Reference values for respiratory system impedance by using impulse oscillometry in children aged 2-11 years

Area of Science:

• Pediatric Pulmonology
• Respiratory Physiology
• Medical Instrumentation

Background:

• The forced oscillation technique evaluates respiratory mechanics with minimal patient cooperation, making it suitable for pediatric use.
• Impulse oscillometry (IOS) is a widely available application of this technique.
• Limited reference data exists for IOS in children, hindering its clinical application.

Purpose of the Study:

• To expand the existing reference values for impulse oscillometry variables in healthy children.
• To investigate the correlation between IOS parameters and anthropometric factors like height, weight, and age.
• To provide normative data for impulse oscillometry in pediatric populations.

Main Methods:

• A cohort of 360 healthy children aged 2.1–11.1 years participated in the study.
• Impulse oscillometry (IOS) was used to measure respiratory resistance (Rrs) and reactance (Xrs) at multiple frequencies (5, 10, 15, 20 Hz).
• Total respiratory impedance (Zrs) and resonance frequency (Fr) were also assessed, with all variables related to body height and, to a lesser extent, weight.

Main Results:

• Established reference equations for IOS variables in children aged 2.1–11.1 years, covering height range of 90–160 cm.
• Demonstrated significant correlations between most IOS variables and children's body height.
• Identified weaker correlations between several IOS parameters and body weight.

Conclusions:

• The study successfully extended reference values for impulse oscillometry in children.
• The findings highlight the importance of anthropometric factors, particularly height, in interpreting pediatric IOS results.
• These reference equations will aid in the more accurate clinical assessment of respiratory mechanics in children using IOS.