3- Cerebrovascular Disease Flashcards
What is the leading cause of disability and 5th leading cause of death in the US?
CVA
A stroke is the acute neurologic injury that occurs as a result of one of which 2 pathologic processes?
Hemorrhage
Ischemia (more common)
What are the 3 causes of brain ischemia?
Thrombosis, embolism (ex. a fib, carotid artery plaques), hypoperfusion
Pt presents with sxs of brain dysfunction that are diffuse and nonfocal, bilateral neurologic signs, and evidence of circulatory compromise with hypotension. You are concerned for ischemic stroke caused by what?
Hypoperfusion
What type of CVA is secondary to low flow states from vessel overlap or systemic hypotension?
Watershed infarcts
What type of hemorrhage is bleeding directly into brain tissue?
Intracerebral
(aka parenchymal)
What type of hemorrhage is bleeding into the CSF that surrounds the brain and spinal cord?
Subarachnoid
CT of pt with suspected CVA shows a hypodense (darker) area of brain tissue. Are you concerned for hemorrhagic or ischemic stroke?
Ischemic
CT of pt with suspected CVA shows a radiopaque/white area. Are you concerned for hemorrhagic or ischemic stroke?
Hemorrhagic
A large vessel stroke can be within either the anterior circulation or posterior circulation. What vessels contribute to the anterior circulation? (4)
- Carotid arteries (extra/ intracranial)
- Middle cerebral artery (MCA)
- Anterior cerebral artery (ACA)
- Anterior communicating artery (AComm)
A large vessel stroke can be within either the anterior circulation or posterior circulation. What vessels contribute to the posterior circulation? (4)
- Vertebral arteries (extra/ intracranial)
- Posterior cerebral artery (PCA)
- Posterior inferior cerebellar artery (PICA)
- Basilar artery
What is the most common affected vessel in a CVA?
Middle cerebral artery
Pt presents with contralateral hemiplegia/ hemianaesthesia (weakness/ numbness) of the face + arm > leg. You note contralateral homonymous hemianopia and a faze preference to the ipsilateral side. Where are you concerned for CVA?
Middle cerebral artery (MCA)- affects frontal, temporal, parietal lobes
(large vessel, anterior circulation)
What will be noted if dominant vs non-dominant hemisphere is involved in CVA of MCA? (large vessel, anterior circulation)
Dominant: global aphasia
Non-dominant: hemineglect
Pt presents with contralateral hemiplegia/ hemianaesthesia (weakness/ numbness) of the leg > arm. You note profound abulia or perseverating speech. Where are you concerned for CVA?
(abulia- delay in verbal/ motor response)
Anterior cerebral artery (ACA)- affects frontal pole/ lobe
(large vessel, anterior circulation)
Pt presents with visual field defects due to impingement of cranial nerves. Where are you concerned for CVA?
Anterior communicating artery (AComm)
(large vessel, anterior circulation)
Pt presents with contralateral homonymous hemianopia and reduced light touch/ pinprick sensation. Where are you concerned for CVA and why is this type of CVA concerning?
Posterior cerebral artery (PCA)- affects occipital cortex
Concerning b/c may go unnoticed by pt due to minimal motor involvement
(large vessel, posterior circulation)
Pt presents with ipsilateral loss of facial pain/ temp sensation with contralateral loss of these senses over the body +/- vertigo, vomiting, nystagumus, ipsilateral ataxia, hoarseness, dysarthria, dysphagia, hiccupts, and ipsilateral Horner’s syndrome. Where are you concerned for CVA?
(Horner’s- ptosis/ miosis w/o anhidrosis)
Posterior inferior cerebellar artery (PICA)- affects lateral medulla
(Wallenberg’s/ lateral medullary syndrome)
(large vessel, posterior circulation)
Pt presents with quadriplegia and facial/ mouth/ tongue weakness, preserved consciousness, and preservation of vertical eye movements/ blinking. Where are you concerned for CVA?
Basilar artery
(sxs = “locked-in syndrome”)
(large vessel, posterior circulation)
What type of CVA is due to occlusion of one of the small, penetrating branches of the Circle of Willis, middle cerebral artery stem, or vertebral/ basilar arteries and is commonly a/w chronic HTN?
Small vessel (“Lacunar”) stroke
What may be necessary during initial assessment in CVA due to increased ICP?
