A Study of Ankle – Brachial Index as a Prognostic Indicator in Diabetic Foot Ulcers

Abstract

Background and objectives. ABSTRACT Foot ulcerations are a common complication of diabetes accounting to 15% of all diabetics. 15% of diabetics undergo lower limb amputation. Ankle-Brachial index has a sensitivity of 70.6% & specificity of 88.5% in diagnosis of peripheral vascular diseases. But no literature is available where ABI is studied as a prognostic indicator in diabetic foot ulcers. Can ABI predict the outcome of diabetic foot ulcers ? The objective of this study was to assess ABI as a prognostic indicator in diabetic foot ulcers. Methodology. The present study was conducted in the Department of Surgery K.L.E.S Dr. Prabhakar Kore Hospital and Medical Research Centre , Belgaum on 74 patients with diabetic foot ulcers between Nov 2008 to Nov 2009. The ABI was measured by Colour Doppler on the day of admission. The patients were treated as per hospital protocols. They were followed up for 6 months. The outcome of the ulcers were categorized into 2 groups: limb salvaged & major amputation. Retrospectively the ABI were reviewed & analysis was done. Results. There were 66 males & 8 females in the study. 64.9% of patients were in the age group of 71 –90 years. 43.2 % of patients had diabetes since 6 – 9 years. Infection was present in 59.5% & absent in 40.5%. Neuropathy was present in 56.8% of patients & absent in 43.2%. ABI for patients who underwent major X amputation was < 0.84 ( 0.74 +/- 0.1) . ABI for patients in whom limb salvage was possible was 0.84 – 1.0 ( 0.92 +/- 0.08) . Conclusion. ABI is falsely raised in diabetics due to atherosclerotic calcification of vessels. ABI is an excellent prognostic indicator in diabetic foot ulcers. If ABI is < 0. 84, one should consider angiography & revascularization procedure. If angiography shows diffuse disease unsuitable for revascularization or if the angiography is not affordable to the patient then, surgeon should consider major amputation without wasting time. ABI between 0.84 – 1.0 is more in favour of healing of the ulcer & salvage of limb. However larger trials are required for better assessment of ABI as a prognostic indicator in diabetic foot ulcers.