Guide · First aid

Frostbite

Frostbite is when skin and the tissue beneath it freeze, usually on the fingers, toes, nose, ears and cheeks. Anyone with frostbite needs medical care. If they are also confused, drowsy or shivering hard, treat hypothermia first — it is more dangerous — and call your local emergency number (112 in Europe and many other countries, 911 in North America).

Signs

• Frostnip (early): skin is cold, red or pale, and tingling or numb. It returns to normal on warming, with no lasting damage.
• Frostbite: skin turns white, grey or yellow, and feels hard, waxy or wooden. The area goes numb. After warming it may swell, blister, turn purple or, in deep frostbite, black.

Frostnip

1. Get out of the cold and wind.
2. Warm the area with body heat: put fingers in your armpits, or cover your nose and ears with warm, dry hands.
3. Don't rub it.

Frostbite

1. Move to shelter and protect the area from more cold.
2. Don't thaw it if it could freeze again. Refreezing causes much worse damage. If you must walk out on frozen feet, it is usually better to keep them frozen until you reach somewhere you can stay warm.
3. Remove rings, watches and tight clothing from the affected area.
4. Rewarm in warm water once you're somewhere safe. Use water that feels comfortably warm to an uninjured hand or elbow, about 37–39 °C. Too hot will burn numb skin that can't feel heat.
5. Keep it there for 15–30 minutes until the skin is soft and colour and feeling return. Top up with warm water as it cools. Rewarming is often very painful; a painkiller such as ibuprofen or paracetamol can help.
6. If you have no warm water, use body heat: armpits, the stomach, or a companion's skin.

After rewarming

• Pat the skin dry gently. Put dry, clean gauze between fingers and toes.
• Cover loosely with clean, dry dressings.
• Leave blisters intact.
• Keep the area raised if you can.
• Try not to walk on thawed feet.

Don't

• Rub or massage frostbitten skin, or rub it with snow
• Use direct heat such as a fire, stove, radiator or hot water bottle
• Drink alcohol or smoke, which reduce blood flow

Prevention

Keep dry, cover exposed skin, wear loose layers and mittens rather than gloves, and keep moving your fingers and toes. Check each other's faces for pale patches.

This guide does not replace a first-aid course. A few hours of hands-on practice will make you far more confident when it matters.

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