The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Sarath Ranganathan - One of the best experts on this subject based on the ideXlab platform.
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Lung Clearance index and structural Lung disease on computed tomography in early cystic fibrosis
American Journal of Respiratory and Critical Care Medicine, 2015Co-Authors: Kathryn A Ramsey, Tim Rosenow, Lidija Turkovic, Billy Skoric, Georgia Banton, Annemarie Adams, Shannon J Simpson, Conor Murray, Sarath RanganathanAbstract:Rationale: The Lung Clearance index is a measure of ventilation distribution derived from the multiple-breath washout technique. It has been suggested as a surrogate for chest computed tomography to detect structural Lung abnormalities in individuals with cystic fibrosis (CF); however, the associations between Lung Clearance index and early structural Lung disease are unclear.Objectives: We assessed the ability of the Lung Clearance index to reflect structural Lung disease on the basis of chest computed tomography across the entire pediatric age range.Methods: Lung Clearance index was assessed in 42 infants (ages 0–2 yr), 39 preschool children (ages 3–6 yr), and 38 school-age children (7–16 yr) with CF before chest computed tomography and in 72 healthy control subjects. Scans were evaluated for CF-related structural Lung disease using the Perth-Rotterdam Annotated Grid Morphometric Analysis for Cystic Fibrosis quantitative outcome measure.Measurements and Main Results: In infants with CF, Lung Clearance i...
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Lung Clearance index during hospital admission in school-age children with cystic fibrosis
Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society, 2014Co-Authors: Liam Welsh, Christopher Nesci, Haily Tran, Marisol Tomai, Sarath RanganathanAbstract:Abstract Background There is currently limited information regarding Lung Clearance index (LCI) and its response to treatment of pulmonary exacerbations in CF. We aimed to examine the utility of LCI for assessing short term clinical response to IV antibiotic therapy in school-age children with CF. Methods Subjects experiencing exacerbations and hospitalised for IV antibiotics performed both multiple breath nitrogen washout (MBNW) and spirometry on admission to hospital and prior to discharge. Results 27 patients (aged 6–20years) had paired data for MBNW and spirometry. Mean LCI reduced from 12.18 to 11.65 (4.4%) by time of discharge and FEV 1 z -score improved from −3.05 to −2.86 (6.2%). Overall, LCI improved in n=15 (55%) patients compared with n=18 (67%) where FEV 1 improved. Conclusions In summary, these findings do not support the use of LCI (or indeed, FEV 1 ) to gauge the short term clinical response to IV antibiotic therapy in school-age children with cystic fibrosis.
F.h.m. Corstens - One of the best experts on this subject based on the ideXlab platform.
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effect of positive expiratory pressure mask physiotherapy pep versus forced expiration technique fet pd on regional Lung Clearance in chronic bronchitics
European Respiratory Journal, 1991Co-Authors: M Van Hengstum, J Festen, C Beurskens, M Hankel, F Beekman, F.h.m. CorstensAbstract:On theoretical grounds it is assumed that positive expiratory pressure mask physiotherapy (PEP) as a means of promoting mucus Clearance is especially effective in the more distal airways. In a randomized cross-over trial including a control measurement the effect of PEP and of the forced expiration technique combined with postural drainage (FET/PD) on regional Lung Clearance was evaluated in seven patients with chronic bronchitis and abundant sputum production (mean 32 g.day-1). PEP consisted of positive expiratory pressure mask breathing interspersed with breathing exercises, forced expiration manoeuvres (huffing) and, if necessary, coughing. FET consisted of breathing exercises, huffing and also, if necessary, coughing. FET was combined with PD. Following inhalation of a radio-aerosol regional Lung Clearance was estimated by means of gamma camera imaging. The results after PEP appeared to be not significantly different from control. The mean Clearance in all three Lung zones (peripheral, intermediate and inner) was largest after FET/PD as compared with PEP and control. Statistical significance (p less than 0.02) was reached only for Clearance in the inner region. It is concluded that PEP has no demonstrable effect on regional Lung Clearance in these patients.
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Effect of positive expiratory pressure mask physiotherapy (PEP) versus forced expiration technique (FET/PD) on regional Lung Clearance in chronic bronchitics.
