Table 1. Hemodynamic and Electrocardiographic Changes before and after Test Dose

Data are mean ± SD.

* Measured immediately before induction of sevoflurane-anesthesia in the operating room.

† Measured 10 min after induction of sevoflurane-anesthesia and immediately before intravenous atropine.

‡ Measured 10 min after injection of atropine and immediately before intravenous test dose or saline (time 0 in fig. 1). At this time, hemodynamic variables and end-tidal concentrations of sevoflurane were stable.

§P < 0.05 for CLON-groups vs. CONT-groups.

∥P < 0.05 vs.  hemodynamics at ward.

#P < 0.05 vs.  TWA at preinduction.

CLON-EPI = children received clonidine premedication followed by intravenous test dose containing epinephrine; CLON-ISP = children received clonidine premedication followed by intravenous test dose containing isoproterenol; CLON-SAL = children received clonidine premedication followed by intravenous saline; CONT-EPI = children did not receive any premedication but received intravenous test dose containing epinephrine; CONT-ISP = children did not receive any premedication but received intravenous test dose containing isoproterenol; CONT-SAL = children did not receive any premedication but received intravenous saline; DBP = diastolic blood pressure; HR = heart rate; SBP = systolic blood pressure; TWA = T-wave amplitude; —= Data on hemodynamic responses to test dose in CONT-SAL and CLON-SAL groups were omitted because HR, SBP, and TWA were essentially unchanged in these groups.