Fever
Fever or pyrexia in humans is a symptom of an anti-infection defense mechanism that manifests itself when the body temperature surpasses the normal range due to a rise in the set point of the hypothalamus’s temperature. There is no generally accepted upper limit for normal temperature sources using values ranging between 37.2 and 38.3 °C in humans. Set point is increased with an increase in muscular contraction causing one to feel cold or to have chills.
Thus, this increases the rate of production of heat and attempts made to preserve it. As the set point temperature returns to normal, a person has feelings of hotness, appears red with a flushed appearance, and also becomes sweaty. Seldom fever may trigger a febrile seizure with its manifestation occurring frequently in children. Fevers rarely rise above 41 to 42 °C. A fever can be the result of many medical conditions that range from benign to life-threatening. These include viral, bacterial, and parasitic infections such as influenza, common cold, meningitis, urinary tract infections, appendicitis, Lassa fever, COVID-19, and malaria. Other symptoms are infectious vasculitis deep vein thrombosis connective tissue disease side effects of medication or vaccination and cancer.
Kinds of fever
There are various patterns of observed measured patient temperatures, and some of these might be an indication of a certain type of medical diagnosis
Continuous fever is when the temperature remains above normal and will not fluctuate more than 1°C in 24 hours in bacterial pneumonia, typhoid fever, infective endocarditis, tuberculosis, or typhus.
Intermittent fever is only for a period as it will later cycle back to normal in malaria, leishmaniasis, pyemia, sepsis, African trypanosomiasis.
Remittent fever where the temperature remains above normal throughout the day and fluctuates more than 1 °C in 24 hours in infective endocarditis. Undulant fever is seen in brucellosis.
Typhoid fever is a continuous fever showing a step-ladder pattern, a step-wise increase in temperature with a high plateau.
Among the varieties of paroxysmal fever are those particular to malaria cases caused by various pathogens. These include Furthermore, there is controversy over whether a particular fever pattern is related to Hodgkin’s lymphoma Pel Ebstein fever, in which patients are said to have a high temperature for one week, low for the next week, and so on, in which the general applicability of this pattern is disputed.
Hyperpyrexia fever
Hyperpyrexia is the extreme elevation of the body temperature, depending on the source, being classified as having a core body temperature equal to or greater than 40 or 41 °C. Hyperpyrexia cases included range from what is termed as severe (≥ 40 °C) to extreme. The concept differs from hyperthermia where one’s thermoregulatory system has the set point of body temperature set above the norm and then generates heat for it to happen.
In contrast, the body temperature rises above the set point due to some other factors in hyperthermia. It is considered a medical emergency because of hyperpyrexia’s high temperature, which may indicate a serious underlying condition and lead to severe morbidity including permanent brain damage or death. The most common cause of hyperpyrexia is intracranial hemorrhage. Other causes in emergency room settings include sepsis, Kawasaki syndrome, neuroleptic malignant syndrome, drug overdose, serotonin syndrome, and thyroid storm.
Care of fever
Fever is not required to be treated and most individuals with fever recover without any special medical care. Though it is unpleasant, fever hardly becomes dangerous if it remains untreated. Damage to the brain typically does not occur until temperatures reach 42.0 °C and an untreated fever rarely exceeds 40.6 °C. Treatment of fever in patients with sepsis does not alter outcomes. Small trials have found no benefit to treating fevers of 38.5 °C or greater in critically ill patients in ICUs, and one trial was stopped early because patients who were treated more aggressively to lower their fever were dying more frequently.
The two assumptions that are generally used to argue in favor of treating fevers have not been experimentally validated by the NIH. These are that a fever is harmful, and suppression of a fever will decrease its harmful effect. Most of the other studies that support the association of fever with worse outcomes have been observational. In theory, these critically ill patients and those subjected to additional physiologic stress may benefit from fever reduction, but the evidence on both sides of the argument appears to be mostly equivocal.
Conservative measures for fever
Evidence does little to support sponging or bathing feverish children with tepid water, but the use of a fan or air conditioning reduces fever and increases comfort with each degree of temperature decline. If the temperature reaches an extremely high level hyperpyrexia, aggressive cooling is required generally produced mechanically via conduction by applying numerous ice packs across most of the body or direct submersion in ice water. Generally, people should drink enough fluids. It is not known whether higher fluid intake enhances symptoms or reduces the duration of respiratory illnesses like the common cold.
Medications for fever
fever is an effective treatment of fever in children. It is more potent than acetaminophen paracetamol in children. Ibuprofen and acetaminophen can be given safely together to children who have fever. Its efficacy alone has been questioned in children who have fevers. Ibuprofen is also more effective than aspirin in children who have fevers. It also must not be used on children and young adults younger than 16 or 19 years of age, depending upon the country, because it may precipitate Reye’s syndrome.
More effective at suppressing fever is the combination of both the two drugs, paracetamol and ibuprofen on the same day or swinging the two as compared to either paracetamol or ibuprofen in combination. It is still vague whether it improves comfort for a child.
Until 2019, studies on the effect of antipyretics on the mortality risk in infected patients had yielded mixed results.