title: Multiple-breath washout measurements can be significantly shortened in children.
abstract: Multiple-breath washout (MBW)-derived lung clearance index (LCI) is a sensitive measure of ventilation inhomogeneity in patients with cystic fibrosis (CF), but LCI measurement is time consuming. We systematically assessed ways to shorten LCI measurements. In 68 school-aged children (44 with mild CF lung disease) three standard nitrogen (N2) MBWs were applied. We assessed repeatability and diagnostic performance of (1) LCI measured earlier from three MBW runs and (2) LCI measured at complete MBW (1/40th of starting N2 concentration) from two runs only. Compared with the standard LCI from three complete MBW runs, the new LCI based on three N2MBW runs until 1/20th, or two complete runs until 1/40th, provided similar or better repeatability as well as sensitivity and specificity for CF lung disease. Alternative ways to measure LCI reduced test duration in children with CF by 30% and 41%, respectively. LCI measurements can be reliably shortened in children. These new MBW protocols may advance the transition of LCI from research into clinical settings.
authors.affiliation: Department of Paediatrics, University Children's Hospital of Bern, Bern, Switzerland.
authors.forename: Sophie
authors.initials: S
authors.lastname: Yammine
authors.forename: Florian
authors.initials: F
authors.lastname: Singer
authors.forename: Chiara
authors.initials: C
authors.lastname: Abbas
authors.forename: Markus
authors.initials: M
authors.lastname: Roos
authors.forename: Philipp
authors.initials: P
authors.lastname: Latzin
mesh_terms: D000293:Adolescent; D001944:Breath Tests / Q000379:methods*; D002648:Child; D003550:Cystic Fibrosis / Q000175:diagnosis* / Q000503:physiopathology; D045853:Exhalation; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008171:Lung Diseases / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D009585:Nitrogen Dioxide / Q000032:analysis; D012372:ROC Curve
chemical_list: D009585:Nitrogen Dioxide
keywords: Cystic Fibrosis; Lung Physiology; Paediatric Lung Disaese