title: Can technical factors explain the volume-outcome relationship in gastric bypass surgery?
abstract: BACKGROUND
  The existence of a relationship between surgeon volume and patient outcome has been reported for different complex surgical operations. This relationship has also been confirmed for patients undergoing Roux-en-Y gastric bypass (RYGB) in the Longitudinal Assessment of Bariatric Surgery (LABS) study. Despite multiple studies demonstrating volume-outcome relationships, fewer studies investigate the causes of this relationship.
  
  
  OBJECTIVE
  The purpose of the present study is to understand possible explanations for the volume-outcome relationship in LABS.
  
  
  METHODS
  LABS includes a 10-center, prospective study examining 30-day outcomes after bariatric surgery. The relationship between surgeon annual RYGB volume and incidence of a composite endpoint (CE) has been published previously. Technical aspects of RYGB surgery were compared between high and low volume surgeons. The previously published model was adjusted for select technical factors.
  
  
  RESULTS
  High-volume surgeons (>100 RYGBs/yr) were more likely to perform a linear stapled gastrojejunostomy, use fibrin sealant, and place a drain at the gastrojejunostomy compared with low-volume surgeons (<25 RYGBs/yr), and less likely to perform an intraoperative leak test. After adjusting for the newly identified technical factors, the relative risk of CE was .93 per 10 RYGB/yr increase in volume, compared with .90 for clinical risk adjustment alone.
  
  
  CONCLUSIONS
  High-volume surgeons exhibited certain differences in technique compared with low-volume surgeons. After adjusting for these differences, the strength of the volume-outcome relationship previously found was reduced only slightly, suggesting that other factors are also involved.
authors.affiliation: Oregon Weight Loss Surgery, Portland, Oregon. Electronic address: mdsmith2@me.com.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Smith
authors.forename: Emma
authors.initials: E
authors.lastname: Patterson
authors.forename: Abdus S
authors.initials: AS
authors.lastname: Wahed
authors.forename: Steven H
authors.initials: SH
authors.lastname: Belle
authors.forename: Anita P
authors.initials: AP
authors.lastname: Courcoulas
authors.forename: David
authors.initials: D
authors.lastname: Flum
authors.forename: Saurabh
authors.initials: S
authors.lastname: Khandelwal
authors.forename: James E
authors.initials: JE
authors.lastname: Mitchell
authors.forename: Alfons
authors.initials: A
authors.lastname: Pomp
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Pories
authors.forename: Bruce
authors.initials: B
authors.lastname: Wolfe
mesh_terms: D000328:Adult; D004322:Drainage / Q000379:methods; D023381:Endpoint Determination; D005260:Female; D015390:Gastric Bypass / Q000379:methods*; D006801:Humans; D008297:Male; D009765:Obesity / Q000601:surgery*; D010043:Outcome and Process Assessment, Health Care; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D011446:Prospective Studies; D014014:Tissue Adhesives / Q000627:therapeutic use; D014481:United States; D016526:Workload
chemical_list: D014014:Tissue Adhesives