A patient has pulmonary fibrosis. Which finding is expected on pulmonary function tests?
Answer and explanation
Correct answer: D. Decreased FVC with a normal or increased FEV1/FVC ratio
- Step 1: Fibrosis reduces lung volumes proportionally, so the ratio stays normal or rises. Answer: Decreased FVC with a normal or increased FEV1/FVC ratio. Why not the others: A low ratio with high TLC is obstruction.
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