title: Should perioperative supplemental oxygen be routinely recommended for surgery patients? A Bayesian meta-analysis.
abstract: OBJECTIVE
  The purpose of this study is to use updated data and Bayesian methods to evaluate the effectiveness of hyperoxia to reduce surgical site infections (SSIs) and/or mortality in both colorectal and all surgery patients. Because few trials assessed potential harms of hyperoxia, hazards were not included.
  
  
  BACKGROUND
  Use of hyperoxia to reduce SSIs is controversial. Three recent meta-analyses have had conflicting conclusions.
  
  
  METHODS
  A systematic literature search and review were performed. Traditional fixed-effect and random-effect meta-analyses and Bayesian meta-analysis were performed to evaluate SSIs and mortality.
  
  
  RESULTS
  Traditional meta-analysis yielded a relative risk of an SSI with hyperoxia among all surgery patients of 0.84 [95% confidence interval (CI): 0.73-0.97] and 0.84 (95% CI: 0.61-1.16) for the fixed-effect and random-effect models, respectively. The probabilities of any risk reduction in SSIs among all surgery patients were 77%, 81%, and 83% for skeptical, neutral, and enthusiastic priors. The subset analysis of colorectal surgery patients increased the probabilities to 86%, 89%, and 92%. The probabilities of at least a 10% reduction were 57%, 62%, and 68% for all surgery patients and 71%, 75%, and 80% among the colorectal surgery subset.
  
  
  CONCLUSIONS
  There is a moderately high probability of a benefit to hyperoxia in reducing SSIs in colorectal surgery patients; however, the magnitude of benefit is relatively small and might not exceed treatment hazards. Further studies should focus on generalizability to other patient populations or on treatment hazards and other outcomes.
authors.affiliation: Center for Clinical Research and Evidence-Based Medicine, The University of Texas Health Science Center at Houston, TX 77026, USA. Lillian.S.Kao@uth.tmc.edu
authors.forename: Lillian S
authors.initials: LS
authors.lastname: Kao
authors.forename: Stefanos G
authors.initials: SG
authors.lastname: Millas
authors.forename: Claudia
authors.initials: C
authors.lastname: Pedroza
authors.forename: Jon E
authors.initials: JE
authors.lastname: Tyson
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Lally
mesh_terms: D001499:Bayes Theorem; D006801:Humans; D010100:Oxygen / Q000627:therapeutic use*; D019990:Perioperative Care; D017410:Practice Guidelines as Topic; D013530:Surgical Wound Infection / Q000517:prevention & control*
chemical_list: D010100:Oxygen