Dyspnoea

Airways disease Chronic bronchitis and emphysema

Asthma

Bronchiectasis

Cystic fibrosis

Laryngeal or pharyngeal tumour

Bilateral cord palsy

Tracheal obstruction or stenosis

Tracheomalacia

Crico-arytenoid rheumatoid arthritis

Parenchymal disease Pneumonia

Allergic alveolitis

Sarcoidosis

Fibrosis and diffuse alveolitis

Diffuse infections

Respiratory distress syndrome

Infiltrative and metastatic tumour

Pneumothorax

Pneumoconiosis

Pulmonary circulation Pulmonary embolism

Chronic thromboembolic pulmonary hypertension

Pulmonary arteriovenous malformation

Pulmonary arteritis

Chest wall and pleura Effusion or massive ascites

Pleural tumour

Fractured ribs

Ankylosing spondylitis

Kyphoscoliosis

Neuromuscular diseases

Bilateral diaphragmatic palsies

Cardiac

LVF, Mitral valve disease, Cardiomyopathy

Pericardial effusion or constrictive pericarditis

Intracardiac shunt

Anaemia

Non-cardiorespiratory

Psychogenic

Acidosis (compensatory respiratory acidosis)

Hypothalamic lesions