Streptokinase Dosing for Acute Massive Pulmonary Thromboembolism
The recommended dose of streptokinase for thrombolysis in acute massive pulmonary thromboembolism (PTE) is 250,000 IU given as a loading dose over 20-30 minutes, followed by 100,000 IU/hour intravenously for up to 24 hours. 1
Dosing Regimen Details
- Loading dose: 250,000 IU over 20-30 minutes
- Maintenance dose: 100,000 IU/hour intravenous infusion
- Duration: Up to 24 hours, depending on clinical response
Alternative Regimens
Some evidence suggests that a shorter, higher-dose regimen may also be effective:
- 1.5 million IU administered over 2 hours (similar to myocardial infarction dosing) 2, 3
- This shorter regimen has shown comparable efficacy to alteplase in some studies 2
Indications for Thrombolysis
Streptokinase thrombolysis should be used in:
- Patients with massive PTE causing hemodynamic instability, particularly with hypotension 1
- Patients with acute massive embolism with obstruction of blood flow to a lobe or multiple segments 1
Monitoring During Treatment
- Perform Doppler echocardiography every 2-3 hours to monitor hemodynamic effects 1
- Stop infusion when pressure gradient and valve area return to normal or near normal 1
- Monitor for signs of bleeding complications
- Consider hydrocortisone administration to reduce allergic reactions 1
Contraindications
Absolute contraindications:
- Recent hemorrhage
- Stroke
- Current gastrointestinal hemorrhage 1
Relative contraindications:
- Peptic ulcer disease
- Surgery within the preceding seven days
- Prolonged cardiorespiratory resuscitation 1
Important Considerations
Antigenic properties: Streptokinase is highly antigenic and can lead to the development of neutralizing antibodies, limiting its use in subsequent episodes 1
Bleeding risk: High-risk patients include those who have undergone surgery, obstetric delivery, or invasive vascular studies within the preceding seven days, and those with peptic ulcer disease or other bleeding disorders 1
Pregnancy considerations: Thrombolysis may be appropriate for massive PE during pregnancy, but not within six hours of delivery nor in the early post-partum period due to high bleeding risk 1
Treatment failure: If no improvement is seen after 1 hour of thrombolytic therapy, consider pulmonary embolectomy 1
Alternative Thrombolytic Agents
If streptokinase cannot be used due to previous exposure or allergy:
- Urokinase: 4,400 U/kg per hour 1
- Alteplase (rtPA): Has been used with comparable efficacy but at higher cost 1, 2
Follow-up After Thrombolysis
- Transition to heparin anticoagulation after thrombolytic therapy
- Begin heparin as soon as the APTT is less than twice the upper limit of normal 1
- Continue with oral anticoagulation as appropriate for long-term management
Thrombolysis with streptokinase has been shown to improve outcomes in patients with massive PTE, with evidence suggesting reduced mortality compared to heparin alone in hemodynamically unstable patients 4, 3.