Vikrom K. Dhar

Does radiologic response correlate to pathologic response in patients undergoing neoadjuvant therapy for borderline resectable pancreatic malignancy

In patients with borderline resectable pancreas cancers, clinicians frequently consider radiographic response as the primary driver of whether patients should be offered surgical intervention following neoadjuvant therapy (NT). We sought to determine any correlation between radiographic and pathologic response rates following NT.

What matters after sleeve gastrectomy: patient characteristics or surgical technique?

Background. The impact of operative technique on outcomes in laparoscopic sleeve gastrectomy has been explored previously; however, the relative importance of patient characteristics remains unknown. Our aim was to characterize national variability in operative technique for laparoscopic sleeve gastrectomy and determine whether patient‐specific factors are more critical to predicting outcomes. Methods. We queried the database of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program for laparoscopic sleeve gastrostomies performed in 2015 (n = 88,845). Logistic regression models were used to determine predictors of postoperative outcomes. Results. In 2015, >460 variations of laparoscopic sleeve gastrectomy were performed based on combinations of bougie size, distance from the pylorus, use of staple line reinforcement, and oversewing of the staple line. Despite such substantial variability, technique variants were not predictive of outcomes, including perioperative morbidity, leak, or bleeding (all P ≥ .05). Instead, preoperative patient characteristics were found to be more predictive of these outcomes after laparoscopic sleeve gastrectomy. Only history of gastroesophageal disease (odds ratio 1.44, 95% confidence interval 1.08–1.91, P < .01) was associated with leak. Conclusion. Considerable variability exists in technique among surgeons nationally, but patient characteristics are more predictive of adverse outcomes after laparoscopic sleeve gastrectomy. Bundled payments and reimbursement policies should account for patient‐specific factors in addition to current accreditation and volume thresholds when deciding risk‐adjustment strategies.

Not all operative experiences are created equal: a 19-year analysis of a single center's case logs

BACKGROUND Although national operative volumes have remained stable, surgical educators should appreciate the changing experience of todays surgical residents. We set out to evaluate operative volume trends at our institution and study the impact of resident learning styles on operative experience. MATERIALS AND METHODS The Accreditation Council for Graduate Medical Education operative log data from 1999 to 2017 for a single general surgery residency program were examined. All residents completed the Kolb Learning Style Inventory. Statistical analyses were performed using linear regression analysis, Students t-test, and Fischers exact test. RESULTS Over the study period, 106 general surgery residents graduated from our program. There were 87% action learners and 13% observation learners. Although there was no change in total major, total chief, or total non-chief cases, a decrease in teaching assistant cases was observed. Subcategory analysis revealed that there was an increase in operative volume on graduation in the following categories: skin, soft tissue, and breast; alimentary tract; abdomen; pancreas; operative trauma; pediatric; basic laparoscopy; complex laparoscopy; and endoscopy with a concurrent decrease in liver, vascular, and endocrine. Learning style analysis found that action learners completed significantly more cases than observation learners in most domains in which operative volume increased. CONCLUSIONS While the operative volume at our center remained stable over the study period, the experience of general surgery residents has become narrowed toward a less subspecialized, general surgery experience. These shifts may disproportionally impact trainees as observation learners operate less than action learners. Residency programs should therefore incorporate methods such as learning style assessment to identify residents at risk of a suboptimal experience.

Laparoscopic sleeve gastrectomy improves renal transplant candidacy and posttransplant outcomes in morbidly obese patients

Morbid obesity is a barrier to kidney transplantation due to inferior outcomes, including higher rates of new‐onset diabetes after transplantation (NODAT), delayed graft function (DGF), and graft failure. Laparoscopic sleeve gastrectomy (LSG) increases transplant eligibility by reducing BMI in kidney transplant candidates, but the effect of surgical weight loss on posttransplantation outcomes is unknown. Reviewing single‐center medical records, we identified all patients who underwent LSG before kidney transplantation from 2011‐2016 (n = 20). Post‐LSG kidney recipients were compared with similar‐BMI recipients who did not undergo LSG, using 2:1 direct matching for patient factors. McNemars test and signed‐rank test were used to compare groups. Among post‐LSG patients, mean BMI ± standard deviation (SD) was 41.5 ± 4.4 kg/m2 at initial encounter, which decreased to 32.3 ± 2.9 kg/m2 prior to transplantation (P < .01). No complications, readmissions, or mortality occurred following LSG. After transplantation, one patient (5%) experienced DGF, and no patients experienced NODAT. Allograft and patient survival at 1‐year posttransplantation was 100%. Compared with non‐LSG patients, post‐LSG recipients had lower rates of DGF (5% vs 20%) and renal dysfunction–related readmissions (10% vs 27.5%) (P < .05 each). Perioperative complications, allograft survival, and patient survival were similar between groups. These data suggest that morbidly obese patients with end‐stage renal disease who undergo LSG to improve transplant candidacy, achieve excellent posttransplantation outcomes.

