Perioperative oxygen supplementation and surgical site infection after cesarean delivery: a randomized trial.

OBJECTIVE: To evaluate whether supplemental perioperative oxygen decreases surgical site wound infections or endometritis. STUDY DESIGN: This was a prospective, randomized trial. Patients who were to undergo cesarean delivery were recruited and randomly allocated to either 30% or 80% oxygen during the cesarean delivery and for 1 hour after surgery. The obstetricians and patients were blinded to the concentration of oxygen used. Patients were evaluated for wound infection or endometritis during their hospital stay and by 6 weeks postpartum. The primary end point was a composite of either surgical site infection or endometritis. RESULTS: Eight hundred thirty-one patients were recruited. Of these, 415 participants received 30% oxygen perioperatively and 416 received 80% oxygen. The groups were well matched for age, race, parity, diabetes, number of previous cesarean deliveries, and scheduled compared with unscheduled cesarean deliveries. An intention-to-treat analysis was used. There was no difference in the primary composite outcome (8.2% in women who received 30% oxygen compared with 8.2% in women who received 80% oxygen, P=.89), no difference in surgical site infection in the two groups (5.5% compared with 5.8%, P=.98), and no significant difference in endometritis in the two groups (2.7% compared with 2.4%, P=.66), respectively. CONCLUSION: Women who received 80% supplemental oxygen perioperatively did not have a lower rate of a surgical site infection or endometritis as compared with women who received 30% supplemental oxygen concentration. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clincaltrials.gov, NCT00876005. LEVEL OF EVIDENCE: I.