Children with a history of bronchopulmonary dysplasia (BPD) may be at risk of hypoxaemia at altitude, such as during air travel. We have performed preflight hypoxic challenge testing (HCT) since ...2006, incorporating British Thoracic Society (BTS) guidance since 2011, to determine which children may require oxygen during air travel.
We aimed to compare the outcome of HCTs in children with a history of BPD who met the 2011 BTS criteria and those who did not and, in addition to this, to interrogate the data for factors that may predict the outcome of HCT in this population.
We performed a retrospective analysis of data from HCTs of children with a history of BPD referred 2006-2020. Cases were excluded if the patient had a respiratory comorbidity, was still on oxygen therapy, if the test was a repeat or if the clinical record was incomplete. Descriptive and univariate analysis of the data was performed, and a binary logistic regression model was fitted.
There were 79 HCTs, of which 24/79 (30%) did not meet BTS 2011 guidelines referral criteria. The analysis showed a greater proportion of desaturation in the group that did
meet criteria: 46% vs 27% (no statistical significance). Baseline oxygen saturations were higher in those who did not require oxygen during HCT and this variable was significant when adjusted for confounders.
This study found that the current criteria for referral for preflight testing may incorrectly identify those most at risk and highlights the need for further investigation to ensure those most at risk are being assessed prior to air travel.
Abstract The multiple breath washout (MBW) test is widely reported in the context of Lung Clearance Index (LCI). LCI reflects global ventilation inhomogeneity but does not provide information ...regarding the localization of disease along the respiratory tree. The MBW‐derived normalized phase III slope (S nIII ) indices (S cond and S acin ), instead, can distinguish between convective‐dependent and diffusion‐convection‐dependent ventilation inhomogeneity considered to occur within the conductive and acinar airways, respectively. In cystic fibrosis, S cond tends to become abnormal even earlier than LCI and spirometry. The value of S cond and S acin in clinical practice has been recently explored in other respiratory conditions, including asthma, primary ciliary dyskinesia, bronchopulmonary dysplasia, bronchiolitis obliterans, and sickle cell disease. In this narrative review we offer an overview on the theoretical background, potentialities, and limitations of S nIII analysis in children, including challenges and feasibility aspects. Moreover, we summarize current evidence on the use of S nIII ‐derived indices across different groups of pediatric chronic respiratory disease and we highlight the gaps in knowledge that need to be addressed in future studies.
Introduction
The coronavirus disease 2019 (COVID‐19) pandemic has accelerated the move towards home spirometry monitoring, including in children. The aim of this study is to determine whether the ...remote supervision of spirometry by a physiologist improves the technical quality and failure rate of the maneuvers.
Method
Children with cystic fibrosis who had been provided with NuvoAir home spirometers were randomly allocated to either supervised or unsupervised home spirometry following a detailed training session. Home spirometry was performed every 2 weeks for 12 weeks. Tests were assigned a quality factor (QF) using our laboratory grading system as per American Thoracic Society/European Respiratory Society standards, with tests marked from A to D, or Fail. In our laboratory, we aim for QF A in all spirometry tests, but report results of QF B or C with a cautionary note. QF A was, therefore, the primary outcome, and QF A–C, the secondary outcome.
Results
Sixty‐one patients were enrolled; 166 measurements were obtained in the supervised group, and 153 in the unsupervised group. Significantly more measurements achieved QF A in the supervised compared to unsupervised group (89% vs. 74%; p = <0.001), while proportions reaching Grade A–C were similar (99% vs. 95%; p = 0.1). All significant declines in spirometry results had a clinical rather than technical reason. Family/patient feedback for both arms was very positive.
Conclusion
These results suggest that home spirometry in children should ideally be remotely supervised by a physiologist, but acceptable results can be obtained if resources do not allow this, provided that training is delivered and results monitored according to our protocol.
Background
Guidelines for air passengers with respiratory disease focus on primary lung pathology. Little evidence exists to guide professionals advising children needing ventilatory support because ...of neuromuscular or central hypoventilation conditions; these children might risk hypoxia and hypercapnia if unable to mount an adequate hyperventilation response.
Objective
This study assessed the response to low ambient oxygen using a modified hypoxic challenge test. In addition to measuring pulse oximetry and response to supplementary oxygen, we also measured transcutaneous carbon dioxide and response to ventilatory support.
