Spirometry Flashcards

A patient's FEV1/FVC ratio is 0.65 and FVC is within normal limits. Which pattern does this indicate?

Answer: Obstructive pattern

An FEV1/FVC ratio below 0.70 with normal FVC indicates airflow obstruction (obstructive pattern).

Which spirometry maneuver requires the patient to breathe in as deeply as possible and then exhale as forcefully and completely as possible?

Answer: Forced vital capacity (FVC)

The FVC maneuver requires maximal inhalation followed by a maximal forced exhalation to assess airflow dynamics.

What does the Peak Expiratory Flow (PEF) primarily reflect in a spirometry test?

Answer: Large airway and effort-dependent flow

PEF reflects the function of large central airways and is highly effort-dependent, occurring in the first 100–120 ms of exhalation.

A spirometry report shows FVC = 55% predicted and FEV1/FVC = 0.82. What is the most likely interpretation?

Answer: Restrictive pattern

Reduced FVC with a preserved or elevated FEV1/FVC ratio is the hallmark of a restrictive ventilatory pattern.

Which of the following is the MOST important criterion for acceptability of a spirometry maneuver according to ATS/ERS guidelines?

Answer: Back-extrapolated volume < 150 mL or 5% of FVC

ATS/ERS acceptability criteria require the back-extrapolated volume to be less than 150 mL or 5% of FVC, confirming a sharp, valid start.

In a flow-volume loop, an obstructive pattern is best characterized by:

Answer: Scooping or concavity of the expiratory limb

Obstructive disease causes scooping (concavity) of the expiratory limb of the flow-volume loop due to reduced flow at lower lung volumes.

How many acceptable FVC maneuvers are required before stopping a spirometry test session per ATS/ERS standards?

Answer: At least 3

ATS/ERS guidelines require at least 3 acceptable maneuvers to ensure reproducibility of results.