Racial and Ethnic Disparities in Operative Experience Among General Surgery Residents: A Multi-Institutional Study from the US ROPE Consortium.

OBJECTIVE: To determine the relationship between race/ethnicity and case volume among graduating surgical residents. BACKGROUND: Racial/ethnic minority individuals face barriers to entry and advancement in surgery; however, no large-scale investigations of the operative experience of racial/ethnic minority residents have been performed. METHODS: A multi-institutional retrospective analysis of the Accreditation Council for Graduate Medical Education case logs of categorical general surgery residents at 20 programs in the US Resident OPerative Experience Consortium database was performed. All residents graduating between 2010 and 2020 were included. The total, surgeon chief, surgeon junior, and teaching assistant case volumes were compared between racial/ethnic groups. RESULTS: The cohort included 1343 residents. There were 211 (15.7%) Asian, 65 (4.8%) Black, 73 (5.4%) Hispanic, 71 (5.3%) "Other" (Native American or Multiple Race), and 923 (68.7%) White residents. On adjusted analysis, Black residents performed 76 fewer total cases (95% CI, -109 to -43, P <0.001) and 69 fewer surgeon junior cases (-98 to -40, P <0.001) than White residents. Comparing adjusted total case volume by graduation year, both Black residents and White residents performed more cases over time; however, there was no difference in the rates of annual increase (10 versus 12 cases per year increase, respectively, P =0.769). Thus, differences in total case volume persisted over the study period. CONCLUSIONS: In this multi-institutional study, Black residents graduated with lower case volume than non-minority residents throughout the previous decade. Reduced operative learning opportunities may negatively impact professional advancement. Systemic interventions are needed to promote equitable operative experience and positive culture change.

Defining the operative time threshold for safety in patients undergoing robotic pancreaticoduodenectomy.

BACKGROUND: Robotic pancreaticoduodenectomy (RPD) is a safe and efficacious procedure in appropriately selected patients, though frequently with increased operative times compared to open pancreaticoduodenectomy (OPD). METHODS: From 2014 to 2019, patients who underwent elective, low-risk, RPDs and OPDs in the NSQIP database were isolated. The operative time threshold (OTT) for safety in RPD patients was estimated by identifying the operative time at which complication rates for RPD patients exceeded the complication rate of the benchmark OPD control. RESULTS: Of 6270 patients identified, 939 (15%) underwent RPD and 5331 (85%) underwent OPD. The incidence of major morbidity or mortality for the OPD cohort was 35.1%. The OTT was identified as 7.7 h. Patients whose RPDs were above the OTT experienced a higher incidence of major morbidity (42.5% vs. 35.0%, p < 0.01) and 30-day mortality (2.7% vs. 1.2%, p = 0.03) than the OPD cohort. Preoperative obstructive jaundice (OR: 1.47, [95% CI: 1.08-2.01]) and pancreatic duct size <3 mm (OR: 2.44, [95% CI: 1.47-4.06]) and 3-6 mm (OR: 2.15, [95% CI: 1.31-3.52]) were risk factors for prolonged RPDs on multivariable regression. CONCLUSION: The operative time threshold for safety, identified at 7.7 h, should be used to improve patient selection for RPDs and as a competency-based quality benchmark.

Safety and use of late-turndown liver allografts to increase rate of transplantation.

BACKGROUND: The demand for liver transplants (LT) in the United States far surpasses the availability of allografts. New allocation schemes have resulted in occasional difficulties with allograft placement and increased intraoperative turndowns. We aimed to evaluate the outcomes related to use of late-turndown liver allografts. METHODS: A review of prospectively collected data of LTs at a single center from July 2019 to July 2023 was performed. Late-turndown placement was defined as an open offer 6 h prior to donation, intraoperative turndown by primary center, or post-cross-clamp turndown. RESULTS: Of 565 LTs, 25.1% (n = 142) received a late-turndown liver allograft. There were no significant differences in recipient age, gender, BMI, or race (all p > 0.05), but MELD was lower for the late-turndown LT recipient group (median 15 vs 21, p < 0.001). No difference in 30-day, 6-month, or 1-year survival was noted on logistic regression, and no difference in patient or graft survival was noted on Cox proportional hazard regression. Late-turndown utilization increased during the study from 17.2% to 25.8%, and median waitlist time decreased from 77 days in 2019 to 18 days in 2023 (p < 0.001). CONCLUSION: Use of late-turndown livers has increased and can increase transplant rates without compromising post-transplant outcomes with appropriate selection.

