Effect of halogenated anaesthetics on heart rate changes during reversal of neuromuscular block with glycopyrrolate and neostigmine.

The effect of halothane and enflurane on changes in heart rate during reversal of neuromuscular blockade was compared in 48 patients. Premedication and anaesthetic technique was standardized. Either halothane or enflurane was used as the primary anaesthetic. Neuromuscular block was reversed by injection of glycopyrrolate and neostigmine, given either separately or simultaneously. Heart rate changes were significantly different between the halothane and enflurane subgroups. Patients anaesthetized with enflurane showed less fluctuations in heart rate. Simultaneous injection of glycopyrrolate and neostigmine minimized the tachycardia in the halothane subgroups only.