Does the non-absorbable suture closure of the jejunal mesenteric defect reduce the incidence and severity of internal hernias after laparoscopic Roux-en-Y gastric bypass?

Internal hernias (IH) are frequent complications after laparoscopic Roux-en-Y gastric bypass (LRYGB). Closure of the jejunal mesenteric and the Petersen defect reduces IH incidence in prospective and retrospective trials. This study investigates whether closing the jejunal mesenteric space alone by non-absorbable suture and splitting the omentum can be beneficial to prevent IH after LRYGB. Observational cohort study of 785 patients undergoing linear LRYGB including omental split at a single institution, with 493 patients without jejunal mesenteric defect closure and 292 patients with closure by non-absorbable suture, and a minimal follow-up of 2 years. Patients were assessed for appearance and severity of IH. Additionally, open mesenteric gaps without herniated bowel as well as early obstructions due to kinking of the entero-enterostomy (EE) were explored. Through primary mesenteric defect closure, the rate of manifest jejunal mesenteric and Petersen IH could be reduced from 6.5 to 3.8%, but without reaching statistical significance. The most common location for an IH was the jejunal mesenteric space, where defect closure during primary surgery reduced the rate of IH from 5.3 to 2.4%. Higher weight loss seemed to increase the risk of developing an IH. The closure of the jejunal mesenteric defect by non-absorbable suture may reduce the rate of IH at the jejunal mesenteric space after LRYGB. However, the beneficial effect in our collective is smaller than expected, particularly in patients with good weight loss. The Petersen IH rate remained low by consequent T-shape split of the omentum without suturing of the defect.