Effect of H2-receptor antagonist pretreatment on vecuronium- and atracurium-induced neuromuscular block.

Abstract

Seventy-two patients were studied in a double-blind randomized controlled design to assess the effects of oral administration of cimetidine 400 mg, ranitidine 150 mg or placebo 90 min before anaesthesia on the neuromuscular blocking effects of atracurium 0.45 mg kg-1 or vecuronium 0.08 mg kg-1. The times to reappearance of T1 (first response in the train-of-four stimulation) and its recovery to 25% of control were 22.5 (SD) 5.2 and 30 (7.1) min, 30 (10) and 43 (15.4) min, and 25.8 (4.1) and 34 (6.2) min, respectively in the vecuronium groups pretreated with placebo, cimetidine and ranitidine, the times following cimetidine pretreatment being prolonged significantly (P less than 0.05). The respective recovery indices (times for 25-75% recovery of T1) in these three groups were 11.0 (3.5), 17.4 (6.8) and 13.0 (3.9) min. There were no significant differences in any of the variables following ranitidine pretreatment and either neuromuscular blocker or following cimetidine pretreatment and atracurium.