George C Velmahos

Harvard Medical School, Boston, Massachusetts, United States

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Publications (442)1289.87 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Heart rate complexity, commonly described as a "new vital sign," has shown promise in predicting injury severity, but its use in clinical practice is not yet widely adopted. We previously demonstrated the ability of this noninvasive technology to predict lifesaving interventions (LSIs) in trauma patients. This study was conducted to prospectively evaluate the utility of real-time, automated, noninvasive, instantaneous sample entropy (SampEn) analysis to predict the need for an LSI in a trauma alert population presenting with normal vital signs. Prospective enrollment of patients who met criteria for trauma team activation and presented with normal vital signs was conducted at a level I trauma center. High-fidelity electrocardiogram recording was used to calculate SampEn and SD of the normal-to-normal R-R interval (SDNN) continuously in real time for 2 hours with a portable, handheld device. Patients who received an LSI were compared to patients without any intervention (non-LSI). Multivariable analysis was performed to control for differences between the groups. Treating clinicians were blinded to results. Of 129 patients enrolled, 38 (29%) received 136 LSIs within 24 hours of hospital arrival. Initial systolic blood pressure was similar in both groups. Lifesaving intervention patients had a lower Glasgow Coma Scale. The mean SampEn on presentation was 0.7 (0.4-1.2) in the LSI group compared to 1.5 (1.1-2.0) in the non-LSI group (P < .0001). The area under the curve with initial SampEn alone was 0.73 (95% confidence interval [CI], 0.64-0.81) and increased to 0.93 (95% CI, 0.89-0.98) after adding sedation to the model. Sample entropy of less than 0.8 yields sensitivity, specificity, negative predictive value, and positive predictive value of 58%, 86%, 82%, and 65%, respectively, with an overall accuracy of 76% for predicting an LSI. SD of the normal-to-normal R-R interval had no predictive value. In trauma patients with normal presenting vital signs, decreased SampEn is an independent predictor of the need for LSI. Real-time SampEn analysis may be a useful adjunct to standard vital signs monitoring. Adoption of real-time, instantaneous SampEn monitoring for trauma patients, especially in resource-constrained environments, should be considered. Copyright © 2015. Published by Elsevier Inc.
    Journal of critical care 03/2015; DOI:10.1016/j.jcrc.2015.03.018 · 2.19 Impact Factor
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    ABSTRACT: Computed tomography angiography (CTA) has been increasingly used in traumatic brain injury (TBI) patients to uncover vascular lesions that might have preceded the trauma and caused the bleed. This study aims to evaluate the usefulness of head CTA in the initial care of blunt TBI patients. We conducted a retrospective case-control analysis of adult TBI patients, admitted to our Level I trauma center from January 1, 2012 to December 31, 2012. The patients were grouped as those with and without a CTA of the head. The primary outcomes included a change in management after the findings of head CTA and secondary outcomes included rate of admission to the ICU, ICU length of stay, hospital length of stay, discharge disposition, and mortality. Six hundred adult patients had blunt TBI and underwent head CT as a part of their evaluation. Of these 600 patients, 132 (22%) underwent head CTA in addition to CT. Only one patient had altered management after the CTA results; the patient had a diagnostic angiogram that was negative. Ninety-eight patients did not have any additional findings on CTA. Of the remaining 33 patients with additional CTA findings, 12 had incidental vascular malformations, which showed no acute pathology and were not related to the injury. In the matched comparisons, patients with CTA had a longer hospital stay, higher rate of ICU admission, and longer ICU stay. There was no significant difference in mortality and discharge disposition between the 2 groups. Head CTA is commonly used after blunt TBI but does not alter management and should be abandoned in the absence of clear indications. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.
