Selection of amputation level in ischemia. Skin blood flow and perfusion pressure equally predictive.

In 33 patients who had major amputation for ischemia of the lower extremity, skin blood flow and perfusion pressure were compared in terms of prediction of amputation level. Skin blood pressure was measured photoelectrically. Only the blood flow was known to the surgeon. The primary amputation was performed below the level of the knee in 15 patients, through-knee in 14, and above the knee in only 4 patients. Primary healing was achieved in 27 patients, 5 patients had delayed healing at the same level, and 1 patient was reamputated. The same amputation level was predicted in 24 patients (primary healing/secondary healing/failure = 20/3/1) and a different one in 9 patients. In 4 patients the perfusion pressure suggested a more proximal amputation (2/2/0) and in 5 patients a more distal amputation (all primary healing). There was no difference between the two methods in predicting wound healing.