Criteria to be met

• Systolic BP <90 mmHg after standard treatment for 30–60 min
• Pulmonary embolism confirmed on CT pulmonary angiography, or supported by echocardiographic findings (Table 57.3)
• No active bleeding (other contraindications to thrombolysis (Table 45.2) are relative in the context of immediately life-threatening pulmonary embolism)

Thrombolytic therapy can be given via a peripheral or central vein

Streptokinase

• 250,000 U IV over 30 min, followed by
• 100,000 U/h IV for 12–72h

• 10 mg IV over 1–2 min IV, followed by
• 90 mg IV over 2 h (maximum total dose 1.5/kg in patients < 65kg)
• Check the thrombin time (TT) or
  activated partial thromboplastin time (APTT) 3–4h after stopping streptokinase or alteplase. When TT/APTT are less than twice control, restart heparin