Pulmonary function tests Flashcards
(25 cards)
Briefly describe obstructive lung diseases
Obstructive diseases are characterised by increased resistance to air MOVING OUT and a HYPERINFLATED LUNG
Briefly describe restrictive lung diseases
Restrictive diseases are characterised by increased resistance to air MOVING IN and a HYPERDEFLATED LUNG
What are the categories of pulmonary function tests?
- Volume
- Capacity
- Flow
- Diffusion studies
- Resp muscle strength
What is the normal breathing term called?
Tidal volume
What is the volume of air always present during maximal expiration called?
Residual volume
The maximum amount of air that can be inhaled during normal inspiration
Inspiratory reserve volume
The maximum amount of air that can be exhaled during normal expiration
Expiratory reserve volume
What makes up total lung capacity?
Residual volume and vital capacity
What is vital capacity?
The combination of inspiratory reserve volume, tidal volume and expiratory reserve volume
What makes up inspiratory capacity?
tidal volume and inspiratory reserve volume
What makes up functional residual capacity
residual volume and expiratory reserve volume
What are the 4 lung capacities?
- Vital Capacity (VC)
- Inspiratory Capacity (IC)
- Functional Residual Capacity (FRC)
- Total Lung Capacity (TLC)
What are the 4 lung volumes?
Tidal volume, insp reserve volume, expiratory reserve volume, and residual volume
What are the conditions with decreased tidal volume?
restrictive disease, lung cancer, atelectasis, MSK impairment
What are the conditions with decreased ERV?
pneumothroax, pleural effusion, ascites
What is the key thing to remember between restrictive and obstructive?
All lung volumes are greater with obstructive and all lung volumes are less with restrictive
What are the 3 measures for flow?
FEV (forced expiratory volume), FVC (forced vital capacity), FEV1 over FVC%
What is forced vital capacity? FVC
The maximum amout of air that can be expired after max inhalation
What is an obstructive disease identifier on a flow chart?
Low FEV1 and low FEV1/FVC%
What is a restrictive disease identifier on a flow chart?
Low FVC
Differentiate between the GOLD classifications of COPD
- FEV1> 80% predicted = MILD
- FEV1 50-80% predicted = MODERATE
- FEV1 30-50% predicted = SEVERE
- FEV1 <30% predicted or FEV1 <50% preductive + chronic resp failure = VERY SEVERE
What is a diffusion study?
Diffusion capacity of carbon monoxide (measure functioning of gas exchange from lungs (alveoli) to blood (capillaries)
What does LOW DLCO mean?
problem with either pulmonary or circulatory system (emphysema, fibrosis, anemia)
What does HIGH DLCO mean?
problem with the circulatory system (polycythemia or increased red blood cells) NOT pulmonary
RBCs have a high affinity for CO2 over O2