Comparison of flunitrazepam and thiopentone for induction of general anaesthesia.

Forty female out-patients undergoing therapeutic abortion participated in a double-blind study comparing flunitrazepam 0.05 mg . kg-1 with thiopentone 6.0 mg . kg-1 as induction agents for general anaesthesia. Induction time, as measured by the time to loss of lid reflex and voluntary speech, was not only significantly longer in patients receiving flunitrazepam, but also much more variable and imprecise than with thiopentone. The Steward recovery room scores and psychomotor drawing test results revealed that recovery was significantly slower in the flunitrazepam group. Anterograde amnesia was observed in all patients who had received flunitrazepam and in one patient who had received thiopentone. No retrograde amnesia was found in either group. Flunitrazepam produced postoperative drowsiness, sedation, ataxia and nausea while with thiopentone discomfort from surgery and discomfort at the intravenous injection site were the main complaints. Because of the slowness of induction with flunitrazepam and marked individual variation, we do not feel that this drug can be considered a suitable agent for routine induction of general anaesthesia.