Hypoxic challenge test

Aircraft cabins are pressurised to between 5,000 to 8,000 feet, which means that the partial pressure of oxygen inside the aircraft is lower than what we breathe at sea level.

As a result of the lower oxygen levels in the aircraft cabin, most passengers will experience a small decrease in oxygen saturation – the amount of oxygen circulating in the body.

This is normally tolerated well in healthy individuals. People with cardiac and respiratory problems however, may require additional oxygen for the flight.

The hypoxic challenge test will help evaluate how well your child will tolerate the reduced oxygen levels in the aeroplane.

The hypoxic challenge test takes place in a large cabin that simulates being in an aircraft. The child sits inside the cabin for a set amount of time usually 20 minutes but in some patients who require additional monitoring this will be longer. To monitor oxygen saturation levels a pulse oximeter will be attached to your child's finger or toe. The oximeter sensor uses a painless wrap which uses light to measure oxygen levels.

Your child can take toys or a personal device for use whilst inside the cabin to keep them amused throughout the test (the department has patient iPads available for use if required). Parents can sit inside with younger children but will need to wear a pulse oximetry probe also.

Whilst inside the cabin babies can be bottle-fed or breast-fed as required.

A nasal cannula will be attached at the beginning of the test, to provide oxygen during the test, If required.

Some patients who already have medical devices for example non-invasive ventilators (BPAP machine) may have a modified hypoxic challenge test. During the modified test the patient will also be monitored whilst wearing their medical device. For these tests parents/guardians will be notified to bring the device with them to the appointment.

The report will be uploaded onto your child’s electronic patient record system for the doctor to view.

The appointment takes approximately 60 minutes but some tests may require longer if additional monitoring is needed.

Any medical equipment that your child requires e.g. suction equipment. Please bring along a favourite toy, book or electronic game which can help as a distraction during the test.

It can get hot inside the cabin, so if you need to sit inside the cabin with your child, you may wish to wear light clothing.

Please note, the person accompanying your child for the test should have ‘Parental Responsibility’ for them. Parental Responsibility refers to the individual who has legal rights, responsibilities, duties, power and authority to make decisions for a child. If the person bringing your child does not have Parental Responsibility, we may have to cancel the test.