Vital Signs: Monitoring and Evaluating the Body's Physiological Status

1. Chapter 8 Vital Signs

2. T--temperature P--pulse Vital Signs R--respiration Bp--blood pressure

3. vital signs • reflect the body’s physiological status • present condition • provide information to evaluate homeostatic balance in status • be a quick and efficient way • to monitor a patient’s condition • to identify problems • to evaluate the patient’s response to intervention

4. vital signs • Vital signs and other physiological measurements are the basis for clinical problem solving. • An alteration in vital signs may signal the need for medical or nursing intervention. --Vital signs should be taken at regular intervals. --As nurses we should know the relevant knowledge about vital signs be able to measure vital signs accurately interpret their significance make decisions about interventions

5. SectionⅠGuidelines for Taking Vital Signs 1. select equipment : • be functional and appropriate • based on the patient’s condition and characteristics 2. know the patient’s normal range of vital signs---serve as a baseline for comparison with findings taken later 3. know the patient’s medical history, therapies, and prescribed medications • Some illnesses or treatments cause predictable vital sign changes. • Most medications affect at least one of the vital signs.

6. SectionⅠGuidelines for Taking Vital Signs 4. control or minimize environmental factors may affect vital signs 5. use an organized, systematic approach when taking vital signs ---each procedure requires following a step-by-step approach to ensure accuracy 6. the frequency of vital signs assessment --based on the physician and the patient’s condition

7. SectionⅠGuidelines for Taking Vital Signs 7. use vital sign assessment to determine indications for medication administration ----cardiac drugs 8. analyze the results of vital sign measurement--not interpret them in isolation 9. verify and communicate significant changes in vital signs

8. SectionⅡ Body Temperature • Physiology of Body Temperature • Factors Affecting Body Temperature • Alterations in Body Temperature • Nursing Process and Thermoregulation

9. Physiology of Body Temperature • Definition of body temperature • Heat production and heat loss • Regulation of body temperature • Average temperature and normal range of adult

10. Definition of body temperature Body temperature is the heat of the body.-- reflects the balance between the amount of heat produced by body processes the amount of heat lost to the external environment

11. Definition of body temperature • core temperature : temperature of deep tissues (cranium, thorax, abdominal and pelvic cavity ), relatively constant • Surface temperature :the temperature of the skin, the subcutaneous and the fat tissue , fluctuates from 36℃ to 38℃

12. Heat Production • Heat is produced in the body through metabolism. • The main heat production organs of the body are liver and skeletal muscles. • Heat production occurs duringrest, voluntary movements, involuntary shivering, and nonshivering thermogenesis(brown adipose).

13. Heat Loss Heat is lost through physical mode. The main heat loss part of the body is skin.(70%) (R29%,elimination1%) • Radiation • Conduction • Convection • Evaporation

14. Radiation • Radiation is the transfer of heat between two objects without direct contact by electromagnetic waves. • Heat radiates from the skin to any surrounding cooler object. • increase T difference between two objects • Increase radiating surface area heat loss • Increase the extent of vasodilation

15. Conduction • Conduction is the transfer of heat from one object to another with direct contact. • When the warm skin touches a cooler object(solid; gas; liquid), heat is lost. • Heat loss velocity depends on • Heat conducting capability • T difference between the two objects • Contacting area

16. Convection • Convection is the transfer of heat away by air or liquid movement. • Heat is first transferred to air or liquid molecules directly in contact with the skin. Air or liquid currents carry away the warmed air or liquid. • Heat loss velocity depends on • current velocity • T difference between the object and air or liquid

17. Evaporation • Evaporation is the transfer of heat energy when a liquid is changed to a gas. • The body continuously loses heat by evaporation. --R;skin 300-400ml/d • By regulating sweating, the body promotes additional evaporative heat loss. --febricide • Evaporation is the main heat loss mode when environment temperature is higher than body temperature.

18. Regulation of Body Temperature • Neural and Vascular Control • Behavioral Control

19. Neural and Vascular Control • T regulation center :the hypothalamus , controls body temperature the same way a thermostat works in the home (reflex arc) • the anterior hypothalamus controls heat loss Via sweating, vasodilation, inhibition of heat production • the posterior hypothalamus controls heat production via muscle shivering , heat conservation by vasoconstriction of surface blood vessels

20. Normal Blood Temperature (37℃ ) Factors which increase metabolic rate or Environmental temperature Increased blood temperature above level at which “thermostat” in hypothalamus is set (37℃ ) (to or toward) Decreased blood temperature Stimulated thermal receptors Of heat-dissipating center in hypothalamus, initiating impulses that lead to Increased heat Loss by evaporation Increased sweat secretion Increased heat Loss by radiation Dilation of skin blood vessels Heat loss mechanisms to maintain normal body temperature

21. Behavioral Control • environmental temperature fall: add clothing move to a warmer place raise the thermostat setting increase muscular activity by running sit with arms and legs tightly wrapped together

22. Behavioral Control • The ability of a person to control body temperature depends on • the degree of temperature extreme • the person’s ability to sense feeling comfortable or uncomfortable--infants, older adults • thought processes or emotions--depression • the person’s ability to remove or add clothes —infants, children

23. Average Temperature and Normal Range of Adult site average temperature normal range oral 37℃ 36.3-37.2℃ rectal 37.5℃ 36.5-37.7℃ axillary 36.5℃ 36.0-37.0℃

