Transcutaneous oxygen as a predictor of wound healing in amputations of the foot and ankle

Thirty-eight amputations of the foot and ankle were performed in patients with peripheral vascular insufficiency over a 20-month period. Amputation level selection was based on clinical examination, a minimum ankle-brachial index of 0.5 as a measure of vascular supply, serum albumin of 3.0 gm/dl as a measure of tissue nutrition, and a total lymphocyte count of 1500 as a measure of immunocompetence. Transcutaneous oxygen tension was measured at the midfoot and ankle levels prior to surgery. Thirty-two of 38 patients (84.2%) healed their amputation wounds. When the transcutaneous oxygen tension was greater than 30 mm Hg, 24 of 26 patients (92.3%) healed. When the value was below 30 mm Hg, only eight of 12 patients healed. When the propensity to support wound healing is factored out, with patients having the metabolic capacity to heal an amputation wound in the foot and ankle, it appears that transcutaneous oxygen tension is an accurate measure of vascular inflow to support amputation wound healing.