The European respiratory journal, 1991Co-Authors: M Van Hengstum, J Festen, C Beurskens, M Hankel, F Beekman, F.h.m. CorstensAbstract:On theoretical grounds it is assumed that positive expiratory pressure mask physiotherapy (PEP) as a means of promoting mucus Clearance is especially effective in the more distal airways. In a randomized cross-over trial including a control measurement the effect of PEP and of the forced expiration technique combined with postural drainage (FET/PD) on regional Lung Clearance was evaluated in seven patients with chronic bronchitis and abundant sputum production (mean 32 g.day-1). PEP consisted of positive expiratory pressure mask breathing interspersed with breathing exercises, forced expiration manoeuvres (huffing) and, if necessary, coughing. FET consisted of breathing exercises, huffing and also, if necessary, coughing. FET was combined with PD. Following inhalation of a radio-aerosol regional Lung Clearance was estimated by means of gamma camera imaging. The results after PEP appeared to be not significantly different from control. The mean Clearance in all three Lung zones (peripheral, intermediate and inner) was largest after FET/PD as compared with PEP and control. Statistical significance (p less than 0.02) was reached only for Clearance in the inner region. It is concluded that PEP has no demonstrable effect on regional Lung Clearance in these patients.
Sanja Stanojevic - One of the best experts on this subject based on the ideXlab platform.
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Lung Clearance Index to Track Acute Respiratory Events in School-Age Children with Cystic Fibrosis.
American journal of respiratory and critical care medicine, 2021Co-Authors: Lucy Perrem, Sanja Stanojevic, Michelle Shaw, Renee Jensen, Nancy Mcdonald, Sarah M. Isaac, M Davis, Charles Clem, Julia Guido, Sylvia JaraAbstract:Rationale: The Lung Clearance index (LCI) is responsive to acute respiratory events in preschool children with cystic fibrosis (CF), but its utility to identify and manage these events in school-ag...
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An observational study of the Lung Clearance index throughout childhood in cystic fibrosis: early years matter.
The European respiratory journal, 2020Co-Authors: Gwyneth Davies, Andrew Bush, Sanja Stanojevic, Emma Raywood, Julie Duncan, Janet Stocks, Sooky Lum, Laura Viviani, Angie Wade, Alistair CalderAbstract:Lung Clearance index (LCI) in the early years was associated with LCI during adolescence in children with cystic fibrosis. Pre-school LCI may help to identify children in whom treatment could be intensified.https://bit.ly/2yKyMbM
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Lung Clearance index response in patients with CF with class III CFTR mutations
Thorax, 2016Co-Authors: Mica Kane, Sanja Stanojevic, Renee Jensen, Tanja Gonska, Julie Avolio, Michelle Klingel, Felix RatjenAbstract:Ivacaftor (KALYDECO) is a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator that increases transmembrane chloride flux in vitro and leads to significant benefits in patients with cystic fibrosis (CF) with class III gating mutations.1–5 Ivacaftor is associated with sustained improvement in FEV1 and weight as well as reduced time to next pulmonary exacerbation.5–7 It has also been shown that 4 weeks of ivacaftor improves the Lung Clearance index (LCI) in patients with CF with preserved Lung function.8 It is presently unclear whether LCI, a measure of ventilation inhomogeneity, provides additional information among patients with more impaired Lung function as well as whether the sustained effectiveness of ivacaftor as demonstrated by improvements in the previously mentioned outcomes is also evident in the LCI response. The aim of this observational study was to assess the LCI before and after initiation of ivacaftor treatment over 6 months in patients with CF with a wider range of …
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Lung Clearance index in cystic fibrosis subjects treated for pulmonary exacerbations
The European respiratory journal, 2015Co-Authors: Nicole Sonneveld, A Horsley, Sanja Stanojevic, Philipp Latzin, Reshma Amin, Jane C. Davies, Paul Aurora, J. Stuart Elborn, Katherine O'neill, Paul RobinsonAbstract:Pulmonary exacerbations are important clinical events for cystic fibrosis (CF) patients. Studies assessing the ability of the Lung Clearance index (LCI) to detect treatment response for pulmonary exacerbations have yielded heterogeneous results. Here, we conduct a retrospective analysis of pooled LCI data to assess treatment with intravenous antibiotics for pulmonary exacerbations and to understand factors explaining the heterogeneous response.A systematic literature search was performed to identify prospective observational studies. Factors predicting the relative change in LCI and spirometry were evaluated while adjusting for within-study clustering.Six previously reported studies and one unpublished study, which included 176 pulmonary exacerbations in both paediatric and adult patients, were included. Overall, LCI significantly decreased by 0.40 units (95% CI -0.60- -0.19, p=0.004) or 2.5% following treatment. The relative change in LCI was significantly correlated with the relative change in forced expiratory volume in 1 s (FEV1), but results were discordant in 42.5% of subjects (80 out of 188). Higher (worse) baseline LCI was associated with a greater improvement in LCI (slope: -0.9%, 95% CI -1.0- -0.4%).LCI response to therapy for pulmonary exacerbations is heterogeneous in CF patients; the overall effect size is small and results are often discordant with FEV1.
