Comparison of midazolam and diazepam to supplement total intravenous anaesthesia with ketamine for endoscopy.

Fifty patients undergoing endoscopy (laryngoscopy, bronchoscopy, mediastinoscopy) were anaesthetised in a double-blind prospective trial using total intravenous anaesthesia. Half of the patients were anaesthetised with an infusion of a solution of 250 mg ketamine and 12.5 mg midazolam. The other patients received an infusion of a solution of 250 mg ketamine and 20 mg diazepam. In addition, both groups were given increments of 50-100 μg of fentanyl. The immediate awakening time (t1) was not significantly different between groups, but the patients who had received midazolam-ketamine, had a significantly shorter time to more complete recovery (t2), a significantly lower frequency of emergence reactions and were more satisfied with the anaesthetic than the patients who had received diazepamketamine. There was no difference between groups with respect to intraoperative heart rate and blood pressure. No awareness during anaesthesia was reported.