High Frequency of Internal Hernias After Roux-en-Y Gastric Bypass

Internal hernias (IH) after Roux-en-Y gastric bypass (RYGB) are a serious concern among surgeons and are often under-diagnosed due to heterogeneity of clinical manifestations. Our aim is to assess the frequency of IH after a RYGB in symptomatic and asymptomatic patients. Retrospective analysis of our bariatric surgery unit's database between 2001 and 2013 is obtained. Patients are surgically explored after RYGB due to acute bowel obstruction (ABO), intermittent abdominal pain (IAP), or being asymptomatic (during an elective cholecystectomy) in whom anatomical presence of IH was established. Also, we compared patients with retrocolic and antecolic technique. Statistical analysis with non-parametric tests and chi-square are used. Of the patients, 3,656 submitted to RYGB during this period, 81.9 % (2,993) by laparoscopy and 26.3 % (963) with retrocolic technique. Of the patients, 130 (3.5 %) were surgically explored due to ABO, 27 patients (0.7 %) due to IAP, and 93 patients (2.5 %) submitted to an elective cholecystectomy with exploration for IH. IH was present in 75 % of the obstructed patients, and in 69 %, it was the cause of obstruction. Patients with IAP showed 59 % of IH, but only 15 % have herniated bowel. In asymptomatic patients, 25 % showed IH and none of them have herniated bowel. Retrocolic technique showed a higher risk of whole causes of ABO and IH than the antecolic technique, with a relative risk of 1.53 (1.07-2.17) and 1.62 (1.06-2.47), respectively. A high frequency of IH exists in all operated patients of this series. All members of the bariatric team should be aware of the symptoms related to IH and actively pursue it during follow-up.