Hypoxia in flight simulation in obese patients with or without COPD

Introduction: Passengers traveling in an aircraft are exposed to decreased atmospheric and O2 partial pressure, leading to reduced blood O2 saturation (SpO2). COPD patients, depending on disease severity, are highly susceptible for resulting hypoxia due to gas exchange impairments. Since concomitant obesity (BMI≥30 kg/m²) may be associated with ventilation-perfusion mismatch, this could lead to further aggravation of hypoxia. We asked how SpO2 is influenced in simulated flight in obese COPD patients compared with healthy obese. Methods: 19 obese participants (8 healthy, 11 COPD patients) were exposed to simulated flight conditions using hypoxia altitude simulation test (HAST, inhaled 15.1% O 2 ) and hypobaric chamber test (760 mbar, HCT). Lowest stable SpO2 was measured. Results: HAST- and HCT-SpO2 values of COPD patients were mostly Discussion: Most obese COPD patients experience relevant hypoxia in simulated flight supporting the demand for pre-flight testing to assess ability to fly and recommend O2 supplementation where necessary. Obesity alone without significant pulmonary disease does not result in relevant SpO2 decrease (