Frostbite is a skin injury that occurs when exposed to extreme low temperatures, causing the freezing of the skin or other tissues, commonly affecting the fingers, toes, nose, ears, cheeks and chin areas. Most often, frostbite occurs in the hands and feet. The initial symptom is typically numbness. This may be followed by clumsiness with a white or bluish color to the skin. Swelling or blistering may occur following treatment. Complications may include hypothermia or compartment syndrome.People who are exposed to low temperatures for prolonged periods, such as winter sports enthusiasts, military personnel, and homeless individuals, are at greatest risk. Other risk factors include drinking alcohol, smoking, mental health problems, certain medications, and prior injuries due to cold. The underlying mechanism involves injury from ice crystals and blood clots in small blood vessels following thawing. Diagnosis is based on symptoms. Severity may be divided into superficial (1st and 2nd degree) or deep (3rd and 4th degree). A bone scan or MRI may help in determining the extent of injury.Prevention is by wearing proper, fully-covering clothing, maintaining hydration and nutrition, avoiding low temperatures, and minimizing strenuous physical activity while maintaining a sufficient core temperature. Treatment is by gradual rewarming, generally from cold to warm water, and should only be done when consistent temperature can be maintained and refreezing is not a concern. Rapid heating or cooling should be avoided since it could potentially cause heart stress or cause burning.
The Florida Department of Health has added NSP to their list of reportable diseases. Additionally, since the mid-1970s the Florida Department of Environmental Protection has conducted monitoring of dinoflagellate levels and restricted the harvest of shellfish from nearby shellfish beds when levels are dangerously elevated. Shellfish beds are subsequently opened after two weeks with confirmation of safety by mouse bioassay testing (mouse bioassay testing involves the injection of mice with shellfish extract with subsequent observation for mouse death). See also
Amnesic shellfish poisoning
Diarrheal shellfish poisoning
Paralytic shellfish poisoning
Ciguatera fish poisoning


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