Objective: To determine the efficacy of rocuronium to prevent fasciculations and biochemical changes after succinylcholine administration.
Patients and methods: Prospective, randomized double-blind trial enrolling 60 ASA I-II patients scheduled for elective surgery under general anesthesia. The patients were assigned to 2 groups to receive either 0.06 mg x Kg(-1) of rocuronium or physiological saline solution 90 seconds before administration of 1.5 mg x Kg(-1) of succinylcholine. The incidence and severity of fasciculations and serum concentrations of potassium before anesthesia and 3, 5, and 20 minutes after succinylcholine administration were recorded. Other serum concentrations recorded were myoglobin, creatinine phosphokinase and lactate before anesthesia and 20 minutes after succinylcholine administration.
Results: The increases in potassium levels at 3 and 5 minutes (0.3 +/- 0.3 and 0.2 +/- 0.4 mmol x L(-1)) and in myoglobin levels at 20 minutes (38.9 +/- 31.7 ng x mL(-1)) were attenuated by precurarization with rocuronium. The incidence of fasciculations was significantly lower (p<0.001) and their severity significantly less (p<0.001) in patients who received rocuronium before administration of succinylcholine.
Conclusions: Precurarization with rocuronium 90 seconds before succinylcholine administration reduces the incidence and severity of fasciculations and prevents increases in serum potassium and myoglobin concentrations.