Mease Countryside Hospital, Safety Harbor, Fla, now now offers the High Altitude Simulation Test, or HAST, to its patients, according to the hospital. The test helps identify which patients will require additional oxygen when they travel by plane and, if so, how much they’ll need.

“With the High Altitude Simulation Test, we can mimic the air someone would breathe on an airplane,” said Robert Stein, MD, pulmonologist and medical director of Respiratory Care Services at Mease hospitals. “When someone has this test done, we are able to carefully measure how they respond to the change in altitude. This tells us if they need extra oxygen when they fly, and if they do, exactly how much is needed.”

Planes are pressurized to between 8,000-10,000 feet, though most flights cruise at between 30,000 feet and 40,000 feet; at sea level, there is 21% oxygen; at 8,000 to 10,000 feet, 15% oxygen, according to background information provided by the hospital. Patients with chronic lung diseases and respiratory conditions are not always able to adequately compensate for the decrease in available oxygen.

The HAST, which lasts about 20 minutes, simulates the air a patient would breathe on an airplane pressurized to 9,000 feet by providing a mix of 15% oxygen with balanced nitrogen, which has been specially created for BayCare Health System. A licensed respiratory therapist monitors the patient’s vital signs, including oxygen levels, during the test.

“Once your physician knows the appropriate amount of oxygen a patient will need when flying on an airplane, he or she can write a prescription so the patient can work with their airline to ensure that they will have the correct amount of oxygen for their flight” said Stephen Brown, M.D., a pulmonologist and co-director of Respiratory Care Services at the Mease hospitals.