Tissue plasminogen activator (tPA) breaks down blood clots and is used to treat ischemic stroke. It works by converting plasminogen to plasmin, the main enzyme responsible for clot breakdown. tPA can be used to treat stroke, pulmonary embolism, and myocardial infarction. For stroke treatment, tPA must be administered intravenously within 3 hours of symptom onset for eligible patients, who must be screened for risks of intracranial bleeding. Precautions are taken to monitor the patient's neurological status and control blood pressure during and after tPA infusion to minimize bleeding risks.

1. RTPA IN STROKE
TREATMENT

2. • Tissue plasminogen activator is a protien
involved in the breakdown of blood clots. It is
a serine protease found on endothelial cells,
the cells that line the blood vessels

3. ACTION
• As an enzyme, it catalyzes the conversion of
plasminogen to plasmin, the major enzyme
responsible for clot breakdown. Because it
works on the clotting system, tPA is used in
clinical medicine to treat embolic or
thrombotic stroke.

4. CLINICAL APPLICATIONS
tPA is used in diseases that feature blood clots,
such as
• pulmonary embolism,
• myocardial infarction
• stroke

5. Eligibility for IV treatment with rt-PA
Age 18 or older.
Clinical diagnosis of ischemic stroke causing
a measurable neurological deficit.
 Time of symptom onset well established to
be less than 180 minutes before treatment
would begin

6. PATIENT SELECTION:
CONTRAINDICATIONS AND
WARNINGS
– Evidence of intracranial hemorrhage on
pretreatment CT.
– Only minor or rapidly improving stroke symptoms.
– Clinical presentation suggestive of subarachnoid
hemorrhage, even with normal CT.

7. – Active internal bleeding.
– Known bleeding diathesis, including but not
limited to:
• Platelet count < 100,000/mm
• Patient has received heparin within 48 hours and has
an elevated aPTT (greater than upper limit of normal
for laboratory)
• Current use of oral anticoagulants (e.g., warfarin
sodium) or recent use with an elevated prothrombin
time > 15 seconds
– Patient has had major surgery or serious trauma
excluding head trauma in the previous 14 days.

8. – Within 3 months any intracranial surgery, serious
head trauma, or previous stroke.
– History of gastrointestinal or urinary tract
hemorrhage within 21 days.
– Recent arterial puncture at a noncompressible
site.
– Recent lumbar puncture.

9. – On repeated measurements, systolic blood
pressure greater than 185 mm Hg or diastolic
blood pressure greater than 110 mm Hg at the
time treatment is to begin, and patient requires
aggressive treatment to reduce blood pressure to
within these limits.
– History of intracranial hemorrhage.
– Abnormal blood glucose ( < 50 or > 400 mg/dL).
– Post myocardial infarction pericarditis.

10. – Patient was observed to have seizure at the same
time the onset of stroke symptoms were
observed.
• Known arteriovenous malformation, or
aneurysm

11. Treatment
– 0.9 mg/kg (maximum of 90 mg) infused
over 60 minutes with 10% of the total dose
administered as an initial intravenous
bolus over 1 minute.

12. Sequence of Events
– Determine whether time is available to start
treatment with rt-PA before 3 hours.
– Draw blood for tests while preparations are
made to perform non-contrast CT scan.
– Start recording blood pressure.
– Neurological examination.
– CT scan without contrast.

13. – Determine if CT has evidence of hemorrhage.
– If patient has severe head or neck pain, or is
somnolent or stuporous, be sure there is no evidence
of subarachnoid hemorrhage.
– If there is a significant abnormal lucency suggestive
of infarction, reconsider the patient's history, since
the stroke may have occurred earlier.
– Review required test results.
– Hematocrit.Platelets.Blood glucose.PT or aPTT
– Review patient selection criteria.
– Infuse rt-PA.

14. – Give 0.9 mg/kg, 10% as a bolus, intravenously.
– Do not use the cardiac dose.
– Do not exceed the 90 mg maximum dose.
– Do not give aspirin, heparin or warfarin for 24
hours.
– Monitor the patient carefully, especially the
blood pressure. Follow the blood pressure
algorithm
• Monitor neurological status

15. Adjunctive Therapy
• No concomitant heparin, warfarin, or
aspirin during the first 24 hours after
symptom onset.

16. Blood Pressure Control
– Pretreatment.
– Monitor blood pressure every 15 minutes. It
should be below 185/110 mm Hg.

17. Management of Intracranial
Hemorrhage
– Suspect the occurrence of intracranial
hemorrhage following the start of rt-PA infusion
if there is any acute neurological deterioration,
new headache, acute hypertension, or nausea
and vomiting.

18. – If hemorrhage is suspected then do the
following:
• Discontinue rt-PA infusion unless other causes of
neurological deterioration are apparent.
• Immediate CT scan or other diagnostic imaging
method sensitive for the presence of hemorrhage.
• Draw blood for PT, aPTT, platelet count,
fibrinogen, and type and cross (may wait to do
actual type and cross).
• Prepare for administration of 6 to 8 units of
cryoprecipitate containing factor VIII.
• Prepare for administration of 6 to 8 units of
platelets.

19. IF INTRACRANIAL HEMORRHAGE
PRESENT:
• Obtain fibrinogen results.
• Consider administering cryoprecipitate or platelets if
needed.
• Consider alerting and consulting a hematologist or
neurosurgeon.
• Consider decision regarding further medical and/or
surgical therapy.
• Consider second CT to assess progression of
intracranial hemorrhage.
• A plan for access to emergent neurosurgical
consultation is highly recommended.