Comparison of impulse oscillometry and spirometry for detection of airway hyperresponsiveness to methacholine, mannitol, and eucapnic voluntary hyperventilation in children.

Background: Forced expiratory maneuvers are usually difficult in young children. Impulse oscillometry (IOS) requires no active cooperation, is noninvasive, rapid, and easy to perform. This study aimed to compare IOS indexes and forced expiratory volume in 1 second (FEV1) in children for the assessment of bronchial hyperreactivity to methacholine, mannitol, and eucapnic voluntary hyperventilation (EVH).