    Journal of the American College of Surgeons 03/2015; DOI:10.1016/j.jamcollsurg.2015.03.002 · 4.45 Impact Factor
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    ABSTRACT: Graduated driving licensing (GDL) programs phase in driving privileges for teenagers. We aimed to evaluate the effect of the 2007 GDL law on the incidence of total motor vehicle crashes (tMVCs) and fatal motor vehicle crashes (fMVCs) among teenagers in Massachusetts. The Fatality Analysis and Reporting System, the Missouri Census Data Center, and the Massachusetts Department of Transportation databases were all used to create and compare the incidence of tMVCs and fMVCs before (2002-2006) and after (2007-2011) the law enactment. The following three driver age groups were studied: 16 years to 17 years (evaluating the law effect), 18 years to 20 years (evaluating the sustainability of the effect), and 25 years to 29 years (control group). As a sensitivity analysis, we compared the incidence rates per population and per licenses issued. tMVCs decreased following the law for all three age groups (16-17 years, from 7.6 to 4.8 per 1,000 people, p < 0.0001; 18-20 years, from 8.5 to 6.4 per 1,000 people, p < 0.0001; 25-29 years, from 6.2 to 5.2 per 1,000 people, p < 0.0001), but the percentage decrease in tMVC rates was less in the control group (37%, 25%, and 15%, respectively; both p's < 0.0001). The rates of fMVC also decreased in the age groups of 16 years to 17 years (from 14.0 to 8.6 per 100,000 people, p = 0.0006), 18 years to 20 years (from 21.2 to 13.7 per 100,000 people, p < 0.0001), and 25 years to 29 years (from 14.4 to 11.0 per 100,000 people, p < 0.0001). All of these results were confirmed in the sensitivity analyses. The 2007 Massachusetts GDL was associated with a decreased incidence of teenager tMVCs and fMVCs, and the effect was sustainable. This study provides further support to develop, implement, enforce, and maintain GDL programs aimed at preventing MVCs and their related mortality in the young novice driver population. Epidemiologic/prognostic study, level III.
    Journal of Trauma and Acute Care Surgery 02/2015; 78(2):265-271. DOI:10.1097/TA.0000000000000512 · 1.97 Impact Factor
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    ABSTRACT: To date, no studies have reported nationwide adoption of acute care surgery (ACS) or identified structural and/or process variations for the care of emergency general surgery (EGS) patients within such models. We surveyed surgeons responsible for EGS coverage at University Health Systems Consortium hospitals using an eight-page postal/e-mail questionnaire querying respondents on hospital and EGS structure/process measures. Survey responses were analyzed using descriptive statistics, univariate comparisons, and multivariable regression models. Of 319 potential respondents, 258 (81%) completed the surveys. A total of 81 hospitals (31%) had implemented ACS, while 134 (52%) had a traditional general surgeon on-call (GSOC) model. Thirty-eight hospitals (15%) had another model (hybrid). Larger-bed, university-based, teaching hospitals with Level 1 trauma center verification status located in urban areas were more likely to have adopted ACS. In multivariable modeling, hospital type, setting, and trauma center verification predicted ACS implementation. EGS processes of care varied, with 28% of the GSOC hospitals having block time versus 67% of the ACS hospitals (p < 0.0001), 45% of the GSOC hospitals providing ICU [intensive care unit] care to EGS patients in a surgical/trauma ICU versus 93% of the ACS hospitals (p < 0.0001), 5.7 ± 3.2 surgeons sharing call at GSOC hospitals versus 7.9 ± 2.3 surgeons at ACS hospitals (p < 0.0001), and 13% of the GSOC hospitals requiring in-house EGS call versus 75% of the ACS hospitals (p < 0.0001). Among ACS hospitals, there were variations in patient cohorting (EGS patients alone, 25%; EGS + trauma, 21%; EGS + elective, 17%; and EGS + trauma + elective, 30%), data collection (26% had prospective EGS registries), patient hand-offs (56% had attending surgeon presence), and call responsibilities (averaging 4.8 ± 1.3 calls per month, with 60% providing extra call stipend and 40% with no postcall clinical duties). The potential of the ACS on the national crisis in access to EGS care is not fully met. Variations in EGS processes of care among adopters of ACS suggest that standardized criteria for ACS implementation, much like trauma center verification criteria, may be beneficial.
