Chlorhexidine Gluconate Versus Povidone-Iodine as Vaginal Preparation Antiseptics Prior to Cesarean Delivery

Patients who are planning cesarean will be recruited and consented for study participation at time of admission to labor and delivery.

Patients undergoing cesarean who meet inclusion/exclusion criteria will be randomized to one of two surgical preparations as follows: 1. Chlorhexidine gluconate (CHG); or, 2. Povidone-iodine scrub. Randomization will be performed by the consenting surgeon (listed as key personnel) after the patient has arrived into the operating room for cesarean. To establish baseline bacterial load, a qualitative BAL culture will be collected prior to the vaginal preparations. Pre-operative surgical site antisepsis will be performed according to randomization. All other surgical practices will remain at the surgeon's discretion according to standard of care at Metro Health Hospital.

At the completion of the cesarean, it is standard practice to perform a manual evacuation of blood clots from the lower uterine segment. The study culture will be obtained by the consenting surgeon immediately prior to manual evacuation. The cultures will then be sent to the lab for determination of total bacterial load of the vaginal area. The lab will be blinded toward which type of vaginal prep was used. Total colony count will be determined by certified lab personnel by adding all counts regardless of bacteria type. A secondary chart review will be performed by the investigator within 30 days of the postoperative period to evaluate for length of hospital stay, pain level, blood loss, any additional antibiotics received postoperatively, and the development of post-operative infection in subjects up to 30 days after discharge.

The research project will take place over a 12-month period of time at Metro Health Hospital. In review of Metro Health Labor and Delivery statistics for scheduled cesarean sections performed in 2016, an average of 18.8 were performed a month, giving a total of approximately 226 in a one-year period. Based on the research study published by Culligan, Kubik, Murphy, et al. comparing the two vaginal preparations for vaginal hysterectomy, an estimated sample size was calculated. Using the 90 minute colony counts of 20,472 (40,058) vs 1,221 (2,857), and using an alpha of .05 and power of 80% investigator found the sample size for each group should be at least 27. This sample size (27 X 2 groups) is very close to the sample size (50) in the Culligan experiment. In an attempt to ensure the most clinically significant, investigators anticipate screening between 70-100 patients with approximately 70-80% participation.

Analysis will be performed by the investigators for completeness, accuracy, strict adherence to study protocol, safety, and statistical significance. The investigators are also subject to periodic audits by the Institutional Review Board (IRB).

Inclusion criteria

• Scheduled low transverse cesarean section (can be primary or repeat)
• Term gestation ≥ 37 weeks

Exclusion criteria

• Allergy to either antiseptic
• Rupture of amniotic membranes
• Preterm gestation
• Active labor
• Emergency or unscheduled cesarean sections
• Infection diagnosis on admission
• Vaginal infection or any treatment of vulvovaginitis in prior 7 days
• Patients under the age of 18 years