Impulse Oscillometry and Spirometry Small-Airway Parameters in Mild to Moderate Bronchiectasis

Area of Science:

• Pulmonary Medicine
• Respiratory Physiology

Background:

• Small-airway disorders are common in bronchiectasis.
• Both impulse oscillometry and spirometry can detect these abnormalities.

Purpose of the Study:

• To evaluate the diagnostic utility of impulse oscillometry and spirometry for small-airway parameters in mild to moderate bronchiectasis.
• To assess correlations with radiological findings, disease severity, and sputum bacteriology.
• To validate findings in sensitivity analyses for mild bronchiectasis.

Main Methods:

• 94 subjects with mild to moderate bronchiectasis and 26 healthy controls were recruited.
• Diagnostic value was assessed using receiver operating characteristic curves.
• High-resolution computed tomography (HRCT), impulse oscillometry, spirometry, and sputum cultures were performed.

Main Results:

• Both impulse oscillometry and spirometry parameters distinguished bronchiectasis from controls and correlated with HRCT scores, bronchiectasis severity index, and number of affected lobes (P < .01).
• Parameters were more abnormal in subjects with dyshomogeneity and cystic bronchiectasis.
• Spirometry, unlike impulse oscillometry, showed significant differences between isolated peripheral and peripheral plus central airway involvement (P < .01).

Conclusions:

• Impulse oscillometry and spirometry offer comparable diagnostic value for peripheral airway disorders in bronchiectasis.
• These lung function parameters correlate well with HRCT scores and disease severity indices.
• Incorporating small-airway parameter assessment into future lung function testing for bronchiectasis is recommended.