Generalized hypothermia occurs when the core body temperature falls significantly below 98.6 degrees Fahrenheit. There are several predisposing factors that can cause hypothermia and several symptoms of hypothermia that every EMT should be aware of.
Being exposed to cold environments can cause hypothermia. The greatest temperature risk for hypothermia ranges between 40 and 50 degrees Fahrenheit. This may not seem very cold but it has been determined to be the most dangerous temperature range because people often do not dress warmly enough at these temperatures. Lack of warm clothes can cause the core body temperature to drop significantly. Other factors associated with hypothermia include water, ice, and snow. Non environmental factors include metabolic, neurological, traumatic, toxic and infectious factors.
Alcohol can affect hypothermia because the consumption of alcohol can impair a person's judgment and physical condition. A person who has consumed too much alcohol may not seek shelter from the cold or may pass out in the cold. Alcohol also causes the blood vessels in the extremities to dilate, causing a rapid heat loss.
Old and young patients are particularly susceptible to hypothermia. Older patients tend to have less insulating fat and therefore less internal heat production. Also, there are many medications that can affect the older patient's respond to temperature changes. Young patients also tend to have less fat for insulation. Young children are less likely to seek protection from the cold. They are also less likely to put on more clothes if it is cold. Infants are unable to care for themselves and their bodies have immature temperature regulation mechanisms. This can make maintaining a normal body temperature more challenging.
Signs and symptoms of generalized hypothermia can be subtle. An EMT may notice shivering, the patient may complain of loss of sensation. There could be memory loss or dizziness as the hypothermia becomes more severe. The most important sign of hypothermia is a decrease in a patient's mental status and motor function.