Journal: Anesth Analg 105(5):1298-1302, 2007. 19 References
Reprint: Klinik für Anästhesiologie und Intensivtherapie, Klinikum der Friedrich-Schiller-Universität Jena, Erlanger Allee 101, 07740 Jena, Germany (L Hüter, MD)
Faculty Disclosure: Abstracted by S. Ouellette, who has nothing to disclose.
Etomidate, because of its minimal respiratory side effects and favorable hemodynamic profile, is a common choice for short procedures. This is especially true in the hemodynamically compromised patient. Two undesirable side effects of etomidate are pain on injection and myoclonus. Pain on injection has been resolved by a new lipid formulation for etomidate. Myoclonus is still seen in up to 90% of patients during induction of anesthesia with etomidate if no supplemental opioids are used.
A number of drugs have been investigated for suppression of etomidate-induced myoclonus, but the drug of choice for short procedures has yet to be identified. Opioids suppress myoclonus but may also cause apnea. A pretreatment drug should prevent myoclonus, be short-acting, and not have significant effects on respiration and hemodynamics. A drug to prevent myoclonus should also not prolong recovery. This study was designed as a placebo-controlled study to investigate the effects of pretreatment with low-dose IV midazolam on the incidence and severity of myoclonus during anesthetic induction with etomidate for elective cardioversion in unpremedicated patients.
Forty ASA PS 3-4 patients scheduled for cardioversion were randomly assigned to receive either 0.015 mg/kg midazolam or 0.9% saline as placebo 90 seconds before the injection of 0.3 mg/kg etomidate. Myoclonic movements and sedation were recorded on a scale between 0 and 3. Pulse oximetry, noninvasive arterial blood pressure, and heart rate were recorded during the study period. Two patients (10%) in the midazolam group had myoclonic movements after administration of etomidate and 10-20 patients (50%) receiving placebo experienced such movements. No other differences were found between the groups and there was no difference in recovery 5 minutes after the administration of etomidate. |
