Thrombolytics for acute ischemic stroke
Background
- NINDS Trial (pts treated within 3hrs)
- Benefits:
- 12% absolute risk reduction benefit (NNT = 8-9) at 3 months
- Lower percentage of pts who left hospital severely disabled
- Comparable 3-month mortality rate (even with increased rate of ICH)
- 12% absolute risk reduction benefit (NNT = 8-9) at 3 months
- Risks:
- 1% increase in mortality
- 5% increase in nonfatal intracranial hemorrhage
- Benefits:
- ECASS Trial (pts treated within 4.5hrs)
- Confirmed NINDS findings even when therapeutic window extended to 4.5hr
- As a result AHA/ASA now recommends tPA for pts presenting up to 4.5hr after sx onset
Studies Required
- Physical exam: NIH Stroke Scale
- Head CT
- CBC (Hb, plt)
- PT/PTT/INR
- Only need to wait for result if suspicion of abnormal value, pt has received heparin or warfarin, or use of anticoagulants is unknown
- Glucose
- ECG
- Urine pregnancy (pregnancy is relative contraindication)
tPA <3hr
Inclusion Criteria
- Diagnosis of ischemic stroke causing measurable neuro deficit
- Clear onset (last witnessed well) <3hr (see below for extension to <4.5hr)
- Age >18yr
Exclusion Criteria
- Historical
- Stroke or head trauma in previous 3 months
- Any history of intracranial hemorrhage
- Major surgery in the previous 14 days
- GI or urinary tract bleeding in previous 21 days
- MI in previous 3 months
- Arterial puncture at noncompressible site in previous 7 days
- Clinical
- Spontaneously clearing stroke symptoms
- Only minor and isolated neurologic signs
- Seizure at stroke onset
- Persistent SBP >185 or DBP >110 despite treatment
- Active bleeding or acute trauma (fracture) on exam
- Labs
- Platelets <100K
- Serum glucose <50
- INR >1.7 if on warfarin
- Elevated PTT if on heparin
- Head CT
- Evidence of hemorrhage
- Evidence of multilobar infarction w/ hypodensity involving >33% of cerebral hemisphere
- Use of dabigatran within 48hrs is relative contraindication
tPA between 3-4.5hrs
Inclusion Criteria
- Same as for <3hr
Exclusion Criteria
- All of the above plus:
- Age >80yr
- Combination of both previous stroke and DM
- NIHSS score >25
- Oral anticoagulant use regardless of INR
Administration
- Alteplase 0.9mg/kg IV (max 90mg total)
- 10% of dose is administered as bolus; rest is given over 60min
- Neuo check Q15min x 2hr
- No anticoatulation/antiplatelets x 24hr
- Blood pressure
- Keep SBP <180, DBP <105
- If SBP is 180-230 or DBP is 105-120:
- 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 SBP is >230 or DBP 121-140:
- Labetalol as above OR nicardipine 5mg/hr; titrate up by 2.5 mg/hr at 5-15min intervals; max dose 15mg/hr
- If BP not controlled by above measures:
- Nitroprusside 0.5–10mcg/kg/min
- Continuous arterial monitoring advised
- Use w/ caution in pts with hepatic or renal insufficiency
- Nitroprusside 0.5–10mcg/kg/min
tPA Complications
See Also
Source
- Tintinalli
- Hacke W, Kaste M, Bluhmi E, et al: Thrombolysis with alteplase 3 to 4.5 h after acute ischemic stroke. N Engl J Med 359(13): 1317, 2008
- ACEP/AAN Guidelines
- AHA/ASA Guidelines