Caroline Beardsmore - Academia.edu (original) (raw)

Papers by Caroline Beardsmore

PloS one, 2016

Spirometry datasets from South-Asian children were collated from four centres in India and five w... more Spirometry datasets from South-Asian children were collated from four centres in India and five within the UK. Records with transcription errors, missing values for height or spirometry, and implausible values were excluded(n = 110). Following exclusions, cross-sectional data were available from 8,124 children (56.3% male; 5-17 years). When compared with GLI-predicted values from White Europeans, forced expired volume in 1s (FEV1) and forced vital capacity (FVC) in South-Asian children were on average 15% lower, ranging from 4-19% between centres. By contrast, proportional reductions in FEV1 and FVC within all but two datasets meant that the FEV1/FVC ratio remained independent of ethnicity. The 'GLI-Other' equation fitted data from North India reasonably well while 'GLI-Black' equations provided a better approximation for South-Asian data than the 'GLI-White' equation. However, marked discrepancies in the mean lung function z-scores between centres especially...

European Respiratory Journal, Sep 1, 2014

American Journal of Respiratory and Critical Care Medicine, Feb 14, 2014

European Respiratory Journal, 2015

Bulletin européen de physiopathologie respiratoire

Respiratory system compliance (Crs) was measured in 34 spontaneously breathing infants during the... more Respiratory system compliance (Crs) was measured in 34 spontaneously breathing infants during the first year of life. An occlusion technique was used whereby several expiratory occlusions were performed at different lung volumes within the tidal range. The airway opening pressure generated during a plateau after occlusion was related to the volume included above the end-tidal level by a regression equation. The slope of this equation represented the compliance of the infant's respiratory system; the intercept was significantly different for preterm (-0.5 ml) and post-term (-5.5 ml) infants and may represent the difference between end-expiratory lung volume during tidal breathing and the relaxed functional residual capacity. The values for respiratory system compliance were similar to those previously reported for infants during muscle relaxation. As a function of body length, Crs = 1.58 X length3.13 X 10(-4) ml . kPa-1. The technique described is simple to apply and is independent of oesophageal pressure measurements.

Journal of applied physiology: respiratory, environmental and exercise physiology

Thoracic gas volume (TGV) was measured with a whole-body plethysmograph in 20 infants at function... more Thoracic gas volume (TGV) was measured with a whole-body plethysmograph in 20 infants at functional residual capacity (FRC) and at a series of higher lung volumes achieved by artificial inflation of the lungs with known volumes of air after airway occlusion. There was a discrepancy between the corrected values of TGV measured at high and low lung volumes in nine infants; in six cases TGV measured at high lung volumes exceeded that measured at FRC, and in three cases it was reduced when compared with the measurement made at FRC. These changes were not related to age, size, or clinical status and could be explained by airway closure at FRC, combined with an uneven distribution of pleural pressure.

The European respiratory journal. Supplement

BMJ Open Respiratory Research, 2015

Previous studies found larger lung volumes at school-age in formerly breastfed children, with som... more Previous studies found larger lung volumes at school-age in formerly breastfed children, with some studies suggesting an effect modification by maternal asthma. We wanted to explore this further in children who had undergone extensive lung function testing. The current study aimed to assess whether breastfeeding was associated with larger lung volumes and, if so, whether all compartments were affected. We also assessed association of breastfeeding with apparent diffusion coefficient (ADC), which measures freedom of gas diffusion in alveolar-acinar compartments and is a surrogate of alveolar dimensions. Additionally, we assessed whether these effects were modified by maternal asthma. We analysed data from 111 children and young adults aged 11-21 years, who had participated in detailed lung function testing, including spirometry, plethysmography and measurement of ADC of (3)Helium ((3)He) by MR. Information on breastfeeding came from questionnaires applied in early childhood (age 1-4 years). We determined the association between breastfeeding and these measurements using linear regression, controlling for potential confounders. We did not find significant evidence for an association between duration of breastfeeding and lung volumes or alveolar dimensions in the entire sample. In breastfed children of mothers with asthma, we observed larger lung volumes and larger average alveolar size than in non-breastfed children, but the differences did not reach significance levels. Confirmation of effects of breastfeeding on lung volumes would have important implications for public health. Further investigations with larger sample sizes are warranted.

Pediatric Pulmonology

Multi-center research studies that include pulmonary function as an objective outcome are increas... more Multi-center research studies that include pulmonary function as an objective outcome are increasingly important in pediatric respiratory medicine. The need for local controls rather than depending on published normative data for lung function remains debatable. To compare pulmonary function in childhood controls with no respiratory symptoms from three centers in the United Kingdom and ascertain the extent to which current reference equations are appropriate for this population. Spirometry, plethysmographic lung volumes, and specific airways resistance (sRaw) were measured within specialized pediatric laboratories in children from three geographical locations throughout the UK (London, Leicester, and Glasgow), using identical equipment, software and standard operating procedures. Results were compared between centers and in relation to recent or commonly used UK pediatric reference values. Pulmonary function was assessed in 94 healthy children (mean (SD) age: 7.7 (0.6) years; 88% wh...

