1303 - Clearing for Takeoff: High-Altitude Simulation Testing in a Medically Complex Rehabilitation Patient

An 81-year-old man with severe aortic stenosis, HFpEF, OSA on nocturnal BiPAP, hypertension, diabetes, and prior CABG was admitted with acute respiratory failure due to parainfluenza infection, multifocal pneumonia, and a presumed COPD exacerbation. He improved with antibiotics, steroids, and diuresis, then transferred to inpatient rehabilitation for deconditioning.

Because he planned to return home by commercial air travel, an initial HAST was performed. At simulated cabin altitude with 15% FiO₂, he maintained acceptable oxygenation at rest but desaturated to 86% with ambulation. Supplemental oxygen at 2 L/min via nasal cannula was recommended for exertion at altitude.

After several weeks of rehabilitation, repeat HAST prior to discharge showed marked improvement: SpO₂ ≥95% at rest and only 90% with ambulation. Based on these findings, pulmonology advised he could safely fly without in-flight oxygen if seated, with wheelchair assistance to limit exertion. The patient successfully traveled home without supplemental oxygen.

Discussions:

Commercial flights expose passengers to cabin pressures equivalent to ~8,000 feet, which can unmask hypoxemia in patients with underlying cardiopulmonary disease. High-altitude simulation testing (HAST) helps identify those at risk, but in rehabilitation, exertional capacity may be just as important as resting oxygenation. This case highlights that exertional desaturation may only be revealed through functional testing, even when resting oxygenation is adequate. The patient’s improved performance on repeat HAST after rehabilitation demonstrates how functional recovery can directly influence flight clearance and discharge planning. Rehabilitation physicians are uniquely positioned to be able to integrate these types of physiologic and functional assessments into their transition-of-care planning.

Conclusions:

HAST, combined with functional evaluation, provides individualized recommendations for patients with complex cardiopulmonary disease, ensuring safe air travel and optimized discharge planning