Hypothermia occurs when your body temperature drops way below normal, causing the circulatory, respiratory, and nervous systems to slow down. Normal body temperature is around 98.6 °F; if your temperature drops to 95 °F or below, you are hypothermic. Hypothermia often happens gradually, but it can happen within minutes -- if, for example, someone falls through the ice into cold water. Then your body starts to lose heat faster than it can produce it. Severe hypothermia can cause an irregular heartbeat, which can lead to heart failure and death. More than 700 deaths occur annually from hypothermia in the United States.

• Skin that is cold to the touch
• Shivering at first, then the absence of shivering
• Lethargy, drowsiness
• Weakness, clumsiness
• Irritability, combativeness
• Confusion, delirium, hallucinations
• Slow reflexes
• Seizure, stupor, or coma
• Slowed, shallow, or arrested breathing
• Slowed, irregular, or arrested heartbeat

Hypothermia can happen from accidental exposure to cold, to immersion in cold water, or to trauma from a serious accident. Wearing wet clothes can raise your risk of hypothermia. Elderly people are especially susceptible. Hypothermia may develop over hours or days if your body can’t regulate heat as it should, if you can’t sense how cold it is, or if you live in a cold environment in the winter. Diseases of the endocrine glands may also cause your body to have trouble producing heat.

Risk factors include:

• Exposure to cold
• Immersion in cold water
• Severe trauma, especially brain injury or burns
• Not moving for long periods of time
• Age-related physical problems. More than half of all hypothermia-related deaths occur in people over age 65
• Pre-existing disease such as heart failure, pulmonary infection, other toxic infections, or endocrine disorders
• Dehydration
• Drugs such as alcohol, tranquilizers, sedatives, hypnotics, or antipsychotics
• Poverty, malnutrition, or homelessness
• Mental impairment that causes someone to be unaware of cold

Severe hypothermia is a life-threatening condition. If you or someone you care for has symptoms of hypothermia, give first aid to warm them up and call 911 immediately.

Prevention

You can usually prevent hypothermia by dressing warmly, being careful to stay warm and dry, and recognizing the early symptoms. If you plan to be outdoors for long periods in cold weather, wear layers of insulated or moisture-wicking clothing, including a hat. Keep emergency supplies in your car when traveling. Avoid overexertion, eat enough food, drink enough fluids, and do not drink alcohol. Social service agencies can help people who are prone to hypothermia, such as the elderly or the homeless, find housing, heat, and clothing. If you have elderly family members or neighbors, check on them when it’s cold.

Treatment Plan

Mild hypothermia can be treated by warming the person. Get out of the cold and remove wet clothing and replace it with dry, warm clothing and blankets. Give the person something warm to drink, but do not give alcohol. Other techniques include using hot water bottles, warm baths, or heat packs placed under the arms and on the chest, neck, and groin. Do not warm the arms and legs directly; this can force cold blood back toward the heart. Do not apply heating pads or heating blankets, and don’t rub arms and legs.

Sharing body heat (lying with your skin touching the person’s skin) may help. The person can also get into the heat escape lessening position (HELP), sitting with knees bent upwards so they are against the chest. This helps keeps the body’s trunk warm.

Watch the person’s breathing. If they stop breathing and have no pulse, give CPR if you are trained to do so. Use caution, however, because a person with hypothermia may have a very slow heart rate. You may need to check for a pulse for as long as 45 seconds or a minute.

At the hospital, the medical team will use heated intravenous fluids. The person may be wrapped with blankets in a warm room or put into a large tub of warm water.

Drug Therapies

In severe or complicated cases of hypothermia, intravenous drug therapy may be used.

Complementary and Alternative Therapies

Some nutritional tips may lower your risk for hypothermia. Animal studies suggest that some herbs may affect body temperature and may help prevent hypothermia if used before, or just after, exposure to cold.

Always tell your health care provider about the herbs and supplements you are using.

