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Cold: "not dead until warm and dead"
A deeply hypothermic casualty can look dead and recover completely. Why you check breathing for a full minute, why the defibrillator still goes on, and why this region's winters make it a real scenario rather than a textbook one.
CPR in sixty seconds
- Unresponsive and not breathing normally? Gasping is not breathing. Treat it as a cardiac arrest.
- Call 112 (113 in Norway). Speaker on, phone on the floor. Stay on the line — the dispatcher will coach you.
- Push hard and fast in the centre of the chest: 5–6 cm in an adult, 100–120 per minute, letting the chest come all the way back up.
- Send somebody else for a defibrillator. Do not go yourself unless it is seconds away. Keep compressing.
- Turn the device on and do what it says. It decides whether to shock. After a shock, go straight back to compressions.
This is a reference written for bystanders, not a diagnosis, a training course or medical advice. It cannot tell you what is wrong with a particular person, and it does not replace the dispatcher on the other end of an emergency call — they can see what is near you and they will talk you through it. If you are worried about your own heart, or about a symptom, that is a conversation with a clinician rather than a page on a website.
Why the rule exists
Deep hypothermia slows the metabolism so far that a person can survive without a detectable pulse or breathing for far longer than in normal conditions, and full neurological recovery after prolonged hypothermic arrest is documented. The clinical shorthand — nobody is dead until they are warm and dead — is a real instruction to rescuers and to hospitals: resuscitation continues during transport and during rewarming, and in specialist centres a hypothermic arrest may be rewarmed on an extracorporeal circuit. In the Nordic and Baltic winter, and around cold water year-round, this is a scenario that actually occurs.
Take longer to decide
The signs of life in a severely cold casualty are faint. Breathing may be slow and shallow, the pulse slow and weak, the pupils fixed and the skin rigid. Guidance therefore allows a longer look — check for signs of life and normal breathing for up to a minute rather than ten seconds before concluding there is an arrest. If there is any doubt and there are no signs of life, start CPR; if there are signs of life, do not start compressions, because compressing a beating but very cold heart can tip it into fibrillation.
Handle them as if they were made of glass
A very cold heart is electrically unstable and rough handling — dragging, bending, jolting, sitting the person up — is a recognised trigger for ventricular fibrillation. Move a hypothermic casualty horizontally and gently, keep them flat, cut wet clothing off rather than pulling it, insulate underneath as well as on top, and cover the head. Do not rub the limbs, do not offer alcohol, and do not put them in a hot bath or against a heat source that warms the skin faster than the core.
The defibrillator still goes on
Attach the pads and do what the machine says. In severe hypothermia a shocked rhythm may not convert until the body has been rewarmed, and clinical practice limits the number of attempts before rewarming for that reason; that limit is a hospital decision, not a bystander one. Your job is unchanged: pads on, follow the prompts, keep compressing, do not stop because it did not work first time.
Avalanche, ice and immersion
Cold-water immersion, falling through ice and burial under snow all produce the same physiology by different routes and are all handled with the same caution. On ice, never walk out to somebody — lie flat, spread your weight and push something out to them, or call and wait for rescuers with equipment. In the water, cold shock in the first minute causes involuntary gasping and drives many drownings before hypothermia ever sets in, which is why the flotation-first rule matters more than swimming skill.
Sources: European Resuscitation Council Guidelines · Norwegian Air Ambulance Foundation (Stiftelsen Norsk Luftambulanse) · checked 2026-09-08
Frequently asked questions
How long do I check for breathing in a very cold person?
Up to a full minute, rather than the usual ten seconds. Cold makes breathing and pulse extremely difficult to detect, and starting compressions on a beating hypothermic heart carries its own risk.
Should I still use a defibrillator on a hypothermic person?
Yes. Attach the pads and follow the device. A very cold heart may not convert until it has been rewarmed, but that is decided in hospital; the bystander sequence does not change.
Can I warm them up with a hot drink or a hot shower?
No. Do not give alcohol, do not rub the limbs and do not apply direct heat to the skin. Insulate them, keep them flat and horizontal, handle them gently, and let the hospital rewarm the core.
What to do, right now
Is this a cardiac arrest?
Two checks decide it: not responding, and not breathing normally. The noisy gasping that fools nearly everyone, why a brief seizure at the start is a cardiac sign, and why a heart attack is a different emergency.
Hands-only CPR, in sixty seconds
Centre of the chest, 100 to 120 pushes a minute, 5 to 6 cm deep, let the chest come all the way back up, and do not stop. The rate, the depth, the fatigue problem, and a pacer that keeps you on the beat.
The emergency call, and the address problem
What the dispatcher asks, why the phone goes on speaker on the floor, how dispatcher-guided CPR works, and the single hardest question in a rural arrest: where exactly are you?
Using a defibrillator, step by step
Open it, turn it on, bare the chest, follow the voice. What the machine decides for you, what it will never do, and the one instruction people get wrong — go straight back to compressions after the shock.
Where the pads go, and what gets in the way
Right collarbone and left ribs, or front and back. Chest hair, sweat, snow, a medicine patch, a pacemaker lump, an underwired bra, a tattoo: which of these actually matter and what to do about each.
Everything on this subject
Before the emergency, there is a long quiet stretch
Blood pressure, resting heart rate, movement and sleep are the part of this you can act on for years beforehand. TempoLife keeps them in one place, free to start.