Frostbite is tissue damage caused when skin is exposed to extreme cold, usually a temperature below minus 10 degrees Celsius. The extreme cold causes the blood vessels to constrict, which decreases blood flow and prevents sufficient heat from reaching the tissues. Without sufficient heat, ice crystals will form inside the tissues
Superficial Frostbite
Superficial frostbite is the milder form of frostbite. Fingertips, ears, nose and toes are the areas most commonly affected. According to "Sheehy's Emergency Nursing Principles and Practice" symptoms of superficial frostbite include tingling, numbness and a burning sensation. The skin will have a white, waxy color and feel cold and stiff. As the tissue thaws, the patient may complain of feeling a hot, stinging sensation. The areas affected will be discolored and develop blisters within a few hours. The skin that has been affected is susceptible and could easily develop frostbite again if exposed to cold temperatures.
Deep Frostbite
Deep frostbite effects not only the skin, but muscles, bones and tendons. In deep frostbite the affected area will appear as white or yellow-white in color, and is hard and cool. The patient will not have any feeling in the area involved. The patient will initially have a burning sensation which is followed by a feeling of warmth and then numbness. Blisters will appear anywhere between one to seven days after the exposure. Swelling will occur and may last for months after the injury. The skin will turn a black-grey color which will progress to death and decay of the tissue called gangrene. There is a high risk of infection in this injury.
Outcome
The tissues in superficial frostbite are very fragile, so they require gentle handling. Do not rub the area that is affected. The patient will need to be kept warm but any type of friction or weight, such as heavy blankets, can cause shedding of the injured skin. Deep frostbite requires strict medical attention to thaw the area. Thawing of frozen tissue is extremely painful for the patient. Patients will require pain medication and antibiotics are necessary because of the high risk of infection. The affected areas will need to be protected with large, soft bulky dressings. The final determination of the extent of injury may not be possible for several weeks. In some cases amputation of the extremity may be necessary.
References
- "Frostbite: Diagnosis, Pathophysiology, and Treatment"; Abraham & Young; Podiatry Management; 2007
- "Sheehy's Emergency Nursing Principles and Practice"; Mosby Elsevier; 2010
