Study objective: To compare the pharmacodynamics of two commonly recommended doses of rocuronium bromide (0.7 mg/kg and 0.9 mg/kg) and succinylcholine (1.5 mg/kg) when used for rapid-sequence intubation.
Design: Prospective, double-blind, randomized study.
Setting: Operating rooms at a university hospital.
Patients: 45 ASA physical status I and II adult patients scheduled for elective surgeries under general anesthesia.
Interventions: Nonpremedicated patients were anesthetized with fentanyl 2 mcg/kg followed by thiopental sodium 4 to 5 mg/kg and muscle relaxant using rapid-sequence technique. Group 1 (n = 15) received rocuronium bromide 0.7 mg/kg. Group 2 (n = 16) received rocuronium bromide 0.9 mg/kg, and Group 3 (n = 14) received succinylcholine 1.5 mg/kg. Intubation was performed 60 seconds after the administration of muscle relaxant.
Measurements and main results: The case of intubation was scored using a scale of 1 to 4. Blood pressure and heart rate were measured beginning one minute before induction of anesthesia up to 5 minutes after intubation. Intubation scores were similar in groups 2 and 3 and were noted as good or excellent in all patients. Group 1 displayed a significantly lower intubation score than the other two groups; 60% were rated as poor. No significant differences in hemodynamic data were seen among the three groups.
Conclusions: Rocuronium bromide at a dose of 0.9 mg/kg provides intubating conditions similar to succinylcholine 1.5 mg/kg at 1 minute. Intubating conditions at 1 minute following a 0.7 mg/kg dose of rocuronium are not as good as those following a 0.9 mg/kg dose of rocuronium or a 1.5 mg/kg dose of succinylcholine.