{
  "abstract": "Introduction In 2022 the British Thoracic Society (BTS) published updated guidance (Coker RK, et al. Thorax 2022;0:1–22) on air travel for patients with respiratory conditions. These revised referral criteria for hypoxic challenge test (HCT), advising that patients on long term supplemental oxygen (O 2) should ideally have their in-flight O2 flow determined by HCT.Aim To assess if performing HCT for patients on long-term O 2 changed management beyond previous guidance (Ahmedzai, S et al. Thorax 2011;66: i1ei30) which recommended doubling baseline flow during flight.Method All HCTs performed between March 2022 and December 2024 were reviewed. Patients were included if they were current users of O 2 (including those in nocturnal only O2). Children in nocturnal only O2 therapy started their test in air, provided baseline SpO2 was greater than 92%. All other children started their test at their prescribed daytime flow. During the test the O2 flow was increased in steps of 1 L/min, with a starting point of 1 L/min as this is the lowest flow widely available during flight.Results Three hundred and fifty-two HCTs were reviewed and 18 patients (11 female, mean±SD age 7.17±5.84 yrs) met the criteria for inclusion. Thirteen out of 18 were in nocturnal O 2 therapy only. Two children had their baseline flow doubled during HCT. One had their baseline flow more than doubled, from 0.2 L/min to 2 L/min. Four children with starting flow <0.5 L/min had their flow increased to 1 L/min. Four children did not require any change in their O2 flow. Five children in nocturnal only O2 therapy and two with O2 use only when unwell did not require O2 during the test.Conclusions In this study, all children in 24-hr O 2 did not require any change in their O2 flow during HCT. For children in nocturnal only O2 the results were variable. Almost half of these children did not require O2 therapy during HCT, creating uncertainty as to whether O2 should be prescribed during flight. It is still uncertain whether the new guidance provides useful additional clinical information.",
  "authors": [
    {
      "affiliations": [
        "Great Ormond Street Hospital, London, UK"
      ],
      "name": "Kirstie Rogers"
    },
    {
      "affiliations": [
        "Great Ormond Street Hospital, London, UK"
      ],
      "name": "Emma Fettes"
    },
    {
      "affiliations": [
        "Great Ormond Street Hospital, London, UK"
      ],
      "name": "Paul Aurora"
    }
  ],
  "title": "P49 Impact of new hypoxic challenge testing guidelines for children on long term supplemental oxygen",
  "uid": "ded90eb4-c4bb-5cbe-92a0-f49c4542ab27"
}