Electrophysiologic effects of lidocaine in children.

The effects of intravenous lidocaine on the refractory periods of the atrium, AV node and right ventricular myocardium were studied using His bundle recordings and the extrastimulus technique with and without atrial and ventricular pacing. The drug was administered in an intravenous bolus dose of 1 mg/Kg followed by an infusion of 100 micrograms/Kg/min. The AH, HV intervals and resting sinus cycle length as well as functional and effective refractory periods of atrium, AV node and right ventricle were measured before and 5 min afrer bolus injection of lidocaine. Neither of the refractory periods nor AH and HV intervals changed significantly following administration of lidocaine. The result of this first study in children is in agreement with previous reports of the effects of lidocaine on the cardiac conduction system in adults.