Which of the following pulmonary function values characterizes an obstructive lung disorder?
I. The forced vital capacity (FVC) is normal or decreased.
II. The forced expiratory volume in 1 second (FEV₁) is decreased.
III. The ratio of residual volume to total lung capacity (RV/TLC) is decreased.
IV. RV is increased.

Question

Quizplus · Accepted Answer

On the basis of spirometry, an obstructive lung disorder is characterized as follows: $\bullet$FVC normal or decreased $\bullet$ FEV₁ decreased $\bullet$ FEV₁/FVC decreased $\bullet$ TLC normal or increased $\bullet$RV increased $\bullet$ RV/TLC increased Table 5-2 in the textbook compares obstructive and restrictive lung diseases in terms of these spirometric measurements.

Which of the Following Pulmonary Function Values Characterizes an Obstructive