Colder temperatures mean snow in the mountains of California, and everywhere in the mid-west and east coast. With an increase in outdoor winter activities and lack of appropriate, heated shelter for the homeless population, we are going to see an increase in cold related injuries at our burn centers.
There are three major categories of cold induced injury, frostnip, chilblain and frostbite.
Frostnip is a mild cold induced injury that produces local paresthesia (numbness, prickling or tingling) that completely resolves with passive external rewarming.
With chilblains (AKA erythema pernio), exposure to cold temperatures causes inflammatory changes in the skin without actual freezing of the tissues. Signs and symptoms of chilblains include painful, itchy, red or purple skin lesions with burning and parathesias. The lesions may blister and there may be local edema. Chilblains, though more severe than frostnip responds well to rewarming and does not require surgical intervention.
Frostbite is a cold induced injury that results in freezing and formation of ice crystals within the tissue. Frostbite may occur when the skin temperature drops below 24.8⁰F to 14⁰F. It can occur at higher temperatures in the presence of wind, immobility, malnutrition, or peripheral vascular disease. Early symptoms include; itching, numbness, prickling and pallor in the affected area. Indications of deeper tissue injury in more severe cases include; white or yellow appearance of the skin, decrease in elasticity and mobility of the skin. May progress to hemorrhagic blistering and necrosis with associated edema and stiffness. Severe cases of frostbite may result in major tissue loss and the need for amputation.