Interpretation of Pulmonary Function Tests

Although often said to be a measurement of small airways obstruction, the FEF25-75 is fairly non-specific and reductions can be seen with a number of non-obstructive diseases. Nevertheless, an isolated reduction in the FEF25-75 serves as an important clue to mild obstructive lung disease when the FEV1/FVC ratio is normal. This occurs, for example, in early COPD and in asthmatics when they are ... ................
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