Sedative and hypnotic properties of propofol during epidural or spinal anesthesia

: The sedative and hypnotic properties of propofol were studied in 40 patients undergoing elective gynecologic or orthopedic surgery using epidural (epidural group, n = 20) or spinal (spinal group, n = 20) anesthesia. Patients were given a bolus dose of 1 mg.kg-1 immediately followed by a continuous infusion of 4 mg.kg-1.h-1 of propofol after epidural or spinal anesthesia. The patients were asked to open their eyes on command at 10-sec interval from the end of the bolus infusion of propofol. We administered oxygen when SpO2 decreased below 93%. The mean induction time to reach the level of sedation, no response to verbal command to open their eyes, was 6 +/- 10 (SD) min in the epidural group, and 7 +/- 17 min in the spinal group. The mean recovery times, judged by ability to open eyes and recall date of birth, were 4 +/- 4 min and 7 +/- 6 min in the epidural group, and 4 +/- 4 min and 5 +/- 5 min in the spinal group, respectively. There were no differences in all recorded times between the two groups. Oxygen inhalation was needed in 75% of the patients in the epidural group and 100% in the spinal group. These results indicate that bolus and continuous infusion of propofol produces rapid induction, deep level of sedation, and rapid recovery during epidural or spinal anesthesia. However, respiratory depression appeared at this infusion rate during regional anesthesia.