Caveats of Cooling: Available Evidence and Ongoing Investigations of Therapeutic Hypothermia

Abstract

Therapeutic hypothermia (TH) mitigates the long-term effects of neuronal excitotoxicity and cell death seen in hypoxic-ischemic encephalopathy (HIE). It remains the most evidence-based therapy for HIE, but it is not without clinical controversy. The literature abounds with questions, such as "When should we start cooling-as early as the delivery room?" "Given the efficacy of TH for moderate to severe HIE when started within 6 hours of birth, can we expand the therapy to infants with mild HIE?" "What should the target temperature be?" "What is the optimal duration of treatment?" "Is early discontinuation acceptable if the examination findings normalize?" These questions about TH, its incomplete neurologic rescue, and variations in the delivery of this therapy have prompted this review. This article summarizes changing procedural considerations for TH, the level of neuromonitoring available, the use of sedation, and considerations for neuroimaging during and after TH.