Frostbite

Key Points
Condition in which the skin and possibly underlying tissue freezes due to exposure
Cases may vary between mild and severe
Consists of reddened, painful or whitened, numb skin. Severe cases may be accompanied by blistering, hardening, and the development of gangrene

Frostbite is a condition in which skin freezes due to exposure. Frostbite begins as a painful reddening of the affected skin, which then gives way to numbness and skin which turns white. Continued exposure leads to blistering or blackening of the skin, which also becomes hard due to the freezing of blood vessels and bones. In extreme cases, it may develop into gangrene as tissue death occurs. Frostbite most commonly occurs on areas of the skin which are exposed to cold, including the face, ears, and extremities.

Frostbite is caused by prolonged exposure to extreme cold. Those persons who find themselves in cold climates or are exposed to cold temperatures consistently are most at risk for its development. Those persons with poor circulation, suffering from fatigue, or wearing tight fitting clothing or footwear are at an increased risk. Alcohol and tobacco use may increase this risk.

Differential Diagnosis (Other conditions with similar appearance)

Hypothermia
Pernio (Chilblains)
Trench foot

Diagnosis
Key Points
Diagnosis based on appearance of the affected skin in conjunction with history of patient exposure

Frostbite is diagnosed based on the appearance of the affected area, in conjunction with the knowledge that the patient has been exposed to extremely cold temperatures.

Treatment
Frostbite should be treated by health care professionals
First aid measures can assist in preventing further development of the condition while health care professionals are contacted
*In severe cases or cases accompanied by hypothermia, emergency medical personnel should be contacted immediately

Frostbite should be treated by health care professionals, however, first aid measures are available to assist in mild cases while treatment is sought. It is recommended that the affected person be moved to a warmer area if possible, and clothing be removed from the affected area. It is important that skin be rewarmed, either by submersion in warm, not hot, water or the application of warm compresses to the area if submersion is not possible. This should continue for approximately 30 minutes, and may be accompanied by pain and swelling. After covering the area with a clean dressing, the area should be covered with dry clothing to retain warmth.

In severe cases, or cases which are accompanied by hypothermia, emergency medical care should be sought immediately. Health care professionals will attempt to warm the affected area, and may administer painkillers to alleviate any pain which may accompany the rewarming process. Affected areas will be dressed and elevated to prevent further damage to tissue. If an area becomes infected, antibiotics will be administered. In severe cases of infection or when tissue has become gangrenous, excision will be utilized to assist in eliminating the infection and removing dead tissue.