Prediction of below-knee amputation wound healing using noninvasive laser Doppler velocimetry

Abstract

Preoperative laser Doppler velocimetry (LDV) measurements of calf and brachial skin perfusion were performed in 29 patients prior to undergoing below-knee amputation; dual calf measurements on the anterior and posterior skin flaps were routinely obtained. Patients' ages ranged from 24 to 83 years; 16 had diabetes, 13 were smokers, 6 had hypertension, and 2 had known coronary artery disease. Anterior and posterior calf LDV values greater than or equal to 20 mV were associated with successful below-knee amputation wound healing in 25 of 26 patients; all 3 patients with either anterior or posterior calf LDV values less than 20 mV had below-knee amputations that failed to heal. Calculation of calf-brachial LDV indexes did not increase predictive accuracy compared to calf LDV measurements alone, although patients with wounds that failed to heal tended to have lower calf-brachial indexes. Preoperative noninvasive LDV may be used to aid in predicting the likelihood of successful healing after below-knee amputation.