Hypoxic challenge test

What is a hypoxic challenge test? 

A hypoxic challenge test is a procedure performed to give us information about what might happen to your blood oxygen levels if you travel in an aeroplane. 

Why do I need to have this test? 

In an aircraft there is less oxygen available in the air. For people with a respiratory problem this can cause their oxygen levels to drop too low. This test will determine whether you need additional oxygen when you are in an aircraft. 

What happens during the test?

Before the test begins the Physiologist will explain the test to you in detail and will answer any questions that you may have. 

For the duration of the hypoxic challenge test you will be seated. A probe will be put on your finger. This will provide us with information about your blood oxygen levels. 

As part of the test it is also necessary to take several pinpricks of blood from your earlobe to provide further information about your blood oxygen levels. 

The test may take up to 90 minutes to complete. The length of the test may vary depending on your blood oxygen level. 

Important information

• Please continue to take all medications as normal.
• Please do not wear nail varnish to your appointment.
• You are advised not to book or pay for any flights until you have had the results of this test.
• It is very dangerous to go on a flight if you have been advised against this or to travel without oxygen if you have been advised to use it. You could experience serious breathing difficulties.

Thank you for your co-operation. This will assist us in obtaining accurate information and enable us to provide you with the most appropriate treatment.

Frequently asked questions

Will I experience any discomfort or side effects?

The only discomfort you may experience is a slight scratch on your ear when a pinprick of blood is taken. There are no known side effects associated with this test.

Is there a different test I could have?

There is no other test that would give us this information about your blood oxygen levels in a flight environment.

When will I be told the results of my test?

The Physiologist will provide information about the outcome of the test at your appointment. The report will be sent to the professional requesting the test. If you require paperwork to be completed for the airline this will need to be completed either by your Consultant or GP. If you require oxygen it will be your responsibility to organise this with the airline that you are travelling with.

What should I wear when I attend for my test?

You should wear normal comfortable clothing.

Reference

British Thoracic Society Standards of Care Committee (2011) BTS Clinical Statement on air travel for passengers with respiratory disease. London: British Thoracic Society.

© North Bristol NHS Trust. This edition published June 2024. Review due June 2027. NBT002290.