Stroke

Front 1

Thrombolytic therapy for acute ischemic stroke involves alteplase (activase, rt-PA). It is important to confirm a clot through head CT before administering. What is the mechanism of alteplase?

Back 1

Recombinant tissue plasminogen activator (rt-PA) causes fibrinolysis by binding to fibrin in a thrombus (clot) and converts entrapped plasminogen to plasmin

Front 2

How is alteplase dosed?

Back 2

0.9 mg/kg (max dose 90 mg) IV over 60 minutes with 10% of the dose given as a bolus over 1 minute

Front 3

Key Contraindications for alteplase?

Back 3

Active bleed
Recent surgery
Plt count < 100,000
INR > 1.7
Previous ICH, stroke, serious head trauma, intracranial neoplasm
BP > 185/110 mmHg

Front 4

What other two therapies are used in acute ischemic stroke?

Back 4

(Anti-platlet) Aspirin 325 PO daily - oral administration is recommended 24-48 hours after stroke onset in most patients - Not recommended within 24 hours of thrombolytic therapy

(Anti-hypertensive therapy) Labetalol and Nicardipine
Used to decrease BP and possibly qualify patient for t-pa

Front 5

Pharmacologic therapy for ICH includes:

Why?

Back 5

Mannitol (Osmitrol)

Increases osmotic pressure to reduce intracranial pressure associated with cerebral edema

Front 6

Pharmacologic therapy for Subarachnoid Hemorrhage includes:

What caution needs to be taken with this?

Back 6

Nimodipine (Nimotop) - Dihydropyridine CCB


Nimodipine is for oral use only, but is sometimes put into syringes from the capsule for NG administration - people have been given this formulation IV and it has caused death - label syringe "for oral use only"

Front 7

Modifiable risk factors for ischemic stroke prevention:



Lifestyle changes:

Back 7

Hypertension
Hypercholesterolemia
Tight glucose control (microvascular disease)

Smoking cessation, increased physical exercise (30 min most days of the week), BMI 18.5-24.9, Waist circumference < 35 in (women), < 40 in (men) and limit alcohol intake (<2 for men, <1 for females)

Front 8

Secondary prevention of acute ischemic stroke involves:

Back 8

Cardioembolic stroke: anticoagulation therapy

Non-cardioembolic stroke: anti-platelet therapy [Aspirin, Clopidogrel (Plavix), Dipyridamole ER/Aspirin (Aggrenox)]

Front 9

Aspirin contraindications:

Back 9

NSAID/Salicylate allergy
Children < 16 years old with viral infection (Reyes syndrome risk)

Front 10

Clopidogrel black box warning:

Back 10

Diminished effectiveness in poor metabolizers
Effectiveness depends on activation via CYP 2C19
CYP 2C19 - 1 allele is fully functional
CYP 2C19 - 2/3 allele are nonfunctional

Front 11

Rare side effect of clopidogrel (in addition bleeding, bruising etc):

Back 11

Thrombotic thrombocytopenic purpura (TTP)

Front 12

CYP 2C19 inhibitors that may decrease clopidogrel effectiveness:

Back 12

Cimetidine, fluconazole, ketoconazole, voriconazole, fluoxetine, fluvoxamine
Omeprazole, esomeprazole