Comparison of Intubating Conditions of Rocuronium Bromide and Vecuronium Bromide with Succinylcholine Using “Timing Principle”

BACKGROUND: Rapid and safe endotracheal intubation is of paramount importance in general anaesthesia. The aim of this study was to compare the intubating conditions of succinylcholine with rocuronium bromide and vecuronium bromide using “Timing principle”. The timing principle entails administration of a single bolus dose of nondepolarizing muscle relaxant, followed by an induction drug at the onset of clinical weakness. PATIENTS & METHODS: 75 patients were divided into three groups of 25 each. Patients allocated to Groups A and B received rocuronium 0.6 mg kg(-1) and vecuronium 0.12 mg kg(-1) respectively. At the onset of clinical weakness (ptosis), anesthesia was induced with propofol 2.5 mg kg(-1); intubation was accomplished after 60 seconds of induction agent in both groups. Patients in Group C received propofol 2.5mg kg(-1) followed by succinylcholine 2mg kg(-1) and their tracheas were intubated at 60s.Train of four count was assessed at adductor pollicis muscle using nerve stimulator at intubation and time to loss of TOF was observed. in group A and B. Intubating conditions were assessed according to a grading scale and haemodynamic variables were compared at 1,3 and 5 minutes after intubation. RESULTS: Intubating conditions were either excellent(84% in group A,48% in group B and 88% in group C) or good (16% in group A, 48% in group B and 12 %in group C)and only 4% pt had poor intubating conditions in group B. Patients were interviewed postoperatively, and all were satisfied with the technique of induction of anesthesia.Rocuronium and Vecuronium are haemodynamically stable drugs as compared to Succinylcholine. CONCLUSION: Rocuronium 0.6 mg kg(-1) provides good to excellent intubating conditions at 60 s comparable to succinylcholine after the induction of anesthesia using the timing principle.