Fever

Fever is an elevation of body temperature that exceeds
normally daily variation and occurs in conjunction with an
increase in the hypothalamic set point for e.g. 37⁰C-
39⁰C.

1. FEVER SOLOMON M KAYASA

2. Introduction A fever is a body temperature that’s higher than is considered normal. It’s also called a high temperature, hyperthermia, or pyrexia, and it’s usually a sign that your body is working to keep you healthy from an infection.

3. introduction Temperature control mechanisms of human beings keep the body’s core temperature relatively constant despite extremes in environmental conditions and physical

4. The normal body temperature ranges from 36.5 to 37.5 ℃ maintained by the hypothalamic regulatory centre . During a 24 hour period, temperature varies from lowest levels in the early morning to highest in the late afternoon.

5. General objective At the end of the lesson, students should be able to demonstrate an understanding on the management of patients with fever.

6. Specific objectives At the end of the lesson students should be able to:  Define fever Mention the causes of fever Describe the patterns of fever State the signs and symptoms of fever Outline the management of fever.

7. Definition of terms Body temperature is the degree of hotness or coldness of a body. It is the somatic sensation of heat or cold. It is the degree of or intensity of heat of a body in relation to external environment.

8. thermoregulation The body temperature is the difference between the amount of heat produced by body processes & the amount of heat lost to the external environment. Body Temperature = Thermogenesis–Heat Loss

9. Definition of terms cont’d… Core temperature: it is the temperature of internal body tissues below the skin & subcutaneous tissues. The sites of measurement are rectum, tympanic membrane, esophagus , pulmonary artery & urinary bladder.

10. Homeostasis is the ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes. Hyperpyrexia is a high fever, usually above 41ºC ( 105.8ºF ).

11. Surface body temperature- it refers to the body temperature of external body tissues at the surface that is of the skin & subcutaneous tissues.

12. fever Fever (pyrexia) is an increase above normal (considered to be 37ºC or 98.6ºF) in body temperature . A person with a fever is said to be febrile and with a fever is said to be afebrile . Pyrogen -a substance, typically produced by a bacterium, which produces fever when introduced or released into the blood.

13. Physiology of thermoregulation The body maintains the body temperature through metabolic processes in the body e.g homeostasis. In humans, temperature homeostasis is controlled by the thermoregulatory center in the hypothalamus.

14. Physiology of thermoregulation The hypothalamus receives inputs from two sets of thermoreceptors : receptors in the hypothalamus monitor the temperature of the blood. receptors in the skin monitors the external temperature.

15. Physiology of thermoregulation The thermoregulatory centre sends impulses to several different effectors to adjust body temperature. When the message has reached the hypothalamus, a series of reactions follow.

16. Factors Affecting Body Temperature A variety of factors affect body temperature. These factors include circadian rhythms, age, gender, stress, and environmental temperatures .

17. gender Women tend to experience more fluctuations in body temperature than do men, probably the result of changes in hormones . The increase in progesterone secretion at ovulation increases body temperature as much as 0.3º to 0.6ºC (0.5º to 1 º F ).

18. Circadian rhythms Are 24-hour cycles that are part of the body's internal clock, running in the background to carry out essential functions and processes. For instance, body temperature is usually about 0.6ºC ( 1º to 2 º F ) lower in the early morning than in the late afternoon and early evening.

19. Age Older adults lose some thermoregulatory control with aging and are at risk for harm from extremes of temperature. The body temperature of infants and children changes more rapidly in response to both hot and cold air temperatures.

20. Environmental Temperature Most of us respond to changes in environmental temperature by wearing clothing that either allows increased heat loss when it is hot or retains heat when it is cold.

21. stress Psychological stress can trigger physiological responses, including an increase in body temperature. A neural circuit that underlies this stress-induced heat response has been identified.

22. Exercise Hard work or strenuous exercise can increase body temperature to as high as 38.3 ⁰C to 40 ⁰C.

23. Mechanism of heat loss

24. fever Fever also known as pyrexia is defined as an elevation of body temperature of above 37.5 ℃ mediated by an increase of the hypothalamic heat regulatory set-point (Potter & Perry 2009).

25. Common medical sign characterized by an elevation of temperature above the normal range of 36.5 -37.5oC due to an increase in the body temperature regulatory set point ( Karakitsos and Karabinis , 2008).

