Diagnosis and management of internal hernias after laparoscopic gastric bypass

Internal hernia is a known complication of laparoscopic Roux-en-Y gastric bypass (LRYGBP). However, no consensus exists regarding optimal diagnostic modality and management. We reviewed the literature and our own experience, and present an algorithm for the diagnosis and management of internal hernia after LRYGBP.

A retrospective review of 290 retrocolic LRYGBPs was performed to identify those who developed postoperative small bowel obstruction due to internal hernia. Demographics, clinical symptoms, radiologic characteristics, and operative outcomes were analyzed to determine clinical and radiological diagnostic accuracy.

Over a 43-month period, 11 out of 290 (3.79%) post-LRYGBP patients with symptoms suggestive of a small bowel obstruction underwent operative exploration. The most common clinical symptoms included intermittent abdominal pain, and/or nausea/vomiting. All patients were initially explored laparoscopically. Etiology of obstructions included internal hernias--6 [at the transverse mesocolon (n = 1), Petersen's space (n = 2), and at the jejunojejunostomy (n = 3)], adhesions (n = 4) and a negative laparoscopy (n = 1). The mean time for development of internal hernias was 13.7 months. Mean loss of BMI units at time of re-operation was 17 kg/m2. Of the 6 patients with internal hernia, 2 (30%) had normal preoperative radiological work-up. On review of the preoperative films by the surgeon, signs of internal herniation were seen in all the patients. Management included initial laparoscopic exploration, lysis of adhesions, reduction of internal hernia and closure of mesenteric defects in all the patients. There were 2 conversions to laparotomy.

Small bowel obstruction in the post-LRYGBP patient is difficult to diagnose, especially when due to an internal hernia. Most patients present with intermittent abdominal pain and/or nausea. The most frequently used radiologic study is CT scan, which is most accurate when reviewed by the bariatric surgeon preoperatively.