A High Altitude Simulation Test (HAST) is a lung function test specifically designed to assess an individual's fitness to fly with breathlessness or underlying lung disease.
During this test, we are able to simulate the low oxygen environment experienced while flying and measures any drops in oxygen levels while sitting and standing. If oxygen levels fall below 85%, in-flight oxygen may be recommended.
We can then determine whether oxygen will be required to be safe at altitude and if so, how much each individual needs.
Fitness to Fly
For many people with lung conditions, the low oxygen and low pressure environment of the cabin can prove to be very demanding on their cardiac and respiratory systems.
All airlines are required to maintain at least 75% of the air pressure at sea level. This lower air pressure equates to reduced oxygen levels. The body increases its breathing rate to counter this reduction in oxygen. A healthy individual could expect to see their oxygen saturations drop to 5% of normal. People with lung problems however, can experience a sharp decrease in oxygen levels especially while performing light exercise (such as standing and sitting) and therefore may require in-flight oxygen.
Tips for the traveller
Holidays are generally fun events. However careful planning is required to prevent the onset of respiratory exacerbations or to prevent the worsening of an already existing respiratory condition.
- Buy a flexible ticket and ensure you have adequate travel insurance
- Take all of your medical documentation with you
- Arrange your oxygen (if required) well in advance
- Request a seat near the bathroom
- Take suitcases with wheels