Are General Surgery Residencies Preparing Graduates for the Practice of Today's General Surgeon? An Analysis of American Board of Surgery Data From Applicants and Re-certifying Surgeons.

OBJECTIVE: To compare the operative experience of general surgery residents and practicing general surgeons. SUMMARY OF BACKGROUND DATA: The scope of general surgery has evolved, yet it remains unknown whether residents are being exposed to the right mix of operations during residency. METHODS: A retrospective review of operative case logs submitted to the American Board of Surgery by US general surgery graduates and practicing general surgeons from 2013 to 2017 was performed. The operative experience of both cohorts was calculated as a proportion of total experience and ranked by frequency. The proportional experience between cohorts was analyzed using factorial analysis of variance. RESULTS: During the 5-year period, 5482 graduates applied for initial American Board of Surgery certification, and 4152 diplomates applied for recertification. Among all operative domains, the graduate experience was similar to that of diplomates in 6 of 12 areas (abdomen, alimentary tract, endoscopy, endocrine, other, skin/soft tissue; all P > 0.05). Residents have a greater experience in subspecialty areas (pediatric, thoracic, trauma, vascular, and plastic) at the expense of fewer breast procedures (all P < 0.05). The 30 operations most commonly performed by graduates comprised 67% of their total operative experience. Among these, residents performed 25 cases ≥10 times, 14 cases ≥20 times, and 7 cases ≥40 times. CONCLUSIONS: The operative experience of graduating US general surgery residents is largely similar to that of practicing general surgeons, particularly for core general surgery domains. These data offer reassurance that surgical training in the modern era appropriately exposes residents to the operations they may perform in practice.

10 Year Analysis of Pediatric Surgery Fellowship Match and Operative Experience: Concerning Trends?

OBJECTIVE: This paper aims to evaluate the pediatric surgery training pipeline vis-à-vis the pediatric surgery match and operative experience of pediatric surgery fellows. SUMMARY OF BACKGROUND DATA: Pediatric surgery remains a competitive surgical subspecialty. However, there is concern that operative experience for pediatric surgery fellows is changing. This paper examines the selectivity of the pediatric surgery match, along with the operative experience of pediatric surgery fellows to characterize the state of pediatric surgery training. METHODS: The pediatric surgery fellowship match was analyzed from the National Resident Matching Program data from 2010 to 2019. Selectivity among fellowships was compared using analysis of variance with Dunnett test. Operative log data for pediatric fellows was analyzed using the Accreditation Council for Graduate Medical Education case logs from 2009 to 2019. Linear regression analysis was used to evaluate trends in operative volume over time. RESULTS: Pediatric surgery had the highest proportion of unmatched applicants (47.2% ± 5.3%) and lowest proportion of unfilled positions (1.4% ± 1.6%) when compared to other National Resident Matching Program surgical fellowships. Accreditation Council for Graduate Medical Education case log analysis revealed a statistically significant decrease in cases for graduating fellows (-5.3 cases/year, P < 0.05). Total index cases decreased (-4.7 cases/year, P < 0.01, R 2 = 0.83) such that graduates in 2019 completed 59 fewer index operations than graduates in 2009. CONCLUSION: Although pediatric surgery fellowship remains highly selective there has been a decline in the operative experience for graduating fellows. This highlights the need for evaluation of training paradigms and operative exposure in pediatric surgery to ensure the training of competent pediatric surgeons.

Disparities in the Operative Experience Between Female and Male General Surgery Residents: A Multi-institutional Study From the US ROPE Consortium.

