Remifentanil pretreatment reduces myoclonus after etomidate

Study ObjectiveThe aim of the study was to compare the effect of pretreatment with remifentanil 1 μg/kg and the effect of gender on the incidence of myoclonus after anesthesia induction with etomidate.DesignThis was a randomized, double-blind study.SettingThe study was conducted at a university hospital.PatientsSixty patients were pretreated in a randomized double-blinded fashion with remifentanil 1μg/kg or placebo. Two minutes after remifentanil or placebo injection, etomidate 0.3 mg/kg was given.MeasurementsMyoclonus was recorded with a scale of 0 to 3. The grade of sedation (none, mild, moderate, severe), nausea, pruritis, and apnea were recorded after injection of both drugs.Main ResultsThe incidence of myoclonus was significantly lower in the remifentanil group (6.7%) than in the placebo group (70%) (P < 0.001). None of the patients experienced sedation, apnea, nausea, or pruritis after injection of both drugs. In the placebo group, male patients were associated with significantly increased incidence of myoclonus after etomidate administration.ConclusionPretreatment with remifentanil 1 μg/kg reduced myoclonus after etomidate induction without side effects such as sedation, apnea, nausea, or pruritis. Men experience increased incidence of myoclonus than women after etomidate administration.