A Randomized Trial Comparing Skin Antiseptic Agents at Cesarean Delivery

Abstract

Background: Preoperative skin antisepsis has the potential to decrease the risk of surgical-site infection. However, evidence is limited to guide the choice of antiseptic agent at cesarean delivery, which is the most common major surgical procedure among women in the United States.

Methods: In this single-center, randomized, controlled trial, we evaluated whether the use of chlorhexidine-alcohol for preoperative skin antisepsis was superior to the use of iodine-alcohol for the prevention of surgical-site infection after cesarean delivery. We randomly assigned patients undergoing cesarean delivery to skin preparation with either chlorhexidine-alcohol or iodine-alcohol. The primary outcome was superficial or deep surgical-site infection within 30 days after cesarean delivery, on the basis of definitions from the Centers for Disease Control and Prevention.

Results: From September 2011 through June 2015, a total of 1147 patients were enrolled; 572 patients were assigned to chlorhexidine-alcohol and 575 to iodine-alcohol. In an intention-to-treat analysis, surgical-site infection was diagnosed in 23 patients (4.0%) in the chlorhexidine-alcohol group and in 42 (7.3%) in the iodine-alcohol group (relative risk, 0.55; 95% confidence interval, 0.34 to 0.90; P=0.02). The rate of superficial surgical-site infection was 3.0% in the chlorhexidine-alcohol group and 4.9% in the iodine-alcohol group (P=0.10); the rate of deep infection was 1.0% and 2.4%, respectively (P=0.07). The frequency of adverse skin reactions was similar in the two groups.

Conclusions: The use of chlorhexidine-alcohol for preoperative skin antisepsis resulted in a significantly lower risk of surgical-site infection after cesarean delivery than did the use of iodine-alcohol. (Funded by the National Institutes of Health and Washington University School of Medicine in St. Louis; ClinicalTrials.gov number, NCT01472549.).

Figure 1

Randomization and Follow-up of Study Participants.

Figure 2. Risk of Surgical-Site Infection in Subgroups

The analyses were performed according to the intention-to-treat principle. Four subgroup analyses were prespecified: scheduled versus unscheduled cesarean delivery, obese (body-mass index [the weight in kilograms divided by the square of the height in meters], ≥30) versus nonobese, subcuticular suture versus staple closure, and presence versus absence of chronic medical condition (diabetes, chronic hypertension, or renal disease). One subgroup analysis was post hoc (diabetes vs. no diabetes). Estimates for the relative effect of chlorhexidine–alcohol versus iodine–alcohol on the risk of surgical-site infection in each subgroup are presented as relative risks with 95% confidence intervals. P values for interaction are from the Mantel–Haenszel test of homogeneity. Data on the skin-closure type were missing for one patient in the iodine–alcohol group. The arrow indicates that the lower limit of the 95% confidence interval is less than 0.2.