Thrombolytics

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

Indications and Contraindications

• Indications
  • Chest pain > 30 min but less than 12 hrs, not relieved by NTG
  • PCI greater than 90 min away
  • ECG criteria of STEMI
    • STE in 2 contiguous leads
    • Posterior STEMI
    • LBBB with Sgarbossa criteria
• Absolute contraindications
  • Prior ICH
  • Known cerebral vascular lesion, AVM
  • Known intracranial malignancy, primary or mets
  • Ischemic stroke within 3 months, but not ischemic stroke within 3 hrs
  • Suspected aortic dissection
  • Active bleeding or bleeding diathesis, excluding menses
  • Significant closed head/facial trauma within 3 months
• Relative contraindications
  • History of chronic, severe HTN
  • SBP > 180 or DBP > 110 mmHg
  • History of prior ischemic stroke > 3 months, dementia, or other known intracranial pathology not in absolute contraindications
  • Traumatic CPR or CPR > 10 min
  • Major surgery within 3 wks
  • Internal bleeding within 2-4 wks
  • Noncompressible vascular punctures
  • Prior allergic reactions to fibrinolytics
  • Pregnancy
  • Active PUD
  • Use of anticoagulants

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

See Also

• Ischemic stroke
• STEMI