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Age and height dependence of Lung Clearance index and functional residual
2013Co-Authors: Sooky Lum, Sanja Stanojevic, Janet Stocks, Angie Wade, Meghan Brown, Padmaja Subbarao, Paul Robinson, Per M. Gustafsson, Paul Aurora, Ah-fong HooAbstract:The Lung Clearance index (LCI) is more sensitive than spirometry in detecting abnormal Lung function in children with cystic fibrosis. LCI is thought to be independent of age, but recent evidence suggests that the upper limit of normal is higher in infants and preschool children than in older subjects. This study examines whether LCI remains independent of body size throughout childhood. Multiple-breath washout data from healthy children and adolescents were collated from three centres using the mass spectrometer system and the inert gas sulfur hexafluoride. Reference equations for LCI and functional residual capacity (FRC) were constructed using the LMS (lambda-mu-sigma) method. Data were available from 497 subjects (2 weeks to 19 years of age) tested on 659 occasions. LCI was dependent on body size, decreasing in a nonlinear pattern as height increased. Changes were particularly marked in the first 5 years of life. Height, age and sex were all independent predictors of FRC. Minimal between-centre differences allowed unified reference equations to be developed.
M Van Hengstum - One of the best experts on this subject based on the ideXlab platform.
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effect of positive expiratory pressure mask physiotherapy pep versus forced expiration technique fet pd on regional Lung Clearance in chronic bronchitics
European Respiratory Journal, 1991Co-Authors: M Van Hengstum, J Festen, C Beurskens, M Hankel, F Beekman, F.h.m. CorstensAbstract:On theoretical grounds it is assumed that positive expiratory pressure mask physiotherapy (PEP) as a means of promoting mucus Clearance is especially effective in the more distal airways. In a randomized cross-over trial including a control measurement the effect of PEP and of the forced expiration technique combined with postural drainage (FET/PD) on regional Lung Clearance was evaluated in seven patients with chronic bronchitis and abundant sputum production (mean 32 g.day-1). PEP consisted of positive expiratory pressure mask breathing interspersed with breathing exercises, forced expiration manoeuvres (huffing) and, if necessary, coughing. FET consisted of breathing exercises, huffing and also, if necessary, coughing. FET was combined with PD. Following inhalation of a radio-aerosol regional Lung Clearance was estimated by means of gamma camera imaging. The results after PEP appeared to be not significantly different from control. The mean Clearance in all three Lung zones (peripheral, intermediate and inner) was largest after FET/PD as compared with PEP and control. Statistical significance (p less than 0.02) was reached only for Clearance in the inner region. It is concluded that PEP has no demonstrable effect on regional Lung Clearance in these patients.
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Effect of positive expiratory pressure mask physiotherapy (PEP) versus forced expiration technique (FET/PD) on regional Lung Clearance in chronic bronchitics.
