Fever

Fever or Pyrexia is the temporary increase in the body's temperature in response to a disease or illness.

The elevation of an individual's core body temperature is often due to a physiological process brought about by infectious causes or non-infectious causes such as autoimmune processes, malignancy, or inflammation. These processes involve the release of immunological mediators, which trigger the thermoregulatory center of the hypothalamus to raise the body's core temperature.

Fever is sometimes called Hyperthermia although this is a misnomer. Fever and Hyperthermia are different. In fever, there is an increase in the "set-point" temperature brought about by the hypothalamus, enabling the body to maintain a controlled increase in the core temperature and general functionality of all organ systems while in hyperthermia, the rise in the body's temperature is beyond the boundary of the set-point temperature and regulation of the hypothalamus.

Other Names for fever

Elevated temperature, Hyperthermia, Pyrexia, Febrile, Hyperpyrexia

Signs

In children:

100.4°F (38°C) measured in the bottom (rectally)
99.5°F (37.5°C) measured in the mouth (orally)
99°F (37.2°C) measured under the arm (axillary)

In adults:

99°F to 99.5°F (37.2°C to 37.5°C), depending on the time of day.

Types

Doctors have classified five main types of fever including:

Intermittent fever: This type has a fluctuating baseline between normal temperatures and fever levels over the course of the day.
Remittent fever: This type may come and go, and the temperature fluctuates, and although it falls, it never falls all the way back to normal.
Hectic fever: Either an intermittent or a remittent fever is considered hectic if the temperature range swings widely throughout the day, with a difference of at least 1.4 degrees Celsius (34.52° F) between the highest and lowest temperatures.
Continuous fever or sustained fever: This is a prolonged fever with little or no change in temperature over the course of a day.
Relapsing: This is a type of intermittent fever that spikes up again after days or weeks of normal temperatures. This type is common with animal bites and diseases like malaria.

Other Signs

A fever is not an illness but a symptom or sign of an illness or infection in your body. However, a fever is commonly accompanied by other symptoms including:

Sweats or chills
Headache
Achy muscles
Rash
Restlessness
Lack of appetite
Weakness or fatigue
Hot, flushed skin
Increased heart rate
Increased respiratory rate
Seizures

Diagnosis

The best way to diagnose pyrexia is to take a temperature with a thermometer.

Nursing Interventions

Assess for signs of fever
Assess for signs of dehydration
Monitor the patient's heart rate and blood pressure
Identify the triggering factors for pyrexia and review the client's history, diagnosis, or procedures
Determine age and weight
Accurately measure and document the client's temperature every hour or as frequently as indicated, or when there is a change in the client's condition
Monitor fluid intake and urine output
Recognize the signs and symptoms of heat exhaustion or heat-related illness
Recognize the signs and symptoms of heatstroke
Loosen or remove excess clothing and covers
Provide hypothermia blankets or cooling blankets when necessary
Provide a tepid bath or sponge bath
Apply ice packs to the patient
Monitor the skin during the cooling process
Adjust and monitor environmental factors like room temperature and bed linens as indicated
Monitor cooling measures based on the patient's physical response
Monitor the patient for shivering
Raise the side rails and lower the bed at all times
Provide nutritional support as indicated
Keep clothing and bed linens dry
Encourage adequate fluid intake

Treatment

Most fevers will resolve on their own in a few days. Here are some remedies to help relieve a fever:

Rest
Drinking plenty of fluids, such as water, to avoid dehydration
Eating light foods that are easy to digest
Dressing in light clothing

Pyrexia can be treated with paracetamol, acetaminophen, or ibuprofen. Switching between giving acetaminophen and ibuprofen can cause medicine errors and may lead to side effects. But it sometimes works better than using only one or the other. Aspirin shouldn't be given to a child or young adult who has a fever. Aspirin can cause an upset stomach and intestinal bleeding. It may also cause Reye syndrome.

A lukewarm bath may reduce the fever. Alcohol rubdowns are no longer recommended as it can lower the body temperature too quickly.