A randomized double blind comparative study on onset time and intubating conditions achieved with succinylcholine 1.5mg/kg and Rocuronium 0.6mg/kg & 0.9mg/kg IV

Introduction: A perfect setting for tracheal intubation include a rapid onset, and short duration of action. These requirements are best met by succinylcholine, an ultrashort acting depolarizing muscle relaxant. However its many unwanted side effects have necessitated a search for an alternative drug. Rocuronium bromide is a steroid, non-depolarizing neuromuscular blocking agent with a rapid onset and an intermediate duration of action. It may be a suitable alternative to succinylcholine. Aim of Study: To study and compare the efficacy of rocuronium bromide in two dosage schedules – 0.6mg / kg (2 x ED95) and 0.9mg / kg (3 x ED95) IV, with succinylcholine chloride 1.5mg / kg IV in patients with respect to: 1. Intubating conditions at one minute 2. Onset of action 3. Adverse effects Materials and Method: This study was conducted at Government Stanley Hospital, Chennai, in the patients undergoing general surgical procedures. After institutional approval and informed consent, 60 patients were enrolled in the study. Group A: Succinylcholine 1.5 mg/kg (Sch 1.5) Group B: Rocuronium bromide 0.6 mg/kg (2 x ED 95)(Roc 0.6) Group C: Rocuronium bromide 0.9 mg/kg (3 x ED 95)(Roc 0.9) Anaesthesia was induced with Thiopentone sodium 5mg/kg over a period of 20 seconds. The ulnar nerve was stimulated at the wrist using 0.1 Hz single twitch stimulation mode and the supramaximal current was determined. Once a control twitch height was established the bolus of randomly assigned neuromuscular blocking agent was administered intravenously in less than 5 seconds. When injection was completed, a timer was started and after 20 seconds the ulnar nerve was stimulated using single twitch mode at a frequency of 1 Hz. At one minute, intubation was performed and scored by a blinded experienced anaesthesiologist. anaesthesia was maintained with Nitrous oxide, oxygen and Neuromuscular blocking agents. Results and Observations: Vocal cord relaxation is comparable between group a and c. Excellent intubating conditions was seen with Group A (Sch 1.5mg/kg) with 100% score. Excellent intubating conditions with Group B (Roc 0.6 mg/kg) and Group C are 30% and 85% respectively. P value of Succinylcholine 1.5 mg/kg and Rocuronium 0.9 mg/kg is 0.466 statistically not significant. Conclusion: Succinylcholine is an ideal agent for intubation in all surgical procedures. Intubating conditions of Rocuronium bromide at a dose of 0.9mg/kg (3xED95) is comparable to Succinylcholine 1.5mg/kg at 1minute.Rocuronium bromide 0.9 mg/kg can be used safely in patients where Succinylcholine is contraindicated.