EFFECTS OF CALCIUM ON THE TIME COURSE AND POTENCY OF RELAXANTS / 解放军医学杂志

ABSTRACT

To evaluate the effects of calcium on the time course and potency of depolarizing and non depolarizing relaxants, 12 ASA grade Ⅰ Ⅱ patients were randomly divided into two groups. After anesthesia, succinycholine was administered intravenous in a dose of 1mg/kg in group S and vecuronium was administered in a dose of 0 05mg/kg in group V, respectively. 5% calcium chloride 20ml dissolved in 100ml saline were intravenously injected at the same time. The concentration of blood calcium and neuromuscular function (TOF) were monitored. The results showed (1) Both blood pressure and heart rate were increased in patients of two groups at 2 to 5min after calcium administration, and recovered to normal level 10min later. (2) The concentrations of blood total calcium and dissociated calcium were increased at 5min after calcium chloride administration and maintained to 10min. (3) The time of onset of effect of succinylcholine showed no changes, but the clinical action time and the recovery time were shortened after calcium administration. The recovery time of vecuronium was also obviously shortened by calcium chloride. It suggested that calcium can affect the time course and potency of both depolarizing and non depolarizing relaxants.