Effect of diazepam on pancuronium-induced neuromuscular blockade maintained by a feedback system

The possibility of an interaction between diazepam and pancuronium bromide was investigated in six patients undergoing general anaesthesia maintained with fentanyl, droperidol and nitrous oxide. Neuromuscular blockade was controlled using a feedback mechanism which automatically adjusted the rate of injection of pancuronium to maintain between 71.4 and 72.9% blockade. Diazepam 0.14 mg kg-1 i.v. produced blood concentrations within the therapeutic range, but did not produce consistent changes in the level of blockade, pancuronium concentration in the blood or pancuronium consumption measured over 20 min.