effect of midazolam premedication on hypnotic dose of propofol and recovery criteria in outpatient surgery

ABSTRACT

We investigated the effect of two small doses of midazolam on the hypnotic dose of propofol and recovery criteria in ambulatory gynecologic laparoscopic surgery. Sixty adult female patients, aging 18-40 years. ASA status I and II, scheduled for elective laparoscopic surgery were included. They were divided into three groups, in a random and double-blind fashion according to the drug given for premedication group "A" given 2 ml of normal saline, group "B" given 20 micro g/kg midazolam and group "C" given 40 micro g/kg midazolam. All drugs were given I.V. 15 minutes before induction of general anesthesia using standardized technique. Dose of propofol and the time needed to reach complete hypnosis were recorded. Recovery times from end of surgery till start of spontaneous respiration, extubation, spontaneous eye opening, obeying commands, ambulation and discharge from post-anesthesia care unit [PACU] and ambulatory surgical unit [ASU] were also recorded by blinded observer. We found that no significant difference was recorded between patients in groups "A" and "B" in all data [P < 0.05]. Group "C" patients showed significantly lower dose of propofol required for induction of general anesthesia and significantly shorter time required to reach complete hypnosis [P < 0.05]. Moreover, significantly longer time was needed to start spontaneous respiration, extubation and eye opening [P < 0.05], while no significant difference between the three groups in other recovery criteria. So, 40 micro g/kg midazolam given for premedication in outpatient surgery markedly decreases hypnotic dose of propofol required for induction of general anesthesia with minimal effect on recovery criteria and overall hospital discharge time