Predicting success in limb salvage

While success in revascularization procedures for severe arterial insufficiency--limb salvage--demands a technically correct operation, the adequacy of the outflow system is equally important. An outflow index (phi), the percentage drop in femoral artery pressure following an intra-arterial injection of papaverine, was developed. The predictive value of this index was demonstrated in a prospective study of 44 limbs in which an aortoiliac procedure with profundoplasty was done for multilevel disease. In the operations considered completely successful (n = 27), the mean value of phi was 37 +/- 8 per cent; this was significantly greater (P less than 0.001) than the mean value of 16 +/- 9 per cent found for those operations (n = 17) deemed to have been unsuccessful on the basis of rigorous postoperative criteria. This finding not only proves the efficacy of the index, but emphasizes the importance of an outflow system with the ability to accept more blood.