title: High frequency of internal hernias after Roux-en-Y gastric bypass.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors: Bariatric Surgery Unit, Digestive Surgery Department, School of Medicine, Pontificia Universidad Católica de Chile, Marcoleta 350, Patio Interior, Santiago, Chile, nfquezada@gmail.com.
authors: Nicolás
authors: N
authors: Quezada
authors: Felipe
authors: F
authors: León
authors: Alex
authors: A
authors: Jones
authors: Julián
authors: J
authors: Varas
authors: Ricardo
authors: R
authors: Funke
authors: Fernando
authors: F
authors: Crovari
authors: Alejandro
authors: A
authors: Raddatz
authors: Gustavo
authors: G
authors: Pérez
authors: Alex
authors: A
authors: Escalona
authors: Camilo
authors: C
authors: Boza
mesh_terms: D015746:Abdominal Pain / Q000453:epidemiology / Q000209:etiology; D000328:Adult; D002763:Cholecystectomy / Q000009:adverse effects / Q000706:statistics & numerical data; D005260:Female; D015390:Gastric Bypass / Q000009:adverse effects* / Q000379:methods / Q000706:statistics & numerical data; D046449:Hernia, Abdominal / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007415:Intestinal Obstruction / Q000453:epidemiology / Q000209:etiology; D010535:Laparoscopy / Q000379:methods; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000453:epidemiology* / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology*; D015995:Prevalence; D012189:Retrospective Studies; D055815:Young Adult
references: Obes Surg. 2013 Aug;23(8):1273-80
references: 23462859
references: Obes Surg. 2009 May;19(5):549-52
references: 18931883
references: Obes Surg. 2003 Aug;13(4):596-600
references: 12935361
references: Surg Obes Relat Dis. 2007 Jul-Aug;3(4):423-7
references: 17544923
references: Arch Surg. 2003 Sep;138(9):957-61
references: 12963651
references: Surg Endosc. 2011 May;25(5):1594-8
references: 21072668
references: Ann Surg. 2000 Oct;232(4):515-29
references: 10998650
references: Surg Obes Relat Dis. 2005 Nov-Dec;1(6):543-8
references: 16925288
references: Surg Endosc. 2005 Jan;19(1):34-9
references: 15529196
references: Obes Surg. 1996 Dec;6(6):485-493
references: 10729897
references: Obes Surg. 2007 Dec;17(12):1563-6
references: 18004631
references: Arch Surg. 2000 Sep;135(9):1029-33; discussion 1033-4
references: 10982506
references: Obes Surg. 2006 Nov;16(11):1482-7
references: 17132415
references: Obes Surg. 2003 Jun;13(3):350-4
references: 12841892
references: AJR Am J Roentgenol. 2002 Dec;179(6):1437-42
references: 12438032
references: Obes Surg. 2005 Jun-Jul;15(6):766-70; discussion 770
references: 15978143
references: Obes Surg. 2007 Dec;17(12):1549-54
references: 18040752
references: Cir Esp. 2007 Aug;82(2):77-88
references: 17785141
references: Obes Surg. 2011 Dec;21(12):1822-7
references: 21656166