OBJECTIVE: To examine differences in resident operative experience between male and female general surgery residents. BACKGROUND: Despite increasing female representation in surgery, sex and gender disparities in residency experience continue to exist. The operative volume of male and female general surgery residents has not been compared on a multi-institutional level. METHODS: Demographic characteristics and case logs were obtained for categorical general surgery graduates between 2010 and 2020 from the US Resident OPerative Experience Consortium database. Univariable, multivariable, and linear regression analyses were performed to compare differences in operative experience between male and female residents. RESULTS: There were 1343 graduates from 20 Accreditation Council for Graduate Medical Education-accredited programs, and 476 (35%) were females. There were no differences in age, race/ethnicity, or proportion pursuing fellowship between groups. Female graduates were less likely to be high-volume residents (27% vs 36%, P < 0.01). On univariable analysis, female graduates performed fewer total cases than male graduates (1140 vs 1177, P < 0.01), largely due to a diminished surgeon junior experience (829 vs 863, P < 0.01). On adjusted multivariable analysis, female sex was negatively associated with being a high-volume resident (OR = 0.74, 95% CI: 0.56 to 0.98, P = 0.03). Over the 11-year study period, the annual total number of cases increased significantly for both groups, but female graduates (+16 cases/year) outpaced male graduates (+13 cases/year, P = 0.02). CONCLUSIONS: Female general surgery graduates performed significantly fewer cases than male graduates. Reassuringly, this gap in operative experience may be narrowing. Further interventions are warranted to promote equitable training opportunities that support and engage female residents.

General Surgery Residency Virtual Recruitment During the Pandemic: An Analysis of Applicant Surveys.

INTRODUCTION: The COVID-19 pandemic forced a sudden change from in-person to virtual interviews for the general surgery residency match. General surgery programs and applicants adopted multiple strategies to best mimic in-person recruitment. The purpose of this study was to evaluate applicant opinions of the virtual recruitment format. MATERIALS AND METHODS: Postinterview survey responses for applicants interviewing at a single general surgery residency program in the 2020-2021 and 2021-2022 cycles were evaluated. All interviewed applicants were sent an anonymous survey assessing the virtual interview structure, their impression of the program, and their opinions on recruitment in the future. RESULTS: The response rate was 31.2% (n = 60). Most (88.4%) respondents reported a more favorable view of the program after a virtual interview. Factors that were most likely to create a favorable impression were residents (89.6%) and culture (81.0%). 50.8% of applicants favored virtual-only interviews. The majority of applicants (60.3%), however, preferred the virtual interview remain a component of the application process, 34.4% recommended that virtual interviews be used as an initial screen before in-person invites, while 19.0% suggested applicants should interview in-person or virtually without penalty. 62.1% favored capping the number of interviews offered by programs and accepted by applicants. CONCLUSIONS: The virtual interview format for general surgery residency allows applicants to effectively evaluate a residency program. Applicants are in favor of a combination of virtual and in-person interviews in the future. Innovation in the recruitment process, including limiting the number of applications and incorporating virtual events, is supported by applicants.

Examining the transplant case composition of early-career transplant surgeons.

Fellowship training established by the American Society of Transplant Surgeons and certified by the Transplant Accreditation and Certification Council provides trainees with broad exposure and practice readiness for the core aspects of abdominal transplantation. However, the operative case mix of a new transplant surgeon early in practice is unknown. This study examined the volume and composition of the transplant case mix of early-career transplant surgeons to better inform residents interested in transplantation about potential career opportunities following fellowship. cas 209 early-career transplant surgeons were identified from the UNOS database containing encrypted surgeon-specific identifiers and were included in this study. At 5 years into practice, there were 85 (40.7%) kidney-predominant, 38 (18.2%) liver-predominant, and 86 (41.1%) multiorgan transplant surgeons. Comparing surgeon subgroups, multiorgan surgeons performed more transplants in year 5 of practice than both liver-predominant and kidney-predominant surgeons (both p < .05). This is the first study to describe the transplant case composition of the early-career transplant surgeons. This data can be used to inform aspiring transplant surgeons about potential career opportunities and to assist fellowship programs in guiding and mentoring fellows.

The Kidney Transplant Equity Index: Improving Racial and Ethnic Minority Access to Transplantation.

