Frostbite

Considerations

A person with frostbite on the arms or legs may also have hypothermia (lowered body temperature). Check for hypothermia and treat those symptoms first.

Causes

Frostbite occurs when the skin and body tissues are exposed to cold temperature for a prolonged period of time.

You are more likely to develop frostbite if you:

• Take medicines called beta-blockers
• Have peripheral vascular disease
• Smoke
• Have diabetes
• Have Raynaud's phenomenon

Symptoms

Symptoms of frostbite include:

• Pins and needles feeling followed by numbness
• Hard, pale, and cold skin that has been exposed to the cold for too long
• The area may ache or throb.
• Lack of sensation; you may not feel it if someone touches you there
• As the area thaws, the flesh becomes red and very painful

Very severe frostbite may cause:

• Blisters
• Gangrene (blackened, dead tissue)
• Damage to tendons, muscles, nerves, and bone 

Frostbite may affect any part of the body. The hands, feet, nose, and ears are the most vulnerable.

• If the frostbite did not affect your blood vessels, a complete recovery is possible.
• If the frostbite affected the blood vessels, the damage is permanent. Gangrene may occur. This may require removal of the affected part (amputation).

First Aid

1. Shelter the person from the cold and move him or her to a warmer place. Remove any constricting jewelry and wet clothing. Look for signs of hypothermia (lowered body temperature) and treat accordingly.

2. If immediate medical help is available, it is usually best to wrap the affected areas in sterile dressings (remember to separate affected fingers and toes) and transport the person to an emergency department for further care.

3. If immediate care is not available, rewarming first aid may be given. Soak the affected areas in warm (never hot) water -- or repeatedly apply warm cloths to affected ears, nose, or cheeks -- for 20 to 30 minutes. The recommended water temperature is 104 to 108 degrees Fahrenheit. Keep circulating the water to aid the warming process. Severe burning pain, swelling, and color changes may occur during warming. Warming is complete when the skin is soft and sensation returns.

4. Apply dry, sterile dressings to the frostbitten areas. Put dressings between frostbitten fingers or toes to keep them separated.

5. Move thawed areas as little as possible.

6. Refreezing of thawed extremities can cause more severe damage. Prevent refreezing by wrapping the thawed areas and keeping the person warm. If protection from refreezing cannot be guaranteed, it may be better to delay the initial rewarming process until a warm, safe location is reached.

7. If the frostbite is extensive, give warm drinks to the person in order to replace lost fluids.

DO NOT

• Do NOT thaw out a frostbitten area if it cannot be kept thawed. Refreezing may make tissue damage even worse.
• Do NOT use direct dry heat (such as a radiator, campfire, heating pad, or hair dryer) to thaw the frostbitten areas. Direct heat can burn the tissues that are already damaged.
• Do NOT rub or massage the affected area.
• Do NOT disturb blisters on frostbitten skin.
• Do NOT smoke or drink alcoholic beverages during recovery as both can interfere with blood circulation.

When to Contact a Medical Professional

Call your doctor or nurse if: 

• You had severe frostbite
• If normal feeling and color do not return promptly after home treatment for mild frostbite
• Frostbite has occurred recently and new symptoms develop, such as fever, general ill-feeling, skin discoloration, or drainage from the affected body part

Prevention

Be aware of factors that can contribute to frostbite, such as extreme cold, wet clothes, high winds, and poor circulation. Poor circulation can be caused by tight clothing or boots, cramped positions, fatigue, certain medications, smoking, alcohol use, or diseases that affect the blood vessels, such as diabetes.

Wear suitable clothing in cold temperatures and protect exposed areas. In cold weather, wear mittens (not gloves); wind-proof, water-resistant, layered clothing; two pairs of socks; and a hat or scarf that covers the ears (to avoid substantial heat loss through the scalp).

If you expect to be exposed to the cold for a long period of time, don't drink alcohol or smoke, and get adequate food and rest.

If caught in a severe snowstorm, find shelter early or increase physical activity to maintain body warmth.

Alternative Names

Cold exposure - arms or legs

References

Danzl DF. Hypothermia and frostbite. In: Marx JA, ed. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, Pa: Mosby Elsevier; 2009:chap 137.

Danzl DF. Hypothermia and frostbite. In: Fauci AS, Harrison TR, eds. Harrison's Principles of Internal Medicine. 17th ed. New York, NY: McGraw Hill; 2008:chap 20.

Update Date: 1/8/2012

Updated by: Jacob L. Heller, MD, MHA, Emergency Medicine, Virginia Mason Medical Center, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.