Transcutaneous oxygen tension as a predictor of success after an amputation.

We measured local transcutaneous oxygen tension at the foot and proximal and distal to the knee in 162 patients who then had 206 amputations. When the values for oxygen tension at the foot and distal to the knee were compared with the success or failure of healing after an amputation of the foot or distal to the knee, respectively, a clearly increasing probability of failure was correlated with decreasing transcutaneous oxygen tension. However, even at a tension of zero the probability of failure was not 100 per cent. The results were similar for diabetic and non-diabetic patients. Preoperative values for transcutaneous oxygen tension were a much more consistent predictor of success or failure of healing after an amputation of the foot or distal to the knee than were measurements of systolic blood pressure at the ankle, but neither was predictive of the outcome after an above-the-knee amputation.