Pleural effusion is the abnormal accumulation of fluid in the pleural space, categorized as transudative or exudative based on its underlying mechanisms. Diagnosis involves clinical examination, imaging, and pleural fluid analysis, including tests for cell count, protein levels, and various cultures. Treatment varies depending on the cause and may include therapeutic thoracentesis, drainage through inter-costal tubes, or pleurodesis.

1. Pleural Effusion
Dr P Mayurathan
MBBS (Jaffna), MD in Medicine (Col), MRCP (UK), FRCP (Lond), FRCP (Edin)
Senior Lecturer in Medicine, FHCS
Honorary Consultant Physician, THB

2. Pleural Effusion
• Abnormally excessive fluid accumulation in the pleural
space
• Due to the imbalance between formation and absorption
of pleural fluid
• In response to injury, inflammation or both locally and
systemically

3. Pleural Effusion

5. • Normal pleural fluid amount is 10 – 15 ml
• More than 500ml of pleural fluid is necessary to detect by
clinical examination
• More than 300ml of pleural fluid could be detected by
CXR in erect position. But lateral decubitus CXR can detect
even 50 ml
• But ultrasound scan could detect if more than 150ml
Pleural Effusion

6. Pathophysiology of Pleural Effusion
• Due to
– Increased capillary hydrostatic pressure
– Reduced capillary oncotic pressure
– Increased capillary permeability -
Transudative
Exudative

7. Pathophysiology of Exudative Pleural Effusion
• Increased capillary permeability
– Migration of inflammatory cells (neutrophils, lymphocytes and
eosinophils) into pleural space
• Process mediated by many inflammatory cytokines such as
– Interlukins: IL-1, IL-6, IL-8, TNF-α and Platelet activating factor
(by mesothelial cells)
• Neutrophils activate the coagulation cascade and cause
procoagulant activity and decrease fibrinolysis
• All leads to increase levels of of proteins and Lactate Dehydrogenase
(LDH) and reduction in pH and glucose levels

8. • It could be unilateral or bilateral
1. Based on the mechanism and type of pleural effusion
– Transudative
– Exudative
2. Based on the location of pleural effusion
– Apical
– Inter-lober
– Sub-pulmonic
– Mediastinal
3. Based on the type of pleural effusion formed
– Hydrothorax
– Haemothorax
– Chylothorax
– Empyema
Classification of Pleural Effusion
most important
classification

9. Causes of Pleural effusions

10. History
• SOB
• Pleuritic chest pain
• Cough
• Fever
• Haemoptysis
• Weight loss
• History of malignancy
• Depending on the
underlying condition
General Examination
• Features of underlying
condition
• Tachypnoic/Anaemia/Lymph
nodes/peripheral oedema
Respiratory System Examination
• Trachea – deviated to
opposite site
• Reduced chest wall
movement and expansion
• Stony dullness on percusion
• Reduced vocal resonance
• Absent breath sounds
Clinical Features of Pleural Effusion

11. • CXR
• Pleural fluid aspiration (pleural tap) +/- Pleural biopsy
• FBC
• ESR/CRP
• Sputum – Full report/Gram stain/AFB stain/Pyogenic and TB culture/
• RFT
• LFT
• TSH
• UFR and urine albumin
• 2D Echo
• USS
• CECT chest
• Bronchoscopy and biopsy/VAT (Video Assisted thoracoscopy)
• Other investigations depending on the cause
Investigations

12. CXR of Pleural Effusion
L L

13. CXR of Pleural Effusion
L L

14. Erect and Lateral Decubitus CXR

15. Pleural Fluid Aspiration (Thoracentesis or Pleural Tap)
• Could be diagnostic or therapeutic
• Diagnostic
– to differentiate transudate or exudate
• Therapeutic
– Massive or rapid fluid collection
– Severe respiratory distress
– Empyema
– Large and mediastinal shift

17. Abram’s Pleural Biopsy Needle

18. Other investigations
• Adenosine Deaminase (ADA)
• pH
• Amylase
• Cholesterol
• Fungal studies
Investigations of Pleural Fluid
• Cytology (including for
malignant cells)
• Protein level
• Glucose
• LDH
• For AFB/TB PCR/TB culture
• Gram stain
• Pyogenic culture

19. How to differentiate transudate or exudate?

20. What are the causes for blood stained pleural
effusion (Haemothorax)?
1. TB
2. Malignancy – Primary or Secondary
3. Chest wall injuries/trauma
4. Pulmonary embolism
5. Pulmonary infarction

21. Treatment
• Depending on the underlying condition
• Therapeutic thoracentesis
• Inter-costal tube (IC tube) insertion and drainage – If
massive pleural effusion
• Pleurodesis