Prediction of healing for postoperative diabetic foot wounds based on early wound area progression.

Abstract

To evaluate the probability of wound healing based on percentage of wound area reduction (PWAR) at 1 and 4 weeks in individuals with large, chronic, nonischemic diabetic foot wounds following partial foot amputation. Data from a 16-week randomized clinical trial (RCT) of 162 patients were analyzed to compare outcomes associated with negative-pressure wound therapy (NPWT) delivered through the V.A.C. Therapy System (Kinetic Concepts, San Antonio, TX) (n = 77) versus standard moist wound therapy (MWT) (n = 85). The 1- and 4-week regression models included 153 and 129 of the RCT patients, respectively. Early changes in PWAR were predictive of final healing at 16 weeks. Specifically, wounds that reached >or=15% PWAR at 1 week or >or=60% PWAR at 4 weeks had a 68 and 77% (respectively) probability of healing vs. a 31 and 30% probability if these wound area reductions were not achieved. Patients receiving NPWT were 2.5 times more likely to achieve both a 15% PWAR at 1 week and a 60% area reduction at 1 month (odds ratios 2.51 and 2.49, respectively) compared with those receiving MWT. Results of this study suggest that clinicians can calculate the PWAR of a wound as early as 1 week into treatment to predict the likelihood of healing at 16 weeks. This might also assist in identifying a rationale to reevaluate the wound and change wound therapies.