    Journal of Trauma and Acute Care Surgery 01/2015; 78(1):60-8. DOI:10.1097/TA.0000000000000492 · 1.97 Impact Factor
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    ABSTRACT: Excessive crystalloid administration is common and associated with negative outcomes in critically ill trauma patients. Continuous furosemide infusion (CFI) to remove excessive fluid has not been previously described in this population. We hypothesized that a goal-directed CFI is more effective for fluid removal than intermittent bolus injection (IBI) diuresis without excess incidence of hypokalemia or renal failure. CFI cases were prospectively enrolled between November 2011 and August 2012, and matched to historic IBI controls by age, gender, Injury Severity Score (ISS), and net fluid balance (NFB) at diuresis initiation. Paired and unpaired analyses were performed to compare groups. The primary endpoints were net fluid balance, potassium and creatinine levels. Secondary endpoints included intensive care unit (ICU) and hospital length of stay (LOS), ventilator-free days (VFD), and mortality. 55 patients were included, with 19 cases and 36 matched controls. Mean age was 54 years, mean ISS was 32.7, and mean initial NFB was +7.7 L. After one day of diuresis with CFI vs. IBI, net 24 h fluid balance was negative (-0.55 L vs. +0.43 L, P = 0.026) only for the CFI group, and there was no difference in potassium and creatinine levels. Cumulative furosemide dose (59.4mg vs. 25.4mg, P < 0.001) and urine output (4.2 L vs. 2.8 L, P < 0.001) were also significantly increased with CFI vs. IBI. There were no statistically significant differences in ICU LOS, hospital LOS, VFD, or mortality. Compared to IBI, goal-directed diuresis by CFI is more successful in achieving net negative fluid balance in patients with fluid overload with no detrimental side effects on renal function or patient outcome.
    Journal of Emergencies Trauma and Shock 01/2015; 8(1):34-8. DOI:10.4103/0974-2700.150395
  • Haytham M A Kaafarani, George C Velmahos
    Surgery 01/2015; 157(1):6-7. DOI:10.1016/j.surg.2014.10.001 · 3.11 Impact Factor
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    ABSTRACT: Objective: We discuss the strengths of the medical response to the Boston Marathon bombings that led to the excellent outcomes. Potential shortcomings were recognized, and lessons learned will provide a foundation for further improvements applicable to all institutions. Background: Multiple casualty incidents from natural or man-made incidents remain a constant global threat. Adequate preparation and the appropriate alignment of resources with immediate needs remain the key to optimal outcomes. Methods: A collaborative effort among Boston's trauma centers (2 level I adult, 3 combined level I adult/pediatric, 1 freestanding level I pediatric) examined the details and outcomes of the initial response. Each center entered its respective data into a central database (REDCap), and the data were analyzed to determine various prehospital and early in-hospital clinical and logistical parameters that collectively define the citywide medical response to the terrorist attack. Results: A total of 281 people were injured, and 127 patients received care at the participating trauma centers on that day. There were 3 (1%) immediate fatalities at the scene and no in-hospital mortality. A majority of the patients admitted (66.6%) suffered lower extremity soft tissue and bony injuries, and 31 had evidence for exsanguinating hemorrhage, with field tourniquets in place in 26 patients. Of the 75 patients admitted, 54 underwent urgent surgical intervention and 12 (22%) underwent amputation of a lower extremity. Conclusions: Adequate preparation, rapid logistical response, short transport times, immediate access to operating rooms, methodical multidisciplinary care delivery, and good fortune contributed to excellent outcomes.
    Annals of Surgery 12/2014; 260(6):960-6. DOI:10.1097/SLA.0000000000000914 · 7.19 Impact Factor
  • Elie Ramly, Haytham M.A. Kaafarani, George C. Velmahos
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    ABSTRACT: Age-related anatomic, physiologic, and immunologic changes to the pulmonary system, as well as a high prevalence of chronic pulmonary diseases, puts the geriatric patient at an especially high risk for postoperative pulmonary complications. Successful perioperative respiratory care of the geriatric patient relies on careful risk assessment and optimization of pulmonary function and support. The success of such efforts aimed at preventing and/or mitigating pulmonary complications in the geriatric patient depends on a thorough, individualized, yet standardized and evidence-based approach to the care of every patient. Copyright © 2015 Elsevier Inc. All rights reserved.
