High Altitude Simulation Test

Your doctor has requested that you perform a high altitude simulation test. This test is often performed if you plan on flying or travelling.

During the High Altitude Simulation Test (HAST) you will breathe through a mask for about 20-25 minutes. The mask will contain air that has the same amount of oxygen in it that the air in a commercial aircraft has in it at its highest flight level. During the test you will have a probe on your finger that will measure the amount of oxygen in your blood. You may be asked to do a small amount of exercise at the end of your test (such as sitting and standing for one minute) so you may wish to wear comfortable clothes and shoes.

Please tell staff in the laboratory if you have recently experienced any of the following recently:

• Coughing up blood
• Collapsed lung
• An unstable heart condition
• A heart attack in the last month
• Blood clots in the lung
• Chest, stomach or brain aneurysms
• Recent eye surgery
• Recent chest or stomach surgery
• Chest or abdominal pain of any cause
• Nausea or vomiting

The tests take approximately 45 minutes.