Hyperthermia and Hypothermia

Notes from a talk given by a doctor 11/1/95
Prevention

1.Don’t exercise in heat unless you are fit.
2.Don’t take part in fun runs in hot summer months.
3.Keep out of the sun if possible.
4.Wear Loose porous clothing NOT nylon or polyester.
5.Wear a wide brimmed hat.
6.Drink water frequently. In hot weather this amount may need to be increased when exercising.
7.Avoid alcohol, as this can cause dehydration.

There are three stages of heat illness:

1.Heat cramps.
2.Heat exhaustion.
3.Heat stroke.

1. Heat Cramps

These are recognised by the following symptoms:

• Muscle cramps of limbs and abdomen.
• Feeling tired, weak and dizzy.
• Feeling nauseated or vomiting.
• The skin feels cool and moist.

2. Heat Exhaustion

The symptoms of heat exhaustion are the same as for heat cramps, with the following additions:

• A headache which persists.
• Feeling giddy and faint.
• Shortness of breath.
• Sweating profusely and being very thirsty.
• Lack of co-ordination.
• Possibly confused or irritable.
The skin is pale, cool but clammy.

3. Heat Stroke

This is a potentially lethal condition, most common in athletes running long distances, or unfit people exercising in hot weather. The indications are:-

• Headache as before, with nausea or vomiting.
• Dizziness.
• Visual disturbance.
• Confusion, irritability and aggression.
• Possible seizures and coma.

An observer will notice the following signs in the sufferer:

• Feels very hot - a rise in temperature to 40deg. Celsius (normal body temperature is 37deg.).
• The skin is flushed and dry.
• Rapid pulse.


Treatment

1.Remove the person to a cool place.
2.Lie him/her down.
3.Loosen clothing. It may be necessary to remove some.
4.Give plenty of water. If the person is nauseated they should drink slowly.
5.Wet the body and clothes, and fan them if their skin feels hot.
6.If a towel is available, wet it and place to the neck, groins and arm pits, as this is where the large blood vessels are.
7.If ice packs are available, apply these to cramped muscles. DO NOT MASSAGE, but you can stretch the muscles.
8.Seek medical aid if the person is vomiting, unable to keep water down, or not recovering within a reasonable time (say, 20 to 30 minutes), and if you think they have heat stroke.


Hypothermia

Notes from a talk given by a doctor

7/6/95

Hypothermia can occur as a result of mild to moderate exposure to cold and is a dangerous condition, particularly in the case of prolonged immersion in cold water.

1.Prevention

• Wear warm inner clothing made from pure wool or thermals.
• Wear wind and water proof outer clothing.
• Eat adequate food before departure.
• Have a minimum of 4 persons in the party.
• Take adequate food and drink (not alcohol).
• If caught in bad weather take shelter early and watch for signs of cold exposure.
• Avoid more physical activity than necessary when conditions are extremely cold.
• Take adequate sleeping bags and covers if an overnight stay is planned.
• Check weather reports and ask locals about unusual weather conditions if walking in unfamiliar territory.

2.Symptoms

• A cold feeling and shivering.
• Excessive fatigue.
• Problems with vision.
• Faintness.
• Cramps.
• Increased slowness of mental and physical responses.
• Unco-ordinated movement, (e.g. stumbling).
• Slurred speach.
• Confusion.

When the condition is severe, the sufferer may:

• Feel cold to touch.
• Have a slow pulse.
• Have slow, shallow breathing.
• Be very quiet.
• Become unconscious.

3.Management

• Protect the person from wind, rain and cold/wet ground.
• If possible remove wet clothing and wrap the person in warm, dry clothing or a space blanket.
• If a sleeping bag is available, put the person in a warmed bag. Ideally, another person, stripped to underclothes, should share the bag.
• If conscious, give warm drinks but NOT alcohol.
• Adequately protect the nose and ears.

Under no conditions should you:

• Give alcohol.
• Warm the person in front of a fire.
• Use hot baths. (A warm bath 37deg, raised slowly to 40deg is OK).
• use hot water bottles.
• Use electric blankets.

Medial assistance should be sought if:

• recovery is not prompt.
• You suspect severe hypothermia.
• the person is unconscious.