Pulmonary Function Tests Flashcards
Exhaled breath nitric oxide is a useful measure of…
eosinophilic airway inflammation in asthma
In what condition would the following changes occur in spirometry?
a. decrease FVC
b. decrease FEV1
c. increase RV
COPD
Methacholine/Histamine/Mannitol are examples of…
an indirect inflammatory challenge
markers of airway hyper-responsiveness with a concentration to cause a decrease of 20% FEV1
In what conditions would the RV increase?
FVC reduction
what levels of exhaled Nitric oxide reflect uncontrolled asthmatic inflammation?
>35ppb
The total lung capacity is decreased in emphysema - true or false?
false
emphysema causes difficulting in getting air out and thus results in hyperinflation and an increased TLC
Examples of effort dependent tests (2)
How are they carried out?
FEV
Flow rates
Carried out using spirometry
A change in which value will occur in asthma?
FVC
FEV1
Residual Volume
FEV1
The FVC will remain the same as the total capacity is possible but takes longer. The residual volume remains the same unless there is chronic poor-control and thus airway remodelling
When spirometry is normal, FEV1/FVC should be <75% - true or false?
False
They should be greater than 75%.
Asthmatics may also produce this if they have good lung volume, good control and have been involved in activities that focus on diaphragmatic breathing
What changes in the following parameters in spirometry would be expected in a patient with COPD
a. FVC
b. FEV1
c. Residual Volume
a. there should be a decrease in FVC
b. There would be a decrease in FEV1
c. The residual volume would increase
Forced Expiratory Ratio
FEV1/FVC
What are the expected values of…
PEFR
FEV1
FVC
FEV1/FVC Ratio
FEV1 repsonse to ß2 agonists
…in obstructive disease?
PEFR - decreased
FEV1 - decreased
FVC - Normal in Asthma
Decreased in COPD
FEV1/FVC ratio - <75%
Response to b2 agonist - >15% asthma
<15% in COPD
Why does the FEV1 initially go up in exercise?
Due to the release of adrenaline.
Asthmatics then get bronchoconstriction as there is a rebound reaction
Describe Total Lung Transfer for CO
CO diffusion across alveolar-capillary barrier - aka single breath diffusing capacity
Acts as a soluble gas marker with a high binding affinity for haemoglobin
It is corrected for Alveolar Volume (KCO)
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What is total lung transfer for CO corrected for?
Alveolar Volume
What are the most common types of pulmonary function tests?
Effort dependent tests
Which condition exhibits pressure dependent expiratory airway closure?
emphysema
Forced Expiratory Manoeuvre (TLC to RV)
FEV1
FVC
FER
RVC (relaxed vital capacity)
are all examples of…
Dynamic Lung Volumes
Dynamic Lung Volumes (5)
Forced Expiratory Manoeuvre (TLC to RV)
FEV1
FVC
FER
RVC (relaxed vital capacity)
What are the potential methods of Bronchial Challenge Testing ?(3)
- Exercise
- Methacholine/Histamine/Mannitol
- Allergens/Chemicals
FEV1/FVC
Forced Expiratory Ratio
Where is impulse oscillometry useful?
In patients (i.e. kids) where it is easier to breathe at tidal volume rather than forced expiratory manoeuvre
Test for measuring static lung volumes
Effort Independent Tests
Helium Dilution Test
Gas trapping in COPD
What are the 3 types of pulmonary function tests that can be carried out?
- Effort dependent tests
- Effort independent tests
- Gas diffusion tests
Which conditions exhibit volume dependent expiratory airway closure?
asthma
chronic bronchitis
In what conditions is Total Lung Transfer for CO reduced? (6)
Why?
Anemia
Emphysema
Interstitial Lung Disease
Pulmonary Oedema
Pulmonary Embolis
Bronchiectasis
Because diffusion is reduced in these conditions
How is airway resistance measured?
Whole body plethysmography
Impulse oscillometry
What are the expected values of…
PEFR
FEV1
FVC
FEV1/FVC Ratio
FEV1 repsonse to ß2 agonists
…in restrictive disease
PEFR - Normal
FEV1 - decreased
FVC - decreased
FEV1/FVC Ratio - >75%
FEV1 repsonse to ß2 agonists - No response
