Pretreatment with sufentanil reduces myoclonus after etomidate.

BACKGROUND: Myoclonic movements are a common problem during the induction of general anesthesia with etomidate. We investigated the influence of pretreatment with the opioid sufentanil on the incidence of etomidate-induced myoclonus. METHODS: Forty female patients (ASA physical status I-III) were randomly assigned to receive double-blinded either 0.3 micro g kg-1 of sufentanil or placebo 150 s before the induction of sleep with 0.3 mg kg-1 of etomidate. The patients were observed for any myoclonic movement. Grade of dizziness, breathing frequency, non-invasive blood pressure and heart rate were measured during the study period. RESULTS: None of the 20 patients receiving sufentanil had myoclonic movements after the administration of etomidate, whereas 16 patients in the placebo group (80%) experienced such movements (P<0.01). No cases of apnoea before induction of sleep were seen in the sufentanil group. CONCLUSION: Sufentanil 0.3 micro g kg-1 is an effective and safe drug to reduce myoclonus after etomidate without causing any harmful side-effect.

Midazolam pretreatment reduces etomidate-induced myoclonic movements.

During induction of anaesthesia with etomidate, myoclonic muscle movements are frequent. In this study, pretreatment with a small dosage of etomidate or midazolam was compared with placebo for the prevention of myoclonic muscle movements. Sixty patients, premedicated with oral midazolam, were pretreated in a randomized double-blinded fashion with etomidate 0.05 mg/kg i.v., midazolam 0.015 mg/kg i.v. or normal saline i.v. (placebo) in three groups of 20 patients each. The pretreatment was followed after 90 seconds by etomidate 0.3 mg/kg i.v. One minute after onset of hypnosis, induction of anaesthesia was completed with sufentanil and rocuronium. From the time of pretreatment to completion of anaesthesia, patients were observed for myoclonic muscle movements by a single physician, blinded to group allocation. Myoclonic movements were graded on a scale of 0 to 3. The incidence of myoclonic movements was significantly lower in patients pretreated with midazolam (4 of 20) compared with placebo (18/20) (P < 0.01). Midazolam 0.015 mg/kg i.v., administered 90 seconds before induction of anaesthesia with etomidate, is effective in reducing etomidate-induced myoclonic muscle movements.