Downstaging therapy followed by liver transplantation for hepatocellular carcinoma beyond Milan criteria

Background. Orthotopic liver transplantation is a curative treatment for hepatocellular carcinoma within Milan criteria, but these criteria preclude many patients from transplant candidacy. Recent studies have demonstrated that downstaging therapy can reduce tumor burden to meet conventional criteria. The present study reports a single‐center experience with tumor downstaging and its effects on post–orthotopic liver transplantation outcomes. Methods. All patients with hepatocellular carcinoma who were evaluated by our multidisciplinary liver services team from 2012 to 2016 were identified (N = 214). Orthotopic liver transplantation candidates presenting outside of Milan criteria at initial radiographic diagnosis and/or an initial alpha‐fetoprotein >400 ng/mL were categorized as at high risk for tumor recurrence and post‐transplant mortality. Results. Of the 214 patients newly diagnosed with hepatocellular carcinoma, 73 (34.1%) eventually underwent orthotopic liver transplantation. The majority of patients who did not undergo orthotopic liver transplantation were deceased or lost to follow‐up (47.5%), with 14 of 141 (9.9%) currently listed for transplantation. Among transplanted patients, 21 of 73 (28.8%) were considered high‐risk candidates. All 21 patients were downstaged to within Milan criteria with an alpha‐fetoprotein <400 ng/mL before orthotopic liver transplantation, through locoregional therapies. Recurrence of hepatocellular carcinoma was higher but acceptable between downstaged high‐risk and traditional candidates (9.5% vs 1.9%; P > .05) at a median follow‐up period of 17 months. Downstaged high‐risk candidates had a similar overall survival compared with those transplanted within Milan criteria (log‐rank P > .05). Conclusions. In highly selected cases, patients with hepatocellular carcinoma outside of traditional criteria for orthotopic liver transplantation may undergo downstaging therapy in a multidisciplinary fashion with excellent post‐transplant outcomes. These data support an aggressive downstaging approach for selected patients who would otherwise be deemed ineligible for transplantation.

Addressing the challenges of sleeve gastrectomy in end-stage renal disease: Analysis of 100 consecutive renal failure patients

Background. While previous studies have demonstrated short‐term efficacy of laparoscopic sleeve gastrectomy in candidates awaiting renal transplantation, the combination of morbid obesity and end‐stage renal disease presents unique challenges to perioperative care. We demonstrate how increasing experience and the development of postoperative care guidelines can improve outcomes in this high‐risk population. Methods. Single‐center medical records were reviewed for renal transplantation candidates undergoing laparoscopic sleeve gastrectomy between 2011 and 2015 by a single surgeon. Postoperative care protocols were established and continually refined throughout the study period, including a multidisciplinary approach to inpatient management and hospital discharge planning. The first 100 laparoscopic sleeve gastrectomy patients were included and divided into 4 equal cohorts based on case sequence. Results. Compared with the first 25 patients undergoing laparoscopic sleeve gastrectomy, the last 25 patients had shorter operative times (97.8 ± 27.9 min vs 124.2 ± 33.6 min), lower estimated blood loss (6.6 ± 20.8 mL vs 34.0 ± 38.1 mL), and shorter hospital duration of stay (1.7 ± 2.1 days vs 2.9 ± 0.7 days) (P < .01 each). Readmission rates, complications, and 1‐year mortality did not differ significantly. Conclusion. Increasing experience and the development of clinical care guidelines in this high‐risk population is associated with reduced health care resource utilization and improved perioperative outcomes.

