Frostbite is a cold-related injury characterized by the freezing of tissue. It can result from prolonged exposure to moderate cold or brief exposure to extreme cold. Tissue injury is greatest when cooling is slow, cold exposure is prolonged, the rate of rewarming is slow, and, especially, when tissue is partially thawed and refreezes.
When exposed to the cold, the blood vessels in the skin constrict or tighten. This reduces the blood flow to the skin and underlying tissue, and ice crystals form in the fluid around the skin cells.
Frostbite most commonly affects the extremities e.g. fingers, toes, tip of the nose, ears and cheeks. It can be classified by degree of damage from first degree involving the most superficial layer of the skin to fourth degree which affects all the layers of the skin and the underlying tissue, even muscles and tendons.
Symptoms can include
- pain in the affected area
- numbness in the affected area
- prickly sensations
- firm, whitened skin areas
- peeling or blistering
- mottled skin (blotchy, red and white)
- hard, glossy, grayish, yellow skin
Any degree of frostbite needs treatment by re-warming, either in luke-warm water, or if not available, by placing next to a warm area of the body e.g. put your hands in your armpits!. Antibiotics may be needed either in creams or orally. Do not burst blisters; they provide a natural protective cover for the damaged area. If they burst spontaneously, cover the area with a clean dressing. Be prepared to elevate the affected area if swelling occurs.
Any affected area MUST be protected from further damage from sun and most importantly from the cold. The area will remain vulnerable to further thermal damage for an indefinite period.
- Avoid prolonged exposure to the cold
- Wear loose fitting clothes in several layers.
- Cover exposed areas e.g. ears, cheeks and hands with hats, scarves and gloves – mittens are better than gloves
- Change wet clothes immediately
- Avoid caffeine, tobacco and alcohol as they cause constriction of the small blood vessels, leaving the skin more liable to cold injury.
This article published on
28 November 2005
Next review date 01/11/2013
Skin and hair
Skin and hair