Wound blush as a predictor for limb salvage among people with non-healing diabetic foot ulcers

Background and objectives Wound blush represents angiographic visualisation of tissue-level perfusion around a diabetic foot ulcer. While wound blush after endovascular revascularisation (EVR) predicts improved outcomes, its’ prognostic value on diagnostic digital subtraction angiography (DSA) has not been studied, particularly in India. This study compared the role of wound blush after DSA and after EVR in predicting wound healing and limb salvage in non-healing diabetic foot ulcers. Methods A total of 428 individuals with diabetic foot ulcers underwent diagnostic DSA. Wound blush was assessed on DSA and, where applicable, after EVR. Participants were followed for wound healing and amputation outcomes. The wound blush positive and wound blush negative groups on DSA, among participants managed without EVR, and according to wound blush status following EVR were compared. Results On diagnostic DSA, 137(31.6%) participants were wound blush positive and 291(68.4%) were wound blush negative. Wound blush positive participants demonstrated higher rates of complete wound healing (90.5% vs . 79%; P =0.002), and lower amputation rates (7.6 vs. 22.2%; P <0.001) compared to wound blush negative participants. Among participants managed without EVR, limb salvage was significantly higher in wound blush positive than wound blush negative participants (92.4% vs. 77.8%; P =0.002). Following EVR, limb salvage was achieved in 89% of participants who demonstrated wound blush compared to 77% ( P =0.062) of those who remained wound blush negative. Baseline wound blush positivity predicted favourable outcomes irrespective of EVR. Interpretation and conclusions Wound blush on diagnostic angiography and after EVR is a strong predictor of wound healing and limb salvage in non-healing diabetic foot ulcers. Wound blush on initial DSA helps identifying participants in whom revascularisation may be deferred, reducing endovascular interventions without adverse limb outcomes.