SM 174a, 175a - Pulmonary Function I, II Flashcards
Is the following characteristic of obstructive lung disease or restrictive lung disease?
FEV1/FVC increases
Restrictive
(Even though both FEV1 and FVC decrease, the ratio increases)
What pressures contribute to Palv?
Palv = Ppl + Pel
Which number labels Total Lung Capcity (TLC)?
8
Is the following characteristic of obstructive lung disease or restrictive lung disease?
Decreased FEV1
Both
But more decrease in obstructive than restrictive
Expiratory airflow is decreased most by what combination of pathophysiologic conditions?
a) low Pel and high Raw
b) high Pel and high Raw
c) low Pel and low Raw
d) high Pel and low Raw
a) low Pel and high Raw
Which number labels inspiratory capacity?
7
Is the following characteristic of obstructive lung disease or restrictive lung disease?
Increased RV
Obstructive
Is the following characteristic of obstructive lung disease or restrictive lung disease?
Increased FRC
Obstructive
Is the following characteristic of obstructive lung disease or restrictive lung disease?
Decreased DLCO
Restrictive
(May also decrease in obstructive, or stay the same)
Is the following characteristic of obstructive lung disease or restrictive lung disease?
Increased isovolume flow compared with a normal curve
Restrictive
Flattening of the inspiratory loop suggests:
a) asthma
b) vocal cord paralysis
c) pulmonary fibrosis
d) pulmonary embolism
b) vocal cord paralysis
Inspiratory loop can be flattened by anythign that obstructs the upper (extrathoracic) airway, or inadequate strength of inspiration
Which of the following test results suggests asthma?
- Low FEV1/FVC that normalizes after albuterol
- Low FEV1/FVC with low diffusing capacity
- Normal FEV1/FVC after an irritant challenge
- Normal FEV1/FVC with low diffusing capacity
a. Low FEV1/FVC that normalizes after albuterol
Is the following characteristic of obstructive lung disease or restrictive lung disease?
TLC decreases
Restrictive
What is normal for FEV1/FVC?
~75% in healthy people
Decreases with age
<70% indicates obstructive physiology
How do people with obstructive airflow preserve their FVC, depite obstruction to expiratory air flow?
Time compensation
Healthy people can exhale their FVC in ~4 seconds, but people with obstructive physiology may take 8-10 seconds
What does DLCO measure?
DLCO = diffusing capacity for carbon monoxide
Measures the diffusing capacity across the alveolar membrane
Measures inhaled CO uptake by hemoglobin
(Known [CO] in inhaled air - measured [CO] inexhaled air = uptaken by Hb