Hypothermia & frostbite

Recognising hypothermia

Without a thermometer, the assessment is based on consciousness, not on shivering – shivering may be absent and is not a sign that the danger is over (ERC Guidelines 2025).

Experts assign the stages to core body temperature: mild 35–32 °C, moderate below 32–28 °C, severe below 28 °C (ERC Guidelines 2025). In an emergency it usually cannot be measured reliably – that is why consciousness is what counts.

1. Mild hypothermia: the person is awake and clear-headed, usually shivering
2. Moderate hypothermia: clouded consciousness – drowsy, confused, responds only when spoken to
3. Severe hypothermia: unconscious but breathing – life-threatening, call 144 immediately
4. No signs of life («apparent death»): not a death sentence – in deep hypothermia, pulse and breathing are often barely detectable, and even cardiac arrest is often still reversible

First aid for a person who is awake

1. Get them out of wind, wet and cold – improvise a windbreak, insulate from the ground
2. Replace wet clothing with dry, cover the head
3. Wrap in blankets or a survival blanket, warm up together
4. Only if the person is awake, clear-headed and able to swallow well: give warm, sugary drinks – NO alcohol
5. No hot bath and no hot shower
6. Active movement is only sensible with mild hypothermia

First aid for a drowsy or unconscious person

1. Call 144 immediately (in open terrain: Rega 1414)
2. Lay the person flat and move them as little and as slowly as possible
3. Protect from further cooling: insulation underneath, blankets, survival blanket
4. Unconscious with normal breathing: gently place them in the recovery position, moving the trunk and joints as little as possible, and do not reposition them afterwards; monitor breathing continuously
5. Check for signs of life for up to one minute, especially breathing (ERC Guidelines 2025)
6. No normal breathing: start resuscitation and continue until the emergency services take over – even if it takes a long time. Whether resuscitation continues is decided by the hospital after rewarming

Frostbite to fingers, toes, nose and ears

1. If the person is also hypothermic, that takes priority: first protect and warm the whole body
2. Do not rub numb, pale and hard areas, do not rub them with snow and do not expose them to direct heat (fire, heater)
3. Only thaw once the area will definitely stay warm afterwards – refreezing does more harm than staying frozen
4. Outdoors: warm hands or feet in the armpit or groin of a companion
5. If medical help cannot be reached quickly: thaw rapidly in a body-warm water bath – 37–39 °C, test with your elbow, never hot (International Commission for Alpine Rescue, ICAR; International Federation of Red Cross and Red Crescent Societies, IFRC)
6. Do not open blisters, cover the affected areas loosely and as sterilely as possible
7. Do not walk on a thawed foot any more – carry the person or arrange transport. If someone has to get themselves to safety, they are better off walking on the still-frozen foot and only thawing it once they reach their destination
8. Have every case of frostbite assessed by a doctor

Cold-water and ice-water shock (cold shock)

1. A sudden fall into cold water (below around 15 °C) triggers an involuntary deep breath – anyone submerged at that moment inhales water
2. This is followed by uncontrollably rapid breathing (hyperventilation) and a steep rise in pulse and blood pressure – this can leave you unable to act while swimming
3. The right response: do not panic, hold on to something or float and let the first breathlessness subside before swimming
4. After the rescue, protect immediately from further cooling and watch for the onset of hypothermia

Falling through ice – self-rescue and rescuing others

1. Self-rescue: stay calm, call loudly for help, turn towards the broken edge, hold on to the edge of the ice
2. Push or roll yourself flat onto the load-bearing ice, spread your weight over a large area and crawl flat on your stomach towards the shore
3. Rescuing others: secure yourself first – never approach the break in the ice upright, only lying flat
4. Reach out with an aid (branch, rope, ladder, scarf) to keep your distance from the break in the ice
5. Call emergency number 144 – after the rescue, hypothermia remains a threat

Prevention in the cold

1. Several layers of clothing («layering principle»), hat and gloves
2. Stay dry – wet clothing cools you down many times faster
3. Eat regularly and have warm drinks, the body needs fuel
4. During a power outage in winter: set up one room as a warm base and use it together

Further sources

• Rega Raising the alarm in open terrain 1414
• SAC Emergencies in the mountains
• Swiss Samaritans First aid for hypothermia
• ICAR: Mountain rescue medicine Treating frostbite on site (in English)