Bradycardia associated with the use of vecuronium. A comparative study with pancuronium with and without glycopyrronium.

One hundred and twenty patients undergoing anaesthesia for elective surgery received either pancuronium or vecuronium for muscle relaxation. Within each of these two groups, half were given glycopyrronium and the remainder an inert placebo. The incidence of bradycardia or bradydysrhythmias was higher in the group having vecuronium compared with those given pancuronium. Glycopyrronium afforded protection against undesirable vagal activity.