An abnormal and potentially serious physical condition that is caused by exposure to cold temperatures. Cold injuries range from frostbite and pernio to hypothermia. Frostbite occurs when tissue freezes. Blood vessels are deprived of oxygen, leading to edema (swelling] and necrosis (tissue death). Treatment is with gentle warming, such as immersion into warm bath water. Affected body parts should not be rubbed. Chilblains (see pernio), a condition in which there is constriction of small blood vessels because of cold weather, causes burning, itching, and ulceration similar to that caused by burns; treatment is the same as for frostbite.
Cold injury is a condition characterized by localized tissue damage resulting from the chilling of a specific part of the body. It should be noted that cold injury is distinct from hypothermia, which refers to the overall chilling of the entire body.
The most severe manifestation of cold injury is frostbite, which occurs when a specific area of the skin and underlying tissues freeze due to exposure to extremely cold and dry air. Affected areas become rigid, pale, and appear white. In some cases, blood supply to the affected area may be compromised. Another type of injury, known as immersion foot, arises when the legs and feet are exposed to cold and wet conditions for prolonged periods. The primary risk associated with both conditions is the potential slowing down of blood flow to such an extent that the tissues become necrotic and develop gangrene. Less severe forms of cold injury include chilblains and chapped skin.