Objective measures of lung function are important in the diagnosis and management of
asthma, yet most preschoolers cannot perform spirometry.
Impulse oscillometry, which is performed during tidal breathing, is a method by which lung
function measures can be obtained in preschool children.
Impulse oscillometry can be useful in determining baseline lung function, demonstrating
response to bronchodilator or bronchoprovocation, and predicting asthma exacerbations
and loss of disease control.
Fractional exhaled nitric oxide (FeNO) levels reflect eosinophilic inflammation and predict
responsiveness to corticosteroids.
Although FeNO has been used to discriminate among wheezing phenotypes, the role of
FeNO in preschool wheezing remains unclear.
Preschool asthma, Pulmonary function testing, Impulse oscillometry, Impedance, Resistance, Reactance, Coherence, Tidal breathing