Dyspnoea.

Question 1

Acute. (4)

Answer 1

Pulmonary embolism.
Pneumothorax.
Foreign body.
Anaphylaxis.

Question 2

Subacute. (4)

Answer 2

Cardiac failure (acute and chronic).
Asthma.
COPD.
Pneumonia.

Question 3

Chronic. (10)

Answer 3

Cardiac failure (acute and chronic). 
Asthma. 
COPD. 
Lung cancer. 
Pleural effusion. 
Fibrosing lung disease. 
Pulmonary hypertension. 
Anaemia. 
Thyrotoxicosis. 
Pulmonary embolism.