Lower extremity minor amputations: the roles of diabetes mellitus and timing of revascularization.

INTRODUCTION: Despite the frequent performance of minor foot amputations in patients with lower extremity vascular disease, little is known regarding the rate of conversion to major amputations and the role of bypass graft timing in relation to amputation. METHODS: Between January 1990 and December 2001, 670 patients underwent 920 minor amputations (interphalangeal, ray, or transmetatarsal) on 747 limbs. RESULTS: Of 670 patients, 468 were men (69.9%), 616 had diabetes mellitus (91.9%), and 137 (19.7%) had a serum creatinine level >2.0 mg/dL, of whom 92 were on dialysis (end-stage renal disease) (11.5%). Ipsilateral revascularization was performed < or =30 days before the initial amputation in 64.9% (485 of 747), whereas 9.8% (73 of 747) had a bypass < or =30 days postamputation. The initial amputation levels were 466 interphalangeal (62.4%), 159 transmetatarsal (21.3%), and 122 ray (16.3%). Operative 30-day mortality was 0.7% (6 of 920). Limb salvage was 89.8% at 1 year and 82.3% at 5 years. Diabetes mellitus had no impact on limb salvage (P = .61). Limb loss predictors included end-stage renal disease (odds ratio [OR], 1.72, 95% confidence interval [CI], 1.12 to 2.83, P < .01) and the need for transmetatarsal amputation as the initial procedure (OR, 1.62; 95% CI, 1.15 to 1.93; P < .01). Patients with revascularizations subsequent to an initial amputation had a significant increase in limb loss (OR, 2.11; 95% CI, 1.39 to 4.21, P < .005). Patient survival was 83.9% at 1 year and 43.5% at 5 years. Neither gender nor diabetes mellitus impacted survival; however, serum creatinine levels >2.0 mg/dL (5 years, 48.8% +/- 2.3% vs 23.9% +/- 4.2%, P < .0001) and the need for a major amputation < or =30 days (3 years, 60.8% +/- 2.1% vs 40.1% +/- 7.8%, P < .01) adversely affected survival. CONCLUSIONS: Although minor amputations can lead to limb preservation in most patients, the performance of a revascularization subsequent to amputation, transmetatarsal as the initial amputation, and end-stage renal disease are poor prognostic indicators. Inferior long-term patient survival is most closely associated with renal insufficiency and conversion to major amputation early after the initial procedure.

Major lower extremity amputation: outcome of a modern series.

HYPOTHESIS: Major lower extremity amputation results in significant morbidity and mortality. DESIGN: Retrospective database query and medical record review for January 1, 1990, to December 31, 2001. Mean follow-up was 33.6 months. SETTING: Academic tertiary care center. PATIENTS: Nine hundred fifty-nine consecutive major lower extremity amputations in 788 patients, including 704 below-knee amputations (BKAs) (73.4%) and 255 above-knee amputations (AKAs) (26.6%). MAIN OUTCOME MEASURES: Patient survival, cardiac morbidity, infectious complications, and subsequent operation. RESULTS: Overall 30-day mortality was 8.6%, worse for AKA (16.5%) than BKA (5.7%) patients (P<.001). Thirty-day mortality for guillotine amputation for sepsis control was 14.3% compared with 7.8% for closed amputation (P =.03). Complications included cardiac (10.2%), wound infection (5.5%), and pneumonia (4.5%). Twelve AKA (4.7%) and 129 BKA (18.4%) limbs required subsequent operation. Only 66 BKAs (9.4%) required conversion to AKA (average, 77.1 days postoperatively). Overall survival was 69.7% and 34.7% at 1 and 5 years, respectively. Survival was significantly worse for AKAs (50.6% and 22.5%) than BKAs (74.5% and 37.8%) (P<.001). Survival in patients with diabetes mellitus (DM) was 69.4% and 30.9% vs 70.8% and 51.0% in patients without DM at 1 and 5 years, respectively (P =.002). Survival in end-stage renal disease patients was 51.9% and 14.4% vs 75.4% and 42.2% in patients without renal failure at 1 and 5 years, respectively (P<.001). CONCLUSIONS: Major amputation continues to result in significant morbidity and mortality. Survivors with BKA require revision or conversion to AKA infrequently. Long-term survival is dismal for patients with DM and end-stage renal disease and those undergoing AKA.