An exaggerated hypertensive response to glycopyrrolate therapy for bradycardia associated with high-dose dexmedetomidine.

At our institution, high-dose i.v. dexmedetomidine is used to provide sedation for pediatric patients undergoing nonpainful radiological imaging studies. Some of these patients exhibit marked bradycardia (more than 20% deviation from the lowest age-adjusted normal values) while maintaining an arterial blood pressure within an acceptable normal range. We report on three cases wherein treatment of dexmedetomidine-induced bradycardia with i.v. glycopyrrolate (5.0 microg/kg) not only resulting in resolution of bradycardia but also resulting in an exaggerated increase of arterial blood pressure.