Cesarean wound closure in body mass index 40 or greater comparing suture to staples: a randomized clinical trial

Abstract

Background: Cesarean delivery is the most common major surgical procedure performed in the United States. Women with class III obesity have an increased risk of cesarean delivery and have wound complication rates higher than healthy body mass index counterparts. Available evidence regarding optimal wound closure is lacking specific to the population of women with class III obesity despite a known increased rate of wound complications.

Objective: This study aimed to compare rates of postoperative wound complications among women with class III obesity (body mass index of ≥40 kg/m²) undergoing cesarean delivery with skin closure by either subcuticular suture or surgical staples.

Study design: Patients were randomly assigned to skin closure by nonabsorbable stainless steel surgical staples or subcuticular suture of the surgeon's choice at the time of cesarean delivery at 2 university hospitals. Randomization was stratified for scheduled vs unscheduled cesarean delivery and for the 2 study sites. The primary outcome was the rate of any documented wound complication during the first 6 weeks after delivery. Any predictors of the composite outcome that in univariate analysis had a P<.20 were entered into a forward logistic regression. Sample size was calculated based on published literature and estimating the rate of wound complications within 6 weeks of follow-up at 20% with staples and 10% with sutures. For a power of 0.80 with a 2-tailed of 0.05, a total of 199 participants per group were required.

Results: From September 2015 to May 2019, 232 women were randomized to staples (n=117) or sutures (n=115). Nearing the planned interim analysis, enrollment in the study was concluded administratively owing to low enrollment. With loss to follow-up and exclusions, a total of 90 women were analyzed in each group. In the suture group, one-third was closed with braided suture and two-thirds were closed with monofilament suture. Median staple removal was 5 days postoperatively. Fewer composite wound complications were noted in the surgical staples group than the subcuticular suture group (20.0% vs 27.6%), although this difference was not statistically significant (P≥.5). The rate of surgical site infection was significantly lower in the staples group (10.5% vs 22.7%; P=.041). In the multiple logistic regression, the 3 significant independent predictors of the outcome were body mass index (odds ratio, 1.08; P=.004), scheduled vs unscheduled cesarean delivery (odds ratio, 0.40; P=.018), and study site (odds ratio, 0.36; P=.028).

Conclusion: Surgical staples or subcuticular suture for skin closure at the time of cesarean delivery in women with a body mass index of ≥40 kg/m² resulted in similar composite wound complication rates; however, lower cesarean wound infection rates were noted among wounds closed with staples.

Keywords: cesarean delivery; complication; infection; morbid obesity; obesity; postoperative.