Hypothermia

Hypothermia is a medical condition in which the victim's core body temperature has dropped to significantly below normal and normal metabolism begins to be impaired. This begins to occur when the core temperature drops below 95 degrees fahrenheit (35 degrees Celsius). If body temperature falls further, down into the 80's (below 27 degrees Celsius), the condition can become critical and eventually fatal.

There are two types of hypothermia, acute and chronic. Acute hypothermia is the more dangerous; the body temperature goes down very swiftly, often in a matter of seconds or minutes when a victim falls through an ice-covered lake. Chronic hypothermia occurs when the body temperature goes down over a longer period of time.

Table of contents

1 Symptoms
2 Treatment

2.1 First Aid Treatment
2.2 Hospital treatment

3 Prevention
4 Medically Induced
5 See Also

Symptoms

shivering - but only in the early stages
dry, cold skin
slow pulse
slow breathing
drowsiness - sometimes mistaken for drunkeness - which can lapse into coma.

Never assume someone has died, as at low temperatures the body can survive very much longer than at normal temperatures.

Treatment

Treatment for hypothermia involves raising the core body temperature of the victim.

First Aid Treatment

The first aid response to someone experiencing hypothermia, however, must be made with caution.

Do not:

rub or massage the casualty
give alcohol
use hot water bottles or put the casualty in hot water
treat any frostbite

Any of these actions will divert blood from the critical internal organs and will worsen the situation.

Do:

call the emergency services
get the casualty to shelter
replace wet clothing with warm, if it can be done rapidly.
share body heat with the casualty by sharing a sleeping bag, survival bag, etc.
give food and hot drinks
monitor the casualty and be prepared to give Cardio-pulmonary resuscitation.

If the hypothermia has become severe, notably if the person is incoherent or unconscious, re-warming MUST be done under strictly controlled circumstances in a hospital. Bystanders should only remove the victim from the cold environment, including cold or wet clothing, and get the person to advanced medical care as quickly as possibly.

In hypothermia, the heart becomes extremely "irritable", and sudden re-warming can provoke cardiac arrhythmias, irregular beating of the heart in which blood isn't pumped adequately or may not be pumped at all. Common first aid wisdom in helping someone suspected of suffering from hypothermia is to treat them as if they as fragile as if made of glass - do nothing to over-stimulate the heart.

Hospital treatment

In a hospital, warming is accomplished gradually by internal administration of fluids under careful monitoring. If the victim starts to suffer irregular heartbeats, the equipment and personnel trained for providing the appropriate treatment are right at hand.

Prevention

Most heat is lost through the head, so hypothermia can be most effectively prevented by covering the head. Having appropriate clothing for the environment is another important prevention. Fluid-retaining materials like cotton, can be a hypothermia risk if the wearer gets sweaty on a cold day, then cools down and has sweat soaked clothing in the cold air. For outdoor exercise on a cold day, it is advisable to wear fabrics which can wick away sweat moisture. These include wool or synthetic fabrics designed specifically for rapid drying.

Medically Induced

Hypothermia is sometimes induced deliberately as preparation for surgery or to maintain artificial coma to increase survival chances after severe injury.