MARKED INCREASES IN HEART-RATE ASSOCIATED WITH SEVOFLURANE BUT NOT WITH HALOTHANE FOLLOWING SUXAMETHONIUM ADMINISTRATION IN CHILDREN

The changes in heart rate and arterial blood pressure following the ad ministration of suxamethonium in healthy children (mean age 3.8+/-0.3 years) during inhalational induction with either sevoflurane (n=22) or halothane (n=19) were studied. Heart rate 60 s following suxamethoniu m administration increased significantly in the sevoflurane but not in the halothane group. In the halothane group, four children required i ntravenous (i.v.) atropine as a result of bradycardia. None of the chi ldren in the sevoflurane group developed bradycardia following suxamet honium (P<0.05). Values of oxygenation, ventilation and age corrected minimal alveolar concentration were comparable at all measurement time s. The haemodynamic response to the administration of suxamethonium in children anaesthetized with sevoflurane seems to reflect the stimulat ion of the autonomic ganglia by suxamethonium whereas this positive ch ronotropic effect is attenuated or reversed by halothane.