Cardiopulmonary resuscitation and hypothermia

Current basic life support (BLS) protocols do not address the physiologic effects of accidental hypothermia in prehospital care. The extreme levels of bradycardia, bradypnea, and peripheral vasoconstriction that often accompany profound hypothermia may complicate the accurate diagnosis of cardiopulmonary arrest in the unmonitored patient. Although CPR is indicated in the truly pulseless, apneic victim of hypothermia, chest compressions may convert nonpalpable but adequately perfusing sinus bradycardia to ventricular fibrillation. This dilemma had led to disagreement among clinicians and researchers in hypothermia about prehospital care protocols for the severely hypothermic patient. This article reviews the controversy and recommends the application of a normal BLS protocol to hypothermic patients presenting in apparent cardiopulmonary arrest.