Accidental hypothermia.

Accidental hypothermia is an unintentional drop in core body temperature below 35 °C. It can occur at any time of year and in any climate, and can affect all age groups. The epidemiology of accidental hypothermia reflects the interaction between biological susceptibility, social conditions and exposure to environmental factors. As core temperature falls and thermoregulation mechanisms become insufficient, the metabolism slows, consciousness deteriorates and the hypothermic myocardium becomes increasingly prone to arrhythmias and cardiac arrest. The prognosis is variable, and treatment outcomes are dependent on multiple factors, with cardiac arrest being the decisive determinant, carrying an in-hospital mortality rate of up to 50%. Diagnosis relies on accurate core temperature measurement whenever possible, together with clinical staging when measurement is unavailable. The management of accidental hypothermia should follow the hypothermic chain of survival: prevent further cooling, handle the patient gently, provide airway, breathing and circulatory support, choose the correct destination hospital, and rewarm the patient using passive, active external, active internal or extracorporeal techniques according to severity. Extracorporeal life support is crucial for patients with hypothermic cardiac arrest. Most survivors of hypothermic cardiac arrest have excellent neurological outcomes. Effective prevention and education, together with well-organized regional pathways of care and personalized strategies to prevent cardiac arrest, are needed to improve outcomes.