Haemodynamic effects of high-dose vecuronium compared with pancuronium in beta-blocked patients with coronary artery disease during fentanyl-diazepam-nitrous oxide anaesthesia

Background. Different combinations of neuromuscular blockers and opioids have been used in patients with angina pectoris to provide cardiovascular stability and reduce risk of myocardial ischaemia during anaesthesia.
Methods. We have compared the haemodynamic effects of high-dose vecuronium (0.3 mg kg^-1) with those of a standard dose of pancuronium (0.1 mg kg^-1) in patients scheduled for coronary artery bypass grafting during fentanyl-diazepam-nitrous oxide anaesthesia. All patients were receiving beta-adrenergic blocking agents. The given doses of vecuronium and pancuronium are equieffective with respect to duration of neuromuscular blockade.
Results. During a 25-min experimental period following the administration of the randomly selected drug, no significant changes in the haemodynamic parameters were observed in the vecuronium group. The administration of pancuronium, however, resulted in a significant mean increase in heart rate (20%), rate-pressure product (23%) and cardiac index (21%). Following endotracheal intubation in the pancuronium group, we observed an additional significant increase in mean arterial pressure and rate-pressure product.
Conclusion. High-dose administration of vecuronium has minimal haemodynamic effects and may thus offer a better alternative than pancuronium for long-lasting neuromuscular blockade in patients with coronary artery disease during fentanyl-diazepam-nitrous oxide anaesthesia.