Lecture 8: Cerebrovascular Disease Flashcards
How quickly does cell death and irreparable damage occur in CVA?
Within 5 minutes of losing blood flow.
What are the 3 primary arteries of the brain?
- Anterior cerebral artery (ACA): medial/frontal, anterior basal ganglia
- Medial cerebral artery (MCA): lateral frontal/parietal, anterior and lateral temporal, remaining basal ganglia
- Posterior cerebral artery (PCA): Thalamus, brainstem, posterior/medial temporal, occipital.
MCA is most commonly occluded artery
What supplies the cerebral arteries?
- Penetrating vessels
- Vertebrobasilars
- Internal carotids
What is the leading cause of disability in the US?
Stroke ):
MC after 65 and in men.
What is the MC type of stroke?
Ischemic stroke
4 out of 5 strokes are ischemic
Describe an ischemic stroke.
Acute occlusion of intracranial vessels leading to a reduction of blood flow, resulting in cell hypoxia and loss of neurologic function.
What is the penumbra?
Surrounding tissue around the ischemic core of a stroke, which can remain viable for HOURS after stroke.
What is the ischemic core?
Area of complete loss of blood flow, resulting in death of that area in 4-10 minutes.
What are the 2 pathologic etiologies that can result in ischemic stroke?
- Thrombotic: related to ruptured atherosclerotic plaques leading to platelet activation.
- Embolic: embolus forming at an extracranial source. (think AFIB)
What risk factors are specific to younger patients in CVA?
- TBI
- Coagulopathies
- Illicit drug use (cocaine)
- Migraines
- OCP use
- Covid
What two processes result from the rupture of a cerebral artery?
- Cerebral ischemia
- Increased ICP
What are the 2 types of hemorrhagic strokes?
- Intracerebral hemorrhage (ICH) usually due to prolonged uncontrolled HTN
- Subarachnoid hemorrhage (aneurysms, AV malformation, trauma)
What are the risk factors for hemorrhagic strokes?
- Advanced age
- HTN
- Anticoag use
- Previous stroke hx
- Alcohol
- Illicit drug use
What is the stroke mnemonic?
- Balance
- Eyes
- Face
- Arm
- Speech
- Time
Please know this!!!!
Which stroke typically presents worse?
Hemorrhagic stroke
What is the MC S/S of a hemorrhagic stroke?
- Thunderclap headache
- Worst HA of their life or 10/10
What is the most important historical thing in stroke workup?
Knowing the onset!!!!!!!!!!!
What two drug types would be of concern in workup for stroke?
Oral hypoglycemic agents or anticoagulants
What skin findings are sometimes seen in stroke?
- Infective endocaritis: Petechiae, janeway lesions, oslers
- Cholesterol emboli: livedo reticularis/gangrene
- Bleeding diathesis: Purpura, ecchymoses
- Recent surgery scars
What are the 7 aspects of the NIH Stroke scale?
- Mental status/LOC
- Vision (confrontation)
- Motor function
- Cerebellar function (finger nose, heel shin)
- Sensory function
- Language (ability to describe and perform a task)
- Neglect
What are the severities of the NIHHS?
What are the class I indications for acute stroke workup?
- Fingerstick BG
- CT brain WITHOUT contrast (25 mins within arrival)
Why is a CT brain without contrast the first-line imaging modality for stroke?
- High sensitivity to rule out hemorrhage
- Rules out other mimicking conditions
- Easy to perform and no prep needed
What does a SAH look like on CT?
Floppy starfish
per elkins
What special labs are indicated in stroke workup?
- Direct factor 10a activity assays (if on a 10a inhibitor and candidate for thrombolytic therapy)
- Troponin (r/o MI)
What lab order should be ordered with caution in a patient we are considering for fibrinolytic therapy?
If you want an ABG, the site will be more likely to bleed.
At what point do we supplement o2 in a stroke patient?
To get above 94%
What 3 conditions would we elevate head to 30deg?
- Increased ICP
- Aspiration
- Cardiopulmonary decompression or O2 desatting
Otherwise, keep supine.
What temp is concerning in stroke and what do we give?
- Above 100.4
- Tx with acetaminophen via suppository or IV
- Surface cooling
When do we treat hypoglycemia and hyperglycemia in stroke?
