Hyperthermia is an elevated body temperature due to failed thermoregulation. Hyperthermia occurs when the body produces or absorbs more heat than it can dissipate. When the elevated body temperatures are sufficiently high, hyperthermia is a medical emergency and requires immediate treatment to prevent disability or death.
The most common causes are heat stroke and adverse reactions to drugs. Heat stroke is an acute condition of hyperthermia that is caused by prolonged exposure to excessive heat or heat and humidity. The heat-regulating mechanisms of the body eventually become overwhelmed and unable to effectively deal with the heat, causing the body temperature to climb uncontrollably. Hyperthermia is a relatively rare side effect of many drugs, particularly those that affect the central nervous system. Malignant hyperthermia is a rare complication of some types of general anesthesia.
Hyperthermia can be created artificially by drugs or medical devices. Hyperthermia therapy may be used to treat some kinds of cancer and other conditions, most commonly in conjunction with radiotherapy.
Hyperthermia differs from fever in the mechanism that causes the elevated body temperatures: a fever is caused by a change in the body's temperature set-point.
The opposite of hyperthermia is hypothermia, which occurs when an organism's temperature drops below that required for normal metabolism. Hypothermia is caused by prolonged exposure to low temperatures and is also a medical emergency requiring immediate treatment.
Signs and symptoms
Hot, dry skin is a typical sign of hyperthermia. The skin may become red and hot as blood vessels dilate in an attempt to increase heat dissipation, sometimes leading to swollen lips. An inability to cool the body through perspiration causes the skin to feel dry.
Other signs and symptoms vary depending on the cause. The dehydration associated with heat stroke can produce nausea, vomiting, headaches, and low blood pressure. This can lead to fainting or dizziness, especially if the person stands suddenly.
In the case of severe heat stroke, the person may become confused or hostile, and may seem intoxicated. Heart rate and respiration rate will increase (tachycardia and tachypnea) as blood pressure drops and the heart attempts to supply enough oxygen to the body. The decrease in blood pressure can then cause blood vessels to contract, resulting in a pale or bluish skin color in advanced cases of heat stroke. Some victims, especially young children, may have seizures. Eventually, as body organs begin to fail, unconsciousness and coma will result.
Related To :
- CNS Pathology
- Exposure to heat/sun
- Impaired physical environment
- Vigorous activity
Evidenced by :
- Temperature over 37.8 C (100 F) orally, or 38.8 C (101 F) rectally.
- Loss of appetite
- Shivering/goose pimples
- Flushed skin/li>
- Warm to touch
- Increased respiratory rate
Nursing Interventions :
- Administer antipyretics per physician's order.
- Remove excess clothing or blankets.
- Assess possible etiology of increased temperature.
- Encourage fluids when indicated.
- Assess temperature q ___ hours.
- Provide air condition/fan if appropriate.