Accidental hypothermia, defined as an unintentional decrease in core body temperature to below 35°C, adversely affects several body systems, including the cardiovascular, central nervous and renal systems. It is classified according to core body temperature from a maximum of 35°C in mild hypothermia to below 24°C in profound hypothermia. Patients with severe hypothermia (28°C-24°C) are at risk of cardiac arrythmias and cardiac arrest. In patients presenting with hypothermia, it is vital to prevent any further heat loss and quickly start rewarming them. Nurses working in the emergency department have a crucial role in supporting the optimal recovery of hypothermic patients. This article explains the pathophysiology of hypothermia, describes the investigations conducted in patients with accidental hypothermia and discusses management and nursing care.