Acute effects of long-acting bronchodilators on small airways detected in COPD patients by single-breath N2 test and lung P-V curve

In conclusion, bronchodilators reduce the heterogeneity of peripheral airway mechanical properties and the extent of their closure, with minor effects on critical closing pressure. This should lessen the risk of small-airway damage and positively affect gas exchange. NEW & NOTEWORTHY This is the first study investigating in stable chronic obstructive pulmonary disease patients the acute effects of two long-acting bronchodilators, a β-agonist and a muscarinic antagonist, on peripheral airways using simultaneous lung pressure-volume curve and single-breath N2 test. By lessening airway mechanical property heterogeneity, both drugs similarly reduced ventilation inhomogeneity and extent of small-airway closure, as indicated by the decrease of phase III slope, increased oxygen saturation, and fall of closing volume, often below expiratory reserve volume.
Source: Journal of Applied Physiology - Category: Physiology Authors: Tags: RESEARCH ARTICLE Source Type: research