Some patients with chronic obstructive pulmonary disease (COPD) need supplementary oxygen during air travel. Guidelines issued by The British Thoracic Society (BTS) for pre-flight evaluation do not discriminate sufficiently between those who need supplementary oxygen during flight, and those who can do without. Previous studies have indicated that decreasing hemoglobin oxygen saturation during exercise may predict in-flight hypoxemia. The objective of the present study is to examine if adding exercise oxygen desaturation to the BTS algorithm will better predict requirements for in-flight supplementary oxygen.

The British Thoracic Society (BTS) guidelines on pre-flight evaluation for patients with chronic respiratory disease is based on an algorithm where arterial oxygen saturation is the discriminating factor. It has recently been shown that this algorithm does not discriminate sufficiently between patients who need pre-flight evaluation and maybe supplementary oxygen during air travel, and those who can travel by air without supplemental oxygen or further evaluation. Studies have also shown that exercise desaturation may predict in-flight hypoxemia. The objective of the present study is to examine if inclusion of arterial oxygen saturation measured by pulseoximetry during exercise in the BTS algorithm, will increase the sensitivity and specificity of the BTS pre-flight evaluation guidelines.The study also include questionnaires on symptoms during air travel carried out before ande after the pre-flight evaluation.

Inclusion Criteria:

• patients with COPD who have performed a hypoxia altitude simulation test
• able to perform the 6-minute walking test

Exclusion Criteria:

• unstable angina
• uncontrolled hypertension
• uncontrolled arrythmia
• patients with long-term oxygen treatment

COPD patients