    Surgical Clinics of North America 11/2014; 95(1). DOI:10.1016/j.suc.2014.09.009 · 1.93 Impact Factor
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    ABSTRACT: Main concern during the practice of selective non-operative management (SNOM) for abdominal stab wounds (SW) and gunshot wounds (GSW) is the potential for harm in patients who fail SNOM and receive a delayed laparotomy (DL). The aim of this study is to determine whether such patients suffer adverse sequelae because of delays in diagnosis and treatment when managed under a structured SNOM protocol. 190 patients underwent laparotomy after an abdominal GSW or SW (5/04-10/12). Patients taken to operation within 120 min of admission were included in the early laparotomy (EL) group (n =153, 80.5 %) and the remaining in the DL group (n =37, 19.5 %). Outcomes included mortality, hospital stay, and postoperative complications. The median time from hospital arrival to operation was 43 min (range: 17-119) for EL patients and 249 min (range: 122-1,545) for DL patients. The average number and type of injuries were similar among the groups. Mortality and negative laparotomy were observed only in the EL group. There was no significant difference in the hospital stay between the groups. The overall complications were higher in the EL group (44.4 vs. 24.3 %, p =0.026). DL was independently associated with a lower likelihood for complications (OR 0.39, 95 % CI 0.16-0.98, p =0.045). Individual review of all DL patients did not reveal an incident in which complications could be directly attributed to the delay. In a structured protocol, patients who fail SNOM and require an operation are recognized and treated promptly. The delay in operation does not cause unnecessary morbidity or mortality.
    World Journal of Surgery 10/2014; 39(2). DOI:10.1007/s00268-014-2813-7 · 2.35 Impact Factor
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    ABSTRACT: Current guidelines recommend cholecystectomy (CCY) during the index admission for mild to moderate biliary pancreatitis as delayed CCY is associated with a substantial risk of recurrent biliary events. Delayed CCY is recommended in severe pancreatitis. The optimal timing of CCY in necrotizing pancreatitis, however, has not been well studied. We sought to determine the safety of single-stage CCY performed at the time of necrosectomy and its effectiveness in preventing subsequent biliary complications.
    Gastroenterology 10/2014; 19(1). DOI:10.1007/s11605-014-2650-x · 13.93 Impact Factor
  • Annals of Emergency Medicine 10/2014; 64(4):S7–S8. DOI:10.1016/j.annemergmed.2014.07.042 · 4.33 Impact Factor
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    ABSTRACT: Introduction Red blood cell (RBC) transfusion is often essential during trauma resuscitation but is associated with high cost and potential adverse outcomes. This study aimed to determine the incidence of potentially avoidable RBC transfusions (PAT) among adult major trauma patients. Materials and Methods A retrospective review of data collected by Registry on patients presenting between Jan 2006 and Dec 2011 was conducted. Eligible patients received at least 1 unit of RBC in the first 24 hours following presentation to the Emergency Department (ED). Episodes of PAT were determined according to haemodynamic stability and post-transfusion haemoglobin levels. Results There were 621 patients included, of whom 224 (36.1%; 95% CI: 32.3-40.0) received PAT. Of them, 132 (58.9%) were haemodynamically stable on arrival and did not require a surgical procedure. Patients with PAT had significantly lower injury severity scores (30 vs 34, p < 0.01), higher presenting systolic blood pressure (129 vs 112 mm Hg, p < 0.01) and a lower frequency of a shock index ≥1 (24.1 vs 65.0%, p < 0.01), compared to those without PAT. They also had a significantly lower mortality (13.4 vs 21.7%, p < 0.01). Conclusions PAT after trauma was common and often delivered to haemodynamically stable patients who did not require surgical procedures. Clinical decision pathways for trauma resuscitation should aim to limit PAT.
