A dose-response relationship for etomidate, with some observations on cumulation.

In a within-patient comparison in 30 subjects, sleep was induced before e.c.t. by different doses of etomidate or methohexitone: etomidate 0.1 mg/kg, 0.2 mg/kg, 0.4 mg/kg or methohexitone 1.5 mg/kg. The duration of hypnotic effect was assessed by recording the time of spontaneous waking and later, of recovery of normal ocular muscle tone. Doubling the dose of etomidate produced a significant increase in both sleeping time and late recovery. Compared with methohexitone 1.5 mg/kg, etomidate 0.2 mg/kg provides an equal duration of sleep, but allows faster late recovery. In eight patients in whome sleep was maintained by repeated injections of etomidate 0.1 mg/kg as required, little evidence of cumulation was seen up to 27.5 min duration of sleep.