How can I differentiate between a COPD exacerbation and other respiratory conditions in a patient presenting with increased breathlessness?

To differentiate a COPD exacerbation from other respiratory conditions, look for features suggestive of an acute exacerbation, such as worsening breathlessness, increased sputum volume and purulence, cough, wheeze, fever without an obvious source, and recent upper respiratory tract infection, along with increased respiratory or heart rate (20% above baseline) ².

Assess for severity by checking vital signs, oxygen saturation, and clinical signs like cyanosis, peripheral oedema, or confusion, which may indicate a severe exacerbation requiring hospitalisation ².

Consider other causes such as myocardial infarction, pneumonia, pulmonary embolus, or worsening heart failure, especially if symptoms are atypical or do not respond to usual COPD management ².

Perform a thorough clinical assessment, including examination of the chest and vital signs, and consider investigations like ECG, chest X-ray, or blood tests to rule out alternative diagnoses ².

In summary, key differentiators include the pattern and progression of symptoms, associated signs, and response to initial treatment, with particular attention to features like fever, chest pain, or signs of cardiac or infectious causes ².