Chapter 33: Stroke Flashcards
How is acute ischemic stroke (aka, a non-cardioembolic stroke) caused
By a thrombus that forms during a cerebral atherosclerotic infarction
How does a cardioembolic stroke occur
when an embolus forms in the heart and travels to the brain
A common cause of cardioembolic stroke
AFib
Risk factors for stroke
HTN (most important) AFib Gender (F > M) Ethnicity (↑risk in AA) Age > 55 years Atherosclerosis Diabetes Prior stroke or TIA Smoking Dyslipidemia Patent Foramen Ovale (PFO) Sickle Cell Disease
What is a TIA
caused by a temporary clot, or block of blood flow, in the brain. Symptoms are the same as stroke, but disappear on their own within minutes to a few hrs; there is NO permanent damage
-Seek immediate medical attention: TIAs are often a warning for a future full stroke
Signs and symptoms of stroke
- remember: act F.A.S.T*
- Face: ask the person to smile. Does one side of the face droop or is it numb? Is the smile uneven?
- Arms: ask the person to raise both arms. Does one arm drift downward?
- Speech: ask the person to repeat a simple sentence. Are the words slurred? Is the sentence repeated correctly?
- Time: if the person shows any of these sx, even if they go away, call 911 immediately
What is performed in stroke patients within 20 min of arrival to ED
Brain imaging, using CT
Immediate goal for ischemic stroke
Restore blood flow to the ischemic area of the brain to obtain complete neurological recovery
MOA of alteplase
recombinant tissue plasminogen activator (tPA) that binds to fibrin in a thrombus and converts plasminogen to plasmin, resulting in fibrinolysis
What is the ONLY fibrinolytic drug that is used in acute ischemic stroke
Alteplase
Patients are candidates for alteplase if a clot is confirmed on brain imaging and the following criteria for timing are met:
- Can be administered within 3 hours of symptom onset
- It can be administered within 4.5 hours of symptom onset in select patients (not FDA-approved)
- It can be administered within 60 min of hospital arrival (door-to-needle time)
Alteplase CI
- Active bleed (e.g., internal bleed, ICH)
- Conditions or labs that increase risk of bleed (e.g., severe HTN, INR > 1.7)
- Drug interactions with bleeding risk (e.g., anticoagulants)
- Severe, uncontrolled HTN (BP > 185/110 mmHg)
- History of recent stroke
Alteplase brand name
Activase
Max dose of alteplase in ischemic stroke
90 mg
What must be excluded before using alteplase
intracranial hemorrhage
Alteplase SE
Major bleeding (e.g., ICH)
ASA __-__ mg PO within __-__ hrs after stroke onset is recommended to prevent early recurrent stroke
162 – 325
24-48
Which antihypertensive drug classes have the best evidence for stroke risk reduction
ACEi and thiazide diuretics
What is the goal BP for ischemic stroke
< 130/80 mmHg
What statin intensity should be used in secondary prevention of stroke
High-intensity
For patients with non-cardioembolic ischemic stroke or TIA, what drug is recommended to reduce the risk of recurrent stroke
ASA (or clopidogrel if ASA is CI)
Combo of ASA and clopidogrel can be initiated within 24 hrs of a minor ischemic stroke & continued for 21 days. This combination should not be used long-term for secondary prevention of stroke or TIA as it increases the risk of ____
hemorrhage (NOTE: this is different for ACS - in ACS, DAPT is used for 12 months & can be continued if the pt is tolerating and are not high risk for bleeding following stent placement)
T/F: In patients who have an ischemic stroke or TIA while taking ASA, there is an added benefit to increase the ASA dose
False - there is no added benefit
What is the MOA of dipyridamole
inhibits the uptake of adenosine into platelets and increases cAMP levels, which inhibits platelet aggregation
Aspirin dosing in stroke
50-325 mg daily
Aspirin ER capsule brand name
Durlaza
Aspirin DR tablet brand name
Yosprala
ER dipyridamole/aspirin brand name
Aggrenox
ER dipyridamole/aspirin warnings
hypotension
ER dipyridamole/aspirin SE
headache
Clopidogrel dosing in stroke
75 mg daily
Clopidogrel should be stopped __ days prior to elective surgery
5
Clopidogrel should be avoided with which 2 drugs
omeprazole and esomeprazole
What should be done in patients with intracranial hemorrhage who are anticoagulated
reversal of the anticoagulant should be considered
What should be done in ICH if there is clinical evidence of seizures
They should be treated but ppx anticonvulsant meds should not be used
How is ICH treated
elevate the head by 30 degrees and use mannitol or hypertonic saline
MOA of mannitol
Produces osmotic diuresis. Reduces ICP by withdrawing water from the brain
Mannitol formulation
injection
Mannitol CI
severe renal disease
How does acute subarachnoid hemorrhage present
Severe headache
Cerebral artery vasospasm can occur __=__ days after the bleed in SAH, causing delayed cerebral ischemia
3-21
Which drug & route is used to prevent vasospasm in SAH
oral nimodipine
Nimodipine MOA
DHP CCB that is more selective for cerebral arteries d/t increased lipophilicity
Nimodipine BW
Do not administer IV or by any other parenteral routes; death and serious life-threatening AE have occurred when contents of the capsules have been injected parenterally
Nimodipine SE
Hypotension
If nimodipine capsules cannot be swallowed, what can be done
contents can be withdrawn with a parenteral syringe, then transferred to an oral syringe that cannot accept a needle; label oral syringes “For Oral Use Only” or “Not for IV Use”