Propofol-nitrous oxide versus thiopental-isoflurane-nitrous oxide for general anesthesia.

One hundred and twenty patients undergoing elective operations were randomly assigned to receive anesthesia with either thiopental, 4 mg/kg-isoflurane, 0.2-3%-nitrous oxide, 60-70% (control) or propofol, 2 mg/kg-propofol infusion, 1-20 mg/min-nitrous oxide, 60-70% (propofol). Although anesthetic conditions were similar during the operation, differences were noted in the recovery characteristics. For non-major (superficial) surgical procedures, the times to awakening, responsiveness, orientation, and ambulation were significantly shorter in the propofol group (4 +/- 3, 5 +/- 4, 6 +/- 4, and 104 +/- 36 min) than in the control group (8 +/- 7, 9 +/- 7, 11 +/- 9, and 142 +/- 61 min, respectively). In addition, less nausea and vomiting (20 vs. 45%) and significantly less psychomotor impairment was noted in the non-major propofol (vs. control) group. Following major abdominal operations, recovery characteristics did not differ between propofol and control groups. Delayed emergence (greater than 20 min), significant psychometric impairment, and a high overall incidence of postoperative side effects (55-60%) were noted in both drug treatment groups. The authors conclude that propofol-nitrous oxide compares favorably to thiopental-isoflurane-nitrous oxide for maintenance of anesthesia during short outpatient procedures. However, for major abdominal operations, propofol anesthesia does not appear to offer any clinically significant advantages over a standard inhalational anesthetic technique.