Thrombolytics

Thrombolysis contraindications

Absolute contraindication

• Any prior ICH
• Known structural cerebral vascular lesion (AVM)
• Known intracranial neoplasm
• Ischemic stroke within 3 mo
• Active internal bleeding (excluding menses)
• Suspected aortic dissection or pericarditis

Relative contraindications

• Severe uncontrolled BP (>180/110)
• History of chronic severe poorly controlled hypertension
• History of ischemic stroke within past 3 months
• Known intracranial pathology not covered in absolute contraindications
• Current use of anticoagulants with known INR >2–3
• Known bleeding diathesis
• Recent trauma (past 2 wk)
• Prolonged CPR (>10 min)
• Major surgery (<3 wk)
• Noncompressible vascular punctures (e.g. subclavian) within past 7 days
• Recent internal bleeding (within 2–4 wk)
• Patients treated previously with streptokinase should not receive streptokinase again
• Pregnancy
• Active peptic ulcer disease
• Other medical conditions likely to increase risk of bleeding (diabetic retinopathy, etc)

Thrombolysis in Acute Ischemic Stroke (tPA)

Alteplase

• NOTE - in stroke, do not give aspirin until 24 hours after giving tPA, as ASA with tPA does not improve outcomes and increases bleed risk
• Do not give acutely heparin (or any anticoagulation) if giving tPA

Dosing:

• 0.9mg/kg IV (max 90mg total)
  • 10% of dose is administered as bolus; rest is given over 60min
• Neuro check Q15min x 2hr
• No anticoagulation/antiplatelets x 24hr
• Blood pressure (keep SBP <180, DBP <105)

If SBP is >180-230 or DBP is >120:

• Nicardipine 5 mg/hr by slow infusion (50 mL/hr) initially; may be increased by 2.5 mg/hr every 15 minutes; not to exceed 15 mg/hr OR
• Labetalol 10mg IV over 1–2 min; repeat dose q10–20min up to 300mg max OR
• Labetalol 10mg IV followed by infusion at 2–8 mg/min

If BP not controlled by above measures:

• Nitroprusside 0.5–10mcg/kg/min
• Continuous arterial monitoring advised
• Use with caution in patients with hepatic or renal insufficiency

Thrombolysis in Pulmonary Embolism

• See Thrombolysis for PE

Thrombolytics in STEMI

Alteplase (TPA)

Dosing based on patient weight:

• 67kg: Infuse 15mg IV over 1-2min; then 50mg over 30min; then 35mg over next 60min (i.e. 100mg over 1.5hr)
• ≤67kg: Infuse 15mg IV over 1-2min; then 0.75 mg/kg (max 50mg) over 30 min; then 0.5 mg/kg over 60min (max 35 mg)

Tenecteplase (TNKase)

• Reconstitute 50 mg vial in 10 mL sterile water (5 mg/mL)
• < 60 kg = 30 mg IV push over 5 seconds
• 60-69 kg = 35 mg IV push over 5 seconds
• 70-79 kg = 40 mg IV push over 5 seconds
• 80-89 kg = 45 mg IV push over 5 seconds
• > 90 kg = 50 mg IV push over 5 seconds

See Also

• Ischemic stroke
• STEMI