Diagnostic Approach to Respiratory Disease | Nelson Textbook of Pediatrics 22nd Edition | Spirometry, flow-volume loops, lung volumes, DLCO, bronchodilator response, infant PFT, LCI, FENO, and clinical interpretation.
🌐 paeds.online — Pakistan's Pediatric Platform| Parameter | Obstructive Disease | Restrictive Disease |
|---|---|---|
| FEV1 | ↓↓ (reduced) | ↓ (reduced proportionally) |
| FVC | ↓ or normal | ↓↓ (reduced) |
| FEV1/FVC | ↓ (<0.80) | Normal or ↑ |
| FEF25-75% | ↓↓ (early obstruction) | Normal or low normal |
| TLC | Normal or ↑ (hyperinflation) | ↓↓ |
| RV/TLC | ↑ (air trapping) | Normal or ↑ |
| DLCO | Normal or ↓ (emphysema) | ↓ (loss of parenchyma) |