Fast pouch emptying, delayed small intestinal transit, and exaggerated gut hormone responses after Roux-en-Y gastric bypass.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) causes extensive changes in gastrointestinal anatomy and leads to reduced appetite and large weight loss, which partly is due to an exaggerated release of anorexigenic gut hormones. METHODS: To examine whether the altered passage of foods through the gastrointestinal tract after RYGB could be responsible for the changes in gut hormone release, we studied gastrointestinal motility with a scintigraphic technique as well as the secretion of the gut hormones glucagon-like peptide (GLP)-1 and peptide YY3-36 (PYY3-36 ) in 17 patients>1 year after RYGB and in nine healthy control subjects. KEY RESULTS: At meal completion, a smaller fraction of liquid and solid radiolabeled marker was retained in the pouch of RYGB patients than in the stomach of control subjects (P = 0.002 and P < 0.001, respectively). Accordingly, pouch emptying in patients was faster than gastric emptying in control subjects (P < 0.001 and P = 0.004, respectively liquid and solid markers). For the solid marker, small intestinal transit was slower in patients than control subjects (P = 0.034). Colonic transit rate did not differ between the groups. GLP-1 and PYY3-36 secretion was increased in patients compared to control subjects and fast pouch emptying of the liquid marker was associated with high gut hormone secretion. CONCLUSIONS & INFERENCES: After RYGB, the bulk of foods pass without hindrance into the small intestine, while the small intestinal transit is prolonged. The rapid exposure of the gut epithelium contributes to the exaggerated release of GLP-1 and PYY3-36 after RYGB.

Changes in gastrointestinal hormone responses, insulin sensitivity, and beta-cell function within 2 weeks after gastric bypass in non-diabetic subjects.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) surgery causes profound changes in secretion of gastrointestinal hormones and glucose metabolism. We present a detailed analysis of the early hormone changes after RYGB in response to three different oral test meals designed to provide this information without causing side effects (such as dumping). METHODS: We examined eight obese non-diabetic patients before and within 2 weeks after RYGB. On separate days, oral glucose tolerance tests (25 or 50 g glucose dissolved in 200 mL of water) and a liquid mixed meal test (200 mL 300 kcal) were performed. We measured fasting and postprandial glucose, insulin, C-peptide, glucagon, total and intact glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-2 (GLP-2), peptide YY(3-36) (PYY), cholecystokinin (CCK), total and active ghrelin, gastrin, somatostatin, pancreatic polypeptide (PP), amylin, leptin, free fatty acids (FFA), and registered postprandial dumping. Insulin sensitivity was measured by homeostasis model assessment of insulin resistance. RESULTS: Fasting glucose, insulin, ghrelin, and PYY were significantly decreased and FFA was elevated postoperatively. Insulin sensitivity increased after surgery. The postprandial response increased for C-peptide, GLP-1, GLP-2, PYY, CCK, and glucagon (in response to the mixed meal) and decreased for total and active ghrelin, leptin, and gastrin, but were unchanged for GIP, amylin, PP, and somatostatin after surgery. Dumping symptoms did not differ before and after the operation or between the tests. CONCLUSIONS: Within 2 weeks after RYGB, we found an increase in insulin secretion and insulin sensitivity. Responses of appetite-regulating intestinal hormones changed dramatically, all in the direction of reducing hunger.

Complications of fractures of the femoral neck.

The results of a series of 82 medial femoral neck fractures are presented. Complications arose in 34% of 24 non-operated impacted fractures (17% redisplacement, 17% necrosis of the femoral head). 58 patients were treated with a sliding screw plate device (Zimmer). The Garden stage I and II fractures united uneventfully. Out of a total of 52 Garden stage III and IV fractures, 14 (27%) had to be reoperated with total hip arthroplasty, due to redisplacement or necrosis of the femoral head. All redisplacements occurred in cases of unsuccessful reduction, indicating that quality of reduction is the prime determinant with regard to redisplacement. As all Garden stage I and II fractures, and 73% of the Garden stage III and IV fractures united, the material points at the gliding screw plate device as a most recommendable treatment in femoral neck fractures.