The Effect of Oral Clonidine Premedication and Adequate Dose of Intravenous Glycopyrrolate for Correction of Bradycardia in Children

Park, Dong Ho; Park, Jung Won

Abstract

BACKGROUND: Clonidine is one of the effective premedicant but may cause biadycardia and hypotension. This study was designed to investigate the efficacy of two doses of oral clonidine as a premedicant and to evaluate the interaction between clonidine and intravenous glycopyrrolate, according to dose.
METHODS
Sixty children(3-8 years old) were randomly selected and assigned to one of thtee groups: control(no premedication, n=20), clonidine 2(2 ug/kg, n=20), clonidine 4(4 ug/kg, n=20). Patients received clonidine orally 90 min before the estimated time of arrival at the operating room. Vital signs and percutaneous oxygen saturation were evaluated before premedication, 60 min, 90 min after premedication and then sedation score was evaluated on arrival at the operating room. After record the baseline heart rate, all patients received glycopyrrolate 4 ug/kg intravenously and changes of heart rate were evaluated. Incremental doses of glycopyrrolate (2 ug/kg every 3 min) were administered until heart rate increase by 20 beats/min.
RESULTS
The sedation score was significantly higher in the clonidine 4 group(Ridit score=4.8, p=0.03). In the clonidine 4 group, the heart rate was decreased significantly compared to other groups. In each group, there were no differences in blood pressure, respiratory rate, percutaneous oxygen saturation. Doses required to increase heart rate by 20 beats/min were 5.8+/-1.2 ug/kg in the control group, 7.2+/-1.6 ug/kg in the Clonidine 2 group, 8.1+/-1.8 ug/kg in the clonidine 4 group and there were no significant differences between 3 groups.
CONCLUSIONS
Oral clonidine 4 ug/kg produced satisfactory sedation and decreased heart rate but no patient required to treatment for bradycardia. Oral clonindine premedication did not blunt the response of heart rate to intravenous glycopyrrolate.