Air travel for some adult patients with pulmonary diseases may be challenging, so having proactive discussions with your patients is key.

“Without appropriate preparation and intervention, patients may experience significant hypoxemia in flight, which can lead to shortness of breath, light headedness and confusion, as well as cardiac problems,” said Andrew Berman, MD, a pulmonologist and a professor of medicine, New Jersey Medical School, Rutgers University, in Newark, New Jersey.

The Implications of Cabin Pressure While Flying

Airplane cabin pressure at cruising altitudes is similar to an altitude of around 8000 feet, the height of many mountains in Colorado and the Canadian Rockies, where the inspired oxygen concentration is close to 15%, Berman said.

“At this pressure, the oxyhemoglobin dissociation curve remains above 90% for the average healthy person, but not for those with severe respiratory conditions, even when in a stable state,” he added.

Among the respiratory conditions that air travel can pose the greatest threat are chronic obstructive pulmonary disease and pulmonary fibrosis, where oxygen may be reduced at baseline and fall well below 90% at cruising altitude. “Patients with these respiratory conditions which are not controlled should not fly,” cautioned Berman.

A study revealed that it’s recommended that such patients refrain from flying until the patient has returned to their baseline and have discussed their travel plans with their medical provider, with some advocating to wait 6 weeks before air travel is considered.

For patients who are at their respiratory baseline but are dependent on supplemental oxygen, close coordination of their travel plans with their primary care provider is recommended.

“Certainly, any patient already on oxygen should plan to travel with oxygen, though the flow may need to be increased,” Berman said.

For patients already on > 4 lpm at rest, portable oxygen concentrators (POCs) may not be able to deliver an adequate flow of oxygen during air flight, he said, and should consider alternative modes of transportation. Furthermore, patients not on home oxygen with a resting pulse oximetry reading of > 95% generally do not need in-flight oxygen; however, those with a resting oxygen saturation < 95% should undergo a 6 minute walk test and those whose oxygen saturation falls below 84% during testing should receive in-flight oxygen, usually at 2 lpm, said the pulmonologist.

For patients whose oxygen saturation is > 84% on a 6 minute walk test, the British Thoracic Society recommends a high-altitude simulation test (also known as a hypoxic challenge test) to determine the need and flow rate of oxygen in flight.

During this test, a patient breathes air that has the same amount of oxygen as an airplane does when flying at cruising altitude. “A low oxygen level after 20 minutes would warrant a prescription for supplemental oxygen when flying,” affirmed Berman. “Portable oxygen concentrators are the only form of oxygen permitted on airplanes, though policies differ among airlines, so patients must coordinate with their individual airline each time they fly to find out if their particular unit is acceptable and if there are any restrictions.”

What Type of Documentation Will Patients Require?

Federation Aviation Administration approved devices all have a permanent external label in red lettering stating it is an acceptable device for air flight. “A letter or certificate from medical professional will be needed, and must be renewed after 1 year, and sometimes earlier depending on the airline,” Berman said. Your patients should also be advised that some airlines require their own form to be completed.

Berman recommends sharing these crucial factors with patients who are traveling with POCs.

• While access to power at the gate and onboard has become common lately, seat outlets do not always work, and older planes may not have power outlets. Remind patients that they should have ample battery power to last the entire flight as well as any time delay.
• Nonstop flights are recommended and getting to the airport with extra time.
• Making use of airport assistance, and early boarding, when possible.
• Many airlines and patient forums recommend battery life of 1 and 1/2 times the number of hours of flight time.
• Patients should be aware that many airlines require passengers using a POC to sit in a window seat; and that seating in an emergency row or bulkhead row is not allowed.
• If continued oxygen is needed after the flight, then arrangements need to be made at the destination, especially if it is one of high altitude.

Reassure Your Patients to Promote Safety

Trishul Siddharthan, MD, a pulmonary and critical care physician and associate professor of medicine at Miller School of Medicine, University of Miami, Miami, agreed that patients with severe pulmonary disease should exercise caution when considering air travel. He offered these additional guidelines:

• Consult with your patient. Discuss travel plans with your patient and get clearances.
• Medication discussions. “Do not change medications within 2 weeks of long-distance travel,” said Siddharthan.
• Reiterate oxygen requirements. “Instruct patients to look into in-flight oxygen, if necessary as not all airlines permit in-flight nebulizer treatments,” he stated.
• Have patients carry a record of pulmonary functions and oxygen needs. “Patients should carry or store a record of baseline pulmonary function and oxygen saturations for immediate access during travel,” said Siddharthan.