OBJECTIVES: To develop a scalable metric which quantifies kidney transplant (KT) centers' performance providing equitable access to KT for minority patients, based on the individualized prelisting prevalence of end-stage renal disease (ESRD). BACKGROUND: Racial and ethnic disparities for access to transplant in patients with ESRD are well described; however, variation in care among KT centers remains unknown. Furthermore, no mechanism exists that quantifies how well a KT center provides equitable access to KT for minority patients with ESRD. METHODS: From 2013 to 2018, custom datasets from the United States Renal Data System and United Network for Organ Sharing were merged to calculate the Kidney Transplant Equity Index (KTEI), defined as the number of minority patients transplanted at a center relative to the prevalence of minority patients with ESRD in each center's health service area. Markers of socioeconomic status and recipient outcomes were compared between high and low KTEI centers. RESULTS: A total of 249 transplant centers performed 111,959 KTs relative to 475,914 nontransplanted patients with ESRD. High KTEI centers performed more KTs for Black (105.5 vs 24, P <0.001), Hispanic (55.5 vs 7, P <0.001), and American Indian (1.0 vs 0.0, P <0.001) patients than low KTEI centers. In addition, high KTEI centers transplanted more patients with higher unemployment (52 vs 44, P <0.001), worse social deprivation (53 vs 46, P <0.001), and lower educational attainment (52 vs 43, P <0.001). While providing increased access to transplant for minority and low socioeconomic status populations, high KTEI centers had improved patient survival (hazard ratio: 0.86, 95% confidence interval: 0.77-0.95). CONCLUSIONS: The KTEI is the first metric to quantify minority access to KT incorporating the prelisting ESRD prevalence individualized to transplant centers. KTEIs uncover significant national variation in transplant practices and identify highly equitable centers. This novel metric should be used to disseminate best practices for minority and low socioeconomic patients with ESRD.

The volume-outcomes relationship in donation after circulatory death liver transplantation.

BACKGROUND: Donation after circulatory death (DCD) liver transplantation (LT) has become an effective mechanism for expanding the donor pool and decreasing waitlist mortality. However, it is unclear if low-volume DCD centers can achieve comparable outcomes to high-volume centers. METHODS: From 2011 to 2019 utilizing the United Network for Organ Sharing (UNOS) database, liver transplant centers were categorized into tertiles based on their annual volume of DCD LTs. Donor selection, recipient selection, and survival outcomes were compared between very-low volume (VLV, n = 1-2 DCD LTs per year), low-volume (LV, n = 3-5), and high-volume (HV, n > 5) centers. RESULTS: One hundred and ten centers performed 3273 DCD LTs. VLV-centers performed 339 (10.4%), LV-centers performed 627 (19.2%), and HV-centers performed 2307 (70.4%) LTs. 30-day, 90-day, and 1-year patient and graft survival were significantly increased at HV-centers (all P < .05). Recipients at HV-centers had shorter waitlist durations (P < .01) and shorter hospital lengths of stay (P < .01). On multivariable regression, undergoing DCD LT at a VLV-center or LV-center was associated with increased 1-year patient mortality (VLV-OR:1.73, 1.12-2.69) (LV-OR: 1.42, 1.01-2.00) and 1-year graft failure (VLV-OR: 1.79, 1.24-2.58) (LV-OR: 1.28, .95-1.72). DISCUSSION: Increased annual DCD liver transplant volume is associated with improved patient and graft survival.

Extinguishing burnout: National analysis of predictors and effects of burnout in abdominal transplant surgery fellows.

Burnout among surgeons has been attributed to increased workload and decreased autonomy. Although prior studies have examined burnout among transplant surgeons, no studies have evaluated burnout in abdominal transplant surgery fellows. The objective of our study was to identify predictors of burnout and understand its impact on personal and patient care during fellowship. A survey was sent to all abdominal transplant surgery fellows in an American Society of Transplant Surgeons-accredited fellowship. The response rate was 59.2% (n = 77) and 22.7% (n = 17) of fellows met criteria for burnout. Fellows with lower grit scores were more likely to exhibit burnout compared with fellows with higher scores (3.6 vs 4.0, P = .026). Those with burnout were more likely to work >100 hours per week (58.8% vs 27.6%, P = .023), have severe work-related stress (58.8% vs 22.4%, P = .010), consider quitting fellowship (94.1% vs 20.7%, P < .001), or make a medical error (35.3% vs 5.2%, P = .003). This national analysis of abdominal transplant fellows found that burnout rates are relatively low, but few fellows engage in self-care. Personal and program-related factors attribute to burnout and it has unacceptable effects on patient care. Transplant societies and fellowship programs should develop interventions to give fellows tools to prevent and combat burnout.

Expanding the Donor Pool: First Use of Hepatitis B Virus Nat Positive Solid Organ Allografts Into Seronegative Recipients.

