Hemodynamic factors as a cause of vascular surgery failures in diabetics

Thirty-six legs in thirty-three diabetic patients with ischemia at rest and multiple level arterial disease were studied preoperatively. Direct intraarterial femoral and popliteal artery blood pressures were measured together with indirect arm and foot blood pressures. Based on the systolic segmental pressure gradients it was predicted preoperatively whether it was necessary to make a one- or two-level reconstruction. The ankle pressure measured one month postoperatively correlated well with predicted values. Of the seventeen occlusions within the observation time hemodynamic factors played an important role in eleven cases. In the femoro-crural segment one occluded in which an iliac stenosis with a pressure gradient of 28% had been disregarded. In the femoro-popliteal above knee segment four occlusions occurred in cases where the postoperative ankle pressures were less than 80% of the preoperatively predicted value, suggesting stenosis at the anastomosis. A popliteal to ankle gradient of 39% was measured preoperatively in the fifth case which occluded 2 months postoperatively. In the aortofemoral segment five occlusions occurred all having femoral to ankle pressure gradients exceeding 40% of femoral artery pressure. Retrospectively, seven of the failures might have been prevented by two-level reconstructions and four failures by a secondary arterioplasty.