    Injury 09/2014; 46(1). DOI:10.1016/j.injury.2014.08.050 · 2.46 Impact Factor
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    ABSTRACT: Intracavitary noncompressible hemorrhage remains a significant cause of preventable death on the battlefield and in the homeland. We previously demonstrated the hemostatic efficacy of an in situ self-expanding poly(urea)urethane foam in a severe, closed-cavity, hepatoportal exsanguination model in swine. We hypothesized that treatment with, and subsequent explantation of, foam would not adversely impact 28-day survival in swine.
    Journal of Trauma and Acute Care Surgery 09/2014; 77(3 Suppl 2):S127-S133. DOI:10.1097/TA.0000000000000380 · 1.97 Impact Factor
  • Journal of the American College of Surgeons 09/2014; 219(3):S97-S98. DOI:10.1016/j.jamcollsurg.2014.07.233 · 4.45 Impact Factor
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    ABSTRACT: With the dramatic growth in the very old population and their concomitant heightened exposure to traumatic injury, the trauma burden among this patient population is estimated to be exponentially increasing.
    08/2014; 149(10). DOI:10.1001/jamasurg.2014.473
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    ABSTRACT: Background Failure to achieve primary fascial closure (PFC) after damage control laparotomy is costly and carries great morbidity. We hypothesized that time from the initial laparotomy to the first take-back operation would be predictive of successful PFC. Methods Trauma patients managed with open abdominal techniques after damage control laparotomy were prospectively followed at 14 Level 1 trauma centers during a 2-year period. Time to the first take-back was evaluated as a predictor of PFC using hierarchical multivariate logistic regression analysis. Results A total of 499 patients underwent damage control laparotomy and were included in this analysis. PFC was achieved in 327 (65.5%) patients. Median time to the first take-back operation was 36 hours (interquartile range 24–48). After we adjusted for patient demographics, resuscitation volumes, and operative characteristics, increasing time to the first take-back was associated with a decreased likelihood of PFC. Specifically, each hour delay in return to the operating room (24 hours after initial laparotomy) was associated with a 1.1% decrease in the odds of PFC (odds ratio 0.989; 95% confidence interval 0.978–0.999; P = .045). In addition, there was a trend towards increased intra-abdominal complications in patients returning after 48 hours (odds ratio 1.80; 95% confidence interval 1.00–3.25; P = .05). Conclusion Data from this prospective, multicenter study demonstrate that delays in returning to the operating room after damage control laparotomy are associated with reductions in PFC. These findings suggest that emphasis should be placed on returning to the operating room within 24 hours after the initial laparotomy if possible (and no later than 48 hours).
    Surgery 08/2014; 156(2). DOI:10.1016/j.surg.2014.04.019 · 3.11 Impact Factor
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    ABSTRACT: OBJECTIVE. The aim of this study is to describe the radiologic imaging findings of primary, secondary, tertiary, and quaternary blast injuries in patients injured in the Boston Marathon bombing on April 15, 2013. MATERIALS AND METHODS. A total of 43 patients presenting to three acute care hospitals and undergoing radiologic investigation within 7 hours of the time of the bombing on April 15, 2013, were included in this study. The radiographic and CT features of these patients were evaluated for imaging findings consistent with primary, secondary, tertiary, and quaternary blast injury. RESULTS. There were no pulmonary or gastrointestinal manifestations of the primary blast wave on imaging. Secondary blast injuries identified on imaging included a total of 189 shrapnel fragments identified in 32 of the 43 patients. The shrapnel was identified most often in the soft tissues of the leg (36.5%), thigh (31.2%), and pelvis (13.2%). Imaging identified 125 ball bearings, 10 nails, one screw, 44 metal fragments, and nine other (gravel, glass, etc.) foreign bodies. CONCLUSION. Injuries from the Boston Marathon bombing were predominantly from the secondary blast wave and resulted in traumatic injuries predominantly of the lower extremities. The most common shrapnel found on radiologic evaluation was the ball bearing.
    American Journal of Roentgenology 08/2014; 203(2):235-239. DOI:10.2214/AJR.14.12549 · 2.74 Impact Factor
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    ABSTRACT: The implementation of the Affordable Care Act stimulated interest in outcomes of patients in Massachusetts, a state mandating health insurance as of 2006. We sought to determine the impact of an insurance mandate on hospital use and outcomes among trauma intensive care unit (ICU) patients.