Combination oral and mechanical bowel preparations decreases complications in both right and left colectomy

Background. Before elective colectomy, many advocate mechanical bowel preparation with oral antibiotics, whereas enhanced recovery pathways avoid mechanical bowel preparations. The optimal preparation for right versus left colectomy is also unclear. We sought to determine which strategy for bowel preparation decreases surgical site infection (SSI) and anastomotic leak (AL). Methods. Elective colectomies from the National Surgical Quality Improvement Program colectomy database (2012–2015) were divided by (1) type of bowel preparation: no preparation (NP), mechanical preparation (MP), oral antibiotics (PO), or mechanical and oral antibiotics (PO/MP); and (2) type of colonic resection: right, left, or segmental colectomy. Univariate and multivariate analyses identified predictors of SSI and AL, and their risk‐adjusted incidence was determined by logistic regression. Results. When analyzed as the odds ratio compared with NP, the PO and PO/MP groups were associated with a decrease in SSI (PO = 0.70 [0.55–0.88] and PO/MP = 0.47 [0.42–0.53]; P < .01). Use of PO/MP was associated with a decrease in SSI across all types of resections (right colectomy = 0.40 [0.33–0.50], left colectomy = 0.57 [0.47–0.68], and segmental colectomy = 0.43 (0.34–0.54); P < .01). Similarly, use of PO/MP was associated with a decrease in AL in left colectomy = 0.50 ([0.37–0.69]; P < .01) and segmental colectomy = 0.53 ([0.36–0.80]; P < .01). Conclusion. Mechanical bowel preparation with oral antibiotics is the preferred preoperative preparation strategy in elective colectomy because of decreased incidence of SSI and AL.

Variability in blood transfusions after pancreaticoduodenectomy: A national analysis of the University HealthSystem Consortium

Background: Variability in blood use after pancreaticoduodenectomy and the associated impact on readmission, mortality, and cost is not well understood at the national level. Methods: The University HealthSystem Consortium database was queried for all pancreaticoduodenectomies performed between the years 2011–2013 (n=9,582). Patients were grouped according to transfusion requirements into none (0 units, 64%), low (1–2 units, 15%), medium (3–5 units, 13%), and high (>5 units, 8%). Multivariable analyses were used to determine predictors of increased transfusions, readmission, in‐hospital mortality, and cost. Results: Of the patients undergoing pancreaticoduodenectomy, 36% received blood perioperatively. Patients with high transfusion requirements were less often white, more often male, and had a higher severity of illness (all P < .01). High transfusion requirements correlated with higher readmission rates (OR 1.23, P=.03), cost (RR 1.84, P < .01), length of stay (18 vs. 13 vs. 10 vs. 8 days, P < .01), and in‐hospital mortality (12.5% vs. 3.1% vs. 0.5% vs. 0.4%, P < .01). Higher‐volume surgeons demonstrated lower transfusion requirements (OR 0.61, P < .01). Conclusion: Significant variability exists nationally in transfusion practices for patients undergoing pancreaticoduodenectomy, which may be driven most by severity of illness and surgeon volume. Efforts to reduce such variability could lead to improved outcomes and healthcare cost savings.

Narrowing of the surgical resident operative experience: A 27-year analysis of national ACGME case logs

Background: Although overall operative volume has remained stable since the implementation of duty hours, more detailed analyses suggest shifts in the resident operative experience. Understanding these differences allows educators to better appreciate the impact of the current training environment on resident preparation for practice. Methods: National Accreditation Council for Graduate Medical Education case logs from 1990 to 2016 were reviewed. Statistical analysis was performed using analysis of variance and linear regression analysis. Results: Over the study period there was no change in total major cases. Subcategory analysis revealed an increase in skin and soft tissue, alimentary tract, abdomen, and endocrine with a concurrent decrease in breast, pediatrics, and trauma. During this time, residents completed fewer cases during their chief year, operated more during non‐chief years, taught fewer operations, and assisted in minimal cases. Finally, a decrease in the variability of overall operative volume for total major cases was found as a result of 90th and 10th percentiles converging toward the median. Conclusion: Although total major cases logged by residents have remained stable, the operative experience of general surgery residents has narrowed significantly. Residents are operating earlier and performing fewer teaching and first assistant cases. Surgical educators must look beyond total case numbers and be aware of these changes to ensure all residents achieve technical competency on graduation.

The Surgeon’s Role in Treating Chronic Pancreatitis and Incidentally Discovered Pancreatic Lesions

Chronic pancreatitis and incidentally discovered pancreatic lesions present significant diagnostic and therapeutic challenges for surgeons. While both decompressive and resection procedures have been described for treatment of chronic pancreatitis, optimal management must be tailored to each patient’s individual disease characteristics, parenchymal morphology, and ductal anatomy. Surgeons should strive to achieve long-lasting pain relief while preserving native pancreatic function. For patients with incidentally discovered pancreatic lesions, differentiating benign, pre-malignant, and malignant lesions is critical as earlier treatment is thought to result in improved survival. The purpose of this evidence-based manuscript is to review the presentation, workup, surgical management, and associated outcomes for patients with chronic pancreatitis or incidentally discovered solid and cystic lesions of the pancreas.