Stroke Flashcards
What are some modifiable risk factors (6) and non-modifiable risk factors (4) of stroke?
Modifiable:
- hypertension (most important)
- atrial fibrillation
- dyslipidemia
- diabetes
- physical inactivity
- smoking
Non-modifiable:
- prior stroke or TIA
- advanced age (≥ 80 years old)
- race (higher risk in AA patients)
- genetic diseases (ex. sickle cell)
How do we determine severity of a stroke? What imaging options do we have for stroke?
Use National Institutes of Health Stroke Scale (NIHSS) to help determine the severity of the stroke a guide treatment - max is 42
Brain imaging using CT w/in 20 mins of arrival can help identify where the stroke is hemorrhagic. Could also use MRI, but this is slower, less common, and often note available in the ED
What is the first priority in acute ischemic stroke management and what options (2) do we have for it?
- Restore blood flow
- fibrinolytics (ex. alteplase): these bind fibrin in a clot and convert plasminogen to plasmin
- remove blockage (thrombectomy)
What is the MOA of alteplase? What is the goal door-to-needle time? What is the time frame that symptom onset needs to be to get tPA?
tPA = tissue plasminogen activator
MOA - binds to fibrin in a thrombus, which causes the conversion of plasminogen to plasmin. Plasmin (endogenous protease) works to break down fibrin clots (aka fibrinolysis)
Goal: door-to-needle w/in 60mins of arrival
Important to know “last known well”
- FDA approved: w/in 3 hours of symptom onset
- Off-label but guideline recommended: w/in 4.5 hours of symptom onset
What are the contraindications to alteplase? (ABCD)
Active Bleed - any internal bleeding (head CT to rule out bleed)
Conditions, labs, or vitals that increase bleeding risk - hx of recent stroke or head trauma w/in last 3 months, intracranial hemorrhage, aneurysm, blood pressure > 185/110 mmHg, INR >1.7, apTT > 40 sec, plt < 100k, blood glucose < 50mg/dL
Drug interactions - treatment dose LMWH in past 24 hours, direct thrombin inhibitor or direct factor Xa inhibitor in past 48 hours
What is the recommended dosing/administration of alteplase for acute ischemic stroke management?
0.9mg/kg (max dose 90mg)
10% is given as a bolus over 1 min, then the remainder is given as an infusion over 1 hour
What treatments/considerations do we have besides alteplase for acute ischemic stroke treatment? (4)
aspirin 81-325mg PO within 24-48 hours after a stroke (not w/in 24 hours of a fibrinolytic)
blood pressure management:
- before alteplase, BP must be <185/110mmHg
- during and after alteplase, BP must be <180/105 mmHg for at least 24 hours after
- permissive hypertension (if no tPA given)
blood glucose control: target 140-180 mg/dL
DVT ppx
What are the antiplatelet treatment options for ischemic stroke?
Start within 24-48 hours after a stroke
- aspirin
- clopidogrel
- aspirin/ER dipyridamole
- can do ASA + clopidogrel for 21-90 days in some cases
(FYI no benefit of increasing ASA dose if pt already on ASA before stroke occurred)
What 4 modifiable risk factors do we need to focus on for secondary prevention of an ischemic stroke? What are our goals/treatment options for those?
Hypertension
- goal <130/80
- meds: thiazide, ACE inhibitor, ARB
Dyslipidemia
- follow DLD guidelines
- high-intensity statin (clinical ASCVD)
- PCSK9 inhibitor or ezetimibe if needed
Diabetes
- screening for all patients
- DM + ASCVD = GLP-1 agonist or SGLT2 inhibitor
Lifestyle modifications
- smoking cessation
- nutrition
- physical activity
- weight reduction
- reduce alcohol use
Aspirin (for stroke) - MOA, dosing, contraindications (2), warnings (2), side effects (3), other notes (1)
MOA - irreversibly inhibitor of COX-1 and 2, leading to decreased prostaglandin and thromboxane A2, which ultimately decreases platelet activation
Dose: 50-325mg daily
Contraindications: NSAID or salicylate allergy, children/teenagers with viral infection (Reye’s syndrome)
Warnings - bleeding, tinnitus (overdose)
Side effects - dyspepsia, heartburn, bleeding
Notes - PPIs may be used to protect the gut with chronic NSAID use, but consider side effects of chronic PPI (decreased bone density and increased infection risk)
dipyridamole - MOA, warnings (1), side effects (1), notes (1)
MOA - inhibits uptake of adenosine into the platelets and increases cAMP levels, which inhibits platelet aggregation
Warnings - hypotension due to vasodilatory effects
Side effects - headache
Notes - not interchangeable with individual aspirin and dipyridamole
clopidogrel - MOA, dosing, boxed warning (1), contraindications (1), other warnings (3), notes (1)
MOA - prodrug that irreversibly inhibits P2Y12 ADP-mediated platelet activation and aggregation
Dose - 75mg daily
Boxed warning - prodrug metabolized by CYP2C19. Poor metabolizers have higher CV events.
Contraindications - serious bleeding
Warnings -
- bleeding risk so stop prior to surgery
- do not use with omeprazole/esomeprazole due to CYP219 interaction
- may cause thrombotic thrombocytopenia (TTP)
Note - drug of choice if contraindication or allergy to ASA
What is the treatment for intracerebral hemorrhage (ICH)?
mostly supportive treatment
- Reverse anticoagulaatns
- Treat seizures
- Decrease intracranial pressure (ICP): elevation of head of bed, hyperosmolar therapy with hypertonic saline or mannitol, craniotomy
Mannitol - dosage form, contraindications (4), warnings (1), notes (2)
Injection
Contraindications -
- severe renal disease (anuria)
- severe hypovolemia
- pulmonary edema or congestion
- active intracranial bleed (except during craniotomy)
Warnings -
- CNS toxicity
Notes -
- inspect for crystals
- use a filter for administration
What is the common cause of a subarachnoid hemorrhage (SAH)? What is the treatment for acute SAH?
Cause: Usually happens due to a ruptured cerebral aneurysm
Treatment
- Reverse anticoagulation, treat seizures
- Surgical intervention (clipping, coiling)
- Prevent cerebral artery vasospasms (most likely to occur 3-21 days after the bleed): PO nimodipine 60mg Q4H for 21 days
Nimodipine - drug class, dosing, boxed warnings (1), contraindications (1), side effects (1), notes (1)
Drug class - DHP CCB that is more selective for cerebral arteries due to increased lipophilicity
Dosing - 60mg PO Q4H x21 days
Boxed warnings
- do NOT administer IV: death has occurred
Contraindications
- Strong CYP3A4 inhibitors (azoles, protease inhibitors, clarithromycin) increase risk of significant hypotension
(strong CYP3A4 inducers [rifampin, carbamezapine, phenytoin, St. John’s wort] can decrease levels -> avoid)
Side effects - hypotension
Notes -
- label oral syringes as “for oral use only” or “not for IV use”