26. Loss of

27. What causes fever? The cause of fever may be infectious or non-infectious

28. Infectious Pyrogens are substances that cause fever eg fungi, viruses, and bacteria. Pyrogens causes fever by inducing release of endogenous pyrogens (IL-1, Tumor necrosis factor, Interferon-y and IL-6) produced by the host cells that elevates the hypothalamic set point.

29. Non-infectious Non-infectious causes include Inflammation caused by trauma Neoplastics Environmental Drug-mediated Immunological causes

30. Types of fever Continuous fever : Temperature remains above normal throughout the day and does not fluctuate more than 1 °C in 24 hours, e.g. lobar pneumonia, typhoid, meningitis, urinary tract infection, brucellosis, or typhus.

31. Intermittent fever : The temperature elevation is present only for a certain period, later cycling back to normal , e.g. malaria, kala-azar, pyaemia , or septicemia.

32. Remittent fever : Temperature remains above normal throughout the day and fluctuates more than 1 °C in 24 hours , e.g., infective endocarditis .

33. Pel-Ebstein fever : A specific kind of fever associated with Hodgkin's lymphoma, being high for one week and low for the next week and so on. However , there is some debate as to whether this pattern truly exists.

34. A neutropenic fever : also called febrile neutropenia, is a fever in the absence of normal immune system function . Because of the lack of infection-fighting neutrophils, a bacterial infection can spread rapidly; this fever is, therefore, usually considered to require urgent medical attention.

35. Neurogenic fever is the result of damage to the hypothalamus from pathologies such as intracranial trauma, intracranial bleeding, or increased intracranial pressure. This type of fever does not respond to antipyretic medications ( Porth & Matfin , 2009).

36. Fever of unknown origin (FUO) also known as pyrexia of unknown origin(PUO) is body temperature ≥ 38.3° C (101° F) that lasts 3 weeks or longer and does not result from transient and self-limited illness, rapidly fatal illness, or disorders with clear-cut localizing symptoms or signs or with abnormalities on common tests such as chest x-ray, urinalysis, or blood cultures.

37. This kind of fever is more commonly seen in people receiving immune-suppressing chemotherapy than in apparently healthy people.

38. Febricula is an old term for a low-grade fever, especially if the cause is unknown, no other symptoms are present , and the patient recovers fully in less than a week.

39. Grades of fever Low grade fever: 37.5º-38.2ºC(98.8-100.6Fº ) High grade fever: 38.2º-40.5ºC(100.6-104.9ºF) Hyperpyrexia : >40.5ºC(104.9ºF)

40. Classification according to period Acute fever ; type of fever which takes less than 7 days. It is characteristic of infectious diseases such as malaria and viral related upper respiratory tract infections.

41. Classification according to period Sub-acute fever ; type of fever that take less than 2 weeks in duration. This type of fever may be seen in cases of typhoid fever and intra-abdominal abscess.

42. Classification according to period Chronic Fever ; type of fever which takes more than 2 weeks. Is typical of chronic bacterial and viral infections e.g T.B, HIV and cancer.

43. Management of fever

44. NURSING DIAGNOSIS

45. Lets take a break

46. hypothermia Is a condition in which an organism's temperature drops below that required for normal metabolism and bodily functions.

47. ASSIGNMENT What are the differences between fever and hyperthermia ? Go and read on the management of hypothemia

48. REFERENCES Axelrod & Diringer (2008). Temperature management in acute neurologic disorders. Neurol. Clin . 26 (2): 585-603. Karakitsos & Karabinis (2008). Hypothermia therapy after traumatic brain injury in children. N. Engl. J. Med. 359(11): 1179-80. Lewis. S., Hertkemper , M., M, Dirksen, S., R., O’Brien, P., G., Bucher, L., (2007). Medical - Surgical Nursing -Assessment and Management of clinical problems.7th edition. Mosby. St Louis. Missouri. USA. Monahan, F., Sands J.K., Neighbors M., Marek, J.,F and Green C. (2007). Phipp’s Medical –Surgical Nursing: Health and illness perspectives. 8th edition. Mosby, Elsevier, USA. Oats, J., and Abraham, S., (2008). Fundamentals of Obstetrics and Gynecology , 8th edition, Elsevier, Edinburgh. Perry A. G. and Potter P. A. (2009), Fundamentals of Nursing, 7th edition, Mosby, Elsevier Smeltzer , S., C., Bare, B., G., (1999). Brunner and Suddarths ’ textbook of Medical - Surgical Nursing. 9THEdition. Lippincott. Philadelphia.