Long QT syndrome unmasked by dexmedetomidine: a case report.

Dexmedetomidine is a selective alpha-2 adrenergic agonist that is used frequently for short-term sedation in children. It has been noted to cause hypertension, hypotension, bradycardia, and sinus pauses; however, QTc prolongation has not been reported with dexmedetomidine administration. We describe a case of marked QT prolongation with use of dexmedetomidine in a pediatric critical care setting. Clinicians should be vigilant about potential QT prolongation in patients on dexmedetomidine, particularly in those receiving multiple other medications.