Our bodies carefully regulate our internal temperature to a precise degree. In hot weather, we sweat to cool off. In cold weather, we generate additional heat by shivering. However, prolonged exposure to cold can cause the body's control mechanisms to fail. When internal body temperature drops below 95 degrees Fahrenheit, the result is hypothermia. Hypothermia can lead to loss of consciousness, cardiac arrest, and death, if untreated.
Keep in mind that it doesn't have to be a chilly day for you to be at risk for hypothermia. The condition can also occur during mild weather if you get wet and exhausted.
Because hypothermia can cause mental confusion, people experiencing the first signs and symptoms may not realize that they need emergency medical treatment. Hypothermia may also go unrecognized at first because the symptoms show up gradually as internal body temperature falls. So be alert, especially when you are outside in cold temperatures.
Older adults, infants, and young children are at higher risk of developing hypothermia when exposed to the cold, because their bodies are less able to generate heat. People who are very lean may develop hypothermia more quickly than people with excess body fat. Malnutrition, cardiovascular disease, having an underactive thyroid, and recent alcohol consumption or alcohol intoxication may also increase the risk.
What to look for
The signs and symptoms of hypothermia include:
- Uncontrollable shivering
- Slurred speech
- Abnormally slow breathing
- Cold, pale skin
- Loss of coordination or consciousness
- Irrational behavior or apathy
- Weak, irregular or non-existent pulse
Note: On very cold days, hypothermia may go hand-in-hand with frostbite.
What to do
Swift action can warm the body and limit the risk of developing complications or irreversible damage from hypothermia. In extreme cases, acting rapidly can save lives.
First, remove any wet clothing. If possible, bring the person experiencing hypothermia indoors. If that's not possible, shield his or her body from the wind, cover the head, and insulate the body from the cold with blankets. If possible, place a blanket or other insulating material under the victim.
Dial 911 or call for emergency medical assistance.
If breathing seems dangerously slow or stops altogether, begin cardiopulmonary resuscitation (CPR) immediately.
Don't apply direct heat such as hot water, a heating pad, or a heating lamp. If possible, apply warm compresses to the neck, chest wall, and groin -- this will warm the person's blood as it flows through the core of the body and out into the arms and legs. Don't make the mistake of applying the compresses to arms and legs. Warming blood vessels in limbs this way can force cold blood to rush to the core of the body, causing a drop in the internal temperature and worsening the situation.
Do not massage or rub the person. People with hypothermia need to be handled gently, because they're at risk of cardiac arrest. Instead, use your own body to warm the victim.
Do not give the victim alcohol. Instead, offer sips of a warm nonalcoholic, sweetened beverage, such as tea. For mild cases of hypothermia, a sweetened drink produces a quick release of sugar into the bloodstream that results in increased heat and energy.
How to protect yourself from hypothermia
Always wear adequate clothing during winter. Do not travel in cold weather when the roads are dangerous. If you must travel, alert others that you are leaving and say where you are going. If you live in a cold-weather climate, carry a blanket in the car.
Handbook of First Aid and Emergency Care, American Medical Association.
American College of Emergency Physicians, First Aid Manual. DK Publishing.
Curtis, Rick. Outdoor Action Guide to Hypothermia and Cold Weather Injuries. National Ag Safety Database. http://www.cdc.gov/nasd/docs/d001201-d001300/d001216/d001216.html