesia Network ANESTHESIOLOGY 2018; 129 (4): 721–32
Complications in Pediatric Regional Anesthesia: An Analysis of More than 100,000 Blocks from the Pediatric Regional Anesthesia Network.
WHAT WE ALREADY KNOW ABOUT THIS TOPIC: WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Complications in pediatric regional anesthesia are rare, so a large sample size is necessary to quantify risk. The Pediatric Regional Anesthesia Network contains data on more than 100,000 blocks administered at more than 20 children's hospitals. This study analyzed the risk of major complications associated with regional anesthesia in children.METHODS: This is a prospective, observational study of routine clinical practice. Data were collected on every regional block placed by an anesthesiologist at participating institutions and were uploaded to a secure database. The data were audited at multiple points for accuracy.RESULTS: There were no permanent neurologic deficits reported (95% CI, 0 to 0.4:10,000). The risk of transient neurologic deficit was 2.4:10,000 (95% CI, 1.6 to 3.6:10,000) and was not different between peripheral and neuraxial blocks. The risk of severe local anesthetic systemic toxicity was 0.76:10,000 (95% CI, 0.3 to 1.6:10,000); the majority of cases occurred in infants. There was one epidural abscess reported (0.76:10,000, 95% CI, 0 to 4.8:10,000). The incidence of cutaneous infections was 0.5% (53:10,000, 95% CI, 43 to 64:10,000). There were no hematomas associated with neuraxial catheters (95% CI, 0 to 3.5:10,000), but one epidural hematoma occurred with a paravertebral catheter. No additional risk was observed with placing blocks under general anesthesia. The most common adverse events were benign catheter-related failures (4%).CONCLUSIONS: The data from this study demonstrate a level of safety in pediatric regional anesthesia that is comparable to adult practice and confirms the safety of placing blocks under general anesthesia in children.
View details for PubMedID 30074928
- Early experience with PECS 1 block for Port-a-Cath insertion or removal in children at a single institution. Journal of clinical anesthesia 2018; 49: 63–64
- Bilateral continuous erector spinae plane blocks for sternotomy in a pediatric cardiac patient. Journal of clinical anesthesia 2018; 47: 82–83
PECS 1 BLOCK FOR PORT-A-CATH INSERTION OR REMOVAL IN CHILDREN: A RETROSPECTIVE REVIEW
LIPPINCOTT WILLIAMS & WILKINS. 2018: 550
View details for Web of Science ID 000460106500306
Nusinersen versus Sham Control in Later-Onset Spinal Muscular Atrophy
NEW ENGLAND JOURNAL OF MEDICINE
2018; 378 (7): 625–35
Nusinersen is an antisense oligonucleotide drug that modulates pre-messenger RNA splicing of the survival motor neuron 2 ( SMN2) gene. It has been developed for the treatment of spinal muscular atrophy (SMA).We conducted a multicenter, double-blind, sham-controlled, phase 3 trial of nusinersen in 126 children with SMA who had symptom onset after 6 months of age. The children were randomly assigned, in a 2:1 ratio, to undergo intrathecal administration of nusinersen at a dose of 12 mg (nusinersen group) or a sham procedure (control group) on days 1, 29, 85, and 274. The primary end point was the least-squares mean change from baseline in the Hammersmith Functional Motor Scale-Expanded (HFMSE) score at 15 months of treatment; HFMSE scores range from 0 to 66, with higher scores indicating better motor function. Secondary end points included the percentage of children with a clinically meaningful increase from baseline in the HFMSE score (≥3 points), an outcome that indicates improvement in at least two motor skills.In the prespecified interim analysis, there was a least-squares mean increase from baseline to month 15 in the HFMSE score in the nusinersen group (by 4.0 points) and a least-squares mean decrease in the control group (by -1.9 points), with a significant between-group difference favoring nusinersen (least-squares mean difference in change, 5.9 points; 95% confidence interval, 3.7 to 8.1; P<0.001). This result prompted early termination of the trial. Results of the final analysis were consistent with results of the interim analysis. In the final analysis, 57% of the children in the nusinersen group as compared with 26% in the control group had an increase from baseline to month 15 in the HFMSE score of at least 3 points (P<0.001), and the overall incidence of adverse events was similar in the nusinersen group and the control group (93% and 100%, respectively).Among children with later-onset SMA, those who received nusinersen had significant and clinically meaningful improvement in motor function as compared with those in the control group. (Funded by Biogen and Ionis Pharmaceuticals; CHERISH ClinicalTrials.gov number, NCT02292537 .).
View details for PubMedID 29443664
Nusinersen versus Sham Control in Infantile-Onset Spinal Muscular Atrophy.