Pediatrics, 2007

Extracorporeal membrane oxygenation has been shown to be effective in term neonates with severe b... more Extracorporeal membrane oxygenation has been shown to be effective in term neonates with severe but reversible lung disease within the context of randomized, controlled trials. Extracorporeal membrane oxygenation now has been open to a wider population of infants in the United Kingdom, and other treatments have become available. The population referred for extracorporeal membrane oxygenation, therefore, has changed. The aims of this study were to (1) compare respiratory outcomes of infants who received extracorporeal membrane oxygenation in recent years with those from 10 years ago and (2) determine whether respiratory outcome varied with diagnostic group. All infants who were referred to a single extracorporeal membrane oxygenation center and were <12 months old during a 7-year period were eligible. One year after extracorporeal membrane oxygenation, lung volume, airway conductance, maximum expiratory flow, and indices of tidal breathing were measured. A total of 106 infants (77...

The American review of respiratory disease, 1987

Functional residual capacity (FRC) was measured by the closed-circuit helium dilution method in 4... more Functional residual capacity (FRC) was measured by the closed-circuit helium dilution method in 41 supine healthy children 1 month to 8 yr of age. In 20 children, the measurement was carried out while they were awake, and in the others, who were less cooperative, testing was done during ketamine anesthesia before elective surgery. There was no significant difference in the FRC values between these groups, and they were subsequently analyzed as a single group. For males and females separately and combined, FRC correlated significantly with height, age, and weight, both with linear and nonlinear regression analyses. No significant difference between the sexes was found. The best correlation of FRC was with height; the linear equation being FRC (ml) = -457.3 + 8.8 X height (cm) (r2 = 0.662), and the nonlinear equation being FRC (ml) = 0.0052 X [height (cm)]2.44 (r2 = 0.827).

B96. NORMAL AND ABNORMAL LUNG GROWTH AND DEVELOPMENT, 2010

University of Leicester, Leicester, United Kingdom, University of Nottingham, Nottingham, United ... more University of Leicester, Leicester, United Kingdom, University of Nottingham, Nottingham, United Kingdom, University of Berne, Berne, 1 ... Corresponding author's email: mn87@le.ac.uk ... Rationale: Incidence of neonatal chronic lung disease (CLD) following extreme preterm ...

Respiratory medicine, 2004

Studies into the effects of salbutamol in the treatment of wheeze in infancy have been conflictin... more Studies into the effects of salbutamol in the treatment of wheeze in infancy have been conflicting, possibly due to differences in outcome variables. We aimed to assess the response to salbutamol using indices derived from passive and forced expiration. We recruited 39 infants who had a history of wheezing (mean age 43 weeks) and measured maximum flow at functional residual capacity (V'(max FRC)) by rapid thoracoabdominal compression (RTC), and forced expired volume at 0.4s (FEV0.4) using the raised-volume RTC technique (RV-RTC). We calculated passive compliance (C(rs)), resistance (R(rs)) and time constant (tau) from relaxed expirations that followed the augmented inspirations delivered during RV-RTC. Measurements were repeated after aerosol salbutamol (800 mcg). Data were obtained in 32 infants for V'(max FRC), 22 for FEV0.4 and 19 for passive mechanics. There were no mean changes in any index of forced expiration after salbutamol. Some individuals showed significant chang...

D16. CYSTIC FIBROSIS: BIOMARKERS, OUTCOME MEASURES, AND PATHOGENESIS, 2012

The European respiratory journal, Jan 8, 2015

Bioanalysis, 2013

In-community non-invasive identification of asthma-specific volatile organic compounds (VOCs) in ... more In-community non-invasive identification of asthma-specific volatile organic compounds (VOCs) in exhaled breath presents opportunities to characterize phenotypes, and monitor disease state and therapies. The feasibility of breath sampling with children and the preliminary identification of childhood asthma markers were studied. End-tidal exhaled breath was sampled (2.5 dm³) from 11 children with asthma and 12 healthy children with an adaptive breath sampler. VOCs were collected onto a Tenax®/Carbotrap hydrophobic adsorbent trap, and analyzed by GC-MS. Classification was by retention-index and mass spectra in a &amp;amp;amp;amp;amp;amp;amp;#39;breath matrix&amp;amp;amp;amp;amp;amp;amp;#39; followed by multivariate analysis. A panel of eight candidate markers (1-(methylsulfanyl)propane, ethylbenzene, 1,4-dichlorobenzene, 4-isopropenyl-1-methylcyclohexene, 2-octenal, octadecyne, 1-isopropyl-3-methylbenzene and 1,7-dimethylnaphtalene) were found to differentiate between the asthmatic and healthy children in the test cohort with complete separation by 2D principal components analysis (2D PCA). Furthermore, the breath sampling protocol was found to be acceptable to children and young people. This method was found to be acceptable for children, and healthy and asthmatic individuals were distinguished on the basis of eight VOCs at elevated levels in the breath of asthmatic children.

B61. PEDIATRIC ASTHMA, 2012