Frostbite occurs when exposure to extreme cold causes ice crystals to form in the cells of skin and the underlying tissue. Frostbitten areas turn hard and pale and become numb until re-warming. Mild cases of frostbite affect the skin and the underlying dermis; the area might feel oddly warm, and fluid-filled blisters might form in 24 to 36 hours after re-warming, says the Mayo Clinic. With severe frostbite, deeper tissue layers freeze, large blisters form, and the affected area turns black as the tissue dies.
Home Care
If frostbite is mild, it can be treated at home. Common sense measures include covering exposed areas, getting out of the cold and avoiding further tissue damage caused by pressure on frostbitten areas--such as rubbing the area to warm it--or walking on frostbitten toes. For mild cases of frostbite, the Mayo Clinic advises gentle re-warming of the affected area by immersion in warm water, about 104 to 107.6 degrees F, or wrapping it in a warm blanket.
Medical Re-warming
More severe cases of frostbite require medical intervention, with the first step of re-warming to thaw the affected tissue. Because the process can be painful, the doctor might give the frostbite patient pain medication beforehand. Medical re-warming is performed using immersion in warm water for 15 to 30 minutes, according to the Mayo Clinic. As the skin re-warms, it tingles or burns, softens and turns a red or purplish shade.
Debridement
In cases of severe frostbite, the damage can kill tissue. The dead tissue can impair the healing of the surrounding area, so doctors use a process called debridement to remove it. According to the Mayo Clinic, the doctor might wait for several months after the frostbite incident before starting debridement to better distinguish the areas of dead tissue from tissue that can return to health.
Whirlpool Therapy
For longer-term care of frostbite, whirlpool therapy can help with healing by gently removing dead tissue. The Merck Manual recommends three sessions per day in a whirlpool at 37 degrees C.
Medications
During re-warming, a doctor might give a frostbite patient opioid drugs for pain management. The Merck Manual says anti-inflammatory agents such as ibuprofen or keterolac can help during the acute recovery stage because during re-warming, blood factors called cytokines can set up an inflammatory response that can further damage the tissue. To improve blood flow during the acute phase, a doctor might give the drug phenoxybenzamine to reduce spasms in the blood vessels.
Surgery
For severe cases of frostbite that kills large areas of tissues, or deep layers of tissue, surgery might be necessary. Surgery can involve extensive debridement or amputation to remove the dead tissue.