OBJECTIVES: The aim of this study was to assess the 1-year safety and effectiveness of HBV Nucleic Acid Test positive (HBV NAT+) allografts in seronegative kidney transplant (KT) and liver transplant (LT) recipients. SUMMARY BACKGROUND DATA: Despite an ongoing organ shortage, the utilization of HBV NAT+ allografts into seronegative recipients has not been investigated. METHODS: From January 2017 to October 2020, a prospective cohort study was conducted among consecutive KT and LT recipients at a single institution. Primary endpoints were post-transplant HBV viremia, graft and patient survival. RESULTS: With median follow-up of 1-year, there were no HBV-related complications in the 89 HBV NAT+ recipients. Only 9 of 56 KTs (16.1%) and 9 of 33 LTs (27.3%) experienced post-transplant HBV viremia at a median of 185 (KT) and 269 (LT) days postoperatively. Overall, viremic episodes resolved to undetected HBV DNA after a median of 80 days of entecavir therapy in 16 of 18 recipients. Presently, 100% of KT recipients and 93.9% of LT recipients are HBV NAT- with median follow-up of 13 months, whereas 0 KT and 8 LT (24.2%) recipients are HBV surface antigen positive indicating chronic infection. KT and LT patient and allograft survival were not different between HBV NAT+ and HBV NAT- recipients (P > 0.05), whereas HBV NAT+ KT recipients had decreased waitlist time and pretransplant duration on dialysis (P < 0.01). CONCLUSIONS: This is the largest series describing the transplantation of HBV NAT+ kidney and liver allografts into HBV seronegative recipients without chronic HBV viremia or decreased 1-year patient and graft survival. Increasing the utilization of HBV NAT+ organs in nonviremic recipients can play a role in decreasing the national organ shortage.

Long-term outcomes in patients with obesity and renal disease after sleeve gastrectomy.

Morbid obesity is a barrier to kidney transplant in patients with end-stage renal disease (ESRD). Laparoscopic sleeve gastrectomy (SG) is an increasingly considered intervention, but the safety and long-term outcomes are uncertain. We reviewed prospectively collected data on patients with ESRD and chronic kidney disease (CKD) undergoing SG from 2011 to 2018. There were 198 patients with ESRD and 45 patients with CKD (stages 1-4) who met National Institutes of Health guidelines for bariatric surgery and underwent SG; 72% and 48% achieved a body mass index of ≤ 40 and ≤ 35 kg/m2 , respectively. The mean percentages of total weight loss and excess weight loss were 18.9 ± 10.8% and 38.2 ± 20.3%, respectively. SG reduced hypertension (85.8% vs 52.1%), decreased antihypertensive medication use (1.6 vs 1.0) (P < .01 each), and reduced incidence of diabetes (59.6% vs 32.5%, P < .01). Of the 71 patients with ESRD who achieved a body mass index of ≤ 40 kg/m2 , 45 were waitlisted and received a kidney transplant, whereas 10 remain on the waitlist. Mortality rate after SG was 1.8 per 100 patient-years, compared with 7.3 for non-SG. Patients with stage 3a or 3b CKD exhibited improved glomerular filtration rate (43.5 vs 58.4 mL/min, P = .01). In conclusion, SG safely improves transplant candidacy while providing significant, sustainable effects on weight loss, reducing medical comorbidities, and possibly improving renal function in stage 3 patients.

Outcomes of en bloc simultaneous liver-kidney transplantation compared to the traditional technique.

Simultaneous liver-kidney transplantation (SLKT) is indicated for patients with end-stage liver disease (ESLD) and concurrent renal insufficiency. En bloc SLKT is an alternative to traditional separate implantations, but studies comparing the two techniques are limited. The en bloc technique maintains renal outflow via donor infrahepatic vena cava and inflow via anastomosis of donor renal artery to donor splenic artery. Comparison of recipients of en bloc (n = 17) vs traditional (n = 17) SLKT between 2013 and 2017 was performed. Recipient demographics and comorbidities were similar. More recipients of traditional SLKT were dialysis dependent (82.4% vs 41.2%, P = .01) with lower baseline pretransplant eGFR (14 vs 18, P = .01). En bloc SLKT was associated with shorter kidney cold ischemia time (341 vs 533 minutes, P < .01) and operative time (374 vs 511 minutes, P < .01). Two en bloc patients underwent reoperation for kidney allograft inflow issues due to kinking and renal steal. Early kidney allograft dysfunction (23.5% in both groups), 1-year kidney graft survival (88.2% vs 82.4%, P = 1.0), and posttransplantation eGFR were similar between groups. In our experience, the en bloc SLKT technique is safe and feasible, with comparable outcomes to the traditional method.

Use of Hepatitis C Nucleic Acid Test-Positive Liver Allografts in Hepatitis C Virus Seronegative Recipients.

