What is the recommended management for a loculated pleural effusion?

Treatment of Loculated Pleural Effusion

For loculated pleural effusions, insert a small-bore chest tube (10-14F) under ultrasound guidance and administer intrapleural fibrinolytic therapy if simple drainage fails after 48 hours, as this approach achieves complete resolution in 85-90% of cases while reducing hospital stay and avoiding surgery. 1

Initial Assessment and Imaging

Use transthoracic ultrasonography as your first-line imaging modality to identify septations, which it detects with 81-88% sensitivity and 83-96% specificity—markedly superior to CT scanning (71% sensitivity, 72% specificity). 1 Reserve CT for mediastinal loculations or fissure involvement where ultrasound is limited by overlying lung. 1

All pleural interventions in loculated effusions should be performed under ultrasound guidance, as this reduces complications and increases diagnostic yield. 1

Drainage Strategy

Tube Selection and Placement

Begin with small-bore catheters (10-14F) as your initial choice, as they provide comparable pleurodesis success rates to large-bore tubes (approaching 80%) but with significantly less patient discomfort and easier placement. 2 These can be inserted at bedside by a physician or under radiological guidance. 2

Connect the catheter to underwater seal drainage initially without suction. 3 If the collection persists after 48 hours, apply high-volume, low-pressure suction gradually increasing to -10 to -20 cm H₂O. 2, 3

Controlled Drainage Protocol

Drain large effusions in a controlled fashion to prevent re-expansion pulmonary edema: 2

• Avoid evacuating more than 1-1.5 liters at one time 2
• Slow drainage to approximately 500 ml/hour 2
• Stop aspiration if the patient develops chest discomfort, persistent cough, or vasovagal symptoms 2

Fibrinolytic Therapy

Indications and Timing

Administer intrapleural fibrinolytics if simple drainage fails after 48 hours, particularly when thick fluid or fibrinous debris prevents adequate evacuation. 1, 3 This is especially critical for complicated parapneumonic effusions with loculations. 1

Agent Selection and Dosing

Choose from these fibrinolytic options (no agent has proven superior in head-to-head comparisons): 1

• Urokinase: 100,000 IU once daily 4, 5
• Streptokinase: 250,000 IU twice daily 4
• Alteplase (tPA): 10 mg (or 0.1 mg/kg in pediatrics) 1

Instill the agent with a dwell time of 1-4 hours before reopening the chest tube. 1 Continue for 3 days, then reassess at 5-8 days. 4

Expected Outcomes

Fibrinolytic therapy delivers robust results: 1, 4

• Increased drainage in 93-100% of patients 1, 4
• Complete resolution in 85-86% of cases 1
• Shorter hospital stays: 6.2 days versus 8.7 days with drainage alone 1, 4
• Radiographic improvement: 85% show >40% reduction in pleural opacity versus 35% with placebo 1, 4
• Avoidance of surgery in approximately 90% of cases 1

Safety Profile

Fibrinolytics demonstrate a favorable safety profile with bleeding complications in only 2-8.5% of patients. 1, 4 Alteplase is significantly safer than streptokinase, which causes fever and systemic antibody responses due to its bacterial origin. 1

Critical warning: Patients receiving streptokinase must be given an exposure card and should receive urokinase or tPA for any future systemic indications due to antibody formation. 4

Treatment Algorithm Based on Etiology

Parapneumonic/Infected Loculated Effusions

1. Insert chest tube early when loculation is identified, as loculations are associated with longer hospital stays and more complicated courses. 1
2. Administer appropriate antibiotics alongside drainage (e.g., cefuroxime plus metronidazole, or benzylpenicillin plus ciprofloxacin). 1, 3
3. Add fibrinolytics if drainage inadequate after 48 hours. 1, 3
4. Involve a respiratory physician or thoracic surgeon within 48 hours if the effusion fails to respond, as early specialist involvement reduces delays and morbidity. 1, 3

Malignant Loculated Effusions

Use an indwelling pleural catheter (IPC) as first-line therapy for symptomatic malignant effusions with loculation, as it allows ongoing drainage without requiring complete lung expansion. 1 IPCs are preferred over chemical pleurodesis because pleurodesis will fail if loculations prevent lung re-expansion. 1

Fibrinolytics can be administered through IPCs to improve drainage (successful in 93% of cases), though they do not improve clinical outcomes like dyspnea or pleurodesis success rates in malignant effusions. 1

Pleurodesis Considerations

The most important requirement for successful pleurodesis is satisfactory apposition of parietal and visceral pleura, confirmed radiologically. 2 Incomplete lung re-expansion may result from trapped lung, pleural loculations, proximal airway obstruction, or persistent air leak. 2

Even when only partial pleural apposition is achieved, attempt chemical pleurodesis, as it may still provide symptomatic relief—one study reported favorable response in 9 of 10 patients with partial re-expansion. 2

Once lung re-expansion is radiographically confirmed, proceed with pleurodesis immediately—do not delay waiting for pleural fluid drainage to fall below 150 ml/day, as this only prolongs hospital stay without improving success rates (which approach 80% in both scenarios). 2

Administer lignocaine 3 mg/kg (maximum 250 mg) intrapleurally just prior to sclerosant administration. 2

Surgical Intervention

Consider Video-Assisted Thoracoscopic Surgery (VATS) if medical management fails after approximately 7 days. 1, 3 VATS allows septations to be broken up under direct vision and has demonstrated similar outcomes to chest tube drainage with fibrinolytics in randomized trials. 1

Critical Pitfalls to Avoid

• Never attempt pleurodesis in patients with non-expandable lung due to loculations, as it will fail and not result in definitive fluid control. 1
• Do not rely solely on CT for detecting septations when ultrasound is available, as ultrasound is superior. 1
• Do not delay drainage of large loculated effusions or those causing respiratory distress. 1
• Do not fail to use adjunctive therapy (fibrinolytics or VATS) when simple drainage is inadequate. 1
• Never clamp a bubbling chest tube, as this can convert a simple pneumothorax into life-threatening tension pneumothorax. 3

Monitoring Response

Evaluate treatment effectiveness at 5-8 days after initiating fibrinolytic therapy. 4 Key indicators of successful treatment include: 4

• Resolution of fever and sepsis
• Increased daily drainage output
• Radiographic improvement with reduction in pleural opacity