The European respiratory journal, 1991Co-Authors: M Van Hengstum, J Festen, C Beurskens, M Hankel, F Beekman, F.h.m. CorstensAbstract:On theoretical grounds it is assumed that positive expiratory pressure mask physiotherapy (PEP) as a means of promoting mucus Clearance is especially effective in the more distal airways. In a randomized cross-over trial including a control measurement the effect of PEP and of the forced expiration technique combined with postural drainage (FET/PD) on regional Lung Clearance was evaluated in seven patients with chronic bronchitis and abundant sputum production (mean 32 g.day-1). PEP consisted of positive expiratory pressure mask breathing interspersed with breathing exercises, forced expiration manoeuvres (huffing) and, if necessary, coughing. FET consisted of breathing exercises, huffing and also, if necessary, coughing. FET was combined with PD. Following inhalation of a radio-aerosol regional Lung Clearance was estimated by means of gamma camera imaging. The results after PEP appeared to be not significantly different from control. The mean Clearance in all three Lung zones (peripheral, intermediate and inner) was largest after FET/PD as compared with PEP and control. Statistical significance (p less than 0.02) was reached only for Clearance in the inner region. It is concluded that PEP has no demonstrable effect on regional Lung Clearance in these patients.
A Horsley - One of the best experts on this subject based on the ideXlab platform.
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Lung Clearance index in cystic fibrosis subjects treated for pulmonary exacerbations
The European respiratory journal, 2015Co-Authors: Nicole Sonneveld, A Horsley, Sanja Stanojevic, Philipp Latzin, Reshma Amin, Jane C. Davies, Paul Aurora, J. Stuart Elborn, Katherine O'neill, Paul RobinsonAbstract:Pulmonary exacerbations are important clinical events for cystic fibrosis (CF) patients. Studies assessing the ability of the Lung Clearance index (LCI) to detect treatment response for pulmonary exacerbations have yielded heterogeneous results. Here, we conduct a retrospective analysis of pooled LCI data to assess treatment with intravenous antibiotics for pulmonary exacerbations and to understand factors explaining the heterogeneous response.A systematic literature search was performed to identify prospective observational studies. Factors predicting the relative change in LCI and spirometry were evaluated while adjusting for within-study clustering.Six previously reported studies and one unpublished study, which included 176 pulmonary exacerbations in both paediatric and adult patients, were included. Overall, LCI significantly decreased by 0.40 units (95% CI -0.60- -0.19, p=0.004) or 2.5% following treatment. The relative change in LCI was significantly correlated with the relative change in forced expiratory volume in 1 s (FEV1), but results were discordant in 42.5% of subjects (80 out of 188). Higher (worse) baseline LCI was associated with a greater improvement in LCI (slope: -0.9%, 95% CI -1.0- -0.4%).LCI response to therapy for pulmonary exacerbations is heterogeneous in CF patients; the overall effect size is small and results are often discordant with FEV1.
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Lung Clearance index in adults with non-cystic fibrosis bronchiectasis
Respiratory research, 2014Co-Authors: Sherif Gonem, Per E Gustafsson, Alys Scadding, Marcia Soares, Amisha Singapuri, Chandra M. Ohri, Simon Range, Christopher E. Brightling, Ian D. Pavord, A HorsleyAbstract:Background Lung Clearance index (LCI) is a measure of abnormal ventilation distribution derived from the multiple breath inert gas washout (MBW) technique. We aimed to determine the clinical utility of LCI in non-CF bronchiectasis, and to assess two novel MBW parameters that distinguish between increases in LCI due to specific ventilation inequality (LCIvent) and increased respiratory dead space (LCIds).
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Lung Clearance index in adults with non cystic fibrosis bronchiectasis
Respiratory Research, 2014Co-Authors: Sherif Gonem, Per E Gustafsson, Alys Scadding, Marcia Soares, Amisha Singapuri, Chandra M. Ohri, Simon Range, Christopher E. Brightling, Ian D. Pavord, A HorsleyAbstract:Lung Clearance index (LCI) is a measure of abnormal ventilation distribution derived from the multiple breath inert gas washout (MBW) technique. We aimed to determine the clinical utility of LCI in non-CF bronchiectasis, and to assess two novel MBW parameters that distinguish between increases in LCI due to specific ventilation inequality (LCIvent) and increased respiratory dead space (LCIds). Forty-three patients with non-CF bronchiectasis and 18 healthy control subjects underwent MBW using the sulphur hexafluoride wash-in technique, and data from 40 adults with CF were re-analysed. LCIvent and LCIds were calculated using a theoretical two-compartment Lung model, and represent the proportional increase in LCI above its ideal value due to specific ventilation inequality and increased respiratory dead space, respectively. LCI was significantly raised in patients with non-CF bronchiectasis compared to healthy controls (9.99 versus 7.28, p 0.75), and correlated significantly with measures of spirometric airflow obstruction. LCI is repeatable, discriminatory, and is associated with spirometric airflow obstruction in patients with non-CF bronchiectasis. LCIvent and LCIds are a practical and repeatable alternative to phase III slope analysis and may allow a further level of mechanistic information to be extracted from the MBW test in patients with severe ventilation heterogeneity.
