Episodic hypoxemia in an airline passenger with chronic respiratory failure on supplemental oxygen.

Assessing the requirements for in-flight oxygen in passengers with pulmonary limitations can be a challenging task for clinicians. Aeromedical guidelines are available to help identify passengers that may require oxygen in flight. However, little is known about the actual in-flight response to passengers on oxygen. We measured the oxygen response (pulse oximetry) of a 67-yr-old female patient with chronic respiratory failure during a trans-Tasman flight (duration 170 min). This patient was assessed at the respiratory clinic before her journey and resting PaO 2 (57 mmHg) indicated the requirement for in-flight oxygen. Bottled oxygen delivered at 2 L "min -1 via nasal cannula was prescribed for her journey. Preflight SpO 2 without supplemental oxygen was 92%. Mean in-flight SpO 2 was well maintained at 93% while on oxygen at rest. There were four significant hypoxic events, which included light physical activity while on oxygen (three events; SpO 2 to 84%) and a visit to the lavatory (off oxygen; SpO 2 to 70%). Dyspnea and dizziness were reported during the lavatory visit. This case illustrates the importance of a preflight medical screening for passengers considered at risk during air travel and provides insight into the response of oxygen supplementation during flight.