Realistic expectations for pedal bypass grafts in patients with end-stage renal disease.

PURPOSE: Limb-threatening ischemia in patients with end-stage renal disease (ESRD) represents a challenging clinical problem. Multiple series have shown the inferior limb salvage rate for femoropopliteal or femorotibial bypass grafts in this group. This outcome study is restricted to those patients with ESRD who require pedal bypass grafts for attempted limb salvage. METHODS: Between December 1, 1990, and December 31, 1997, 34 patients with ESRD underwent pedal bypass grafting on 41 limbs. This review explores the patient and bypass graft outcomes and their relationships to typical risk factors. RESULTS: The average age in the study was 64 years (range, 39 to 85 years). Twenty patients (59%) were men, 31 (91%) had diabetes, 32 (94%) were hypertensive, and 28 (82%) had coronary artery disease, but only 10 patients (29%) were smokers. All the patients were undergoing dialysis except 2 patients with functioning renal transplants. All bypass grafting procedures were performed for limb salvage. The follow-up periods ranged from 1 to 84 months (average, 13.5 months). With life-table analysis, the cumulative assisted primary patency rate was 62% at 1 year and 62% at 2 years. The limb salvage rate was 56% and 50% at 1 and 2 years, respectively. All the patients who were seen with heel gangrene had early limb loss or died. Seven of the 16 amputations (44%) were performed despite patent bypass grafts. Ten of the 16 amputations (63%) occurred within 3 months of the surgery. The survival rate was 64% at 1 year and 52% at 2 years. After the bypass graft procedure, the mean ankle brachial index and the toe pressure rose from 0.48 to 1.05 and 18 to 86, respectively. CONCLUSION: Modest success can be expected with pedal bypass grafts in patients with ESRD, with most failures occurring in the first 3 months. Limb salvage rates lag behind graft patency rates because of progressive necrosis despite a hemodynamically functioning bypass graft. Heel gangrene is a strong predictor for a negative outcome. Lastly, overall patient survival rates are poor but comparable with the rates of other patients with ESRD.

Limb loss after lower extremity bypass.

BACKGROUND: Infrainguinal bypass now has a limb salvage rate approaching 90% at 10 years. This study helps elucidate the causes of limb loss despite bypass surgery. METHODS: A retrospective chart review of all patients undergoing a major lower extremity amputation after attempted bypass surgery. RESULTS: Between July 1987 and January 1997, 67 major amputations (52 below knee, 15 above knee) followed infrainguinal bypass for limb salvage in 64 patients. Of these patients, 53 (83%) were diabetic and 10 (16%) were on dialysis. The etiology of limb loss included thrombosed bypass (n = 33, 49%), lack of limb salvage despite patent bypass (n = 23, 34%), intraoperative bypass failure (n = 6, 9%), and exposed/infected bypass (n = 5, 8%). The 23 patients with patent grafts required amputations because of hindfoot necrosis (n = 6), persistent forefoot necrosis (n = 6), acute diabetic foot infection (n = 6), and various other reasons (n = 5). Using life-table analysis, survival for the whole group was 56% at 12 months and 17% at 48 months. Patients with limb loss despite a patent bypass fared the worst with survival of 21% at 2 years. CONCLUSIONS: Bypass thrombosis caused half of the amputations after limb salvage surgery. A patent bypass was functioning at the time of amputation in another third. Survival after failure of limb salvage was abysmal, especially in patients with patent bypasses.