Sherry M. Wren, MD, FACS, FCS(ECSA), FISS

All Publications

• Variations in Current Practice and Protocols of Intraoperative Multimodal Analgesia: A Cross-Sectional Study Within a Six-Hospital US Health Care System. Anesthesia and analgesia Graham, L. A., Illarmo, S. S., Wren, S. M., Odden, M. C., Mudumbai, S. C. 2024

  Abstract

  Multimodal analgesia (MMA) aims to reduce surgery-related opioid needs by adding nonopioid pain medications in postoperative pain management. In light of the opioid epidemic, MMA use has increased rapidly over the past decade. We hypothesize that the rapid adoption of MMA has resulted in variation in practice. This cross-sectional study aimed to determine how MMA practices have changed over the past 6 years and whether there is variation in use by patient, provider, and facility characteristics.Our study population includes all patients undergoing surgery with general anesthesia at 1 of 6 geographically similar hospitals in the United States between January 1, 2017 and December 31, 2022. Intraoperative pain medications were obtained from the hospital's perioperative information management system. MMA was defined as an opioid plus at least 2 other nonopioid analgesics. Frequencies, χ2 tests (χ2), range, and interquartile range (IQR) were used to describe variation in MMA practice over time, by patient and procedure characteristics, across hospitals, and across anesthesiologists. Multivariable logistic regression was conducted to understand the independent contributions of patient and procedural factors to MMA use.We identified 25,386 procedures among 21,227 patients. Overall, 46.9% of cases met our definition of MMA. Patients who received MMA were more likely to be younger females with a lower comorbidity burden undergoing longer and more complex procedures that included an inpatient admission. MMA use has increased steadily by an average of 3.0% each year since 2017 (95% confidence interval =2.6%-3.3%). There was significant variation in use across hospitals (n = 6, range =25.9%-68.6%, χ2 = 3774.9, P < .001) and anesthesiologists (n = 190, IQR =29.8%-65.8%, χ2 = 1938.5, P < .001), as well as by procedure characteristics. The most common MMA protocols contained acetaminophen plus regional anesthesia (13.0% of protocols) or acetaminophen plus dexamethasone (12.2% of protocols). During the study period, the use of opioids during the preoperative or intraoperative period decreased from 91.4% to 86.0% of cases; acetaminophen use increased (41.9%-70.5%, P < .001); dexamethasone use increased (24.0%-36.1%, P < .001) and nonsteroidal anti-inflammatory drugs (NSAIDs) increased (6.9%-17.3%, P < .001). Gabapentinoids and IV lidocaine were less frequently used but also increased (0.8%-1.6% and 3.4%-5.3%, respectively, P < .001).In a large integrated US health care system, approximately 50% of noncardiac surgery patients received MMA. Still, there was wide variation in MMA use by patient and procedure characteristics and across hospitals and anesthesiologists. Our findings highlight a need for further research to understand the reasons for these variations and guide the safe and effective adoption of MMA into routine practice.

  View details for DOI 10.1213/ANE.0000000000007299

  View details for PubMedID 39453849

• Patient-Centered Outcomes and Preoperative Discussions. JAMA surgery Rajasingh, C. M., Wren, S. M. 2024

  View details for DOI 10.1001/jamasurg.2024.4699

  View details for PubMedID 39441607

• Haptic Guidance and Haptic Error Amplification in a Virtual Surgical Robotic Training Environment. IEEE transactions on haptics Oquendo, Y. A., Coad, M. M., Wren, S. M., Lendvay, T. S., Nisky, I., Jarc, A. M., Okamura, A. M., Chua, Z. 2024; 17 (3): 417-428

  Abstract

  Teleoperated robotic systems have introduced more intuitive control for minimally invasive surgery, but the optimal method for training remains unknown. Recent motor learning studies have demonstrated that exaggeration of errors helps trainees learn to perform tasks with greater speed and accuracy. We hypothesized that training in a force field that pushes the user away from a desired path would improve their performance on a virtual reality ring-on-wire task. Thirty-eight surgical novices trained under a no-force, guidance, or error-amplifying force field over five days. Completion time, translational and rotational path error, and combined error-time were evaluated under no force field on the final day. The groups significantly differed in combined error-time, with the guidance group performing the worst. Error-amplifying field participants did not plateau in their performance during training, suggesting that learning was still ongoing. Guidance field participants had the worst performance on the final day, confirming the guidance hypothesis. Observed trends also suggested that participants who had high initial path error benefited more from guidance. Error-amplifying and error-reducing haptic training for robot-assisted telesurgery benefits trainees of different abilities differently, with our results indicating that participants with high initial combined error-time benefited more from guidance and error-amplifying force field training.

  View details for DOI 10.1109/TOH.2024.3350128

  View details for PubMedID 38194379

• AI Imaging Analysis Needs Evaluation Before Implementation. JAMA surgery Seib, C. D., Wren, S. M. 2024

  View details for DOI 10.1001/jamasurg.2024.0629

  View details for PubMedID 38598188

• Use of natural language processing method to identify regional anesthesia from clinical notes. Regional anesthesia and pain medicine Graham, L. A., Illarmo, S. S., Wren, S. M., Odden, M. C., Mudumbai, S. C. 2024

  Abstract

  INTRODUCTION: Accurate data capture is integral for research and quality improvement efforts. Unfortunately, limited guidance for defining and documenting regional anesthesia has resulted in wide variation in documentation practices, even within individual hospitals, which can lead to missing and inaccurate data. This cross-sectional study sought to evaluate the performance of a natural language processing (NLP)-based algorithm developed to identify regional anesthesia within unstructured clinical notes.METHODS: We obtained postoperative clinical notes for all patients undergoing elective non-cardiac surgery with general anesthesia at one of six Veterans Health Administration hospitals in California between January 1, 2017, and December 31, 2022. After developing and executing our algorithm, we compared our results to a frequently used referent, the Corporate Data Warehouse structured data, to assess the completeness and accuracy of the currently available data. Measures of agreement included sensitivity, positive predictive value, false negative rate, and accuracy.RESULTS: We identified 27,713 procedures, of which 9310 (33.6%) received regional anesthesia. 96.6% of all referent regional anesthesia cases were identified in the clinic notes with a very low false negative rate and good accuracy (false negative rate=0.8%, accuracy=82.5%). Surprisingly, the clinic notes documented more than two times the number of regional anesthesia cases that were documented in the referent (algorithm n=9154vs referent n=4606).DISCUSSION: While our algorithm identified nearly all regional anesthesia cases from the referent, it also identified more than two times as many regional anesthesia cases as the referent, raising concerns about the accuracy and completeness of regional anesthesia documentation in administrative and clinical databases. We found that NLP was a promising alternative for identifying clinical information when existing databases lack complete documentation.

  View details for DOI 10.1136/rapm-2024-105340

  View details for PubMedID 38580338

• Editorial commentary and call for papers-Humanitarian surgery in conflict zones. World journal of surgery Hardcastle, T. C., Gyedu, A., Doherty, G. M., Wren, S. M. 2024

  View details for DOI 10.1002/wjs.12119

  View details for PubMedID 38407321

• Socioeconomic Status and Postoperative Emergency Department Visits-Reply. JAMA surgery Rajasingh, C. M., Wren, S. M. 2024

  View details for DOI 10.1001/jamasurg.2023.8010

  View details for PubMedID 38381441

• Mapping the Discharge Process After Surgery. JAMA surgery Graham, L. A., Illarmo, S., Gray, C. P., Harris, A. H., Wagner, T. H., Hawn, M. T., Iannuzzi, J. C., Wren, S. M. 2024

  Abstract

  Care transition models are structured approaches used to ensure the smooth transfer of patients between health care settings or levels of care, but none currently are tailored to the surgical patient. Tailoring care transition models to the unique needs of surgical patients may lead to significant improvements in surgical outcomes and reduced care fragmentation. The first step to developing surgical care transition models is to understand the surgical discharge process.To map the surgical discharge process in a sample of US hospitals and identify key components and potential challenges specific to a patient's discharge after surgery.This qualitative study followed a cognitive task analysis framework conducted between January 1, 2022, and April 1, 2023, in Veterans Health Administration (VHA) hospitals. Observations (n = 16) of discharge from inpatient care after a surgical procedure were conducted in 2 separate VHA surgical units. Interviews (n = 13) were conducted among VHA health care professionals nationwide.Postoperative hospital discharge.Data were coded according to the principles of thematic analysis, and a swim lane process map was developed to represent the study findings.At the hospitals in this study, the discharge process observed for a surgical patient involved multidisciplinary coordination across the surgery team, nursing team, case managers, dieticians, social services, occupational and physical therapy, and pharmacy. Important components for a surgical discharge that were not incorporated in the current care transition models included wound care education and supplies; pain control; approvals for nonhome postdischarge locations; and follow-up plans for wounds, ostomies, tubes, and drains at discharge. Potential challenges to the surgical discharge process included social situations (eg, home environment and caregiver availability), team communication issues, and postdischarge care coordination.These findings suggest that current and ongoing studies of discharge care transitions for a patient after surgery should consider pain control; wounds, ostomies, tubes, and drains; and the impact of challenging social situations and interdisciplinary team coordination on discharge success.

  View details for DOI 10.1001/jamasurg.2023.7539

  View details for PubMedID 38381415

• Defining humanitarian surgery: international consensus in global surgery. The British journal of surgery McKnight, G., Friebel, R., Marks, I., Almaqadma, A., Youssef Seleem, M., Tientcheu, T. F., Saleh, R., Ryan-Coker, M., Emodi, R., Seida, M., Barden, J., Redmond, A., Amirtharajah, M., Wren, S. M., Leather, A., Hargest, R. 2024; 111 (2)

  View details for DOI 10.1093/bjs/znae024

  View details for PubMedID 38372664

  View details for PubMedCentralID PMC10875721

• A retrospective study of laparoscopic, robotic-assisted, and open emergent/urgent cholecystectomy based on the PINC AI Healthcare Database 2017-2020. World journal of emergency surgery : WJES Campbell, S., Lee, S. H., Liu, Y., Wren, S. M. 2023; 18 (1): 55

  Abstract

  Robotic-assisted cholecystectomy (RAC) is becoming increasingly common, but the outcomes of emergent/urgent robotic-assisted cholecystectomies compared to emergent laparoscopic (LC) and open cholecystectomies (OC) remain understudied.The PINC AI Healthcare Database was queried to identify adults who underwent emergent or urgent (Em-Ur) cholecystectomy between January 1, 2017, and December 31, 2020. Immediate postoperative and 30-day outcomes were identified including intraoperative complications, transfusion, conversion, postoperative complication, and hospital length of stay. Propensity score matching was done to compare outcomes between Em-Ur robotic-assisted, laparoscopic, and open cholecystectomies Subgroup analyses were performed comparing RAC done with and without fluorescent imaging as well as comparing RAC and LC performed for patients with class 3 obesity (BMI ≥ 40 kg/m2).RAC Em-Ur cholecystectomies are being performed with increasing frequency and is the most utilized modality for patients with class 3 obesity. There was no difference in intraoperative complications (0.3%), bile duct injury (0.2%), or postoperative outcomes between RAC and LC. LC had significantly shorter operating room times (96 min (75,128)) compared to RAC (120 min (90,150)). There was a significant lower rate of conversion to open in RAC (1.9%) relative to LC (3.2%) in both the overall population and the class 3 obesity sub-analysis (RAC-2.6% vs. LC-4.4%). There was no difference in outcomes in robotic-assisted cholecystectomies done with and without fluorescent imaging.A comparison of propensity score-matched cohorts of emergent/urgent robotic-assisted and laparoscopic cholecystectomy indicates that robotic-assisted cholecystectomy is a safe alternative to laparoscopic cholecystectomy, and that both have superior outcomes to open cholecystectomies.

  View details for DOI 10.1186/s13017-023-00521-8

  View details for PubMedID 38037087

  View details for PubMedCentralID 8067374

• Emergency Department Visit Rates After Ambulatory Surgery. JAMA surgery Rajasingh, C. M., Wren, S. M. 2023

  View details for DOI 10.1001/jamasurg.2023.4788

  View details for PubMedID 37910124

• Demographic Representation in Clinical Trials Sponsored by the United States Department of Veterans Affairs. International journal of radiation oncology, biology, physics Gomez, G. T., Turner, B. E., Steinberg, J. R., Wren, S. 2023; 117 (2S): e20

  Abstract

  Non-White racial and ethnic groups remain underrepresented in oncology clinical trials within the United States and face ongoing barriers to participation. Previous reports cite positive attitudes toward clinical trials (CTs) among veterans, with altruism and a strong sense of community posited as driving forces for participation. Our objective was to characterize demographic representation among CTs sponsored by the U.S. Department of Veterans Affairs (VA) and U.S. Department of Defense (DoD) compared to trials with no VA/DoD sponsorship.We incorporated data from U.S. CTs registered in ClinicalTrials.gov between March 2000 and March 2020 using the Aggregate Analysis of ClinicalTrials.gov database, and stratified CTs by sponsorship into the following groups: (1) VA, (2) DoD or (3) non-VA/DoD sponsorship. We extracted CT enrollment data for gender and four race/ethnicity categories: White, Hispanic/Latinx, Black, and Asian. After calculating gender and race-specific proportions for each CT, we compared the median proportion of White, non-White, Black, Asian, and Hispanic participants between (a) VA and non-VA/DoD CTs, (b) DoD and non-VA/DoD CTs, and (c) VA CTs and the Veterans Health Agency (VHA) patient population using Wilcoxon signed rank tests.This study included 13942 CTs; of these, 490 (94%) VA, 38 (95%) DoD, and 12574 (95%) non-VA/DoD sponsored CTs reported race/ethnicity data. Non-VA/DoD entities sponsored a greater relative number of oncology CTs (29%) than did the VA (5%) or DoD (3%). Characterization of CTs by participant race/ethnicity demonstrated median non-White enrollment was 68% greater in VA CTs (p<0.001) and 34% greater in DoD CTs (p = 0.138) than non-VA/DoD CTs. Increased non-White VA CT enrollment was driven largely by the higher median proportion of Black participants (24%)-more than double that of non-VA/DoD CTs (10%) (Table 1). Comparison between the median proportion of Black participants in VA CTs and VHA patient demographics (15.8% Black) revealed that VA CTs enroll a greater percentage of Black participants than reflected in the VHA patient population (p<0.001).This characterization of veteran involvement in CTs demonstrates that VA sponsored CTs feature significantly greater representation of minorities, a pattern driven exclusively by greater enrollment of black patients. This work prompts further exploration into modeling VA enrollment strategies in non-VA CTs and increasing VA sponsorship of cancer trials to stimulate inclusion of underrepresented populations in oncology CTs.

  View details for DOI 10.1016/j.ijrobp.2023.06.691

  View details for PubMedID 37784849

• Freestanding Ambulatory Surgery Centers and Patients Undergoing Outpatient Knee Arthroplasty. JAMA network open Rajasingh, C. M., Baker, L. C., Wren, S. M. 2023; 6 (8): e2328343

  Abstract

  Importance: In 2018, Medicare removed total knee arthroplasty from the list of inpatient-only procedures, resulting in a new pool of patients eligible for outpatient total knee arthroplasty. How this change was associated with the characteristics of patients undergoing outpatient knee arthroplasty at hospital-owned surgery centers (HOSCs) vs freestanding ambulatory surgery centers (FASCs) is unknown.Objectives: To describe the characteristics of patients undergoing outpatient, elective total and partial knee arthroplasty in 2017 and 2018 and to compare the cohorts receiving treatment at FASCs and HOSCs.Design, Setting, and Participants: This observational retrospective cohort study included 5657 patients having elective, outpatient partial and total knee arthroplasty in the Florida and Wisconsin State Ambulatory Surgery Databases in 2017 and 2018. Prior admissions were identified in the State Inpatient Database. Statistical analysis was performed from March to June 2022.Main Outcomes and Measures: Characteristics of patients undergoing surgery at a FASC vs a HOSC in 2017 and 2018 were compared.Results: A total of 5657 patients (mean [SD] age, 64.2 [9.9] years; 2907 women [51.4%]) were included in the study. Outpatient knee arthroplasties increased from 1910 in 2017 to 3747 in 2018 and were associated with an increase in total knee arthroplasties (474 in 2017 vs 2065 in 2018). The influx of patients undergoing outpatient knee arthroplasty was associated with an amplification of differences between the patients treated at FASCs and the patients treated at HOSCs. Patients with private payer insurance seen at FASCs increased from 63.4% in 2017 (550 of 867) to 72.7% in 2018 (1272 of 1749) (P<.001), while the percentage of patients with private payer insurance seen at HOSCs increased, but to a lesser extent (41.6% [427 of 1027] in 2017 vs 46.4% [625 of 1346] in 2018; P<.001). In 2017, the percentages of White patients seen at FASCs and HOSCs were similar (85.0% [737 of 867] vs 88.2% [906 of 1027], respectively); in 2018, the percentage of White patients seen at FASCs had increased and was significantly different from the percentage of White patients seen at HOSCs (90.6% [1585 of 1749] vs 87.9% [1183 of 1346]; P=.01). Both types of facilities saw an increase from 2017 to 2018 in the percentage of patients from communities of low social vulnerability, but this increase was greater for FASCs (FASCs: 6.7% [58 of 867] in 2017 vs 33.9% [593 of 1749] in 2018; HOSCs: 7.6% [78 of 1027] in 2017 vs 21.2% [285 of 1346] in 2018). Finally, while FASCs and HOSCs had cared for a similar portion of patients with prior admissions in 2017 (7.8% [68 of 867] vs 9.4% [97 of 1027], respectively; P=.25), in 2018, FASCs cared for fewer patients with prior admissions than HOSCs (4.0% [70 of 1749] vs 8.1% [109 of 1346]; P<.001).Conclusions: This study suggests that the increase in the number of patients undergoing outpatient knee arthroplasty in 2018 corresponded to FASCs treating a greater share of patients who were White, covered by private payer insurance, and healthier. These findings raise a concern that as more operations transition to the outpatient setting, variability in access to FASCs may increase, leaving hospital-owned centers to bear a greater share of the burden of caring for more vulnerable patients with more severe illness.

  View details for DOI 10.1001/jamanetworkopen.2023.28343

  View details for PubMedID 37561458

• Correlation of Performance on ENTRUST and Traditional Oral Objective Structured Clinical Examination for High-Stakes Assessment in the College of Surgeons of East, Central, and Southern Africa. Journal of the American College of Surgeons Liebert, C. A., Melcer, E. F., Eddington, H., Trickey, A., Shields, S., Lee, M., Korndorffer, J. R., Bekele, A., Wren, S. M., Lin, D. T. 2023

  Abstract

  To address the global need for accessible evidence-based tools for competency-based education, we developed ENTRUST, an innovative online virtual patient simulation platform to author and securely deploy case scenarios to assess surgical decision-making competence.In partnership with COSECSA, ENTRUST was piloted during the Membership of the College of Surgeons (MCS) 2021 examination. Examinees (n=110) completed the traditional 11-station oral OSCE, followed by three ENTRUST cases, authored to query similar clinical content of three corresponding OSCE cases. ENTRUST scores were analyzed for associations with MCS Exam outcome using independent sample t-tests. Correlation of ENTRUST scores to MCS Exam Percentage and OSCE Station Scores were calculated with Pearson correlations. Bivariate and multivariate analyses were performed to evaluate predictors of performance.ENTRUST performance was significantly higher in examinees who passed the MCS Exam compared to those who failed (p<0.001). ENTRUST score was positively correlated with MCS Exam Percentage (p<0.001) and combined OSCE Station Scores (p<0.001). On multivariate analysis, there was a strong association between MCS Exam Percentage and ENTRUST Grand Total Score (p<0.001), Simulation Total Score (p=0.018), and Question Total Score (p<0.001). Age was a negative predictor for ENTRUST Grand Total and Simulation Total Score, but not for Question Total Score. Sex, native language status, and intended specialty were not associated with performance on ENTRUST.This study demonstrates feasibility and initial validity evidence for the use of ENTRUST in a high-stakes examination context for assessment of surgical decision-making. ENTRUST holds potential as an accessible learning and assessment platform for surgical trainees worldwide.

  View details for DOI 10.1097/XCS.0000000000000740

  View details for PubMedID 37144790

• High-Quality Data Collection in Low-Resource Settings: An Imperative to Improving Global Surgical Care. World journal of surgery Wild, H., Wren, S. M. 2023

  View details for DOI 10.1007/s00268-023-06986-7

  View details for PubMedID 36995398

• Robotic General Surgery Trends in the Veterans Health Administration, Community Practice, and Academic Centers From 2013 to 2021. JAMA surgery Mills, J., Liebert, C., Wren, S. M., Pratt, J. S., Earley, M., Eisenberg, D. 2023

  Abstract

  This cross-sectional study compares trends in use of robotic surgery for general surgical procedures among the Veterans Health Administration (VHA), community practice, and academic health centers from 2013 to 2021.

  View details for DOI 10.1001/jamasurg.2022.7728

  View details for PubMedID 36790771

• Characterizing Moral Injury and Distress in US Military Surgeons Deployed to Far-Forward Combat Environments in Afghanistan and Iraq. JAMA network open Ryu, M. Y., Martin, M. J., Jin, A. H., Tabor, H. K., Wren, S. M. 2023; 6 (2): e230484

  Abstract

  Importance: Moral injury and distress (MID), which occurs when individuals have significant dissonance with their belief system and overwhelming feelings of being powerless to do what is believed to be right, has not been explored in the unique population of military surgeons deployed far forward in active combat settings. Deployed military surgeons provide care to both injured soldiers and civilians under command-driven medical rules of engagement (MROE) in variably resourced settings. This practice setting has no civilian corollary for comparison or current specific tool for measurement.Objective: To characterize MID among military surgeons deployed during periods of high casualty volumes through a mixed-methods approach.Design, Setting, and Participants: This qualitative study using convergent mixed methods was performed from May 2020 to October 2020. Participants included US military surgeons who had combat deployments to a far-forward role 2 treatment facility during predefined peak casualty periods in Iraq (2003-2008) and Afghanistan (2009-2012), as identified by purposeful snowball sampling. Data analysis was performed from October 2020 to May 2021.Main Outcomes and Measures: Measure of Moral Distress for Healthcare Professionals (MMD-HP) survey and individual, semistructured interviews were conducted to thematic saturation.Results: The total cohort included 20 surgeons (mean [SD] age, 38.1 [5.2] years); 16 (80%) were male, and 16 (80%) had 0 or 1 prior deployment. Deployment locations were Afghanistan (11 surgeons [55%]), Iraq (9 surgeons [45%]), or both locations (3 surgeons [15%]). The mean (SD) MMD-HP score for the surgeons was 104.1 (39.3). The primary thematic domains for MID were distressing outcomes (DO) and MROE. The major subdomains of DO were guilt related to witnessing horrific injuries; treating pregnant women, children, and US soldiers; and second-guessing decisions. The major subdomains for MROE were forced transfer of civilian patients, limited capabilities and resources, inexperience in specialty surgical procedures, and communication with command. Postdeployment manifestations of MID were common and affected sleep, medical practice, and interpersonal relationships.Conclusions and Relevance: In this qualitative study, MID was ubiquitous in deployed military surgeons. Thematic observations about MID, specifically concerning the domains of DO and MROE, may represent targets for further study to develop an evaluation tool of MID in this population and inform possible programs for identification and mitigation of MID.

  View details for DOI 10.1001/jamanetworkopen.2023.0484

  View details for PubMedID 36821112

• Global Surgery: The Road Less Traveled and How to Get Back on Track. World journal of surgery Ewbank, C., Derbew, M., Ratnayake, A., Gupta, S., Hughes, M. C., Wren, S. M., Kushner, A. L. 2023

  View details for DOI 10.1007/s00268-023-06920-x

  View details for PubMedID 36709216

• Perioperative Risk Assessment in Humanitarian Settings: A Scoping Review. World journal of surgery Wild, H., Stewart, B. T., LeBoa, C., Jewell, T., Mehta, K., Wren, S. M. 2023

  Abstract

  No validated perioperative risk assessment models currently exist for use in humanitarian settings. To inform the development of a perioperative mortality risk assessment model applicable to humanitarian settings, we conducted a scoping review of the literature to identify reports that described perioperative risk assessment in surgical care in humanitarian settings and LMICs.We conducted a scoping review of the literature to identify records that described perioperative risk assessment in low-resource or humanitarian settings. Searches were conducted in databases including: PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature, Web of Science, World Health Organization Catalog, and Google Scholar.Our search identified 1582 records. After title/abstract and full text screening, 50 reports remained eligible for analysis in quantitative and qualitative synthesis. These reports presented data from over 37 countries from public, NGO, and military facilities. Data reporting was highly inconsistent: fewer than half of reports presented the indication for surgery; less than 25% of reports presented data on injury severity or prehospital data. Most elements of perioperative risk models designed for high-resource settings (e.g., vital signs, laboratory data, and medical comorbidities) were unavailable.At present, no perioperative mortality risk assessment model exists for use in humanitarian settings. Limitations in consistency and quality of data reporting are a primary barrier, however, can be addressed through data-driven identification of several key variables encompassed by a minimum dataset. The development of such a score is a critical step toward improving the quality of care provided to populations affected by conflict and protracted humanitarian crises.

  View details for DOI 10.1007/s00268-023-06893-x

  View details for PubMedID 36631590

• Applying Cognitive Task Analysis to Health Services Research. Health services research Graham, L. A., Gray, C., Wagner, T. H., Illarmo, S., Hawn, M. T., Wren, S. M., Iannuzzi, J., Harris, A. H. 2022

  Abstract

  OBJECTIVE: Designing practical decision support tools and other healthcare technology in health services research relies on a clear understanding of the cognitive processes that underlie the use of these tools. Unfortunately, methods to explore cognitive processes are rarely used in health services research. Thus, the objective of this manuscript is to introduce cognitive task analysis (CTA), a family of methods to study cognitive processes involved in completing a task, to a health services research audience. This methods article describes CTA procedures, proposes a framework for their use in health services research studies, and provides an example of its application in a pilot study.DATA SOURCES AND STUDY SETTING: Observations and interviews of healthcare providers involved in discharge planning at 6 hospitals in the Veterans Health Administration.STUDY DESIGN: Qualitative study of discharge planning using CTA.DATA COLLECTION / EXTRACTION METHODS: Data were collected from structured observations and semi-structured interviews using the Critical Decision Method and analyzed using thematic analysis.PRINCIPAL FINDINGS: We developed an adaptation of CTA that could be used in a clinical environment to describe clinical decision-making and other cognitive processes. The adapted CTA framework guides the user through four steps: 1) Planning, 2) Environmental Analysis, 3) Knowledge Elicitation, and 4) Analyses and Results. This adapted CTA framework provides an iterative and systematic approach to identifying and describing the knowledge, expertise, thought processes, procedures, actors, goals, and mental strategies that underlie completing a clinical task.CONCLUSIONS: A better understanding of the cognitive processes that underly clinical tasks is key to developing healthcare technology and decision-support tools that will have a meaningful impact on processes of care and patient outcomes. Our adapted framework offers a more rigorous and detailed method for identifying task-related cognitive processes in implementation studies and quality improvement. Our adaptation of this underutilized qualitative research method may be helpful to other researchers and inform future research in health services research. This article is protected by copyright. All rights reserved.

  View details for DOI 10.1111/1475-6773.14106

  View details for PubMedID 36421922

• Defining Essential Surgery in the US During the COVID-19 Pandemic Response. JAMA surgery Mattingly, A. S., Eddington, H. S., Rose, L., Morris, A. M., Trickey, A. W., Cullen, M. R., Wren, S. M. 2022

  Abstract

  This cohort study compares the volume of performed surgical procedures classified as essential, urgent, and nonurgent before and after elective surgeries were restricted during the COVID-19 pandemic in the US.

  View details for DOI 10.1001/jamasurg.2022.3944

  View details for PubMedID 36260330

• Armed Conflicts Destroy Civilian Health Systems: Cancer Screening in Ukraine the Newest Casualty of World Conflict. World journal of surgery Wren, S. M., Wild, H. 2022

  View details for DOI 10.1007/s00268-022-06700-z

  View details for PubMedID 35948827

• Characterization of Humanitarian Trauma Care by US Military Facilities During Combat Operations in Afghanistan and Iraq. Annals of surgery Gurney, J. M., Graf, V., Staudt, A. M., Trevino, J. D., VanFosson, C. A., Wild, H., Wren, S. M. 2022

  Abstract

  OBJECTIVE: To characterize humanitarian trauma care delivered by US military treatment facilities (MTFs) in Afghanistan and Iraq during combat operations.BACKGROUND: International Humanitarian Law, which includes the Geneva Conventions, defines protections and standards of treatment to victims of armed conflicts. In 1949 these standards expanded to include injured civilians. In 2001, the Global War on Terror began in Afghanistan and expanded to Iraq in 2003. US MTFs provided care to all military forces, civilians, and enemy prisoners. A thorough understanding of the scope, epidemiology, resource requirements and outcomes of civilian trauma in combat zones has not been previously characterized.METHODS: Retrospective cohort analysis of the Department of Defense Trauma Registry from 2005-2019. Inclusion criteria were civilians and non-NATO coalition personnel (NNCP) with traumatic injuries treated at MTFs in Afghanistan and Iraq. Patient demographics, mechanism of injury, resource requirements, procedures, and outcomes were categorized.RESULTS: A total of 29,963 casualties were eligible from the Registry. There were 16,749 (55.9%) civilians and 13,214 (44.1%) NNCP. The majority of patients were age >13 years [26,853 (89.6%)] and male [28,000 (93.4%)]. Most injuries were battle-related: 12,740 (76.1%) civilians and 11,099 (84.0%) NNCP. Penetrating trauma was the most common cause of both battle and nonbattle injuries: 12,293 (73.4%) civilian and 10,029 (75.9%) NNCP. Median injury severity score (ISS) was 9 in each cohort with ISS scores ≥ 25 in 2,236 (13.4%) civilians and 1,398 (10.6%) NNCP. Blood products were transfused to 35% of each cohort: 5,850 civilians received a transfusion with 2,118 (12.6%) of them receiving ≥10 units; 4,590 NNCPs received a transfusion with 1,669 (12.6%) receiving ≥ 10 units. MTF mortality rates were civilians 1,263 (7.5%) and NNCP 776 (5.9%). Interventions, both operative and non-operative, were similar between both groups.CONCLUSIONS: In accordance with International Humanitarian Law, as well as the US military's medical rules of eligibility, civilians injured in combat zones were provided the same level of care as non-NATO Coalition Personnel. Injured civilians and NNCP had similar mechanisms of injury, injury patterns, transfusion needs, and ISS. This analysis demonstrates resource equipoise in trauma care delivered to civilians and NNCP. Hospitals in combat zones must be prepared to manage large numbers of civilian casualties with significant human and material resources allocated to optimize survival. The provision of humanitarian trauma care is resource-intensive, and these data can be used to inform planning factors for current or future humanitarian care in combat zones.

  View details for DOI 10.1097/SLA.0000000000005592

  View details for PubMedID 35837945

• Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members (vol 17, 34, 2022) WORLD JOURNAL OF EMERGENCY SURGERY Reichert, M., Sartelli, M., Weigand, M. A., Hecker, M., Oppelt, P. U., Noll, J., Askevold, I. H., Liese, J., Padberg, W., Coccolini, F., Catena, F., Hecker, A., WSES COVID-19 Emergency Surg Surve 2022; 17 (1): 39

  View details for DOI 10.1186/s13017-022-00442-y

  View details for Web of Science ID 000825760900002

  View details for PubMedID 35804425

  View details for PubMedCentralID PMC9270731

• Assessment of Second Primary Cancer Risk Among Men Receiving Primary Radiotherapy vs Surgery for the Treatment of Prostate Cancer. JAMA network open Bagshaw, H. P., Arnow, K. D., Trickey, A. W., Leppert, J. T., Wren, S. M., Morris, A. M. 2022; 5 (7): e2223025

  Abstract

  Shared decision-making is an important part of the treatment selection process among patients with prostate cancer. Updated information is needed regarding the long-term incidence and risk of second primary cancer after radiotherapy vs nonradiotherapy treatments, which may help to inform discussions of risks and benefits for men diagnosed with prostate cancer.To assess the current incidence and risk of developing a second primary cancer after receipt of radiotherapy vs nonradiotherapy treatments for prostate cancer.This retrospective cohort study used the Veterans Affairs Corporate Data Warehouse to identify 154 514 male veterans 18 years and older who had localized prostate cancer (tumor stages T1-T3) diagnosed between January 1, 2000, and December 31, 2015, and no cancer history. A total of 10 628 patients were excluded because of (1) incomplete treatment information for the year after diagnosis, (2) receipt of both radiotherapy and a surgical procedure in the year after diagnosis, (3) receipt of radiotherapy more than 1 year after diagnosis, (4) occurrence of second primary cancer or death within 1 year or less after diagnosis, (5) prostate-specific antigen value greater than 99 ng/mL within 6 months before diagnosis, or (6) no recorded Veterans Health Administration service after diagnosis. The remaining 143 886 patients included in the study had a median (IQR) follow-up of 9 (6-13) years. Data were analyzed from May 1, 2021, to May 22, 2022.Diagnosis of a second primary cancer more than 1 year after prostate cancer diagnosis.Among 143 886 male veterans (median [IQR] age, 65 [60-71] years) with localized prostate cancer, 750 (0.5%) were American Indian or Alaska Native, 389 (0.3%) were Asian, 37 796 (26.3%) were Black or African American, 933 (0.6%) were Native Hawaiian or other Pacific Islander, 91 091 (63.3%) were White, and 12 927 (9.0%) were of unknown race; 7299 patients (5.1%) were Hispanic or Latino, 128 796 (89.5%) were not Hispanic or Latino, and 7791 (5.4%) were of unknown ethnicity. A total of 52 886 patients (36.8%) received primary radiotherapy, and 91 000 (63.2%) did not. A second primary cancer more than 1 year after prostate cancer diagnosis was present in 4257 patients (3.0%), comprising 1955 patients (3.7%) in the radiotherapy cohort and 2302 patients (2.5%) in the nonradiotherapy cohort. In the multivariable analyses, patients in the radiotherapy cohort had a higher risk of second primary cancer compared with those in the nonradiotherapy cohort at years 1 to 5 after diagnosis (hazard ratio [HR], 1.24; 95% CI, 1.13-1.37; P < .001), with higher adjusted HRs in the subsequent 15 years (years 5-10: 1.50 [95% CI, 1.36-1.65; P < .001]; years 10-15: 1.59 [95% CI, 1.37-1.84; P < .001]; years 15-20: 1.47 [95% CI, 1.08-2.01; P = .02).In this cohort study, patients with prostate cancer who received radiotherapy were more likely to develop a second primary cancer than patients who did not receive radiotherapy, with increased risk over time. Although the incidence and risk of developing a second primary cancer were low, it is important to discuss the risk with patients during shared decision-making about prostate cancer treatment options.

