SciTech

Health Talk: Frostbites

During the cold winter months, frozen extremities are fairly common occurrences. Low temperatures and biting winds cause extreme discomfort and can be painful. Many people experience frostbite at some point during their lives, if not during their college career in Pittsburgh. However, frostbite, if not taken seriously, can have severe consequences.

Frostbite occurs when layers of skin freeze when the tissues are exposed to a climate that is below the freezing point of skin, which is approximately -15° degrees Celsius, or 5° degrees Fahrenheit. The brain then sends messages to the vessels that supply blood to the tissues of the nose, fingers, toes, and ears (or wherever the frostbite is occurring), telling them to constrict. This in turn causes a decrease in blood flow to the affected extremities. Blood, though, is vital in keeping body parts warm. Therefore, if there is less blood flowing to extremities, then more blood is available for vital organs, keeping them warm instead, and leaving the extremities to freeze.

Frostbite due to prolonged exposure to extreme weather conditions can cause necrosis, or death of cells. There are two ways in which this can occur. The first is when necrosis occurs upon immediate exposure, due to the formation of ice crystals in the space surrounding the cells. This loss of water causes osmosis from the inside of the cell outwards. The dehydration of cells subsequently results in cell death. The second way necrosis happens is when damaged blood vessels result in the inflammation of tissues. This also causes a lack of oxygen in the tissues, and once again, cell death.

Superficial frostbite is a commonplace affliction. Symptoms include itching, burning, redness, and numbness in the affected areas. Deep frostbite is noted by blisters over whitened, frozen skin; the skin appears waxy and turns almost purple in color as it warms up. In addition, the skin remains hard and sometimes can appear blackened and dead.

Pain is also a symptom of frostbite, especially when blood returns to the affected areas. Moreover, frostbite can set in over time. That is, tissues may initially appear healthy and unaffected, but symptoms can appear much later, even as long as one to two days.

Frostbite frequently occurs in alcoholics, drug addicts, and people suffering from mental illness, because many of these individuals are often dehydrated or suffer from decreased blood flow. Men aged 30 to 49 are also very susceptible, as are people with bad circulation and diseases such as diabetes.

However, it is fairly easy to prevent frostbite. It’s important to keep the body covered and try to avoid prolonged exposure to extreme temperatures: Wear gloves, a scarf, and especially a hat, since 30 to 50 percent of heat lost is through the head. Also, keeping the body dry is crucial; as such, wearing fabrics that keep moisture away from skin is a must. Wearing loose layers is the best idea; impeded blood flow due to tight clothes can increase susceptibility to frostbite. Moisturizing the skin before going outside can also help, as can hand warmers from those days of cheering from the bleachers at football games or waiting in line at the ice rink.