Accidental hypothermia

Patients with associated underlying medical problems or with moderate or severe hypothermia (core temperature <32°C [<90°F]) require continued hospitalisation for careful monitoring.

If a patient has moderate or severe hypothermia, continuously monitor their core temperature and haemodynamic status during re-warming.[4]Dow J, Giesbrecht GG, Danzl DF, et al. Wilderness Medical Society clinical practice guidelines for the out-of-hospital evaluation and treatment of accidental hypothermia: 2019 update. Wilderness Environ Med. 2019 Dec;30(4 Suppl):S47-69. https://www.wemjournal.org/article/S1080-6032(19)30173-5/fulltext http://www.ncbi.nlm.nih.gov/pubmed/31740369?tool=bestpractice.com

• In practice, if the patient has mild hypothermia, monitor core temperature regularly, using rectal or tympanic measurements. In practice (unless the patient is in cardiac arrest and/or undergoing extracorporeal life support as this requires a tailored approach by a specialist), aim to re-warm the patient at a rate of 0.5℃ to 2℃ (0.9℉ to 3.6℉) per hour.

• Heat redistribution within the body can cause a continued fall in core temperature after removing the patient from a cold environment.

• Avoid hyperthermia during and after re-warming.[38]European Resuscitation Council. The European Resuscitation Council guidelines for resuscitation 2015. Oct 2015 [internet publication]. https://ercguidelines.elsevierresource.com  

• Patients with moderate or severe hypothermia require large volumes of fluids because vasodilation during re-warming causes expansion of the intravascular space. Infusing warmed intravenous fluid also offers an additional advantage of improved absorption of administered drugs.

In addition, monitor:

• Other vital signs:

  • Pulse rate

  • Blood pressure

  • Respiratory rate

  • Oxygen saturations

• Blood gases

  • Ensure resolution of hypoxia and normalisation of pH

• End-tidal CO₂ if the patient is intubated.

Patients with mild hypothermia (temperatures of 32°C to 35°C [90°F to 95°F]) who have been re-warmed and are in stable medical condition may be discharged from hospital, with no further follow-up required.