Effect of Epidural Levobupivacaine on Recovery from Vecuronium-Induced Neuromuscular Block in Patients Undergoing Lower Abdominal Surgery

Abstract

The aim of this study was to evaluate the effect of epidural levobupivacaine on recovery from vecuronium-induced neuromuscular block. Ninety patients undergoing lower abdominal surgery were randomised into two groups after an epidural test dose: the epidural group (n = 45) received a bolus of 15 ml of 0.5% levobupivacaine whereas the control group (n = 45) did not. Anaesthesia was induced and maintained with propofol, fentanyl, vecuronium and nitrous oxide. Neuromuscular block was induced with vecuronium 0.1 mg/kg and monitored with acceleromyographic train-of-four at the adductor pollicis. Patients in each group received neostigmine at 25% recovery of the first twitch of train-of-four during recovery from anaesthesia. The effect of epidural levobupivacaine on the speed of recovery of neuromuscular function was evaluated. The lag time, onset time and time from vecuronium administration until 25% T1 recovery did not differ between the groups. The times of the recovery index (the time from 25% to 75% recovery of T1) and of the DUR 25-train-of-four 90 (time from 25% T1 to train-of-four ratio of 0.9) in the epidural group were significantly longer than those for the control group (5.2 [2.1] vs 3.04 [1.02] minutes and 10.8 [3.3] vs 8.2 [2.3] minutes, P < 0.001). This study shows that epidural levobupivacaine significantly delays the train-of-four recovery from vecuronium-induced block. Although the interaction is small in the clinical setting, anaesthetists should take this interaction into consideration when combining general and epidural anaesthesia during surgery.