The New England journal of medicine
2017; 377 (18): 1723–32
Spinal muscular atrophy is an autosomal recessive neuromuscular disorder that is caused by an insufficient level of survival motor neuron (SMN) protein. Nusinersen is an antisense oligonucleotide drug that modifies pre-messenger RNA splicing of the SMN2 gene and thus promotes increased production of full-length SMN protein.We conducted a randomized, double-blind, sham-controlled, phase 3 efficacy and safety trial of nusinersen in infants with spinal muscular atrophy. The primary end points were a motor-milestone response (defined according to results on the Hammersmith Infant Neurological Examination) and event-free survival (time to death or the use of permanent assisted ventilation). Secondary end points included overall survival and subgroup analyses of event-free survival according to disease duration at screening. Only the first primary end point was tested in a prespecified interim analysis. To control the overall type I error rate at 0.05, a hierarchical testing strategy was used for the second primary end point and the secondary end points in the final analysis.In the interim analysis, a significantly higher percentage of infants in the nusinersen group than in the control group had a motor-milestone response (21 of 51 infants [41%] vs. 0 of 27 [0%], P<0.001), and this result prompted early termination of the trial. In the final analysis, a significantly higher percentage of infants in the nusinersen group than in the control group had a motor-milestone response (37 of 73 infants [51%] vs. 0 of 37 [0%]), and the likelihood of event-free survival was higher in the nusinersen group than in the control group (hazard ratio for death or the use of permanent assisted ventilation, 0.53; P=0.005). The likelihood of overall survival was higher in the nusinersen group than in the control group (hazard ratio for death, 0.37; P=0.004), and infants with a shorter disease duration at screening were more likely than those with a longer disease duration to benefit from nusinersen. The incidence and severity of adverse events were similar in the two groups.Among infants with spinal muscular atrophy, those who received nusinersen were more likely to be alive and have improvements in motor function than those in the control group. Early treatment may be necessary to maximize the benefit of the drug. (Funded by Biogen and Ionis Pharmaceuticals; ENDEAR ClinicalTrials.gov number, NCT02193074 .).
View details for DOI 10.1056/NEJMoa1702752
View details for PubMedID 29091570
The Role of Sugammadex in Symptomatic Transient Neonatal Myasthenia Gravis: A Case Report.
A & A case reports
2017; 9 (9): 271–73
We describe the case of a 3-week-old boy with pyloric stenosis who presented for laparoscopic pyloromyotomy in the setting of symptomatic transient neonatal myasthenia gravis. The patient received muscle relaxation with rocuronium, and neuromuscular blockade was successfully reversed with sugammadex with recovery guided by train-of-four monitoring. He was extubated uneventfully without complications. Because sugammadex binds directly to rocuronium rather than interfering with acetylcholine metabolism, it might provide a good option for reversal of neuromuscular blockade in transient neonatal myasthenia gravis.
View details for PubMedID 28691986
Improving prediction of surgery duration using operational and temporal factors.
AMIA ... Annual Symposium proceedings / AMIA Symposium. AMIA Symposium
2012; 2012: 456-462
Inherent uncertainties in surgery durations impact many critical metrics about the performance of an operating room (OR) environment. OR schedules that are robust to natural variability in surgery durations require surgery duration estimates that are unbiased, with high accuracy, and with few cases with large absolute errors. Earlier studies have shown that factors such as patient severity, personnel, and procedure type greatly affect the accuracy of such estimations. In this paper we investigate whether operational and temporal factors can be used to improve these estimates further. We present an adjustment method based on a combination of these operational and temporal factors. We validate our method with two years of detailed operational data from an electronic medical record. We conclude that while improving estimates of surgery durations is possible, the inherent variability in such estimates remains high, necessitating caution in their use when optimizing OR schedules.
View details for PubMedID 23304316
View details for PubMedCentralID PMC3540440
- Improving electrical safety for patients with Epidermolysis bullosa PEDIATRIC ANESTHESIA 2008; 18 (11): 1107-1109
The use of dexmedetomidine during laryngoscopy, bronchoscopy, and tracheal extubation following tracheal reconstruction
2007; 17 (12): 1212-1214
We report the use of dexmedetomidine for laryngoscopy, rigid bronchoscopy, and tracheal extubation in the operating room in two children who had undergone tracheal reconstruction 1 week previously. Dexmedetomidine in combination with propofol provided appropriately deep anesthesia during these brief but stimulating procedures without cardiovascular or respiratory depression.
View details for DOI 10.1111/j.1460-9592.2007.02346.x
View details for PubMedID 17986042
- Local anesthetic pharmacology in pediatric anesthesia Techniques in Regional Anesthesia and Pain Management 2007; 11 (4): 229-234
Clonidine for the prevention of emergence agitation in young children: efficacy and recovery profile
2006; 16 (5): 554-559
Emergence agitation (EA) is a common postoperative problem in young children who have received sevoflurane and isoflurane for general anesthesia. This randomized, double-blinded study evaluated the efficacy of intraoperative clonidine in reducing EA, and describes its recovery profile.With Institutional Review Board approval and informed consent, children undergoing brief, minimally painful procedures were studied. All children received preemptive analgesia with acetaminophen and ketorolac, sevoflurane for induction, and isoflurane for maintenance of anesthesia. Children received either 2 microg.kg(-1) clonidine or placebo intravenously (i.v.) following induction of anesthesia. Children were observed postoperatively for behavior and side effects, and their parents were telephoned the next day to determine postdischarge recovery characteristics.One hundred and twenty children were included in this study: 59 of whom received clonidine, and 61 placebo; 41% of those in the placebo group exhibited moderate-severe EA compared with only 22% of those in the clonidine group (P < 0.03). Compared with those who received placebo, children who received clonidine awakened more slowly (22 min vs 14 min), had a longer postanesthesia care unit stay (57 min vs 46 min), and experienced sleepiness more frequently after discharge (75% vs 39%; all comparisons significant at P < 0.03). There were no adverse cardiorespiratory events in either group.Findings demonstrate that i.v. clonidine administered after induction of anesthesia significantly reduces the incidence of EA in young children, but is associated with sleepiness postoperatively.
View details for DOI 10.1111/j.1460-9592.2006.01818
View details for Web of Science ID 000236769600009
View details for PubMedID 16677266
- Acute gastric distension: a lesson from the classics HOSPITAL MEDICINE 2001; 62 (3): 187-187
- Anaesthesia for Intestinal Obstruction in children http://www.anaesthesiauk.com/article.aspx?articleid=101005