Accidental hypothermia

Accidental hypothermia is defined by the unintentional lowering of core body temperature to <95°F (<35°C).

Classified as mild, moderate, or severe according to core temperature. Some experts have suggested a further (more severe) category of profound hypothermia, at a core temperature <75.2°F (<24°C) according to some and <68°F (<20°C) according to others.

Core temperature measured in the lower third of the esophagus correlates well with pulmonary artery temperature and is preferred in patients with a secure airway.

Initial management should focus on stopping further cooling, resuscitation, and supportive care. This includes removing the patient from the cold environment, careful removal of wet or cold clothing, insulation, warming the body, securing the airway, monitoring breathing and circulation, and maintaining circulation using warm intravenous fluids.

Choice of rewarming strategy (passive external, active external, active interna/corel) is based on the patient’s core temperature and clinical features; a combination of techniques may be used.

Patients who have sustained a hypothermic cardiac arrest should ideally be rewarmed in a specialist center using extracorporeal life support.

Accidental hypothermia is characterized by the unintentional lowering of core body temperature to <95°F (<35°C).[1]Chivers K. Accidental hypothermia: pathophysiology, investigations and management. Emerg Nurse. 2022 Oct 25. http://www.ncbi.nlm.nih.gov/pubmed/36281752?tool=bestpractice.com

A threshold of 96.8°F (36°C) has been adopted in patients with trauma given that hypothermia is associated with higher mortality in this patient group.​[2]van Veelen MJ, Brodmann Maeder M. Hypothermia in trauma. Int J Environ Res Public Health. 2021 Aug 18;18(16):8719. https://www.mdpi.com/1660-4601/18/16/8719 http://www.ncbi.nlm.nih.gov/pubmed/34444466?tool=bestpractice.com ​​[3]Rösli D, Schnüriger B, Candinas D, et al. The impact of accidental hypothermia on mortality in trauma patients overall and patients with traumatic brain injury specifically: a systematic review and meta-analysis. World J Surg. 2020 Dec;44(12):4106-17. https://onlinelibrary.wiley.com/doi/10.1007/s00268-020-05750-5 http://www.ncbi.nlm.nih.gov/pubmed/32860141?tool=bestpractice.com

This topic covers accidental hypothermia in adults.