'Fitness To Fly' Tests In Children With Type II Respiratory Failure

Study Overview
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Brief Summary
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The conventional hypoxic challenge test might not predict 'fitness-to-fly' equally well in all patients. Patients at risk of hypercapnia with supplemental oxygen are not well studied. Th investigators will study children who have either neuromuscular weakness or central hypoventilation and who require nocturnal or intermittent daytime ventilator support. The study also aims to assess feasibility of a randomised controlled trial (RCT) comparing the standard hypoxic standard test to a modified test designed to better suit children with type two respiratory failure.

Detailed Description
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This study will assess feasibility of pulse oximetry (SpO2), end tidal carbon dioxide (ETCO2) and transcutaneous carbon dioxide partial pressure (TcCO2) measurement during a modified Hypoxic challenge test (HCT) in 12 children with neuromuscular weakness and 12 with central hypoventilation.

Official Title
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'Fitness To Fly' Testing In Children With Neuromuscular Weakness Or Central Hypoventilation: A Feasibility Study

Conditions
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Neuromuscular Diseases, Central Hypoventilation

Intervention / Treatment
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* Diagnostic Test: Hypoxic challenge test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ≤18 years Neuromuscular weakness or central hypoventilation Established nocturnal or intermittent daytime ventilatory support Exclusion Criteria: Unable to sit in the plethysmograph Cardiac anomaly with right-to-left shunt

Ages Eligible for Study
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Minimum Age: 0 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Participants randomised to uniform balanced crossover (new/old or old/new hypoxic challenge test components).
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: new/old HCT component order<br>new/old hypoxic challenge test (HCT) component order Where the new test uses pulse oximetry and transcutaneous CO2 monitoring to guide use of ventilatory support and if necessary supplementary oxygen and the old test uses pulse oximetry to titrate supplementary oxygen. | Diagnostic Test: Hypoxic challenge test<br>* Physiological response to 15% ambient oxygen monitored.<br>|
| Other: old/new HCT component order<br>old/new hypoxic challenge test (HCT) component order Where the old test uses pulse oximetry to titrate supplementary oxygen and the new test uses pulse oximetry and transcutaneous CO2 monitoring to guide use of ventilatory support and if necessary supplementary oxygen. | Diagnostic Test: Hypoxic challenge test<br>* Physiological response to 15% ambient oxygen monitored.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| proof of concept outcome 1 | number of children/infants with SpO2 <90/85% | during hypoxic challenge test | 
| proof of concept outcome 2 | number of children with >15 mmHg rise in TcCO2/EtCO2 | during hypoxic challenge test | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Feasibility outcome 1: recruitment rate | recruitment rate | one year | 
| Feasibility outcome 2: protocol completion rate | protocol completion rate | one year |