RRT Pulmonary Function Testing Flashcards
6 cards from real RRT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 RRT Pulmonary Function Testing flashcards as text
Which spirometric pattern is characterized by reduced FVC with a normal or elevated FEV1/FVC ratio?
Answer: Restrictive pattern
A restrictive pattern shows proportional reduction in FVC and FEV1, maintaining or elevating the FEV1/FVC ratio above normal (≥0.70).
What FEV1/FVC ratio defines airflow obstruction in spirometry?
Answer: Less than 0.70
The GOLD criteria define airflow obstruction as a post-bronchodilator FEV1/FVC ratio below 0.70, indicating COPD.
Diffusing capacity for carbon monoxide (DLCO) is reduced in which condition?
Answer: Emphysema
Emphysema destroys alveolar walls and capillaries, reducing the surface area available for gas exchange and lowering DLCO.
What is residual volume (RV) and how is it measured?
Answer: Volume remaining after maximal expiration; measured by body plethysmography or gas dilution
Residual volume is the air remaining in the lungs after maximal exhalation; it cannot be measured by spirometry alone, requiring body plethysmography or gas dilution techniques.
A patient with asthma shows significant improvement in FEV1 after bronchodilator administration. What percentage increase is considered significant?
Answer: 12% and 200 mL
A post-bronchodilator increase of ≥12% and ≥200 mL in FEV1 is considered a significant positive bronchodilator response, suggesting reversible obstruction.
Total lung capacity (TLC) is defined as:
Answer: Total volume of air in the lungs at maximal inhalation
TLC is the sum of all lung volumes (RV + ERV + TV + IRV) and represents the maximum amount of air the lungs can hold.