Methods
Twenty children on nocturnal ventilatory support aged 1.6−18 years were recruited in a pragmatic sample from outpatient clinics; 10 with neuromuscular weakness and 10 with central hypoventilation. Participants underwent a two‐stage, modified hypoxic challenge test; a conventional stage, where oxygen alone was titrated according to SpO2, and a new stage, where participants used their routine ventilatory support with oxygen titrated if needed. Participants were interviewed to understand their experiences of testing and of air travel.
Results
Thirteen participants needed supplemental oxygen during the conventional stage, but only two did when using ventilatory support. Transcutaneous carbon dioxide remained within normal range for all participants, on or off ventilatory support. Whilst some participants found testing challenging, participants generally reported both testing and air travel to be valuable.
Conclusions
Evaluating response to patients' usual ventilation through “fitness‐to‐fly” assessment aids decision making when considering whether children who receive nocturnal ventilation can travel by air, since for some using a ventilator reduces or avoids the need for supplemental oxygen.
Background
Children with neuromuscular weakness or central hypoventilation often require nocturnal ventilation. Children with these conditions are living longer and the numbers of children affected ...are increasing. The challenges associated with managing ventilation at home have been documented; however, there has been limited investigation into accessing wider experiences such as travel. Air travel, in particular, may be considered challenging for children with these conditions because oxygen levels are lower in airplane cabins than at sea levels.
Objective
We sought to understand experiences of and attitudes towards travel amongst families of children using nocturnal ventilation for neuromuscular weakness or central hypoventilation.
Methods
Two semi‐structured interviews were conducted amongst participants enrolled in a trial of a new pre‐flight assessment of their tolerance of reduced oxygen levels during flight (known as a hypoxic challenge test). Children participating in the trial were aged 19 months to 18 years. Parents were interviewed and provided proxy views for younger children, and older children were encouraged to present their own views during these interviews. One interview was conducted immediately after the assessment, and a second 3 months later. Data were analysed utilising the framework approach to thematic analysis.
Results
Seventeen families participated in the first interview with 14 of these families completing the follow‐up interview. Three further families participated in the follow‐up interview only. Here, we report three themes relating to participant experience of travel and how this is impacted by their condition. The three themes and their sub‐themes were (1) insight into children's lives: hospital attendances, gaining knowledge and confidence, and child as a person; (2) travelling with your child: planes, trains and automobiles, rules of air travel, and uncertainty; and (3) the meaning of travel: normalisation, connection to extended family, expanded experiences, and freedom and equality.
Conclusions
This population of children and their families aspire to travel but face challenges from clinical and social barriers. It is essential that we further our understanding of the physiological, social and cultural aspects of their experience to facilitate their access to broadened life experiences.
Introduction/Aims
Mutations amenable to skipping of specific exons have been associated with different motor progression in Duchenne muscular dystrophy (DMD). Less is known about their association ...with long‐term respiratory function. In this study we investigated the features of respiratory progression in four DMD genotypes relevant in ongoing exon‐skipping therapeutic strategies.
Methods
This was a retrospective longitudinal study including DMD children followed by the UK NorthStar Network and international AFM Network centers (May 2003 to October 2020). We included boys amenable to skip exons 44, 45, 51, or 53, who were older than 5 years of age and ambulant at first recorded visit. Subjects who were corticosteroid‐naive or enrolled in interventional clinical trials were excluded. The progression of respiratory function (absolute forced vital capacity FVC and calculated as percent predicted FVC%) was compared across the four subgroups (skip44, skip45, skip51, skip53).
Results
We included 142 boys in the study. Mean (standard deviation) age at first visit was 8.6 (2.5) years. Median follow‐up was 3 (range, 0.3‐8.3) years. In skip45 and skip51, FVC% declined linearly from the first recorded visit. From the age of 9 years, FVC% declined linearly in all genotypes. Skip44 had the slowest (2.7%/year) and skip51 the fastest (5.9%/year) annual FVC% decline. The absolute FVC increased progressively in skip44, skip45, and skip51. In skip53, FVC started declining from 14 years of age.
Discussion
The progression of respiratory dysfunction follows different patterns for specific genotype categories. This information is valuable for prognosis and for the evaluation of exon‐skipping therapies.
PDF
