What is pleurodesis?

Pleurodesis: Definition and Clinical Applications

Pleurodesis is a medical procedure that creates adhesions between the visceral and parietal pleural surfaces to obliterate the pleural space, preventing accumulation of air or fluid. 1, 2

Mechanism of Action

Pleurodesis works through several biological mechanisms:

• Induces inflammation between pleural layers
• Creates a coagulation-fibrinolysis imbalance favoring fibrin adhesion formation
• Recruits fibroblasts that proliferate and produce collagen
• Results in permanent adhesion between pleural surfaces 3

Types of Pleurodesis

1. Chemical Pleurodesis

• Involves instillation of sclerosing agents into the pleural space via chest tube or thoracoscopy
• Common sclerosing agents include:
  • Talc (most effective with 93% success rate)
  • Doxycycline
  • Bleomycin
  • Povidone-iodine 1, 2

2. Mechanical Pleurodesis

• Performed during thoracotomy or thoracoscopy
• Involves mechanical irritation of pleural surfaces or partial pleurectomy
• Techniques include:
  • Pleural abrasion
  • Parietal pleurectomy
  • Talc poudrage (direct application of talc during surgery) 1, 2

Primary Indications

1. Malignant Pleural Effusions

   • First-line treatment for recurrent malignant effusions
   • Prevents fluid re-accumulation and associated symptoms
   • Improves quality of life in patients with advanced malignancy 1, 4

2. Recurrent Pneumothorax

   • Used when pneumothorax is difficult to manage or recurrent
   • Chemical pleurodesis should only be attempted if patient is unwilling or unable to undergo surgery
   • Surgical approaches have lower recurrence rates than medical pleurodesis 1, 5

Procedural Techniques

Chemical Pleurodesis via Chest Tube

1. Complete drainage of pleural fluid/air
2. Confirmation of complete lung re-expansion (essential for success)
3. Instillation of sclerosing agent (for talc: 4-5g mixed with 50ml normal saline)
4. Chest tube clamping for 1 hour
5. Application of 20cm H₂O suction after unclamping
6. Removal of chest tube when 24-hour drainage is 100-150ml 1, 6

Thoracoscopic Talc Poudrage

1. Thoracoscopic examination of pleural cavity
2. Complete evacuation of pleural fluid
3. Direct application of approximately 5g talc over pleural surfaces
4. Placement of chest tube
5. Similar post-procedure management as chemical pleurodesis 1

Factors Affecting Success

• Complete lung re-expansion is essential
• Pleural pH <7.2 associated with lower success rates
• Tube size: Large-bore tubes (≥24F) may have higher success rates than small-bore tubes (12F)
• Distribution of sclerosing agent throughout pleural space 6
• Tumor burden: High tumor burden with few normal mesothelial cells decreases response 3

Complications

• Pain (most common)
• Fever
• Respiratory failure (rare)
• Acute respiratory distress syndrome (rare with large-particle talc)
• Empyema
• Systemic inflammation 1, 3

Clinical Pearls and Pitfalls

• Pearl: Talc is the most effective agent with highest success rates (93%) 1
• Pearl: Thoracoscopic pleurodesis has higher success rates than bedside instillation 4
• Pitfall: Attempting pleurodesis in patients with trapped lung will likely fail
• Pitfall: Failure to ensure complete drainage and lung re-expansion before instillation
• Pitfall: Using small-particle talc may increase risk of systemic complications 3

Treatment of Pleurodesis Failure

• Consider repeat pleurodesis with same agent
• For malignant effusions: consider thoracoscopy and talc poudrage if initial chemical pleurodesis failed
• For persistent pneumothorax: early surgical referral (3-5 days) is recommended
• Alternative options include pleuroperitoneal shunting or long-term indwelling pleural catheter 1