tissue plasminogen activator (tPA), alteplase – Flashcards

Activase

thrombolytic enzyme

50 and 100 mg vials

- An enzyme produced by recombinant DNA technology. Identical to naturally occurring human tPA, an enzyme that promotes conversion of plasminogen to plasmin, an enzyme that digests the fibrin matrix of clots. Low therapeutic doses produce selective activation of plasminogen that is bound to fibrin in thrombi resulting in minimal activation of plasminogen in the general circulation.

- Lysis of thrombi obstructing coronary arteries in management of acute MI. - Lysis of thrombi obstructing cerebral arteries in the management of acute ischemic stroke. - Lysis of thrombi obstructing pulmonary arteries in the management of pulmonary embolism.

Accelerated infusion (1.5 hours): Give 15 mg IV bolus Then give 50 mg infused over 30 min Then 35 mg infused over 60 min

Head trauma or prior stroke in previous 3 months Symptoms suggest subarachnoid hemorrhage Arterial puncture at non-compressible site in previous 7 days History of previous intracranial hemorrhage Elevated blood pressure (systolic > 185 mm Hg or diastolic > 110 mm Hg) Evidence of active bleeding on examination Acute bleeding diathesis, including but not limited to Platelet count upper limit of normal Current use of anticoagulant with > INR 1.7 or PT 15 seconds Blood glucose concentration 1/3 cerebral hemisphere)

Age > 80 years Severe stroke (NIHSS > 25) Taking an oral anticoagulant regardless of INR History of both diabetes and prior ischemic stroke

Recent experience suggests that under some circumstance with careful consideration and weighing of risk to benefit patients may receive fibrinolytic therapy despite 1 or more relative contraindications. Consider risk to benefit of tPA administration carefully if any of these relative contraindications is present Only minor or rapidly improving stroke symptoms (clearing spontaneously) Seizure at onset with postictal residual neurologic impairments Major surgery or serious trauma within previous 14 days Recent gastrointestinal or urinary tract hemorrhage (within previous 21days) Recent acute myocardial infarction (within previous 3 months)

Any prior intracranial hemorrhage Known structural cerebral vascular lesion (e.g., AVM) Known malignant intracranial neoplasm (primary or metastatic) Ischemic stroke within 3 months EXCEPT acute ischemic stroke within 3 hours Suspected aortic dissection Active bleeding or bleeding diathesis (excluding menses) Significant closed head trauma or facial trauma within 3 months

History of chronic, severe, poorly controlled hypertension Severe uncontrolled hypertension on presentation (SBP > 180 mm Hg or DBP >110 mm Hg) - could be a contraindication in low-risk patients with MI History of prior ischemic stroke > 3 months, dementia, or known intracranial pathology not covered in contraindications Traumatic or prolonged (> 10 minutes) CPR or major surgery ( 5 days ago) or prior allergic reaction to these agents Pregnancy Active peptic ulcer Current use of anticoagulants: the higher the INR, the higher the risk of bleeding

Total doses in excess of 100 mg are associated with an increased risk of intracranial bleeding and should be avoided. Due to the urgency of administering thrombolytic therapy within a limited time period, rapid EMS response, assessment, recognition and transport are critical elements in the prehospital management of the MI and stroke patient. Onset of time of stroke is either witnessed or last known normal Must be reconstituted with sterile water to 1 mg/ml Use 2 peripheral IV lines, one exclusively for fibrinolytic administration.