Meta-analysis of internal herniation after gastric bypass surgery.

Background The aim of this study was to provide a systematic and quantitative summary of the association between laparoscopic Roux-en-Y gastric bypass (LRYGB) and the reported incidence of internal herniation (IH). The route of the Roux limb and closure of mesenteric and/or mesocolonic defects are described as factors of influence. Methods MEDLINE, Embase, the Cochrane Library and Web of Science were searched for relevant literature, references and citations according to the PRISMA statement. Two independent reviewers selected studies that evaluated incidence of IH after LRYGB and possible techniques for prevention. Data were pooled by route of the Roux limb and closure/non-closure of the mesenteric and/or mesocolonic defects. Results Forty-five articles included data on 31 320 patients. Lowest IH incidence was in the antecolic group, with closure of all defects (1 per cent; P < 0·001), followed by the antecolic group, with all defects left open and the retrocolic group with closure of the mesenteric and mesocolonic defect (both 2 per cent; P < 0·001). The incidence of IH was highest in the antecolic group, with closure of the jejunal defect, and in the retrocolic group, with closure of all defects (both 3 per cent). Conclusion The present systematic review includes a random-effects meta-analysis. The antecolic procedure, with closure of both the mesenteric and Petersen defects, has the lowest internal herniation incidence following laparoscopic Roux-en-Y gastric bypass.