PREVENTION OF HISTAMINE-INDUCED CARDIOVASCULAR REACTIONS DURING THE INDUCTION OF ANESTHESIA FOLLOWING PREMEDICATION WITH H1- + H2-ANTAGONISTS I. M.

In a prospective controlled double-blind study, 60 elective surgical patients were randomly assigned to three premedication groups. Twenty patients received promethazine 0. 5 mg kg −1 i.m. 45 min before induction of anaesthesia; a further 20 patients received an additional i. m. injection of cimetidine 400 mg 120 min before induction. The third group (n = 20) served as the control group. Following vecuronium 0.02 mg kg −1 , anaesthesia was induced with fentanyl, and etomidate. All patients then received suxamethonium 1.5 mg kg −1 i. v. The combined administration of H 1 - + H 2 -antagonists as premedication led to a significant reduction in the increase in heart rate when compared with the effects in the other groups.