Abstract
Oscillatory reactance (Xrs) is markedly dependent by the frequency of the oscillatory pressure. The frequency at which Xrs crosses zero is called resonant frequency(Fres) and the area of the reactance spectrum from the lowest stimulating frequency to Fres is indicated as Area of Reactance(Ax). Despite their use to investigate peripheral lung mechanics and for the evaluation of bronchial reversibility tests (King et al. ERJ 2020), no data exists about their dependence on stimulating waveforms.
We studied the effects of different stimulating waveforms on the derivation of Ax and Fres using 2 stimuli: a pseudorandom signal containing prime numbers from 5 to 37 Hz and a multi-frequency waveform containing only 5,11, and 19 Hz components.
In total, 36 asthmatic children (6.4-12.9 yrs; 112-174 cm) were measured using the 2 different waveforms in random order with a commercial oscillometry device (RESMON PRO FULL, RESTECH, Italy). Measurements were performed in triplicate and repeated after the administration of bronchodilator. Pooled data PRE and Post-BD were compared using the Bland-Altman method and differences evaluated against published values of short-term variability.
Using the 2 examined waveforms did not introduce any significant bias and observed differences were consistent with expected short-term variability supporting the equivalence of the 2 waveforms for the derivation of Ax and Fres.
Footnotes
Cite this article as Eur Respir J 2022; 60: Suppl. 66, 4603.
This article was presented at the 2022 ERS International Congress, in session “-”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2022
