title: Changes in multiple breath washout measures after raised volume rapid thoracoabdominal compression maneuvers in infants.
abstract: Multiple breath inert gas washout (MBW) measurements in infants are performed supine and often obtained under sedation and thus are combined with other lung function tests such as raised volume rapid thoracoabdominal compression (RVRTC). In this study, we sought to determine the effects of RVRTC maneuvers on MBW measures. Compared with tests performed prior to RVRTC, MBW measured after RVRTC was associated with a small reduction in functional residual capacity and a more pronounced decrease in cumulative expired volume in both healthy children and children with obstructive lung disease (cystic fibrosis or recurrent wheeze) indicating a more efficient washout after the raised volume maneuvers. Lung Clearance Index (LCI) decreased significantly in infants with respiratory disease (change in LCI of -0.24 units post RVRTC; standard error (SE) ± 0.07 units; P = 0.0004), but not in healthy infants (change in LCI of -0.08 units; SE ± 0.11 units; P = 0.44). As the RVRTC maneuver affects MBW measurements in infants, the timing of testing procedures needs to be standardized in longitudinal studies.
authors.affiliation: Department of Pediatrics and Program in Physiology and Experimental Medicine, Division of Respiratory Medicine, SickKids Research Institute, The Hospital for Sick Children and University of Toronto, Toronto, Canada.
authors.forename: Padmaja
authors.initials: P
authors.lastname: Subbarao
authors.affiliation: Department of Pediatrics and Program in Physiology and Experimental Medicine, Division of Respiratory Medicine, SickKids Research Institute, The Hospital for Sick Children and University of Toronto, Toronto, Canada.
authors.forename: Zihang
authors.initials: Z
authors.lastname: Lu
authors.affiliation: Department of Pediatrics and Program in Physiology and Experimental Medicine, Division of Respiratory Medicine, SickKids Research Institute, The Hospital for Sick Children and University of Toronto, Toronto, Canada.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Kowalik
authors.affiliation: Department of Pediatrics and Program in Physiology and Experimental Medicine, Division of Respiratory Medicine, SickKids Research Institute, The Hospital for Sick Children and University of Toronto, Toronto, Canada.
authors.forename: Meghan
authors.initials: M
authors.lastname: Brown
authors.affiliation: Department of Pediatrics and Program in Physiology and Experimental Medicine, Division of Respiratory Medicine, SickKids Research Institute, The Hospital for Sick Children and University of Toronto, Toronto, Canada.
authors.forename: Susan
authors.initials: S
authors.lastname: Balkovec
authors.affiliation: Department of Pediatrics, Central Hospital, Skövde, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Gustafsson
authors.affiliation: Dalla Lana School of Public Health, University of Toronto, Toronto, Canada.
authors.forename: Wendy
authors.initials: W
authors.lastname: Lou
authors.affiliation: Department of Pediatrics and Program in Physiology and Experimental Medicine, Division of Respiratory Medicine, SickKids Research Institute, The Hospital for Sick Children and University of Toronto, Toronto, Canada.
authors.forename: Felix
authors.initials: F
authors.lastname: Ratjen
mesh_terms: D001944:Breath Tests / Q000379:methods*; D016022:Case-Control Studies; D003550:Cystic Fibrosis / Q000503:physiopathology*; D005260:Female; D005652:Functional Residual Capacity; D006801:Humans; D007223:Infant; D016018:Least-Squares Analysis; D016014:Linear Models; D008168:Lung / Q000503:physiopathology*; D008297:Male; D010993:Plethysmography, Whole Body; D012129:Respiratory Function Tests / Q000379:methods*; D012135:Respiratory Sounds / Q000503:physiopathology*
keywords: infant; lung clearance index; multiple breath washout; pulmonary function tests; raised volume