Cardiac arrest with attempted cardiopulmonary resuscitation occurs in approximately 50 to 90 individuals per 100 000 annually, and 13% to 33% of these patients will have return of spontaneous circulation. Despite successful cardiac resuscitation, approximately 70% of patients do not regain immediate consciousness, with subsequent high mortality rates and poor neurological outcomes.1 Therapeutic hypothermia (TH) was introduced a decade ago as an intervention for comatose survivors of prehospital cardiac arrest. Initial clinical trials were based on experimental evidence suggesting that mild cerebral hypothermia (33°C-36°C) after return of spontaneous circulation improves both survival and neurological function. In 2005, the International Liaison Committee on Resuscitation and the American Heart Association published guidelines supporting the use of TH in comatose patients postcardiac arrest with return of spontaneous circulation. Consequently, TH, defined as 24 hours of cooling to 32°C to 34°C, is currently in use for this group of patients in many medical centers. Precise overall North American and European estimates on the use of TH are not available, and smaller survey estimates indicate that a wide range (11%-95%)2 of hospitals or intensive care units have a TH program, depending on survey methods and study period.
Little NE, Feldman EL. Therapeutic Hypothermia After Cardiac Arrest Without Return of ConsciousnessSkating on Thin Ice. JAMA Neurol. 2014;71(7):823-824. doi:10.1001/jamaneurol.2014.298