Question

question 42 (mandatory) (2 points)
listen
which of the following is associated with restrictive pulmonary disease?
fev₁/fvc ratio is greater than 75%
fev₁/fvc ratio is normal, but the fvc is reduced
fev₁/fvc ratio is less than 50%
none of the above statements are associated with restrictive pulmonary disease

Explanation:

In restrictive pulmonary disease, the main issue is reduced lung expansion, so forced vital capacity (FVC) is decreased. The \( \text{FEV}_1/\text{FVC} \) ratio is typically normal or even increased (since both \( \text{FEV}_1 \) and FVC are reduced, but FVC more? No, actually, in restrictive, FVC is reduced, and \( \text{FEV}_1 \) may also be reduced, but the ratio \( \text{FEV}_1/\text{FVC} \) is normal or high. Wait, the option " \( \text{FEV}_1 /\text{FVC} \) ratio is normal, but the FVC is reduced" matches the pathophysiology: restrictive diseases limit lung volume (so FVC is low), but the rate of airflow (FEV₁ relative to FVC) is normal because the airways are not obstructed (unlike obstructive, where ratio is low). The first option: a ratio >75% is not typical (normal ratio is around 80%, but in restrictive, ratio can be normal or high, but the key is FVC reduced with normal ratio. The third option is for obstructive (like COPD) where ratio is low. So the correct option is the one where ratio is normal but FVC is reduced.

Answer:

B. \( \text{FEV}_1 /\text{FVC} \) ratio is normal, but the FVC is reduced