Modified hypoxic challenge testing in children needing nocturnal ventilation: An observational study

Abstract

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 SpO 2, 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-tofly" 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.

‘It gives me more freedom’: Family perspectives on travelling with children on nocturnal ventilation

“…In this paper, we illustrate and discuss the three themes that provide insight into family life related to travelling for children requiring nocturnal ventilation: insight into children's lives, travelling with your child and the meaning of travel, along with their associated sub‐themes (Figure 2). We have reported on the data related to participants' and families' experiences of taking part in the study in Riley et al (2023). In this paper, we describe the overarching themes, outlining each sub‐theme with illustrative quotations from the data.…”

“…The children's and their parents' articulated participation in air travel was meaningful in many ways but particularly as a symbol of equity of opportunity. Although wheelchair access remained a challenge for some, both via the testing chamber (Riley et al, 2023) and in accessing seats in an aircraft, participants perceived that health care professionals were advocating a broader approach to children's lives than previously by investigating this issue. This expansion of equality of opportunity resonated strongly with the children and parents in our study, indicating support for the participation in activities and travel Canadian children had access to in Seear et al (2016).…”

“…The children's and their parents' articulated participation in air travel was meaningful in many ways but particularly as a symbol of equity of opportunity. Although wheelchair access remained a challenge for some, both via the testing chamber (Riley et al, 2023) (Rosenbaum & Gorter, 2012).…”

“…As there is little evidence‐based guidance for children with neuromuscular or central hypoventilation conditions needing nocturnal ventilation and there are no systematic studies of these children's experience of travel, we aimed to evaluate (1) their experience of the modified HCT itself; (2) their experience of participating in research of this type; and (3) their general experience of travel, specifically air travel. We have previously reported on the physiological outcomes and the experiences of test participation and concluded that evaluating responses to patients' usual ventilation within a ‘fitness‐to‐fly’ assessment aids decision‐making when considering whether children who receive nocturnal ventilation can travel by air, as for some, using a ventilator reduces or avoids the need for supplemental oxygen (Riley et al, 2023).…”

ERS International Congress 2022: highlights from the Paediatrics Assembly

“…R iley et al . [ 4 ] assessed the response to low ambient oxygen (15%) using a hypoxic challenge test (HCT) in 20 children requiring nocturnal ventilatory support (10 with neuromuscular disease and 10 with congenital central hypoventilation): 13 out of 20 patients needed supplemental oxygen, and 11 out of 13 had normal saturations using their usual ventilator without supplemental oxygen. Transcutaneous carbon dioxide ( P tcCO 2 ) remained within normal range for all patients.…”