Streptokinase for Flushing Blocked IV Lines
No, streptokinase should not be used to flush blocked IV lines—recombinant tissue plasminogen activator (rtPA) or urokinase are the recommended thrombolytic agents for catheter occlusion.
Recommended Thrombolytic Agents for Catheter Occlusion
The ESPGHAN/ESPEN/ESPR/CSPEN guidelines explicitly state that recombinant tissue plasminogen activator or urokinase shall be used to unblock a catheter (strong recommendation, high-quality evidence) 1. This represents the current standard of care based on the highest quality evidence available.
Why Streptokinase Is Not Appropriate
Lack of Guideline Support
- No major clinical guidelines recommend streptokinase for IV line clearance 1
- The American Heart Association guidelines specifically state that intravenous administration of streptokinase for treatment of stroke is not recommended (Class III recommendation), and similarly advise against using streptokinase, urokinase, or other thrombolytic agents outside clinical trial settings for most indications 1
Significant Immunogenicity Issues
- Streptokinase is highly antigenic and triggers robust immune responses, leading to persistent neutralizing antibodies 2
- These antibodies can cause serious allergic reactions and render the drug ineffective 2
- Streptokinase should never be re-administered within 6 months of initial use due to antibody formation—this is an absolute contraindication 2
Systemic Effects and Safety Concerns
- Even low-dose streptokinase (5,000 U/hr) causes systemic fibrinolysis in 100% of patients, with 82% showing 50% decrease in plasma fibrinogen within 4 hours 3
- Major hemorrhagic complications occur in approximately 10-16% of patients receiving streptokinase 3, 4
- Bleeding complications do not correlate with dose, making it unpredictable for local catheter use 3, 4
Practical Algorithm for Catheter Occlusion
First-Line Approach
- Use rtPA (alteplase): Instill into the occluded catheter lumen and allow to dwell 1
- Alternative: Urokinase if rtPA is unavailable 1
Key Advantages of rtPA/Urokinase Over Streptokinase
- Non-antigenic: Can be safely re-administered without antibody formation 2
- More fibrin-specific: Less systemic fibrinolysis and lower bleeding risk 2
- Guideline-supported: Strong evidence base for catheter clearance 1
Monitoring During Thrombolytic Catheter Clearance
- Watch for signs of bleeding (particularly important if systemic absorption occurs) 3
- Monitor hemoglobin/hematocrit if prolonged dwell time or multiple doses required 1
Common Pitfall to Avoid
Do not extrapolate streptokinase's use in other thrombotic conditions (MI, DVT, peritoneal catheters) to IV line occlusion 5, 6. While historical literature describes streptokinase for peritoneal catheter failure 6, modern guidelines have moved away from streptokinase due to superior alternatives with better safety profiles 1, 2.