Abstract
We evaluated the effects of the addition of nitrous oxide (N2O) to propofol/epidural anesthesia on the dose requirements of anesthetics, emergence times from anesthesia, and incidence of postoperative emesis. Fifty patients scheduled for lower abdominal surgery were allocated into one of two groups; patients were ventilated with 1l•min-1 of oxygen and either 2l•min-1 of air (control group, n=25) or N2O (N2O group, n=25). Epidural anesthesia was performed using lidocaine. Propofol was infused to maintain a bispectral index of between 40 and 60. The mean required amount of intravenous infusion of propofol was significantly lower in the N2O group (4.6±1.1mg•kg-1•h-1) than in the control group (6.7±2.3mg•kg-1•h-1). However, the cost of anesthetics was significantly higher in the N2O group than that in the control group. There were no significant differences in the total amount of other anesthetics, emergence times, and the incidence of postoperative emesis between the two groups. We conclude that there is no clinical advantage in using N2O during propofol/epidural anesthesia.
