Dyspnoea DDx

Dyspnoea – Differential Diagnosis

Common causes

• Asthma
• COPD
• Bronchitis/RTI
• Anaemia
• Obesity

Must Not Miss

• Airway obstruction
  • Anaphylaxis
  • Foreign body
  • Epiglottitis
• Cardio- respiratory
  • Pneumonia
  • Pulmonary embolism
  • Pneumothorax
  • Myocardial Infarction
  • Heart failure
  • Arrhythmia
  • Pleural effusion
  • Tuberculosis
  • Lung cancer
• Diabetic ketoacidosis

Easily missed

• Medication
• Psychogenic (Hyperventilation)
• Obstructive sleep apnoea
• Pulmonary fibrosis
• Pulmonary hypertension
• Sarcoidosis
• Hyperthyroidism

Red flags

• Acute onset /severe dyspnoea
• Associated features
• Cyanosis
• Confusion
• Haemoptysis
• Chest pain
• Hypotension, sweating
• ‘Silent chest’
• Systemic symptoms (weight loss, night sweats, fever)

Investigations to consider

• FBC, CRP/ESR, D-dimers
• U+Es, LFTs, TFTs, Serum glucose
• BNP, Cardiac enzymes
• Pulse oximetry, ABGs
• PEFR, Spirometry
• Sputum analysis
• ECG
• CXR
• CT scan
• Echocardiography, 24 hour ECG
• V/Q scan
• Pulmonary angiography