Frostbite is a tissue injury induced by exposure to cold. Frost bite happens when a person is exposed to extreme cold leading to damage of the skin and the underlying tissue. Any part of the body may be affected by frostbite but it usually occurs in the nose, ears, fingers and toes.
When the temperature reaches zero or below, the blood vessels located close to the skin start to constrict to decrease the blood flowing throw them which in turn will lead to decrease heat loss and preserve core body temperature (see regulation of body temperature). When the skin and the underlying tissues are exposed to prolonged cold or extreme cold, the flow of blood to the affected areas will be greatly reduced leading to damage to these areas which may be permanent leading to tissue death and amputation in severe cases.
The risk of frostbite increases in the following:
- Persons who use medications that decrease the blood flow to the skin such as beta-blockers.
- Persons with peripheral vascular disease which decrease the blood flow to the affected tissue.
- People with peripheral neuropathy which decreases the ability to feel injuries.
- Smoking and diabetes.
- High velocity wind which increases the rate of heat loss from the skin.
- Persons who are not well dressed for extremely cold temperature.
Signs and symptoms:
- Each individual may experience symptoms differently; the signs and symptoms depend on the severity
- Pins and needles sensation followed by mild numbness.
- Redness and pain in the affected skin area.
- Firm or waxy skin which is white and completely numb (a sign that tissues have started to freeze).
- Skin blisters.
- Very severe frost bite may cause gangrene (blackened, dead tissue) and damage to the deep structures such as muscles and nerves.
This information is not intended nor implied to be a substitute for professional medical advice; it should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. Call 911 for all medical emergencies.