Nutrition and Supplements

These nutritional tips may help reduce symptoms of cold exposure:

• Eat warming spices in your foods, such as basil, ginger, turmeric, garlic, and cayenne.
• Eat antioxidant foods, including fruits (such as blueberries, cherries, and tomatoes), and vegetables (such as squash and bell peppers).
• Eat more hot soups made with fresh vegetables.
• Avoid coffee and other stimulants, alcohol, and especially tobacco. Tobacco causes blood vessels to constrict and may increase risk to hypothermia.
• Drink 6 - 8 glasses of filtered water daily. Hydration is important in reducing problems from cold exposure.
• Exercise at least 30 minutes daily, 5 days a week.

Keeping your body healthy may help ward off hypothermia. The following supplements are for general health:

• A multivitamin daily, containing the antioxidant vitamins A, C, E, the B-vitamins and trace minerals, such as magnesium, calcium, folic acid, zinc, and selenium.
• Omega-3 fatty acids, such as fish oil, 1 - 2 capsules or 1 tablespoonful oil one to two times daily, to help decrease inflammation and improve immunity. Cold-water fish, such as salmon or halibut, are good sources. Fish oil can increase the risk of bleeding. If you take blood-thinning medication such as warfarin (Coumadin) or aspirin, talk to your doctor before taking fish oil supplements. Eating fish does not cause any problems.

Herbs

The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, can trigger side effects and can interact with other herbs, supplements, or medications. For these reasons, you should take herbs only under the supervision of a health care provider.

You may use herbs as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, you should make teas with 1 tsp. herb per cup of hot water. Steep covered 5 - 10 minutes for leaf or flowers, and 10 - 20 minutes for roots. Drink 2 - 4 cups per day. You may use tinctures alone or in combination as noted.

These herbs may help prevent hypothermia. Do not give herbs or supplements to anyone who is already suffering from hypothermia.

• Panax ginseng (Panax ginseng) standardized extract, 100 - 200 mg twice daily, for preventing symptoms of cold exposure. You can also make teas from this herb.
• Green tea (Camellia sinensis) standardized extract, 250 - 500 mg daily, for antioxidant, anti-inflammatory and cold protective effects. Use caffeine-free products. You may also prepare teas from the leaf of this herb.
• Bilberry (Vaccinium myrtillus) standardized extract, 80 mg two to three times daily, for antioxidant and vascular system support.
• Ginkgo (Ginkgo biloba) standardized extract, 40 - 80 mg three times daily, for antioxidant support and cold protection. Ginkgo can increase the risk of bleeding. If you take blood-thinning medication such as warfarin (Coumadin) or aspirin, talk to your doctor before taking ginkgo.
• Herbal teas may help in reducing symptoms of cold exposure. Use herbs such as chamomile (Matricaria chamomilla) and ginger (Zingiber officinalis).

Homeopathy

Few studies have examined the effectiveness of specific homeopathic remedies. A professional homeopath, however, may recommend one or more of the following treatments for hypothermia based on their knowledge and clinical experience. Before prescribing a remedy, homeopaths take into account a person’s constitutional type -- your physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors when determining the most appropriate remedy for a particular individual.

• Aconitum -- very useful remedy when used just following exposure to cold, including in cases of shock and when extremities are cold, tingling, or numb.
• Arnica -- important homeopathic remedy for first aid, particularly in the case of shock and following trauma.
• Carbo vegetabilis -- for icy cold, bluish skin, particularly when the person is weak, sluggish, close to fainting, and short of breath.
• Cuprum metallicum-- for bluish discoloration of the skin accompanied by muscle cramps.

People with mild hypothermia usually recover with no lasting damage. However, people with moderate-to-severe hypothermia can face serious complications and even death. Children are more likely to recover from severe hypothermia than adults. The death rate for hypothermia in the elderly is about 50%. There are many possible complications from hypothermia, including hypoxia (lack of oxygen in the tissues), frostbite leading to gangrene in the hands and feet, inflammation of the pancreas, fluid in the lungs, pneumonia, kidney failure, and heart irregularities.

People with severe hypothermia should be hospitalized. They may need CPR. They should be transported very carefully and watched closely for an irregular heartbeat, which could be fatal. Normal body temperature in the elderly should be restored slowly, or permanent low blood pressure may result. All people with hypothermia must be watched closely until their body temperature returns to normal.

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