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.

Ventilation inhomogeneity in infants with recurrent wheezing

“…Performing multiple infant pulmonary function measures is challenging because of the observed effects of RVRTC on LCI 19. LCI was always performed first and thus impacted our ability to generate flow data in all of our subjects.…”

Therapeutic Blowing Toys: Does the Overlap of Ventilatory Stimuli Alter the Respiratory Mechanics of Healthy Schoolchildren?

“…21 In the present investigation, there was a reduction in Z5, probably as a consequence of the reduction in R5. This represents the total airway R, 22 and the fact that there was no change in R20 related to the central airway R indicates that blow toys have a positive effect on the most peripheral portion of the bronchial tree. This information can be reinforced by the Fres parameter, which refers to peripheral airway behavior and has also shown improved values after intervention.…”

Patterns of health care use related to respiratory conditions in early life: A birth cohort study with linked administrative data

“…This study has several limitations. First, CHILD families were predominantly urban residents and typically with high socioeconomic status . As such, a floor effect might have occurred when we sought to identify differences between the two HSU groups in terms of indoor air pollution and poor nutrition—risk factors well known for childhood respiratory conditions .…”

“…First, CHILD families were predominantly urban residents and typically with high socioeconomic status. 13 As such, a floor effect might have occurred when we sought to identify differences between the two HSU groups in terms of indoor air pollution and poor nutrition-risk factors well known for childhood respiratory conditions. 29 Second, we were unable to obtain medication data for these children through the Ontario administrative databases, as the latter only capture medication claims for residents aged over 65 years and residents on social assistance.…”

“…In 2008, the Canadian Healthy Infant Longitudinal Development (CHILD) Study was launched to investigate the development of asthma and atopic diseases in relation to genetic status and prenatal and postnatal environmental exposures. 13,14 Linking this birth cohort to provincial population-based health administrative databases provides a rich platform to reliably track all the health care encounters, expenses, and diagnoses of study participants while accounting for symptoms, lung function, and prenatal and postnatal health determinants. We applied a model-based cluster analysis with a multivariate longitudinal framework to the linked data to identify distinctive patterns of respiratory-related health services use (HSU) in early life-associated risk factors and future outcomes.…”