(WHS-O.06) Wound Alkalinity measurement to prognosticate the healing activities of DFUs
Thursday, May 16, 2024
6:00 PM – 6:30 PM East Coast USA Time
Purpose: The aim of this study was to determine whether and when wound alkalinity can be measured to prognosticate nonhealing DFUs and to predict healing outcome.
Methods: Wound alkalinity was monitored during the routine visits by assessing discarded wound dressings, via a disposable device - DETECĀ® pH, from 60 DFU patients to prognosticate healing outcome (probability of complete healing in 12 weeks).
Results: To determine the optimal time frame, the test sensitivity, specificity, pre- and post-test healing outcome of these patients were correlated with their wound alkalinity measurements from their 1st, 2nd and 3rd visits. Interestingly, we found that alkalinity assessment from the 2nd visit (7-21 days following the first visit) had the highest sensitivity (77.5%) and specificity (80.0%) to predict a non-healing outcome. The pre-test and post-test risk of a wound not healing was 88.9% and 96.9%, respectively, representing an 8.0% increased risk of not healing. The risk of non-alkaline wounds not healing was 69.2%, representing a 19.7% reduced risk of not healing. The improved predictability of the 2nd visit over the first visit can be explained by the wound healing processes. Specifically, following initial wound treatment, such as topical debridement, it takes at least 7 days for the wound to reach its homeostasis. Those patients with alkaline wounds during their 2nd visit suggest that the wounds did not initiate inflammatory responses after the standard of care and the wounds may have a higher chance of non-healing than those with non-alkaline wounds. Further analysis was carried out to determine the optimal time frame of the 2nd visit for prognostic healing outcome by dividing all DFUs patients (48 patients) based on their visit time frame following the first visit ( <7 days: 24 patients: 7-21 days: 24 patients). Our analyses show that, as compared to the <7 days group, the alkalinity determination for the 7-21 days group had highest sensitivity (87.5% vs 72.2%) and specificity (62.5% vs. 50.0%) to prognosticate the wound healing outcome. For 7-21 days group, while the pre-test and post-test risk of not healing was 66.7% and 82.4%, respectively, which represented a 15.7% increased risk of not healing. The risk of not healing when the wounds were non-alkaline was 28.6% which represents a 38.1% reduced risk of not healing. The results support that the 2nd visit (7-21 days after the initial diagnosis/ treatment) would be the best time for alkalinity determination with the best non-healing prognostic capability. Using a logistic regression model, we determined that, with all p-values>0.4, age, gender, race, initial wound size, wound location, and infection status were found to have negligible influence on predicted healing outcome based on wound alkalinity.
Conclusions: Our analyses show that alkalinity status can prognosticate healing outcome (p=0.0436).