Frostbite severity is determined by the depth of the freezing and subsequent injury. Grading scales are sometimes used to guide therapy.
Diagnosis is clinical, but technetium-99m or magnetic resonance scanning can give an early indication of prognosis.
The mainstay of treatment is rapid initial rewarming of the injured tissue.
Being a thermal injury, wound management is similar to the management of burns and involves debridement of white blisters, regular aloe vera application, and regular hydrotherapy. Early therapy with a nonsteroidal anti-inflammatory drug is advised.
Emerging data suggest thrombolytic therapy may be of benefit in severe frostbite if given within 24 hours of injury. It is best given within 6 hours of injury.
It takes 1 to 3 months to determine the viability of the injured tissue and surgery should normally be delayed.
Risk factors for amputation include severe injury grades, late presentation, lower extremity involvement, and wound infection.
Frostbite is an injury produced by tissue freezing following exposure to cold. Frostbite requires temperatures of 32°F (0°C) or colder to occur.
History and exam
Key diagnostic factors
- cold or numbness of affected extremity
- pain during rewarming
- purplish skin discoloration
- white or yellow skin plaque
- superficial skin vesiculation
- deep purple blisters
- tissue necrosis and mummification (dry gangrene)
Other diagnostic factors
- joint dislocation
- cold exposure
- previous frostbite
- vascular insufficiency
- high altitude
- extremity trauma
- constrictive clothing or equipment
1st investigations to order
- clinical diagnosis
Investigations to consider
- technetium-99m pertechnetate scintigraphy
- magnetic resonance angiogram of affected extremity
- plain radiography
- thermography and duplex imaging
Elizabeth A. Kaufman, MD, CAQ-SM
Scripps Green Hospital
Urgent Care Center
EAK declares that she has no competing interests.
Christopher Imray, PhD, FRCS, FRCP, FRGS
Director of Research, Development and Innovation
University Hospital Coventry and Warwickshire NHS Trust
Warwick Medical School
CI has been paid for medico-legal work as a medical expert and receives royalties of approximately £150 per annum for the Oxford Handbook of Wilderness and Environmental Medicine. CI has spoken pro bono at lectures and other educational events.
Professor Christopher Imray and Dr Elizabeth A. Kaufman would like to gratefully acknowledge Professor Paul S. Auerbach and Dr Claire Turchi, previous contributors to this topic. PSA and CT declare that they have no competing interests.
Luanne Freer, MD, FACEP, FAWM
Yellowstone National Park
Everest Base Camp Medical Clinic
LF declares that she has no competing interests.
Grant S. Lipman, MD
Clinical Assistant Professor of Surgery and Emergency Medicine
Associate Director Wilderness Medicine Fellowship
Assistant Research Director
Stanford University School of Medicine
GSL declares that he has no competing interests.
Peter Hackett, MD
Institute for Altitude Medicine
PH declares that he has no competing interests.
- Cutaneous burns
- Raynaud phenomenon
- Heat illness and cold injury: medical management part 2 guidance
- Wilderness Medical Society clinical practice guidelines for the prevention and treatment of frostbite: 2019 update
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