Wound infections involving infrainguinal autogenous vein grafts: a current evaluation of factors determining successful graft preservation.

PURPOSE: The purpose of this study was to review the natural history and clinical outcome of patients with infrainguinal autogenous graft infection (IAGI), to evaluate the effectiveness of attempted graft preservation, to determine those variables associated with graft salvage, and to better determine optimal treatment. STUDY DESIGN: We retrospectively reviewed the records of patients undergoing infrageniculate vein grafts at three hospitals between 1994 and 2000 who had a wound infection involving the graft. Clinical and bacteriologic variables were analyzed and correlated with graft salvage, limb salvage, and clinical outcome. RESULTS: During this 7-year period, 487 patients underwent an infrageniculate vein graft, and 68 (13%) had clinical evidence of IAGI. Twenty-seven patients presented with drainage from the wound, 15 with wound separation and cellulitis, 18 with soft tissue infection extending to the graft, 4 with an abscess and cellulitis, and 4 with bleeding. Ten patients (15%) had systemic symptoms (defined as a white blood cell count > 15,000 and temperature > 38.5 degrees C). Forty infections developed in the thigh, 17 in the groin, and 11 in the lower leg. An anastomosis was exposed in 15 patients. Wound cultures were positive for bacteria in 52 patients, and most infections were due to Staphylococcus aureus (18 patients) and S epidermidis (12 patients). Pseudomonas was cultured from seven infections. Twelve patients had polymicrobial infections. The interval from operation to infection ranged from 7 to 180 days. All patients were treated with oral antibiotics, 48 after intravenous antibiotics. Forty-five patients had operative debridement, including 18 who had muscle flap coverage. Four patients presented with hemorrhage, and three had immediate graft ligation and one graft excision. Follow-up ranged from 5 to 68 months (mean, 24.3 months), with 61 patients currently alive. Two patients died as a result of the IAGI (mortality rate, 2.9%). One had undergone a below-knee amputation, and one had a nonhealed wound but intact limb. Overall, 61 wounds (91%) healed, 4 patients required below-knee amputations, and 3 wounds did not heal. Fifty-eight grafts remained patent, 6 thrombosed, and 4 were ligated to control hemorrhage. Of the 61 wounds that healed, the time required for healing ranged from 7 to 63 days. No patient with bleeding died because of the acute episode. No patient had delayed hemorrhage. All 18 patients treated with a muscle flap healed. Bleeding (P <.001), elevated white blood cell count (P <.029), fever (P <.001), and renal insufficiency (creatinine level > 1.5; P <.056) were the only variables statistically significant in predicting graft failure or limb loss. With the use of life-table analysis, graft patency was 94%, 72%, and 72% at 1, 3, and 5 years, and limb salvage was 97%, 92%, and 92% at the same intervals, respectively. CONCLUSIONS: Most patients with an IAGI can be successfully treated with graft and limb preservation. In contrast to earlier studies, an exposed anastomosis, interval to infection, or Pseudomonas infection is not associated with graft failure. Graft salvage is less likely in patinets with fever, leukocytosis, and renal insufficency, but because most grafts remained patent, graft preservation is recommended for these patients. Graft ligation or excision should be reserved for patients presenting with bleeding or sepsis.