Background:Bradycardia following administration of halothane and suxamethonium in children leads to reduced cardiac output, which can be prevented with prophylactic anticholinergics. Anticholinergics may result in tachycardia and arrhythmias. This study was designed to compare haemodynamic changes and incidence of cardiac arrhythmias following intravenous atropine and glycopyrrolate.

Study design: Ninety ASA I and II children between one month and twelve years were studied. Premedication was with oral promethazine 1mg/kg. Anaesthesia was achieved with 3% halothane in 33% oxygen and nitrous oxide. Patients were randomly allocated to receive atropine 0.01mg/kg (Group I) or glycopyrrolate 0.005mg/kg (Group II). Tracheal intubation was facilitated with suxamethonium 1.5mg/kg.

Results: Patients in Group I had a 35.7% rise in heart rate from baseline, compared to 22.5% in Group II two minutes after anticholinergic administration (p=0.001). Following intubation, heart rate rose by 9.7% and 13.2% (p