Kalyana C. Nandipati

Resident Participation in Index Laparoscopic General Surgical Cases: Impact of the Learning Environment on Surgical Outcomes

BACKGROUND The NSQIP database enables measurement of postoperative outcomes across a spectrum of practice settings. This allows for observations about potential effects of resident participation in surgical care during training. STUDY DESIGN We queried the NSQIP database for 6 index laparoscopic surgical procedures performed during 2005-2008. Selected procedures require varying skill level (eg, appendectomy, cholecystectomy, gastric bypass, fundoplication, colectomy, and inguinal hernia), and 79,720 cases were identified. Preoperative, operative, and postoperative outcomes for each procedure were tabulated. Operative and postoperative outcomes assessed included operative time, hospital length of stay, mortality, morbidity, and return to the operating room. Initial analysis compared cases done with a resident present with cases done without residents. Subset analysis was done to determine possible differences in outcomes based on the level of resident participating, divided into Junior (PGY1-2), Senior (PGY3-5), or Fellow (PGY>5). Groups were scrutinized for both clinical and statistical differences. RESULTS Preoperative characteristics were similar between groups. Operative times were 20% to 47% longer with resident participation, with bigger differences seen in more basic procedures. Mortality and return to the operating room were not clinically different between the groups. Morbidity rates were higher in all procedures with resident participation. More senior residents were associated with longer operative times, without adverse impact on outcomes. CONCLUSIONS Resident participation increases operative times for laparoscopic surgery considerably. Morbidity is statistically higher with resident participation but differences are unlikely to be clinically significant. Resident participation is a surrogate for the learning environment. These findings provide impetus for additional development of training techniques that occur outside the operating room.

Protein kinases: mechanisms and downstream targets in inflammation-mediated obesity and insulin resistance

Obesity-induced low-grade inflammation (metaflammation) impairs insulin receptor signaling. This has been implicated in the development of insulin resistance. Insulin signaling in the target tissues is mediated by stress kinases such as p38 mitogen-activated protein kinase, c-Jun NH2-terminal kinase, inhibitor of NF-kB kinase complex β (IKKβ), AMP-activated protein kinase, protein kinase C, Rho-associated coiled-coil containing protein kinase, and RNA-activated protein kinase. Most of these kinases phosphorylate several key regulators in glucose homeostasis. The phosphorylation of serine residues in the insulin receptor and IRS-1 molecule results in diminished enzymatic activity in the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. This has been one of the key mechanisms observed in the tissues that are implicated in insulin resistance especially in type 2 diabetes mellitus (T2-DM). Identifying the specific protein kinases involved in obesity-induced chronic inflammation may help in developing the targeted drug therapies to minimize the insulin resistance. This review is focused on the protein kinases involved in the inflammatory cascade and molecular mechanisms and their downstream targets with special reference to obesity-induced T2-DM.

Increased expression of triggering receptor expressed on myeloid cells-1 in the population with obesity and insulin resistance

Triggering receptor expressed on myeloid cells (TREM)−1 has recently been recognized as one of the potent amplifiers of acute and chronic inflammation. However, the exact role of TREM‐1 in regard to insulin insensitivity is unknown.

Immunological and molecular basis of nonalcoholic steatohepatitis and nonalcoholic fatty liver disease

The prevalence of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) is rising worldwide with the increasing incidence of obesity, Type 2 diabetes mellitus and metabolic syndrome. NASH is currently one of the most common indications of liver transplantation in the United States. The immune system plays a major role in the pathogenesis of NAFLD/NASH. The metabolic changes, associated with obesity and metabolic syndrome, induce immunological responses resulting in NAFLD and further aggravation of the metabolic derangement in a feed-forward loop. Genetic and endocrine factors modulate the immunological and metabolic responses and determine the pathophysiological features of NAFLD. Histologically, NAFLD is a spectrum that ranges from simple hepatic steatosis to severe steatohepatitis, liver cirrhosis and/or hepatocellular carcinoma. Liver cirrhosis and hepatocellular carcinoma are responsible for the morbidity and mortality of the disease. This article is a critical evaluation of our current knowledge of the immunological and molecular basis of the disease.

589 Reoperative Intervention in Patients With Mesh At Hiatus Is Associated With High Morbidity and High Incidence of Esophageal Resection - Single Center Experience

Background: Increasing use of mesh for hiatus repair during anti-reflux surgery has been reported. Re-operative intervention with previously placed mesh is technically more challenging. The aim of this study is to present a single Center experience with reoperative intervention in patients with previous mesh at hiatus and outcomes in this subset of patients. Methods: After Institutional review board approval prospectively maintained database was retrospectively queried to identify patients who underwent re-operative intervention between 2003 to 2012 and had mesh placed at a previous hiatal hernia procedure. Patient charts were reviewed and variables collected included demographics, indications, operative details (initial and reoperative) and postoperative complications. Results: Twenty-six patients met inclusion criteria and form the cohort for the study. There were 14 females with a mean age of 58.3 + 29.2 years. Synthetic mesh was placed in 15 (58%) patients, while the remaining 11 had bio-prosthetic mesh. Mean duration of re-operative intervention since the last surgery was 22 (1-52) months. Dysphagia (57%) was the most common presentation while 4 patients had mesh erosion. Recurrent hiatus hernia (2 to 7 cm) was noted in 16 (62%) patients. Nine patients (35%) underwent redo fundoplication, 8 (31%) were converted to Roux en Y gastrojejunostomy, 3 (12%) underwent distal esophagectomy with esophago-jejunostomy, 5 (19%) had subtotal esophagectomy with gastric pull-up and one patient underwent substernal gastric pull-up for esophageal bypass with interval esophagectomy. The mean operative time was 250 + 70.1 min, the median blood loss was 150 ml (50-1650 ml). Reoperative intervention was performed with laparoscopic approach in 50% (13/26) of the patients, laparoscopy converted to laparotomy in 12% (3/26) of the patients, laparotomy was performed in 34% (9/26) and thoracotomy was performed in 1 patient. There was no post-operative mortality. Major complications were noted in 6 patients. Mean ICU stay was 6 days and hospital stay was 14 days. Conclusion: Reoperative intervention in patients with mesh at hiatus is associated with a high (.35 %) need for esophageal resection. More than half the patients also had a recurrent hiatal hernia. Caution is advised in liberal use of mesh for hiatoplasty.