Multiple-Breath Washout Outcomes Are Sensitive to Inflammation and Infection in Children with Cystic Fibrosis

Self Cite

Background The multiple breath washout (MBW) test may be most useful in tracking disease progression over time to inform treatment decisions. In the clinical setting, alternative outcomes, which can be obtained quickly and easily, may facilitate interpretation of clinically relevant changes in lung function. Methods In this secondary analysis of data from 78 cystic fibrosis (CF) and 72 healthy control (HC) subjects between the ages of 2.6 and 5.9 years, MBW was performed at enrollment, 1, 3, 6, 9, and 12 months, as well as during symptomatic visits using the Exhalyzer D (EcoMedics AG, Duernten, Switzerland). The lung clearance index, LCI2.5, was compared to moment ratios (M1/M0 and M2/M0) at the standard cutoff (1/40th of starting tracer gas concentration) as well as LCI5 and moment ratios at 1/20th of the starting concentration (M1/M0 at LCI5, and M2/M0 at LCI5). Results All outcomes were able to distinguish between health and disease. LCI5 reduced testing time by 40% and increased feasibility by more than 10%. The limits of biological reproducibility in healthy children were similar between LCI2.5 (15%), LCI5 (12%), M1/M0 at LCI2.5 (14%), and M1/M0 at LCI5 (12%), but markedly larger for M2/M0 at LCI2.5 (30%) and M2/M0 at LCI5 (25%). Each outcome deteriorated significantly with worsening pulmonary symptoms, the magnitude of deterioration was greatest for M2/M0. Conclusions In preschool children with CF, LCI5 was more feasible to obtain and track disease progression. The second moment ratio was most sensitive to pulmonary symptoms, but had the greatest variability both within and between subjects.

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

The utility of moment ratios and abbreviated endpoints of the multiple breath washout test in preschool children with cystic fibrosis

Shaw

Oppelaar

Jensen

et al. 2020

Self Cite

“…Both DTG‐SBW and N 2 MBW measurements were performed using a validated and commercially available device (Exhalyzer D system, Eco Medics AG, Duernten, Switzerland) according to consensus guidelines . For data recording, we used Spiroware 3.1.6.…”

Section: Methodsmentioning

confidence: 99%

“…N 2 MBW was performed to assess markers for global and peripheral ventilation distribution . For this test the subject breaths 100% O 2 to wash out resident N 2 gas from the lungs.…”

Section: Methodsmentioning

confidence: 99%

“…Among lung function techniques, the multiple‐breath washout (MBW) test has gained increasing interest as a sensitive, non‐invasive test for assessment of ventilation distribution in children with CF . The most commonly reported outcome is the lung clearance index (LCI), calculated as a ratio of the cumulative expired volume needed to wash out a tracer gas, divided by the functional residual capacity.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Single‐breath washout and association with structural lung disease in children with cystic fibrosis

Yammine

Ramsey

King

et al. 2019

Self Cite

Background: In children with cystic fibrosis (CF) lung clearance index (LCI) from multiple-breath washout (MBW) correlates with structural lung disease. As a shorter test, single-breath washout (SBW) represents an attractive alternative to assess the ventilation distribution, however, data for the correlation with lung imaging are lacking. Methods:We assessed correlations between phase III slope (SIII) of double-tracer gas SBW, nitrogen MBW indices (LCI and moment ratios for overall ventilation distribution, Scond, and Sacin for conductive and mainly acinar ventilation, respectively) and structural lung disease assessed by chest computed tomography (CT) in children with CF.Results: In a prospective cross-sectional study data from MBW, SBW, and chest CT were obtained in 32 children with CF with a median (range) age of 8.2 (5.2-16.3) years.Bronchiectasis was present in 24 (75%) children and air trapping was present in 29 (91%). Median (IQR) SIII of SBW was −138.4 (150.6) mg/mol. We found no association between SIII with either the MBW outcomes or CT scores (n = 23, association with bronchiectasis extent r = 0.10, P = 0.64). LCI and Scond were associated with bronchiectasis extent (n = 23, r = 0.57, P = 0.004; r = 0.60, P = 0.003, respectively).Conclusions: Acinar ventilation inhomogeneity measured by SBW was not associated with structural lung disease on CT. Double-tracer SBW added no benefit to indices measured by MBW.

Regional ventilation inhomogeneity in survivors of extremely preterm birth

Arigliani

Valentini

Stocco

et al. 2020

IntroductionSurvivors of extreme prematurity may have disrupted lung development. We hypothesized that the multiple breath washout (MBW) index Scond, which is intended to reflect ventilation inhomogeneity from the conducting airways, could be a sensitive marker of respiratory impairment in this group.MethodsSpirometry, TLco, and MBW were cross‐sectionally evaluated at 8 to 14 years of age in children born at <28 weeks between 2004 and 2010 in Udine, Italy. Age‐matched controls born at term were also included. Bronchopulmonary dysplasia (BPD) was defined as oxygen‐dependence at 36 weeks postmenstrual age. The limits of normal were the 5th percentile of the reference population (Global Lung Initiative) for spirometry and TLco and the 95th percentile of controls for Lung Clearance Index, Scond, and Sacin from MBW.ResultsResults were obtained in 47 extremely preterm children (53% boys, mean ± standard deviation age 11.3 ± 2.0 years, 40% with BPD) and 60 controls (50% boys, 11.6 ± 1.9 years). There were significant differences between preterm children and controls in all lung function outcomes, except for Sacin. Among children born <28 weeks, Scond tended to be frequently abnormal than FEV1 z‐score (29% vs 14%, P = .06). At multivariable linear regression, in the preterm group, current asthma was significantly associated with a higher Scond (B = 0.019, 95% confidence interval, 0.000‐0.038), whereas BPD was not.ConclusionAlmost a third of extremely preterm children at school age showed Scond alterations that affected also children without BPD. Longitudinal studies should clarify the prognostic meaning of Scond abnormalities in this group.