  View details for DOI 10.1001/jamanetworkopen.2022.23025

  View details for PubMedID 35900763

• Two years later: Is the SARS-CoV-2 pandemic still having an impact on emergency surgery? An international cross-sectional survey among WSES members WORLD JOURNAL OF EMERGENCY SURGERY Reichert, M., Sartelli, M., Weigand, M. A., Hecker, M., Oppelt, P. U., Noll, J., Askevold, I. H., Liese, J., Padberg, W., Coccolini, F., Catena, F., Hecker, A., WSES COVID-19 Emergency Surg Surve 2022; 17 (1): 34

  Abstract

  The SARS-CoV-2 pandemic is still ongoing and a major challenge for health care services worldwide. In the first WSES COVID-19 emergency surgery survey, a strong negative impact on emergency surgery (ES) had been described already early in the pandemic situation. However, the knowledge is limited about current effects of the pandemic on patient flow through emergency rooms, daily routine and decision making in ES as well as their changes over time during the last two pandemic years. This second WSES COVID-19 emergency surgery survey investigates the impact of the SARS-CoV-2 pandemic on ES during the course of the pandemic.A web survey had been distributed to medical specialists in ES during a four-week period from January 2022, investigating the impact of the pandemic on patients and septic diseases both requiring ES, structural problems due to the pandemic and time-to-intervention in ES routine.367 collaborators from 59 countries responded to the survey. The majority indicated that the pandemic still significantly impacts on treatment and outcome of surgical emergency patients (83.1% and 78.5%, respectively). As reasons, the collaborators reported decreased case load in ES (44.7%), but patients presenting with more prolonged and severe diseases, especially concerning perforated appendicitis (62.1%) and diverticulitis (57.5%). Otherwise, approximately 50% of the participants still observe a delay in time-to-intervention in ES compared with the situation before the pandemic. Relevant causes leading to enlarged time-to-intervention in ES during the pandemic are persistent problems with in-hospital logistics, lacks in medical staff as well as operating room and intensive care capacities during the pandemic. This leads not only to the need for triage or transferring of ES patients to other hospitals, reported by 64.0% and 48.8% of the collaborators, respectively, but also to paradigm shifts in treatment modalities to non-operative approaches reported by 67.3% of the participants, especially in uncomplicated appendicitis, cholecystitis and multiple-recurrent diverticulitis.The SARS-CoV-2 pandemic still significantly impacts on care and outcome of patients in ES. Well-known problems with in-hospital logistics are not sufficiently resolved by now; however, medical staff shortages and reduced capacities have been dramatically aggravated over last two pandemic years.

  View details for DOI 10.1186/s13017-022-00424-0

  View details for Web of Science ID 000812228600002

  View details for PubMedID 35710386

  View details for PubMedCentralID PMC9202986

• Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study LANCET GLOBAL HEALTH Knight, S. R., Chu, K., Lapitan, M., Dare, A. J., Pius, R., Shaw, C. A., Drake, T. M., Norman, L., Ademuyiwa, A. O., Adisa, A. O., Aguilera, M., Al-Saqqa, S. W., Al-Slaibi, I., Bhangu, A., Biccard, B. M., Brocklehurst, P., Costas-Chavarri, A., Elhadi, M., Fairfield, C. J., Fitzgerald, J., Ghosh, D., Glasbey, J., Henegouwen, M., Ingabire, J., Kingham, T., Lawani, I., Lieske, B., Lilford, R., Martin, J., Mclean, K. A., Moore, R., Morton, D., Nepogodiev, D., Ntirenganya, F., Pata, F., Pinkney, T., Qureshi, A., Ramos-De la Medina, A., Riad, A., Salem, H., Simoes, J., Spence, R., Smart, N., Tabiri, S., Thomas, H., West, M., Whitaker, J., Weiser, T. G., Harrison, E. M., GlobalSurg Collaborative, NIHR Global Hlth Res Unit Global S 2022; 10 (7): E1003-E1011

  Abstract

  Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58-5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23-0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised.National Institute for Health and Care Research.

  View details for DOI 10.1016/S2214-109X(22)00168-1

  View details for Web of Science ID 000835720300001

  View details for PubMedID 35623378

  View details for PubMedCentralID PMC9210173

• Exploration of Clinician Perspectives on Multidisciplinary Tumor Board Function Beyond Clinical Decision-making. JAMA oncology Wong, B. O., Blythe, J. A., Wu, A., Batten, J. N., Kennedy, K. M., Kouaho, A. S., Wren, S. M. 2022

  View details for DOI 10.1001/jamaoncol.2022.1763

  View details for PubMedID 35653129

• Perceptions of Gender Disparities in Access to Surgical Care in Malawi: A Community Based Survey. The American surgeon Reid, T., Kincaid, J., Shrestha, R., Strassle, P. D., Maine, R., Charles, A., Gallaher, J., Manjolo, M., Gondwe, J., Wren, S. M. 2022: 31348221101522

  Abstract

  BACKGROUND: Gender disparities in surgical care exist but have been minimally studied, particularly in low- and middle-income countries. This study explored perceptions and gender differences in health-seeking behavior and attitudes toward surgical care in Malawi among community members.METHODS: A survey tool was administered to adults ≥18years old at a central hospital, district hospital, and two marketplaces in Malawi from June 2018 to December 2018. Responses from men and women were compared using chi-squared tests.RESULTS: Four hundred eighty-five adults participated in the survey, 244 (50.3%) men and 241 (49.7%) women. Women were more likely to state that fear of surgery might prevent them from seeking surgical care (29.1% of men, 43.6% of women, P = .0009). Both genders reported long wait times, medicine/physician shortages, and lack of information about when surgery is needed as potential barriers to seeking surgical care. More men stated that medical preference should be given to sons (17.1% of men, 9.3% of women, P = .01). Men were more likely to report that men should have the final word about household decisions (28.7% of men vs 19.5% of women, P < .0001) and were more likely to spend money independently (68.7% of married men, 37.5% of married women, P < .0001). Few participants reported believing gender equality had been achieved (61% of men and 66.8% of women).CONCLUSIONS: A multi-pronged approach is needed to reduce gender disparities in surgical care in Malawi, including addressing paternalistic societal norms, education, and improving health infrastructure.

  View details for DOI 10.1177/00031348221101522

  View details for PubMedID 35592895

• Aspiring to Heal All with Skill and Trust. Journal of the American College of Surgeons Casey, K. M., Wren, S. M. 2022; 234 (2): 247

  View details for DOI 10.1097/XCS.0000000000000045

  View details for PubMedID 35213447

• Intraoperative bile spillage as a risk factor for surgical site infection: a propensity score-matched NSQIP analysis. Surgical endoscopy Russell, D., Condon, F., Cole, W., Wren, S., Yheulon, C. 1800

  Abstract

  BACKGROUND: Laparoscopic cholecystectomy is one of the most commonly performed operations in the USA. Surgical site infection complicates 1-2% of these operations and can be associated with significant morbidity. Bile spillage (bile spillage) occurs in many of these operations. The associated risk of surgical site infection (SSI) is an ongoing area of research.METHODS: NSQIP registries between 2005 and 2018 were queried using Current Procedural Terminology codes 47,562 and 47,563 to identify patients undergoing elective laparoscopic cholecystectomy. Patients were considered to have bile spillage if the wound classification was annotated 3 or 4. Acute cholecystitis was excluded by ICD code. Patients were propensity scored for bile spillage and matched for preoperative risk factors. The rates of surgical site infections, morbidity, and mortality and length of stay were analyzed.RESULTS: 47,919 (31,946 with no spillage and 15,973 with spillage) patients were matched and included in the analysis. After matching, no significant difference was found in superficial or deep SSI regardless of bile spillage. An absolute increase in organ-space SSI of 0.32% was detected. The group with bile spillage had small increases in both minor (1.41% vs.2.12%) and major (0.67% vs.1.01%) complications. There was no difference in mortality.CONCLUSIONS: This database analysis demonstrates no clinically relevant difference in surgical site infection rates after intraoperative bile spillage.

  View details for DOI 10.1007/s00464-021-08875-3

  View details for PubMedID 34988739

• Analysis of Registered Clinical Trials in Surgical Oncology, 2008-2020. JAMA network open Wong, B. O., Perera, N. D., Shen, J. Z., Turner, B. E., Litt, H. K., Mahipal, A., Wren, S. M. 1800; 5 (1): e2145511

  View details for DOI 10.1001/jamanetworkopen.2021.45511

  View details for PubMedID 35084485

• Effectiveness of emergency general surgery - some answers, more questions. Anaesthesia Forrester, J. D., Wren, S. M. 2022

  View details for DOI 10.1111/anae.15719

  View details for PubMedID 35307814

• Trends in US Surgical Procedures and Health Care System Response to Policies Curtailing Elective Surgical Operations During the COVID-19 Pandemic. JAMA network open Mattingly, A. S., Rose, L., Eddington, H. S., Trickey, A. W., Cullen, M. R., Morris, A. M., Wren, S. M. 2021; 4 (12): e2138038

  Abstract

  Importance: The COVID-19 pandemic has affected every aspect of medical care, including surgical treatment. It is critical to understand the association of government policies and infection burden with surgical access across the United States.Objective: To describe the change in surgical procedure volume in the US after the government-suggested shutdown and subsequent peak surge in volume of patients with COVID-19.Design, Setting, and Participants: This retrospective cohort study was conducted using administrative claims from a nationwide health care technology clearinghouse. Claims from pediatric and adult patients undergoing surgical procedures in 49 US states within the Change Healthcare network of health care institutions were used. Surgical procedure volume during the 2020 initial COVID-19-related shutdown and subsequent fall and winter infection surge were compared with volume in 2019. Data were analyzed from November 2020 through July 2021.Exposures: 2020 policies to curtail elective surgical procedures and the incidence rate of patients with COVID-19.Main Outcomes and Measures: Incidence rate ratios (IRRs) were estimated from a Poisson regression comparing total procedure counts during the initial shutdown (March 15 to May 2, 2020) and subsequent COVID-19 surge (October 22, 2020-January 31, 2021) with corresponding 2019 dates. Surgical procedures were analyzed by 11 major procedure categories, 25 subcategories, and 12 exemplar operative procedures along a spectrum of elective to emergency indications.Results: A total of 13 108 567 surgical procedures were identified from January 1, 2019, through January 30, 2021, based on 3498 Current Procedural Terminology (CPT) codes. This included 6 651 921 procedures in 2019 (3 516 569 procedures among women [52.9%]; 613 192 procedures among children [9.2%]; and 1 987 397 procedures among patients aged ≥65 years [29.9%]) and 5 973 573 procedures in 2020 (3 156 240 procedures among women [52.8%]; 482 637 procedures among children [8.1%]; and 1 806 074 procedures among patients aged ≥65 years [30.2%]). The total number of procedures during the initial shutdown period and its corresponding period in 2019 (ie, epidemiological weeks 12-18) decreased from 905 444 procedures in 2019 to 458 469 procedures in 2020, for an IRR of 0.52 (95% CI, 0.44 to 0.60; P<.001) with a decrease of 48.0%. There was a decrease in surgical procedure volume across all major categories compared with corresponding weeks in 2019. During the initial shutdown, otolaryngology (ENT) procedures (IRR, 0.30; 95% CI, 0.13 to 0.46; P<.001) and cataract procedures (IRR, 0.11; 95% CI, -0.11 to 0.32; P=.03) decreased the most among major categories. Organ transplants and cesarean deliveries did not differ from the 2019 baseline. After the initial shutdown, during the ensuing COVID-19 surge, surgical procedure volumes rebounded to 2019 levels (IRR, 0.97; 95% CI, 0.95 to 1.00; P=.10) except for ENT procedures (IRR, 0.70; 95% CI, 0.65 to 0.75; P<.001). There was a correlation between state volumes of patients with COVID-19 and surgical procedure volume during the initial shutdown (r=-0.00025; 95% CI, -0.0042 to -0.0009; P=.003), but there was no correlation during the COVID-19 surge (r=-0.00034; 95% CI, -0.0075 to 0.00007; P=.11).Conclusions and Relevance: This study found that the initial shutdown period in March through April 2020, was associated with a decrease in surgical procedure volume to nearly half of baseline rates. After the reopening, the rate of surgical procedures rebounded to 2019 levels, and this trend was maintained throughout the peak burden of patients with COVID-19 in fall and winter; these findings suggest that after initial adaptation, health systems appeared to be able to self-regulate and function at prepandemic capacity.

  View details for DOI 10.1001/jamanetworkopen.2021.38038

  View details for PubMedID 34878546

• Study on augmented reality for robotic surgery bedside assistants. Journal of robotic surgery Stewart, C. L., Fong, A., Payyavula, G., DiMaio, S., Lafaro, K., Tallmon, K., Wren, S., Sorger, J., Fong, Y. 2021

  Abstract

  Robotic surgery bedside assistants play an important role in robotic procedures by performing intra-corporeal tasks while accommodating the physical presence of the robot. We hypothesized that an augmented reality headset enabling 3D intra-corporeal vision while facing the surgical field could decrease time and improve accuracy of robotic bedside tasks. Bedside assistants (one physician assistant, one medical student, three surgical trainees, and two attending surgeons) performed validated tasks within a mock abdominal cavity with a surgical robot docked. Tasks were performed with a bedside monitor providing 2D or 3D vision, or an optical see-through head-mounted augmented reality device with 2D or 3D vision. The effect of augmented reality device resolution on performance was also evaluated. For the simplest task of touching a straw, performance was generally high, regardless of mode of visualization. With more complex tasks, including stapling and pulling a ring along a path, 3D augmented reality decreased time and number of errors per task. 3D augmented reality allowed the physician assistant to perform at the level of an attending surgeon using 3D augmented reality (p=0.08). All participants had improved times for the ring path task with better resolution (lower resolution 23±11s vs higher resolution 14±4s, p=0.002). 3D augmented reality vision with high resolution decreased time and improved accuracy of more complex tasks, enabling a less experienced robotic surgical bedside assistant to function similar to attending surgeons. These data warrant further study with additional complex tasks and bedside assistants at various levels of training.

  View details for DOI 10.1007/s11701-021-01335-z

  View details for PubMedID 34762249

• Advances in Appropriate Postoperative Triage and the Role of Real-time Machine-Learning Models: The Goldilocks Dilemma. JAMA network open Ko, A., Wren, S. M. 2021; 4 (11): e2133843

  View details for DOI 10.1001/jamanetworkopen.2021.33843

  View details for PubMedID 34757414

• Disparities in Outcomes after Emergency Surgery in the Rio Grande Valley of Texas Chavez, J. C., Wren, S. M., Knowlton, L. M. ELSEVIER SCIENCE INC. 2021: S129-S130

  View details for Web of Science ID 000718303100233

• The impact of operative approach on postoperative outcomes and healthcare utilization after colectomy. Surgery Mlambo, B., Shih, I., Li, Y., Wren, S. M. 2021

  Abstract

  BACKGROUND: To evaluate national trends in adoption of different surgical approaches for colectomy and compare clinical outcomes and resource utilization between approaches.METHODS: Retrospective study of patients aged ≥18 years who underwent elective inpatient left or right colectomy between 2010 and 2019 from the Premier Healthcare Database. Patients were classified by operative approach: open, minimally invasive: either laparoscopic or robotic. Postoperative outcomes assessed within index hospitalization include operating room time, hospital length of stay, rates of conversion to open surgery, reoperation, and complications. Post-discharge readmission, hospital-based encounters, and costs were collected to 30 days post-discharge. Multivariable regression models were used to compare outcomes between operative approaches adjusted for patient baseline characteristics and clustering within hospitals.RESULTS: Among 206,967 patients, the robotic approach rates increased from 2.1%/1.6% (2010) to 32.6%/26.8% (2019) for left/right colectomy, offset by a decrease in both open and laparoscopic approaches. Median length of stay for both left and right colectomies was significantly longer in open (6 days) and laparoscopic (5 days) compared to robotic surgery (4 days; all P values <.001). Robotic surgery compared to open and laparoscopic was associated with a significantly lower conversion rate, development of ileus, overall complications, and 30-day hospital encounters. Robotic surgery further demonstrated lower mortality, reoperations, postoperative bleeding, and readmission rates for left and right colectomies than open. Robotic surgery had significantly longer operating room times and higher costs than either open or laparoscopic.CONCLUSIONS: Robotic surgery is increasingly being used in colon surgery, with outcomes equivalent and in some domains superior to laparoscopic.

  View details for DOI 10.1016/j.surg.2021.07.011

  View details for PubMedID 34362589

• Identifying high-risk surgical patients: A study of older adults whose code status changed to Do-Not-Resuscitate. Journal of the American Geriatrics Society Kazaure, H. S., Truong, T., Kuchibhatla, M., Lagoo-Deenadayalan, S., Wren, S. M., Johnson, K. S. 2021

  Abstract

  BACKGROUND: There is a paucity of data on older adults (age ≥65years) undergoing surgery who had an inpatient do-not-resuscitate (DNR) order, and the association between timing of DNR order and outcomes.METHODS: This was a retrospective analysis of 1976 older adults in the American College of Surgeons National Surgical Quality Improvement Program geriatric-specific database (2014-2018). Patients were stratified by institution of a DNR order during their surgical admission ("new-DNR" vs. "no-DNR"), and matched by age (±3years), frailty score (range: 0-1), and procedure. The main outcome of interest was occurrence of death or hospice transition (DoH) ≤30 postoperative days; this was analyzed using bivariate and multivariable methods.RESULTS: One in 36 older adults had a new-DNR order. After matching, there were 988 new-DNR and 988 no-DNR patients. Median age and frailty score were 82years and 0.2, respectively. Most underwent orthopedic (47.6%), general (37.6%), and vascular procedures (8.4%). Overall DoH rate ≤30days was 44.4% for new-DNR versus 4.0% for no-DNR patients (p<0.001). DoH rate for patients who had DNR orders placed in the preoperative, day of surgery, and postoperative setting was 16.7%, 23.3%, and 64.6%, respectively (p<0.001). In multivariable analysis, compared to no-DNR patients, those with a new-DNR order had a 28-fold higher adjusted odds of DoH (odds ratio [OR] 28.1, 95% confidence interval: 13.0-60.1, p<0.001); however, odds were 10-fold lower if the DNR order was placed preoperatively (OR: 5.8, p=0.003) versus postoperatively (OR: 52.9, p<0.001). Traditional markers of poor postoperative outcomes such as American Society of Anesthesiologists class and emergency surgery were not independently associated with DoH.CONCLUSIONS: An inpatient DNR order was associated with risk of DoH independent of traditional markers of poor surgical outcomes. Further research is needed to understand factors leading to a DNR order that may aid early recognition of high-risk older adults undergoing surgery.

  View details for DOI 10.1111/jgs.17391

  View details for PubMedID 34331702

• Local Staff Perceptions and Expectations of International Visitors in Global Surgery Rotations. JAMA surgery Mulenga, M., Rhodes, Z., Wren, S. M., Parikh, P. P. 2021

  View details for DOI 10.1001/jamasurg.2021.2861

  View details for PubMedID 34259805

• THE IMPACT OF OPERATIVE APPROACH ON POSTOPERATIVE OUTCOMES AND HEALTH CARE UTILIZATION FOLLOWING COLECTOMY Mlambo, B., Shih, I. F., Li, Y., Wren, S. ELSEVIER SCIENCE INC. 2021: S224

  View details for Web of Science ID 000660039401245

• Counting the costs of trauma: the need for a new paediatric injury severity score. The Lancet. Child & adolescent health Sargent, W., Wild, H., Mayhew, E., Wren, S. M. 2021; 5 (6): 391-392

  View details for DOI 10.1016/S2352-4642(21)00132-2

  View details for PubMedID 34019790

• Counting the costs of trauma: the need for a new paediatric injury severity score LANCET CHILD & ADOLESCENT HEALTH Sargent, W., Wild, H., Mayhew, E., Wren, S. M. 2021; 5 (6): 391-392

  View details for Web of Science ID 000653480600010

• The surgical oncology clinical trial landscape: A cross-sectional analysis of ClinicalTrials.gov from 2008-2020. Perera, N. D., Turner, B. E., Shen, J. Z., Wong, B. O., Litt, H. K., Stavins, M. A., Bellomo, T. R., Saleki, M., Bell, A., Ionescu, R., Shyu, M., Wang, M. M., Tao, J., Sarsour, N., O'Keefe, R. M., Takasugi, J. M., Steinberg, J. R., King, R., Mahipal, A., Wren, S. M. LIPPINCOTT WILLIAMS & WILKINS. 2021

  View details for DOI 10.1200/JCO.2021.39.15_suppl.1561

  View details for Web of Science ID 000708120600260

• Improvements and Gaps in Financial Risk Protection Among Veterans Following the Affordable Care Act. Journal of general internal medicine Liu, C., Scannell, C. A., Kenison, T., Wren, S. M., Saliba, D. 2021

  Abstract

  BACKGROUND: Despite public perception, most of the nearly 20 million US veterans have health coverage outside the Veterans Health Administration (VHA), and VHA eligibility and utilization vary across veterans. Out-of-pocket healthcare spending thus remains a potential source of financial hardship for veterans. The Affordable Care Act (ACA) aimed to expand health insurance access, but its effect on veterans' financial risk protection has not been explored.OBJECTIVE: To evaluate whether ACA implementation was associated with changes in veterans' risk of catastrophic health expenditures, and to characterize drivers of catastrophic health spending among veterans post-ACA.DESIGN: Using multivariable linear probability regression, we examined changes in likelihood of catastrophic health spending after ACA implementation, stratifying by age (18-64 vs 65+), household income tercile, and payer (VHA vs non-VHA). Among veterans with catastrophic spending post-ACA, we evaluated sources of out-of-pocket spending.PARTICIPANTS: Nationally representative sample of 13,030 veterans aged 18+ from the 2010 to 2017 Medical Expenditure Panel Survey.INTERVENTION: ACA implementation, January 1, 2014.MAIN MEASURES: Likelihood of catastrophic health expenditures, defined as household out-of-pocket spending exceeding 10% of household income.KEY RESULTS: Among veterans aged 18-64, ACA implementation was associated with a 26% decrease in likelihood of catastrophic health expenditures (absolute change, -1.4 percentage points [pp]; 95% CI, -2.6 to -0.2; p=0.03), which fell from 5.4% pre-ACA to 3.9% post-ACA. This was driven by a 38% decrease in catastrophic spending among veterans with non-VHA coverage (absolute change, -1.8pp; 95% CI, -3.0 to -0.6; p=0.003). In contrast, catastrophic expenditure rates among veterans aged 65+ remained high, at 13.0% pre- and 12.5% post-ACA. Major drivers of veterans' spending post-ACA include dental care, prescription drugs, and home care.CONCLUSIONS: ACA implementation was associated with reduced householdcatastrophic health expenditures for younger but not older veterans. These findings highlight gaps in veterans' financial protection and areas amenable to policy intervention.

  View details for DOI 10.1007/s11606-021-06807-4

  View details for PubMedID 33959882

• Pediatric casualties in contemporary armed conflict: A systematic review to inform standardized reporting. Injury Wild, H., Stewart, B. T., LeBoa, C., Stave, C. D., Wren, S. M. 2021

  Abstract

  BACKGROUND: Children represent a significant percentage of casualties in modern conflict. Yet, the epidemiology of conflict-related injury among children is poorly understood. A comprehensive analysis of injuries sustained by children in 21st-century armed conflict is necessary to inform planning of local, military, and humanitarian health responses.METHODS: We conducted a systematic search of databases including PubMed, Embase, Web of Science, World Health Organization Catalog, and Google Scholar to identify records that described conflict-related injuries sustained by children since 2001.RESULTS: The search returned 5,264 records. 9 eligible reports without potentially duplicative data were included in analysis, representing 5,100 pediatric patients injured in 5 conflicts. Blast injury was the most frequent mechanism (57%), compared to 24.8% in adults. Mortality was only slightly higher among children (11.0% compared to 9.8% among adults; p <0.05). Non-uniform reporting prevented pooled analysis and limited the conclusions that could be drawn.CONCLUSIONS: Children sustain a higher proportion of blast injury than adults in conflict. Existing data do support the conclusion that child casualties have higher mortality than adults overall; however, this difference is slighter than has been previously reported. Specific subpopulations of children appear to have worse outcomes. Overall, non-uniform reporting renders currently available data insufficient to understand the needs of children injured in modern conflict.

  View details for DOI 10.1016/j.injury.2021.04.055

  View details for PubMedID 34006405

• From Listening to Action: Academic Surgcial Departmental Response to Social Injustice Through Curricular Development. Annals of surgery Korndorffer, J. R., Wren, S. M., Pugh, C. M., Hawn, M. T. 2021

  Abstract

  OBJECTIVES: To describe the development and evaluation of a structured department wide cultural competency curriculum.SUMMARY BACKGROUND DATA: Despite numerous organizational policies and statements, social injustice and bias still exists. Our department committed to assist individuals of the entire department to develop foundational knowledge and skills to combat implicit bias and systemic racism through the creation of a cultural competency curriculum. The purpose of this manuscript is to detail our curriculum and the evaluation of its effectiveness.METHODS: Using a well-established curriculum development framework, a cultural competency curriculum was developed focusing on knowledge, skills and attitudes at the individual level, for all members of the department. The curriculum was implemented through six, hour-long sessions over a nine-week period. Effectiveness was assessed through a post curriculum survey.RESULTS: 20% of the respondents had experienced bias based on race, ethnicity or sexual orientation in the past 12 months while 30% had experienced bias based on gender. 71% independently explored related topics. The curriculum was overall well received and generally achieved the goals and objectives.CONCLUSIONS: Using a standard curriculum development framework, an effective department-wide cultural competency curriculum can be developed and implemented.

  View details for DOI 10.1097/SLA.0000000000004891

  View details for PubMedID 33856378

• Strong for Surgery: Association Between Bundled Risk Factors and Outcomes After Major Elective Surgery in the VA Population. World journal of surgery Liou, D. Z., Patel, D. C., Bhandari, P., Wren, S. M., Marshall, N. J., Harris, A. H., Shrager, J. B., Berry, M. F., Lui, N. S., Backhus, L. M. 2021

  Abstract

  BACKGROUND: Strong for Surgery (S4S) is a public health campaign focused on optimizing patient health prior to surgery by identifying evidence-based modifiable risk factors. The potential impact of S4S bundled risk factors on outcomes after major surgery has not been previously studied. This study tested the hypothesis that a higher number of S4S risk factors is associated with an escalating risk of complications and mortality after major elective surgery in the VA population.METHODS: The Veterans Affairs Surgical Quality Improvement Program (VASQIP) database was queried for patients who underwent major non-emergent general, thoracic, vascular, urologic, and orthopedic surgeries between the years 2008 and 2015. Patients with complete data pertaining to S4S risk factors, specifically preoperative smoking status, HbA1c level, and serum albumin level, were stratified by number of positive risk factors, and perioperative outcomes were compared.RESULTS: A total of 31,285 patients comprised the study group, with 16,630 (53.2%) patients having no S4S risk factors (S4S0), 12,323 (39.4%) having one (S4S1), 2,186 (7.0%) having two (S4S2), and 146 (0.5%) having three (S4S3). In the S4S1 group, 60.3% were actively smoking, 35.2% had HbA1c>7, and 4.4% had serum albumin<3. In the S4S2 group, 87.8% were smokers, 84.8% had HbA1c>7, and 27.4% had albumin<3. Major complications, reoperations, length of stay, and 30-day mortality increased progressively from S4S0 to S4S3 groups. S4S3 had the greatest adjusted mortality risk (adjusted odds radio [AOR] 2.56, p=0.04) followed by S4S2 (AOR 1.58, p=0.02) and S4S1 (AOR 1.34, p=0.02).CONCLUSION: In the VA population, patients who had all three S4S risk factors, namely active smoking, suboptimal nutritional status, and poor glycemic control, had the greatest risk of postoperative mortality compared to patients with fewer S4S risk factors.

  View details for DOI 10.1007/s00268-021-05979-8

  View details for PubMedID 33598723

• Publisher Correction to: The gender gap and healthcare: associations between gender roles and factors affecting healthcare access in Central Malawi, June-August 2017. Archives of public health = Archives belges de sante publique Azad, A. D., Charles, A. G., Ding, Q., Trickey, A. W., Wren, S. M. 2021; 79 (1): 19

  View details for DOI 10.1186/s13690-021-00538-y

  View details for PubMedID 33579368

• Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries LANCET Knight, S. R., Shaw, C. A., Pius, R., Drake, T. M., Norman, L., Ademuyiwa, A. O., Adisa, A. O., Aguilera-Arevalo, M., Al-Saqqa, S. W., Al-Slaibi, I. S., Bhangu, A., Biccard, B. M., Brocklehurst, P., Costas-Chavarri, A., Chu, K. M., Dare, A. J., Elhadi, M., Fairfield, C. J., Fitzgerald, J., Ghosh, D. N., Glasbey, J., Henegouwen, M., Ingabire, J., Kingham, T., Lapitan, M. M., Lawani, I., Lieske, B., Lilford, R. J., Martin, J., Mclean, K. A., Moore, R. L., Morton, D., Nepogodiev, D., Ntirenganya, F., Pata, F., Pinkney, T. D., Qureshi, A. U., Ramos-De la Medina, A., Riad, A. M., Salem, H., Simoes, J., Spence, R. T., Smart, N. J., Tabiri, S., Thomas, H. S., Weiser, T. G., West, M. A., Whitaker, J., Harrison, E. M., GlobalSurg Collaborative, Global Surg Writing Grp 2021; 397 (10272): 387–97

  Abstract

  80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality.This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494.Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70-8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39-8·80) and upper-middle-income countries (2·06, 1·11-3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26-11·59) and upper-middle-income countries (3·89, 2·08-7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications.Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications.National Institute for Health Research Global Health Research Unit.

  View details for DOI 10.1016/S0140-6736(21)00001-5

  View details for Web of Science ID 000614227700026

  View details for PubMedID 33485461

  View details for PubMedCentralID PMC7846817

• Translating Outcomes Data Into Improved Shared Decision-Making in Patients With Left Ventricular Assist Devices. JAMA network open Rajasingh, C. M., Wren, S. M. 2020; 3 (11): e2025673

  View details for DOI 10.1001/jamanetworkopen.2020.25673

  View details for PubMedID 33180126

• Task Dynamics of Prior Training Influence Visual Force Estimation Ability During Teleoperation IEEE TRANSACTIONS ON MEDICAL ROBOTICS AND BIONICS Chua, Z., Jarc, A. M., Wren, S. M., Nisky, I., Okamura, A. M. 2020; 2 (4): 586-597

  View details for DOI 10.1109/TMRB.2020.3023005

  View details for Web of Science ID 000896654300019

• Managing Central Venous Access during a Healthcare Crisis. Journal of vascular surgery Chun, T. T., Judelson, D. R., Rigberg, D., Lawrence, P. F., Cuff, R., Shalhub, S., Wohlauer, M., Abularrage, C. J., Anastasios, P., Arya, S., Aulivola, B., Baldwin, M., Baril, D., Bechara, C. F., Beckerman, W. E., Behrendt, C., Benedetto, F., Bennett, L. F., Charlton-Ouw, K. M., Chawla, A., Chia, M. C., Cho, S., Choong, A. M., Chou, E. L., Christiana, A., Coscas, R., De Caridi, G., Ellozy, S., Etkin, Y., Faries, P., Fung, A. T., Gonzalez, A., Griffin, C. L., Guidry, L., Gunawansa, N., Gwertzman, G., Han, D. K., Hicks, C. W., Hinojosa, C. A., Hsiang, Y., Ilonzo, N., Jayakumar, L., Joh, J. H., Johnson, A. P., Kabbani, L. S., Keller, M. R., Khashram, M., Koleilat, I., Krueger, B., Kumar, A., Lee, C. J., Lee, A., Levy, M. M., Lewis, C. T., Lind, B., Lopez-Pena, G., Mohebali, J., Molnar, R. G., Morrissey, N. J., Motaganahalli, R. L., Mouawad, N. J., Newton, D. H., Ng, J. J., O'Banion, L. A., Phair, J., Rancic, Z., Rao, A., Ray, H. M., Rivera, A. G., Rodriguez, L., Sales, C. M., Salzman, G., Sarfati, M., Savlania, A., Schanzer, A., Sharafuddin, M. J., Sheahan, M., Siada, S., Siracuse, J. J., Smith, B. K., Smith, M., Soh, I., Sorber, R., Sundaram, V., Sundick, S., Tomita, T. M., Trinidad, B., Tsai, S., Vouyouka, A. G., Westin, G. G., Williams, M. S., Wren, S. M., Yang, J. K., Yi, J., Zhou, W., Zia, S., Woo, K. 2020

  Abstract

  INTRODUCTION: During the COVID-19 pandemic, central venous access line teams were implemented at many hospitals throughout the world to provide access for critically ill patients. The objective of this study was to describe the structure, practice patterns and outcomes of these vascular access teams during the COVID-19 pandemic.METHODS: We conducted a cross sectional, self-reported study of central venous access line teams in hospitals afflicted with the COVID-19 pandemic. In order to participate in the study, hospitals were required to meet one of the following criteria: a) development of a formal plan for a central venous access line team during the pandemic, b) implementation of a central venous access line team during the pandemic, c) placement of central venous access by a designated practice group during the pandemic as part of routine clinical practice, or d) management of an iatrogenic complication related to central venous access in a patient with COVID-19.RESULTS: Participants from 60 hospitals in 13 countries contributed data to the study. Central venous line teams were most commonly composed of vascular surgery and general surgery attending physicians and trainees. Twenty sites had 2,657 lines placed by their central venous access line team or designated practice group. During that time, there were 11 (0.4%) iatrogenic complications associated with central venous access procedures performed by the line team or group at those 20 sites. Triple lumen catheters, Cordis catheters and non-tunneled hemodialysis catheters were the most common types of central venous lines placed by the teams. Eight (14%) sites reported experience placing central venous lines in prone, ventilated patients with COVID-19. A dedicated line cart was used by 35 (59%) of hospitals. Less than 50% (24, 41%) of the participating sites reported managing thrombosed central lines in COVID-patients. Twenty-three of the sites managed 48 iatrogenic complications in patients with COVID-19 (including complications caused by providers outside of the line team or designated practice group).CONCLUSIONS: Implementation of a dedicated central venous access line team during a pandemic or other healthcare crisis is a way by which physicians trained in central venous access can contribute their expertise to a stressed healthcare system. A line team composed of physicians with vascular skill sets provides relief to resource-constrained ICU, ward, and emergency medicine teams with a low rate of iatrogenic complications relative to historical reports. We recommend that a plan for central venous access line team implementation be in place for future healthcare crises.

  View details for DOI 10.1016/j.jvs.2020.06.112

  View details for PubMedID 32682063

• COVID-19 Preparedness within the Surgical, Obstetric and Anesthetic Ecosystem in Sub Saharan Africa. Annals of surgery Ademuyiwa, A. O., Bekele, A., Berhea, A. B., Borgstein, E., Capo-Chichi, N., Derbew, M., Evans, F. M., Feyssa, M. D., Galukande, M., Gawande, A. A., Gueye, S. M., Harrison, E., Jani, P., Kaseje, N., Litswa, L., Mammo, T. N., Mellin-Olsen, J., Muguti, G., Nabukenya, M. T., Ngoga, E., Ntirenganya, F., Rulisa, S., Starr, N., Tabiri, S., Tadesse, M., Walker, I., Weiser, T. G., Wren, S. M. 2020

  View details for DOI 10.1097/SLA.0000000000003964

  View details for PubMedID 32301806

• Applying trauma systems concepts to humanitarian battlefield care: a qualitative analysis of the Mosul trauma pathway. Conflict and health Garber, K. n., Kushner, A. L., Wren, S. M., Wise, P. H., Spiegel, P. B. 2020; 14: 5

  Abstract

  Trauma systems have been shown to save lives in military and civilian settings, but their use by humanitarians in conflict settings has been more limited. During the Battle of Mosul (October 2016-July 2017), trauma care for injured civilians was provided through a novel approach in which humanitarian actors were organized into a trauma pathway involving echelons of care, a key component of military trauma systems. A better understanding of this approach may help inform trauma care delivery in future humanitarian responses in conflicts.A qualitative study design was used to examine the Mosul civilian trauma response. From August-December 2017, in-depth semi-structured interviews were conducted with stakeholders (n = 54) representing nearly two dozen organizations that directly participated in or had first-hand knowledge of the response. Source document reviews were also conducted. Responses were analyzed in accordance with a published framework on civilian battlefield trauma systems, focusing on whether the response functioned as an integrated trauma system. Opportunities for improvement were identified.The Mosul civilian trauma pathway was implemented as a chain of care for civilian casualties with three successive echelons (trauma stabilization points, field hospitals, and referral hospitals). Coordinated by the World Health Organization, it comprised a variety of actors, including non-governmental organizations, civilian institutions, and at least one private medical company. Stakeholders generally felt that this approach improved access to trauma care for civilians injured near the frontlines compared to what would have been available. Several trauma systems elements such as transportation, data collection, field coordination, and post-operative rehabilitative care might have been further developed to support a more integrated system.The Mosul trauma pathway evolved to address critical gaps in trauma care during the Battle of Mosul. It adapted the concept of echelons of care from western military practice to push humanitarian actors closer to the frontlines and improve access to care for injured civilians. Although efforts were made to incorporate some of the integrative components (e.g. evidence-based pre-hospital care, transportation, and data collection) that have enabled recent achievements by military trauma systems, many of these proved difficult to implement in the Mosul context. Further discussion and research are needed to determine how trauma systems insights can be adapted in future humanitarian responses given resource, logistical, and security constraints, as well as to clarify the responsibilities of various actors.

