Cold Hands and Feet

When your hands or feet (and sometimes other parts of the body, especially your ears and nose) get too cold, they can be injured or react in different ways.

• The most severe cold injury is frostbite, which is true tissue freezing (ice crystals form in the skin and other tissues of the body). Frostbite causes permanent damage to blood vessels and other structures. Frostnip is also ice crystal formation in tissues but only in the very outer layer of the skin. It causes no permanent damage.
• Immersion injury results from exposure of wet feet (or hands) to cold temperatures at or above freezing. It develops over hours to days and damages the nerves and muscles. Like frostbite, immersion injury causes permanent damage.
• Other conditions of cold hands or feet are pernio, Raynaud's phenomenon, cryoglobulin formation, and cold urticaria.

Humans are tropical animals. We are adapted to a warm climate. When exposed to cold, the body tries to stay warm. If the body is cooling off, circulation decreases in the arms, legs, ears, and nose so that the rest of the core body can stay warm. When temperatures are below freezing, ice may form in these areas with less circulation.

• Nonfreezing cold injuries are also caused by cooling of the skin. In immersion injuries, the nerves and blood vessels are damaged after exposure to cold, wet conditions at or above freezing temperatures.
• Pernio is caused by exposure to cold for a long period of time without freezing or by very wet conditions.
• Raynaud's phenomenon is an abnormal narrowing of the blood vessels that constrict with cooling of the fingers or toes.
• Cryoglobulins are proteins, which are normally dissolved in the blood, that become solids or gels when cold. Cryoglobulinemia is the condition associated with cryoglobulins in the blood, whereby cold exposure leads to bluish discoloration of the fingers or toes.
• The formation of hives in response to cold exposure of the skin is called cold urticaria.

• Frostbite and frostnip
  • Frostbitten body parts are white and hard or waxy. They may be white-purple or white-yellow.
  • Frostnipped parts are white but not hard and are generally very small areas.
  • Frozen parts have no feeling.
  • During the freezing process, they may tingle or feel like a block of wood.
  • Once frostbitten areas thaw, they may be painless or tingle.
  • When they are rapidly rewarmed in warm water by the recommended method, they may be painful.
  • Over the next few days, the part is often painful and swollen.
  • Blisters may appear, and severely affected areas turn black.
• Immersion injury
  • Areas affected by immersion injury are first red and then turn pale and swollen.
  • Numbness or painful tingling may occur.
  • After the first few days, the part becomes very red, tingling, swollen, and may have blisters, skin breakdown, or even liquefy.
• Pernio
  • Pernio is a rash on the lower legs, feet, toes, hands, or ears that may be red or blue and may form scaly areas or lumps.
  • Rarely, affected parts may bleed, blister, or have skin breakdown.
  • Often pernio causes itching and burning.
• Raynaud's phenomenon refers to constriction of the blood vessels of the hands or feet in response to cold exposure. Raynaud's phenomenon causes white, then blue, then red-colored fingertips and toes and is often painful.
• Cryoglobulins cause a wide array of symptoms, depending on whether or not internal organs are involved, including deep-blue fingertips.
• Cold urticaria refers to raised red bumps or hives produced in response to cold exposure.

If you suspect that you have frostbite or immersion injury, do not call the doctor. Go to a hospital's emergency department. If you suspect that you have pernio or other cold-induced injuries, you should call your doctor.

If you have any white hard areas on hands, feet, or other parts of the body or if you had white areas that have thawed, go to the emergency department for treatment of frostbite.

If your hands or feet have been cold and wet for an hour or longer, you may have immersion injury and should also go to the emergency department.

If a part of your body that has been exposed to cold is painful, go to the emergency department.

Frostbite is diagnosed by the way it looks, not by tests. There are no specific tests for other conditions caused by cold, except blood tests for cryoglobulins. As with frostbite, testing may be needed for other injuries or conditions.

• If there are other injuries such as hypothermia (below normal body temperature) or possible broken bones, tests may be needed for the other injuries.
• If the frostbite seems severe, a bone scan may be necessary. This is a painless procedure that shows the doctor which areas of the hands or feet still have circulation.
• Other tests often done for frostbite include blood tests, especially tests of the tendency of the blood to clot, and X-rays.

Home care should only be done under the instructions of a physician.

