Measurement of airway resistance using the interrupter technique in preschool children in the ambulatory setting

Area of Science:

• Pediatric Pulmonology
• Respiratory Physiology

Background:

• Assessing airway resistance in young children is challenging.
• The interrupter technique (Rint) offers a potential non-invasive method.
• Evaluating bronchodilator response is crucial for diagnosing and managing pediatric respiratory conditions.

Purpose of the Study:

• To determine the feasibility, repeatability, and interrater reliability of the interrupter technique for measuring airway resistance in children aged 2-5 years.
• To assess the ability to demonstrate bronchodilator reversibility in wheezy preschool children using this technique.

Main Methods:

• Measurements of airway resistance using the interrupter technique were performed on children aged 2-5 years.
• Feasibility was assessed by successful completion of baseline and post-bronchodilator measurements.
• Repeatability was evaluated by comparing measurements taken 30 seconds apart and after placebo.
• Interrater reliability was assessed by comparing measurements from two independent testers.

Main Results:

• Feasibility of baseline testing increased with age, from 56% in 2-3 year olds to 95% in 4-5 year olds.
• Repeatability coefficients were low (0.15-0.21 kPa·L⁻¹·s), indicating good precision.
• Interrater reliability was also good (0.15 kPa·L⁻¹·s).
• Bronchodilator reversibility was demonstrated in most wheezy children, using a threshold of 0.21 kPa·L⁻¹·s.

Conclusions:

• The interrupter technique is a feasible and reliable method for measuring airway resistance in preschool children in ambulatory settings.
• The technique can successfully demonstrate bronchodilator reversibility in wheezy children.
• This method holds promise as a valuable clinical and research tool for pediatric respiratory assessment.