Cesarean delivery is now the most commonly performed major operation in hospitals across the United States. Approximately 30% of the 4 million deliveries that occur each year are by cesarean. Endometritis and wound infection (superficial and deep surgical site infection) are the most common postoperative complications of cesarean delivery. These 2 infections usually can be treated in a straightforward manner with antibiotics or surgical drainage. In some cases, however, they can lead to serious sequelae, such as pelvic abscess, septic pelvic vein thrombophlebitis, and wound dehiscence/evisceration, thereby prolonging the patient’s hospitalization and significantly increasing medical expenses.
Accordingly, in the past 50 years many investigators have proposed various specific measures to reduce the risk of postcesarean infection. In this article, we critically evaluate 2 of these major interventions: methods of skin preparation and administration of prophylactic antibiotics. In part 2 of this series next month, we will review the evidence regarding preoperative bathing with an antiseptic, preoperative vaginal cleansing with an antiseptic solution, methods of placental extraction, closure of the deep subcutaneous layer of the abdomen, and closure of the skin.
CASE Cesarean delivery required for nonprogressing labor
A 26-year-old obese primigravid woman, body mass index (BMI) 37 kg m2, at 40 weeks’ gestation has been in labor for 20 hours. Her membranes have been ruptured for 16 hours. Her cervix is completely effaced and is 7 cm dilated. The fetal head is at −1 cm station. Her cervical examination findings have not changed in 4 hours despite adequate uterine contractility documented by intrauterine pressure catheter. You are now ready to proceed with cesarean delivery, and you want to do everything possible to prevent the patient from developing a postoperative infection.
What are the best practices for postcesarean infection prevention in this patient?
Adequate preoperative skin preparation is an important first step in preventing post‑ cesarean infection.
How should you prepare the patient’s skin for surgery?
Two issues to address when preparing the abdominal wall for surgery are hair removal and skin cleansing. More than 40 years ago, Cruse and Foord definitively answered the question about hair removal.1 In a landmark cohort investigation of more than 23,000 patients having many different types of operative procedures, they demonstrated that shaving the hair on the evening before surgery resulted in a higher rate of wound infection than clipping the hair, removing the hair with a depilatory cream just before surgery, or not removing the hair at all.
Three recent investigations have thoughtfully addressed the issue of skin cleansing. Darouiche and colleagues conducted a prospective, randomized, multicenter trial comparing chlorhexidine-alcohol with povidone-iodine for skin preparation before surgery.2 Their investigation included 849 patients having many different types of surgical procedures, only a minority of which were in obstetric and gynecologic patients. They demonstrated fewer superficial wound infections in patients in the chlorhexidine-alcohol group (4.2% vs 8.6%, P = .008). Of even greater importance, patients in the chlorhexidine-alcohol group had fewer deep wound infections (1% vs 3%, P = .005).
Ngai and co-workers recently reported the results of a randomized controlled trial (RCT) in which women undergoing nonurgent cesarean delivery had their skin cleansed with povidone-iodine with alcohol, chlorhexidine with alcohol, or the sequential combination of both solutions.3 The overall rate of surgical site infection was just 4.3%. The 3 groups had comparable infection rates and, accordingly, the authors were unable to conclude that one type of skin preparation was superior to the other.
The most informative recent investigation was by Tuuli and colleagues, who evaluated 1,147 patients having cesarean delivery assigned to undergo skin preparation with either chlorhexidine-alcohol or iodine-alcohol.4 Unlike the study by Ngai and co-workers, in this study approximately 40% of the patients in each treatment arm had unscheduled, urgent cesarean deliveries.3,4 Overall, the rate of infection in the chlorhexidine-alcohol group was 4.0% compared with 7.3% in the iodine-alcohol group (relative risk [RR], 0.55; 95% confidence interval [CI], 0.34–0.90, P = .02).
What the evidence says
Based on the evidence cited above, we advise removing hair at the incision site with clippers or depilatory cream just before the start of surgery. The abdomen should then be cleansed with a chlorhexidine-alcohol solution (Level I Evidence, Level 1A Recommendation; TABLE).