Introduction

The majority of cold injuries can be prevented. The risk of cold injury can be reduced by:

Recognition of the type of cold climate and the hazards it presents;
A knowledge of how to use clothing and equipment to combat the cold; and
Early recognition of the initial stages of cold injury.

The information provided within this article is not intended to act as a replacement to professional advice but merely to provide the reader with an overview of common issues associated with physical activity and exercise.

Cold Climates

There are two types of cold climate, which are:

Cold Wet Climate; and
Cold Dry Climate.

In the cold wet climate there are alternative freezing and thawing conditions, as the air temperature rises and falls above 0. Sleet or rain causing waterlogged ground may be present and there is a risk of the following conditions occurring:

Hypothermia; and
Immersion foot.

In the cold dry climate, where the temperature is always below 0. A low air temperature combined with high winds and snowfall can cause the following injuries:

Hypothermia.
Frostbite.
Snow blindness.
Other possible injuries include:
- Frostnip (a mild form of frostbite).
- Chilblains.
- Windburn (chapped lips and skin).
- Sunburn (from the glare of reflected snow).
- Carbon Monoxide poisoning (from insufficiently ventilated stoves).

Hypothermia

The condition arising from an excessive loss of body heat is known as hypothermia. There is impairment of functions when the core temperature of the body drops and vital organs such as the brain, heart and liver start to cool. There are two types of hypothermia:

Immersion hypothermia or hypothermia of rapid onset.
Slow onset hypothermia also known as exposure.

Immersion Hypothermia

Immersion hypothermia, as its name suggests, is the result of rapid cooling by water.

Slow Onset Hypothermia

Hypothermia of slow onset occurs when the body is gradually cooled by the combined effect of low air temperature and high winds (known as wind-chill).

Other factors such as wet or inadequate clothing, poor nutrition and low morale increase the likelihood of this condition occurring.

Both hypothermia conditions are serious in nature. If unrecognised and untreated they can result in death.

In serious cases of hypothermia the casualty’s heart can stop beating. Regular checks on the pulse need to be carried out and care should be taken during evacuation to avoid jolting the casualty.

Recognition of Hypothermia

It is important that individuals are able to recognise the symptoms of hypothermia. As such, the casualty:

Feels cold and tired.
Have sudden and uncontrollable bouts of shivering.
Unexpected behaviour changes:
- Bursts of energy.
- Slurred speech.
Disturbance of vision.
Marked physical or mental lethargy.
Slowing down, stumbling and repeated falling.
Collapse, stupor, unconsciousness.

Treatment of Immersion Hypothermia

Slowly re-warm the casualty by:

Replace wet clothes with dry ones.
Place the casualty in a sheltered environment and re-warm by placing him/her into a sleeping bag.
Ensure that the head is adequately covered.
Give hot sweet drinks.
Do not give alcohol.
Evacuate as a stretcher case with head lower than the feet.

In serious cases of hypothermia the casualty’s heart can stop beating. Regular checks on the pulse need to be carried out and care should be taken during evacuation to avoid jolting the casualty.

Frostbite

Frostbite is a condition caused by freezing the body tissues. It is usually confined to the extremities and exposed parts of the body. When frostbite is extensive gangrene can occur with the subsequent loss of or amputation of affected parts.

The onset of frostbite is painless and so can easily go unnoticed. Pain can occur during and after the re-warming of frost-bitten areas. Frostbite can be recognised by:

The affected areas appear marble white.
The areas feel cold and firm.

Treatment of Frostbite

The treatment for frostbite is:

Warm the affected area with body heat.
Re-warm the entire body slowly.
Give hot drinks.
Evacuate.

Do not:

Rub the affected area.
Expose the area to fire or intense heat.
Exercise the effected part.

Immersion Foot

Immersion foot is a non-freezing injury caused by standing for long periods in cold wet conditions. It can be easily prevented if personnel at risk carrying out regular foot inspections and where necessary drying the feet, applying foot powder and changing into dry socks. If immersion foot is suspected look for:

The feet become white are numb with cold.
Swelling may occur.
On re-warming the feet become hot and painful.
Swelling increases, the colour of the affected area is mottled red and white with patches of blue.

Treatment of Immersion Foot

Immersion foot is treated by:

Remove the casualty to warm surroundings.
Remove the leg and foot covering.
Gently clean and dry the feet.
Elevate the feet to reduce swelling.
Warm the casualty but keep the feet exposed at room temperature.
Give hot sweet drinks.
Combat the pain with aspirin and treat as a stretcher case.

Do not:

Rub or massage the feet.
Damage any blisters.
Permit the patient to walk.
Do not expose to further cooling once treatment is in progress.

Snow Blindness

Snow blindness is a condition where damage to the eye has been caused by unprotected exposure to ultra-violet rays from the sun.

It is normally a temporary and reversible condition. It can occur where there is reflected glare from snowfields especially in high altitude. To recognise the condition look for: