Stroke Flashcards
What is a stroke?
a cerebrovascular accident that occurs when blood flow to an area of the brain is interrupted; can be ischemic or hemorhagic
What is an acute ischemic stroke caused by?
- non-cardioembolic: a thrombus (localized clot) that forms during a cerebral atherosclerotic infarction (obstruction of blood supply)
- cardioembolic: an embolus that forms in the heart and travels to the brain ( commonly caused by A.fib)
What is a hemorrhagic stroke caused by?
- intracranial hemorrhage
- subarachnoid hemorrhage
What is a transient ischemic attack>
cause by a temporary clot ( and blockage of blood flow to the brain) symptoms resemble acute ischemic stroke but resolve within minutes to hours without permanent damage; should be medically managed with the same risk reduction strategies
What are modifiable stroke risk factors?
- HYPERTENSION
- Atrial fibrillation
- dyslipidemia
- diabetes
- physical inactivity
- smoking
What are non-modifiable stroke risk factors?
- Prior stoke or TIA
- advanced age (>80y/o)
- race (higher risk in AA)
- genetic disorders (sickle cell disease)
What are signs and symptoms of stroke?
FAST:
Face drooping (one-sided)
Arm weakness (one sided)
Speech difficulty (slurred)
Time to call 911 (time is brain)
What is used to diagnose stroke?
brain imaging using computed tomography (CT) is ideally performed within 20 minutes of arrival to the ER to quickly identify if the stroke is hemorrhagic or ischemic
What is the immediate goal of treating acute ischemic stroke?
restore blood flow to the ischemic area
What is monitored during the management of acute ischemic stroke?
- intracranial pressure (ICP)
- cerebral perfusion pressure (CPP)
- blood pressure
What agents are fibrinolytic used to treat acute ischemic stoke?
- Alteplase (FDA approved)
- Tenecteplase (off-label)
How does alteplase work to treat acute ischemic stroke?
recombinant tissue plasminogen activator binds to fibrin in a thrombus (clot) and converts plasminogen to plasmin, resulting in fibrinolysis
What patients are candidates for alteplase?
- no bleeding seen on brain imaging
- stroke symptom onset ≤4.5 hours (FDA-approved timeline is ≤ 3 hours)
- alteplase can be administered within 60 minutes of hospital arrival (door-to-needle time)
- no contraindications
What puts patients at increased risk for bleeding when using alteplase?
- active internal bleed (intracranial hemorhage)
- severe hypertension (>185/110 mmHg)
- other conditions/head trauma
- Labs (elevated INR, low platelets)
- drug interactions (anticoagulant use)
What are CIs with alteplase?
- active internal bleeding or known bleeding diathesis
- history of recent stroke (past 3 months)
- severe uncontrolled HTN (>185/110)
- any prior ICH
- treatment dose of LMWH (w/in 24 hours)
- use of direct thrombin inhibitor or Xa inhibitor (w/in 48 hours)
- taking warfarin with INR >1.7
- blood glucose <50
- labs (INR >1.7, Plt <100,000, aPTT>40)
- other conditions that increase risk of bleeding
What are SEs with alteplase?
major bleeding (ICH)
What should be monitored when taking alteplase?
- Hgb/Hct
- s/sx bleeding
- neurological assessment
- BP ( must be <180/105 before alteplase is administered and maintained for at least 24 hours during the infusion, usually IV nicardipine or labetalol used)
- head CT 24 hours after treatment, before starting antiplatelets/anticoagulants
What is dosing of alteplase?
0.9 mg/kg (MAX 90mg dose)
administer 10% of the calculated dose as a plus over 1 min then infuse the remainder over 60 min
Alteplase
Activase
Cathflo Activase
What should be done if severe headache, acute HTN, N/V, or worsening of neurological function occurs during alteplase injection?
D/C infusion and obtain emergent head CT
Which dosage form of alteplase is used to clear clotted central IV lines and devices?
Cathflo Activase (2mg vial)
What drugs interact with alteplase?
additive effects with other drugs that increase bleeding
What other treatments are used for acute ischemic stroke?
- aspirin
- DVT prophylaxis
- HTN management
- Hyperglycemia management
When should aspirin be started for acute ischemic stroke?
- initiate aspirin 81-325mg PO QD within 48 hours after stroke onset
- do not administer within 24 hours of fibrinolytic use
How should HTN be managed if alteplase is NOT used?
- IV antihypertensives may not be needed unless BP ≥220/120; 15% reduction reduction in BP in the first 24 hours after stroke onset is safe
- once neurologically stable PO antihypertensive can be used
How is hyperglycemia managed with acute ischemic stroke?
maintain glucose 140-180 to prevent hypoglycemia
What MUST be done before initiating alteplase?
rule out hemorrhagic stroke (ICH, SAH)
What agents are recommended for HTN treatment in patients with previous stroke TIA?
- thiazide diuretics
- ACE/ARB
What agents are recommended for dyslipidemia treatment in patients with previous stroke TIA?
high-intensity statin (guidelines recommend atorvastatin 80mg/day); if not able to achieve LDL goal, add ezetimibe or PCSK9 monoclonal antibody
What lifestyle modifications should be made as secondary prevention of stroke/TIA?
- smoking cessation
- heart-healthy diet (Mediterranean)
- sodium restriction (<1.5g/day)
- physical activity (10 min 4x/wk or 20 min 2x/wk)
- maintain BMI 18.5-24.9
- maintain waist circumference <35 inches (women) and <40 (men)
- limit alcohol intake ≤1 drink/day (women) and ≤2 drinks/day (men)
What is recommended for patients who had non-cardioembolic stroke to reduce risk of recurrence?
aspirin, aspirin + ER dipyridamole, or clopidogrel
What drug is CI in patients with a history of TIA or stroke due to increased intracranial bleeding risk?
Prasugrel
What can be initiated for minor ischemic stroke if alteplase was not used?
aspirin + clopidogrel initiated within 24 hours and continued for 21-90 days