Because of underutilization of liver allografts, our center previously showed that hepatitis C virus (HCV) antibody-positive/nucleic acid test (NAT)-negative livers when transplanted into HCV nonviremic recipients were safe with a 10% risk of HCV transmission. Herein, we present our single-center prospective experience of using HCV NAT+ liver allografts transplanted into HCV NAT- recipients. An institutional review board-approved matched cohort study was conducted examining post- liver transplantation (LT) outcomes of HCV- patients who received HCV NAT+ organs (treatment group) compared with matched recipients with HCV NAT- organs (matched comparator group) between June 2018 to October 2019. The primary endpoint was success of HCV treatment and elimination of HCV infection. The secondary outcomes included the 30-day and 1-year graft and patient survival as well as perioperative complications. There were 32 recipients enrolled into each group. Because of 1 death in the index admission, 30/31 patients (97%) were given HCV treatment at a median starting time of 47 days (18-140 days) after LT. A total of 19 (63%) patients achieved sustained virological response at week 12 (SVR12). Another 6 patients achieved end-of-treatment response, while 5 remained on therapy and 1 is yet to start treatment. No HCV treatment failure has been noted. There were no differences in 30-day and 1-year graft and patient survival, length of hospital stay, biliary or vascular complications, or cytomegalovirus viremia between the 2 groups. In this interim analysis of a matched cohort study, which is the first and largest study to date, the patients who received the HCV NAT+ organs had similar outcomes regarding graft function, patient survival, and post-LT complications.

Roux-en-Y enterolith leading to obstruction and ischemic necrosis after pediatric orthotopic liver transplantation.

Biliary complications are a common cause of morbidity after liver transplantation, with biliary stone formation being a known occurrence generally upstream of a stricture. A 12-year-old boy, who underwent an orthotopic liver transplantation at 11 months of age for biliary atresia, presented acutely with fever and abdominal pain. Cross-sectional imaging revealed Roux-en-Y limb dilatation and thickening. He was explored and was found to have an ischemic Roux limb secondary to an obstructing enterolith. A segmental bowel resection and revision of his hepaticojejunostomy was performed. While rare, biliary enteroliths may present as either a bowel obstruction or cholangitis and should be considered in the differential diagnosis of a patient following biliary reconstruction. Additionally, anatomic etiologies should be considered and potentially surgically corrected.

Expanding the Margins: High Volume Utilization of Marginal Liver Grafts Among >2000 Liver Transplants at a Single Institution.

OBJECTIVE: Marginal livers (ML) have been used to expand the donor pool. National utilization of MLs is variable, and in some centers, they are never used. We examined the outcomes of MLs in the largest single center series of MLs used to date and compared outcomes to standard (SL) and living donor (LD) livers. METHODS: Analysis of a prospectively maintained database of all liver transplants performed at our institution from 1998 to 2016. ML grafts were defined as livers from donors >70, livers discarded regionally and shared nationally, livers with cold ischemic time >12 hours, livers from hepatitis C virus positive donors, livers from donation after cardiac death donors, livers with >30% steatosis, and livers split between 2 recipients. RESULTS: A total of 2050 liver transplant recipients were studied, of these 960 (46.8%) received ML grafts. ML recipients were more likely to have lower MELDs and have hepatocellular carcinoma. Most MLs used were from organs turned down regionally and shared nationally (69%) or donors >70 (22%). Survival of patients receiving MLs did not significantly differ from patients receiving SL grafts (P = 0.08). ML and SL recipients had worse survival than LDs (P < 0.01). Despite nearly half of our recipients receiving MLs, overall survival was significantly better than national survival over the same time period (P = 0.04). Waitlist mortality was significantly lower in our series compared with national results (19% vs 24.0%, P < 0.0001). CONCLUSIONS: Outcomes of recipients of ML grafts are comparable to SL transplants. Despite liberal use of these grafts, we have been able to successfully reduce waitlist mortality while exceeding national post-transplant survival metrics.

Surgical resident learning styles have changed with work hours.

