Calcium gluconate pretreatment for prevention of succinylcholine-induced myalgia.

The effects of calcium gluconate pretreatment on succinylcholine-induced postoperative muscle pain and on the changes in serum potassium and calcium levels were studied in 80 patients undergoing elective surgery who were to become ambulatory on the same evening. A test group of 40 patients was given 10 ml of 10% calcium gluconate intravenously immediately before induction of anesthesia with thiopental followed by succinylcholine for tracheal intubation. A control group of 40 patients was given thiopental and succinylcholine without calcium gluconate. Muscle pains were graded according to severity as nil, mild, moderate, and severe. The incidence of postoperative muscle pains was significantly less (5%) in the test group than in the control group (45%). In control patients who subsequently developed muscle pain, serum levels of potassium were significantly increased above preinduction levels 2 min after succinylcholine was administered and serum calcium levels were significantly decreased. In control patients who did not develop postoperative myalgia, there were no significant changes in serum levels of either calcium or potassium. This was also true for patients pretreated with calcium gluconate. Therefore, calcium gluconate pretreatment reduces both the increase in serum potassium and the decrease in serum calcium associated with succinylcholine, and decreases the incidence and severity of postoperative myalgia.