Pleural effusion

Question 1

Light’s criteria

Answer 1

Transudative:

• Increased hydrostatic pressure/decreased colloid osmotic pressure
• Systemic factors - CHF, CKD, cirrhosis, atelectasis
• Increased proteins and lactate dehydrogenase (LDH)

Exudative:

• Inflammation
• Local factors - pneumonia, PE, cancer, TB, pancreatitis, sarcoidosis

Question 2

Symptoms of pleural effusion

Answer 2

• Dyspnoea
• Pleuritic chest pain
• Cough

Question 3

Signs of pleural effusion

Answer 3

• Dull percussion
• Decreased breath sounds
• Decreased vocal resonance
• Contralateral tracheal deviation
• Friction rub

Question 4

Investigations for pleural effusion

Answer 4

• Laboratory:
  
  • Pleural and serum proteins and LDH
  • Pleural and serum RBC, WBC, cytology, culture pH and glucose
• Imaging:
  
  • CXR
  • CT
• Other:
  
  • Thoracentesis ± US

Question 5

Management of pleural effusion

Answer 5

• Treat underlying cause (e.g. diuretics, antibiotics)
• Therapeutic thoracentesis