Hematology: Thrombolytics

Thrombolytics

Definitions

  • Anticoagulation: Prevents Coagulation & Further Clot Propagation
  • Thrombolysis: Directly Breaks Down Clots

Thrombolytics (Fibrinolytics)

  • Drugs: Recombinant Tissue Plasminogen Activator (tPA)
    • Alteplase (Activase)
    • Reteplase (Retavase)
    • Tenecteplase (TNKase)
  • Mechanism: Activates Plasminogen (Degrades Fibrin/Platelet Plug)
    • Can Be Given Systemically or Catheter-Directed
  • Monitor: Fibrinogen Levels (Increased Risk of Bleeding if < 150 mg/dL)
  • Reversal for Bleeding: Cryoprecipitate & FFP
    • May Also Consider TXA or ε-Aminocaproic Acid (Amicar) – Benefits Unclear
  • Possible Indications:
    • Acute Myocardial Infarction
    • Pulmonary Embolism
    • Acute Limb Ischemia Due to Thromboembolism

tPA Contraindications

  • Absolute:
    • Active Internal Bleeding
    • Known Bleeding Diathesis (Platelet Count < 100,000, INR > 1.7, Certain Anticoagulants)
    • Recent GI Bleed in the Past 21 Days
    • Intracranial Hemorrhage (ICH) – Acute or Any History of
    • Uncontrolled Hypertension (SBP > 185 mmHg or DBP > 110 mmHg)
    • In the Past 3 Months:
      • Serious Head Trauma
      • Stroke
      • Neurosurgery
    • Known Intracranial Arteriovenous Malformation, Aneurysm or Neoplasm
    • Endocarditis
  • Relative:
    • Major Surgery or Serious Trauma ≤ 14 Days Ago
    • Recent GU Hemorrhage ≤ 21 Days Ago
    • Pregnancy
    • Recent MI ≤ 3 Months Ago
  • *There is Variation Among Recommendations