Abstract
Bronchoscopy was performed on 227 patients in each of whom dyspnoea was a symptom. The cause of the dyspnoea was a malignant tumour in 38 % of the cases, a bronehopulmonary infection in 24 %, and a foreign body in 9%. In 11% no aetiologic factor could be demonstrated. The causes and mechanism of origin of dyspnoea are discussed.