Shai Meron Eldar

Bariatric surgery for treatment of obesity

This article focuses on recent trends and outcomes of bariatric surgery. The outcomes discussed include perioperative morbidity and mortality, weight loss, long-term complications and the impact of bariatric surgery on comorbidities, cardiovascular risk and mortality.

Banded Roux-en-Y gastric bypass for the treatment of morbid obesity

BACKGROUND Laparoscopic Roux-en-Y gastric bypass (LRYGB) is the most effective treatment for morbid obesity. The additional benefit of placing a nonadjustable band around the pouch remains to be determined. The objective of this study was to compare outcomes between banded and nonbanded LRYGB patients in a single bariatric center. METHODS A matched cohort analysis was performed between patients who had undergone banded and nonbanded (standard) LRYGB. In the banded bypass cohort, an 8 F, 6.5 cm silastic ring was placed around the proximal gastric pouch. Both cohorts were matched for age, body mass index (BMI), and anastomotic technique. Endpoints included percentage excess weight loss (%EWL), postoperative morbidity, and band-related complications. RESULTS Between January 2007 and July 2010, 134 banded LRYGB were performed (55% female, mean age 45 years). They were compared with a matched cohort of 134 concurrent nonbanded LRYGB patients (67% female, mean age 45.4 years). Mean preoperative BMI was 54.6 and 52.8 kg/m(2), respectively (P = .084). At 24 months postoperatively, the average %EWL was 58.6% in banded bypass patients and 51.4% in the nonbanded group (P = .015). The difference in EWL was more pronounced in super-obese patients than in those with BMI<50 (among super-obese, 57.5% versus 47.6%, P = .003; among those with BMI<50, 62.9% versus 57.9%, P = .406]. There was no difference in early (19.4% versus 19.4%) or late complications (10.4% versus 13.4%, P = .451) between banded and nonbanded LRYGB patients. CONCLUSION Banding the pouch during LRYGB can be performed safely and may provide better weight loss, particularly in super-obese patients. Further prospective and long-term comparative studies of this technique are warranted.

The effect of selective gut stimulation on glucose metabolism after gastric bypass in the Zucker diabetic fatty rat model

BACKGROUND Potential mechanisms underlying the antidiabetic effects of Roux-en-Y gastric bypass (RYGB) include altered nutrient exposure in the gut. The aim of this study was to evaluate the effects of selective gut stimulation on glucose metabolism in an obese diabetic rat model. METHODS Sixteen male Zucker diabetic fatty rats were randomly assigned to 1 of 2 groups: RYGB with gastrostomy tube (GT) insertion into the excluded stomach or a control group with GT insertion into the stomach. An insulin tolerance test (ITT), oral glucose tolerance test (OGTT), and mixed meal tolerance test (MMTT) were performed before and 14-28 days after surgery. A glucose tolerance test via GT (GTT-GT) and MMTT via GT were performed postoperatively. RESULTS Postoperatively, the RYGB group had significant decreases in weight and food intake. Both the ITT and OGTT tests revealed significantly improved glucose tolerance after RYGB. The GTT-GT showed a reversal of the improved glucose tolerance in the RYGB group. In response to meal stimulation, postoperatively, the RYGB group increased glucagon-like peptide 1 (GLP-1) secretion via the oral route and peptide YY secretion by both oral and GT routes. CONCLUSION When foregut exposure to nutrients was reversed after RYGB, the improvement in glucose metabolism was abrogated. This model can be extended to identify the role of gut in glucose homeostasis in type 2 diabetes.

Gastrostomy tube placement in gastric remnant at gastric bypass: a rat model for selective gut stimulation

BACKGROUND Roux-en-Y gastric bypass (RYGB) surgery achieves high remission rates of type 2 diabetes mellitus in obese diabetic patients. It has been hypothesized that the changes in bowel nutrient exposure after RYGB results in altered release of gut hormones and improved glucose homeostasis. Our objective was to assess the feasibility of, and report on, our technique and initial experience with selective gut stimulation in a gastric bypass rat model at an academic medical center in the United States. METHODS We performed RYGB with simultaneous placement of a gastrostomy tube in the excluded gastric remnant in 8 obese Sprague-Dawley rats. A second group of 8 obese Sprague-Dawley rats underwent gastrostomy tube placement without gastric bypass and served as the controls. Each rat was tested for oral glucose tolerance preoperatively. On postoperative days 14 and 28, glucose tolerance was re-evaluated using the oral and gastrostomy tube routes. RESULTS The gastrostomy tubes were successfully inserted in all the rats with no tube-related complications. The area under the curve after oral glucose gavage decreased significantly after gastric bypass (P = .01 at 14 d and P = .003 at 28 d). The gastric remnant glucose gavage after RYGB essentially reversed the effects of surgery on glucose metabolism. The areas under the curve showed no significant differences in the control group between the preoperative and postoperative oral or tube results. CONCLUSION Placing a gastrostomy tube into the gastric remnant at RYGB in a rat model is technically feasible. Our initial findings support the role of duodenal exclusion in improving glucose metabolism after RYGB.