Ch33: Stroke

Question 1

Acute ischemic stroke causes

Answer 1

1. Non-cardioembolic: Thrombus/localized clot from atherscletoic infarction in brain
2. Cardioembolic: Embolus from heart that travels to brain, commonly d/t AF

Question 2

Hemorrhage stroke types

Answer 2

• Intracerebral hemorrhage (ICH)
• Subarachnoid hemorrhage (SAH)

Question 3

Modifiable RFs for stroke

Answer 3

• HTN - most important *
• AF *
• Dyslipidemia
• Diabetes
• Physical inactivity
• Smoking

Question 4

Non-modifiable RFs for stroke

Answer 4

• H/o stroke/TIA *
• ≥ 80 y.o.
• Black
• Genetic diseases (SCD)

Question 5

What imaging should be done quickly for suspected stroke? Why and what is the time frame?

Answer 5

• Brain imaging w/ CT *
• Within 20min ED arrival
• To identify if s/sx are d/t hemorrhage *

Question 6

What elements/drugs are involved in the acute management of an ischemic stroke?

Answer 6

• IV fibrinolytics
• Aspirin
• DVT prevention w/ intermittent pneumatic compression devices

Question 7

When should aspirin be initiated in ischemic stroke? Dose? Considerations with fibrinolytic therapy?

Answer 7

• 81-325 PO daily within 48h after stroke onset *
• Do NOT give within 24h fibrinolytic therapy *

Question 8

Alteplase MOA

Answer 8

• Recombinant tissue plasminogen activator (tPA) *
• Binds fibrin and plasminogen in clot to convert to plasmin *

Question 9

Warnings for alteplase

Answer 9

BLEED RISK * :
Active internal bleed

Risk of internal bleed d/t:
- BP > 185/110 (can decrease w/ IV meds)
- Head trauma
- Labs (high INR, low plt)
- DDIs

Question 10

Alteplase CIs

Answer 10

• Active internal bleeding
• H/o recent stroke within 3 mths
• BP > 185/110
• BG < 50
• INR > 1.7
• Treatment dose of LMWH within 24h
• Treatment dose of direct thrombin inhibitor or Xa-inhibitor within 48h
• Others - not underlined

Question 11

Alteplase monitoring

Answer 11

• Hgb
• Hct
• S/sx bleeding
• Neuro assessment
• BP < 185/110 - maintain < 180/105 for at least 24h after infusion

Question 12

Requirements to start alteplase and time requirements

Answer 12

• No bleeding on CT
• Stroke onset ≤ 4.5h

Question 13

Are there different CIs and dosing for alteplase in ACS and PE? Why?

Answer 13

Yes - higher risk of hemorrhagic conversion with strokes

Question 14

Alteplase dosing for ischemic STROKE

Answer 14

0.9 mg/kg, max 90mg

Question 15

Which antihypertensives can be used in stroke pts to reach alteplase requirements?

Answer 15

Labetalol or nicardipine

Question 16

Secondary prevention - HTN agents and goal BP

Answer 16

• Best risk reduction: Thiazide diuretics, ACE/ARBs
• Goal BP < 130/80

Question 17

Secondary prevention - dyslipidemia

Answer 17

High intensity statin

Question 18

Secondary prevention - lifestyle modification

BMI, waist circumference, sodium restriction

Answer 18

• Stop smoking
• Diet (sodium restriction < 1.5 g/d) to decrease BP
• Physical activity
• BMI 18.5-24.9
• Waist circumference < 35 in F, < 40 in M
• Restrict alcohol intake

Question 19

Secondary prevention - What type of stroke needs antiplatelet treatment?

Answer 19

Non-cardioembolic: ischemic stroke or TIA

Question 20

Secondary prevention stroke - Which antiplatelet agents can be used?

Answer 20

• Aspirin
• Aspirin + dipyridamole ER
• Clopidogrel

Question 21

Secondary prevention - what is the purpose of antiplatelet treatment in stroke prevention?

Answer 21

Decreases risk of current stroke

Question 22

Prasugrel contraindication related to strokes

Answer 22

CI in h/o stroke or TIA

Question 23

Antiplatelet therapy - when is dual antiplatelet therapy indicated in stroke? What agents are used?

Answer 23

• Can initiate clopidogrel + low-dose aspirin for minor ischemic stroke
• Do NOT use long-term as secondary prevention d/t increased risk of hemorrhage
• Indefinite MONOtherpay

Question 24

If a patient is already taking daily aspirin and then they have a stroke or TIA, is it beneficial to increase the daily aspirin dose?

Answer 24

NO

Question 25

Aspirin MOA

Answer 25

Irreversibly inhibits COX-1 and 2 -> decreased prostaglandin and thromboxane A2 (TXA2) production | TXA2 = potent vasoconstrictor and inducer of platelet aggregation

Question 26

Dipyridamole (given w/ aspirin) MOA

Answer 26

Inhibits adenosine uptake into platelets -> increased cAMP -> inhibits platelet aggregation

Question 27

Clopidogrel MOA

Answer 27

- PRODRUG - Irreversibly inhibits P2Y12 ADP-mediated platelet activation and aggregation

Question 28

What symptom can occur in salicylate OD?

Answer 28

Tinnitus

Question 29

Why should children/teens with a recent/current viral infection NOT use salicylates?

Answer 29

Risk of Reye's Syndrome

Question 30

ADRs of antiplatelets

Answer 30

- Dyspepsia - Heartburn - Bleeding

Question 31

Specific ADRs of dipyridamole ER

Answer 31

- Hypotension (in CAD pts d/t vasodilatory effects) - HA

Question 32

What drug class can be protective with chronic NSAID therapy? What are its potential downsides?

Answer 32

- PPIs to protect gut - Can decrease BMD, and increase infection risk

Question 33

Aspirin dose range

Answer 33

50-325 mg once daily

Question 34

What ASA dosage formulations are available OTC?

Answer 34

- Tablets - Chewable tabs - EC - Suppository

Question 35

What ASA formulations are available as Rx only?

Answer 35

- ER capsule - DR tablet

Question 36

What CYP enzyme is needed for clopidogrel activation?

Answer 36

CYP2C19 - check genotype

Question 37

What medications related to CYP2C19 should NOT be used with clopidogrel?

Answer 37

Omeprazole, esomeprazole

Question 38

How many days before an elective surgery should clopidogrel be held?

Answer 38

5d