Women undergo more cesarean sections each year in the United States than any other major surgery, with the procedure carrying a significant rate of infection at the incision site.
A study from Washington University School of Medicine offers strong guidance on the best way to reduce the infection risk. Rather than prepping patients with iodine-alcohol, the research indicates that chlorhexidine-alcohol is significantly more effective. And the research team argues that the evidence is strong enough to change standard skin-prep practices for C-sections.
“One of the biggest complications of surgery, and of C-sections in particular, is infection,” says first author and obstetrician-gynecologist Methodius Tuuli, MD. An estimated 1.3 million women in the U.S. delivered their babies by C-section in 2013, with surgical-site infections complicating 5 to 12 percent of those deliveries. The average cost of treating those infections in the hospital is $3,500 and can be much higher for severe infections.
The clinical trial included 1,147 women who underwent C-sections at Barnes-Jewish Hospital from 2011 to 2015. They were randomly assigned to receive either the chlorhexidine-alcohol combination before surgery or the iodine-alcohol combination. Of those who were prepped with chlorhexidine, 4 percent developed an infection at the site of the surgery within 30 days of the procedure, compared with 7.3 percent who were prepped with iodine. All other standard procedures for reducing the risk of infection after surgery, including giving preventive antibiotics beforehand, were the same in both groups.
Studies of other types of surgeries also have suggested the superiority of chlorhexidine over iodine in preventing infection. But according to Tuuli, the unique circumstances of a C-section—that bacteria come from both skin and vagina, and that a woman’s immune system is altered during pregnancy— mean the results of these studies may not apply.
In addition, past trials comparing antiseptics before surgery included relatively few participants and often compared a chlorhexidine-alcohol combination with iodine alone. These studies could not determine whether the worse performance of iodine alone was due to the chlorhexidine, the alcohol or the combination.
Although the new study was conducted at only one hospital, the researchers say the patient population was racially diverse and that more than 60 percent received public insurance. Tuuli and his colleagues also pointed out that the superiority of the chlorhexidine-alcohol combination was consistent whether the C-section was scheduled or unscheduled, whether or not the patient was obese, whether staples or sutures were used to close the wound and whether the patient had chronic medical conditions, including diabetes.
Highlighting the significance of the findings, the study’s senior author, George Macones, MD, head of the Department of Obstetrics and Gynecology, says, “There are few circumstances when a single study should change our practice. But based on the biological plausibility and the striking reduction in surgical-site infections with chlorhexidine, this is one of those circumstances.”
Read the study online in The New England Journal of Medicine.