title: Trends in internal hernia incidence after laparoscopic Roux-en-Y gastric bypass.
abstract: BACKGROUND
  Internal hernia is a known complication after gastric bypass, especially when performed laparoscopically. The aim of this study was to see when internal hernias occur in relation to weight loss and time course after surgery. Furthermore, we wish to examine the impact of Roux limb positioning ante- versus retrocolic and whether switching to running versus interrupted closure of the mesenteric defects created at surgery made any difference.
  
  
  METHODS
  A retrospective chart review was performed of all patients undergoing laparoscopic Roux-en-Y gastric bypass surgery (LRYGB) who developed symptomatic internal hernia requiring operative intervention between January 1, 2000 and September 15, 2006.
  
  
  RESULTS
  Fifty-four internal hernias occurred in 2,572 patients, an incidence of 2.1%. The site of internal hernias varied: 25 (1%), transverse mesocolon; 22 (0.8%), enteroenterostomy; 7 (0.3%), Peterson's space. The mean time to intervention for an internal hernia repair was 413 +/- 46 days and average % excess body weight loss (%EBWL) in this period was 59 +/- 3.3. Subgroup analysis demonstrates internal hernia incidence to be 2 in 357 (0.6%) in antecolic Roux versus 52 in 2,215 (2.4%) in retrocolic Roux limb (odds ratio = 4, P < 0.05). Continuous closure versus interrupted stitching of mesenteric defects does not seem to alter the incidence of internal hernias.
  
  
  CONCLUSIONS
  This study demonstrates that the majority of internal hernias occur after a significant (>50%) EBWL. Furthermore, the antecolic approach is associated with a much reduced incidence of internal hernia.
authors.affiliation: Department of Bariatric Surgery, University of Rochester Medical Center, Highland Hospital, 1000 South Avenue, Rochester, NY 14620, USA. ahmed_ahmed@urmc.rochester.edu
authors.forename: Ahmed R
authors.initials: AR
authors.lastname: Ahmed
authors.forename: Gretchen
authors.initials: G
authors.lastname: Rickards
authors.forename: Syed
authors.initials: S
authors.lastname: Husain
authors.forename: Joseph
authors.initials: J
authors.lastname: Johnson
authors.forename: Thad
authors.initials: T
authors.lastname: Boss
authors.forename: William
authors.initials: W
authors.lastname: O'Malley
mesh_terms: D000328:Adult; D000713:Anastomosis, Roux-en-Y / Q000379:methods; D005260:Female; D015390:Gastric Bypass / Q000379:methods; D006547:Hernia / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D010535:Laparoscopy; D008297:Male; D008643:Mesentery / Q000473:pathology; D008646:Mesocolon / Q000473:pathology; D009767:Obesity, Morbid / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology*; D012189:Retrospective Studies; D013536:Suture Techniques; D015431:Weight Loss