Evaluation of the Double-Tracer Gas Single-Breath Washout Test in a Pediatric Field Study.

BACKGROUND

The early life origins of chronic pulmonary diseases are thought to arise in peripheral small airways. Predictors of ventilation inhomogeneity, a proxy of peripheral airway function, are understudied in schoolchildren.

RESEARCH QUESTION

Is the double-tracer gas single-breath washout (DTG-SBW) measurement feasible in a pediatric field study setting? What are the predictors of the DTG-SBW-derived ventilation inhomogeneity estimate in unselected schoolchildren?

STUDY DESIGN AND METHODS

In this prospective cross-sectional field study, a mobile lung function testing unit visited participating schools in Switzerland. We applied DTG-SBW, fraction of exhaled nitric oxide (Feno), and spirometry measurements. The DTG-SBW is based on tidal inhalation of helium and sulfur-hexafluoride, and the phase III slope (SIII

RESULTS

In 1,782 children, 5,223 DTG-SBW trials were obtained. The DTG-SBW was acceptable in 1,449 children (81.3%); the coefficient of variation was 39.8%. SIII

INTERPRETATION

The DTG-SBW is feasible in a pediatric field study setting. On the population level, age, body composition, and wheeze are independent predictors of peripheral airway function in unselected schoolchildren. The variation of the DTG-SBW possibly constrains its current applicability on the individual level.

TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT03659838; URL: www.

CLINICALTRIALS

gov.

Informations de copyright

Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.

Déclaration de conflit d'intérêts

Financial/Nonfinancial Disclosures The authors have reported to CHEST the following: A.-C. K. is recipient of a Swiss Excellence Grant from the Swiss government. J. M. K. reports funding for this work from a grant from the KinderInsel Bern Foundation. J. U. reports receiving grants or contracts from the Swiss Lung Foundation, Palatin Foundation, University of Basel, and Swiss Cancer League; and payment or honoraria for lectures, presentations, speaker bureaus, manuscript writing, or educational events received from Vertex and the Zürich Lung Foundation, outside the submitted work. P. L. reports receiving grants or contracts from Vertex and OM Pharma paid to the institution; personal payment or honoraria and payments or honoraria for lectures, presentations, speaker bureaus, manuscript writing, or educational events received from Vertex, Vifor, and OM Pharma; personal fees and fees paid to the institution for participation on a data safety monitoring or advisory board for Polyphor, Vertex, OM Pharma, and Vifor; and personal fees for participation on data safety monitoring or advisory board for Santhera (DMC) and Sanofi Aventis. A. M. reports receiving consulting fees from Vertex Pharmaceuticals and Vifor Pharma; payments or honoraria for lectures, presentations, speaker bureaus, manuscript writing, or educational events received from Vertex Pharmaceuticals and Vifor Pharma; participation on a data safety monitoring or advisory board for Vertex Pharmaceuticals; leadership or fiduciary roles in other boards, societies, committees, or advocacy groups, paid or unpaid, held for European Respiratory Society Assembly 7, Swiss Society of Pulmonology Board, Swiss Society of Pediatric Pulmonology Board, Swiss Working Group for Cystic Fibrosis, and Swiss Society for Sleep Research, Sleep Medicine and Chronobiology; and receipt of medical writing from Vertex Pharmaceuticals, with all disclosures made outside the submitted work. F. S. reports support of this manuscript from the Medical University of Graz for the processing charges; grants or contracts from the Medical University of Graz and Lungen Liga Bern paid to the institution; personal payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Novartis Pharma Switzerland, Vertex Pharmaceuticals Switzerland, and Vertex Pharmaceuticals Austria; and nonfinancial support from Chiesi Pharmaceuticals Austria, outside the submitted work. None declared (R. M., E. S. L. P., C. E. K.).