Hypothermic Cardiac Arrest
Objective: Recognize that severe hypothermia changes the arrest: gentle handling, delayed meds/shocks as protocol writes, and transport toward rewarming.
Why This Is Hard
They were in the river and the monitor looks like asystole. Crews either work them like a warm VF or give up because the chest is stiff. AHA 2025 Part 10: hypothermia arrest is a special circumstance. Pulse checks are hard. Gentle handling. Rewarming is the therapy.
- Scene safety and get them out of the cold. Wet clothes off, insulation on.
- Feel for a pulse longer than usual (up to 60 seconds is common teaching) before starting CPR if there are possible signs of life — if none, start CPR.
- Destination is a center that can rewarm (ECMO/CPB in some systems). That is a protocol/destination question.
Field Rules (Education)
- AHA 2025: handle gently — rough movement can precipitate VF in severe hypothermia.
- Defibrillation and meds may be spaced or delayed below certain core temperatures in ACLS special-circumstances teaching. Follow your card. This site does not publish the temperature cutoffs as orders.
- Do not TOR on a profoundly cold patient with a recoverable story until rewarming is addressed per protocol.
- Drowning plus cold still needs ventilation. See drowning.
Field Pitfalls
- Declaring death because the chest is cold and stiff without a protocol TOR.
- Rough log-roll that throws them into VF.
- Giving a full warm-arrest drug cycle from memory.
Practice
60-second drill
Partner: ice fisherman, unresponsive, no obvious pulse, cold. First three actions including destination theme.
Related: Accidental hypothermia, Drowning.
Sources & Further Study
Named guidelines for further study. They are not clinical orders and do not replace your protocol or medical direction.
- NASEMSO National Model EMS Clinical Guidelines (2022) — U.S. EMS model language; protocol still wins
- AHA 2025 Part 10: Special Circumstances — hypothermia arrest: gentle handling, modified ALS, rewarming
Education only. Apply learning within your protocols and medical direction. This is not clinical care guidance.
Check Your Understanding
Street decisions from this lesson only. After you check, the key is highlighted. Education practice — not a certification exam.