Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.
A variety of frostbite classification systems have been proposed. The easiest to understand, and perhaps the one that gives the best clues to outcome, divides frostbite into
two main divisions: superficial and deep.
In superficial frostbite, you may experience burning, numbness, tingling, itching, or cold sensations in the affected areas. The regions appear white and frozen, but if you press on them, they retain some resistance.
In deep frostbite, there is an initial decrease in sensation that is eventually completely lost. Swelling and blood-filled blisters are noted over white or yellowish skin that looks waxy and turns a purplish blue as it rewarms. The area is hard, has no resistance when pressed on, and may even appear blackened and dead.
The affected person will experience significant pain as the areas are rewarmed and blood flow reestablished. A dull continuous ache
transforms into a throbbing sensation in 2 to 3 days. This may last weeks to months until final tissue separation is complete.
At first the areas may appear deceptively healthy. Most people do not arrive at the doctor with frozen, dead tissue. Only time can reveal the final amount of tissue damage.
There are milder conditions related to frostbite, including frostnip,
chilblains, and trench foot.
Frostnip refers to the development of paresthesias (tingling sensations)
that occur due to cold exposure. They disappear upon rewarming without any
Chilblain (or pernio) refers to a localized are of tissue inflammation that
appears as swollen and reddish or purple. These develop in response to repeated
exposure to damp, cold conditions above the freezing point. Chilblains may itch
or be painful.
Trench foot was described in World War I as a result of repeated exposure
to dampness and cold and exacerbated by tight boots. The affected feet are
reddened, swollen, painful or numb, and may be covered with bleeding blisters.
This condition is still observed in some homeless persons today.