Intravenous induction of therapeutic hypothermia in the management of junctional ectopic tachycardia: a pilot study.

Therapeutic hypothermia has been used to treat children with postcardiotomy junctional ectopic tachycardia (JET). However, cooling techniques have not been systematically studied. This pilot study investigates the safety and efficacy of intravenous cold saline infusions used to augment surface cooling to achieve a core temperature of 32-34 degrees C for pediatric patients with JET. For this study, 10 patients with JET were cooled using cooling blankets and 4 degrees C normal saline infusions to a target central temperature of 32-34 degrees C. Vital signs and central temperatures were monitored continuously during the cooling period. Comprehensive metabolic panels, complete blood counts, coagulation studies, and cultures were obtained per study protocol. Therapeutic hypothermia was achieved within 65 min (interquartile range [IQR], 45-75 min). The median heart rate decreased from 187 beats per min (bpm) (IQR, 184-190 bpm) to 158 bpm (IQR, 121-162 bpm). For all the patients, atrioventricular synchrony was restored either with conversion to normal sinus rhythm or with successful atrial pacing. No clinically significant electrolyte abnormalities or bleeding events occurred. Two deaths, not directly attributable to the cooling protocol, occurred. Intravenous induction of therapeutic hypothermia can be safely and effectively performed for children with JET. Further studies, powered for clinically relevant outcomes, should evaluate this potentially valuable therapeutic method.