Pulmonary Function Tests

Obstructive vs restrictive, the A-a gradient, and how to read a flow-volume loop. A rapid, high-yield review of pulmonary function tests for medical students and exam candidates.

In this episode: • Obstructive — ↓ FEV1/FVC < 0.7 • Restrictive — ↓ FVC, normal/↑ ratio • A-a gradient — normal = age/4 + 4 • ↑ A-a — V/Q mismatch, shunt, diffusion • Normal A-a — hypoventilation, altitude

Exam pearl: FEV1/FVC < 0.7 = obstructive

⏱ 4:09 · Quick Medical Review — study smart, not hard. More episodes: https://www.youtube.com/@quickmedicalreview

Covers high-yield pulmonary for USMLE Step 2 CK, MRCP, PLAB and SMLE. Educational revision only — not medical advice.