  View details for DOI 10.1186/s13031-019-0249-2

  View details for PubMedID 32042308

  View details for PubMedCentralID PMC7001520

• Epidemiology of Injuries Sustained by Civilians and Local Combatants in Contemporary Armed Conflict: An Appeal for a Shared Trauma Registry Among Humanitarian Actors. World journal of surgery Wild, H. n., Stewart, B. T., LeBoa, C. n., Stave, C. D., Wren, S. M. 2020

  Abstract

  Conflict-related injuries sustained by civilians and local combatants are poorly described, unlike injuries sustained by US, North Atlantic Treaty Organization, and coalition military personnel. An understanding of injury epidemiology in twenty-first century armed conflict is required to plan humanitarian trauma systems capable of responding to population needs.We conducted a systematic search of databases (e.g., PubMed, Embase, Web of Science, World Health Organization Catalog, Google Scholar) and grey literature repositories to identify records that described conflict-related injuries sustained by civilians and local combatants since 2001.The search returned 3501 records. 49 reports representing conflicts in 18 countries were included in the analysis and described injuries of 58,578 patients. 79.3% of patients were male, and 34.7% were under age 18 years. Blast injury was the predominant mechanism (50.2%), and extremities were the most common anatomic region of injury (33.5%). The heterogeneity and lack of reporting of data elements prevented pooled analysis and limited the generalizability of the results. For example, data elements including measures of injury severity, resource utilization (ventilator support, transfusion, surgery), and outcomes other than mortality (disability, quality of life measures) were presented by fewer than 25% of reports.Data describing the needs of civilians and local combatants injured during conflict are currently inadequate to inform the development of humanitarian trauma systems. To guide system-wide capacity building and quality improvement, we advocate for a humanitarian trauma registry with a minimum set of data elements.

  View details for DOI 10.1007/s00268-020-05428-y

  View details for PubMedID 32100067

• Improving Outcomes After Surgery-An Old Medication With Unexpected Benefits. JAMA surgery George, E. L., Wren, S. M. 2020: e200417

  View details for DOI 10.1001/jamasurg.2020.0417

  View details for PubMedID 32267486

• Surgical Procedures in Veterans Affairs Hospitals During the COVID-19 Pandemic. Annals of surgery Rose, L. n., Mattingly, A. S., Morris, A. M., Trickey, A. W., Ding, Q. n., Wren, S. M. 2020; Publish Ahead of Print

  View details for DOI 10.1097/SLA.0000000000004692

  View details for PubMedID 33351471

• The gender gap and healthcare: associations between gender roles and factors affecting healthcare access in Central Malawi, June-August 2017. Archives of public health = Archives belges de sante publique Azad, A. D., Charles, A. G., Ding, Q. n., Trickey, A. W., Wren, S. M. 2020; 78 (1): 119

  Abstract

  Women in low and middle-income countries (LMICs) do not have equal access to resources, such as education, employment, or healthcare compared to men. We sought to explore health disparities and associations between gender prioritization, sociocultural factors, and household decision-making in Central Malawi.From June-August 2017, a cross-sectional study with 200 participants was conducted in Central Malawi. We evaluated respondents' access to care, prioritization within households, decision-making power, and gender equity which was measured using the Gender-Equitable Men (GEM) scale. Relationships between these outcomes and sociodemographic factors were analyzed using multivariable mixed-effect logistic regression.We found that women were less likely than men to secure community-sourced healthcare financial aid (68.6% vs. 88.8%, p < 0.001) and more likely to underutilize necessary healthcare (37.2% vs. 22.4%, p = 0.02). Both men and women revealed low GEM scores, indicating adherence to traditional gender norms, though women were significantly less equitable (W:16.77 vs. M:17.65, p = 0.03). Being a woman (Odds Ratio (OR) 0.41, 95% confidence interval (CI) 0.21-0.78) and prioritizing a woman as a decision-maker for large purchases (OR 0.38, CI 0.15-0.93) were independently associated with a lower likelihood of prioritizing women for medical treatment and being a member of the Chewa tribal group (OR 3.87, CI 1.83-8.18) and prioritizing women for education (OR 4.13, CI 2.13-8.01) was associated with a higher odds.Women report greater barriers to healthcare and adhere to more traditional gender roles than men in this Central Malawian population. Women contribute to their own gender's barriers to care and economic empowerment alone is not enough to correct for these socially constructed roles. We found that education and matriarchal societies may protect against gender disparities. Overall, internal and external gender discrimination contribute to a woman's disproportionate lack of access to care.

  View details for DOI 10.1186/s13690-020-00497-w

  View details for PubMedID 33292511

• Optimizable Risk Factors Contributing to Mortality in Patients With Heart Failure Undergoing Noncardiac Surgery. JAMA surgery Lerman, B. J., Livingston, E. H., Wren, S. M. 2020

  View details for DOI 10.1001/jamasurg.2020.0257

  View details for PubMedID 32267503

• USA Department of Defense audit of surgical antibiotic prophylaxis prescribing patterns in inguinal hernia repair. Hernia : the journal of hernias and abdominal wall surgery Russell, D. n., Cole, W. n., Yheulon, C. n., Wren, S. n., Kellicut, D. n., Lim, R. n. 2020

  Abstract

  Antibiotic prophylaxis in inguinal hernia repair (IHR) is contentious in literature and practice. In low-risk patients, for whom evidence suggests antibiotic prophylaxis is unnecessary, many surgeons still advocate for its routine use. This study surveys prescription patterns of Department of Defense (DoD) general surgeons.An anonymous survey was sent electronically to approximately 350 DoD general surgeons. The survey asked multiple-choice and free text answers about prescribing patterns and knowledge of current evidence for low-risk patients undergoing elective open inguinal hernia repair without mesh (OIHRWOM), open inguinal hernia repair with mesh (OIHRWM), or laparoscopic inguinal hernia repair (LIHR).110 DoD general surgeons consented to participate. 58.6, 95 and 84.2% of surgeons always administer antibiotic prophylaxis in OIHRWOM, OIHRWM, and LIHR, respectively. 37.9, 70.9, and 63.2% of surgeons believe that it reduces rates of surgical site infection in OIHRWOM, OIHRWM, and LIHR, respectively. The most common reasons for empirically prescribing antibiotic prophylaxis include "I think the evidence supports it" (27 of 72 responses), "I would rather be conservative and safe" (15 of 72 responses), and "I am following my hospital/department guidelines" (9 of 72 responses). 11.8, 40.8, and 32.9% of surgeons believe current evidence supports antibiotic prophylaxis use in OIHRWM, OIHRWOM, and LIHR, respectively. 50, 18.4, and 22.4% of surgeons believe current evidence refutes antibiotic prophylaxis use in OIHRWM, OIHRWOM, and LIHR, respectively.The survey results indicate that the majority of practicing DoD general surgeons still empirically prescribe surgical antibiotic prophylaxis in IHR despite more conflicting opinions that it has no meaningful effect or that current evidence does not supports its use.

  View details for DOI 10.1007/s10029-020-02145-2

  View details for PubMedID 32107656

• Association of Sex With Postoperative Mortality Among Patients With Heart Failure Who Underwent Elective Noncardiac Operations. JAMA network open Mattingly, A. S., Lerman, B. J., Popat, R., Wren, S. M. 2019; 2 (11): e1914420

  Abstract

  Importance: Sex differences in postoperative outcomes in patients with heart failure (HF) have not been well characterized. Women generally experience a lower postoperative mortality risk after noncardiac operations. It is unclear if this pattern holds among patients with HF.Objectives: To determine if the risk of postoperative mortality is associated with sex among patients with HF who underwent noncardiac operations and to determine if sex is associated with the relationship between HF and postoperative mortality.Design, Setting, and Participants: This multisite cohort study used data from the US Department of Veterans Affairs Surgical Quality Improvement Project database for all patients who underwent elective noncardiac operations from October 1, 2009, to September 30, 2016, with a minimum of 1 year follow-up. The data analysis was conducted from May 1, 2018, to August 31, 2018.Exposures: Heart failure, left ventricular ejection fraction, and sex.Main Outcomes and Measures: Postoperative mortality at 90 days.Results: Among 609 735 patients who underwent elective noncardiac operations from 2009 to 2016, 47 997 patients had HF (7.9%; mean [SD] age, 68.6 [10.1] years; 1391 [2.9%] women) and 561 738 patients did not have HF (92.1%; mean [SD] age, 59.4 [13.4] years; 50 862 [9.1%] women). Among patients with HF, female sex was not independently associated with 90-day postoperative mortality (adjusted odds ratio [aOR], 0.97; 95% CI, 0.71-1.32). Although HF was associated with increased odds of postoperative mortality in both sexes compared with their peers without HF, the odds of postoperative mortality were higher among women with HF (aOR, 2.44; 95% CI, 1.73-3.45) than men with HF (aOR, 1.64; 95% CI, 1.54-1.74), suggesting that HF may negate the general protective association of female sex with postoperative mortality (P for interaction of HF*sex=.03). This pattern was consistent across all levels of left ventricular ejection fraction.Conclusions and Relevance: Although HF was associated with increased odds of postoperative mortality in both sexes compared with their peers without HF, the odds of postoperative mortality were higher among women with HF than men with HF, suggesting that HF may negate the general protective association of female sex with postoperative mortality risk in noncardiac operations.

  View details for DOI 10.1001/jamanetworkopen.2019.14420

  View details for PubMedID 31675085

• The Realities of External Validity in Global Surgery Research-Reply. JAMA surgery Wren, S. M., Kushner, A. L. 2019

  View details for DOI 10.1001/jamasurg.2019.4090

  View details for PubMedID 31642875

• Operating room preparedness for active shooter events. Surgery Leppert, J. T., Wren, S. M., Bergman, J. 2019

  View details for DOI 10.1016/j.surg.2019.08.009

  View details for PubMedID 31606195

• Sex Disparities in Access to Surgical Care in Malawi: A Community- and Hospital-Based Survey Kincaid, J. A., Maine, R. G., Wren, S. M., Manjolo, M., Gondwe, J., Charles, A. G., Reid, T. ELSEVIER SCIENCE INC. 2019: S137–S138

  View details for Web of Science ID 000492740900252

• Global Action Needed to Protect Humanitarian Surgeons and Patients During Wars and Armed Conflicts-Reply. JAMA surgery Wren, S. M., Schussler, L., Burkle, F. M. 2019

  View details for DOI 10.1001/jamasurg.2019.3501

  View details for PubMedID 31532473

• Academic Advancement in Global Surgery: Appointment, Promotion, and Tenure: Recommendations from the American Surgical Association Working Group on Global Surgery. Annals of surgery Wren, S. M., Balch, C. M., Doherty, G. M., Finlayson, S. R., Kauffman, G. L., Kibbe, M. R., Haider, A. H., Minter, R. M., Mock, C., Muguti, G. I., Numann, P. J., Olutoye, O. O., Roy, N., Weigel, R. J. 2019

  Abstract

  : There is growing interest in global surgery among US academic surgical departments. As academic global surgery is a relatively new field, departments may have minimal experience in evaluation of faculty contributions and how they integrate into the existing academic paradigm for promotion and tenure. The American Surgical Association Working Group on Global Surgery has developed recommendations for promotion and tenure in global surgery, highlighting criteria that: (1) would be similar to usual promotion and tenure criteria (eg, publications); (2) would likely be undervalued in current criteria (eg, training, administrative roles, or other activities that are conducted at low- and middle-income partner institutions and promote the partnerships upon which other global surgery activities depend); and (3) should not be considered (eg, mission trips or other clinical work, if not otherwise linked to funding, training, research, or building partnerships).

  View details for DOI 10.1097/SLA.0000000000003480

  View details for PubMedID 31356270

• Association Between Heart Failure and Postoperative Mortality Among Patients Undergoing Ambulatory Noncardiac Surgery. JAMA surgery Lerman, B. J., Popat, R. A., Assimes, T. L., Heidenreich, P. A., Wren, S. M. 2019

  Abstract

  Importance: Heart failure is an established risk factor for postoperative mortality, but how heart failure is associated with operative outcomes specifically in the ambulatory surgical setting is not well characterized.Objective: To assess the risk of postoperative mortality and complications in patients with vs without heart failure at various levels of echocardiographic (left ventricular systolic dysfunction) and clinical (symptoms) severity who were undergoing ambulatory surgery.Design, Setting, and Participants: In this US multisite retrospective cohort study of all adult patients undergoing ambulatory, elective, noncardiac surgery in the Veterans Affairs Surgical Quality Improvement Project database during fiscal years 2009 to 2016, a total of 355 121 patient records were identified and analyzed with 1 year of follow-up after surgery (final date of follow-up September 1, 2017).Exposures: Heart failure, left ventricular ejection fraction, and presence of signs or symptoms of heart failure within 30 days of surgery.Main Outcomes and Measures: The primary outcomes were postoperative mortality at 90 days and any postoperative complication at 30 days.Results: Among 355 121 total patients, outcome data from 19 353 patients with heart failure (5.5%; mean [SD] age, 67.9 [10.1] years; 18 841 [96.9%] male) and 334 768 patients without heart failure (94.5%; mean [SD] age, 57.2 [14.0] years; 301 198 [90.0%] male) were analyzed. Compared with patients without heart failure, patients with heart failure had a higher risk of 90-day postoperative mortality (crude mortality risk, 2.00% vs 0.39%; adjusted odds ratio [aOR], 1.95; 95% CI, 1.69-2.44), and risk of mortality progressively increased with decreasing systolic function. Compared with patients without heart failure, symptomatic patients with heart failure had a greater risk of mortality (crude mortality risk, 3.57%; aOR, 2.76; 95% CI, 2.07-3.70), as did asymptomatic patients with heart failure (crude mortality risk, 1.85%; aOR, 1.85; 95% CI, 1.60-2.15). Patients with heart failure had a higher risk of experiencing a 30-day postoperative complication than did patients without heart failure (crude risk, 5.65% vs 2.65%; aOR, 1.10; 95% CI, 1.02-1.19).Conclusions and Relevance: In this study, among patients undergoing elective, ambulatory surgery, heart failure with or without symptoms was significantly associated with 90-day mortality and 30-day postoperative complications. These data may be helpful in preoperative discussions with patients with heart failure undergoing ambulatory surgery.

  View details for DOI 10.1001/jamasurg.2019.2110

  View details for PubMedID 31290953

• Task Shifting in Surgery-What US Health Care Can Learn From Ghana. JAMA surgery Wren, S. M., Kushner, A. L. 2019

  View details for DOI 10.1001/jamasurg.2019.1745

  View details for PubMedID 31241737

• Health Care Providers in War and Armed Conflict: Operational and Educational Challenges in International Humanitarian Law and the Geneva Conventions, Part II. Educational and Training Initiatives DISASTER MEDICINE AND PUBLIC HEALTH PREPAREDNESS Burkle, F. M., Kushner, A. L., Giannou, C., Paterson, M. A., Wren, S. M., Burnham, G. 2019; 13 (3): 383–96

  View details for DOI 10.1017/dmp.2018.42

  View details for Web of Science ID 000476670100001

• Protecting Surgeons and Patients During Wars and Armed Conflicts: Importance of Predeployment Training on the Geneva Conventions and International Humanitarian Law. JAMA surgery Schussler, L., Burkle, F. M., Wren, S. M. 2019

  View details for DOI 10.1001/jamasurg.2019.0041

  View details for PubMedID 31141147

• Health Care Providers in War and Armed Conflict: Operational and Educational Challenges in International Humanitarian Law and the Geneva Conventions, Part I. Historical Perspective DISASTER MEDICINE AND PUBLIC HEALTH PREPAREDNESS Burkle, F. M., Kushner, A. L., Giannou, C., Paterson, M. A., Wren, S. M., Burnham, G. 2019; 13 (2): 109–15

  View details for DOI 10.1017/dmp.2018.41

  View details for Web of Science ID 000471321100005

• Delivering trauma mastery with an international trauma masters INJURY-INTERNATIONAL JOURNAL OF THE CARE OF THE INJURED Schyma, B. M., Cole, E., Wren, S. M., Brohi, K., Brundage, S. 2019; 50 (4): 877–82

  View details for DOI 10.1016/j.injury.2019.03.023

  View details for Web of Science ID 000467537800009

• Disease-free Survival and Local Recurrence for Laparoscopic Resection Compared With Open Resection of Stage II to III Rectal Cancer Follow-up Results of the ACOSOG Z6051 Randomized Controlled Trial ANNALS OF SURGERY Fleshman, J., Branda, M. E., Sargent, D. J., Boller, A., George, V. V., Abbas, M. A., Peters, W. R., Maun, D. C., Chang, G. J., Herline, A., Fichera, A., Mutch, M. G., Wexner, S. D., Whiteford, M. H., Marks, J., Birnbaum, E., Margolin, D. A., Larson, D. W., Marcello, P. W., Posner, M. C., Read, T. E., Monson, J. T., Wren, S. M., Pisters, P. T., Nelson, H. 2019; 269 (4): 589–95

  View details for DOI 10.1097/SLA.0000000000003002

  View details for Web of Science ID 000467459700017

• Association of Left Ventricular Ejection Fraction and Symptoms With Mortality After Elective Noncardiac Surgery Among Patients With Heart Failure. JAMA Lerman, B. J., Popat, R. A., Assimes, T. L., Heidenreich, P. A., Wren, S. M. 2019; 321 (6): 572-579

  Abstract

  Heart failure is an established risk factor for postoperative mortality, but how left ventricular ejection fraction and heart failure symptoms affect surgical outcomes is not fully described.To determine the risk of postoperative mortality among patients with heart failure at various levels of echocardiographic (left ventricular systolic dysfunction) and clinical (symptoms) severity compared with those without heart failure and to evaluate how risk varies across levels of surgical complexity.US multisite retrospective cohort study of all adult patients receiving elective, noncardiac surgery in the Veterans Affairs Surgical Quality Improvement Project database from 2009 through 2016. A total of 609 735 patient records were identified and analyzed with 1 year of follow-up after having surgery (final study follow-up: September 1, 2017).Heart failure, left ventricular ejection fraction, and presence of signs or symptoms of heart failure within 30 days of surgery.The primary outcome was postoperative mortality at 90 days.Outcome data from 47 997 patients with heart failure (7.9%; mean [SD] age, 68.6 [10.1] years; 1391 women [2.9%]) and 561 738 patients without heart failure (92.1%; mean [SD] age, 59.4 [13.4] years; 50 862 women [9.1%]) were analyzed. Compared with patients without heart failure, those with heart failure had a higher risk of 90-day postoperative mortality (2635 vs 6881 90-day deaths; crude mortality risk, 5.49% vs 1.22%; adjusted absolute risk difference [RD], 1.03% [95% CI, 0.91%-1.15%]; adjusted odds ratio [OR], 1.67 [95% CI, 1.57-1.76]). Compared with patients without heart failure, symptomatic patients with heart failure (n = 5906) had a higher risk (597 deaths [10.11%]; adjusted absolute RD, 2.37% [95% CI, 2.06%-2.57%]; adjusted OR, 2.37 [95% CI, 2.14-2.63]). Asymptomatic patients with heart failure (n = 42 091) (2038 deaths [crude risk, 4.84%]; adjusted absolute RD, 0.74% [95% CI, 0.63%-0.87%]; adjusted OR, 1.53 [95% CI, 1.44-1.63]), including the subset with preserved left ventricular systolic function (1144 deaths [4.42%]; adjusted absolute RD, 0.66% [95% CI, 0.54%-0.79%]; adjusted OR, 1.46 [95% CI, 1.35-1.57]), also experienced elevated risk.Among patients undergoing elective noncardiac surgery, heart failure with or without symptoms was significantly associated with 90-day postoperative mortality. These data may be helpful in preoperative discussions with patients with heart failure undergoing noncardiac surgery.

  View details for DOI 10.1001/jama.2019.0156

  View details for PubMedID 30747965

  View details for PubMedCentralID PMC6439591

• Gender and Specialty Influences on Personal and Professional Life Among Trainees ANNALS OF SURGERY Rogers, A. C., Wren, S. M., McNamara, D. A. 2019; 269 (2): 383–87

  View details for DOI 10.1097/SLA.0000000000002580

  View details for Web of Science ID 000467457600033

• High Prevalence of Adenomatous Polyps in Alaska Native People Aged 40-49 years. The Journal of surgical research Conway, A. A., Gerry, J. M., Sacco, F. n., Wren, S. M. 2019; 243: 524–30

  Abstract

  Although colorectal cancer occurs earlier in life and at twice the frequency in Alaska Native (AN) people compared with the general population, the colorectal polyp burden in this group has not been quantified. In addition, an appropriate age for initial screening in ANs has not been defined.A retrospective chart review of 766 AN people who had screening colonoscopy from 2015 to 2016 was performed. The polyp burden in patients aged 40-49 y was compared with that in those aged 50-59 y in both the AN and the general US populations.In total, 345 adenomas were removed: 121 (35%) from 40- to 49-year-olds and 224 (65%) from 50- to 59-year-olds. Twenty-six percent of AN people aged 40 y to 49 y and 40% of AN people aged 50 to 59 y had at least one adenoma. Low- and high-risk adenomas were significantly less frequent in the younger group (22% versus 29%, P = 0.048; 9.2% versus 15%, P = 0.035; respectively). Advanced adenomas were also less frequent in the younger group, although not statistically significant. Polyp histology, size, location, and morphology did not differ significantly between groups.The adenoma and advanced adenoma prevalence in 40- to 49-year-old AN people is high, suggesting colorectal cancer screening should begin at age 40 y in ANs.

  View details for DOI 10.1016/j.jss.2019.07.004

  View details for PubMedID 31377493

• Sex Disparities in Access to Surgical Care at a Single Institution in Malawi WORLD JOURNAL OF SURGERY Reid, T. D., Wren, S. M., Grudziak, J., Maine, R., Kajombo, C., Charles, A. G. 2019; 43 (1): 60–66

  Abstract

  There is a paucity of data regarding sex-based disparities in surgical care delivery, particularly in low- and middle-income countries. This study sought to determine whether sex disparities are present among patients presenting with surgical conditions in Malawi. Hypothesis compared to men, fewer women present to Kamuzu Central Hospital (KCH) with peritonitis and have longer delays in presentation for definitive care.This study performs a retrospective analysis of prospectively collected data of all general surgery patients with peritonitis presenting to KCH in Lilongwe, Malawi, from September 2013 to April 2016. Multivariable linear and logistic regressions were used to assess the effect of sex on mortality, length of stay, operative intervention, complications, and time to presentation.Of 462 patients presenting with general surgery conditions and peritonitis, 68.8% were men and 31.2% were women. After adjustments, women had significantly higher odds of non-operative management when compared to men (OR 2.17, 95%CI 1.30-3.62, P = 0.003), delays in presentation (adjusted mean difference 136 h, 95%CI 100-641, P = 0.05), delays to operation (adjusted mean difference 1.91 days, 95%CI 1.12-3.27, P = 0.02), and longer lengths of stay (adjusted mean difference 1.67 days, 95%CI 1.00-2.80, P = 0.05). There were no differences in complications or in-hospital or Emergency Department mortality.Sex disparities exist within the general surgery population at KCH in Lilongwe, Malawi. Fewer women present with surgical problems, and women experience delays in presentation, longer lengths of stay, and undergo fewer operations. Future studies to determine mortality in the community and driving factors of sex disparities will provide more insight.

  View details for PubMedID 30145674

• The Golden Hour After Injury Among Civilians Caught in Conflict Zones. Disaster medicine and public health preparedness Forrester, J. D., August, A. n., Cai, L. Z., Kushner, A. L., Wren, S. M. 2019: 1–9

  Abstract

  ABSTRACTIntroduction:The term "golden hour" describes the first 60 minutes after patients sustain injury. In resource-available settings, rapid transport to trauma centers within this time period is standard-of-care. We compared transport times of injured civilians in modern conflict zones to assess the degree to which injured civilians are transported within the golden hour in these environments.We evaluated PubMed, Ovid, and Web of Science databases for manuscripts describing transport time after trauma among civilian victims of trauma from January 1990 to November 2017.The initial database search identified 2704 abstracts. Twenty-nine studies met inclusion and exclusion criteria. Conflicts in Yugoslavia/Bosnia/Herzegovina, Syria, Afghanistan, Iraq, Israel, Cambodia, Somalia, Georgia, Lebanon, Nigeria, Democratic Republic of Congo, and Turkey were represented, describing 47 273 patients. Only 7 (24%) manuscripts described transport times under 1 hour. Transport typically required several hours to days.Anticipated transport times have important implications for field triage of injured persons in civilian conflict settings because existing overburdened civilian health care systems may become further overwhelmed if in-hospital health capacity is unable to keep pace with inflow of the severely wounded.

  View details for DOI 10.1017/dmp.2019.42

  View details for PubMedID 31203832

• A Consensus Framework for the Humanitarian Surgical Response to Armed Conflict in 21st Century Warfare. JAMA surgery Wren, S. M., Wild, H. B., Gurney, J. n., Amirtharajah, M. n., Brown, Z. W., Bulger, E. M., Burkle, F. M., Elster, E. A., Forrester, J. D., Garber, K. n., Gosselin, R. A., Groen, R. S., Hsin, G. n., Joshipura, M. n., Kushner, A. L., Norton, I. n., Osmers, I. n., Pagano, H. n., Razek, T. n., Sáenz-Terrazas, J. M., Schussler, L. n., Stewart, B. T., Traboulsi, A. A., Trelles, M. n., Troke, J. n., VanFosson, C. A., Wise, P. H. 2019

  Abstract

  Armed conflict in the 21st century poses new challenges to a humanitarian surgical response, including changing security requirements, access to patients, and communities in need, limited deployable surgical assets, resource constraints, and the requirement to address both traumatic injuries as well as emergency surgical needs of the population. At the same time, recent improvements in trauma care and systems have reduced injury-related mortality. This combination of new challenges and medical capabilities warrants reconsideration of long-standing humanitarian surgery protocols.To describe a consensus framework for surgical care designed to respond to this emerging need.An international group of 35 representatives from humanitarian agencies, US military, and academic trauma programs was invited to the Stanford Humanitarian Surgical Response in Conflict Working Group to engage in a structured process to review extant trauma protocols and make recommendations for revision.The working group's method adapted core elements of a modified Delphi process combined with consensus development conference from August 3 to August 5, 2018.Lessons from civilian and military trauma systems as well as recent battlefield experiences in humanitarian settings were integrated into a tiered continuum of response from point of injury through rehabilitation. The framework addresses the security and medical requirements as well as ethical and legal principles that guide humanitarian action. The consensus framework includes trained, lay first responders; far-forward resuscitation/stabilization centers; rapid damage control surgical access; and definitive care facilities. The system also includes nontrauma surgical care, injury prevention, quality improvement, data collection, and predeployment training requirements.Evidence suggests that modern trauma systems save lives. However, the requirements of providing this standard of care in insecure conflict settings places new burdens on humanitarian systems that must provide both emergency and trauma surgical care. This consensus framework integrates advances in trauma care and surgical systems in response to a changing security environment. It is possible to reduce disparities and improve the standard of care in these settings.

  View details for DOI 10.1001/jamasurg.2019.4547

  View details for PubMedID 31722004

• An Estimation of the Burden of Sports Injuries among African Adolescents. Journal of epidemiology and global health LeBrun, D. G., Del Rosario, J., Kelly, J. D., Wren, S. M., Spiegel, D. A., Mkandawire, N., Gosselin, R. A., Kushner, A. L. 2018; 8 (3-4): 171–75

  Abstract

  The extent to which sports injuries contribute to the burden of injury among adolescents in low- and middle-income countries (LMICs) is unknown. The goal of this study was to estimate the incidence of sports injuries among adolescents in Africa. Data from the World Health Organization Global School-Based Student Health surveys were used to estimate the annual number of African adolescents sustaining sports injuries. Gender-stratified injury rates were calculated and applied to every African country's adolescent population to estimate country-specific and continent-wide injury totals. A total of 21,858 males and 24,691 females from 14 countries were included in the analysis. Country-specific annual sports injury rates ranged from 13.5% to 38.1% in males and 5.2% to 20.2% in females. Weighted average sports injury rates for males and females were 23.7% (95% CI 23.1%-24.2%) and 12.5% (95% CI 12.1%-12.9%), respectively. When these rates were extrapolated to the adolescent populations of the African continent, an estimated 15,477,798 (95% CI 15,085,955-15,804,333) males and 7,943,625 (95% CI 7,689,429-8,197,821) females sustained sports injuries. Our findings suggest that over 23 million African adolescents sustained sports injuries annually. Further work will help to more precisely define the burden of sports injuries in LMICs and the role that surgery can play in mitigating this burden.

  View details for PubMedID 30864759

• An Estimation of the Burden of Sports Injuries among African Adolescents JOURNAL OF EPIDEMIOLOGY AND GLOBAL HEALTH LeBrun, D. G., del Rosario, J., Kelly, J. D., Wren, S. M., Spiegel, D. A., Mkandawire, N., Gosselin, R. A., Kushner, A. L. 2018; 8 (3-4): 171–75

  View details for DOI 10.2991/j.jegh.2017.10.010

  View details for Web of Science ID 000484415600011

• Impact of Left Ventricular Ejection Fraction and Active Symptoms on Perioperative Mortality in Heart Failure Patients Undergoing Elective, Noncardiac Surgery Lerman, B., Popat, R., Assimes, T., Wren, S. M. LIPPINCOTT WILLIAMS & WILKINS. 2018

  View details for Web of Science ID 000528619403363

• Global Surgery: Effective Involvement of US Academic Surgery Report of the American Surgical Association Working Group on Global Surgery Mock, C., Debas, H., Balch, C. M., Brennan, M., Buyske, J., Cusack, J., DeMeester, S., Herndon, D., Le Holterman, A., Jaffe, B., Kandil, E., Kauffman, G., Mazariegos, G., Merchant, N., Numann, P., Oleynikov, D., Olutoye, O., O'Neill, J., Shackford, S., Stock, P., Tarpley, J. L., Tuttle, T., Wolf, S., Wren, S. M., Yang, G. P. LIPPINCOTT WILLIAMS & WILKINS. 2018: 557–63

  Abstract

  : There is an unacceptably high burden of death and disability from conditions that are treatable by surgery, worldwide and especially in low- and middle-income countries (LMICs). The major actions to improve this situation need to be taken by the surgical communities, institutions, and governments of the LMICs. The US surgical community, including the US academic surgical community, has, however, important roles to play in addressing this problem. The American Surgical Association convened a Working Group to address how US academic surgery can most effectively decrease the burden from surgically treatable conditions in LMICs. The Working Group believes that the task will be most successful (1) if the epidemiologic pattern in a given country is taken into account by focusing on those surgically treatable conditions with the highest burdens; (2) if emphasis is placed on those surgical services that are most cost-effective and most feasible to scale up; and (3) if efforts are harmonized with local priorities and with existing global initiatives, such as the World Health Assembly with its 2015 resolution on essential surgery. This consensus statement gives recommendations on how to achieve those goals through the tools of academic surgery: clinical care, training and capacity building, research, and advocacy. Through all of these, the ethical principles of maximally and transparently engaging with and deferring to the interests and needs of local surgeons and their patients are of paramount importance. Notable benefits accrue to US surgeons, trainees, and institutions that engage in global surgical activities.

  View details for PubMedID 30004921

• Value of Global Surgical Activities for US Academic Health Centers: A Position Paper by the Association for Academic Surgery Global Affairs Committee, Society of University Surgeons Committee on Global Academic Surgery, and American College of Surgeons' Operation Giving Back JOURNAL OF THE AMERICAN COLLEGE OF SURGEONS Rickard, J., Onwuka, E., Joseph, S., Ozgediz, D., Krishnaswami, S., Oyetunji, T. A., Sharma, J., Ginwalla, R., Nwomeh, B. C., Jayaraman, S., Acad Global Surg Taskforce 2018; 227 (4): 455-+

  Abstract

  Academic global surgery value to low- and middle-income countries (LMICs) is increasingly understood, yet value to academic health centers (AHCs) remains unclear.A task force from the Association for Academic Surgery Global Affairs Committee and the Society for University Surgeons Committee on Global Academic Surgery designed and disseminated a survey to active US academic global surgeons. Questions included participant characteristics, global surgeon qualifications, trainee interactions, academic output, productivity challenges, and career models. The task force used the survey results to create a position paper outlining the value of academic global surgeons to AHCs.The survey had a 58% (n = 36) response rate. An academic global surgeon has a US medical school appointment, spends dedicated time in an LMIC, spends vacation time doing mission work, or works primarily in an LMIC. Most spend 1 to 3 months abroad annually, dedicating <25% effort to global surgery, including systems building, teaching, research, and clinical care. Most are university-employed and 65% report compensation is equivalent or greater than colleagues. Academic support includes administrative, protected time, funding. Most institutions do not use specific global surgery metrics to measure productivity. Barriers include funding, clinical responsibilities, and salary support.Academic global surgeons spend a modest amount of time abroad, require minimal financial support, and represent a low-cost investment in an under-recognized scholarship area. This position paper suggests measures of global surgery that could provide opportunities for AHCs and surgical departments to expand missions of service, education, and research and enhance institutional reputation while achieving societal impact.

  View details for DOI 10.1016/j.jamcollsurg.2018.07.661

  View details for Web of Science ID 000445400300008

  View details for PubMedID 30138702

• Ensuring Equity, Diversity, and Inclusion in Academic Surgery An American Surgical Association White Paper ANNALS OF SURGERY West, M. A., Hwang, S., Maier, R. V., Ahuja, N., Angelos, P., Bass, B. L., Brasel, K. J., Chen, H., Davis, K. A., Eberlein, T. J., Fong, Y., Greenberg, C. C., Lillemoe, K. D., McCarthy, M. C., Michelassi, F., Numann, P. J., Parangi, S., Reyes, J. D., Sanfey, H. A., Stain, S. C., Weigel, R. J., Wren, S. M. 2018; 268 (3): 403–7

  Abstract

  The leadership of the American Surgical Association (ASA) appointed a Task Force to objectively address issues related to equity, diversity, and inclusion with the discipline of academic surgery.Surgeons and the discipline of surgery, particularly academic surgery, have a tradition of leadership both in medicine and society. Currently, we are being challenged to harness our innate curiosity, hard work, and perseverance to address the historically significant deficiencies within our field in the areas of diversity, equity, and inclusion.The ASA leadership requested members to volunteer to serve on a Task Force to comprehensively address equity, diversity, and inclusion in academic surgery. Nine work groups reviewed the current literature, performed primary qualitative interviews, and distilled available guidelines and published primary source materials. A work product was created and published on the ASA Website and made available to the public. The full work product was summarized into this White Paper.The ASA has produced a handbook entitled: Ensuring Equity, Diversity, and Inclusion in Academic Surgery, which identifies issues and challenges, and develops a set of solutions and benchmarks to aid the academic surgical community in achieving these goals.Surgery must identify areas for improvement and work iteratively to address and correct past deficiencies. This requires honest and ongoing identification and correction of implicit and explicit biases. Increasing diversity in our departments, residencies, and universities will improve patient care, enhance productivity, augment community connections, and achieve our most fundamental ambition-doing good for our patients.

