Hypothermia, or low body temperature, results from prolonged unprotected exposure to a cold environment. Immersion in cold water causes much greater loss of body heat, and exposure to air the same temperature and thus can cause hypothermia within minutes (Wearing wet clothes in a cold environment also increases heat loss and the likelihood of hypothermia.) Small children and infants are especially prone to hypothermia. Our physiological functions, metabolism, and central nervous system can function within a very narrow temperature range. As the body loses heat, several internal senses attempt to maintain the internal or core temperature as close to 98.6°F (37°C) accessible. Blood flow is diverted to the upper body to preserve heat within the brain, heart, lungs, and other vital organs. The hands, feet, arms, and legs become cold first, but are designed to tolerate this decrease in temperature fairly well. Shivering (rapid involuntary contractions of muscles) generates heat to preserve core body temperature.
- Numbness and/or weakness
- Loss of coordination
- Inappropriate behavior
Move victim to a warm area. If this is not possible, shelter her from the wind, change any wet clothing, and put her in a sleeping bag if one is available. An adult lying in the same sleeping bag may provide additional heat for a child. Give the victim something warm to drink, if she is able to drink and it is available.
If symptoms persist, if there is any loss of consciousness, or if there has been an immersion in near-freezing water, take the victim to the nearest emergency room immediately.
This freezing injury to skin occurs most often in windy or wet conditions. It typically affects areas of the body that are exposed or have a limited blood supply, such as the nose, ears, fingers, and toes. Frostbitten fingers or toes are usually flushed. If the frostbite is severe, the affected skin will become hard, white or mottled, and numb.
As soon as you recognize any change in local skin color (especially in a vulnerable area) after being outdoors, take the following steps:
- Bring the person in from the cold as quickly as possible and remove any wet clothing.
- “Thaw” out the frostbitten part of the body by immersing it in warm (but not hot) water or applying warm moist compresses to it. (Use a bathtub if multiple areas are involved.) Do not use a heat lamp or electric heater, which might overheat and actually burn frostbitten skin. Numbness will usually disappear, and the normal skin color will return within a half hour. Pain may be felt as the affected areas rewarm; acetaminophen may be given if needed.
- Keep the rest of your child’s body comfortable with blankets or other warm clothing.
- Do not massage or rub snow on frostbitten areas of the body – this can cause damage to local tissue.
- If skin color and sensation are not normal within 20 to 30 minutes or if blisters develop in the frostbitten areas, seek medical attention.
The primary means of preventing hypothermia or frostbite is to dress appropriately for cold weather. Additional helps include the following:
- Because a significant amount of heat is lost from the surface of the head and because ears and fingers are particularly vulnerable to frostbite, make sure your child wears a hat or ear protection and mittens outdoors in cold weather.
- Multiple layers of clothing help prevent loss of body heat. Since wet clothing significantly increases heat loss, the outermost layer should be waterproof.