The “gold standard” for amputation level selection: Xenon-133 clearance

Abstract

Numerous noninvasive testing modalities for prospective lower-extremity amputation level selection have been reported and include Doppler ultrasound pressure measurements, thermography, calf muscle pH, radioisotope skin perfusion pressures, and pulse volume recording. Although each of these techniques has improved the accuracy of amputation level selection, compared to indirect perimeters such as assessment of skin bleeding at surgery, none of these test modalities provides a clear-cut objective endpoint. This report describes our experience with determination of skin blood flow by xenon-133 clearance techniques for prospective amputation level selection. Between July 1, 1977, and April 1, 1980, 137 lower-extremity amputations were performed in 102 patients. Preoperative xenon skin blood flow determinations were available in 76 lower-extremity amputations. Amputation levels included 6 toe, 9 transmetatarsal, 13 Symes, 36 belowknee, 7 knee disarticulation, 4 above-knee, and 1 hip disarticulation. In amputations with flow rates exceeding 2.2 ml/100 g tissue/min 70 74 (95%) healed primarily. Four healing failures were due to errors in surgical judgement (two) and late stump trauma (two). Our data suggest that xenon-133 clearance techniques provide accurate objective information for amputation level selection at all levels of lower-extremity amputation. In addition, utilization of this type of objective amputation level selection technique provides a remarkably high incidence of conservative amputations including toe, transmetatarsal, Symes, and knee disarticulation.