Salvage of Infected Vascular Grafts with Antibiotic Impregnated Beads

OBJECTIVES: To determine if antibiotic impregnated polymethylmethacrylate beads utilized in conjunction with serial debridement and local muscle flaps can enhance the salvage of infected vascular grafts.
METHODS: A retrospective review of 20 vascular graft infections treated in 19 patients over a 3 year period. The treatment protocol included serial debridement, placement of antibiotic beads (one 40 gram package polymethylmethacrylate + 4 grams powdered vancomycin + 2.4 grams powdered tobramycin) and culture specific intravenous antibiotics. Repeat debridement and bead exchange was performed every 3 to 5 days until a clean, culture negative wound was achieved. Formal closure was achieved with a local muscle flap followed by six weeks of intravenous antibiotics.
RESULTS: Twenty graft infections were treated in 19 patients with a mean age of 59 years of which 16 were acute and 4 sub-acute. Seventy percent of the grafts were alloplastic (Gortex, PTFE) and 30% autologous vein. The most commonly identified organisms were Enteroccus, Methycilin Sensitive Staphylococcus Aureus, Enterobacter Cloaccae and Methycilin Resistant Staphylococcus Aureus. On average 2.65 (±0.58) bead exchanges were performed over a mean treatment period of 9.05 (±5.24) days. After obtaining a clean, culture negative wound definitive coverage was provided with a local muscle flap. Successful graft salvaged was achieved in 95 % of patients and no patients (0%) required amputation. One recurrent infection (5%) was encountered requiring graft removal.
CONCLUSIONS: Polymethylmethacrylate antibiotic (PMMA) impregnated beads can provide a useful adjunct in the treatment of infected vascular bypass grafts. The 95% graft salvage and 0% limb loss rates compare favorably to historic controls (graft salvage 66%, amputation 12%).