Modified frailty index is predictive of wound complications in obese patients undergoing gynecologic surgery via a midline vertical incision

Abstract Objectives There are limited methods to identify which obese patients will experience wound complications after undergoing gynecologic surgery. We sought to determine the association between frailty and postoperative wound complications and to develop a prediction model for wound complications in this patient population. Methods We reviewed prospectively collected data of obese patients undergoing laparotomy though midline vertical incisions from 7/2013-3/2016. Modified frailty index (mFI) was calculated using 11 comorbidities previously validated. The primary outcome was the composite rate of postoperative wound complication. Data was analyzed using Fisher exact test or Chi-square and t-tests or Kruskal-Wallis tests. Poisson regression models were used to generate relative risks. Prediction models were created with receiver-operator characteristic curve analysis. Results Of 163 patients included, 56 (34%) were considered frail. Wound complications occurred in 52 patients (31.9%): 28 (50%) frail and 24 (22.4%) non-frail patients (RR 2.23, 95%CI 1.29-3.85). Frail patients had significantly greater frequencies of wound breakdown (37.5% vs 15%, RR 2.51, 95%CI 1.31-4.81). After controlling for BMI, tobacco use, and maximum postoperative glucose, frailty remained an independent predictor of wound complication (aRR 1.88, 95%CI 1.04-3.40). The area under the curve for the predictive model incorporating frailty was 0.73 for wound complications. Conclusion Frailty is associated with wound complications in obese patients undergoing gynecologic surgery via a midline vertical incision and is a useful tool in identifying the most high risk patients. Further prospective research is necessary to incorporate mFI into preoperative planning and counseling.