  View details for PubMedID 30004923

• Undertreated Medical Conditions vs Trauma as Primary Indications for Amputation at a Referral Hospital in Cameroon JAMA SURGERY Forrester, J. D., Teslovich, N. C., Nigo, L., Brown, J. A., Wren, S. M. 2018; 153 (9): 858–60

  View details for DOI 10.1001/jamasurg.2018.1059

  View details for Web of Science ID 000445080200020

• Where is the official guidance on Ebola and surgery? LANCET Wren, S. M., Kushner, A. L. 2018; 391 (10137): 2321–22

  View details for DOI 10.1016/S0140-6736(18)31225-X

  View details for Web of Science ID 000434643200022

• Where is the official guidance on Ebola and surgery? Lancet (London, England) Wren, S. M., Kushner, A. L. 2018

  View details for PubMedID 29858114

• What are the optimum components in a care bundle aimed at reducing post-operative pulmonary complications in high-risk patients? Perioperative medicine (London, England) Griffiths, S. V., Conway, D. H., Sander, M., Jammer, I., Grocott, M. P., Creagh-Brown, B. C. 2018; 7: 7

  Abstract

  Post-operative pulmonary complications (POPC) are common, predictable and associated with increased morbidity and mortality, independent of pre-operative risk. Interventions to reduce the incidence of POPC have been studied individually, but the use of a care bundle has not been widely investigated. The purpose of our work was to use Delphi consensus methodology and an independently chosen expert panel to formulate a care bundle for patients identified as being at high of POPC, as preparation towards an evaluation of its effectiveness at reducing POPC.We performed a survey of members of the ESICM POIC section to inform a Delphi consensus and to share their opinions on a care bundle to reduce POPC, the POPC-CB. We formed a team of 36 experts to participate in and complete an email-based Delphi consensus over three rounds, leading to the formulation of the POPC-CB.The survey had 362 respondents and informed the design of the Delphi consensus. The Delphi consensus resulted in a proposed POPC-CB that incorporates components before surgery-supervised exercise programmes and inspiratory muscle training, during surgery, low tidal volume ventilation with individualised PEEP (positive end-expiratory pressure), use of routine monitoring to avoid hyperoxia and efforts made to limit neuromuscular blockade, and post-operatively, deep breathing exercises and elevation of the head of the bed.A care bundle has been suggested for evaluation in surgical patients at high risk of POPC. Evaluation of feasibility of both implementation and effectiveness is now indicated.

  View details for DOI 10.1186/s13741-018-0084-9

  View details for PubMedID 29692886

  View details for PubMedCentralID PMC5904979

• Trends in Country-Specific Surgical Randomized Clinical Trial Publications JAMA SURGERY Forrester, J. A., Forrester, J. D., Wren, S. M. 2018; 153 (4): 386–88

  View details for DOI 10.1001/jamasurg.2017.4867

  View details for Web of Science ID 000430426600023

• Health Care Providers in War and Armed Conflict: Operational and Educational Challenges in International Humanitarian Law and the Geneva Conventions, Part II. Educational and Training Initiatives. Disaster medicine and public health preparedness Burkle, F. M., Kushner, A. L., Giannou, C. n., Paterson, M. A., Wren, S. M., Burnham, G. n. 2018: 1–14

  Abstract

  ABSTRACTNo discipline has been impacted more by war and armed conflict than health care has. Health systems and health care providers are often the first victims, suffering increasingly heinous acts that cripple the essential health delivery and public health infrastructure necessary for the protection of civilian and military victims of the state at war. This commentary argues that current instructional opportunities to prepare health care providers fall short in both content and preparation, especially in those operational skill sets necessary to manage multiple challenges, threats, and violations under international humanitarian law and to perform triage management in a resource-poor medical setting. Utilizing a historical framework, the commentary addresses the transformation of the education and training of humanitarian health professionals from the Cold War to today followed by recommendations for the future. (Disaster Med Public Health Preparedness. 2018;page 1 of 14).

  View details for PubMedID 29733000

• A Framework for a Battlefield Trauma System for Civilians. Annals of surgery Garber, K. n., Stewart, B. T., Burkle, F. M., Kushner, A. L., Wren, S. M. 2018

  View details for PubMedID 29373367

• Electricity and generator availability in LMIC hospitals: improving access to safe surgery. The Journal of surgical research Chawla, S. n., Kurani, S. n., Wren, S. M., Stewart, B. n., Burnham, G. n., Kushner, A. n., McIntyre, T. n. 2018; 223: 136–41

  Abstract

  Access to reliable energy has been identified as a global priority and codified within United Nations Sustainable Goal 7 and the Electrify Africa Act of 2015. Reliable hospital access to electricity is necessary to provide safe surgical care. The current state of electrical availability in hospitals in low- and middle-income countries (LMICs) throughout the world is not well known. This study aimed to review the surgical capacity literature and document the availability of electricity and generators.Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, a systematic search for surgical capacity assessments in LMICs in MEDLINE, PubMed, and World Health Organization Global Health Library was performed. Data regarding electricity and generator availability were extracted. Estimated percentages for individual countries were calculated.Of 76 articles identified, 21 reported electricity availability, totaling 528 hospitals. Continuous electricity availability at hospitals providing surgical care was 312/528 (59.1%). Generator availability was 309/427 (72.4%). Estimated continuous electricity availability ranged from 0% (Sierra Leone and Malawi) to 100% (Iran); estimated generator availability was 14% (Somalia) to 97.6% (Iran).Less than two-thirds of hospitals providing surgical care in 21 LMICs have a continuous electricity source or have an available generator. Efforts are needed to improve electricity infrastructure at hospitals to assure safe surgical care. Future research should look at the effect of energy availability on surgical care and patient outcomes and novel methods of powering surgical equipment.

  View details for PubMedID 29433865

• Health Care Providers in War and Armed Conflict: Operational and Educational Challenges in International Humanitarian Law and the Geneva Conventions, Part I. Historical Perspective. Disaster medicine and public health preparedness Burkle, F. M., Kushner, A. L., Giannou, C. n., Paterson, M. A., Wren, S. M., Burnham, G. n. 2018: 1–7

  Abstract

  Since 1945, the reason for humanitarian crises and the way in which the world responds to them has dramatically changed every 10 to 15 years or less. Planning, response, and recovery for these tragic events have often been ad hoc, inconsistent, and insufficient, largely because of the complexity of global humanitarian demands and their corresponding response system capabilities. This historical perspective chronicles the transformation of war and armed conflicts from the Cold War to today, emphasizing the impact these events have had on humanitarian professionals and their struggle to adapt to increasing humanitarian, operational, and political challenges. An unprecedented independent United Nations-World Health Organization decision in the Battle for Mosul in Iraq to deploy to combat zones emergency medical teams unprepared in the skills of decades-tested war and armed conflict preparation and response afforded to health care providers and dictated by International Humanitarian Law and Geneva Convention protections has abruptly challenged future decision-making and deployments. (Disaster Med Public Health Preparedness. 2018;page 1 of 7).

  View details for PubMedID 29706140

• US Military Engagement in Humanitarian Surgery What Is the Mandate? JAMA SURGERY Wren, S. M., Oh, J., Elster, E. 2017; 152 (12): 1101–2

  View details for PubMedID 28973089

• Using Epidemiology to Determine Surgical Needs in Low-Resource Settings JAMA SURGERY Forrester, J. D., Wren, S. M. 2017; 152 (12)

  View details for DOI 10.1001/jamasurg.2017.4027

  View details for Web of Science ID 000418463400003

• Curing World Blindness: The Lifeline Express Train Molera, R., Wren, S. M., Serghiou, S., Lee, S., Shields, R. A., Cho, H. ELSEVIER SCIENCE INC. 2017: S100

  View details for DOI 10.1016/j.jamcollsurg.2017.07.219

  View details for Web of Science ID 000413315300207

• Sex disparities among persons receiving operative care during armed conflicts. Surgery Forrester, J. D., Forrester, J. A., Basimouneye, J., Tahir, M., Trelles, M., Kushner, A. L., Wren, S. M. 2017

  Abstract

  Armed conflict increasingly involves civilian populations, and health care needs may be immense. We hypothesized that sex disparities may exist among persons receiving operative care in conflict zones and sought to describe predictors of disparity.We performed a retrospective analysis of operative interventions performed between 2008 and 2014 at Médecins Sans Frontières Operation Center Brussels conflict projects. A Médecins Sans Frontières Operation Center Brussels conflict project was defined as a program established in response to human conflict, war, or social unrest. Intervention- and country-level variables were evaluated. For multivariate analysis, multilevel mixed-effects logistic regression was used with random-effect modeling to account for clustering and population differences in conflict zones.Between 2008 and 2014, 49,715 interventions were performed in conflict zones by Médecins Sans Frontières Operation Center Brussels. Median patient age was 24 years (range: 1-105 years), and 34,436 (69%) were men. Patient-level variables associated with decreased interventions on women included: American Society of Anesthesiologists score (P = .003), degree of urgency (P = .02), mechanism (P < .0001), and a country's predominant religion (P = .006). Men were 1.7 times more likely to have an operative intervention in a predominantly Muslim country (P = .006).Conflict is an unfortunate consequence of humanity in a world with limited resources. For most operative interventions performed in conflict zones, men were more commonly represented. Predominant religion was the greatest predictor of increased disparity between sexes, irrespective of the number of patients presenting as a result of traumatic injury. It is critical to understand what factors may underlie this disparity to ensure equitable and appropriate care for all patients in an already tragic situation.

  View details for DOI 10.1016/j.surg.2017.03.001

  View details for PubMedID 28400124

• Applying Trauma Transfusion Practices to Nontrauma Care: A Cautionary Tale. JAMA surgery Rinderknecht, T. N., Wren, S. M. 2017

  View details for DOI 10.1001/jamasurg.2017.0091

  View details for PubMedID 28273302

• Reasons for faculty departures from an academic medical center: a survey and comparison across faculty lines BMC MEDICAL EDUCATION Girod, S. C., Fassiotto, M., Menorca, R., Etzkowitz, H., Wren, S. M. 2017; 17

  Abstract

  Faculty departure can present significant intellectual costs to an institution. The authors sought to identify the reasons for clinical and non-clinical faculty departures at one academic medical center (AMC).In May and June 2010, the authors surveyed 137 faculty members who left a west coast School of Medicine (SOM) between 1999 and 2009. In May and June 2015, the same survey was sent to 40 faculty members who left the SOM between 2010-2014, for a total sample size of 177 former faculty members. The survey probed work history and experience, reasons for departure, and satisfaction at the SOM versus their current workplace. Statistical analyses included Pearson's chi-square test of independence and independent sample t-tests to understand quantitative differences between clinical and non-clinical respondents, as well as coding of qualitative open-ended responses.Eighty-eight faculty members responded (50%), including three who had since returned to the SOM. Overall, professional and advancement opportunities, salary concerns, and personal/family reasons were the three most cited factors for leaving. The average length of time at this SOM was shorter for faculty in clinical roles, who expressed lower workplace satisfaction and were more likely to perceive incongruence and inaccuracy in institutional expectations for their success than those in non-clinical roles. Clinical faculty respondents noted difficulty in balancing competing demands and navigating institutional expectations for advancement as reasons for leaving.AMCs may not be meeting faculty needs, especially those in clinical roles who balance multiple missions as clinicians, researchers, and educators. Institutions should address the challenges these faculty face in order to best recruit, retain, and advance faculty.

  View details for DOI 10.1186/s12909-016-0830-y

  View details for PubMedID 28073345

• Meta-analysis of individual-patient data from EVAR-1, DREAM, OVER and ACE trials comparing outcomes of endovascular or open repair for abdominal aortic aneurysm over 5 years. The British journal of surgery Powell, J. T., Sweeting, M. J., Ulug, P. n., Blankensteijn, J. D., Lederle, F. A., Becquemin, J. P., Greenhalgh, R. M. 2017; 104 (3): 166–78

  Abstract

  The erosion of the early mortality advantage of elective endovascular aneurysm repair (EVAR) compared with open repair of abdominal aortic aneurysm remains without a satisfactory explanation.An individual-patient data meta-analysis of four multicentre randomized trials of EVAR versus open repair was conducted to a prespecified analysis plan, reporting on mortality, aneurysm-related mortality and reintervention.The analysis included 2783 patients, with 14 245 person-years of follow-up (median 5·5 years). Early (0-6 months after randomization) mortality was lower in the EVAR groups (46 of 1393 versus 73 of 1390 deaths; pooled hazard ratio 0·61, 95 per cent c.i. 0·42 to 0·89; P = 0·010), primarily because 30-day operative mortality was lower in the EVAR groups (16 deaths versus 40 for open repair; pooled odds ratio 0·40, 95 per cent c.i. 0·22 to 0·74). Later (within 3 years) the survival curves converged, remaining converged to 8 years. Beyond 3 years, aneurysm-related mortality was significantly higher in the EVAR groups (19 deaths versus 3 for open repair; pooled hazard ratio 5·16, 1·49 to 17·89; P = 0·010). Patients with moderate renal dysfunction or previous coronary artery disease had no early survival advantage under EVAR. Those with peripheral artery disease had lower mortality under open repair (39 deaths versus 62 for EVAR; P = 0·022) in the period from 6 months to 4 years after randomization.The early survival advantage in the EVAR group, and its subsequent erosion, were confirmed. Over 5 years, patients of marginal fitness had no early survival advantage from EVAR compared with open repair. Aneurysm-related mortality and patients with low ankle : brachial pressure index contributed to the erosion of the early survival advantage for the EVAR group. Trial registration numbers: EVAR-1, ISRCTN55703451; DREAM (Dutch Randomized Endovascular Aneurysm Management), NCT00421330; ACE (Anévrysme de l'aorte abdominale, Chirurgie versus Endoprothèse), NCT00224718; OVER (Open Versus Endovascular Repair Trial for Abdominal Aortic Aneurysms), NCT00094575.

  View details for DOI 10.1002/bjs.10430

  View details for PubMedID 28160528

• Training in Divergent and Convergent Force Fields During 6-DOF Teleoperation with a Robot-Assisted Surgical System Coad, M. M., Okamura, A. M., Wren, S., Mintz, Y., Lendvay, T. S., Jarc, A. M., Nisky, I., Gerling, G., Otaduy, M. A., Ryu, J. H. IEEE. 2017: 195–200

  View details for Web of Science ID 000426705900034

• Clostridium difficile infection in Low- and Middle-Human Development Index Countries: A systematic review. Tropical medicine & international health : TM & IH Forrester, J. D., Cai, L. Z., Mbanje, C. n., Rinderknecht, T. N., Wren, S. M. 2017

  Abstract

  To describe the impact and epidemiology of Clostridium difficile (C.difficile) infection (CDI) in low- and middle-human development index (LMHDI) countries.Prospectively registered, systematic literature review of existing literature in the PubMed, Ovid, and Web of Science databases describing the epidemiology and management of C.difficile in LMHDI countries. Risk factors were compared between studies when available.Of the 218 abstracts identified after applying search criteria, 25 studies were reviewed in detail. The weighted pooled infection rate among symptomatic non-immunosuppressed inpatients was 15.8% (95% CI 12.1%-19.5%) and was 10.1% (95% CI 3.0%-17.2%) among symptomatic outpatients. Subgroup analysis of immunosuppressed patient populations revealed pooled infection rates similar to non-immunosuppressed patient populations. Risk factor analysis was infrequently performed.While the percentages of patients with CDI in LMHDI countries among the reviewed studies are lower than expected, there remains a paucity of epidemiologic data evaluating burden of C. difficile infection in these settings. This article is protected by copyright. All rights reserved.

  View details for PubMedID 28796388

• Trends in Country-Specific Surgical Randomized Clinical Trial Publications. JAMA surgery Forrester, J. A., Forrester, J. D., Wren, S. M. 2017

  View details for PubMedID 29282466

• Sex Differences in Civilian Injury in Baghdad From 2003 to 2014: Results of a Randomized Household Cluster Survey. Annals of surgery Shaak, K. n., Lafta, R. n., Stewart, B. T., Fowler, T. R., Al-Shatari, S. A., Burnham, G. n., Cherewick, M. n., Wren, S. M., Groen, R. S., Kushner, A. L. 2017

  Abstract

  To examine sex differences in injury mechanisms, injury-related death, injury-related disability, and associated financial consequences in Baghdad since the 2003 invasion of Iraq to inform prevention initiatives, health policy, and relief planning.Reliable estimates of injury burden among civilians during conflict are lacking, particularly among vulnerable subpopulations, such as women.A 2-stage, cluster randomized, community-based household survey was conducted in May 2014 to determine the civilian burden of injury in Baghdad since 2003. Households were surveyed regarding injury mechanisms, healthcare required, disability, deaths, connection to conflict, and resultant financial hardship.We surveyed 900 households (5148 individuals), reporting 553 injuries, 162 (29%) of which were injuries among women. The mean age of injury was higher among women compared with men (34 ± 21.3 vs 27 ± 16.5 years; P < 0.001). More women than men were injured while in the home [104 (64%) vs 82 (21%); P < 0.001]. Fewer women than men died from injuries [11 (6.8%) vs 77 (20%); P < 0.001]; however, women were more likely than men to live with reduced function [101 (63%) vs 192 (49%); P = 0.005]. Of intentional injuries, women had higher rates of injury by shell fragments (41% vs 26%); more men were injured by gunshots [76 (41%) vs 6 (17.6%); P = .011).Women experienced fewer injuries than men in postinvasion Baghdad, but were more likely to suffer disability after injury. Efforts to improve conditions for injured women should focus on mitigating financial and provisional hardships, providing counseling services, and ensuring access to rehabilitation services.

  View details for DOI 10.1097/SLA.0000000000002140

  View details for PubMedID 28151803

• Consensus recommendations for essential vascular care in low- and middle-income countries JOURNAL OF VASCULAR SURGERY Stewart, B. T., Gyedu, A., Giannou, C., Mishra, B., Rich, N., Wren, S. M., Mock, C., Kushner, A. L. 2016; 64 (6): 1770-?

  Abstract

  Many low- and middle-income countries (LMICs) are ill equipped to care for the large and growing burden of vascular conditions. We aimed to develop essential vascular care recommendations that would be feasible for implementation at nearly every setting worldwide, regardless of national income.The normative Delphi method was used to achieve consensus on essential vascular care resources among 27 experts in multiple areas of vascular care and public health as well as with experience in LMIC health care. Five anonymous, iterative rounds of survey with controlled feedback and a statistical response were used to reach consensus on essential vascular care resources.The matrices provide recommendations for 92 vascular care resources at each of the four levels of care in most LMICs, comprising primary health centers and first-level, referral, and tertiary hospitals. The recommendations include essential and desirable resources and encompass the following categories: screening, counseling, and evaluation; diagnostics; medical care; surgical care; equipment and supplies; and medications.The resources recommended have the potential to improve the ability of LMIC health care systems to respond to the large and growing burden of vascular conditions. Many of these resources can be provided with thoughtful planning and organization, without significant increases in cost. However, the resources must be incorporated into a framework that includes surveillance of vascular conditions, monitoring and evaluation of vascular capacity and care, a well functioning prehospital and interhospital transport system, and vascular training for existing and future health care providers.

  View details for DOI 10.1016/j.jvs.2016.05.046

  View details for PubMedID 27432199

• Long-term Cost-effectiveness in the Veterans Affairs Open vs Endovascular Repair Study of Aortic Abdominal Aneurysm A Randomized Clinical Trial JAMA SURGERY Lederle, F. A., Stroupe, K. T., Kyriakides, T. C., Ge, L., Freischlag, J. A., Open Vs Endovascular Repair OVER V 2016; 151 (12): 1139-1144

  Abstract

  Because of the similarity in clinical outcomes after elective open and endovascular repair of abdominal aortic aneurysm (AAA), cost may be an important factor in choosing a procedure.To compare total and AAA-related use of health care services, costs, and cost-effectiveness between groups randomized to open or endovascular repair.This unblinded randomized clinical trial enrolled 881 patients undergoing planned elective repair of AAA who were candidates for open and endovascular repair procedures. Patients were randomized from October 15, 2002, to April 15, 2008, at 42 Veterans Affairs medical centers. Follow-up was completed on October 15, 2011, and data were analyzed from April 15, 2013, to April 15, 2016, based on intention to treat.Mean total and AAA-related health care cost per life-year and per quality-adjusted life-year (QALY).A total of 881 patients (876 men [99.4%]; 5 women [0.6%]; mean [SD] age, 70 [7.8] years) were included in the analysis. After a mean of 5.2 years of follow-up, mean life-years were 4.89 in the endovascular group and 4.84 in the open repair group (P = .68), and mean QALYs were 3.72 in the endovascular group and 3.70 in the open repair group (P = .82). Total mean health care costs did not differ significantly between the 2 groups (endovascular group, $142 745; open repair group, $153 533; difference, -$10 788; 95% CI, -$29 796 to $5825; P = .25). Costs related to AAA, including the initial repair, constituted nearly 40% of total costs and did not differ significantly between the 2 groups (endovascular group, $57 501; open repair group, $57 893; difference, -$393; 95% CI, -$12 071 to $7928; P = .94). Lower costs due to shorter hospitalization for initial endovascular repair were offset by increased costs from AAA-related secondary procedures and imaging studies. The probability of endovascular repair being less costly and more effective was 56.8% when effectiveness was measured in life-years and 55.4% when effectiveness was measured in QALYs for total costs and 31.3% and 34.3%, respectively, for AAA-related costs.In this multicenter randomized clinical trial with follow-up to 9 years, survival, quality of life, costs, and cost-effectiveness did not differ between elective open and endovascular repair of AAA.clinicaltrials.gov Identifier: NCT00094575.

  View details for DOI 10.1001/jamasurg.2016.2783

  View details for Web of Science ID 000391556100011

  View details for PubMedID 27627802

• Beyond Infrastructure: Understanding Why Patients Decline Surgery in the Developing World: An Observational Study in Cameroon. Annals of surgery Lerman, B. J., Alsan, M., Chia, N. J., Brown, J. A., Wren, S. M. 2016: -?

  Abstract

  The aim of this study was to quantify and describe a population of patients in rural Cameroon who present with a surgically treatable illness but ultimately decline surgery, and to understand the patient decision-making process and identify key socioeconomic factors that result in barriers to care.An estimated 5 billion people lack access to safe, affordable surgical care and anesthesia when needed, and this unmet need resides disproportionally in low-income countries (LICs). An understanding of the socioeconomic factors underlying decision-making is key to future efforts to expand surgical care delivery in this population. We assessed patient decision-making in a LIC with a cash-based health care economy.Standardized interviews were conducted of a random sample of adult patients with treatable surgical conditions over a 7-week period in a tertiary referral hospital in rural Cameroon. Main outcome measures included participant's decision to accept or decline surgery, source of funding, and the relative importance of various factors in the decision-making process.Thirty-four of 175 participants (19.4%) declined surgery recommended by their physician. Twenty-six of 34 participants declining surgery (76.4%) cited procedure cost, which on average equaled 6.4 months' income, as their primary decision factor. Multivariate analysis revealed female gender [odds ratio (OR) 3.35, 95% confidence interval (95% CI) 2.14-5.25], monthly earnings (OR 0.83, 95% CI, 0.77-0.89), supporting children in school (OR 1.22, 95% CI 1.13-1.31), and inability to borrow funds from family or the community (OR 6.49, 95% CI 4.10-10.28) as factors associated with declining surgery.Nearly one-fifth of patients presenting to a surgical clinic with a treatable condition did not ultimately receive needed surgery. Both financial and sociocultural factors contribute to the decision to decline care.

  View details for PubMedID 27849672

• Enhancing Local Resources in Low- and Middle-Income Countries Through Education. JAMA surgery Yang, G. P., Wren, S. M. 2016

  View details for DOI 10.1001/jamasurg.2016.3365

  View details for PubMedID 27706484

• Geographic Variation in Surgical Outcomes and Cost Between the United States and Japan AMERICAN JOURNAL OF MANAGED CARE Hurley, M. P., Schoemaker, L., Morton, J. M., Wren, S. M., Vogt, W. B., Watanabe, S., Yoshikawa, A., Bhattacharya, J. 2016; 22 (9): 600-?

  Abstract

  Unwarranted geographic variation in spending has received intense scrutiny in the United States. However, few studies have compared variation in spending and surgical outcomes between the United States healthcare system and those of other nations. In this study, we compare the geographic variation in postsurgical outcomes and cost between the United States and Japan.This retrospective cohort study uses Medicare Part A data from the United States (2010-2011) and similar inpatient data from Japan (2012). Patients 65 years or older undergoing 1 of 5 surgeries (coronary artery bypass graft, abdominal aortic aneurysm repair, colectomy, pancreatectomy, or gastrectomy) were selected in the United States and Japan.Reliability- and case-mix-adjusted coefficient of variation (COV) values were calculated using hierarchical modeling and empirical Bayes techniques for the following 5 outcomes: postoperative mortality, the development of a complication, death after complication (failure to rescue), length of stay, and the cost of the hospitalization. Sensitivity analyses were also performed by calculating patient demographic-and case-mix-adjusted COV values for each outcome using weighted age- and sex-standardized values.The variability of the postsurgical outcomes was uniformly lower in the United States compared with Japan. Cost variation was consistently higher in the United States for all surgeries.Although the US healthcare system may be more inefficient regarding costs, the presence of higher geographic variation in postoperative care in Japan, relative to the United States, suggests that the observed geographic variation in the United States-both for health expenditures and outcomes-is not a unique manifestation of its structural shortcomings.

  View details for Web of Science ID 000384740300009

  View details for PubMedID 27662222

• Urgent and Elective Robotic Single-Site Cholecystectomy: Analysis and Learning Curve of 150 Consecutive Cases JOURNAL OF LAPAROENDOSCOPIC & ADVANCED SURGICAL TECHNIQUES Kubat, E., Hansen, N., Nguyen, H., Wren, S. M., Eisenberg, D. 2016; 26 (3): 185-191

  Abstract

  The use of robotic single-site cholecystectomy has increased exponentially. There are few reports describing the safety, efficacy, and operative learning curve of robotic single-site cholecystectomy either in the community setting or with nonelective surgery.We performed a retrospective review of a prospective database of our initial experience with robotic single-site cholecystectomy. Demographics and perioperative outcomes were evaluated for both urgent and elective cholecystectomy. Cumulative sum analysis was performed to determine the surgeon's learning curve.One hundred fifty patients underwent robotic single-site cholecystectomy. Seventy-four (49.3%) patients underwent urgent robotic single-site cholecystectomy, and 76 (50.7%) underwent elective robotic single-site cholecystectomy. Mean total operative time for robotic single-site cholecystectomy was 83.3 ± 2.7 minutes. Mean operative time for the urgent cohort was significantly longer than for the elective cohort (95.0 ± 4.4 versus 71.9 ± 2.6 minutes; P < .001). There was one conversion in the urgent cohort and none in the elective cohort. There was one bile duct injury (0.7%) in the urgent cohort. Perioperative complications occurred in 8.7% of patients, and most consisted of superficial surgical-site infections. There were no incisional hernias detected. The surgeon's learning curve, inclusive of urgent and elective cases, was 48 operations.Robotic single-site cholecystectomy can be performed safely and effectively in both elective and urgent cholecystectomy with a reasonable learning curve and acceptable perioperative outcomes.

  View details for DOI 10.1089/lap.2015.0528

  View details for Web of Science ID 000372455000005

• Self-reported Determinants of Access to Surgical Care in 3 Developing Countries JAMA SURGERY Forrester, J. D., Forrester, J. A., Kamara, T. B., Groen, R. S., Shrestha, S., Gupta, S., Kyamanywa, P., Petroze, R. T., Kushner, A. L., Wren, S. M. 2016; 151 (3): 257-263

  Abstract

  Surgical care is recognized as a growing component of global public health.To assess self-reported barriers to access of surgical care in Sierra Leone, Rwanda, and Nepal using the validated Surgeons OverSeas Assessment of Surgical Need tool.Data for this cross-sectional, cluster-based population survey were collected from households in Rwanda (October 2011), Sierra Leone (January 2012), and Nepal (May and June 2014) using the Surgeons OverSeas Assessment of Surgical Need tool.Basic demographic information, cost and mode of transportation to health care facilities, and barriers to access to surgical care of persons dying within the past year were analyzed.A total of 4822 households were surveyed in Nepal, Rwanda, and Sierra Leone. Primary health care facilities were commonly reached rapidly by foot (>70%), transportation to secondary facilities differed by country, and public transportation was ubiquitously required for access to a tertiary care facility (46%-82% of respondents). Reasons for not seeking surgical care when needed included no money for health care (Sierra Leone: n = 103; 55%), a person dying before health care could be arranged (all countries: 32%-43%), no health care facility available (Nepal: n = 11; 42%), and a lack of trust in health care (Rwanda: n = 6; 26%).Self-reported determinants of access to surgical care vary widely among Sierra Leone, Rwanda, and Nepal, although commonalities exist. Understanding the epidemiology of barriers to surgical care is essential to effectively provide surgical service as a public health commodity in developing countries.

  View details for DOI 10.1001/jamasurg.2015.3431

  View details for Web of Science ID 000372286200014

• Process improvement in surgery CURRENT PROBLEMS IN SURGERY Minami, C. A., Sheils, C. R., Bilimoria, K. Y., Johnson, J. K., Berger, E. R., Berian, J. R., Englesbe, M. J., Guillamondegui, O. D., Hines, L. H., Cofer, J. B., Flum, D. R., Thiriby, R. C., Kazaure, H. S., Wren, S. M., O'Leary, K. J., Thurk, J. L., Kennedy, G. D., Tevis, S. E., Yang, A. D. 2016; 53 (2): 62-96

  View details for DOI 10.1067/j.cpsurg.2015.11.001

  View details for PubMedID 26806271

• Missing the obvious: psychosocial obstacles in Veterans with hepatocellular carcinoma HPB Hwa, K. J., Dua, M. M., Wren, S. M., Visser, B. C. 2015; 17 (12): 1124-1129

  Abstract

  Socioeconomic disparities in patients with hepatocellular carcinoma (HCC) influence medical treatment. In addition to socioeconomic barriers, the Veteran population suffers from significant psychosocial obstacles. This study identifies the social challenges that Veterans face while undergoing treatment for HCC.One hundred Veterans at the Palo Alto VA treated for HCC from 2009 to 2014 (50 consecutive patients who underwent a surgical procedure; 50 treated with intra-arterial therapy) were retrospectively reviewed.Substance abuse history was identified in 96%, and half were unemployed. Most patients survived on a limited income [median $1340, interquartile range (IQR) 900-2125]; 36% on ≤ $1000/month, 37% between $1001-2000/month and 27% with >$2000/month. A history of homelessness was found in 30%, more common in those of the lowest income (57% of ≤$1K/month group, 23% of $1-2K/month group and 9% of >$2K/month group, P < 0.01). Psychiatric illness was present in 64/100 patients; among these the majority received ongoing psychiatric treatment. Transportation was provided to 23% of patients who would otherwise have been unable to attend medical appointments.Psychiatric disease and substance abuse are highly prevalent among Veterans with HCC. Most patients survive on a very meager income. These profound socioeconomic and psychosocial problems must be recognized when providing care for HCC to this population to provide adequate treatment and surveillance.

  View details for DOI 10.1111/hpb.12508

  View details for Web of Science ID 000368291100010

• Infant, maternal, and geographic factors influencing gastroschisis related mortality in Zimbabwe SURGERY Apfeld, J. C., Wren, S. M., Macheka, N., Mbuwayesango, B. A., Bruzoni, M., Sylvester, K. G., Kastenberg, Z. J. 2015; 158 (6): 1476-1481

  Abstract

  Survival for infants with gastroschisis in developed countries has improved dramatically in recent decades with reported mortality rates of 4-7%. Conversely, mortality rates for gastroschisis in sub-Saharan Africa remain as great as 60% in contemporary series. This study describes the burden of gastroschisis at the major pediatric hospital in Zimbabwe with the goal of identifying modifiable factors influencing gastroschisis-related infant mortality.We performed a retrospective cohort study of all cases of gastroschisis admitted to Harare Children's Hospital in 2013. Univariate and multivariate analyses were performed to describe infant, maternal, and geographic factors influencing survival.A total of 5,585 neonatal unit admissions were identified including 95 (1.7%) infants born with gastroschisis. Gastroschisis-related mortality was 84% (n = 80). Of infants with gastroschisis, 96% (n = 91) were born outside Harare Hospital, 82% (n = 78) were born outside Harare Province, and 23% (n = 25) were home births. The unadjusted odds of survival for these neonates with gastroschisis were decreased for low birth weight infants (<2,500 grams; odds ratio [OR], 0.15; 95% CI, 0.05-0.51), preterm births (<37 weeks gestational age; OR, 0.06; 95% CI, 0.01-0.50), and for those born to teenage mothers (<20 years of age; OR, 0.05; 95% CI, 0.01-0.46). There was also a trend toward decreased odds of survival for home births (OR, 0.16; 95% CI, 0.02-1.34) and for those born outside Harare Province (OR, 0.35; 95% CI, 0.10-1.22).Gastroschisis-related infant mortality in Zimbabwe is associated with well-known risk factors, including low birth weight, prematurity, and teenage mothers. However, modifiable factors identified in this study signify potential opportunities for developing innovative approaches to perinatal care in such a resource-constrained environment.

  View details for DOI 10.1016/j.surg.2015.04.037

  View details for Web of Science ID 000364612200004

• Effect of Laparoscopic-Assisted Resection vs Open Resection of Stage II or III Rectal Cancer on Pathologic Outcomes The ACOSOG Z6051 Randomized Clinical Trial JAMA-JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION Fleshman, J., Branda, M., Sargent, D. J., Boller, A. M., George, V., Abbas, M., Peters, W. R., Maun, D., Chang, G., Herline, A., Fichera, A., Mutch, M., Wexner, S., Whiteford, M., Marks, J., Birnbaum, E., Margolin, D., Larson, D., Marcello, P., Posner, M., Read, T., Monson, J., Wren, S. M., Pisters, P. W., Nelson, H. 2015; 314 (13): 1346-1355

  Abstract

  Evidence about the efficacy of laparoscopic resection of rectal cancer is incomplete, particularly for patients with more advanced-stage disease.To determine whether laparoscopic resection is noninferior to open resection, as determined by gross pathologic and histologic evaluation of the resected proctectomy specimen.A multicenter, balanced, noninferiority, randomized trial enrolled patients between October 2008 and September 2013. The trial was conducted by credentialed surgeons from 35 institutions in the United States and Canada. A total of 486 patients with clinical stage II or III rectal cancer within 12 cm of the anal verge were randomized after completion of neoadjuvant therapy to laparoscopic or open resection.Standard laparoscopic and open approaches were performed by the credentialed surgeons.The primary outcome assessing efficacy was a composite of circumferential radial margin greater than 1 mm, distal margin without tumor, and completeness of total mesorectal excision. A 6% noninferiority margin was chosen according to clinical relevance estimation.Two hundred forty patients with laparoscopic resection and 222 with open resection were evaluable for analysis of the 486 enrolled. Successful resection occurred in 81.7% of laparoscopic resection cases (95% CI, 76.8%-86.6%) and 86.9% of open resection cases (95% CI, 82.5%-91.4%) and did not support noninferiority (difference, -5.3%; 1-sided 95% CI, -10.8% to ∞; P for noninferiority = .41). Patients underwent low anterior resection (76.7%) or abdominoperineal resection (23.3%). Conversion to open resection occurred in 11.3% of patients. Operative time was significantly longer for laparoscopic resection (mean, 266.2 vs 220.6 minutes; mean difference, 45.5 minutes; 95% CI, 27.7-63.4; P < .001). Length of stay (7.3 vs 7.0 days; mean difference, 0.3 days; 95% CI, -0.6 to 1.1), readmission within 30 days (3.3% vs 4.1%; difference, -0.7%; 95% CI, -4.2% to 2.7%), and severe complications (22.5% vs 22.1%; difference, 0.4%; 95% CI, -4.2% to 2.7%) did not differ significantly. Quality of the total mesorectal excision specimen in 462 operated and analyzed surgeries was complete (77%) and nearly complete (16.5%) in 93.5% of the cases. Negative circumferential radial margin was observed in 90% of the overall group (87.9% laparoscopic resection and 92.3% open resection; P = .11). Distal margin result was negative in more than 98% of patients irrespective of type of surgery (P = .91).Among patients with stage II or III rectal cancer, the use of laparoscopic resection compared with open resection failed to meet the criterion for noninferiority for pathologic outcomes. Pending clinical oncologic outcomes, the findings do not support the use of laparoscopic resection in these patients.clinicaltrials.gov Identifier: NCT00726622.

