Functional Failure of Patent Femorodistal In Situ Grafts

We have treated several patients who required major, proximal extremity amputations despite a patent infrainguinal in situ saphenous vein bypass graft. To determine those factors predisposing to such paradoxical limb loss, we studied a group of 45 patients who underwent 48 in situ, femorodistal bypass grafts for tissue necrosis and who maintained a patent graft throughout the perioperative period. Within this cohort, we compared two distinct subgroups: Group I, whose limbs (n = 8) ultimately required a major proximal amputation; Group II, whose limbs (n = 40) emerged with a viable foot and did not require a major amputation. There was no significant difference in the incidence of diabetes, renal failure, smoking, or postoperative ankle/brachial index between the two groups. The presence of gangrene (88% vs 45%), invasive sepsis (63% vs 23%), and combined gangrene and sepsis (63% vs 18%) was significantly (p < 0.05) more prevalent in Group I versus Group II. Forty-three percent of patients with both gangrene and foot sepsis required a major proximal amputation despite a patent graft. Such patients are at high risk for limb loss even if they undergo successful revascularization.