Flying with respiratory disease.

Patients with respiratory diseases may be at risk during flight because at cruising altitude an important hypobaric hypoxia may occur. The only absolute contraindications to flying in these patients are pneumothorax, bronchogenic cyst and severe pulmonary hypertension. In order to evaluate the risks related to air travel in patients with respiratory diseases, an evaluation of their fitness to fly, including the hypoxia altitude simulation test, is required. The fitness to fly evaluation can identify patients requiring supplemental oxygen during flight which is provided by most airlines when prescribed by the passenger's physician. This review deals with the cardiorespiratory effects of flight, the risks associated with respiratory diseases during air travel and the procedures to follow in order to assess fitness to fly in patients with respiratory disorders.