A Comparative Study of Different Doses of Lignocaine on Prevention of Etomidate Induced Myoclonus during Induction of Anesthesia

Background and Aims Etomidate, an intravenous (IV) induction agent known for its stable myocardial action, can produce myoclonus which can be detrimental for the cardiac patients. Though lignocaine has proven its efficacy in attenuating the etomidate-induced myoclonus, the ideal dose of lignocaine is not known. The aim of our trial was to analyze two different doses of lignocaine on the occurrence and intensity of etomidate induced myoclonus. Materials and Methods A total of 120 patients were randomly assigned into three groups of 40 each. Patients in group A were injected lignocaine 0.5 mg/kg intravenously, group-B patients were injected lignocaine 1 mg/kg intravenously, and group-C patients were injected saline placebo. After 2 minutes, anesthesia was induced with 0.3 mg/kg of etomidate over 30 seconds. The patients were assessed for myoclonus using clinical severity scoring system during first 2 minutes of induction. Our primary outcome was the incidence of myoclonus. The severity of myoclonus and adverse effects were the secondary outcomes. Results No remarkable variation was found regarding demographic profile among three groups. Incidence of myoclonus in groups A and B was 35% and in group C was 98%, the difference being statistically significant. Both doses of lignocaine reduced the severity of myoclonus up to same extent. Conclusion Pretreatment with IV lignocaine 0.5mg/kg and 1 mg/kg IV remarkably decreased the occurrence and severity of myoclonus induced by etomidate up to same extent