Hypothermia for Neuroprotection in Adults After Cardiopulmonary Resuscitation

With conventional cooling methods, patients in the hypothermia group were more likely to reach a best cerebral performance categories score of 1 or 2 (5-point scale: 1 = good cerebral performance, 5 = brain death) during hospital stay (individual patient data; relative risk [RR] = 1.55; 95% confidence interval [CI], 1.22 to 1.96) and were more likely to survive to hospital discharge (individual patient data; RR = 1.35; 95% CI, 1.10 to 1.65) compared with standard post-resuscitation care. Within six hours of cardiac arrest, lowering body temperature to about 91.4°F (33°C) and continuing to cool the body for 12 to 24 hours after cardiac arrest can inhibit glutamine and dopamine neurotransmitters, which otherwise lead to tissue damage.1 In theory, this should help preserve the blood-brain barrier, protect adenosine triphosphate stores, and decrease intracranial pressure, ultimately reducing cell death in various brain regions.2 The five studies included in this Cochrane review each used different cooling methods.1 Three of the five studies utilized conventional cooling methods, such as ice packs, cooling pads, water immersion, and cold fluids. According to guidelines from the International Liaison Committee on Resuscitation, therapeutic hypothermia should be tried in unconscious adult patients with spontaneous circulation if they had an out-of-hospital cardiac arrest from ventricular fibrillation.5 It can also be considered in patients with any cardiac arrest.5 Address correspondence to Hossein Hassani, MD, at hhassani@schsa.org.