The influence of anesthetic method on infrainguinal bypass graft patency: a closer look

Although several studies have demonstrated a reduced incidence of postoperative deep venous thrombosis among patients who receive regional anesthesia, the influence of anesthetic method on early arterial bypass graft patency has not been well studied. The records of 78 consecutive patients undergoing elective femoro-popliteal (FP) or femoro-tibial (FT) bypass grafts, and who were randomized to receive general anesthesia and postoperative patient-controlled intravenous narcotic analgesia (GEN, n = 41), or epidural anesthesia and postoperative continuous epidural analgesia (EPI, n = 37), were retrospectively reviewed. The two groups were evenly matched with respect to demographic characteristics, 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 (22.5%) 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 were 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 six (22.2%) GEN and 1 (3.6%) EPI cases (P < 0.05). By multivariate analysis, 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 postoperatively among patients in the GEN group (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)