BACKGROUND: The Accreditation Council for Graduate Medical Education instituted the 80-h workweek for residency programs in 2003. This presented a unique challenge for surgery residents who must acquire a medical and technical knowledge base during training. Therefore, learning should be delivered in an environment congruent with an individual's learning style. In this study, we evaluated the learning styles of general surgery residents to determine how learning styles changed after the implementation to the 80-h workweek. MATERIALS AND METHODS: Kolb learning style inventory was taken by general surgery residents at the University of Cincinnati's Department of Surgery, and results from 1999-2012 were analyzed. Statistical analysis was performed using the chi-squared, logistic regression and Wilcoxon rank-sum test. Significance was defined as a P value of <0.05. RESULTS: A total of 411 responses were obtained from 115 residents. Surgical residents were primarily converging (59.0%) and assimilating (19.1%) learners before 2003. However, there was a shift in predominate learning styles after the institution of the 80-h workweek to converging (43.9%) and accommodating (40.4%, P < 0.001). Surgical residents were also more likely to be team-based learners after the start of the 80-h workweek (odds ratio = 2.13, P = 0.0016). CONCLUSIONS: After the institution of the 80-h workweek, most general surgery residents remained action-based learners. However, there was a shift within this majority toward a preference for team-based learning. This change paralleled the transition to a more team-based approach to patient care with the implementation of the 80-h workweek. These findings are important for surgical educators to consider in the development of surgical resident curriculum.

CXC chemokine receptor-4 signaling limits hepatocyte proliferation after hepatic ischemia-reperfusion in mice.

The role of stromal cell-derived factor-1 (SDF-1 or CXCL12) and its receptor CXC chemokine receptor-4 (CXCR4) in ischemic liver injury and recovery has not been studied. Some reports suggest that this chemokine may aid in liver regeneration, but others suggest that it may be profibrotic through its activation of hepatic stellate cells. In this study we sought to elucidate the role of SDF-1 and its receptor CXCR4 during liver injury, recovery, and regeneration after ischemia-reperfusion (I/R). A murine model of partial (70%) I/R was used to induce liver injury and study the reparative and regenerative response. CXCR4 was expressed constitutively in the liver, and hepatic levels of SDF-1 peaked 8 h after reperfusion but remained significantly increased for 96 h. Treatment of mice with the CXCR4 antagonist AMD3100 or agonist SDF-1 had no effect on acute liver injury assessed 8 h after I/R. However, treatment with AMD3100 increased hepatocyte proliferation after 72 and 96 h of reperfusion and reduced the amount of liver necrosis. In contrast, treatment with SDF-1 significantly decreased hepatocyte proliferation. These effects appeared to be dependent on the presence of liver injury, as AMD3100 and SDF-1 had no effect on hepatocyte proliferation or liver mass in mice undergoing 70% partial hepatectomy. The data suggest that signaling through CXCR4 is detrimental to liver recovery and regeneration after I/R and that clinical therapy with a CXCR4 antagonist may improve hepatic recovery following acute liver injury.

Inhibition of acidic sphingomyelinase reduces established hepatic fibrosis in mice.

AIM: Liver fibrosis occurs as a result of several chronic liver diseases and leads to portal hypertension, cirrhosis and liver failure, often requiring liver transplantation. Activated hepatic stellate cells (HSC) are known to contribute to liver fibrosis, but currently there are no effective therapies for the treatment of established liver fibrosis. Activation of the acidic sphingomyelinase (ASM) has been shown to be involved in HSC activation. In the present study we investigated whether treatment with the ASM inhibitor, amitriptyline (TCA), could prevent and/or reverse fibrosis induced in mice by carbon tetrachloride (CCl4 ). METHODS: Mice were treated with CCl4 for 8 weeks to induce fibrosis. Concurrently, mice received drinking water with or without 180 mg/L TCA. RESULTS: Mice receiving TCA in the water had decreased hepatic collagen deposition and reduced liver mRNA expression of the fibrogenic mediators, transforming growth factor (TGF)-ß1, tissue inhibitor of matrix metalloproteinase-1, collagen and tumor necrosis factor-α. TCA treatment also reduced HSC activation determined by α-smooth muscle actin staining. In a separate set of experiments, mice were treated with CCl4 for 5 weeks prior to treatment with TCA, to test whether TCA had any effect on established fibrosis. Remarkably, in mice with established fibrosis, treatment with TCA significantly reduced collagen deposition, HSC activation, and prevented portal hypertension and improved hepatic architecture. Treatment of isolated HSC in vitro with TCA completely inhibited TGF-ß1-induced collagen expression and platelet-derived growth factor-ß-ß-induced proliferation. CONCLUSION: The data suggest that ASM is a critical signaling component in HSC for the development of liver fibrosis and represents an important therapeutic target.