Journal Review in Bariatric Surgery: Mesenteric Defect Closure and Internal Hernia Evaluation/Management

EP. 666Oct. 09, 202329:59
To close or not to close - that is the question!  Internal hernias following bariatric surgery can be a vexing source of delayed postoperative morbidity.  Join Drs. Matthew Martin, Kunoor Jain-Spangler, Adrian Dan, and Vincent Cheng for this EXCELLENT Journal Review in Bariatric Surgery.  

Article #1: Stenberg 2023 - Long-term Safety and Efficacy of Closure of Mesenteric Defects in Laparoscopic Gastric Bypass Surgery
  • Two mesenteric defects are created during Roux-en-Y gastric bypass (RNYGB)
    • Petersen’s Defect
    • Jejuno-jejunostomy mesenteric defect
  •  Consensus does not exist regarding the standard of care for mesenteric defect closure (e.g., closure of one or both defects, material used for closure).  
    • Risks of leaving defects open: internal herniation with or without bowel ischemia
  •  Risks of closing defects
    • Kinking the bowel (especially near the jejunojejunostomy) leading to obstruction 
    • Chronic abdominal pain
  • This article discusses a randomized controlled trial of obese patients undergoing bariatric RNYGB
    • Randomized into two groups: a closure group and a non-closure group 
    • Followed patients for 10 years with 95-96% follow up rate
    • Results analyzed using a Cox proportional hazards regression that included risk factors like BMI, total weight loss at 1 year after surgery, and the other 
    • Highlighted outcomes
      •  Within the first 30 postop days, there was a higher rate of SBO in the closure group (1.3%) compared to the non-closure group (0.2%). This was attributed to kinking of the jejunojejunostomy
      •  After 30 postop days and up to 10 years, reoperation rates for SBO were higher in the non-closure group (14.9%) compared to the closure group (7.8%). This trend was consistent regarding each site of mesenteric defect. 
      • No significant differences between the two groups regarding chronic opioid use as a metric of chronic abdominal pain.
Article #2: Nawas 2022 - The Diagnostic Accuracy of Abdominal Computed Tomography in Diagnosing Internal Herniation Following Roux-en-Y Gastric Bypass Surgery
  • Unless there is an indication to immediately operate on a RNYGB patient in whom internal herniation is suspected, computed tomography (CT) is the recommended diagnostic test
  • This article is a meta-analysis of 20 studies published between 2007 and 2020 that analyzed the accuracy of CT or detecting internal hernias in adult patients who underwent RNYGB for morbid obesity. A collective total of 1,637 patients were included.  
  • Accuracy was determined by comparing diagnostic CT with exploratory surgery or the combination of negative CT and a negative 90 days follow-up
  • Internal herniation was defined as presence of herniated small bowel with or without obstruction or ischemia through a visible opening at the mesenteric defect
  • Results
    • Pooled sensitivity of CT was 82% and specificity was 85%
    • Positive predictive value of CT was 83% and negative predictive value was 86%
  • CT signs with the highest sensitivity (sensitivity of finding) 
    • Venous congestion (79%)
    • Swirl sign (78%) 
    • Mesenteric edema (67%)
  • 15% risk of an internal hernia even with a negative CT scan 
    • In conclusion, CT can provide useful information, but these are just additional data points to consider in the overall evaluation of a patient. Surgeons should still have a low threshold for diagnostic laparoscopy even with negative CT findings
If you liked this episode, check out other bariatric episodes here:

Please visit to access other high-yield surgical education podcasts, videos and more.