Pulmonary Function Testing (Quiz 1).txt

  1. What are the general purposes for pulmonary function testing as a component of respiratory care assessment?
    • To identify and quantify changes in pulmonary function.
    • To evaluate and quantify therapeutic effectiveness.
    • Epidemiological surveillance for pulmonary disease.
    • Assessment of postoperative pulmonary risk.
    • To aid in the determination of pulmonary disability.
  2. What factors should a patient have in order to have a Pulmonary Function Test (PFT) performed on them?
    • The diaphragm and thoracic muscles must be capable of expanding the thorax and lungs to produce a subatmospheric pressure.
    • The airways must be unobstructed to allow gas to flow into the lungs and reach the alveoli.
    • The cardiovascular system must circulate blood through the lungs.
    • Oxygen and carbon dioxide must be able to diffuse through the alveolar capillary membrane.
  3. Is PFT used as a sole evaluater of a patient's respiratory system?
    • NO.
    • Other factors include:
    • patient history
    • physical examination
    • chest x-ray
    • arterial blood gas analysis
  4. What are Contraindications for PFT?
    • Hemoptysis
    • Pneumothorax
    • Unstable cardiovascular (e.g., angina, BP problems, recent MI or pulmonary embolus)
    • Thoracic, abdominal, or cerebral aneurysms
    • Recent eye surgery (e.g., cataract)
    • Presence of an acute disease process that might interfere with test (e.g., nausea, vomiting
    • Recent surgery of thorax or abdomen
  5. Four general principles to be considered for PFT test:
    • 1. Specificity - most PF are not specific. Different disease may cause test to be abnormal (limitation). This explains why PFT test identify a pattern of impairment rather than diagnose a specific disease.
    • 2. Sensitivity - some test are extremely sensitive or not sensitive.
    • 3. Validity - each test must be valid to be meaningful. Ensuring pt effort/cooperation, equipment accuracy & calibration.
    • 4. Reliability - consistency of the test. Test must be performed more than once
  6. What are the (3) three components to basic pulmonary function measurements?
    • Lung volumes and capacities
    • Pulmonary (airway) mechanics
    • Diffusion capacity of the lungs (DL)
  7. How do we evaluate Lung Volumes?
    • Tidal volume
    • Inspiratory reserve volume
    • Expiratory reserve volume
    • Residual volume
  8. How do we evaluate Lung Capacities?
    • Total lung capacity
    • Inspiratory capacity
    • Functional residual capacity
    • Vital capacity
  9. What are the four lung volumes?
    • TV = 500 ml, 8-10% of TLC
    • IRV = 3100 ml, 50-55% of TLC
    • ERV = 1200 ml, 20% of TLC
    • RV = 1200 ml, 20% of TLC
  10. What are the four lung capacities
    • IC = TV + IRV, 3600 ml, 60% of TLC
    • VC = TV + IRV + ERV, 4800 ml, 80% of TLC
    • FRC = ERV + RV, 2400 ml, 40%
    • TLC = TV + IRV + ERV + RV, 6000 ml
  11. What does spirometry measure?
    • Tidal volume
    • Inspiratory capacity
    • Inspiratory reserve volume
    • Expiratory reserve volume
    • Vital capacity
  12. What are the indirect measurements of lung volumes and capacities?
    • Residual volume
    • Functional residual capacity
    • Total lung capacity
  13. What do we use to get indirect measurements of lung volumes and capacites?
    • 1. Helium Dilution (closed-rebreathing circuit)
    • 2. Nitrogen Washout (non-rebreathing or open circuit)
    • 3. Body Plethysmography
  14. What is the Significance of Helium Dilution Test?
    • In healthy patients and those with small FRC, equilibrium occurs in 2 to 5 minutes
    • Patient with obstructive lung disease may require up to 20 minutes
    • FRC = (Vol He x FiHe) / FiHe - FfHe / FfHe
  15. What does Nitrogen Washout and Helium Dilution measure?
    FRC, RV & TLC
  16. What is the Significance of Nitrogen Washout Test?
    • Similar to helium dilution, the time it takes to wash out the nitrogen is approx. 2 to 5 minutes in healthy patients
    • longer in those with obstructive lung disease
    • The test must occur in a leak-proof circuit, because the presence of air increases the measured nitrogen percentages and results in grossly elevated measurements of lung volume.
  17. What is the Significance of Body Plethysmography?
    • Changes in lung volumes and capacities are generally consistent with pattern of impairement.
