Povidone iodine noninferior to chlorhexidine gluconate for preventing surgical site infections

Povidone iodine compares favourably with chlorhexidine gluconate in terms of reducing the incidence of surgical site infections (SSIs) after cardiac or abdominal surgical procedures, according to a study.

A total of 3,360 patients (mean age 65.0 years, 32.9 percent female), of which 65 percent were undergoing cardiac procedures and 35 percent were undergoing abdominal procedures, participated in the study. These patients were randomly assigned to receive preoperative skin antisepsis with either povidone iodine (n=1,598) or chlorhexidine gluconate (n=1,762), each formulated in alcohol. Disinfectants and skin application processes were standardized and followed published protocols.

The primary outcome of SSI within 30 days after abdominal surgery and within 1 year after cardiac surgery was compared between the treatment arms, with a noninferiority margin of 2.5 percent used. SSIs were also evaluated according to depth of infection and type of surgery.

SSIs occurred in 5.1 percent of patients in the povidone iodine group and in 5.5 percent of those in the chlorhexidine gluconate group (unadjusted relative risk [RR], 0.92, 95 percent confidence interval [CI], 0.69–1.23), establishing the noninferiority of povidone iodine.

When stratified by type of surgical procedure, SSI rates were likewise similar between the treatment groups. In cardiac procedures, SSIs occurred in 4.2 percent of patients with povidone iodine and in 3.3 percent with chlorhexidine gluconate (RR, 1.26, 95 percent [CI], 0.82–1.94). In abdominal procedures, SSIs occurred in 6.8 percent of patients with povidone iodine and in 9.9 percent with chlorhexidine gluconate (RR, 0.69, 95 percent CI, 0.46–1.02).