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Lung Clearance index is a repeatable and sensitive indicator of radiological changes in bronchiectasis
American Journal of Respiratory and Critical Care Medicine, 2014Co-Authors: Stephen Rowan, Judy Bradley, Ian Bradbury, John Lawson, Tom Lynch, Per E Gustafsson, A Horsley, Katherine Oneill, Madeleine Ennis, Stuart J ElbornAbstract:Rationale: In bronchiectasis there is a need for improved markers of Lung function to determine disease severity and response to therapy.Objectives: To assess whether the Lung Clearance index is a repeatable and more sensitive indicator of computed tomography (CT) scan abnormalities than spirometry in bronchiectasis.Methods: Thirty patients with stable bronchiectasis were recruited and Lung Clearance index, spirometry, and health-related quality of life measures were assessed on two occasions, 2 weeks apart when stable (study 1). A separate group of 60 patients with stable bronchiectasis was studied on a single visit with the same measurements and a CT scan (study 2).Measurements and Main Results: In study 1, the intervisit intraclass correlation coefficient for the Lung Clearance index was 0.94 (95% confidence interval, 0.89 to 0.97; P < 0.001). In study 2, the mean age was 62 (10) years, FEV1 76.5% predicted (18.9), Lung Clearance index 9.1 (2.0), and total CT score 14.1 (10.2)%. The Lung Clearance inde...
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Lung Clearance index in the assessment of airways disease
Respiratory Medicine, 2009Co-Authors: A HorsleyAbstract:In the last few years there has been a growing interest in Lung Clearance index (LCI), a measure of Lung physiology derived from multiple breath washout tests. This resurgence of interest was initially driven by the recognition that such assessments were capable of detecting early airways disease in children, and are more sensitive and easier to perform in this population than conventional Lung function tests [Aurora P, Kozlowska W, Stocks J. Gas mixing efficiency from birth to adulthood measured by multiple-breath washout. Respir Physiol Neurobiol, 2005;148(1-2):125-39]. With an appreciation of the importance of earlier identification of airways dysfunction, and prevention of irreversible structural airway changes, methods of following airways disease in these "silent years" are especially important. LCI has now been reported in studies involving all age groups, from infants to adults [Lum S, Gustafsson P, Ljungberg H, Hulskamp G, Bush A, Carr SB, et al. Early detection of cystic fibrosis Lung disease: multiple-breath washout versus raised volume tests. Thorax, 2007;62(4):341-7; Horsley AR, Gustafsson PM, Macleod K, Saunders CJ, Greening AP, Porteous D, et al. Lung Clearance index is a sensitive, repeatable and practical measure of airways disease in adults with cystic fibrosis. Thorax, 2008;63:135-40], and has a narrow range of normal over this wide age range, making it especially suitable for long-term follow-up studies. In cystic fibrosis (CF) particularly, there is a pressing need for sensitive and repeatable clinical endpoints for therapeutic interventions [Rosenfeld M. An overview of endpoints for cystic fibrosis clinical trials: one size does not fit all. Proc Am Thorac Soc, 2007;4(4):299-301], and LCI has been proposed as an outcome measure in future CF gene therapy studies [Davies JC, Cunningham S, Alton EW, Innes JA. Lung Clearance index in CF: a sensitive marker of Lung disease severity. Thorax, 2008;63(2):96-7]. This review will consider how LCI is derived, how it differs from conventional Lung function testing, and its applications and limitations.
