What is the treatment for a loculated pleural effusion?

Treatment of Loculated Pleural Effusions

For loculated pleural effusions, the recommended treatment approach includes drainage procedures with adjunctive fibrinolytic therapy, especially for moderate to large effusions that are causing respiratory distress or are purulent. 1

Assessment and Imaging

• Transthoracic ultrasonography (TUS) is the preferred imaging modality for identifying septations in loculated effusions with 81-88% sensitivity and 83-96% specificity 1
• CT scanning is more valuable for mediastinal loculations or those involving fissures where ultrasound is limited by overlying lung 1
• Ultrasound guidance reduces complications and increases yield when performing interventions on loculated collections 1

Treatment Algorithm Based on Effusion Size

Small Effusions

• Small uncomplicated parapneumonic effusions (<10 mm rim of fluid or less than one-fourth of hemithorax opacified) generally do not require drainage and can be treated with antibiotics alone 1
• All patients with small effusions in one study recovered without drainage intervention 1

Moderate Effusions

• Moderate effusions associated with respiratory distress should be drained 1
• Only about 27% of moderate effusions without mediastinal shift required drainage in clinical studies 1
• Consider antibiotic therapy alone initially for moderate effusions without respiratory compromise 1

Large Effusions

• Large effusions (>50% of hemithorax opacified) require drainage in approximately 66% of cases 1
• Effusions occupying >40% of the hemithorax are likely to fail simple aspiration and drainage 1

Drainage Options for Loculated Effusions

Chest Tube Drainage with Fibrinolytic Agents

• Drainage by chest thoracostomy tube alone is often ineffective for loculated effusions and requires adjunctive therapy 1
• Intrapleural fibrinolytic agents have been shown to improve fluid drainage in loculated effusions 1
• Fibrinolytic options include:
  • Urokinase (100,000 IU daily for 3 days) 1, 2
  • Streptokinase (250,000 IU twice daily for three doses) 1
  • Tissue plasminogen activator 1

Video-Assisted Thoracoscopic Surgery (VATS)

• VATS allows septations to be broken up under direct vision 1
• Both VATS and chest tube drainage with fibrinolytics have demonstrated similar outcomes in randomized trials 1
• VATS should be performed when there is persistence of moderate to large effusions with ongoing respiratory compromise despite 2-3 days of chest tube management 1

Multiple Loculations

• Thoracic surgery is usually required to access multiple loculations, especially those positioned on the mediastinum 1
• Multiple drains have been used for loculated effusions in pleural infection but are not ideal for malignant pleural effusions 1

Evidence for Fibrinolytic Therapy

• Controlled studies show fibrinolytic therapy results in:

  • Greater radiological lung expansion (96% vs 75% in one study) 1
  • Higher daily drainage volumes 1
  • Shorter hospital stays (6.2 vs 8.7 days in one study) 1
  • Greater reduction in pleural opacity on chest radiography 1

• Small-caliber catheters (8.2 Fr) with urokinase instillation have shown success rates of 94.2% in loculated effusions 2

Special Considerations

• If the underlying lung is non-expandable, pleurodesis will be ineffective and will not result in definitive fluid control 1
• Loculated parapneumonic effusions are associated with longer hospital stays and more complicated courses than simple effusions 1
• Diagnostic analysis of pleural fluid should include:
  • Gram stain and bacterial culture (strong recommendation) 1
  • Antigen testing or PCR to increase pathogen detection 1
  • WBC count with differential to help differentiate bacterial from other etiologies 1

Pitfalls to Avoid

• Relying solely on CT for detection of septations when ultrasound is available (TUS is superior) 1
• Attempting pleurodesis in patients with non-expandable lung 1
• Delaying drainage of large loculated effusions or those causing respiratory distress 1
• Failing to use adjunctive therapy (fibrinolytics or VATS) when simple drainage is inadequate 1