In this episode, Dr. Patrick Fink reviews accidental hypothermia for wilderness providers, building on Ep. 27 Thermoregulation, explaining physiologic changes as core temperature falls  and why accurate core temperatures are difficult to obtain in the field. 

We learn the modified Swiss staging system (0–4) based on signs and symptoms and outlines field management: 

- 0 cold stress (shelter, dry/insulate, warm calories; avoid alcohol), 

- 1 mild hypothermia (ataxia/fine motor impairment; passive plus active external rewarming with a hypothermia wrap and heat near axilla/groin; frequent reassessment), 

- 2 moderate hypothermia (confusion/lethargy; active external rewarming, evaluate hypoglycemia, gentle handling and no exertion to avoid afterdrop, cardiac monitoring, expedite evacuation), 

- 3 severe hypothermia (unresponsive with vital signs; airway/ventilation support, extremely gentle transport)

- 4 hypothermic cardiac arrest (60-second pulse check, CPR, limited shocks under 30°C, withhold epinephrine/amiodarone under 30°C, consider intermittent CPR per protocol, and note potassium’s role in termination decisions). 

We also briefly contrasts slow non-extracorporeal warming with ECMO/cardiopulmonary bypass, previewing a future episode on advanced care and the HOPE score

Links

Episode 27: Thermoregulation

WMS 2019 Accidental Hypothermia Guideline

AHA Hypothermia Guidelines

European Resuscitation Council Hypothermia Algorithm

Chapters:

00:00 Welcome and Overview
00:48 Hypothermia Basics
01:12 Cooling Physiology
04:06 Severe Effects and Arrhythmias
06:38 Field Temp Challenges
07:41 Swiss Staging Intro
08:35 Stage 0 Cold Stress
11:40 Stage 1 Mild Hypothermia
16:04 Stage 2 Moderate Hypothermia
20:44 Afterdrop and Handling
22:54 Stage 3 Severe Hypothermia
27:00 Stage 4 Cardiac Arrest
27:57 CPR Shocks and Drugs
37:01 Advanced Rewarming ECMO
43:26 Key Takeaways Summary
46:57 Wrap Up and Support

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