  View details for DOI 10.1001/jama.2015.10529

  View details for PubMedID 26441179

• Analysis of a Hospital-Based Trauma Registry in Rural Cameroon: Description of Initial Results and Recommendations Esquivel, M. M., Long, C., Kaggya, K. M., Uribe-Leitz, T., Weiser, T. G., Wren, S. M. ELSEVIER SCIENCE INC. 2015: S86–S87

  View details for DOI 10.1016/j.jamcollsurg.2015.07.196

  View details for Web of Science ID 000361119700168

• Factors associated with delays to surgical presentation in North-West Cameroon SURGERY Long, C., Tagang, E. T., Popat, R. A., Lawong, E. K., Brown, J. A., Wren, S. M. 2015; 158 (3): 756-763

  Abstract

  Few studies have examined critically the delays in definitive management for surgical diseases in Sub-Saharan Africa. This study investigates factors contributing to delays at Mbingo Baptist Hospital, a tertiary referral hospital in Cameroon.During a 6-week period, we randomly interviewed 220 patients (39.2%) admitted to the surgical or orthopedic service and/or their caregivers. All patients >age 15 years admitted with a diagnosis of cancer or urgent operative condition (defined as requiring a definitive operation within 48 hours of admission) including trauma were interviewed. Delay was defined as receiving treatment >7 days after symptoms appeared in the urgent cohort and >1 month for the cancer cohort.In the urgent cohort, 60.3% patients had delays >7 days to hospital presentation. Compared with nondelayed patients, delayed patients were more likely to have sought care >1 day after symptoms appeared (45.4% vs 6.3%, P < .0001) and to have received previous medical care (92.8% vs 73.4%, P = .0007). Of all patients who received previous care, those with delays, compared those with no delays, visited ≥2 other providers (50.5% vs 18.8%, P < .0001), received a surgical procedure at previous episode(s) of care (21.1% vs 6.4%, P = .026), and felt no improvement after this care (80.4% vs 61.0%, P = .003). In the cancer cohort, 100% experienced >1 month delay. 100% had received medical care prior to arriving at Mbingo Baptist Hospital, 81.4% sought care from at least 3 different facilities, and none believed this care addressed their health concerns.Significant delays most often were caused by time spent on previous failed attempts at care. This information can be used to inform policy discussions about optimal health care organization within the country.

  View details for DOI 10.1016/j.surg.2015.04.016

  View details for PubMedID 26067462

• Global opportunities on 239 general surgery residency Web sites. The Journal of surgical research Wackerbarth, J. J., Campbell, T. D., Wren, S., Price, R. R., Maier, R. V., Numann, P., Kushner, A. L. 2015; 198 (1): 115-9

  Abstract

  Many general surgical residency programs lack a formal international component. We hypothesized that most surgery programs do not have international training or do not provide the information to prospective applicants regarding electives or programs in an easily accessible manner via Web-based resources.Individual general surgery program Web sites and the American College of Surgeons residency tool were used to identify 239 residencies. The homepages were examined for specific mention of international or global health programs. Ease of access was also considered. Global surgery specific pages or centers were noted. Programs were assessed for length of rotation, presence of research component, and mention of benefits to residents and respective institution.Of 239 programs, 24 (10%) mentioned international experiences on their home page and 42 (18%) contained information about global surgery. Of those with information available, 69% were easily accessible. Academic programs were more likely than independent programs to have information about international opportunities on their home page (13.7% versus 4.0%, P = 0.006) and more likely to have a dedicated program or pathway Web site (18.8% versus 2.0%, P < 0.0001). Half of the residencies with global surgery information did not have length of rotation available. Research was only mentioned by 29% of the Web sites. Benefits to high-income country residents were discussed more than benefits to low- and middle-income country residents (57% versus 17%).General surgery residency programs do not effectively communicate international opportunities for prospective residents through Web-based resources and should seriously consider integrating international options into their curriculum and better present them on department Web sites.

  View details for DOI 10.1016/j.jss.2015.05.023

  View details for PubMedID 26055214

• Global opportunities on 239 general surgery residency Web sites JOURNAL OF SURGICAL RESEARCH Wackerbarth, J. J., Campbell, T. D., Wren, S., Price, R. R., Maier, R. V., Numann, P., Kushner, A. L. 2015; 198 (1): 115-119

  Abstract

  Many general surgical residency programs lack a formal international component. We hypothesized that most surgery programs do not have international training or do not provide the information to prospective applicants regarding electives or programs in an easily accessible manner via Web-based resources.Individual general surgery program Web sites and the American College of Surgeons residency tool were used to identify 239 residencies. The homepages were examined for specific mention of international or global health programs. Ease of access was also considered. Global surgery specific pages or centers were noted. Programs were assessed for length of rotation, presence of research component, and mention of benefits to residents and respective institution.Of 239 programs, 24 (10%) mentioned international experiences on their home page and 42 (18%) contained information about global surgery. Of those with information available, 69% were easily accessible. Academic programs were more likely than independent programs to have information about international opportunities on their home page (13.7% versus 4.0%, P = 0.006) and more likely to have a dedicated program or pathway Web site (18.8% versus 2.0%, P < 0.0001). Half of the residencies with global surgery information did not have length of rotation available. Research was only mentioned by 29% of the Web sites. Benefits to high-income country residents were discussed more than benefits to low- and middle-income country residents (57% versus 17%).General surgery residency programs do not effectively communicate international opportunities for prospective residents through Web-based resources and should seriously consider integrating international options into their curriculum and better present them on department Web sites.

  View details for DOI 10.1016/j.jss.2015.05.023

  View details for Web of Science ID 000360707300019

• Promoting quality of care in disaster response: A survey of core surgical competencies SURGERY Wong, E. G., Razek, T., Elsharkawi, H., Wren, S. M., Kushner, A. L., Giannou, C., Khwaja, K. A., Beckett, A., Deckelbaum, D. L. 2015; 158 (1): 78-84

  Abstract

  Recent humanitarian crises have led to a call for professionalization of the humanitarian field, but core competencies for the delivery of surgical care have yet to be established. The objective of this study was to survey surgeons with experience in disaster response to identify surgical competencies required to be effective in these settings.An online survey elucidating demographic information, scope of practice, and previous experience in global health and disaster response was transmitted to surgeons from a variety of surgical societies and nongovernmental organizations. Participants were provided with a list of 111 operative procedures and were asked to identify those deemed essential to the toolset of a frontline surgeon in disaster response via a Likert scale. Responses from personnel with experience in disaster response were contrasted with those from nonexperienced participants.A total of 147 surgeons completed the survey. Participants held citizenship in 22 countries, were licensed in 30 countries, and practiced in >20 countries. Most respondents (56%) had previous experience in humanitarian response. The majority agreed or strongly agreed that formal training (54%), past humanitarian response (94%), and past global health experiences (80%) provided adequate preparation. The most commonly deemed important procedures included control of intraabdominal hemorrhage (99%), abdominal packing for trauma (99%), and wound debridement (99%). Procedures deemed important by experienced personnel spanned multiple specialties.This study addressed specifically surgical competencies in disaster response. We provide a list of operative procedures that should set the stage for further structured education programs.

  View details for DOI 10.1016/j.surg.2015.02.011

  View details for PubMedID 25843337

• Recommendations for including surgery on the public health agenda JOURNAL OF SURGICAL RESEARCH Wong, E. G., Ameh, E. A., Wren, S. M., Mulwafu, W., Hardy, M. A., Nwomeh, B. C., Kushner, A. L., Price, R. R. 2015; 197 (1): 112-117

  Abstract

  Surgical care has made limited inroads on the public health and global health agendas despite increasing data showing the enormous need. The objective of this study was to survey interested members of a global surgery community to identify patterns of thought regarding barriers to political priority.All active members of the nongovernmental organization Surgeons OverSeas were surveyed and asked why surgical care is not receiving recognition and support on the public health and global health agenda. Responses were categorized using the Shiffman framework on determinants of political priority for global initiatives by two independent investigators, and the number of responses for each of the 11 factors was calculated.Seventy-five Surgeons OverSeas members replied (75 of 176; 42.6% response rate). A total of 248 individual reasons were collected. The most common responses were related to external frame, defined as public portrayals of the issue (60 of 248; 24.2%), and lack of effective interventions (48 of 248; 19.4%). Least cited reasons related to global governance structure (4 of 248; 2.4%) and policy window (4 of 248; 1.6%).This survey of a global surgery community identified a number of barriers to the recognition of surgical care on the global health agenda. Recommendations include improving the public portrayal of the problem; developing effective interventions and seeking strong and charismatic leadership.

  View details for DOI 10.1016/j.jss.2015.04.020

  View details for PubMedID 25940158

• Injury prevalence and causality in developing nations: Results from a countrywide population-based survey in Nepal SURGERY Gupta, S., Wong, E. G., Nepal, S., Shrestha, S., Kushner, A. L., Nwomeh, B. C., Wren, S. M. 2015; 157 (5): 843-849

  Abstract

  Traumatic injury affects nearly 5.8 million people annually and causes 10% of the world's deaths. In this study we aimed to estimate injury prevalence, to describe risk-factors and mechanisms of injury, and to estimate the number of injury-related deaths in Nepal, a low-income South Asian country.A cluster randomized, cross-sectional nationwide survey using the Surgeons OverSeas Assessment of Surgical Need tool was conducted in Nepal in 2014. Questions were structured anatomically and designed around a representative spectrum of operative conditions. Two-stage cluster sampling was performed: 15 of 75 districts were chosen randomly proportional to population; within each district, after stratification for urban and rural populations, 3 clusters were randomly chosen. Injury-related results were analyzed.A total of 1,350 households and 2,695 individuals were surveyed verbally, with a response rate of 97%. A total of 379 injuries were reported in 354 individuals (13.1%, 95% confidence interval 11.9-14.5%), mean age of 32.6. The most common mechanism of injury was falls (37.5%), road traffic injuries (19.8%), and burns (14.2%). The most commonly affected anatomic site was the upper extremity (42.0%). Of the deaths reported in the previous year, 16.3% were injury-related; 10% of total deaths may have been averted with access to operative care.This study provides baseline data on the epidemiology of traumatic injuries in Nepal and is the first household-based countrywide assessment of injuries in Nepal. These data provide valuable information to help advise policymakers and government officials for allocation of resources toward trauma care.

  View details for DOI 10.1016/j.surg.2014.12.020

  View details for Web of Science ID 000368557100003

• Surgical care needs of low-resource populations: an estimate of the prevalence of surgically treatable conditions and avoidable deaths in 48 countries. Lancet Gupta, S., Groen, R. S., Kyamanywa, P., Ameh, E. A., Labib, M., Clarke, D. L., Donkor, P., Derbew, M., Sani, R., Kamara, T. B., Shrestha, S., Nwomeh, B. C., Wren, S. M., Price, R. R., Kushner, A. L. 2015; 385: S1-?

  Abstract

  Surgical care needs in low-resource countries are increasingly recognised as an important aspect of global health, yet data for the size of the problem are insufficient. The Surgeons OverSeas Assessment of Surgical Need (SOSAS) is a population-based cluster survey previously used in Nepal, Rwanda, and Sierra Leone.Using previously published SOSAS data from three resource-poor countries (Nepal, Rwanda, and Sierra Leone), a weighted average of overall prevalence of surgically treatable conditions was estimated and the number of deaths that could have been avoided by providing access to surgical care was calculated for the broader community of low-resource countries. Such conditions included, but were not limited to, injuries (road traffic incidents, falls, burns, and gunshot or stab wounds), masses (solid or soft, reducible), deformities (congenital or acquired), abdominal distention, and obstructed delivery. Population and health expenditure per capita data were obtained from the World Bank. Low-resource countries were defined as those with a per capita health expenditure of US$100 or less annually. The overall prevalence estimate from the previously published SOSAS data was extrapolated to each low-resource country. Using crude death rates for each country and the calculated proportion of avoidable deaths, a total number of deaths possibly averted in the previous year with access to appropriate surgical care was calculated.The overall prevalence of surgically treatable conditions was 11·16% (95% CI 11·15-11·17) and 25·6% (95% CI 25·4-25·7) of deaths were potentially avoidable by providing access to surgical care. Using these percentages for the 48 low-resource countries, an estimated 288·2 million people are living with a surgically treatable condition and 5·6 million deaths could be averted annually by the provision of surgical care. In the Nepal SOSAS study, the observed agreement between self-reported verbal responses and visual physical examination findings was 94·6%. Such high correlation helps to validate the SOSAS tool.Hundreds of millions of people with surgically treatable conditions live in low-resource countries, and about 25% of the mortality annually could be avoided with better access to surgical care. Strengthening surgical care must be considered when strengthening health systems and in setting future sustainable development goals.None.

  View details for DOI 10.1016/S0140-6736(15)60796-6

  View details for PubMedID 26313055

• Injury assessment in three low-resource settings: a reference for worldwide estimates Gupta, S., Wren, S. M., Kamara, T. B., Shrestha, S., Kyamanywa, P., Wong, E. G., Groen, R. S., Nwomeh, B. C., Kushner, A. L., Price, R. R. ELSEVIER SCIENCE INC. 2015: 2

  View details for Web of Science ID 000360573400003

• Telephone Follow-Up by a Midlevel Provider After Laparoscopic Inguinal Hernia Repair Instead of Face-to-Face Clinic Visit. JSLS : Journal of the Society of Laparoendoscopic Surgeons / Society of Laparoendoscopic Surgeons Eisenberg, D., Hwa, K., Wren, S. M. 2015; 19 (1)

  Abstract

  The need for more cost- and time-efficient provision of medical care has prompted an interest in remote or telehealth approaches to delivery of health care. We present a study examining the feasibility and outcomes of implementation of a telephone follow-up program for laparoscopic inguinal hernia repair.This is a retrospective review of consecutive patients who prospectively agreed to undergo telephone follow-up after laparoscopic inguinal hernia repair instead of standard face-to-face clinic visits. Patients received a telephone call from a dedicated physician assistant 2 to 3 weeks after surgery and answered a predetermined questionnaire. A face-to-face clinic visit was scheduled based on the results of the call or on patient request.Of 62 patients who underwent surgery, all agreed to telephone follow-up instead of face-to-face clinic visits. Their mean round-trip distance to the hospital was 122 miles. Fifty-five patients (88.7%) successfully completed planned telephone follow-up. Three patients (4.8%) were lost to follow-up, and 4 (6.5%) were erroneously scheduled for a clinic appointment. Of the 55 patients who were reached by telephone, 50 (90.9%) were satisfied and declined an in-person clinic visit. Five patients (9.1%) returned for a clinic appointment based on concerns raised during the telephone call. Of these, 1 was found to have an early hernia recurrence and 1 had a seroma.Telephone follow-up by a midlevel provider after laparoscopic inguinal hernia repair is feasible and effective and is well received by patients.

  View details for DOI 10.4293/JSLS.2014.00205

  View details for PubMedID 25848178

• Burns in Sierra Leone: A population-based assessment BURNS Wong, E. G., Groen, R. S., Kamara, T. B., Stewart, K., Cassidy, L. D., Samai, M., Kushner, A. L., Wren, S. M. 2014; 40 (8): 1748-1753

  Abstract

  Burns remain disproportionately prevalent in developing countries. This study aims to describe the epidemiology of burns in Sierra Leone to serve as a baseline for future programs.A cluster randomized, cross-sectional, countrywide survey was conducted in 2012 in Sierra Leone. With a standardized questionnaire demographics and deaths during the previous 12 months of household members were assessed with the household representative. Thereafter, 2 randomly selected household members were interviewed, elucidating whether participants had ever had a burn in six body regions and determining burn mechanisms and patterns of health care seeking behavior.This study included 1843 households and 3645 individuals. 3.98% (145/3645) of individuals reported at least one burn-injury. The highest proportions of burns were reported in the age groups 0-4 years old (23/426, 5.4%) and 5-14 years old (37/887, 4.17%). The majority of burns (129/145, 89.0%) were caused by a hot liquid/object and the upper, extremities were the most commonly burned body regions, with 36% (53/145) of cases. 21% (30/145) of individuals with burns sought care from a traditional healer.Burns are highly prevalent in Sierra Leone. Further research and resources should be allocated to the care and prevention of thermal injuries.

  View details for DOI 10.1016/j.burns.2014.03.007

  View details for Web of Science ID 000345364400048

• Long-term Results of a Postoperative Pneumonia Prevention Program for the Inpatient Surgical Ward JAMA SURGERY Kazaure, H. S., Martin, M., Yoon, J. K., Wren, S. M. 2014; 149 (9): 914-918

  Abstract

  Pneumonia is the third most common complication in postoperative patients and is associated with significant morbidity and high cost of care. Prevention has focused primarily on mechanically ventilated patients. This study outlines the results of the longest-running postoperative pneumonia prevention program for nonmechanically ventilated patients, to our knowledge.To present long-term results (2008-2012) of a standardized postoperative ward-acquired pneumonia prevention program introduced in 2007 on the surgical ward of our hospital and compare our postintervention pneumonia rates with those captured in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP). We also estimate the cost savings attributable to the pneumonia prevention program.Retrospective cohort study at a university-affiliated Veterans Affairs hospital of all noncardiac surgical patients with ward-acquired postoperative pneumonia.A previously described standardized postoperative pneumonia prevention program for patients on the surgical ward.Ward-acquired postoperative pneumonia.Between 2008 and 2012, there were 18 cases of postoperative pneumonia among 4099 at-risk patients hospitalized on the surgical ward, yielding a case rate of 0.44%. This represents a 43.6% decrease from our preintervention rate (0.78%) (P = .01). The pneumonia rates in all years were lower than the preintervention rate (0.25%, 0.50%, 0.58%, 0.68%, and 0.13% in 2008-2012, respectively). The overall pneumonia rate in ACS-NSQIP was 2.56% (14,033 cases of pneumonia among 547,571 at-risk patients), which is 582% higher than the postintervention rate at our ward. Using a national average of $46,400 in attributable health care cost of postoperative pneumonia and a benchmark of a 43.6% decrease in pneumonia rate achieved at our facility over the 5-year study period, a similar percentage of decrease in pneumonia occurrence at ACS-NSQIP hospitals would represent approximately 6118 prevented pneumonia cases and a cost savings of more than $280 million.The standardized pneumonia prevention program achieved substantial and sustained reduction in postoperative pneumonia incidence on our surgical ward; its wider adoption could improve postoperative outcomes and reduce overall health care costs.

  View details for DOI 10.1001/jamasurg.2014.1216

  View details for PubMedID 25054486

• Surgical training abroad: it's not about the cases. Bulletin of the American College of Surgeons Cloyd, J. M., Wren, S. M. 2014; 99 (9): 42-4

  View details for PubMedID 25272423

• Mental stress experienced by first-year residents and expert surgeons with robotic and laparoscopic surgery interfaces. Journal of robotic surgery Klein, M. I., Mouraviev, V., Craig, C., Salamone, L., Plerhoples, T. A., Wren, S. M., Gaitonde, K. 2014; 8 (2): 149-155

  Abstract

  Prior research has indicated that novices experienced a beneficial stress profile in the robotic surgery (da Vinci) training environment when compared to the laparoscopic surgery training environment. The objective of this study was to assess whether this finding generalizes to expert surgeons. Towards that end, first-year residents' and attending surgeons' performances and subjective stress experiences were assessed in a surgical training task that was performed with the da Vinci and laparoscopic surgery interfaces. This study indicated that both groups exhibited superior performance and lower stress with the da Vinci surgical system than the laparoscopic system. The results provide further support for the sensitivity of the Dundee Stress State Questionnaire in identifying different stress responses experienced by trainees and experts in the minimally invasive surgery environment.

  View details for DOI 10.1007/s11701-013-0446-8

  View details for PubMedID 27637524

• Understanding the reliability of American College of Surgeons National Surgical Quality Improvement Program as a quality comparator. JAMA surgery Rhoads, K. F., Wren, S. M. 2014; 149 (5): 474-?

  View details for DOI 10.1001/jamasurg.2013.4253

  View details for PubMedID 24623013

• An estimate of hernia prevalence in Sierra Leone from a nationwide community survey. Hernia Patel, H. D., Groen, R. S., Kamara, T. B., SAMAI, M., Farahzad, M. M., Cassidy, L. D., Kushner, A. L., Wren, S. M. 2014; 18 (2): 297-303

  Abstract

  A large number of unrepaired inguinal hernias is expected in sub-Saharan Africa where late presentation often results in incarceration, strangulation, or giant scrotal hernias. However, no representative population-based data are available to quantify the prevalence of hernias. We present data on groin masses in Sierra Leone to estimate prevalence, barriers to care, and associated disability.A cluster randomized, cross-sectional household survey of 75 clusters of 25 households with 2 respondents each was designed to calculate the prevalence of and disability caused by groin hernias in Sierra Leone using a verbal head-to-toe examination. Barriers to hernia repairs were assessed by asking participants the main reason for delay in surgical care.Information was obtained from 3,645 respondents in 1,843 households, of which 1,669 (46 %) were male and included in the study. In total, 117 males or 7.01 % (95 % CI 5.64-8.38) reported a soft or reducible swelling likely representing a hernia with four men having two masses. Of the 93.2 % who indicated the need for health care, only 22.2 % underwent a procedure, citing limited funds (59.0 %) as the major barrier to care. On disability assessment, 20.2 % were not able to work secondary to the groin swelling.The results indicate groin masses represent a major burden for the male population in Sierra Leone. Improving access to surgical care for adult patients with hernias and early intervention for children will be vital to address the burden of disease and prevent complications or limitations of daily activity.

  View details for DOI 10.1007/s10029-013-1179-3

  View details for PubMedID 24241327

• The evolving application of single-port robotic surgery in general surgery. Journal of hepato-biliary-pancreatic sciences Qadan, M., Curet, M. J., Wren, S. M. 2014; 21 (1): 26-33

  Abstract

  Advances in the field of minimally invasive surgery have grown since the original advent of conventional multiport laparoscopic surgery. The recent development of single incision laparoscopic surgery remains a relatively novel technique, and has had mixed reviews as to whether it has been associated with lower pain scores, shorter hospital stays, and higher satisfaction levels among patients undergoing procedures through cosmetically-appeasing single incisions. However, due to technical difficulties that arise from the clustering of laparoscopic instruments through a confined working space, such as loss of instrument triangulation, poor surgical exposure, and instrument clashing, uptake by surgeons without a specific interest and expertise in cutting-edge minimally invasive approaches has been limited. The parallel use of robotic surgery with single-port platforms, however, appears to counteract technical issues associated with single incision laparoscopic surgery through significant ergonomic improvements, including enhanced instrument triangulation, organ retraction, and camera localization within the surgical field. By combining the use of the robot with the single incision platform, the recognized challenges of single incision laparoscopic surgery are simplified, while maintaining potential advantages of the single-incision minimally invasive approach. This review provides a comprehensive report of the evolving application single-port robotic surgery in the field of general surgery today.

  View details for DOI 10.1002/jhbp.37

  View details for PubMedID 24124130

• Innovation in Safety, and Safety in Innovation JAMA SURGERY Eisenberg, D., Wren, S. M. 2014; 149 (1): 7-9

  View details for DOI 10.1001/jamasurg.2013.5112

  View details for PubMedID 24352512

• Telehealth Follow-up in Lieu of Postoperative Clinic Visit for Ambulatory Surgery Results of a Pilot Program JAMA SURGERY Hwa, K., Wren, S. M. 2013; 148 (9): 823-827

  Abstract

  IMPORTANCE Telehealth encounters can safely substitute for routine postoperative clinic visits in selected ambulatory surgical procedures. OBJECTIVE To examine whether an allied health professional telephone visit could safely substitute for an in-person clinic visit. DESIGN Prospective case series during a 10-month study period from October 2011 to October 2012 (excluding July and August 2012). SETTING University-affiliated veterans hospital. PATIENTS Ambulatory surgery patients who underwent elective open hernia repair or laparoscopic cholecystectomy during the 10-month study period. INTERVENTIONS Patients were called 2 weeks after surgery by a physician assistant and assessed using a scripted template. Assessment variables included overall health, pain, fever, incision appearance, activity level, and any patient concerns. If the telephone assessment was consistent with absence of infection and return to baseline activities, the patient was discharged from follow-up. Patients who preferred a clinic visit were seen accordingly. MAIN OUTCOMES AND MEASURES Percentage of patients who accepted telehealth follow-up and complications that presented in telehealth patients within 30 days of surgery. RESULTS One hundred fifteen open herniorrhaphy and 26 laparoscopic cholecystectomy patients had attempted telehealth follow-up. Seventy-eight percent (110) of all patients were successfully contacted; of those, 70.8% (63) of hernia patients and 90.5% (19) of cholecystectomy patients accepted telehealth as the sole means of follow-up. Complications in the telehealth patients were zero for cholecystectomy and 4.8% (3) for herniorrhaphy. Nearly all patients expressed great satisfaction with the telephone follow-up method. CONCLUSIONS Telehealth can be safely used in selected ambulatory patients as a substitute for the standard postoperative clinic visit with a high degree of patient satisfaction. Time and expense for travel (7-866 miles) were reduced and the freed clinic time was used to schedule new patients.

  View details for DOI 10.1001/jamasurg.2013.2672

  View details for Web of Science ID 000325212300007

  View details for PubMedID 23842982

• Traumatic injuries in developing countries: report from a nationwide cross-sectional survey of sierra leone. JAMA surgery Stewart, K. A., Groen, R. S., Kamara, T. B., Farahzad, M. M., Samai, M., Cassidy, L. D., Kushner, A. L., Wren, S. M. 2013; 148 (5): 463-469

  Abstract

  OBJECTIVE To use a nationwide household survey tool to provide an estimate of injury prevalence, mechanisms of traumatic injuries, and number of injury-related deaths in a low-income country. DESIGN A randomized, cross-sectional nationwide survey using the Surgeons OverSeas Assessment of Surgical Need tool was conducted in 2012. SETTING Sierra Leone, Africa. PARTICIPANTS Three thousand seven hundred fifty randomly selected participants throughout Sierra Leone. MAIN OUTCOME MEASURES Mechanisms of injury based on age, sex, anatomic location, cause, and sociodemographic factors as well as mechanisms of injury-related deaths in the previous year were the primary outcome measures. RESULTS Data were collected and analyzed from 1843 households and 3645 respondents (98% response rate). Four hundred fifty-two respondents (12%) reported at least 1 traumatic injury in the preceding year. Falls were the most common cause of nonfatal injuries (40%). The extremities were the most common injury site regardless of age or sex. Traffic injuries were the leading cause of injury-related deaths (32% of fatal injuries). CONCLUSIONS This study provides baseline data on the mechanisms of traumatic injuries as well as the sociodemographic factors affecting injury prevalence in one of the world's poorest nations. It is anticipated that these data will provide an impetus for further studies to determine injury severity, associated disability, and barriers to accessing care in these resource-poor areas.

  View details for DOI 10.1001/jamasurg.2013.1341

  View details for PubMedID 23325317

• The influence of intern home call on objectively measured perioperative outcomes. JAMA surgery Kastenberg, Z. J., Rhoads, K. F., Melcher, M. L., Wren, S. M. 2013; 148 (4): 347-351

  Abstract

  HYPOTHESIS In July 2011, surgical interns were prohibited from being on call from home by the new residency review committee guidelines on work hours. In support of the new Accreditation Council for Graduate Medical Education work-hour restrictions, we expected that a period of intern home call would correlate with increased rates of postoperative morbidity and mortality. DESIGN Prospective cohort. SETTING University-affiliated tertiary Veterans Affairs Medical Center. PATIENTS All patients identified in the Veterans Affairs National Surgical Quality Improvement Program database who underwent an operation performed by general, vascular, urologic, or cardiac surgery services between fiscal years (FYs) 1999 and 2010 were included. MAIN OUTCOME MEASURES During FYs 1999-2003, the first call for all patients went to an in-hospital intern. In the subsequent period (FYs 2004-2010), the first call went to an intern on home call. Thirty-day unadjusted morbidity and mortality rates and risk-adjusted observed to expected ratios were analyzed by univariate analysis and joinpoint regression, respectively. RESULTS Unadjusted overall morbidity rates decreased between 1999-2003 and 2004-2010 (12.14% to 10.19%, P =  .003). The risk-adjusted morbidity observed to expected ratios decreased at a uniform annual percentage change of -6.03% (P < .001). Unadjusted overall mortality rates also decreased between the 2 periods (1.76% to 1.26%; P =  .05). There was no significant change in the risk-adjusted mortality observed to expected ratios during the study. CONCLUSIONS The institution of an intern home call schedule was not associated with increased rates of postoperative morbidity or mortality.

  View details for DOI 10.1001/jamasurg.2013.1063

  View details for PubMedID 23715944

• Long-Term Comparison of Endovascular and Open Repair of Abdominal Aortic Aneurysm NEW ENGLAND JOURNAL OF MEDICINE Lederle, F. A., Freischlag, J. A., Kyriakides, T. C., Matsumura, J. S., Padberg, F. T., Kohler, T. R., Kougias, P., Jean-Claude, J. M., Cikrit, D. F., Swanson, K. M. 2012; 367 (21): 1988-1997

  Abstract

  Whether elective endovascular repair of abdominal aortic aneurysm reduces long-term morbidity and mortality, as compared with traditional open repair, remains uncertain.We randomly assigned 881 patients with asymptomatic abdominal aortic aneurysms who were candidates for both procedures to either endovascular repair (444) or open repair (437) and followed them for up to 9 years (mean, 5.2). Patients were selected from 42 Veterans Affairs medical centers and were 49 years of age or older at the time of registration.More than 95% of the patients underwent the assigned repair. For the primary outcome of all-cause mortality, 146 deaths occurred in each group (hazard ratio with endovascular repair versus open repair, 0.97; 95% confidence interval [CI], 0.77 to 1.22; P=0.81). The previously reported reduction in perioperative mortality with endovascular repair was sustained at 2 years (hazard ratio, 0.63; 95% CI, 0.40 to 0.98; P=0.04) and at 3 years (hazard ratio, 0.72; 95% CI, 0.51 to 1.00; P=0.05) but not thereafter. There were 10 aneurysm-related deaths in the endovascular-repair group (2.3%) versus 16 in the open-repair group (3.7%) (P=0.22). Six aneurysm ruptures were confirmed in the endovascular-repair group versus none in the open-repair group (P=0.03). A significant interaction was observed between age and type of treatment (P=0.006); survival was increased among patients under 70 years of age in the endovascular-repair group but tended to be better among those 70 years of age or older in the open-repair group.Endovascular repair and open repair resulted in similar long-term survival. The perioperative survival advantage with endovascular repair was sustained for several years, but rupture after repair remained a concern. Endovascular repair led to increased long-term survival among younger patients but not among older patients, for whom a greater benefit from the endovascular approach had been expected. (Funded by the Department of Veterans Affairs Office of Research and Development; OVER ClinicalTrials.gov number, NCT00094575.).

  View details for DOI 10.1056/NEJMoa1207481

  View details for Web of Science ID 000311340200006

  View details for PubMedID 23171095

• Cost-effectiveness of open versus endovascular repair of abdominal aortic aneurysm in the OVER trial JOURNAL OF VASCULAR SURGERY Stroupe, K. T., Lederle, F. A., Matsumura, J. S., Kyriakides, T. C., Jonk, Y. C., Ge, L., Freischlag, J. A. 2012; 56 (4): 901-?

  Abstract

  This study was conducted to determine the costs and comparative cost-effectiveness of two methods of abdominal aortic aneurysm (AAA) repair in the Open Versus Endovascular Repair (OVER) Veterans Affairs (VA) Cooperative Study, a multicenter randomized trial of 881 patients.The primary outcomes of this analysis were mean total health care cost per life-year and per quality-adjusted life-year (QALY) from randomization to 2 years after. QALYs were calculated from EuroQol (EQ)-5D questionnaires collected at baseline and annually. Health care utilization data were obtained directly from patients and from national VA and Medicare data sources. VA costs were obtained from national VA sources using methods previously developed by the VA Health Economics Resource Center. Costs for non-VA care were determined from Medicare claims data or billing data from the patient's health care providers.After 2 years of follow-up, mean life-years were 1.78 in the endovascular repair group and 1.74 in the open repair group (difference, 0.04; 95% confidence interval [CI], -0.03 to 0.09; P = .29). Mean QALYs were 1.462 in the endovascular group and 1.461 in the open group (difference adjusting for baseline EQ-5D score, 0.006; 95% CI, -0.038 to 0.052; P = .78). Mean graft costs were higher in the endovascular group ($14,052 vs $1363; P < .001), but length of stay was shorter (5.0 vs 10.5 days; P < .001), resulting in a lower mean cost of the hospital admission for the AAA procedure in the endovascular repair group of $37,068 vs $42,970 (difference, -$5901; 95% CI, -$12,135 to -$821; P = .04). After 2 years, total health care costs remained lower in the endovascular group, but the difference was no longer significant (-$5019; 95% CI, -$16,720 to $4928; P = .35). The probability of endovascular repair being less costly and more effective was 70.9% for life-years and 51.4% for QALYs.In this multicenter randomized trial, endovascular AAA repair resulted in lower cost and better survival than open repair after the initial hospitalization for repair; but after 2 years, survival, quality of life, and costs were not significantly different between the two treatments.

  View details for DOI 10.1016/j.jvs.2012.01.086

  View details for Web of Science ID 000309512300001

  View details for PubMedID 22640466

• COMPARISON OF STRESS PROFILES IN NOVICE AND EXPERT SURGEONS USING THE DA VINCI ROBOTIC SYSTEM VERSUS CONVENTIONAL LAPAROSCOPIC SURGERY Klein, M., Mouraviev, V., Salamone, L., Plerhoples, T. A., Wren, S. M., Gaitonde, K. MARY ANN LIEBERT INC. 2012: A420

  View details for Web of Science ID 000308488204184

• The aching surgeon: a survey of physical discomfort and symptoms following open, laparoscopic, and robotic surgery. Journal of robotic surgery Plerhoples, T. A., Hernandez-Boussard, T., Wren, S. M. 2012; 6 (1): 65-72

  Abstract

  There is increasing interest in understanding the toll that operating takes on a surgeon's body. The effect of robotic surgery on surgeon discomfort has not been studied. We sought to document the discomfort of robotic surgery compared with open and laparoscopic surgery and to investigate the factors that affect the risk of physical symptoms. Nineteen-thousand eight-hundred and sixty-eight surgeons from all specialties trained in the use of robots were sent a 26-question online survey and 1,407 responded. One-thousand two-hundred and fifteen surgeons who practiced all three approaches were used in the analysis. Eight-hundred and seventy-one surgeons had physical discomfort or symptoms attributable to operating. Of those with symptoms, 55.4% attributed most of the symptoms to laparoscopic surgery, 36.3% to open surgery, and 8.3% to robotic surgery. A higher case load was predictive of increased symptoms for open and laparoscopic surgery, but not for robotic surgery. Robotic surgery was less likely than open or laparoscopic surgery to lead to neck, back, hip, knee, ankle, foot, and shoulder pain and less likely than laparoscopic surgery to lead to elbow and wrist pain. Robotic surgery was more likely than either open or laparoscopic surgery to lead to eye pain, and more likely than open surgery to lead to finger pain. Nearly a third (30.3%) of surgeons admit to giving consideration to their own discomfort when choosing an operative modality. Robotic surgery has promise in reducing the risk of physical discomfort for the operator. This is important as more surgeons consider their own health when choosing a surgical modality.

