Pulmonary Function Tests Lecture Powerpoint

Question 1

2 functions of the sinuses and how do we learn to breath first?

Answer 1

• Lighten the weight of the head
• Moisten and filter air

-through the nose

Question 2

Because of the respiratory system’s ability to filter upon inspiration, most pneumonias are the result of…

Answer 2

….reflux and aspiration

Question 3

Further down in the respiratory tract, we see more smooth muscle and less cartilage tissue making it….

Answer 3

…more capable of partial collapse or complete collapse in disease states (this increases residual volume in the lungs as everything distal to the collapse is affected)

Question 4

Functions of PFT’s (3)

Answer 4

• add to diagnosis of disease (pulmonary and cardiac)
• monitor progression of disease and effectiveness of treatment
• aid in pre op assessment of certain patients

Question 5

Different components of PFTs (8)

Answer 5

• spirometry
• flow volume loop
• bronchodilator response
• lung volumes
• diffusion capacity (DLCO)
• bronchoprovocation testing
• max respiratory pressures
• simple and complex cardiopulmonary exercise testing

Question 6

6 min walk test

Answer 6

Test to evaluate physical function or assess therapeutic response in COPD and pulmonary fibrosis patients, considered positive if oxygen saturation falls by >4% ending below 93% after 6 minutes of walking and indicates need for confirmatory ABG’s

Question 7

Indications for PFTs (6)

Answer 7

• Signs and symptoms of pulmonary distress
• screening at risk population (smokers current or former >45 years of age)
• monitoring drug toxicity
• abnormal study such as CXR or EKG
• environmental exposure monitoring
• preoperative assessment and risk stratification

Question 8

PFT’s are beneficial but…

Answer 8

….they only support or exclude a diagnosis

Question 9

Steps to performance of an FVC maneuver in spirometry

Answer 9

• Prep patient (results are VERY effort dependent)
• cover nose with clip
• elevate chin slightly and extend neck slightly
• put mouthpiece in mouth after inhaling and then exhale hard and fast as possible
• need to avoid coughing, variable flow, or early termination

Question 10

Spirometry’s goal is to measure ____, it cannot (directly) measure ____

Answer 10

Vital capacity, residual volume

Question 11

Body plethysmography

Answer 11

Used to measure total lung capacity by placing patient in a small airtight room while taking measurements to determine residual volume and total lung capacity

Question 12

Flow (flow volume loop) definition

Answer 12

Volume of a substance moved thru a structure or space over a period of time in L/s

Question 13

Flow volume loop, what is it sometimes referred to as?

Answer 13

• A measurement of flow during pulmonary function testing that should have a rounded inhalation and a sharp spike in expiration (this height should represent 90% of what can be exhaled) followed by continuous drop straight line
• also referred to as a spirogram

Question 14

Volume time loop

Answer 14

A measurement of flow during pulmonary function testing that determines FEV1 and should have 90% of the volume (in L) released in the first second before quickly tapering off to a flat line

Question 15

Lung properties that affect spirometry (2)

Answer 15

• mechanical properties (compliance and elastic recoil)

- resistive properties (affected by airway diameter predominantly)

Question 16

% predicted in spirometry

Answer 16

What a patient performed based on what is predicted based on age, gender, height, weight, ethnicity to determine some fraction value which is then interpreted (low % is worse for the patient)

Question 17

Spirometry % FVC predicted value interpretation

Answer 17

80-120% normal
70-79% mild reduction
50-69% moderate reduction
<50% severe reduction

Question 18

Spirometry % FEV1 predicted value interpretation

Answer 18

> 75% normal
60-75% mild obstruction
50-59% moderate obstruction
<49% severe

Question 19

Spirometry % FEF 25-75% predicted value interpretation

Answer 19

> 60% normal
40-60% mild
20-40% moderate
<10% severe

Question 20

Obstructive disease pattern loss with spirometry % predicted values

Answer 20

• FEF 25-75 decreased
• FEV1 decreased
• FVC normal to decreased in late stage (last thing to go)
• FEV1/FVC <70% predicted

Question 21

Obstructive lung disease list (5)

Answer 21

• asthma (reversible obstructive dz)
• COPD (chronic bronchitis and emphysema)
• bronchiectasis
• bronchiolitis
• upper airway obstruction

Question 22

Restrictive disease pattern loss with spirometry % predicted values

Answer 22

• TLC decreased
• FVC decreased
• Normal or increased FEV1/FVC ratio

Question 23

Restrictive lung disease list (4)

Answer 23

• Parenchymal disease (interstitial lung disease)
• pleural disease
• chest wall disease
• neuromuscular disease

