Validation of the Ischaemia Severity Scale (ISS) Based on Non-Invasive Vascular Assessments (SEWSS) for Predicting Outcomes of Diabetic Foot Attack

Abstract

Assessment of ischaemia severity includes a variety of measures, such as pedal pulse palpation, the ankle/brachial index (ABI), and the toe/brachial index (TBI), but there is a lack of consensus regarding which ischaemia scale is the most effective for determining outcome prognosis. The purpose of this study is to validate the application of the ischaemia severity scale (ISS) in the effective prediction of wound healing, amputations, and mortality for diabetic foot wounds (DFW). This prospective study included 235 consecutive patients graded according to the Saint Elian Wound Score System (SEWSS). The ISS is part of this system, with patients being scored as non-ischaemic (0) or having mild (1), moderate (2), or severe (3) ischaemia. Age, diabetes duration in years, and ulcer size were found to be associated with a longer mean ischaemia of increasing severity. A trend of reduction in the pulse palpation rates (70.4%, 50%, 8.5% to 0%; p < 0.01), ABI (1.1 ± 0.1, 0.86 ± 0.3, 0.68 ± 0.2, 0.47 ± 0.2, p < 0.01), TBI average values (0.90 ± 0.35, 0.62 ± 0.52, 0.50 ± 0.33, 0.10 ± 0.42, p < 0.01), wound healing success (88.7%, 57.7%, 40.7%, 12.9%; p < 0.01), and delay in weeks (Kaplan–Meier: log-rank 44.2, p < 0.01) was observed with increasing values of the ISS (0, 1, 2, and 3). The odds ratio for adverse outcomes increased for each additional level of ischaemia severity. Thus, we demonstrate that the ISS is useful in effectively predicting adverse outcomes for DFW.