  View details for DOI 10.1007/s11701-011-0330-3

  View details for PubMedID 27637981

• The Role of Unconscious Bias in Surgical Safety and Outcomes SURGICAL CLINICS OF NORTH AMERICA Santry, H. P., Wren, S. M. 2012; 92 (1): 137-?

  Abstract

  Racial, ethnic, and gender disparities in health outcomes are a major challenge for the US health care system. Although the causes of these disparities are multifactorial, unconscious bias on the part of health care providers plays a role. Unconscious bias occurs when subconscious prejudicial beliefs about stereotypical individual attributes result in an automatic and unconscious reaction and/or behavior based on those beliefs. This article reviews the evidence in support of unconscious bias and resultant disparate health outcomes. Although unconscious bias cannot be entirely eliminated, acknowledging it, encouraging empathy, and understanding patients' sociocultural context promotes just, equitable, and compassionate care to all patients.

  View details for DOI 10.1016/j.suc.2011.11.006

  View details for Web of Science ID 000301157800014

  View details for PubMedID 22269267

  View details for PubMedCentralID PMC3417145

• Prevention of VTE in nonorthopedic surgical patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest Gould, M. K., Garcia, D. A., Wren, S. M., Karanicolas, P. J., Arcelus, J. I., Heit, J. A., Samama, C. M. 2012; 141 (2): e227S-77S

  Abstract

  VTE is a common cause of preventable death in surgical patients.We developed recommendations for thromboprophylaxis in nonorthopedic surgical patients by using systematic methods as described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines. Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.We describe several alternatives for stratifying the risk of VTE in general and abdominal-pelvic surgical patients. When the risk for VTE is very low (< 0.5%), we recommend that no specific pharmacologic (Grade 1B) or mechanical (Grade 2C) prophylaxis be used other than early ambulation. For patients at low risk for VTE (∼1.5%), we suggest mechanical prophylaxis, preferably with intermittent pneumatic compression (IPC), over no prophylaxis (Grade 2C). For patients at moderate risk for VTE (∼3%) who are not at high risk for major bleeding complications, we suggest low-molecular-weight heparin (LMWH) (Grade 2B), low-dose unfractionated heparin (Grade 2B), or mechanical prophylaxis with IPC (Grade 2C) over no prophylaxis. For patients at high risk for VTE (∼6%) who are not at high risk for major bleeding complications, we recommend pharmacologic prophylaxis with LMWH (Grade 1B) or low-dose unfractionated heparin (Grade 1B) over no prophylaxis. In these patients, we suggest adding mechanical prophylaxis with elastic stockings or IPC to pharmacologic prophylaxis (Grade 2C). For patients at high risk for VTE undergoing abdominal or pelvic surgery for cancer, we recommend extended-duration, postoperative, pharmacologic prophylaxis (4 weeks) with LMWH over limited-duration prophylaxis (Grade 1B). For patients at moderate to high risk for VTE who are at high risk for major bleeding complications or those in whom the consequences of bleeding are believed to be particularly severe, we suggest use of mechanical prophylaxis, preferably with IPC, over no prophylaxis until the risk of bleeding diminishes and pharmacologic prophylaxis may be initiated (Grade 2C). For patients in all risk groups, we suggest that an inferior vena cava filter not be used for primary VTE prevention (Grade 2C) and that surveillance with venous compression ultrasonography should not be performed (Grade 2C). We developed similar recommendations for other nonorthopedic surgical populations.Optimal thromboprophylaxis in nonorthopedic surgical patients will consider the risks of VTE and bleeding complications as well as the values and preferences of individual patients.

  View details for DOI 10.1378/chest.11-2297

  View details for PubMedID 22315263

  View details for PubMedCentralID PMC3278061

• Racial and ethnic differences in lymph node examination after colon cancer resection do not completely explain disparities in mortality CANCER Rhoads, K. F., Cullen, J., Ngo, J. V., Wren, S. M. 2012; 118 (2): 469-477

  Abstract

  In 1999, a multidisciplinary panel of experts in colorectal cancer reviewed the relevant medical literature and issued a consensus recommendation for a 12-lymph node (LN) minimum examination after resection for colon cancer. Some authors have shown racial/ethnic differences in receipt of this evidence-based care. To date, however, none has investigated the correlation between disparities in LN examination and disparities in outcomes after colon cancer treatment.This retrospective analysis used California Cancer Registry linked to California Office of Statewide Health Planning and Development discharge data (1996-2006). Chi-square analysis, logistic regression, and Cox proportional hazard models predicted disparities in receipt of an adequate examination and the effect of an inadequate exam on mortality and disparities. Patients with stage I and II colon cancers undergoing surgery in California were included; patients with stage III and IV disease were excluded.A total of 37,911 records were analyzed. Adequate staging occurred in fewer than half of cases. An inadequate examination (<12 LNs) was associated with higher mortality rates. Hispanics had the lowest odds of receiving an adequate exam; however, blacks, not Hispanics, had the highest risk of mortality compared with whites. This disparity was not completely explained by inadequate LN examination.Inadequate LN exam occurs often and is associated with increased mortality. There are disparities in receipt of the minimum exam, but this only explains a small part of the observed disparity in mortality. Improving the quality of LN examination alone is unlikely to correct colon cancer disparities.

  View details for DOI 10.1002/cncr.26316

  View details for PubMedID 21751191

• Innovative Leadership of Casualty Care ARCHIVES OF SURGERY Wren, S. M. 2011; 146 (12): 1357

  View details for Web of Science ID 000298256900005

• Solitary metastatic clear cell carcinoma to the spleen. Rare tumors Zayed, M. A., Kosek, J., Wren, S. M. 2011; 3 (4)

  Abstract

  A 57-year-old with a 9-year history of increased abdominal girth, presented with increased abdominal pain, anemia, and acute renal failure. His past medical history was only remarkable for a previous lung cancer 21 years ago that was treated with a right upper lung lobectomy. A computed tomography (CT) scan of the patient's abdomen showed a solitary 20×20×25cm cystic splenic mass. The patient underwent an urgent splenectomy. Intra-operatively a large splenic cystic cavity was found with a solid inferior splenic mass. An exhaustive histological analysis of the splenic mass confirmed a clear cell carcinoma with low malignant potential that likely represented a metastatic lesion from the patient's previous distant lung cancer. Postoperatively the patient recovered well and at 1-year followup the patient demonstrated no further evidence of metastatic disease. This case is extremely unique and provides a very rare example of a metastatic solitary clear cell carcinoma to the spleen, with a presumed latency period of more than 20 years.

  View details for DOI 10.4081/rt.2011.e43

  View details for PubMedID 22355498

• Single-Port Robotic Cholecystectomy Results From a First Human Use Clinical Study of the New da Vinci Single-Site Surgical Platform ARCHIVES OF SURGERY Wren, S. M., Curet, M. J. 2011; 146 (10): 1122-1127

  Abstract

  To report our results from a first human use clinical study with the da Vinci Surgical single-site instrumentation in patients with gallbladder disease and to perform a retrospective comparison with traditional multiport laparoscopic cholecystectomy.Ten patients underwent robotic single-port cholecystectomy performed with the da Vinci Si robot and novel da Vinci single-site instrumentation. Outcomes and operative times were compared with patients undergoing traditional multiport laparoscopic cholecystectomy during the same period.Tertiary care Veterans Administration hospital.Outpatients older than 18 years with an American Society of Anesthesiologists class of 1 to 3, no prior upper abdominal surgery, and diagnosis of noninflammatory biliary disease.Single-site robotic cholecystectomy.Operative time, complications up to 30 days, pain scores, and overall satisfaction.Nine of 10 patients had completion of robotic single-site cholecystectomy. Average operating room time was 105.3 minutes compared with an average of 106.1 minutes in the standard laparoscopic group. There were no serious adverse events in the robotic surgery group, with an average follow-up of 3 or more months.Robotic single-port cholecystectomy is feasible and comparable with standard laparoscopic cholecystectomy in the Veterans Administration medical center setting.

  View details for DOI 10.1001/archsurg.2011.143

  View details for PubMedID 21690436

• Postoperative Pneumonia-Prevention Program for the Inpatient Surgical Ward 33rd Annual Meeting of the Association-of-VA-Surgeons Wren, S. M., Martin, M., Yoon, J. K., Bech, F. ELSEVIER SCIENCE INC. 2010: 491–95

  Abstract

  Postoperative pneumonia can lead to increased morbidity, length of hospital stay, and costs. Pneumonia-prevention programs have been successfully implemented in ICU settings, but no program exists for surgical ward patients.A pilot prevention program was designed and implemented based on literature review. The program consisted of education of physicians and ward staff and a standardized postoperative electronic order set consisting of incentive spirometer, chlorhexidine oral hygiene, ambulation, and head-of-bed elevation. Quarterly staff meetings discussed the results of and compliance with the program. The intervention commenced in April 2007. Baseline incidence of inpatient ward pneumonia was calculated from the National Surgical Quality Improvement Program database for fiscal year (FY) 2006 and FY 2007. Postintervention incidence was calculated in the same manner from FY 2007 through FY 2008. Any patient who contracted pneumonia in the ICU was excluded from analysis.There was a significant decrease in ward pneumonia incidence from 0.78% in the preintervention group compared with 0.18% in the postintervention group (p = 0.006), representing an 81% decrease in incidence from 2006 to 2008.The pneumonia-prevention program was very successful in diminishing postoperative pneumonia on the surgical ward. There was a highly statistically significant 4-fold decrease in pneumonia incidence after program implementation. The interventions were not costly but did require ongoing communication and cooperation between physician and nursing leadership to achieve compliance with the measures. This program has great potential for dissemination to hospital surgical wards and could decrease inpatient postoperative pneumonias.

  View details for DOI 10.1016/j.jamcollsurg.2010.01.009

  View details for PubMedID 20347742

• Death After Colectomy It's Later Than We Think 79th Annual Meeting of the Pacific-Coast-Surgical-Association Visser, B. C., Keegan, H., Martin, M., Wren, S. M. AMER MEDICAL ASSOC. 2009: 1021–27

  Abstract

  Clinical outcomes are increasingly subject to objective assessment and professional accountability. Informed consent relies on accurate estimation of operative risk. Current scoring systems for assessment of operative mortality after colorectal surgery (CRS) almost uniformly report 30-day mortality and may not represent true risk.Prospective cohort.University-affiliated Veterans Affairs Medical Center.All patients who underwent resections of the colon and/or rectum (as the principal operation) at a single hospital whose data are captured in the Veterans Affairs National Surgical Quality Improvement Program (VA-NSQIP) database from January 1, 2000, through December 31, 2006.Mortality at 30 days and 90 days.The VA-NSQIP cohort included 186 patients who underwent CRS, including 148 patients who underwent elective procedures (79.6%) and 38 patients who underwent emergency procedures (20.4%). All but 8 patients were men, with a median age of 67 years (range, 26-92 years). Laparoscopic operations comprised 24.2% and open operations comprised 75.8%. Most (60.8%) were performed for neoplasms. The actual 30-day mortality rates (all, elective, and emergency procedures) were 4.3%, 1.4%, and 15.8%, respectively. These rates closely mirrored the calculated VA-NSQIP risk-adjusted observed-to-expected ratio for 30-day mortality (4.8%, 1.8%, and 18.2%, respectively). However, mortality at 90 days increased substantially to 9.1%, 4.1%, and 28.9%, respectively.The 30-day mortality significantly underreports the true risk of death after CRS. The 90-day mortality rate should be included as a standard outcome measure after CRS because it serves as a better estimation of risk for counseling patients.

  View details for PubMedID 19917938

• Multimedia manuscript. Endoscopic clipping of a post-Whipple pancreatic bleed. Surgical endoscopy Kaltenbach, T., Wren, S., Schumacher, L., Soetikno, R. 2009; 23 (9): 2159-2160

  Abstract

  Bleeding after pancreaticoduodenectomy most often occurs from the gastro- or duodeno-jejunal anastomosis. Bleeding at the pancreatic surface would be the most difficult to treat because it typically requires surgical resection of the pancreatic remnant-a surgery that has significant morbidity and mortality. Data that describe the role of endoscopy in the management of pancreaticojejunostomy bleeding are limited.We present the case of a 69-year-old man who had massive upper gastrointestinal bleeding on postoperative day 2 after a pyloric sparing Whipple procedure for cholangiocarcinoma. We endoscopically approached this massive upper gastrointestinal bleed by understanding the postsurgical anatomy to consider all of the potential bleeding sources: duodenojejunostomy, hepaticojejunstomy, and the pancreaticojejunostomy. Using a pediatric colonoscope with water jet capabilities, active bleeding could be seen originating from the cut pancreatic surface. Complete hemostasis was achieved after placement of two clips. We clipped again two clays later due to a minor rebleeding episode. We repeated endoscopy on postoperative day 6 for surveillance of the site. All clips were in place and there was no evidence of bleeding. The patient did well without recurrent bleeding and was discharged home on postoperative day 7. Six-month follow-up showed no recurrent bleeding episodes or development of fistulas.Endoscopic treatment of a bleeding site on the pancreatic surface of a pancreaticojejunostomy can be successful during the immediate postoperative period. Such an attempt at endoscopic hemostasis may prevent the need for completion pancreatectomy.

  View details for DOI 10.1007/s00464-009-0357-y

  View details for PubMedID 19277780

• Endoscopic clipping of a post-whipple pancreatic bleed SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES Kaltenbach, T., Wren, S., Schumacher, L., Soetikno, R. 2009; 23 (9): 2159-2160

  Abstract

  Bleeding after pancreaticoduodenectomy most often occurs from the gastro- or duodeno-jejunal anastomosis. Bleeding at the pancreatic surface would be the most difficult to treat because it typically requires surgical resection of the pancreatic remnant-a surgery that has significant morbidity and mortality. Data that describe the role of endoscopy in the management of pancreaticojejunostomy bleeding are limited.We present the case of a 69-year-old man who had massive upper gastrointestinal bleeding on postoperative day 2 after a pyloric sparing Whipple procedure for cholangiocarcinoma. We endoscopically approached this massive upper gastrointestinal bleed by understanding the postsurgical anatomy to consider all of the potential bleeding sources: duodenojejunostomy, hepaticojejunstomy, and the pancreaticojejunostomy. Using a pediatric colonoscope with water jet capabilities, active bleeding could be seen originating from the cut pancreatic surface. Complete hemostasis was achieved after placement of two clips. We clipped again two clays later due to a minor rebleeding episode. We repeated endoscopy on postoperative day 6 for surveillance of the site. All clips were in place and there was no evidence of bleeding. The patient did well without recurrent bleeding and was discharged home on postoperative day 7. Six-month follow-up showed no recurrent bleeding episodes or development of fistulas.Endoscopic treatment of a bleeding site on the pancreatic surface of a pancreaticojejunostomy can be successful during the immediate postoperative period. Such an attempt at endoscopic hemostasis may prevent the need for completion pancreatectomy.

  View details for DOI 10.1007/s00464-009-0357-y

  View details for Web of Science ID 000269209700035

• The Impact of the Pathologist on Lymph Node Yield Morrow, E., Lee, L., Wren, S. SPRINGER. 2009: 68–68

  View details for Web of Science ID 000207857400226

• Male Patients Above Age 60 have as Good Outcomes as Male Patients 50-59 Years Old at 1-Year Follow-up After Bariatric Surgery OBESITY SURGERY Wool, D., Bellatorre, N., Wren, S., Eisenberg, D. 2009; 19 (1): 18-21

  Abstract

  It is estimated that 25% of Americans older than 60 years are obese. Male gender and advanced age are indicators of increased risk for bariatric surgery. Good results have been shown in patients older than 50, but nearly all published studies include a large majority of females, and few include patients >60 years old. In this study, we examined the results of males over 60 years old.We reviewed a prospective database of 107 consecutive patients who underwent bariatric surgery between April 2002 and June 2007 at the Palo Alto VA. Of these, 60 patients were males older than 50 and available for follow-up 12 months postoperatively. There were 47 males 50-59 years old (group I) and 13 males older than 60 years (group II). Data were analyzed using Student's t test.Mean preoperative body mass index was similar in both groups (49.4 vs. 47.5 kg/m(2); p = 0.468). Length of hospital stay was similar (3.2 vs. 3.5 days; p = 0.678), but early morbidity was higher in group II patients (30.8% vs. 8.5%; p = 0.037). Morbidity included urinary tract infection, cardiac arrhythmias, and early bowel obstruction. Excess weight loss after 1 year was not significantly different (63.6% vs. 60.6%; p = 0.565). Diabetes resolution or improvement was seen in 87% of group I patients and 90% of group II patients.Despite a higher early morbidity rate, obese males >/=60 years old perform as well as male patients 50-59 years old with respect to excess weight loss, mortality, length of stay, and improvement of diabetes, at 1 year postoperatively.

  View details for DOI 10.1007/s11695-008-9734-1

  View details for Web of Science ID 000262281700004

  View details for PubMedID 18855082

• Esophageal Cancer: Initial Staging METHODS OF CANCER DIAGNOSIS, THERAPY, AND PROGNOSIS Schumacher, L. Y., Baril, N. B., Wren, S. M., Hayat, M. A. 2008: 83–95

  View details for Web of Science ID 000269606200010

• Metastatic colon adenocarcinoma mimicking herpes zoster JOURNAL OF THE AMERICAN COLLEGE OF SURGEONS Goodwin, T. L., Wren, S. M. 2007; 205 (4): 625-625

  View details for DOI 10.1016/j.jamcollsurg.2007.01.073

  View details for PubMedID 17903740

• Care within a Veterans Hospital - Earlier detection of colon cancer SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES van Roessel, P., Rouse, R. V., Wren, S. M. 2007; 21 (8): 1434-1440

  Abstract

  In 1998 the Veterans Administration mandated an externally monitored targeted colon cancer screening rate that was expected to result in earlier cancer detection and improved patient survival. The effectiveness of the protocol was evaluated in a retrospective case series at a tertiary care Veterans Administration Hospital that included all patients with the diagnosis of colon cancer between 1991 and 2003.Tumor stage, tumor location, and patient survival data were recorded and compared to National Cancer Data Base (NCDB) benchmarks.The study facility had a greater percentage of early cancers and fewer later stage cancers than the NCDB benchmark. Overall survival was better for the VA cohort compared to NCDB (all-cause 5-year survival: VA, 0.72; NCDB, 0.47. p < or = .001).The VA facility had a significantly greater percentage of early cancers and fewer stage III or IV cancers compared to a national benchmark and significantly improved survival compared to the national benchmark.

  View details for DOI 10.1007/s00464-006-9184-6

  View details for PubMedID 17294311

• Short- and long-term outcomes of standardized EMR of nonpolypoid (flat and depressed) colorectal lesions >= 1 cm (with video) GASTROINTESTINAL ENDOSCOPY Kaltenbach, T., Friedland, S., Maheshwari, A., Ouyang, D., Rouse, R. V., Wren, S., Soetikno, R. 2007; 65 (6): 857-865

  Abstract

  Nonpolypoid (flat and depressed) colorectal lesions are increasingly recognized. Their endoscopic removal requires specialized EMR techniques, which are more complex to perform. Outcomes data on EMR of nonpolypoid neoplasms in the United States is needed.To determine the safety and efficacy of EMR in the resection of nonpolypoid colorectal neoplasms > or = 1 cm.Retrospective analysis.Veterans Affairs Palo Alto Health Care System.Over a 5-year period, patients who underwent EMR for nonpolypoid colorectal lesions > or = 1 cm.A standardized approach that included lesion assessment, classification, inject-and-cut EMR technique, reassessment, and treatment of residual tissue.Complete resection, bleeding, perforation, development of advanced cancer, and death.A total of 100 patients (125 lesions: 117 flat and 8 depressed) met inclusion criteria. Mean size was 16.7 +/- 7 mm (range, 10-50 mm). Histology included 5 submucosal invasive cancers, 5 carcinomas in situ, and 91 adenomas. Thirty-eight patients (48 lesions) did not receive surveillance colonoscopy: 8 had surgery, 16 had hyperplastic pathology, and 14 did not undergo repeat examination. Surveillance colonoscopy was performed on 62 patients (77 lesions). Complete resection was achieved in 100% of these patients after 1 to 3 surveillance colonoscopies. All patients received follow-up (mean [standard deviation] = 4.5 +/- 1.4 years); none developed colorectal cancer or metastasis.Single endoscopist, retrospective study.A standardized EMR (inject-and-cut) technique is a safe and curative treatment option in nonpolypoid colorectal neoplasms (> or = 1 cm) in the United States.

  View details for DOI 10.1016/j.gie.2006.11.035

  View details for PubMedID 17466205

• Transnasal small-caliber esophagogastroduodenoscopy for preoperative evaluation of the high-risk morbidly obese patient SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES Alami, R. S., Schuster, R., Friedland, S., Curet, M. J., Wren, S. M., Soetikno, R., Morton, J. M., Safadi, B. Y. 2007; 21 (5): 758-760

  Abstract

  Esophagogastroduodenoscopy (EGD) is an important facet of the preoperative evaluation for bariatric surgery. Morbidly obese patients are at high risk for airway complications during this procedure, and an attractive alternative is transnasal EGD. This report describes a series of patients evaluated successfully using this technique.All patients undergoing preoperative transnasal small-caliber EGD for morbid obesity surgery between September 2004 and June 2005 at a Veterans Affairs Hospital were included in the analysis. The variables assessed were the adequacy of the examination, patient tolerance, the need for sedation, and the ability to perform interventions.The study enrolled 25 patients (17 men and 8 women) with an average age of 55 years (range, 44-63 years) and an average body mass index (BMI) of 47 kg/m2 (range, 38-69 kg/m2). All the patients met the 1991 National Institutes of Health (NIH) Consensus Conference Criteria for bariatric surgery and were undergoing preoperative evaluation. The most common comorbidities were hypertension (82%), diabetes mellitus (80%), and obstructive sleep apnea (68%). All 25 patients had successful cannulation of the duodenum's second portion with excellent tolerance. There were no sedation requirements for 23 (92%) of the 25 patients. Significant pathology was found in 14 (56%) of the 25 patients, including hiatal hernia (28%), gastritis (16%), esophageal intestinal metaplasia (16%), esophagitis (12%), gastric polyps (8%), gastric ulcer (4%) and esophageal varices (4%). Biopsies were indicated for 12 patients and successful for all 12 (100%).Transnasal small-caliber EGD is a feasible and safe alternative to conventional EGD for the preoperative evaluation of patients undergoing bariatric surgery. It requires minimal to no sedation in a population at high risk for complications in this setting. In addition, this technique is effective in identifying pathology that requires preoperative treatment and offers a complete examination with biopsy capabilities. This technique should be considered for all morbidly obese patients at high risk for airway compromise during EGD.

  View details for DOI 10.1007/s00464-006-9101-z

  View details for Web of Science ID 000246351800013

  View details for PubMedID 17235723

• Preoperativc positron emission tomography to evaluate potentially rcsectable hepatic colorectal metastases - Invited critique ARCHIVES OF SURGERY Wren, S. M. 2006; 141 (12): 1227

  View details for DOI 10.1001/archsurg.141.12.1227

  View details for Web of Science ID 000242669500016

• The use of acellular dermal matrix for contaminated abdominal wall defects: wound status predicts success 30th Annual Surgical Symposium of the Association-of-VA-Surgeons Schuster, R., Singh, J., Safadi, B. Y., Wren, S. M. EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC. 2006: 594–97

  Abstract

  Contaminated abdominal wall fascial defects present a challenging problem. The use of human acellular dermal matrix (AlloDerm; LifeCell Corp., Branchburg, NJ) provides a novel method of primary closure of abdominal wall defects in this setting. The aim of the current study was to determine what factors predicted fascial wall failure as determined by the presence of hernia on follow-up exam after AlloDerm placement.All patients who underwent surgery for contaminated abdominal wall fascial defects with placement of AlloDerm from June 2003 to September 2005 at a tertiary care Veterans Affairs hospital were included in the analysis. Patients were followed until hernia recurrence or last clinic visit.Eighteen patients had AlloDerm placed for contaminated fascial defects and all were included in the analysis. Primary wound closure was performed on 12/18 (67%) patients, with 6/18 (33%) patients initially left with open wounds. Patients with open wounds were treated with wound vacuum-assisted closure (VAC) devices (4/6) or saline dressings (2/6). Overall ventral hernia recurrence rate was 50% (9/18) with an average follow up of 9.1 months. Patients who had primary wound closure at the completion of the operation had a 33% (4/12) recurrence rate. Patients who did not have primary wound closure had an 83.3% (5/6) recurrence rate. The significant difference shows (P = .03) that open wound status predicts recurrence. The average size of AlloDerm sheets used was 164.0 cm2 in the closed group and 146.2 cm2 in the primary open wound group (P = .64). Average cost per patient was 4680 dollars for AlloDerm.These data suggest that an open wound in the postoperative period after AlloDerm placement for treatment of contaminated fascial defects is associated with a high probability of hernia recurrence. Our data do not support the use of this expensive material unless there is a good chance of having a closed wound.

  View details for DOI 10.1016/j.amjsurg.2006.08.017

  View details for Web of Science ID 000241820000007

  View details for PubMedID 17071190

• Concurrent gastric bypass and repair of anterior abdominal wall hernias OBESITY SURGERY Schuster, R., Curet, M. J., Alami, R. S., Morton, J. M., Wren, S. M., Safadi, B. Y. 2006; 16 (9): 1205-1208

  Abstract

  Many patients seeking surgical treatment for morbid obesity present with anterior abdominal wall hernias. Although principles of hernia repair involve a tension-free repair with the use of prosthetic mesh, there is concern about the use of mesh in gastric bypass surgery due to potential contamination with the contents of the gastrointestinal tract and resultant mesh infection. We report our series of patients undergoing Roux-en-Y gastric bypass (RYGBP) and simultaneous anterior abdominal wall hernia repair.All patients who underwent simultaneous RYGBP surgery and anterior abdominal wall hernia repair were reviewed.12 patients underwent concurrent RYGBP and anterior wall hernia repair. There were 5 women and 7 men with average age 54.9 +/- 8.5 years (range 35 to 64) and average body mass index (BMI) 50.4 +/- 10.3 kg/m(2) (range 38 to 70). Two open and 10 laparoscopic RYGBP operations were performed. Nine patients (75%) underwent incisional hernia repairs and 3 patients (25%) underwent umbilical hernia repair concurrent with gastric bypass. Average size of defect was 14.7 +/- 13.4 cm(2). One patient had primary repair and 11 patients had prosthetic mesh repair: polypropylene in 3 patients (25%) and polyester in 8 patients (67%). With a 14.1 +/- 9.3 month follow-up, there have been no mesh infections and 2 recurrences, one in the patient who underwent primary repair and one in a patient repaired with polyester mesh but with two previous failed incisional hernia repairs.Concurrent RYGBP and repair of anterior abdominal wall hernias is safe and feasible. In order to optimize success, tension-free principles of hernia repair with the use of prosthetic mesh should be followed since no mesh infections occurred in our series.

  View details for PubMedID 16989705

• Laparoscopic Roux-en-Y gastric bypass at a Veterans Affairs and high-volume academic facilities: a comparison of institutional outcomes 29th Annual Surgical Symposium of the Association-of-VA-Surgeons Alami, R. S., Morton, J. M., Sanchez, B. R., Curet, M. J., Wren, S. M., Safadi, B. Y. EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC. 2005: 821–25

  Abstract

  Outcomes of bariatric surgery have been linked to institutional case volume. The objective of our study was to compare outcome of laparoscopic Roux-en-y gastric bypass (RYGB) in 2 settings: a low-volume Veterans Affairs (VA) and a high-volume university hospital (UH).Over a period of 27 months, 140 patients underwent RYGB (137 laparoscopic, 3 open) performed by 1 surgeon. Fifty-five were performed at a VA and 85 at a UH with an annual caseload close to 300.The body mass index in both groups was similar, but patients at the VA were older, mostly men, and more likely to have hypertension (HTN), obstructive sleep apnea, and diabetes mellitus (DM). Operative and anesthesia times were significantly longer at the VA. There were no differences in 30-day mortality (none), major morbidity, conversion rates, or reoperation rates.Laparoscopic RYGB can be performed safely at a VA facility despite a higher risk population and low annual volume.

  View details for DOI 10.1016/j.amjsurg.2005.07.027

  View details for Web of Science ID 000232935200030

  View details for PubMedID 16226965

• Preoperative oral antibiotics in colorectal surgery increase the rate of Clostridium difficile colitis 76th Annual Meeting of the Pacific-Coast-Surgical-Association Wren, S. M., Ahmed, N., Jamal, A., Safadi, B. Y. AMER MEDICAL ASSOC. 2005: 752–55

  Abstract

  Bowel preparation traditionally consists of cathartics, oral antibiotics, and intravenous antibiotics. We hypothesize that the use of oral antibiotics in bowel preparation results in a higher rate of postoperative Clostridium difficile colitis.Retrospective case-controlled study of elective colon surgery patients; January 1997 to June 2003.Tertiary care veterans administration hospital.Records of patients who underwent elective colorectal surgery (n = 304) were reviewed. Patients with bowel obstruction or emergent operation were excluded.Detection of C difficile toxin A/B by enzyme-linked immunosorbent assay in a stool specimen within 30 days of surgery.All 304 patients received both cathartics and intravenous antibiotics. Of 304 patients, 107 (35.1%) received oral antibiotics. The rate of postoperative C difficile colitis was 4.2% in the entire study population. The rate of C difficile infection was higher in patients who received oral antibiotics (7.4%) compared with patients who did not receive oral antibiotics (2.6%; P = .03). There were no C difficile-related mortalities.Oral nonabsorbable antibiotics in bowel preparation resulted in a higher rate of C difficile infection. This may be due to the additional effect of oral antibiotics on normal bowel flora. We recommend that oral nonabsorbable antibiotics not be used in preoperative bowel preparation regimens since postoperative C difficile infection can lead to additional morbidity, length of stay, and hospital costs.

  View details for PubMedID 16103284

• Comparison of training on two laparoscopic simulators and assessment of skills transfer to surgical performance JOURNAL OF THE AMERICAN COLLEGE OF SURGEONS Youngblood, P. L., Srivastava, S., Curet, M., Heinrichs, W. L., Dev, P., Wren, S. M. 2005; 200 (4): 546-551

  Abstract

  Several studies have investigated the transfer of surgical trainees' skills acquired on surgical simulators to the operating room setting. The purpose of this study was to compare the effectiveness of two laparoscopic surgery simulators by assessing the transfer of skills learned on simulators to closely matched surgical tasks in the animal laboratory.In this post-test-only Control group study design, 46 surgically naive medical student volunteers were randomly assigned to one of three groups: Tower Trainer group (n = 16), LapSim group (n = 17), and Control group (n = 13). Outcomes measures included both time and accuracy scores on three laparoscopic tasks (Task 1: Grasp and Place; Task 2: Run the Bowel; Task 3: Clip and Cut) performed on live anesthetized pigs, and a global rating of overall performance as judged by four experienced surgeons.The Tower Trainer group performed significantly better than the Control group on 1 of 7 outcomes measures-Task 3: Time (p < 0.032), although the LapSim group performed significantly better than the Control group on 2 of 7 measures-Task 3: Time (p < 0.008) and Global score (p < 0.005). In comparing the two simulators, the LapSim group performed significantly better than the Tower Trainer group on 3 of 7 outcomes measures-Task 2: Time (p < 0.032), Task 2: Accuracy (p < 0.030) and Global score (p < 0.005), although the Tower Trainer group did not perform significantly better than the LapSim group on any measure.This study demonstrated that naive subjects trained on a virtual-reality part-task trainer performed better on live surgical tasks in a porcine model as compared with those trained with a traditional box trainer. These findings could aid in selection of appropriate training methodologies.

  View details for DOI 10.1016/j.jamcollsurg.2004.11.011

  View details for PubMedID 15804468

• Introducing laparoscopic Roux-en-Y gastric bypass at a Veterans Affairs medical facility 28th Annual Surgical Symposium of the Association-of-VA-Surgeons Safadi, B. Y., Kieran, J. A., Hall, R. G., Morton, J. M., Bellatorre, N., Shinoda, E., Johnson, P. J., Curet, M. J., Wren, S. M. EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC. 2004: 606–10

  Abstract

  Previous studies have shown that advanced age, diabetes, and male gender are associated with higher morbidity and mortality after bariatric surgery. Those risk factors are characteristic of patients in the Veterans Affairs (VA) health care system. Laparoscopic Roux-en-Y gastric bypass (RYGB) has become an established treatment modality for morbid obesity. Our objective was to review the initial experience with laparoscopic (RYGB) for morbid obesity at our VA facility.A retrospective review was used.Between May of 2002 and April of 2004, 40 patients underwent laparoscopic RYGB. All patients met National Institutes of Health consensus statement guidelines for bariatric surgery. There were 30 (75%) male and 10 (25%) female patients, with an average age of 49.9 +/- 8.7 years and an average body mass index (BMI) of 48.1 +/- 8.5 kg/m(2). Preoperative comorbidities included diabetes mellitus (DM) in 59%, hypertension in 79%, and obstructive sleep apnea in 74.4%. The procedure was converted to an open procedure in 3 patients (7.5%). There were no mortalities. Immediate (within 30 days) complications developed in 9 (22.5%) patients, necessitating abdominal re-operation in 3 patients (7.5%). The median length of hospital stay was 3 days. Late complications (>30 days) developed in 8 (20%) patients. Percent excess weight loss at 3, 6, and 12 months was 44% (n = 34), 59% (n = 29), and 70.0% (n = 22), respectively. In 23 patients who were followed-up for more than 3 months, DM resolved in 79% and improved in 21% at a mean follow-up evaluation of 13 months.Laparoscopic RYGB can be performed with acceptable morbidity and with good short-term results in a VA hospital setting. Morbid obesity is prevalent in the VA patient population and access to bariatric surgery should be an available alternative.

  View details for DOI 10.1016/j.amjsurg.2004.07.021

  View details for PubMedID 15546580

• Institutional commitment to rectal cancer screening results in earlier-stage cancers on diagnosis ANNALS OF SURGICAL ONCOLOGY Battat, A. C., Rouse, R. V., Dempsey, L., Safadi, B. Y., Wren, S. M. 2004; 11 (11): 970-976

  Abstract

  The Veterans Administration hospitals underwent an institutional directive in 1998 to meet a colorectal cancer screening (CRCS) standard. This intervention should result in an increase in the hospital's screening rate and percentage of early-stage rectal cancers diagnosed.A retrospective review, from 1991 to 2002, of our institution's pathology and cancer registry databases for rectal cancers. CRCS data were obtained from the Veterans Administration Prevention Disease Index. Cancer stage at diagnosis was compared before and after the directive and was compared with the National Cancer Data Base and the Surveillance, Epidemiology, and End Results data.The rate of CRCS was 55% in 1998 and increased to 75% in 2003. During the 11 years studied, a total of 147 rectal cancers were diagnosed. After the Veterans Administration directive, there was a significant increase in stage 0 cancers (P < .02) and an overall migration to earlier-stage cancers. Our Veterans Administration hospital had a significantly greater percentage of stage 0 cancers both before (P < .007) and after the directive (P < .00) and had fewer stage 3 cancers after the directive (P < .03) compared with National Cancer Data Base data. Compared with Surveillance, Epidemiology, and End Results data, the Palo Alto Veterans Affairs Health Care System had more local disease (P < .03) and less regional disease (P < .006).These data suggest that a monitored institutional directive may significantly increase early detection of rectal cancers. This should result in a greater survival rate and lower local recurrence rate, because survival is predicated on stage at presentation. This may serve as a model for other health-care systems.

