Nondepolarizing muscle relaxant inhibits the sensitivity to acetylcholine on the muscle end -plate, and magnesium decreases the release of acetylcholine from the nerve terminal.
In randomized double-blind study of 80 hemodynamically stable patients, the effect of combined pretreatment with magnesium sulfate and pancuronium bromide on the degree of fasciculation and potassium release produced by succinylcholine chloride
were
evaluated.
Group I (n=20) received no pretreatment; Group II (n=20) received magnesium sulfate 20mg/kg; Group III (n=20) received pancuronium bromide 0.015mg/kg; Group IV(n=20) received magnesium sulfate 20mg/kg and pancuronium bromide 0.015mg/kg. All
patients
received succinylcholine chloride 1.0mg/kg thereafter.
Compared with control value in group I, serum potassium level was increased by the average of 0.07mEq/L at 5 minute 0.20mEq/L at 10 minute after administration of succinylcholine. The increase in serum potassium level administration of
succinylcholine
was attenuated in group II, III, IV, and the attenuation was more in group IV than group II, but less in group IV than in group III, But there were no statistically significant differences in the change of serum potassium level among 3 group. The
degree
of fasciculation was significantly reduced more in groups III and IV than in group I, and the reduction was more in group III than in group II, but more significantly in group III than in group I (p<0.0005).
It was speculated that the degree of fasciculation and the increase in serum potassium level were attenuated more in group IV than in group III, because of the combined action of magnesium sulfate and pancuronium on the neuromuscular junction
|