How To Treat Hypothermia

Hypothermia is defined as a drop in core body temperature to less than 35 degrees Celsius (95 degrees Fahrenheit) and can be further classified as mild (32 degrees Celsius to 35 degrees Celsius), moderate (28 degrees Celsius to 32 degrees Celsius), or severe (< 28 degrees Celsius) based on specific body temperature. Temperature is regulated through the hypothalamus in the brain. In normal circumstances, the hypothalamus senses deviations in temperature and makes changes to core body temperature accordingly. However, in hypothermia, there is a disturbance in this mode of temperature regulation, resulting in a drop in core body temperature.

There are several potential medical causes of hypothermia, including complications of diabetes (diabetic ketoacidosis, hypoglycemia), hypothyroidism, burns, head trauma, and stroke. Most people attribute hypothermia to certain environmental exposures such as immersion in cold water, prolonged time in a cold environment, or inadequate indoor heating. Elderly persons are at increased risk for hypothermia because they lack the ability to detect temperature changes and have trouble generating heat because of low body mass or impaired mobility. In the elderly, hypothermia can be easily caused by a cold environment, such as air conditioning or ice baths.

Symptoms of hypothermia are varied, depending on the severity. For mild hypothermia, signs include confusion, shivering, increased blood pressure, and increased heart rate. As hypothermia becomes more severe, signs include a decreased level of consciousness, fatigue, loss of shivering mechanism, hallucinations, decreased heart rate and blood pressure, and possibly coma and kidney failure. If moderate or severe hypothermia is suspected, it is best to take the individual to the nearest emergency department for treatment, as more invasive measures are needed to regulate the core body temperature.

To treat hypothermia, the individual must be rewarmed. For mild hypothermia, passive external rewarming is utilized. This consists of provision of insulation and a warm environment, such as using blankets or the addition of clothing. A disadvantage to passive external rewarming is that it is a slow process and relatively tedious. Additionally, individuals with mild to moderate hypothermia can be rewarmed through active external rewarming, in which heat is applied directly to the skin. This can be accomplished through forced warmed air, radiant heat, or electric blankets. In cases of moderate to severe hypothermia, active internal rewarming is most effective and is done in the hospital using modalities such as heated humidified air, warmed intravenous fluids, and blood rewarming.

For hypothermia that is relatively mild, it is safe to use blankets or additional clothing to attempt to rewarm the individual. However, for more severe cases, it is best to take the individual to the hospital to avoid serious complications.