  View details for DOI 10.1245/ASO.2004.03.047

  View details for PubMedID 15525825

• Utilization of laparoscopic antireflux surgery at a single Veterans Affairs facility compared with the Veterans Affairs national trend 27th Annual Surgical Symposium of the Association-of-VA-Surgeons Safadi, B. Y., Kown, M., Wren, S. EXCERPTA MEDICA INC-ELSEVIER SCIENCE INC. 2003: 505–8

  Abstract

  The widespread use of laparoscopy in the early 1990s has led to an increase in the utilization of antireflux procedures for the treatment of gastroesophageal reflux disease (GERD). This trend has been observed in the private sector, but not within the Department of Veterans Affairs (VA) health care system. Published data suggest that among patients undergoing antireflux surgical procedures, those in the VA were less likely than those in the private sector to undergo laparoscopic surgery. The objective of this study was to determine the trend in the use of laparoscopic antireflux surgical procedures at our VA facility and compare it with the national VA trend.All antireflux operations performed at our VA facility from 1991 to 2002 were recorded along with techniques used. National VA data on the utilization of antireflux procedures from 1991 to 1999 was extracted from a recent publication by Finlayson et al.In contrast to the trend observed nationally across VA hospitals, the rate of utilization of antireflux surgery at our VA facility has increased compared with baseline in 1991. Of 83 fundoplications performed from 1991 to 2002, 76 (92%) were attempted or completed laparoscopically. The conversion rate from laparoscopic to open approach was 6.6%.We have observed an increase in the utilization of antireflux surgery since 1991 at our VA facility. In addition, most fundoplications were performed laparoscopically. These findings are in contrast to published national VA data. The presence of surgeons with interest in laparoscopy, institutional support, and a dedicated esophageal function laboratory may explain these findings.

  View details for DOI 10.1016/j.amjsurg.2003.07.025

  View details for PubMedID 14599615

• A novel technique to treat ruptured umbilical hernias in patients with liver cirrhosis and severe ascites JOURNAL OF LAPAROENDOSCOPIC & ADVANCED SURGICAL TECHNIQUES-PART A Melcher, M. L., Lobato, R. L., Wren, S. M. 2003; 13 (5): 331-332

  Abstract

  The full-thickness skin erosion (rupture) of an umbilical hernia in a patient with end-stage liver disease can lead to significant morbidity and mortality. Here, we present a case report of the use of a novel technique to treat a patient with this condition. The use of a fibrin-based tissue adhesive provides a means of managing such patients medically.

  View details for PubMedID 14617394

• Positron emission tomography in the initial staging of esophageal cancer 73rd Annual Meeting of the Pacific-Coast-Surgical-Association Wren, S. M., Stijns, P., Srinivas, S. AMER MEDICAL ASSOC. 2002: 1001–6

  Abstract

  To assess the value of positron emission tomography (PET) compared with computed tomography (CT) in the initial staging of esophageal cancer.Case series.Tertiary care veterans hospital.Patients with newly diagnosed esophageal cancers from January 1996 through May 2001 who underwent both CT and PET scanning within 4 weeks were included in the study (n = 24). Only patients who underwent pathological or radiographic follow-up were included.The sensitivity, specificity, and negative and positive predictive values of CT and PET were determined based on a criterion standard of pathological staging in 16 patients (67%) and follow-up imaging in 8 patients (33%).For staging regional lymph node involvement, CT and PET scans showed no statistically significant difference in sensitivity (57% and 71%, respectively) and specificity (71% and 86%, respectively). For detection of metastatic disease, CT and PET showed no significant difference in sensitivity (83% and 67%, respectively) and specificity (75% and 92%, respectively). There was no significant difference in clinical decision making when the results of both tests were discordant.There was no significant difference between the 2 imaging modalities in the initial staging of esophageal cancer. The CT scan was a sensitive indicator of distant metastases, whereas PET was more specific. It is unclear what additional role PET scanning should have in the initial screening of patients.

  View details for Web of Science ID 000177920800004

  View details for PubMedID 12215149

• Effective management of bleeding during tumor resection with a collagen-based hemostatic agent AMERICAN SURGEON Chapman, W. C., Wren, S. M., LEBOVIC, G. S., Malawer, M., Sherman, R., Block, J. E. 2002; 68 (9): 802-807

  Abstract

  In a prospective controlled trial hemostatic effectiveness of a novel collagen-based composite (CoStasis) was compared with a collagen sponge applied with manual pressure at diffusely bleeding sites after surgical tumor resection. The proportion of subjects achieving complete cessation of bleeding within 10 minutes (i.e., hemostatic success) and the time to "complete hemostasis" were determined at raw surgical sites after tumor resection among 23 experimental and 30 control subjects. There was a similar distribution in tumor types (e.g., benign vs malignant) evaluated between treatment groups. A significantly greater proportion of experimental subjects achieved complete hemostasis within 10 minutes of observation compared with controls [23 of 23 (100%) vs 21 of 30 (70%); P = 0.003]. The median time required to achieve complete hemostasis was more than three times longer for subjects treated with the collagen sponge compared with subjects treated with CoStasis (243 vs 78 seconds; P = 0.0001). Approximately 80 per cent of experimental subjects achieved complete hemostasis within 2 minutes compared with only 35 per cent of controls. There were no adverse events related to the experimental treatment in this study. These results support the use of this novel hemostatic agent to control diffuse surgical site bleeding after tumor resection at diverse anatomical locations.

  View details for Web of Science ID 000181916500015

  View details for PubMedID 12356154

• Intravascular hemolysis from a Clostridium perfringens liver abscess JOURNAL OF THE AMERICAN COLLEGE OF SURGEONS Kreidl, K. O., Green, G. R., Wren, S. M. 2002; 194 (3): 387-387

  View details for PubMedID 11893140

• Decompressive colonoscopy with intracolonic vancomycin administration for the treatment of severe pseudomembranous colitis SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES Shetler, K., Nieuwenhuis, R., Wren, S. M., Triadafilopoulos, G. 2001; 15 (7): 653-659

  Abstract

  We explored the potential of early decompressive colonoscopy with intracolonic vancomycin administration as an adjunctive therapy for severe pseudomembranous Clostridium difficile colitis with ileus and toxic megacolon.We reviewed the symptoms, signs, laboratory tests, radiographic findings, and outcomes from the medical records of seven patients who experienced eight episodes of severe pseudomembranous colitis with ileus and toxic megacolon. All seven patients underwent decompressive colonoscopy with intracolonic perfusion of vancomycin.Fever, abdominal pain, diarrhea, abdominal distention, and tenderness were present in all patients. Five of seven patients were comatose, obtunded, or confused, and six of the seven required ventilatory support. The white blood cell count was greater than 16,000 in seven cases (six patients). Colonoscopy showed left-side pseudomembranous colitis in one patient, right-side colitis in one patient, and diffuse pseudomembranous pancolitis in five patients. Two patients were discharged with improvement. Five patients had numerous medical problems leading to their death. Complete resolution of pseudomembranous colitis occurred in four patients. One patient had a partial response, and two patients failed therapy.Colonoscopic decompression and intracolonic vancomycin administration in the management of severe, acute, pseudomembranous colitis associated with ileus and toxic megacolon is feasible, safe, and effective in approximately 57% to 71% of cases.

  View details for PubMedID 11591962

• Results of a screening program for prostate cancer in patients scheduled for abdominoperineal resection for colorectal pathologic findings UROLOGY Terris, M. K., Wren, S. M. 2001; 57 (5): 943-945

  Abstract

  Because of the difficulty of accessing the prostate for tissue sampling after surgical removal of the rectum and obliteration of the anus, we started an early detection program for prostate cancer in all men scheduled for abdominoperineal resection.Twenty consecutive men were screened for prostatic adenocarcinoma before planned abdominoperineal resection for colorectal pathologic findings. Patients were 48 to 77 years old (mean 66.9). Screening included serum prostate-specific antigen determination and digital rectal examination. Those patients with suspicious findings underwent transrectal ultrasound-guided sextant biopsies of the prostate.One patient was excluded because of a prior history of prostate cancer. Six (31.6%) of the remaining 19 patients demonstrated elevated prostate-specific antigen levels (greater than 4.0 ng/mL); two of these patients also had an abnormal digital rectal examination. Transrectal ultrasound and prostate biopsies in these 6 patients revealed prostatic adenocarcinoma in 3 patients (50% of those undergoing biopsies or 15.8% of those screened). The 13 patients who did not undergo prostate biopsies had prostate-specific antigen levels from 0.4 to 2.4 ng/mL (mean 0.9) and normal prostate glands according to the digital rectal examinations.Screening for prostate cancer in men 50 years old or older with 10 years or longer life expectancy before they undergo abdominoperineal resection detects a significant number of prostatic malignancies and should be encouraged.

  View details for Web of Science ID 000168644300021

  View details for PubMedID 11337299

• A novel collagen-based composite offers effective hemostasis for multiple surgical indications: Results of a randomized controlled trial SURGERY Chapman, W. C., Sherman, R., Boyce, S., Malawer, M., Hill, A., Buncke, G., Block, J. E., Fung, C. J., Clavien, P., Lee, K. F., LEBOVIC, G. S., Wren, S. M., Diethrich, E., Goldstein, R. 2001; 129 (4): 445-450

  Abstract

  Intraoperative bleeding is ubiquitous during open surgical procedures and uniformly effective hemostasis remains elusive. We conducted a randomized controlled trial to determine the effectiveness of a novel collagen-based composite (CoStasis Surgical Hemostat) compared with standard methods of hemostasis during general, hepatic, cardiac, and orthopedic operations.Hemostatic treatment was assigned randomly to 347 subjects; 318 subjects (167 CoStasis, 151 controls) underwent operation, received treatment, and provided hemostatic success data. CoStasis was applied to the bleeding site without manual pressure as a sprayable liquid composite of bovine microfibrillar collagen, bovine thrombin, and autologous plasma. Manual compression was used as the control hemostat. Hemostatic success was achieved if bleeding had ceased completely within 10 minutes (3 minutes for cardiac subjects). The time to controlled bleeding (ie, slight oozing) and time to complete hemostasis were recorded for all subjects.Hemostatic success was achieved in more than 90% (153/167) of CoStasis subjects compared with 58% (88/151) of control subjects (P =.01). Superior hemostatic effectiveness with CoStasis was realized in every surgical specialty: general (77/79 vs 49/75, P =.01), hepatic (38/39 vs 20/29, P =.01), cardiac (28/37 vs 17/37, P =.02), and orthopedic (10/12 vs 2/10, P =.01). The duration of bleeding was also significantly shorter with CoStasis. The median time to controlled bleeding (42 seconds vs 150 seconds, P =.0001) and time to complete hemostasis (75 seconds vs 252 seconds, P =.0001) were both markedly longer with the control intervention. There were no serious adverse events related to the use of CoStasis.CoStasis is more effective at controlling and stopping diffuse intraoperative bleeding than standard methods of hemostasis in 4 distinct surgical indications representing a wide variety of operative interventions.

  View details for Web of Science ID 000167986600010

  View details for PubMedID 11283536

• External beam radiotherapy for synchronous rectal and prostatic tumors. Urology Siu, W., Kapp, D. S., Wren, S. M., King, C., Terris, M. K. 2001; 57 (4): 800-?

  Abstract

  Two patients were diagnosed with large rectal tumors and localized prostate cancer. The prostate-specific antigen level at diagnosis was 7.9 ng/mL and 9.0 ng/mL in the 2 patients. Knowledge of the presence of both tumors and their close proximity allowed creation of a modified three-dimensional conformal radiotherapy plan to treat both tumors. The patients had no evidence of rectal tumor recurrence and their prostate-specific antigen level was 0.5 ng/mL and 0.7 ng/mL at 1 and 2 years after therapy, respectively. We conclude that efficient, effective pelvic irradiation can be designed for synchronous rectal and prostate malignancies.

  View details for PubMedID 11306416

• Does an infected peripancreatic fluid collection or abscess mandate operation? ANNALS OF SURGERY Baril, N. B., Ralls, P. W., Wren, S. M., Selby, R. R., Radin, R., Parekh, D., Jabbour, N., Stain, S. C. 2000; 231 (3): 361-367

  Abstract

  To assess the treatment of peripancreatic fluid collections or abscess with percutaneous catheter drainage (PCD).Surgical intervention has been the mainstay of treatment for infected peripancreatic fluid collections and abscesses. Increasingly, PCD has been used, with mixed results reported in the literature.A retrospective chart review of 1993 to 1997 was performed on 82 patients at a tertiary care public teaching hospital who had computed tomography-guided aspiration for suspected infected pancreatic fluid collection or abscess. Culture results, need for subsequent surgical intervention, length of stay, and death rate were assessed.One hundred thirty-five aspirations were performed in 82 patients (57 male patients, 25 female patients) with a mean age of 40 years (range 17-68). The etiologies were alcohol (41), gallstones (32), and other (9). The mean number of Ranson's criteria was four (range 0-9). All patients received antibiotics. Forty-eight patients had evidence of pancreatic necrosis on computed tomography scan. Cultures were negative in 40 patients and positive in 42. Twenty-five of the 42 culture-positive patients had PCD as primary therapy, and 6 required subsequent surgery. Eleven patients had primary surgical therapy, and five required subsequent surgery. Six patients were treated with only antibiotics. The death rates were 12% for culture-positive patients and 8% for the entire 82 patients.Historically, patients with positive peripancreatic aspirate culture have required operation. This series reports an evolving strategy of reliance on catheter drainage. PCD should be considered as the initial therapy for culture-positive patients, with surgical intervention reserved for patients in whom treatment fails.

  View details for Web of Science ID 000085635500009

  View details for PubMedID 10714629

  View details for PubMedCentralID PMC1421007

• Clinical and pathologic overlap in nonsteroidal anti-inflammatory drug-related small bowel diaphragm disease and the neuromuscular and vascular hamartoma of the small bowel AMERICAN JOURNAL OF SURGICAL PATHOLOGY Cortina, G., Wren, S., Armstrong, B., Lewin, K., Fajardo, L. 1999; 23 (11): 1414-1417

  Abstract

  Diaphragm disease (DD) is a radiographically subtle cause of small bowel obstruction and is part of the spectrum of diseases associated with nonsteroidal anti-inflammatory drug injury. The neuromuscular and vascular hamartoma (NMVH) is a nonepithelial hamartomatous, submucosally based proliferation of mature submucosal elements capable of causing small bowel obstruction. The authors report two patients in whom the clinical setting and gross pathology are that of DD, but the histologic characterization is identical to that described for NMVH. It is probable that in some patients the two diseases overlap so that some patients readily fit the criteria for both entities.

  View details for Web of Science ID 000083467900013

  View details for PubMedID 10555011

• Antiviral cytotoxic activity across a species barrier in mixed xenogeneic chimeras: Functional restriction to host MHC JOURNAL OF IMMUNOLOGY Colson, Y. L., Tripp, R. A., Doherty, P. C., Wren, S. M., Neipp, M., El-Ezz, A. Y., Ildstad, S. T. 1998; 160 (8): 3790-3796

  Abstract

  Reconstitution of lethally irradiated mice with a mixture of mouse and rat bone marrow cells (mouse + rat-->mouse) results in mixed xenogeneic chimerism and donor-specific tolerance. The current study demonstrates that mouse and rat T lymphocytes that have developed in xenogeneic chimeras are restricted to Ag presentation by mouse, but not rat, APC. Restriction to host Ags results in functional immunocompetence with generation of antiviral cytotoxic activity in vivo, within and across species barriers. These data demonstrate for the first time that the host thymus is sufficient to support development and positive selection of functional cross-species T lymphocytes. The superior immunocompetence, as compared with fully xenogeneic (rat-->mouse) chimeras, may prove to be of significant benefit in the clinical application of xenotransplantation to solid organ transplantation and immune reconstitution for AIDS.

  View details for Web of Science ID 000072970400023

  View details for PubMedID 9558082

• Is cryosurgical ablation appropriate for treating hepatocellular cancer? 104th Scientific Session of the Western-Surgical-Association Wren, S. M., Coburn, M. M., Tan, M., Daniels, J. R., Yassa, N., Carpenter, C. L., Stain, S. C. AMER MEDICAL ASSOC. 1997: 599–604

  Abstract

  To examine the feasibility and efficacy of cryosurgical ablation as treatment for patients with cirrhosis with unresectable hepatocellular carcinoma.Retrospective case series.A tertiary public hospital and a cancer center.Twelve patients with cirrhosis with hepatocellular carcinoma (stage II, 2; stage III, 1; stage IVA, 7; stage IVB, 2).Cryosurgical ablation of all identifiable tumors. Nine patients treated with curative intent were included in the survival analysis, and 3 were treated for palliation. Five patients were treated with preoperative intra-arterial chemoembolization.Perioperative complications and the effects of tumor stage and chemoembolization were examined. Patient survival and disease-free interval were calculated by life-table analysis.No perioperative deaths occurred and 1 patient had 2 postoperative complications: pneumonia and biloma. The mean survival has been 19 months after cryosurgical ablation and 29 months after diagnosis. Three of the 9 patients treated with curative intent died with recurrence at a mean of 17 months after cryosurgical ablation. Four patients are alive with recurrence at a mean of 19 months after cryosurgical ablation and 38 months after diagnosis. Two patients with stage II disease have no evidence of recurrence 10 and 32 months after cryosurgical ablation.Cryosurgical ablation is feasible and safe for treatment of hepatocellular carcinoma in patients with cirrhosis. The technique is primarily palliative but may provide a possibility of cure in patients with lower-stage disease.

  View details for Web of Science ID A1997XE52600008

  View details for PubMedID 9197851

• Color flow sonography in evaluating the resectability of periampullary and pancreatic tumors JOURNAL OF ULTRASOUND IN MEDICINE Ralls, P. W., Wren, S. M., Radin, R., Stain, S. C., Yang, J., Parekh, D. 1997; 16 (2): 131-140

  Abstract

  Over the past several years, we have developed a technique to assess the resectability of periampullary and pancreatic tumors using color flow sonography. This is a feasibility study to determine if sonography with color flow imaging can play a role in evaluating patients with periampullary and pancreatic tumors. This study comprises a retrospective analysis of 51 patients referred for color flow sonographic evaluation of resectability of periampullary and pancreatic neoplasm. Scanning was performed with state-of-the-art color flow sonographic systems. Vessels that were touched or occluded by tumor were categorized according to a Pancreatic Color Doppler Score. Other factors affecting resectability (metastasis, enlarged nodes) were recorded. Sonographic findings were correlated with surgical resectability and pathologic findings regarding tumor margins. The color flow study was complete technically (all index vessels visualized) in 49 of 51 patients (96%). In all, 643 of 647 vessels (99.4%) were imaged. Forty-five patients had sufficient surgical, pathologic, or clinical proof to be included in the resectability analysis. All 18 patients with circumferential tumor or vascular occlusion (Pancreatic Color Doppler Score 4 and 5) were found to have unresectable disease. All 10 patients in whom tumor did not touch (Pancreatic Color Doppler Score 0) had negative margins. All 30 patients considered to have unresectable tumors sonographically could not be resected. Patients in this category had one or more of the following: positive pathologic margins, positive nodes, liver metastasis, or not clinically resectable. Six of 15 considered resectable sonographically (40%) were unresectable for cure. Surgeons believed that color flow sonography influenced management in 10 of 45 patients (22% overall). Color flow sonography, a painless, noninvasive, and relatively inexpensive examination, may be an effective screening tool to evaluate periampullary and pancreatic neoplasms for resectability. Our data show that color flow sonography can correctly predict unresectability of periampullary and pancreatic neoplasms. Any future evaluation of imaging and management of periampullary and pancreatic tumors should include color flow sonography.

  View details for Web of Science ID A1997XT74600009

  View details for PubMedID 9166806

• The role of anticoagulation in pylephlebitis 48th Annual Meeting of the Southwestern Surgical Congress Baril, N., Wren, S., Radin, R., Ralls, P., Stain, S. CAHNERS PUBL CO. 1996: 449–53

  Abstract

  Pylephlebitis may complicate any intra-abdominal infection and carries a high mortality rate. Acute cases are usually anticoagulated to prevent thrombus extension and enteric ischemia; however, the role of anticoagulation has not been clearly defined.Over a 3-year period, pylephlebitis was diagnosed in 44 patients with portal vein thrombosis on computed tomography scan with fever, leukocytosis, and/or positive blood cultures. The charts were reviewed for etiology, extent of venous thrombosis, and method and results of treatment.Eighteen patients were hypercoagulable, due to clotting factor deficiencies (6), malignancy (8), or AIDS (4). Fifteen patients had mesenteric vein involvement. Thirty-two patients were not anticoagulated, and 5 died (3 with hypercoagulable states and 2 with normal clotting function). Twelve patients were anticoagulated, and none developed subsequent bowel infarction or died.Patients with pylephlebitis and a hypercoagulable state due to neoplasms or clotting factor deficiencies should be anticoagulated. Patients with normal clotting function and mesenteric vein involvement may also benefit. We believe anticoagulation in patients with thrombus isolated to the portal vein and normal clotting function may be unnecessary.

  View details for Web of Science ID A1996VR81800009

  View details for PubMedID 8942542

• Selective management of hepatic adenomas Annual Meeting of the Southern-California-Chapter of the American-College-of-Surgeons Ault, G. T., Wren, S. M., Ralls, P. W., Reynolds, T. B., Stain, S. C. SOUTHEASTERN SURGICAL CONGRESS. 1996: 825–29

  Abstract

  Hepatic adenomas are uncommon hepatic neoplasms that may be identified after life-threatening hemorrhage, or as an incidental radiologic finding. The incidence of malignant transformation is unknown, and the correct treatment strategy is unclear. We examined our 10-year experience in the management of 12 patients with hepatic adenomas. Eleven adults (mean age of 37.6 years) and one 3-month-old were identified. Nine of 10 adult females (90%) were taking a hormonal preparation at the time of diagnosis. Four patients with tumor sizes of 1.0 to 4.0 cm were observed after cessation of oral contraceptives. Four patients with lesions of 5.5 to 13 cm underwent surgical resection. Three had malignant transformation, and two of the three had increased Alpha-fetoprotein levels. Four patients presented with acute hemorrhage and were treated initially by hepatic arterial embolization. We conclude that management of adenomas should be individualized based on their size and mode of presentation. Patients with lesions less than 5 cm and normal alpha-fetoprotein can be safely observed off oral contraceptives and followed by radiologic imaging. Lesions >5 cm should be considered for surgical resection due to the risk of malignancy. Hepatic arterial embolization is a new approach for acute hemorrhage.

  View details for Web of Science ID A1996VJ94300010

  View details for PubMedID 8813164

• Assessment of resectability of pancreatic head and periampullary tumors by color flow Doppler sonography 67th Annual Session of the Pacific-Coast-Surgical-Association Wren, S. M., Ralls, P. W., Stain, S. C., Kasiraman, A., Carpenter, C. L., Parekh, D. AMER MEDICAL ASSOC. 1996: 812–17

  Abstract

  To examine the sensitivity of color flow Doppler ultrasonography in assessing resectability of pancreatic head and periampullary tumors.Validation cohort study.Tertiary care public hospital.Thirty-seven patients with pancreatic head or periampullary cancer were studied by color flow Doppler examination of the relevant blood vessels.A pancreatic Doppler score (PDS) was defined as the closest circumferential contact of the tumor to the superior mesenteric vein, superior mesenteric artery, or portal vein. A PDS of 1 indicated no contact (n = 9); PDS 2, less than 50% contact (n = 10); PDS 3, 50% to 99% contact (n = 7); and PDS 4, encasement (n = 11). The PDS was compared with operative and histologic resection margins.The lack of vascular invasion was confirmed operatively in 7 of 7 patients with a PDS of 1, and 6 patients who underwent resection had clear histologic margins. Nine (90%) of 10 patients with a PDS of 2 were confirmed to have no vascular invasion, and 3 (43%) of 7 patients who underwent resection had clear margins. Five (83%) of 6 patients with a PDS of 3 had correct operative findings, and both patients who underwent resection had positive margins. Operative confirmation of encasement was found in all 7 patients with a PDS of 4 who had operative exploration, and none underwent resection.Color flow Doppler sonography and PDS predicted resectability and the histologic margin status (positive predictive value, 97%). Patients with a PDS of 1 are predicted to have clear histologic margins after resection. Patients with a PDS of 4 have unresectable tumors, and nonoperative palliation should be considered. Patients with a PDS of 2 or 3 have a high likelihood of positive histologic margins after resection and may be candidates for neoadjuvant chemotherapy.

  View details for Web of Science ID A1996VA59100005

  View details for PubMedID 8712903

• A NONLETHAL CONDITIONING APPROACH TO ACHIEVE DURABLE MULTILINEAGE MIXED CHIMERISM AND TOLERANCE ACROSS MAJOR, MINOR, AND HEMATOPOIETIC HISTOCOMPATIBILITY BARRIERS JOURNAL OF IMMUNOLOGY Colson, Y. L., Wren, S. M., Schuchert, M. J., Patrene, K. D., Johnson, P. C., Boggs, S. S., Ildstad, S. T. 1995; 155 (9): 4179-4188

  Abstract

  Reconstitution of lethally irradiated mice with a mixture of syngeneic and allogeneic (A+B-->A) bone marrow results in multilineage mixed allogeneic chimerism, donor-specific transplantation tolerance, superior immunocompetence and resistance to graft-vs-host disease. However, the morbidity and mortality associated with lethal irradiation would be a major limitation to the clinical application of chimerism to induce tolerance for solid organ grafts or treat other nonmalignant hematologic diseases. We report here that durable multilineage mixed allogeneic chimerism and donor-specific transplantation tolerance for skin and primarily vascularized allografts can be achieved across multiple histocompatibility barriers using a nonmyeloablative radiation-based approach. The percentage of B10 mouse recipients that engrafted directly correlated with the degree of disparity between donor and recipient and the dose of total body irradiation administered. Although the occurrence of engraftment following conditioning with doses of total body irradiation of > or = 600 cGy was similar for animals receiving bone marrow disparate at MHC or MHC, minor and hematopoietic (Hh-1) loci (67% vs 78%), the level of donor chimerism was significantly less when multiple histocompatibility barriers were present (94.6 +/- 3.8% vs 37.5 +/- 12.5%). Treatment of the recipient with cyclophosphamide 2 days following allogeneic bone marrow transplantation reduced the dose of radiation sufficient for reliable engraftment to only 500 cGy of total body irradiation, regardless of MHC and Hh-1 disparity. Donor chimerism was stable and present in all lineages, with production of lymphoid (T and B cell), NK, and myeloid (erythrocyte, platelet, granulocyte, and macrophage) cells. Mixed chimeras exhibited donor-specific tolerance in vitro, as assessed by mixed lymphocyte culture (MLR) and cytotoxicity (CML) assays, and in vivo to skin and primarily vascularized cardiac allografts. The observation that engraftment and tolerance can be achieved across multiple histocompatibility barriers using nonmyeloablative recipient conditioning may allow allogeneic bone marrow transplantation to be applied to nonmalignant disease states in which lethal conditioning cannot be justified, including the induction of donor-specific tolerance for solid organ transplantation and the treatment of hemoglobinopathies and enzyme deficiency states.

  View details for Web of Science ID A1995TB46800008

  View details for PubMedID 7594573

• INDIVIDUAL ASSESSMENT OF VISUAL-PERCEPTION BY SURGEONS OBSERVING THE SAME LAPAROSCOPIC ORGANS WITH VARIOUS IMAGING-SYSTEMS Annual Meeting of the Society-of-American-Gastrointestinal-Endoscopic-Surgeons (SAGES) Berci, G., Wren, S. M., Stain, S. C., Peters, J., PAZPARTLOW, M. SPRINGER VERLAG. 1995: 967–73

  Abstract

  Laparoscopic surgery necessitates that operations be performed via a television screen; therefore, image quality is crucial in determining the final outcome. Electronic imaging systems are constantly undergoing revisions and incorporating new ideas. Recently, we have been confronted with a variety of systems, and we, as operators, have no idea what the differences are between the old and the newer systems. As clinicians, we have no electronic yardstick available to compare the options presented or to check the specifications. This study examines critical aspects of image perception. General surgeons, gynecologists, operating-room nurses, as well as allied health personnel all experienced in laparoscopic surgery participated as test subjects. A blinded study was performed in which various camera systems (single chip, three-chip, digitized and nondigitized) were displayed in random fashion. Porcine abdominal areas were displayed using the various imaging units. Participants graded image perception based on the following characteristics: sharpness, color, contrast, and depth of field. The audience were blinded to the types, brand, and number of cameras utilized. A significant preference was shown for digitized systems (P < 0.0001). Also, digitized single-chip cameras scored higher than three-chip cameras (P < 0.05). We propose thorough testing by surgeons and nursing personnel before deciding what type of equipment to purchase.

  View details for Web of Science ID A1995RT66600003

  View details for PubMedID 7482214

• PHENOTYPIC CHARACTERIZATION OF A NOVEL BONE-MARROW-DERIVED CELL THAT FACILITATES ENGRAFTMENT OF ALLOGENEIC BONE-MARROW STEM-CELLS BLOOD Kaufman, C. L., Colson, Y. L., Wren, S. M., Watkins, S., SIMMONS, R. L., Ildstad, S. T. 1994; 84 (8): 2436-2446

  Abstract

  Bone marrow transplantation is an accepted therapy for hematologic malignancies, aplastic anemia, metabolic disorders, and solid tumors. However, graft-versus-host disease (GVHD) and failure of engraftment have limited the widespread application of this technology to nonmalignant disease states. The use of purified bone marrow stem cells has been suggested as an approach to promote engraftment yet avoid GVHD. Although bone marrow stem cells, purified by cell sorting, engraft and repopulate lethally irradiated genetically identical recipients, they do not engraft in major histocompatibility complex (MHC)-disparate allogeneic recipients. We report for the first time the characterization of a novel cell population of donor bone marrow origin, separate from the hematopoietic stem cell, that facilitates engraftment of purified allogeneic bone marrow stem cells in an MHC-specific fashion without causing GVHD. Although 1,000 purified stem cells (c-kit+/Sca-1+/lineage-) reliably repopulate syngeneic mouse recipients, 10 times that number do not engraft in MHC-disparate allogeneic recipients. The addition of as few as 30,000 facilitating cells (CD8+/CD45R+/TCR-) is sufficient to permit engraftment of purified stem cells in MHC-disparate recipients. The cell surface phenotype of this purified cellular population differs significantly from other characterized lineages of lymphoid or myeloid origin. Based on multiparameter rare-events cell sorting, the facilitating fraction is CD8+, CD3+, CD45R+, Thy 1+, class IIdim/intermediate but alpha beta-TCR- and gamma delta-TCR-. This cellular population comprises approximately 0.4% of the total bone marrow and is separate from the hematopoietic stem cell. The coadministration of purified facilitating cells plus stem cells to optimize engraftment yet avoid GVHD may expand the potential application of bone marrow transplantation to disease states in which the morbidity and mortality associated with conventional BMT cannot be justified.

  View details for Web of Science ID A1994PL35900005

  View details for PubMedID 7919363

• EVIDENCE FOR EARLY TH2 T-CELL PREDOMINANCE IN XENOREACTIVITY TRANSPLANTATION Wren, S. M., Wang, S. C., Thai, N. L., Conrad, B., Hoffman, R. A., Fung, J. J., SIMMONS, R. L., Ildstad, S. T. 1993; 56 (4): 905-911

  Abstract

  Two distinct subsets of CD4+ Th lymphocytes have been characterized by their cytokine profiles: Th 1 (TH1) and Th 2 (TH2). While TH1 cells predominate in cell-mediated responses, TH2 cells support the humoral response. We have examined the mRNA cytokine profile of normal mouse lymphocytes in response to alloantigen versus xenoantigen (rat) in MLC, and present evidence to suggest that early in proliferative responses, alloreactivity is dominated primarily by TH1-type lymphocytes, while xenoreactivity is predominantly TH2. Normal mouse lymphocyte-responding cells were cultured in a one-way MLR with either allo or xeno antigen and examined for production of mRNA for cytokines characteristically produced by TH1 (IL-2, IFN-gamma) or TH2 (IL-4, IL-10) cells. Semiquantitative reverse transcription-polymerase chain reaction analysis was performed for mouse IL-2, IL-4, IL-10, and IFN-gamma mRNA. In the mouse anti-rat xeno response, mRNA for TH2 gene products were upregulated, with greater levels of IL-4 and IL-10 at 24 and 48 hr when compared with controls. In contrast, upregulation of mRNA for TH1 gene products occurred in the mouse anti-mouse allo response, with higher levels of IL-2 and IFN-gamma at 24 and 48 hr. In the anti-xeno response, upregulation of all 4 cytokines occurred by day 4 and peak levels of mRNA for all cytokines examined were 2-3 times that seen for the peak anti-allogeneic response. These data suggest that early xenorecognition may differ from allorecognition by differential activation of the TH2 subset. A better understanding of the balance between Th subset function and cytokine profile in allo and xeno reactivity may allow a more targeted and specific approach to control the early events in xenograft rejection.

  View details for Web of Science ID A1993MD80500025

  View details for PubMedID 8212215

• CHARACTERIZATION OF THE IMMUNOSUPPRESSIVE EFFECTS OF NITRIC-OXIDE IN GRAFT-VS-HOST DISEASE JOURNAL OF IMMUNOLOGY Hoffman, R. A., Langrehr, J. M., Wren, S. M., Dull, K. E., Ildstad, S. T., McCarthy, S. A., SIMMONS, R. L. 1993; 151 (3): 1508-1518

  Abstract

  The generation of nitric oxide (.N = O) during in vitro assays involving lymphocyte-macrophage interaction can result in profound inhibition of lymphocyte proliferation. The present study examined whether .N = O synthesis plays a role in the suppression observed in immune function assays during graft vs host disease (GvHD). By using a parent to F1 model to induce GvHD (C57BL/6J to C57BL/6J x DBA 2J F1), a mild but transient increase in serum NO2- plus NO3- levels was observed on day 12 after inoculation. Resident peritoneal macrophages obtained from mice with GvHD demonstrated enhanced .N = O synthesis in response to LPS, compared with control F1 peritoneal macrophages. Similarly, when splenocytes from GvHD mice were cultured with Con A or LPS enhanced supernatant NO2- levels were observed, compared with control F1 mice. Addition of NG-monomethyl-L-arginine (NMA), a competitive inhibitor of .N = O synthesis, resulted in decreased NO2- levels and greatly enhanced proliferation in response to Con A. Addition of NMA to LPS-stimulated cultures did not enhance proliferation, perhaps as the result of the paucity of B cells in the GvHD population. LPS-induced .N = O synthesis by GvHD splenocytes was blocked by anti-IFN-gamma mAb, whereas Con A-induced .N = O synthesis was relatively unaffected by similar concentrations of anti-IFN-gamma mAb, suggesting different mechanisms of induction of .N = O synthesis. A proliferative response of splenocytes from mice with GvHD to third-party alloantigen was not detectable, even in the presence of NMA. The suppression observed when splenocytes from GvHD animals were added to control TNP-modified self cultures was partially reversed in the presence of NMA. These results demonstrate that .N = O synthesis in both splenocyte and peritoneal macrophage populations from GvHD mice is enhanced, revealing that in vivo priming of macrophages for .N = O synthesis occurs during GvHD. Some, but not all, in vitro tests of immune function by using GvHD splenocytes are suppressed by the generation of .N = O.

