THE INFLUENCE OF ANESTHETIC METHOD ON INFRAINGUINAL BYPASS GRAFT PATENCY - A CLOSER LOOK

Although several studies have demonstrated a reduced incidence of post operative deep venous thrombosis among patients who receive regional a nesthesia, the influence of anesthetic method on early arterial bypass graft patency has not been well studied. The records of 78 consecutiv e patients undergoing elective femoro-popliteal (FP) or femoro-tibial (FT) bypass grafts, and who were randomized to receive general anesthe sia and postoperative patient-controlled intravenous narcotic analgesi a (GEN, n = 41), or epidural anesthesia and postoperative continuous e pidural analgesia (EPI, n = 37), were retrospectively reviewed. The tw o groups were evenly matched with respect to demographic characteristi cs, risk factors, and vascular variables. There was one death in each group, yielding an operative mortality of 2.6 per cent, and leaving 76 patients available for further analysis. Graft occlusion occurred in 11 (14.5%) cases within the first 7 postoperative days, including 9 (2 2.5%) GEN and 2 (5.6%) EPI patients (P < 0.05). There were two (4.4%) FP occlusions, including two (8.7%) GEN and 0 (0%) EPI cases; there we re nine FT occlusions, including seven (41.2%) GEN and two (14.3%) EPI cases. Graft occlusion occurred in 11 (17.1%) of the 64 limb salvage cases, including nine (27.3%) GEN and two (6.5%) EPI cases (P < 0.05), and in seven (12.7%) of 55 greater saphenous vein grafts, including s ix (22.2%) GEN and 1 (3.6%) EPI cases (P < 0.05). By multivariate anal ysis, FT grafts, preoperative plasminogen activator inhibitor-1 (PAI-1 ) levels, and GEN were predictive of early graft occlusion (P < 0.05), Furthermore, the levels of circulating PAI-1 were higher 24 hours pos toperatively among patients in the GEN group (P < 0.05). Epidural anes thesia and postoperative analgesia appear to convey a higher rate of e arly infrainguinal bypass graft patency.