    Journal of Trauma and Acute Care Surgery 08/2014; 77(2):298-303. DOI:10.1097/TA.0000000000000334 · 1.97 Impact Factor
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    ABSTRACT: We sought to assess the independent effect of concomitant adhesions (CAs) on patient outcome in abdominal surgery.
    Journal of Surgical Research 07/2014; DOI:10.1016/j.jss.2014.07.044 · 2.12 Impact Factor
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    ABSTRACT: BACKGROUND: Noncompressible abdominal bleeding is a significant cause of preventable death oft the battlefield and in the civilian setting, with no effective therapies available at point of injury. We previously reported that a self-expanding polyurethane foam significantly improved survival in a lethal hepatoportal injury model of massive venous hemorrhage. In this study, we hypothesized that foam treatment could improve survival in a lethal iliac, artery injury model in noncoagulopathic swine. METHODS: In swine with a closed abdomen, an iliac artery transection was created, resulting in massive noncompressible exsanguination. After injury, animals were treated with damage-control fluid resuscitation alone (n = 14) or foam treatment in addition to fluids. Two doses of foam treatment were studied: 100 mL (n = 12) and 120 mL (n = 13); all animals were monitored for 3 hours or until death. RESULTS: Foam treatment at both doses resulted in a significant survival benefit and reduction in hemorrhage rate relative to the control group. Median survival time was 135 minutes and 175 minutes for the 120-mL and 100-mL doses, compared with 32 minutes in the control group (p < 0.001 for both groups). Foam resulted in an immediate, persistent improvement in mean arterial pressure and a transient increase in intra-abdominal pressure. The median hemorrhage rate was 0.27 g/kg per minute in the 120-mL group and 0.23 g/kg per minute in the 100-mL group, compared with 1.4 g/kg per minute in the control group (p = 0.003 and 0.006, respectively, as compared with the control). CONCLUSION: Self-expanding foam treatment significantly improves survival in an otherwise lethal, noncompressible, massive, arterial injury. This treatment may provide a prehospital intervention for control of noncompressible abdominal hemorrhage. Copyright (C) 2014 by Lippincott Williams & Wilkins
    Journal of Trauma and Acute Care Surgery 07/2014; 77(1):73-77. DOI:10.1097/TA.0000000000000263 · 1.97 Impact Factor

Publication Stats

9k Citations
1,289.87 Total Impact Points


  • 2006–2015
    • Harvard Medical School
      • Department of Surgery
      Boston, Massachusetts, United States
  • 2008–2014
    • Massachusetts General Hospital
      • • Division of Trauma, Emergency Surgery and Surgical Critical Care
      • • Department of Surgery
      Boston, Massachusetts, United States
  • 2005–2014
    • Harvard University
      Cambridge, Massachusetts, United States
  • 2013
    • University of Michigan
      • Department of Surgery
      Ann Arbor, Michigan, United States
    • Boston University
      Boston, Massachusetts, United States
  • 2012
    • University of Massachusetts Medical School
      • Department of Surgery
      Worcester, Massachusetts, United States
  • 1996–2009
    • University of Southern California
      • Department of Surgery
      Los Angeles, California, United States
  • 2000–2007
    • Keck School of Medicine USC
      Los Ángeles, California, United States
    • California State University, Los Angeles
      Los Ángeles, California, United States
  • 1996–2007
    • University of California, Los Angeles
      • Department of Surgery
      Los Ángeles, California, United States
  • 2004
    • Oregon Health and Science University
      • Department of Surgery
      Portland, OR, United States
  • 2002
    • California State University, Sacramento
      Sacramento, California, United States
  • 1999
    • Santa Barbara Cottage Hospital
      Santa Barbara, California, United States
  • 1994–1998
    • University of the Witwatersrand
      • Department of Surgery
      Johannesburg, Gauteng, South Africa
    • Chris Hani Baragwanath Hospital
      Johannesburg, Gauteng, South Africa
  • 1993
    • University of Johannesburg
      Johannesburg, Gauteng, South Africa