The Hypoxic Challenge Test is designed to determine whether you will need supplemental oxygen to
fly. This is necessary because on an aeroplane the pressurised cabin reduces the level of oxygen in
the air from 21% to 15%, which can mean some patients with lung conditions require extra oxygen
to fly safely.

What is involved?

Before the test starts we will take a small amount of blood from your wrist. During the test you will
be sitting down, you will breathe a reduced oxygen mixture using a facemask which will simulate the
conditions on a plane. Your oxygen levels and heart rate will be monitored for the next 20 minutes.

At the end of the test, a second blood sample will be taken.

If your oxygen levels decrease during the test, it may be necessary for the respiratory physiologist to
add extra oxygen to see if your oxygen levels go back to normal.

What happens after the test?

After the test your consultant will review the results and decide whether you will need supplemental oxygen when flying.

If supplemental oxygen is required your consultant will write a letter which can be used as evidence for your airline. Please note some airlines may require their own forms to be completed by your doctor. Please check the individual airlines policy about travelling with oxygen before booking to avoid disappointment.