Fluorometric prediction of successful amputation level in the ischemic limb

Abstract

The present study was undertaken to compare fluorometric documentation of fluorescein dye delivery with the standard means of determining the level at which an amputation should be performed in the dysvascular extremity. Thirty-nine patients underwent lower-extremity amputation at the level determined by the surgeon based upon physical examination, angiography, segmental pressure indices, and/or pulse volume recordings. In addition, fiberoptic fluorometry was performed preoperatively. After intravenous administration of sodium fluorescein (4-8 mg/kg), fluorometric readings were obtained by placing the fluorometer's light guide on 126 reading sites. Fluorometric findings were evaluated retrospectively, and therefore did not influence the surgeon's decision. Of the 39 amputations performed overall, only 26 healed. The accuracy of the standard criteria was lowest for the 20 below-ankle amputations, where only 12 cases healed. Alternatively, fluorometric indices separated healing from nonhealing sites in 36 of the 39 cases in 18 of the 20 below-ankle amputations. Overall, healing sites averaged 94 percent of the fluorescence of the healthy reference area, while nonhealing sites averaged only 29 percent. We conclude that fluorometry should prove to be a valuable adjunct in the assessment of the dysvascular extremity. It uses a low dose of dye, is easy to perform, and is readily repeatable.