Interpretation of Pulmonary Function Tests

We consider obstruction reversible is there is a 12% or greater increase in the FVC or FEV1 after a bronchodilator challenge. We use an albuterol inhaler as our standard but the PFT laboratory will do the challenge test with ipratropium bromide (Atrovent) if requested. Another value that is given with spirometry is the FEF25-75, or mid-flow rate. ................
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