    • TLC, FRC and RV increases in obstructive diseases and decreases with restrictive impairment. For example:
    • TLC is always reduced in restrictive lung disease, unless obstruction and restriction occur together. Then the TLC may be a less sensitive measure of the restrictive impairment.
  18. How does Body Plethysmography work?
    • An electronic controlled shutter near the mouthpiece allows the airway be occluded periodically, thereby measuring airway pressure changes condition of no airflow.
    • pressure changes measured at the mouth are pressure changes in the alveoli
  19. In obstructive diseases, all values except what will be increased?
    VC and IRV
  20. In restrictive diseases, all volumes and capacities and increased or decreased?
  21. What tests are used to determine pulmonary (airway) mechanics?
    • Forced vital capacity (FVC)
    • Forced expiratory volumes (FEV) usually timed
    • Forced inspiratory flow rates (FIF)
    • Forced expiratory flow rates (FEF)
    • Maximum voluntary ventilation (MVV)
  22. What are pulmonary (airway) mechanic tests used to determine?
    • to assess the ability of the lungs to move large volumes of air quickly to identify airway obstruction.
    • Some measurements are to check large airways and others for small airways
  23. For obstructive patients this will be higher or lower than a SVC?
  24. What is Forced Vital Capacity?
    • It is the maximum volume of gas that the patient can exhale as forcefully and as quickly as possible.
    • This test can be done with simple spirometry
  25. What is the most commonly performed test of pulmonary mechanics?
    Forced Vital Capacity
  26. What is Forced Expiratory Volume in one second (FEV1)?
    • It is the maximum volume of gas that the patient can exhale during the first second of a FVC maneuver.
    • This is an extremely useful test to determine between restrictive and obstructive
  27. What is the normal percentage of FVC for FEV1?
    70 to 83% of FVC
  28. FEV3 normal clinical range is __-__% of FVC
  29. What is FEV1/FVC ratio used to determine and what is minimal normal value?
    • compares the forced expiratory volume in 1 sec to its own forced vital capacity
    • FEV1/FVC X 100
    • Minimal value is approximately 70%
  30. What is a Flow Volume Loop?
    It is a Forced Vital Capacity where the graphic relationship between flows and resultant volume during a FVC and subsequent forced inspiratory volume maneuver.
  31. In a Flow Volume Loop, the inspiratory portion is more sensitive to central or peripheral airway obstruction?
  32. In a Flow Volume Loop, the exspiratory portion is more sensitive to central or peripheral airway obstruction?
  33. What is Forced Expiratory Flow 200-1200 (FEF 200-1200)?
    • The average flow rate of exhaled air after the first 200 ml during FVC maneuver
    • It is a measure of the integrity and function of the large airways
  34. What is normal value for FEF 200-1200?
    6 to 7 L/sec (400 L/min)
  35. FEF 200-1200 will be decreased in patients with significant what?
    obstructive lung disease and also those with severe restrictive disease
  36. What is Forced expiratory flow 25%-75% (FEF 25%-75%)?
    • The average flow rate during the middle portion of the FEV
    • It is a measure of the middle 50% of the expiratory flowrate.
  37. FEF 25%-75% is a good measure of small or distal what?
    airway function
  38. What is normal value of FEF 25%-75%?
    4 to 5 L/sec
  39. Is FEF 25%-75% dependent or independent of patient effort?
  40. Will FEF 25%-75% be increased or decreased in patients with obstructive lung disease (it is sensitive to earlier changes)
  41. What is Maximum voluntary ventilation (MVV)?
    • The maximum volume of air moved into and out of the lungs voluntarily 10, 12, or 15 sec.
    • It is an index of the integrity and function of the lung-thorax relationship
  42. What does MVV take into account?
    the airway resistance (obstructive), status of the respiratory muscles (weakness), integrity of the lung parenchyma and thorax (compliance)
  43. What is normal value for MVV?
    150 to 200 L/min. for males
  44. Is MVV patient dependent or independent?
  45. What may MVV exaggerate in obstructive patients?
    air trapping
  46. What is the maximum flowrate that occurs at any point during a forced vital capacity?
    • Peak Expiratory Flow
    • It is usually at the early part of exhalation
  47. Where is Peak Flow (PF) best used and why?
    in home care and for trending to determine increasing bronchospasm
  48. What is normal Peak FLow (PF)?
    400 to 600 L/min (male), 300 to 500 L/min (female)
Card Set
Pulmonary Function Testing (Quiz 1).txt
CRAFTON HILLS COLLEGE RESP 135 Pulmonary Function Testing (Quiz 1)