UMEM Educational Pearls

Title: Accidental Hypothermia

Posted: 11/3/2017 by Ashley Menne, MD (Updated: 11/22/2024)
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Core Temp <32 degrees leads to impaired shivering and confers increased risk for malignant ventricular dysrhythmias. Core Temp <28 degrees substantially increases risk of cardiac arrest.

If in cardiac arrest:

VA ECMO. Rewarming rate ~6 degrees per hour.
Cardio Pulmonary Bypass. Rewarming Rate ~9 degrees per hour.
Consider transfer to center with ECMO or CPB capabilities
Consider up to 3 defibrillation attempts for shockable rhythm
Consider with holding epi until core temp >30 degrees and doubling interval between doses (q6-10 minutes) until core temp >35 (European Resuscitation Council recs – note this differs from AHA guidelines/recommendations)

If perfusing rhythm:

Institute active external rewarming (warm environment, forced-air heating blankets, arctic sun, warm parenteral fluids). Rewarming Rate ~ 0.1-3.4 degrees per hour.
Consider minimally invasive rewarming with TTM cooling/rewarming catheter (Alsius/Zoll) via femoral vessel. Rewarming Rate ~3.5 degrees per hour.
Hemodialysis or CRRT can be considered if intravascular rewarming device unavailable. Rewarming rate 2-4 degrees per hour.
Avoid IJ or SC central lines, rewarming catheters, and HD catheters -- myocardial irritation with wire/catheter may precipitate ventricular dysrhythmia.

Consider addition of more invasive rewarming techniques in those with hemodynamic/cadiac instability or without access to VA ECMO/CPB:

Thoracic lavage. Rewarming rate ~ 3 degrees per hour
Peritoneal lavage. Rewarming rate ~ 1-3 degrees per hour

Consider stopping resuscitation efforts if/when:

K >12- suggests hypoxia before cooling, no reported survivors. Some recommend K of 10 as cutoff in adults.
Rewarmed to 32 degrees and no signs of life.

References

Douglas J. A. Brown, Hermann Brugger, Jeff Boyd, Peter Paal. (2012). Accidental Hypothermia. New England Journal of Medicine. https://doi.org/10.1056/NEJMra1114208