• Home care for frostbite or immersion injury
  • Keep the area clean and dry
  • Elevate the area
  • Avoid refreezing
  • Protect the area from pressure or rubbing
  • Warming frostbite should not be done at home unless you have no alternative (such as impassable roads due to a snowstorm).
    • In that case, the water should be 99-104 F.
    • The body part should not touch the side or bottom of the sink or bathtub.
    • A hot tub is a good alternative, even if a little warmer than the ideal temperature.
• Home care for frostnip
  • Warming frostnip can be done in the shower or sink or with a warm washcloth on the face or ears.
  • Only rewarm at home if you are sure it is just frostnip (small superficial area, skin still flexible). If you think you may have frostbite, rewarming is better performed in the emergency department.
  • When the part being warmed flushes (returns to normal color), you can remove it from the water. This generally takes less than a half hour.
  • Do not use other warming devices, such as an electric blanket, heating pad, or placing the affected part under running tap water. Your body part lacks feeling when it is frostnipped, and you may burn yourself without realizing it.
  • The area will heal completely but may remain sensitive for weeks after the injury.
• Home care for other cold injuries generally includes avoidance of cold exposures and wearing adequate protective clothing when going outdoors in cold conditions.

• If you come to the emergency department and still have any white areas of frostbite, the doctor will begin rapid rewarming in water that is slightly above body temperature. The frozen parts are thawed until they are pink, which shows that the circulation has returned.
  • If the warmed area is only a little red, you may be allowed to go home with instructions about how to protect the injured area. If you have only clear blisters that go to the ends of the fingers and toes along with swelling and some pain, you may also be allowed to return home with instructions. If you have dark blisters, no swelling, or no circulation in the warmed area, you will be hospitalized.
  • In either case, you may be asked to take aspirin or ibuprofen (Advil), which may protect against further injury to the area from substances that are released from damaged cells. You may also be given other medications to help the circulation of blood and to assure good nutrition.
  • If you are hospitalized, the injured areas will be wrapped most of the time and elevated. Twice a day they will be unwrapped and placed in a whirlpool to remove bacteria and dead cells that build up on the surface of the skin. If frostbite is severe, it may be necessary to remove some of the dead areas by amputation.
• Immersion injury is treated like frostbite, although initial thawing in warm water is not necessary.
• Frostnip is treated by rewarming the area and protecting it from further cold exposure.
• Treatment of pernio is the same as for frostbite: rewarming the area, washing, drying, sterile dressings, and elevation. Pain medicine may be needed.
• Raynaud's phenomenon is treated by avoiding cold exposure and sometimes by medications that relax the blood vessels to avoid the narrowing that occurs in response to cold.
• Cryoglobulins are treated by avoiding cold exposure, not standing for prolonged periods and, in severe cases, plasmapheresis (removal of proteins from the blood).
• Cold urticaria may respond if you avoid cold. Sometimes medications may be necessary.

Follow-up care for cold injuries includes the following:

• Protect the injured area from further damage.
• Elevate the injured area.
• Take medications as prescribed by the doctor.
• Practice good nutrition.
• Avoid smoking.
• Check the wound periodically.
• Infection: If there are any signs of infection, such as increased pain or redness, increased swelling, fever, pus, or red streaks on the skin, you should return to the emergency department or your doctor's office immediately.

The best way to avoid cold injuries is to wear adequate clothing when venturing outdoors in the cold.

• Especially in windy conditions, protect the face, hands, and feet.
• Using hand-warmer packs, such as those used by skiers, can be helpful when out in colder weather for prolonged periods.
• Avoid tight-fitting clothing.
• Mittens are warmer than gloves.
• Do not wear extra pairs of socks if they make shoes or boots fit too tightly.
• Keep hands and feet dry.
• If possible, seek shelter during extreme cold.
• Physical activity with adequate food intake will help keep your hands and feet warm.
• Do not smoke, because smoking decreases the circulation to hands and feet.

• Severely frostbitten areas may require amputation. Frostbitten areas that recover are prone to excessive sweating, pain, coldness, numbness, changes in skin color, and stiffness. Frostbite in children may lead to growth abnormalities of the affected part.
• Frostnipped areas recover without any difficulties, except that they may be sensitive to the cold for months or years.
• Areas with immersion injury may also require amputation. Affected areas remain sensitive to cold for years and may have all the problems associated with frostbite.
• Areas of pernio usually recover within two weeks. Sometimes the rash may last longer. The skin may darken permanently. Pernio may come back if you are exposed to cold again.
• Raynaud's phenomenon tends to be intermittent. It can usually be handled if you avoid exposure to cold, but medication may be of benefit for those who are unable to avoid cold temperatures.
• People with cryoglobulins may have minor symptoms such as cold intolerance and finger discoloration to severe, life-threatening symptoms such as kidney failure or stroke. Cryoglobulins are not common.
• Cold urticaria can usually be controlled by avoidance of cold but sometimes requires medication.