- Hypoglycemia: only treat if under 60. (class I)
- Hyperglycemia: only treat if over 180 (class 2a)
How do we reverse warfarin in hemorrhagic strokes?
Vit K + 4-factor prothrombin complex concentrate (PCC)
How do we reverse dabigatran/pradaxa in hemorrhagic stroke?
Activated charcoal or praxbind or PCC
How do we reverse a factor 10a inhibitor with hemorrhagic stroke?
Activated characoal vs Andexxa vs PCC
xarelto, eliquis, arixtra, savaysa
How do manage hypotension in ischemic stroke?
IV fluids only
How do we manage hypertension in ischemic stroke?
Goal is LESS THAN 185 SBP and DBP LESS THAN 110 (class 1)
1. IV nicardipine
2. IV clevidipine
3. IV labetalol
All first-line indications PRIOR to tPA
If a patient is already NOT a candidate for tPA for ischemic stroke, when do we treat HTN? Caveats?
DO NOT TREAT until >220 SBP or DBP > 120
- Evidence of end organ damage
- Comorbid or complicating diseases
Avoid lowering more than 15% in first 24 hours
End organs include brain, eyes, heart, and kidneys.
How do you titrate BP for intracerebral hemorrhagic stroke?
- If between 150-220 SBP, then titrate slowly to 130-140. (Class 2a)
- If SBP > 220, no evidence but common practice to treat it down to the same.
Same antiHTNs.
What is the goal BP in SAH?
SBP < 160 or MAP < 110 is the reasonable recommendation (labetalol, nicardipine, enalapril)
What drug prevents vasospasm in SAH?
Nimodipine for 3 weeks.
What is the FDA-approved drug for tPA?
Alteplase
What must be done prior to tPA administration?
- Inclusion criteria MUST BE MET (class 1)
- Only glucose needs to be assessed prior to initiation
- Informed consent MUST BE obtained
What is the inclusion criteria for rTPA?
- Clinical diagnosis of ischemic stroke causing measurable neurologic deficit (AKA CT scan to r/o hemorrhage)
- Symptoms must be within 4.5 hours before beginning, aka must know Last known normal
- Age > 18
MUST KNOW!
What are the management steps for tPA administration?
- Stop infusion and get CT if HA, N/V, acute HTN, or deterioration
- Admit/transfer to ICU
- Neurochecks
- BP < 180/105
- no NG tubes/catheters
- CT at 24 hours post-tpa
What are the two main complications of tPA and the treatment for them?
- Acute bleeding = cryoprecipitate or TXA
- Angioedema = IV methylpredinisolone, diphenhydramine and famotidine and maybe EPI
What is the alternative treatment for ischemic stroke?
Endovascular mechanical thrombectomy, primarily indicated for large artery occlusion in anterior circulation via MRA/CTA with small infarct core and no hemorrhage
Within 24 hours!
Big clot in anterior with a small core
What are the main complications that occur with an intracerebral hemorrhage? (ICH)
- Hematoma = evacuate moderate to large or for large intraventricular extensions.
- Large ICH = craniotomy vs craniectomy
What are the neurologic complications of stroke in general?
- Cerebral edema (worse the bigger the infarct), treated via mannitol and fluid restriction and decompressive craniectomy.
- Increased ICP (MC in hemorrhagic) elevate and give osmotic diuretics like mannitol or hypertonic saline
- Hydrocephalus (monitor for worsening HA and progressively impaired neurological testing), need CT/MRI of enlarged ventricles and consider shunt placement.
- Seizures (MC in hemorrhagic), use EEG. Primary prophylaxis only for impaired consciousness and evidence of seizure activity on EEG or hx of seizures.
How do you treat and prevent seizure in stroke?
- Acute seizure = lorazepam
- Prevention = fosphenytoin
fosp = For Prevention
How do you prevent primary strokes?
Screen and control modifiable risk factors only
What is the main thing to treat in secondary stroke prevention?
HTN
In what kind of stroke type does statin therapy help with?
Ischemic stroke
What medication is recommended for secondary stroke prevention post ischemic stroke?
- If tPA was used, start ASA 24-48 hours after tPA
- If tPA was NOT USED, start ASA and Plavix within 24 hours
21 days
When is anticoagulant therapy indicated in post-stroke management?
Any patient that had a potential cardiac source of embolism. (MC: AFIB)