Thus, warming should not be attempted until the injured tissue can be kept warm. In order for frostbite to occur, the temperature must be 32 F or lower. Frostbite occurs at exposed areas of the skin such as the ears and nose but also may affect isolated spots such as the foot where skin is exposed. Frostbite of the fingers and toes is usually a result of prolonged, unexpected exposure to severe cold without proper protection. Hypothermic and dehydrated patients as well as tobacco users are more susceptible to frostbite.
Frostbite can be insidious in onset.
For instance, toes in a ski or hiking boot may feel cold and progress to paresthesia without the victim noticing. Once numb, unless intervention occurs, progression to frostbite can follow. Current therapy centers on gentle, continuous rewarming in 100-104 F water. Tissue should not be rubbed and should be protected from even the lightest trauma. Seattle, WA, The Mountaineers, 1966.