Intubation
(if decreased respiratory drive/ decreased level of consciousness)
What is usually elevated in patients with acute stroke and often represents an appropriate response to maintain brain perfusion?
MAP
When should you start treating BP for ischemic stroke?
> 220/120
What are the BP guidelines for hemorrhagic stroke?
Keep < 160/ 90, but systolic > 140
What is the most important hx question when evaluating for CVA?
When did the sxs start?
(should also r/o problems that could mimic stroke, ex. hypoglycemia)
What is the 1st dx test in the assessment of stroke?
Non-contrast CT brain
Does a CT for a hemorrhagic or ischemic CVA have the potential to be normal?
Ischemic (takes time to be evident on CT)
When would an ischemic CVA be clinically diagnosed?
Sxs present for < 6 hrs
Affected area is small
Located in area of brain not well seen on CT
In addition to ICU admission, what is the tx for ischemic CVA if brain CT returns showing no bleed?
Full dose aspirin w/i 48 hrs
tPA w/i 60 minutes- if sx onset < 4.5 hours and BP must be ≤ 185/110
If CT of pt with suspected ischemic CVA shows ischemia (acute hypodensities), what tx is contraindicated?
tPA- sxs have been going on too long
What tx might be utilized for patients with acute ischemic stroke caused by an intracranial large artery occlusioin in the proximal anterior circulation?
Mechanical thromebectomy (if w/i 6 hrs of sxs onset)
In addition to ICU admission and immediate neurosurgery consult, what is the tx for hemorrhagic CVA?
D/c + reverse anticoagulants/ antiplatelet drugs
Lower ICP
Control BP (~160/90)
Antiepileptics (prn)
(methods for lowering ICP: elevate head of bed, analgesia, sedation, osmotic diuretics, drain CSF (bolt), NM blockade, hyperventilation)
In the management of hemorrhagic CVA, what are the indications for immediate surgical consult/ removal of hemorrhage?
Cerebellar hemorrhages > 3cm
Deteriorating/ brain stem compression
Hydrocephalus
What is included in secondary prevention of CVA?
Tx underlying + antiplatelets for ischemic
TIA is defined as a transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischemia WITHOUT what?
(sxs do not have to be focal)
Acute infarction (tissue damage)
TIA places pt at increased risk for stroke. What testing/ therapy lessens this risk?
Hospital admission, EKG, carotid US, lipid lowering/ antihypertensive meds, diet/ lifestyle mod, start daily aspirin therapy +/- CTA of head and neck
If a pt is on a daily aspirin + meds for controllable RFs and still suffers a TIA, discussion with neurology might indicate addition of what?
Clopidogrel or aspirin-extended-release dipyridamole
Pt w/ no hx of HAs presents with sudden onset (“thunderclap”) worst HA of their life (WHOL) and has become somnolent. What are you concerned for and what urgent imaging is indicated?
Subarachnoid hemorrhage (SAH)
Non-contrast brain CT
Most SAHs are caused by what?
Ruptured saccular aneurysms
(although most aneurysms do not rupture)
What are 2 more important RFs a/w SAH?
Hx of polycystic kidney disease
Smoking (biggest preventable RF)
What is the pathogenesis of SAH?
Rupture of aneurysm releases blood into CSF leading to increased ICP
What are the common complications a/w SAH that contribute to mortality?
Re-bleeding (w/i 1st day)
Vasospasm (no earlier than day 3 and peaks at day 7)
If RBCs are present in CSF, there is either true SAH or traumatic tap. How are these differentiated?
True SAH- RBC #’s stay the same from 1st - 4th tube
Traumatic tap- RBC #’s decreased from 1st - 4th tube
What is the most sensitive indicator of SAH?
Xanthochromia- pink or yellow tint of CSF
(compare vial of CSF with vial of plain water)
Pt with suspected SAH has normal non-contrast CT brain results. What should be your next step?
LP +/- CTA of COW
In addition to ICU admission, control of ICP, seizure prophylaxis, and d/c blood thinners, what is the management for SAH?
Analgesia (prevent rebleeding)
Transcranial doppler (TCD) US (monitor for vasospasm)
IV fluids + nimodipine (prevent vasospasm)
Definitive: surgical clipping or endovascular coiling
Are the consequences of traumatic SAH or spontaneous SAH generally more severe?
Spontaneous
