First aid; Effect of extreme cold

The body reacts to cold by shutting down blood vessles in the skin to stop "core heat" escaping. When deprived of warm blood, extremities such as finger or toes may freeze in severe conditions, causing frostbite. If the body's core temperature becomes dangerously low, bodily functions slow down (hypothermia) and may cease altogether.

Frosbite
This condition usually occurs in freezing and often dry and windy conditions. Those who cannot move are particularly vulnerable. The tissues of the extremities freeze-in severe cases this can lead to permanent loss of sensation and, eventually, gangrene.
Frostbite is often accompanied by hypothermia, which should be treated accordingly.
Recognition
There may be:
> At first, "pins and needles".
> A hardening and stiffening of the skin.
> A colour change to the skin of the affected area: first white; then mottled and blue; and eventually black;on recovery,red,hot,painful, and blistered.

Treatment
your aims are:
> To warm the affected area slowly, to prevent further tissue damage.
> To obtain medical aid if necessary.

1. Very gently remove gloves, rings, and any other constructions, such as boots. Warm the affected part with your hands, in your lap, or in the casualty's armpit. Avoid rubbing because it can damage skin and tissues.

2. Move the casualty into warmth before you thaw the affected part; carry her if possible when the feet are affected.
3. Place the affected part in warm water. Dry carefully, and apply a light dressing of fluffed-up, dry gauze bandage.
4. Raise and support the limb to reduce swelling. An adult casualty may take two paracetamol tablets for intense pain. Take or send her to hospital, if necesarry.