Question 24

Scooped out vs witch’s hat on volume/flow diagram

Answer 24

Scooped out is characteristic of obstructive disease, witch’s hat is characteristic of restrictive disease

Question 25

Bronchodilator response spirometry

Answer 25

Test done on patients with obstructive pattern on spirometry to determine degree to which FEV1 improves with inhaled bronchodilator to document reversible airflow obstruction, significant if FEV1 increases by 12% and 200mL or greater

Question 26

Fixed upper airway obstruction pattern on flow volume loop (such as a tumor in larynx) vs variable extrathoracic obstruction vs variable intrathoracic obstruction

Answer 26

- Rounded shape with equal expiratory (+) and inspiratory (-) values - Rounded shape with greater expiratory (+) and lower inspiratory (-) flow - Rounded shape with lower expiratory (+) and greater inspiratory (-) flow

Question 27

- Methods for measuring lung volumes (3) | - Indications for a lung volume measurement (2)

Answer 27

- Helium, nitrogen washout, body plethsmography | - diagnose restrictive component, differentiate between chronic bronchitis from emphysema

Question 28

Lung volume % predicted patterns (TLC and RV) in obstructive and restrictive disease

Answer 28

Obstructive: TLC>120% predicted, RV >120% predicted Restrictive: TLC <80% predicted, RV <80% predicted

Question 29

Carbon monoxide diffusion capacity (DLCO), what does a decreased and increased value mean?

Answer 29

- Measures the lungs diffusing capacity to transport inhaled gas from alveoli to pulmonary capillaries using a small amount of carbon monoxide - <80% predicted indicates obstructive lung disease or anemia, >120% predicted indicates asthma or polycythemia

Question 30

7 barriers to o2 transport in the alveoli according to walt

Answer 30

- alveolar epithelium - tissue interstitum - capillary epithelium - plasma layer - red cell membrane - red cell cytoplasm - hemoglobin binding forces and type of hemoglobin

Question 31

Bronchoprovocation testing, what is a positive result?

Answer 31

Use of methacholine, histamine, or exercise stress test in an attempt to induce bronchospasm useful in diagnosis of asthma and diagnostic if >20% decrease in FEV1

Question 32

Obstructive pattern evaluation of FVC. FEV1, FEV1/FVC, FV loop shape, DLCO, TLC/RV, responsiveness to bronchodilator

Answer 32

- FVC normal or decreased - FEV1 decreased - FEV1/FVC decreased <70% - scooped loop - DLCO decreased in emphysema or normal in crhonic bronchitis - TLC/RV increased - positive response to bronchodilator

Question 33

Restrictive pattern evaluation of FVC, FEV1, FEV1/FVC, FV loop shape, DLCO, TLC/RV

Answer 33

- FVC decreased - FEV1 decreased or normal - FEV1/FVC normal - witch's hat loop - DLCO decreased - TLC/RV decreased

Question 34

DLCO will be ___ in emphysema but ___ in chronic bronchitis because ____

Answer 34

Decreased, normal, chronic bronchitis affects proximal airways where gas exchange is not taking place

Question 35

Acinus

Answer 35

The anatomic unit of the lung supplied by the terminal bronchiole where gas exchange in the respiratory system occurs

Question 36

Principle of child lung function preservation

Answer 36

Need to preserve while young so it continues to have sufficient reserve when old

Question 37

The 4 volumes of the lung

Answer 37

- Inspiratory reserve - tidal - expiratory reserve - residual

Question 38

The 4 capacities of the lung

Answer 38

(2 or more volumes comprise a capacity) - vital - inspiratory - functional residual - total lung

Question 39

FEV1

Answer 39

Forced expiratory volume in 1 second, a very beneficial measurement taken by spirometry

Question 40

FVC

Answer 40

Forced vital capacity, a very beneficial measurement taken by spirometry

Question 41

FEV1/FVC%

Answer 41

The forced expiratory volume in one second divided by the total forced vital capacity, should be 90% in a healthy lung, a very beneficial measurement taken by spirometry

Question 42

FEF25-75

Answer 42

Measure of forced expiratory flow during middle have of FVC, provides insight into the smaller and intermediate airways and indicates treatment being necessary as early stages of lung disease progresses before other spirometric values are decreased as well

Question 43

____ spirometry measurement is used to track severity of COPD over time

Answer 43

FEV1

Question 44

Normal lungs have ___ flow rate and ___ lung volume Restrictive lungs have ___ flow rate and ___ lung volume Obstructive lungs have ___ flow rate and ___ lung volume

Answer 44

- High, high - High, low - Low, high

Question 45

Bronchoprovocation is useful in diagnosis of asthma in the setting of ____ PFTs

Answer 45

Normal