Know the signs of hypothermia

Q: What are the signs and symptoms of hypothermia?

A: As the weather gets colder, our risk for hypothermia increases. It occurs when body temperature (normally 98.6 degrees) drops below 95 degrees. If the body is not properly insulated, hypothermia can develop in a matter of hours.

Symptoms of hypothermia include poor judgment, confusion, and difficulty maintaining balance. As hypothermia progresses, shivering will stop as the body tries to conserve energy. In some cases, people may begin to feel very warm and remove their clothing in a phenomenon called "paradoxical undressing." Heart rate and blood pressure fall until the heart and lungs ultimately fail.

Those at greatest risk for hypothermia are the very young, the elderly, those with endocrine disorders such as hypothyroidism, and those with neurodegenerative diseases such as Parkinson's or Alzheimer's. Those who consume alcohol may also be at risk - alcohol makes the body feel warm temporarily, but it also causes blood vessels to dilate, speeding the process of heat loss. Be sure to regularly check on any loved ones who have these risk factors.

To prevent cold injury and lower the risk of hypothermia, it is important to keep your head, face, neck, and hands covered when you're outdoors in the cold. Avoid activities that cause profuse sweating, as wet clothing can also speed the process of heat loss. In addition, be sure to dress in loose-fitting layers, and stay as dry as possible. Finally, avoid alcohol if you know you will be outdoors for long periods.

- Gregory McDonald, D.O., is professor and chair of forensic medicine
and pathology at the Philadelphia College of Osteopathic Medicine.