HF 6383

High Altitude Simulation Test (HAST)

What is a high altitude simulation test (HAST)?

This test will tell your doctor how much extra oxygen, if any, you may need when flying or traveling to high altitudes. You may need more oxygen if you have lung disease.

How do I prepare for this test?

  • No smoking or breathing in secondhand smoke before the test.

  • Remove any fingernail polish.

  • No heavy exercise before the test.

What happens during the test?

For this test you will be in a reclined chair. A nasal canula will be placed in your nose and a mask will be placed over your mouth and nose. There will be a constant flow of air released into the mask. This will be like the oxygen level during air travel.

A small sensor on your finger will measure your oxygen level. If your oxygen level decreases to a certain level, we may draw a small sample of blood. The blood sample tells us the oxygen level in your blood. After the blood draw, we may give you extra oxygen until your oxygen level is at the desired level.

What do I need to do after the test?

You should be able to do your normal routine after the test. Your health care provider will talk with you about your test results when the final report is ready.

When to Call

If you have any questions or concerns before the test, please call.

Who to Call

UW Pulmonary Function Lab

(608) 263-7000 or (800) 323-8942

If you are a patient receiving care at UnityPoint – Meriter, Swedish American or a health system outside of UW Health, please use the phone numbers provided in your discharge instructions for any questions or concerns.