A Study to Assess the Effect of Pretreatment with Rocuronium Bromide in Reduction of Etomidate Induced Myoclonus during Anesthetic Induction
Introduction: Induction agents are drugs that, when given intravenously in an appropriate dose, cause rapid loss of consciousness. They are also used to maintain anesthesia by intravenous infusion, as the sole drug for short procedures done under local anesthesia and to provide conscious sedation in intensive care unit.
Materials and Methods: This study is a prospective, randomized, double blind study conducted in hospitas attached to Bangalore medical college & Research Institute, Bangalore. A written informed consent was obtained from all patients included in the study. As per protocol, clearance was taken from institutional ethical clearance. The incidence of myoclonus in the non pretreatment group was estimated to be 80% based on previous studies. To detect a 50% difference in the incidence of myoclonus at a confidence interval of 95% and keeping a power of 80%, a minimum of 35 patients in each group was required.
Results: In the Rocuronium group, 40% had Myoclonus and in Saline group, 75% had Myoclonus. There was significant difference in Myoclonus incidence between two groups. Odds ratio was 4.5. I.e. Incidence of Myoclonus was 4.5 times higher in Saline group than in Rocuronium group. For Grade 1 Myoclonus, odds ratio was 1.92. There was no significant difference in Grade 1 Myoclonus between two groups. For Grade 2 Myoclonus, odds ratio was 3.733. I.e. Grade 2 Myoclonus was 3.733 times higher in Saline group compared to Rocuronium group. There was significant difference in Grade 2 Myoclonus between two groups. For Grade 3 Myoclonus, odds ratio was 14.4. I.e. Grade 3 Myoclonus was 14.4 times higher in Saline group compared to Rocuronium group. There was significant difference in Grade 3 Myoclonus between two groups.
Conclusion: Pretreatment with priming dose (0.06mg/kg) of rocuronium bromide modifies the induction of anaesthesia with etomidate by reducing the incidence of myoclonic movements and preserves the advantages of etomidate: cardiovascular stability, minimal respiratory depression and cerebro-protective effects.
Keywords - Induction agents, Rocuronium, Myoclonus, Etomidate.