24. Factors Affecting Body Temperature • Measurement site • Circadian rhythms : drops between 2 and 6 AM peaks between 1 and 6PM • Age:With age,T tends to fall . infancy: temperature regulation is labile aging: control mechanisms deteriorate

25. Factors Affecting Body Temperature • Hormonal influences : progesterone: raise the body temperature • Exercise :increase body temperature • Medications: anaesthetic: depress T regulation center promote vasodilation febrifuge: T T

26. Factors Affecting Body Temperature • Stress:Stimulate sympathetic nervous system -- epinephrine and norepinephrine production , -- metabolic activity heat production --T • Environment:the extent of exposure, air temperature and humidity the presence of convection currents • Ingestion of hot/cold liquids • Smoking:increase body temperature

27. Alterations in Body Temperature • Fever or Hyperthermia • Hypothermia

28. Fever or Hyperthermia • A body temperature above the usual range is called fever. • A true fever results from an alteration in the hypothalamic set point. • Pyrogens such as bacteria and virus cause a rise in body temperature. • Fever is an important defense mechanism.

29. Fever process and manifestation • Fever-chill phase:heat production>heat loss; experience tiredness, paleness, dryness, chills, shivers, and feels cold(2 patterns) • plateau phase :heat production=heat loss; warm , dry, R , P , headache, faint, inappetence • fever break phase:heat production<heat loss; skin -- warm, flushed, diaphoresis (2 patterns)

30. Hyperthermia (clinical) • An elevated body temperature related to the body’s inability to promote heat loss or reduce heat production is hyperthermia. • Any disease or trauma to the hypothalamus can impair heat loss mechanisms.

31. Classification of Fever (Oral) ℃℉ Mild 37.5℃-37.9℃ 99.5℉-100.2℉ Moderate 38.0℃-38.9℃ 100.4℉-102.0℉ Severe 39.0℃-39.9℃ 102.2℉-105.6℉ Profound >41℃ >105.8℉

32. Patterns of Fever • is the modality of a temperature curve. • differ depending on the causative pyrogen. • The increase or decrease in the amount of pyrogens results in fever spikes and declines at different times of the day. • The duration and degree of fever depends on the pyrogen’s strength and the ability of the individual to responds. ----serve a diagnostic purpose.

33. Patterns of Fever • Constant Fever • Remittent Fever • Intermittent fever • Irregular Fever

34. Constant Fever • sustains between 39~40℃ • demonstrates little fluctuation of less than 1℃ within 24 hours. ( pneumonia , typhoid)

35. Remittent Fever • has great fluctuation above the normal with more than 1℃ in 24 hours and cannot return to normal temperature level. (septicemia , rheumatic fever)

36. Intermittent fever • fluctuates greatly in 24 hours, may suddenly rise above the normal then suddenly fall to or below the normal • alternates regularly between a period of fever and a period of normal temperature levels (malaria, tuberculosis)

37. Irregular Fever • irregularity alternates between a period of fever and a period of normal temperature values. ( influenza , cancer)

38. Hypothermia • A body temperature below the lower limit of normal 35℃ is called hypothermia． • Heat loss during prolonged exposure to cold overwhelms the body’s ability to produce heat，causing hypothermia． • Hypothermia may be intentionally induced during surgical procedures to reduce metabolic demand and the body’s need for oxygen．

39. Classification of Hypothermia ℃℉ Mild 33.1℃-36℃ 91.5℉-96.8℉ Moderate 30.0℃-33℃ 86.1℉-91.4℉ Severe 27℃-30℃ 80.6℉-86.0℉ Profound <27℃ <80.6℉

40. Manifestation of Hypothermia • 34.4-35℃:uncontrolled shivering，loss of memory，depression, poor judgment • falls below 34.4℃ heart and respiratory rates blood pressure fall skin ---- cyanotic • progress---cardiac dysrhythmias， loss of consciousness， unresponsive to painful stimuli

41. Nursing Process and Thermoregulation • Assessment • Nursing Diagnosis • Planning • Implementation • Intervention

42. Assessment • Sites:mouth，rectum, axillary tympanic membrane • Thermometers Glass Thermometer Electronic Thermometer Disposable Thermometer

43. Glass Thermometer VCD

44. Electronic Thermometer

45. Disposable Thermometer

46. Nursing Diagnosis Nursing diagnosis Diagnosticfoundation Hyperthermia Increase body temperature above usual range Flushed skin, skin warm to touch Increased pulse and respiratory rate Herpetic lesions of the mouth Hypothermia Decreased body temperature Pale, cool skin Decreased pulse and respiratory rate Feelings of cold and chill Ineffective Older adults or infants, weak inability to adapt thermoregulation to environmental temperature

47. Planning • require an individualized care plan -- maintaining normothermia and reducing risk factors． • education is important • Objects:restoring normothermia minimizing complications promoting comfort • care plan should support goals

48. Examples for goals and outcomes • Goal Restore and maintain normothermia. • Outcome Temperature maintained within normal range during environment changes.

49. Examples for goals and outcomes • Goal Minimize complications of altered body temperature. • Outcomes patient’s blood pressure, pulse, and respirations are within normal limits patient’s skin integrity maintained patient’s nutritional intake meets body needs patient’s mucous membranes are moist patient is able to participate in ADL activities patient’s skin is warm and pink patient reports sense of rest and comfort

50. Examples for goals and outcomes • Goal Reduce risk of altered body temperature. • Outcomes patient identifies risk factors for altered body temperature patient practices measures to prevent body temperature alteration