Sensitivity of bronchial responsiveness measurements in young infants

Area of Science:

• Pediatric Pulmonology
• Respiratory Physiology
• Infant Lung Function Testing

Background:

• Evaluating infant lung function is challenging due to limited evidence on preferred methods.
• Assessing airway obstruction and bronchial responsiveness in infants requires sensitive and repeatable techniques.

Purpose of the Study:

• To compare the sensitivity and repeatability of different lung function indexes in young infants during induced airway obstruction.
• To identify optimal methods for measuring baseline lung function and bronchial responsiveness in infants.

Main Methods:

• The study involved 402 infants (median age, 6 weeks).
• Forced flow-volume measurements (raised volume rapid thoracoabdominal compression) were compared with tidal breathing indexes, transcutaneous oxygen (Ptco(2)), and auscultation during methacholine challenge.
• Sensitivity and repeatability of various parameters were assessed.

Main Results:

• Transcutaneous oxygen (Ptco(2)) demonstrated the highest sensitivity in detecting airway obstruction during methacholine challenge.
• Forced expiratory volume at 0.5 seconds (FEV(0.5)) was the second most sensitive parameter.
• Both Ptco(2) and FEV(0.5) outperformed other spirometry and tidal breathing indexes, with low coefficients of variation (4% for Ptco(2), 7% for FEV(0.5)).

Conclusions:

• Transcutaneous oxygen (Ptco(2)) and FEV(0.5) are the most sensitive parameters for assessing bronchial responsiveness in infants.
• FEV(0.5) is recommended for baseline lung function measurements.
• Ptco(2) is best for assessing bronchial responsiveness, offering feasibility for studies in non-sedated infants.