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🌱 來自: Huppert’s Notes
Pulmonary Function Testing (PFTs)🚧 施工中
Pulmonary Function Testing (PFTs)
• Approach to interpreting PFTs:
- Key questions:
• Is there obstruction?
• Is there restriction?
• Is there pathology disruptive to the alveolar–capillary membrane?
- Approach: See Figures 2.8 and 2.9
FIGURE 2.8: PFT Flow–volume loops in health and disease. In obstructive disease, the flow–volume loop becomes curvilinear, whereas in restrictive disease the flow–volume loop becomes steep/vertical.
FIGURE 2.9: An approach to PFT interpretation. Abbreviations: PFT = Pulmonary function test; FEV1 = forced expiratory volume in one second; FVC = forced vital capacity; DLCO = diffusion capacity for carbon monoxide; Wnl = within normal limits; ILD = interstitial lung disease; NM = neuromuscular disorder; Hct = hematocrit
• Assess flow–volume loop, if available (curvilinear = obstructive; steep/vertical = restrictive)
• Evaluate FEV1/FVC (<0.7 = obstructive)
- If obstructive, assess reversibility and DLCO to determine etiology
• Evaluate TLC (<80% predicted = restrictive)
- If restrictive, assess DLCO to determine etiology
• Evaluate DLCO
- Consider methacholine challenge, as asthma may have baseline normal FEV1/FVC, TLC, DLCO