How long should intrapleural lytics, such as streptokinase (streptokinase) or urokinase (urokinase), be left in place for the management of complicated parapneumonic effusions or empyema?

Duration of Intrapleural Fibrinolytic Therapy

Intrapleural fibrinolytics should be administered for 3 days, with streptokinase given at 250,000 IU twice daily or urokinase at 100,000 IU once daily. 1

Standard Treatment Protocol

The British Thoracic Society guidelines establish the definitive duration and dosing regimen for intrapleural fibrinolytic therapy in complicated parapneumonic effusions and empyema:

• Streptokinase: 250,000 IU twice daily for 3 days 1
• Urokinase: 100,000 IU once daily for 3 days 1

Administration Technique

The fibrinolytic agent should be instilled through the chest tube and left to dwell for 3 hours before unclamping. 2, 3, 4

• Dilute the agent in 100 mL normal saline 2, 3, 5
• Clamp the chest tube for 3 hours after instillation to allow adequate contact time 2, 3
• Resume drainage after the dwell period 2, 4

Clinical Response Assessment

Evaluate treatment effectiveness at 5-8 days after initiating chest tube drainage and antibiotics. 1

Key indicators of successful therapy include:

• Increased drainage volume within the first 24 hours post-instillation (typically 380-420 mL) 2
• Resolution of fever and sepsis 1
• Radiological improvement on chest X-ray or CT scan 2, 5

When to Extend or Modify Treatment

Research studies demonstrate that some patients may require additional doses beyond the standard 3-day protocol:

• The number of instillations may range from 2-10 doses depending on clinical response 2, 3, 6
• Continue therapy if drainage remains productive and clinical improvement is ongoing 3, 5, 4
• Most patients respond adequately with 3-7 total doses (mean 3.7-6.8 doses) 3, 5, 4

If inadequate drainage persists after the initial 3-day course, obtain contrast-enhanced CT scanning to assess for undrained loculations and proper tube positioning. 1

Surgical Consultation Threshold

Discuss with a thoracic surgeon if effective pleural drainage has not been achieved by the 5-8 day assessment point. 1

Failure rates requiring surgical intervention range from 13-28% despite fibrinolytic therapy 2, 3, 5, 4

Important Safety Considerations

Patients receiving intrapleural streptokinase must be given a streptokinase exposure card and should receive urokinase or tissue plasminogen activator for any future systemic indications. 1

Common adverse effects include:

• Fever (particularly with streptokinase) 1, 2, 3
• Transient chest pain during instillation 3, 6
• Rare bleeding complications (pleural hemorrhage, epistaxis) 1

Urokinase is non-antigenic and may be preferred over streptokinase due to lower immunological side effects, though it carries higher cost. 7, 2

Clinical Pitfalls to Avoid

• Do not continue fibrinolytic therapy indefinitely without reassessment—the standard 3-day course should prompt clinical evaluation 1
• Ensure the chest tube is patent before attributing poor drainage to loculations; flush with 20-50 mL normal saline if blockage is suspected 1
• Do not delay surgical consultation beyond 5-8 days if drainage remains inadequate despite fibrinolytic therapy 1