European Journal of Molecular & Clinical Medicine

Abstract

Etomidate is a popular intravenous induction agent because it has a stable haemodynamic profile and
results in minimal histamine release. Myoclonus is observed in 50%–80% of patients who did not
receive pretreatment before etomidate administration, which increases the risk of regurgitation and
aspiration in emergency conditions. Various drugs were used in the treatment of myoclonus but the
results have been inconclusive. Dexmedetomidine, a new alpha-2 agonist has been tried by several
authors to suppress the myoclonus induced by etomidate. A prospective randomized controlled double
blind study was conducted in seventy patients aged between 18-55 years belonging to ASA I and II
scheduled for elective surgery under general anaesthesia. After obtaining informed written consent, a
detailed preanaesthetic evaluation was done and investigations were obtained as indicated. The patients
were randomized into 2 groups with 35 patients each, received either 0.5 μg/kg of dexmedetomidine in
10 ml saline (Group D) or 10 ml of Saline (Group S) over a period of 10 minutes prior to etomidate
induction. The incidence of severe myoclonus was significantly less in group D compared to saline
group with p = 0.031 (8.57% in group D and 28.5% in group S). However there was no change in the
incidence of myoclonus (P = 0.237) and pain on injection (p = 0.309) in both groups. Recovery profile
was comparable in both groups. Our study shows that pretreatment with dexmedetomidine 0.5 μg/kg
IV is effective in reducing the severity of etomidate induced myoclonic muscle movements without
however dexmedetomidine does not have any significant effect on the incidence of myoclonus
following etomidate induction.