Succinylcholine, fasciculations and myoglobinaemia.

The prophylactic effectiveness of a small "self-taming" dose of succinylcholine (0.1 mg X kg-1), of d-tubocurarine (0.05 mg X kg-1), and of pancuronium (0.02 mg X kg-1) on succinylcholine-induced fasciculations and myoglobinaemia was studied in 64 healthy children (ages two to nine years), anaesthetized with halothane, nitrous oxide and oxygen. Serum myoglobin was analyzed by radioimmunoassay and taken as a tracer of muscle damage. No correlation was found between the serum levels of myoglobin and the incidence of muscle fasciculations. Self-taming with succinylcholine decreased the incidence of fasciculations (p = 0.001) but did not decrease the succinylcholine-induced myoglobinaemia (p = 0.224). D-tubocurarine (0.05 mg X kg-1) and pancuronium (0.02 mg X kg-1) both significantly reduced the myoglobinaemia and the fasciculations produced by succinylcholine. The pancuronium pretreated group presented less variable values of serum myoglobin which, when compared to the control group, had a more significant p value (p less than 0.001) than for d-tubocurarine pretreated group (p = 0.003). Muscle fasciculations and increased myoglobin levels were observed in children less than four years old who received succinylcholine. The prophylaxis of acute rhabdomyolytic renal failure due to succinylcholine (seven cases reported in the medical literature) is considered.