  View details for Web of Science ID A1993LP72500037

  View details for PubMedID 8335943

• CD4+ T-CELLS, BUT NOT CD8+ T-CELLS, MEDIATE THE BREAKING OF TOLERANCE IN MIXED ALLOGENEIC CHIMERAS (B10+B10.BR-]B10) TRANSPLANTATION Wren, S. M., HRONAKES, M. L., Ildstad, S. T. 1993; 55 (6): 1382-1389

  Abstract

  Reconstitution of mouse recipients with a mixture of syngeneic plus allogeneic bone marrow (A+B-->A) results in stable mixed lymphohematopoietic chimerism and donor-specific transplantation tolerance. Previously, it was reported that administration of large numbers of unmanipulated host-type splenocytes to neonatal or adult radiation bone marrow chimeras resulted in a loss of chimerism and donor-specific transplantation tolerance. To characterize the phenotype(s) of cells that were responsible for this loss of chimerism, we performed depletion of various subsets of unmanipulated B10 splenocytes prior to infusion into mixed allogeneic chimeras (B10 + B10.BR-->B10). Recipients were followed serially to identify changes in the level of donor chimerism and by in vitro functional assays of tolerance. We report here that CD4+ T cells, but not CD8+ T cells, were sufficient to mediate the loss of donor chimerism. In all recipients in which allogeneic chimerism became undetectable, there was a simultaneous loss of donor-specific transplantation tolerance.

  View details for Web of Science ID A1993LK58900033

  View details for PubMedID 8100092

• CHARACTERIZATION OF MATURATION AND FUNCTION OF NATURAL-KILLER-CELLS IN XENOGENEIC (RAT -] MOUSE) BONE-MARROW CHIMERAS - EVIDENCE THAT RAT NK CELLS ARE PRESENT AND FUNCTIONAL IN A XENOGENEIC ENVIRONMENT TRANSPLANTATION Vandenbrink, M. R., French, S. W., Beck, T. P., HRONAKES, M. L., Wren, S. M., Ildstad, S. T. 1993; 55 (2): 355-361

  Abstract

  Reconstitution of B10 recipient mice, conditioned with total body irradiation (950 rads), with 40 x 10(6) untreated F344 or WF rat bone marrow cells results in stable rat stem-cell engraftment with multilineage lymphohematopoietic chimerism. We have now characterized NK cell generation, maturation, and function in fully xenogeneic chimeras (WF rat-->B10 mouse; F344-->B10 mouse). Early during xenogeneic reconstitution, rat-derived NK cells predominated in splenic lymphoid tissue, composing 14-18% of total cells at week 1 and increasing to 35.6-59.9% of total cells at week 2. By week 6, levels of rat NK cells had decreased and stabilized to that expected for normal rat (9-14.2%). The NK chimerism was reliably stable for up to 7 months following reconstitution. Most importantly, rat-derived NK cells were functional in both YAC tumor cytolysis and ADCC assays, suggesting that the xenogeneic mouse host environment was sufficient to support the generation, maturation, and function of rat-derived NK cells.

  View details for Web of Science ID A1993KN01500024

  View details for PubMedID 8434388

• XENOREACTIVITY IN MOUSE PLUS RAT-]MOUSE CHIMERAS JEAN HAMBURGER MEMORIAL CONGRESS / 14TH INTERNATIONAL CONGRESS OF THE TRANSPLANTATION SOC CONRAD, B. G., Wren, S. M., Thai, N. L., Wang, S. C., Ricordi, C., Fung, J. J., PERRY, F. E., Ildstad, S. T. ELSEVIER SCIENCE INC. 1993: 455–56

  View details for Web of Science ID A1993KN62100177

  View details for PubMedID 8438377

• SUBLETHAL IRRADIATION - A NONLETHAL METHOD TO ACHIEVE CROSS-SPECIES CHIMERISM (RAT-]MOUSE) TRANSPLANTATION PROCEEDINGS ABOUELEZZ, A. Y., Wren, S. M., Kaufman, C. L., Ricordi, C., Haluszczak, C., Ildstad, S. T. 1992; 24 (6): 2866-2867

  View details for Web of Science ID A1992KC41300224

  View details for PubMedID 1465976

• PREFERENTIAL DEVELOPMENT OF NKR-P1-EXPRESSING CELLS IN THE SPLEEN VERSUS THYMUS AND BONE-MARROW OF FULLY XENOGENEIC (RAT-]MOUSE) CHIMERAS TRANSPLANTATION PROCEEDINGS Kaufman, C. L., Chambers, W. H., Wren, S. M., ABOUELEZZ, A. Y., Ildstad, S. T. 1992; 24 (6): 2887-2888

  View details for Web of Science ID A1992KC41300233

  View details for PubMedID 1465984

• THE REQUIREMENT FOR ALLOGENEIC CHIMERISM FOR 2ND TRANSFER OF TOLERANCE FROM MIXED ALLOGENEIC CHIMERAS (A + B -] A) TO SECONDARY RECIPIENTS TRANSPLANTATION Wren, S. M., HRONAKES, M. L., Ildstad, S. T. 1992; 54 (6): 1031-1040

  Abstract

  We have applied the model of mixed allogeneic chimerism (A+B-->A), in which stem cells from both allogeneic and syngeneic donor engraft, to determine the in vivo cellular requirements for transfer of tolerance from mixed chimeras to secondary recipients. Using two approaches, we have demonstrated that the persistence of donor-specific transplantation tolerance is dependent on the presence of bone-marrow-derived cells. When untreated bone marrow from mixed chimeras was transferred to irradiated secondary recipient mice, most of the secondary recipients were rescued, but only 48% were demonstrably chimeric. This pattern of repopulation, therefore, allowed us to examine whether chimerism was required to maintain transplantation tolerance. In all of our studies, the presence of allogeneic chimerism was required for successful transfer of tolerance from mixed allogeneic chimeras to irradiated secondary recipients. Only those secondary recipients which repopulated with demonstrable allogeneic chimerism exhibited in vivo and in vitro evidence for transfer of donor-specific transplantation tolerance. These results were confirmed by using transfer of bone marrow from mixed chimeras depleted of allogeneic class I elements. In an attempt to identify a putative population of suppressor cells, second transfer of splenic lymphoid cells from mixed allogeneic chimeras, containing approximately 6 times more T-lymphocytes that were functionally tolerant to donor alloantigens, was also performed with similar results. These data suggest that the in vivo maintenance of tolerance to MHC transplantation alloantigens requires persistence of donor bone marrow-derived alloantigens.

  View details for Web of Science ID A1992KD06200017

  View details for PubMedID 1465769

• EVIDENCE THAT INDEFINITE SURVIVAL OF SMALL-BOWEL ALLOGRAFTS ACHIEVED BY A BRIEF COURSE OF CYCLOSPORINE OR FK506 IS NOT DUE TO SYSTEMIC HYPORESPONSIVENESS TRANSPLANTATION Langrehr, J. M., Hoffman, R. A., Demetris, A. J., Lee, K. K., Neuhaus, P., Wren, S. M., Ildstad, S. T., Schraut, W. H. 1992; 54 (3): 505-510

  Abstract

  The immunological status of Lewis (LEW) recipients of indefinitely surviving (greater than 400 days) orthotopic Brown-Norway (BN) small bowel allografts was investigated 1 to 1 1/2 years after cessation of immunosuppressive therapy with either cyclosporine or FK506 and compared with recipients of syngeneic grafts. A normal proliferative response (as measured by a mixed lymphocyte culture) of recipient peripheral lymph node lymphocytes in response to the donor-specific (BN) and the third-party (ACI) antigen, was observed in all experimental groups. Cytolytic T cell generation (as measured by a standard 51Cr-release cytotoxicity assay) in response to the donor-specific (BN) and the third-party (ACI) antigen was observed also in all groups. A FACS analysis of allograft-recipient splenocytes showed no evidence for systemic lymphoid chimerism. BN or ACI skin grafts transplanted onto recipients of allogeneic and syngeneic small bowel grafts were rejected completely in 12-17 days, while the intestinal grafts remained functional. Immunohistologic evaluation of the allografts, using anti-BN class I and anti-Lewis class II monoclonal antibodies showed anti-BN staining on the epithelial and endothelial structures, whereas the mononuclear cells in the lamina propria stained positively with the anti-LEW monoclonal antibody. However, lymphoid depletion and scarring of Peyer's patches and mesenteric lymph nodes as well as focal obliterative mesenteric arteriopathy, indicative of an indolent chronic rejection, were observed. These data demonstrate that recipients of indefinitely surviving small bowel allografts remain immune competent and do not retain the intestinal graft on the basis of specific hyporesponsiveness to the donor antigens.

  View details for Web of Science ID A1992JP01800022

  View details for PubMedID 1384185

• LONG-TERM SURVIVAL OF DONOR-SPECIFIC PANCREATIC-ISLET XENOGRAFTS IN FULLY XENOGENEIC CHIMERAS TRANSPLANTATION PROCEEDINGS Zeng, Y., Ildstad, S. T., Wren, S. M., Rilo, H. L., BEREITER, D. R., CARROLL, P. B., Tzakis, A. G., Starzl, T. E., Ricordi, C. 1992; 24 (3): 985-985

  View details for Web of Science ID A1992HY79500106

  View details for PubMedID 1604698

  View details for PubMedCentralID PMC2957115

• T-CELL MITOGENIC RESPONSES IN FULLY XENOGENEIC CHIMERAS (WF RAT--]-B10 MOUSE) ARE RESTORED BY BLOCKING THE L-ARGININE-DEPENDENT NITRIC-OXIDE PATHWAY 1ST INTERNATIONAL CONGRESS ON XENOTRANSPLANTATION Wren, S. M., Hoffman, R. A., Billiar, T. R., ABOUELEZZ, A., HRONAKES, M. L., Ildstad, S. T. ELSEVIER SCIENCE INC. 1992: 499–500

  View details for Web of Science ID A1992HN85700033

  View details for PubMedID 1566404

• EVIDENCE FOR THYMIC MATURATION OF BOTH RAT AND MOUSE T-CELLS IN MIXED XENOGENEIC CHIMERAS (B10 MOUSE + F344 RAT--]-B10 MOUSE) 1ST INTERNATIONAL CONGRESS ON XENOTRANSPLANTATION ABOUELEZZ, A. Y., Schuchert, M. J., Wren, S. M., HRONAKES, M. L., Beck, T. P., Ildstad, S. T. ELSEVIER SCIENCE INC. 1992: 501–2

  View details for Web of Science ID A1992HN85700034

  View details for PubMedID 1348886

• MIXED XENOGENEIC CHIMERAS (RAT PLUS MOUSE TO MOUSE) - EVIDENCE OF RAT STEM-CELL ENGRAFTMENT, STRAIN-SPECIFIC TRANSPLANTATION TOLERANCE, AND SKIN-SPECIFIC ANTIGENS TRANSPLANTATION Ildstad, S. T., Boggs, S. S., Vecchini, F., Wren, S. M., HRONAKES, M. L., Johnson, P. C., Vandenbrink, M. R. 1992; 53 (4): 815-822

  Abstract

  We report the induction of stable and reliably detectable mixed xenogeneic chimerism through the coadministration of a mixture of untreated rat bone marrow plus T cell-depleted mouse bone marrow into B10 recipients conditioned with total body irradiation (TCD B10 mouse + untreated F344 rat----B10 mouse). Recipients repopulated as true mixed lymphopoietic chimeras, with from 1-21.6% rat-derived lymphoid cells in peripheral blood and splenic lymphoid tissue. Production of rat platelets was also demonstrated. Rat platelet and lymphoid chimerism was reliably detectable in chimeras from 1 to 7 months following reconstitution, suggesting engraftment of the rat bone marrow stem cell. Production of each stem cell-derived lineage appeared to be under independent regulation since a significantly greater proportion of platelets were rat-derived (24-81%) than were lymphocytes (1-21.6% rat), while erythrocytes were preferentially syngeneic (less than 2% rat). The tolerance induced by this model was highly donor strain-specific: donor-specific rat and mouse skin grafts were accepted while MHC-disparate third-party mouse (C3H; H-2k) and rat (Wistar Furth; Rt1Au) skin grafts were promptly rejected. Although specifically prolonged xenogeneic donor rat skin grafts underwent a slow chronic rejection, and some totally disappeared. In spite of this, chimeras retained their lymphoid chimerism, suggesting the presence of skin-specific antigens. This model for mixed xenogeneic chimerism with reliably detectable rat lymphoid cells may provide a model to study the existence of tissue-specific antigens across a species barrier, as well as mechanisms responsible for the induction and maintenance of this strain-specific transplantation tolerance.

  View details for Web of Science ID A1992HP30600022

  View details for PubMedID 1566347

• CROSS-SPECIES TRANSPLANTATION - NK CELL NUMBER AND FUNCTION ARE NORMAL IN FULLY XENOGENEIC CHIMERAS (RAT-]MOUSE) 22ND ANNUAL MEETING OF THE AMERICAN PEDIATRIC SURGICAL ASSOC French, S. N., Wren, S. M., HRONAKES, M. L., Ildstad, S. T. W B SAUNDERS CO-ELSEVIER INC. 1992: 307–11

  Abstract

  When untreated F344 rat bone marrow is transplanted into B10 mouse recipients conditioned with total body irradiation, stable fully xenogeneic chimerism (rat----mouse) results. Chimeras are specifically tolerant to the donor strain of rat, survival is excellent (greater than 80% at 8 months), and all stem-cell-derived lineages are produced by the rat stem cell. We have previously demonstrated normal function of T-lymphocytes in these chimeras, but have not examined the immune function of natural killer (NK) cells present. Because NK cells play a critical role in immune surveillance, absence of function could result in a serious immunodeficiency state. We present data here to suggest that rat NK cells that have developed in a mouse stromal environment are normal in function as well as number. In all fully xenogeneic chimeras tested from 8 weeks to 8 months following bone marrow transplantation, NK cells were present at a normal level (10% to 16%). NK cells function in these chimeras, as tested by spontaneous lysis of YAC tumor cell targets, was normal or superior to normal F344 rat and B10 mouse NK cells.

  View details for Web of Science ID A1992HJ05700007

  View details for PubMedID 1501002

• CROSS-SPECIES TRANSPLANTATION TOLERANCE - RAT BONE-MARROW DERIVED CELLS CAN CONTRIBUTE TO THE LIGAND FOR NEGATIVE SELECTION OF MOUSE T-CELL RECEPTOR-V-BETA IN CHIMERAS TOLERANT TO XENOGENEIC ANTIGENS (MOUSE + RAT -] MOUSE) JOURNAL OF EXPERIMENTAL MEDICINE Ildstad, S. T., Vacchio, M. S., Markus, P. M., HRONAKES, M. L., Wren, S. M., Hodes, R. J. 1992; 175 (1): 147-155

  Abstract

  Mixed xenogeneic bone marrow reconstitution (mouse + rat----mouse) results in stable mixed lymphopoietic chimerism (1-48% rat), long-term survival, and the induction of stable functional donor-specific transplantation tolerance to xenoantigens in vivo. To examine the role of negative selection of potentially xenoreactive T lymphocytes during tolerance induction across a species barrier, mixed xenogeneic chimeras (mouse + rat----mouse) were prepared and analyzed using a mixture of mouse and rat bone marrow cells for relative T cell receptor (TCR)-V beta expression on mouse T cells. In mixed xenogeneic chimeras (B10 mouse + rat----B10 mouse), T cell maturation proceeded normally in the presence of rat bone marrow-derived elements, and functional donor-specific tolerance to rat xenoantigens was present when assessed by mixed lymphocyte reactivity in vitro. V beta 5, which is expressed at high (undeleted) levels in normal B10 mice, was consistently deleted in B10 recipients of Wistar Furth (WF), but not F344 rat bone marrow, whereas the coadministration of either F344 rat or WF rat bone marrow with B10 mouse bone marrow cells resulted in a significant decrease in expression of TCR-V beta 11. Taken together, these data demonstrate for the first time that rat bone marrow-derived cells can contribute in a strain-specific manner to the ligand for negative selection of specific mouse TCR-V beta during tolerance induction across a species barrier.

  View details for Web of Science ID A1992GY43600018

  View details for PubMedID 1530958

  View details for PubMedCentralID PMC2119098

• CROSS-SPECIES BONE-MARROW TRANSPLANTATION - EVIDENCE FOR RECOGNITION OF SKIN-SPECIFIC ANTIGENS ACROSS A SPECIES BARRIER (RAT-]MOUSE) JOURNAL OF SURGICAL RESEARCH Ildstad, S. T., Wren, S. M., HRONAKES, M. L. 1991; 51 (5): 372-376

  Abstract

  We have developed a model to study cross-species bone marrow transplantation and the associated donor-specific transplantation tolerance induced using fully xenogeneic chimeras. Reconstitution of lethally irradiated B10 mice with untreated F344 rat bone marrow cells results in fully xenogeneic chimerism (F344 rat----B10 mouse). Survival of recipients is excellent (greater than 80% at 100 days) and stable rat lymphoid and multilineage chimerism are present throughout the life of the chimeras. Recipients are specifically tolerant to donor-type skin xenografts yet are competent to reject major histocompatibility complex (MHC)--disparate third party strain rat xenografts. Although prolonged, donor-specific skin xenografts underwent chronic rejection which had its onset at approximately 40 days following skin graft placement. We have now examined these chimeras by serial flow cytometry typing to determine whether this is due to skin-specific antigens expressed on skin, but not on the bone marrow elements to which the chimeras were rendered tolerant. In all animals examined, lymphopoietic chimerism persisted unchanged even after the onset of inflammation in the grafts, suggesting the presence of skin specific antigens. This model may provide a method to study tissue and organ specific antigens recognized across a species barrier.

  View details for Web of Science ID A1991GK45000003

  View details for PubMedID 1758170

• KINETICS OF EARLY T-CELL REPOPULATION IN FULLY XENOGENEIC CHIMERAS (F344 RAT-]B10 MOUSE) - EVIDENCE FOR RAT T-CELL MATURATION IN A XENOGENEIC MOUSE THYMUS 52ND ANNUAL MEETING OF THE SOC OF UNIVERSITY SURGEONS Wren, S. M., HRONAKES, M. L., Ildstad, S. T. MOSBY-YEAR BOOK INC. 1991: 238–46

  Abstract

  We recently reported the model of fully xenogeneic chimerism achieved by transplantation of rat bone marrow into mouse recipients (F344 rat----B10 mouse), resulting in stable long-term rat lymphoid chimerism. We have now extended this model to examine whether developing precursor rat T cells from rat bone marrow stem cells can undergo normal differentiation in mature lymphocytes under the influence of a xenogeneic mouse thymus. We examined thymic and splenic lymphoid cells from fully xenogeneic chimeras starting 1 week after bone marrow transplantation to characterize early T-cell repopulation and phenotype. Our data suggest that developing rat precursor T cells are able to undergo normal differentiation in the mouse thymus. The first precursor T cells appeared 2 weeks after reconstitution and by week 10 accounted for more than 90% of thymocytes present in the chimeras. In chimeras, developing rat T lymphocytes in the mouse thymus exhibited an immature pattern (Thy 1.1+, alpha beta-TCRdull, CD4+ plus CD8+) when analyzed by flow cytometry. This pattern was similar to a normal rat. In contrast, splenic T-lymphoid cells showed a mature rat phenotype (Thy 1.1-, alpha beta-TCRhi, CD4+ or CD8+), again similar to a normal rat. This development began 2 weeks after bone marrow transplantation, and both thymus and spleen from chimeras exhibited "normal" rat T-cell staining profiles by 10 weeks after reconstitution. Overall, these data indicate that developing rat T cells are capable of undergoing normal maturation in a xenogeneic mouse thymus of tolerant animals.

  View details for Web of Science ID A1991FZ62800016

  View details for PubMedID 1858033

• CROSS-SPECIES BONE-MARROW TRANSPLANTATION - EVIDENCE FOR TOLERANCE INDUCTION, STEM-CELL ENGRAFTMENT, AND MATURATION OF LYMPHOCYTES-T IN A XENOGENEIC STROMAL ENVIRONMENT (RAT-]MOUSE) JOURNAL OF EXPERIMENTAL MEDICINE Ildstad, S. T., Wren, S. M., Boggs, S. S., HRONAKES, M. L., Vecchini, F., Vandenbrink, M. R. 1991; 174 (2): 467-478

  Abstract

  Transplantation of untreated F344 rat bone marrow into irradiated B10 mouse recipients (non-TCD F344----B10) to produce fully xenogeneic chimeras resulted in stable xenogeneic lymphoid chimerism, ranging from 82% to 97% rat. Survival of animals was excellent, without evidence for GVH disease. The specificity of tolerance which resulted was highly donor-specific; MHC disparate third party mouse and rat skin grafts were promptly rejected while donor-specific F344 grafts were significantly prolonged (MST greater than 130 days). Multi-lineage rat stem cell-derived progeny including lymphoid cells (T- and B-lymphocytes), myeloid cells, erythrocytes, platelets, and natural killer (NK) cells were present in the fully xenogenic chimeras up to 7 months after bone marrow transplantation. Immature rat T-lymphocytes matured and acquired the alpha/beta T-cell receptor in the thymus of chimeras in a pattern similar to normal rat controls, suggesting that immature T-lymphocytes of rat origin could interact with the murine xenogeneic thymic stroma to undergo normal maturation and differentiation. This model may be useful to study the mechanisms responsible for the induction and maintenance of donor-specific transplantation tolerance across a species barrier.

  View details for Web of Science ID A1991FY50200018

  View details for PubMedID 1856629

  View details for PubMedCentralID PMC2118904

• MIXED ALLOGENEIC RECONSTITUTION (A+B-]A) TO INDUCE DONOR-SPECIFIC TRANSPLANTATION TOLERANCE - PERMANENT ACCEPTANCE OF A SIMULTANEOUS DONOR SKIN-GRAFT TRANSPLANTATION Ildstad, S. T., Wren, S. M., Oh, E., HRONAKES, M. L. 1991; 51 (6): 1262-1267

  Abstract

  Mixed allogeneic reconstitution, in which a mixture of T-cell-depleted bone marrow of syngeneic host and allogeneic donor type is transplanted into a lethally irradiated recipient (A+B----A), results in mixed lymphopoietic chimerism with engraftment of a mixture of both host and donor bone marrow elements. Recipients are specifically tolerant to donor both in vitro and in vivo. Donor-specific skin grafts survive indefinitely when they are placed after full bone marrow repopulation at 28 days, while third-party grafts are rapidly rejected. To determine whether a delay of a month or more for full bone marrow repopulation is required before a donor-specific graft can be placed, we have now examined whether tolerance induction can be achieved if a graft is placed at the time of bone marrow transplantation. Permanent acceptance of donor-specific B10.BR skin grafts occurred when mixed allogeneic chimerism (B10+B10.BR----B10) was induced and a simultaneous allogeneic donor graft placed. In vitro, mixed reconstituted recipients were specifically tolerant to the B10.BR donor lymphoid cells but fully reactive to MHC-disparate third-party (BALB/c; H-2dd) when assessed by mixed lymphocyte reaction (MLR) and cell-mediated lympholysis (CML) assays. These data therefore indicate that a donor-specific graft placed at the time of mixed allogeneic reconstitution is permanently accepted without rejection. To determine whether an allogeneic skin graft alone without allogeneic bone marrow would be sufficient to induce tolerance, syngeneic reconstitution (B10----B10) was carried out, and a simultaneous B10.BR allogeneic skin graft placed. Although skin grafts were prolonged in all recipients, all grafts rejected when full lymphopoietic repopulation occurred at 28 days. Taken together, these data suggest that allogeneic donor bone marrow elements are required for the induction and maintenance of donor-specific transplantation tolerance and that allogeneic skin grafts alone are not sufficient for tolerance induction.

  View details for Web of Science ID A1991FR73600022

  View details for PubMedID 1828637

• MIXED CHIMERISM TO INDUCE TOLERANCE FOR SOLID ORGAN-TRANSPLANTATION 21ST ANNUAL MEETING OF THE AMERICAN PEDIATRIC SURGICAL ASSOC Wren, S. M., Nalesnik, M., HRONAKES, M. L., Oh, E., Ildstad, S. T. W B SAUNDERS CO-ELSEVIER INC. 1991: 439–43

  Abstract

  Chimerism, or the coexistence of tissue elements from more than one genetically different strain or species in an organism, is the only experimental state that results in the induction of donor-specific transplantation tolerance. Transplantation of a mixture of T-cell-depleted syngeneic (host-type) plus T-cell-depleted allogeneic (donor) bone marrow into a normal adult recipient mouse (A + B----A) results in mixed allogeneic chimerism. Recipient mice exhibit donor-specific transplantation tolerance, yet have full immunocompetence to recognize and respond to third-party transplantation antigens. After complete hematolymphopoietic repopulation at 28 days, animals accept a donor-specific skin graft but reject major histocompatibility complex (MHC) locus-disparate third-party grafts. We now report that permanent graft acceptance can also be achieved when the graft is placed at the time of bone marrow transplantation. Histologically, grafts were viable and had only minimal inflammatory changes. This model may have potential future clinical application for the induction of donor-specific transplantation tolerance.

  View details for Web of Science ID A1991FF05500014

  View details for PubMedID 2056405

• SUCCESSFUL TRANSFER OF DONOR-SPECIFIC TRANSPLANTATION TOLERANCE BY ADOPTIVE TRANSFER OF FULLY ALLOGENEIC CHIMERIC BONE-MARROW 13TH INTERNATIONAL CONGRESS OF THE TRANSPLANTATION SOC Wren, S. M., HRONAKES, M. L., Ildstad, S. T. ELSEVIER SCIENCE INC. 1991: 735–36

  View details for Web of Science ID A1991EV39000289

  View details for PubMedID 1990670

• CROSS-SPECIES MIXED CHIMERISM (MOUSE + RAT -] MOUSE) - FACILITATED ENGRAFTMENT OF RAT STEM-CELLS WITH UNTREATED RAT BONE-MARROW 13TH INTERNATIONAL CONGRESS OF THE TRANSPLANTATION SOC Vandenbrink, M. R., Wren, S. M., French, S. W., HRONAKES, M. L., Ildstad, S. T. ELSEVIER SCIENCE INC. 1991: 807–8

  View details for Web of Science ID A1991EV39000322

  View details for PubMedID 1671307

• EFFECT OF SELECTIVE T-CELL DEPLETIONS IN MIXED XENOGENEIC RECONSTITUTION ON SPECIFIC HYPOREACTIVITY TO TRANSPLANTATION ACROSS A SPECIES BARRIER TRANSPLANTATION Ildstad, S. T., Wren, S. M., Stephany, D., Sachs, D. H. 1986; 41 (3): 372-376

  Abstract

  We have recently reported the induction of long-term specific hyporeactivity to transplantation across a species barrier (rat----mouse) through reconstitution of irradiated recipients with a mixture of T-cell-depleted host-type C57BL/10Sn (B10) bone marrow plus T-cell-depleted F344 rat bone marrow (B10+F344----B10) (1). We report here the influence of selective T cell depletions of host-type and/or donor-type bone marrow on induction of such hyporeactivity. Mice that received mixed bone marrow inocula in which the syngeneic marrow had been T-cell-depleted, whether or not the xenogeneic donor marrow had been treated, showed specific prolongation of F344 donor-type skin grafts. In contrast, F344 rat skin grafts were promptly rejected by animals that had received mixed bone marrow inocula in which the syngeneic component had not been T-cell-depleted. Serologic reactivity against F344 lymphocyte cell surface antigens also differed among the four groups; animals that had received untreated syngeneic bone marrow demonstrated high levels of reactivity to F344 target cells, while animals reconstituted with mixed inocula in which the syngeneic component had been T-cell-depleted exhibited low levels, if any, of serologic reactivity against F344 splenocytes. This model for mixed xenogeneic reconstitution may be helpful to define the conditions required for induction of transplantation tolerance across a species barrier.

  View details for Web of Science ID A1986A511800017

  View details for PubMedID 3513395

• EFFECT OF SELECTIVE T-CELL DEPLETION OF HOST AND OR DONOR BONE-MARROW ON LYMPHOPOIETIC REPOPULATION, TOLERANCE, AND GRAFT-VS-HOST DISEASE IN MIXED ALLOGENEIC CHIMERAS (B-10 + B10.D2-]B10) JOURNAL OF IMMUNOLOGY Ildstad, S. T., Wren, S. M., Bluestone, J. A., BARBIERI, S. A., Stephany, D., Sachs, D. H. 1986; 136 (1): 28-33

  Abstract

  Reconstitution of lethally irradiated mice with a mixture of T cell-depleted syngeneic plus T cell-depleted allogeneic bone marrow (B10 + B10.D2----B10) leads to the induction of mixed lymphopoietic chimerism, excellent survivals, specific in vivo transplantation tolerance to subsequent donor strain skin grafts, and specific in vitro unresponsiveness to allogeneic donor lymphoid elements as assessed by mixed lymphocyte reaction (MLR) proliferative and cell-mediated lympholysis (CML) cytotoxicity assays. When B10 recipient mice received mixed marrow inocula in which the syngeneic component had not been T cell depleted, whether or not the allogeneic donor marrow was treated, they repopulated exclusively with host-type cells, promptly rejected donor-type skin allografts, and were reactive in vitro to the allogeneic donor by CML and MLR assays. In contrast, T cell depletion of the syngeneic component of the mixed marrow inocula resulted in specific acceptance of allogeneic donor strain skin grafts, whether or not the allogeneic bone marrow was T cell depleted. Such animals were specifically unreactive to allogeneic donor lymphoid elements in vitro by CML and MLR, but were reactive to third party. When both the syngeneic and allogeneic marrow were T cell depleted, variable percentages of host- and donor-type lymphoid elements were detected in the mixed reconstituted host. When only the syngeneic bone marrow was T cell depleted, animals repopulated exclusively with donor-type cells. Although these animals had detectable in vitro anti-host (B10) reactivity by CML and MLR and reconstituted as fully allogeneic chimeras, they exhibited excellent survival and had no in vivo evidence for graft-vs-host disease. In addition, experiments in which untreated donor spleen cells were added to the inocula in this last group suggest that the presence of T cell-depleted syngeneic bone marrow cells diminishes graft-vs-host disease and the mortality from it. This system may be helpful as a model for the study of alloresistance and for the identification of syngeneic cell phenotypes, which when present prevent engraftment of allogeneic marrow.

  View details for Web of Science ID A1986AWM4600006

  View details for PubMedID 2933464

• CHARACTERIZATION OF MIXED ALLOGENEIC CHIMERAS - IMMUNOCOMPETENCE, INVITRO REACTIVITY, AND GENETIC SPECIFICITY OF TOLERANCE JOURNAL OF EXPERIMENTAL MEDICINE Ildstad, S. T., Wren, S. M., Bluestone, J. A., BARBIERI, S. A., Sachs, D. H. 1985; 162 (1): 231-244

  Abstract

  Mixed allogeneically reconstituted mice (B10 + B10.D2----B10) that specifically accept B10.D2 tail skin allografts were examined for in vivo and in vitro immunocompetence, patterns of hematopoietic repopulation, and in vitro reactivity. In vitro, mixed allogeneic chimeras (B10 + B10.D2----B10) manifested specific tolerance in mixed lymphocyte reactions and cell-mediated lympholysis to B10 and B10.D2 splenocytes, with normal responses to third-party (B10.BR) cells. Such chimeras were immunocompetent in B cell and helper T cell responses, as assessed by their primary plaque forming cell responses to in vivo sheep red blood cell immunization. This is in contrast to fully allogeneic chimeras, which responded less well. In addition, survival of the mixed allogeneic chimeras in a conventional animal facility was superior to that of fully allogeneic chimeras, and similar to syngeneically reconstituted (B10----B10) mice. Specific tolerance to skin grafts, degree of allogeneic engraftment, and persistence of chimerism was also assessed in a noncongenic mixed allogeneic combination (B10 + C3H----B10). Such animals manifested specific hyporeactivity to C3H skin allografts, but eventual chronic rejection of the grafts occurred in spite of stable and persistent mixed chimerism. MHC-congenic (B10.BR) skin grafts were accepted indefinitely in the same animals, suggesting that skin-specific non-major histocompatibility complex antigens were responsible for rejection of the C3H skin allografts.

  View details for Web of Science ID A1985ALW4900017

  View details for PubMedID 3159825

  View details for PubMedCentralID PMC2187693

• INVIVO AND INVITRO CHARACTERIZATION OF SPECIFIC HYPOREACTIVITY TO SKIN XENOGRAFTS IN MIXED XENOGENEICALLY RECONSTITUTED MICE (B10+F344RAT-]B10) JOURNAL OF EXPERIMENTAL MEDICINE Ildstad, S. T., Wren, S. M., Sharrow, S. O., Stephany, D., Sachs, D. H. 1984; 160 (6): 1820-1835

  Abstract

  Mixed xenogeneically reconstituted mice (F344 rat + C57BL/10Sn----C57BL/10Sn), which specifically retain F344 tail skin xenografts, were studied for the specificity of such hyporeactivity and for in vitro reactivity and immunocompetence. Survival of mixed reconstituted animals was excellent, without evidence for graft vs. host disease. Donor-type tail skin grafts were specifically prolonged (mean survival time = 80 d) in comparison with normal controls and syngeneically reconstituted animals. In vitro, such animals manifested specific hyporeactivity by mixed lymphocyte reaction and cell-mediated lympholysis to F344 rat and B10 cells, with normal response to third-party rat (Wistar-Furth) and mouse (B10.BR). Examination of lymphoid tissues with a fluorescence-activated cell sorter revealed low levels, if any, of donor-type cells detectable. This system offers a model for investigation of xenogeneic transplantation tolerance.

  View details for Web of Science ID A1984TX70100015

  View details for PubMedID 6239902

  View details for PubMedCentralID PMC2187530

• INHIBITION OF THE GRAFT-VERSUS-HOST RESPONSE BY BCGCW-INDUCED SUPPRESSOR CELLS OR PROSTAGLANDIN-E1 CELLULAR IMMUNOLOGY Wren, S. M., Wepsic, H. T., Larson, C. H., DESILVA, M. A., Mizushima, Y. 1983; 76 (2): 361-371

  Abstract

  Immunization of C57BL/6 mice with BCGcw stimulated a population of "suppressor cells" which had a decreased capacity to induce the graft-versus-host response. The graft-versus-host response was quantitated using the Simonsen splenomegaly assay. F1 mice (C57BL/6 X CBA) were inoculated intraperitoneally with 1 X 10(8) parental (C57BL/6) or (CBA) spleen cells. The F1 mice were sacrificed 13 days later and the resulting splenomegaly was 3-4 times the normal amount. F1 mice which were injected with parental BCGcw-primed C57BL/6 spleen cells had a 50% inhibition of splenomegaly, whereas BCGcw-primed CBA spleen cells (a strain which does not develop suppressor cells) did not show this inhibition. In vitro results also confirmed that only C57BL/6 mice and not CBA mice developed suppressor cells after BCGcw immunization. A second study showed that X-irradiated (1000 R) BCGcw-primed "suppressor cells" could inhibit splenomegaly caused by the inoculation of normal parental C57BL/6 cells into F1 mice. The mechanism by which BCGcw-primed "suppressor cells" caused this inhibition of splenomegaly was delineated and found to be dependent upon the secretion of prostaglandin (PGE-1). Indomethacin and aspirin, potent inhibitors of prostaglandin synthesis, blocked the activity of C57BL/6 BCGcw "suppressor cells" and splenomegaly resulted. Systemic administration of the prostaglandin (15S)-15-methyl PGE-1 reduced splenomegaly approximately 50% in F1 mice which were injected with C57BL/6 or CBA cells. These results indicated that immunization with BCGcw stimulated a population of "suppressor cells" which could cause a decrease in graft-versus-host response and that the secretion of prostaglandin was responsible for this inhibition.

  View details for Web of Science ID A1983QM43500016

  View details for PubMedID 6220811

• SUPPRESSOR CELLS INDUCED BY BCG CELL-WALLS (BCGCW) HAVE A DECREASED CAPACITY TO INDUCE GRAFT VS HOST-DISEASE WEPSIC, H. T., WREN, S., DESILVA, M. A. AMER ASSOC CANCER RESEARCH. 1982: 246

  View details for Web of Science ID A1982NT42100969