To Cool or Not to Cool During Cardiopulmonary Resuscitation

Therapeutic hypothermia following cardiac arrest improves neurologic outcome following adult ventricular fibrillation (VF) cardiac arrest and perinatal hypoxic ischemic encephalopathy. Evaluation of therapeutic hypothermia in the pediatric cardiac arrest population has been limited thus far to retrospective evaluations and to date there have been no published prospective efficacy trials. Two retrospective pediatric cohort studies showed no benefit from hypothermia compared to usual care. The timing (intra-arrest or post-arrest) and duration of hypothermia may impact patient outcome. While overshoot hypothermia <32°C, hypokalemia, and bradycardia are commonly associated with induced hypothermia, the risks of severe arrhythmia and bleeding are no worse than in normothermic controls. Despite this, rewarming has been identified as a vulnerable time for hypotension and seizure activity and may attribute to worse outcome. The American Heart Association's current recommendation is "therapeutic hypothermia (32-34°C) may be considered for children who remain comatose after resuscitation from cardiac arrest. It is reasonable for adolescents resuscitated from sudden, witnessed, out-of-hospital VF cardiac arrest." Ongoing research will help delineate whether induced hypothermia following pediatric cardiac arrest improves neurologic outcome.