SM_174a-175a: Pulmonary Function Flashcards
Obstructive lung diseases include _____, _____, and _____
Obstructive lung diseases include emphysema, chronic bronchtis, and asthma
In obstructive lung diseases, the lungs are _____ and may _____ gas
In obstructive lung diseases, the lungs are hyperinflated and may trap gas
In emphysema, _____ elastic recoil pressure _____ resting lung volume, and _____ elastic recoil pressure and tendency of airways to collapse _____ exhalation
In emphsema, decreased elastic recoil pressure elevates resting lung volume, and decreased elastic recoil pressure along with the tendency of airways to collapse limits exhalation
In chronic bronchitis and asthma, airflow obstruction occurs because of _____
In chronic bronchitis and asthma, airflow obstruction occurs because of increased airway resistance
(due to some combo of intraluminal mucus, airway wall edema, bronchospasm, and airway wall remodeling)
An example of a restrictive lung disease is ____
An example of a restrictive lung disease is IPF
Restrictive lung diseases are characterized by ______
Restrictive lung diseases are characterized by low lung volumes
In pulmonary fibrosis, lung volume is decreased because of ______
In pulmonary fibrosis, lung volume is decreased because of increased elastic recoil pressure (decreased lung compliance)
Spirometry measures _____
Spirometry measures expiratory flow rates
FVC = _____ - _____
FVC = TLC - RV
FEV1 is defined as the ____
FEV1 is defined as the forced expiratory volume in the first second of trying
Normal FEV1 / FVC = _____
Normal FEV1 / FVC = 75%
(drops with age)
In obstructive lung disease, FEV1 _____, FVC _____, and FEV1 / FVC _____
In obstructive lung disease, FEV1 decreases, FVC decreases or stays constant, and FEV1 / FVC decreases
( FEV1 / FVC < 0.7 indicates obstructive lung disease)
Why does FEV1 / FVC decrease in obstructive lung disease?
FEV1 / FVC decreases in obstructive lung disease
- FEV1 decreases because of decreased lung elastic recoil pressure or increased airway resistance
- FVC may not fall as much because motivated patients may exhale over a longer period
- This time compensation results in less of a decrease in FVC relative to FEV1, which decreases FEV1 / FVC
In restrictive lung disease, FEV1 ______, FVC ______, and FEV1 / FVC ______
In restrictive lung disease, FEV1 decreases, FVC decreases, and FEV1 / FVC increases
Why does FEV1 / FVC increase in restrictive lung disease?
FEV1 / FVC increases in restrictive lung disease
- Airflow flow rates plotted at isovolume flow (absolute lung volume) may be higher than normal because elastic recoil pressure is higher and airway resistance is lower than normal
- Exhalation time may be shorter than normal
Normalization of FEV1 and FVC following albuterol suggests the patient has _____
Normalization of FEV1 and FVC following albuterol suggests the patient has asthma
(asthma patients can have normal pulmonary function when asymptomatic)
In asthma patients, methacholine causes _____ in spirometric measures that _____ with rescue albuterol
In asthma patients, methacholine causes a drop in spirometric measures that improves with rescue albuterol