Cerebrovascular Disease Flashcards
what is a stoke (CVA)
An insult to the CNS occurring on a primary vascular basis.
The insult can occur in the cortex of the brain, subcortical structures, brainstem, cerebellum or spinal cord.
what are the two types of strokes
primary ischemic
primary hemorrhagic
What is the percent of ischemic strokes?
80%
Cerebral embolism=30%
large artery thrombosis=30%
small artery thrombis (lacune) 20%
what percent of strokes are hemorrhagic?
20%
Intacerebreal hemorrhage-14%
Subarachnoid hemorrhage=6%
what is the epidemiology of stroke
CVA affects 500,000 americans 3rd leading cause of death Men>Women Blacks>whites Stroke doubles for each decade beyond 55
what are the factors that increase risk of CVA?
Male, A. Fib, Hx of TIA/RIND black, HTN, Genetic predisposition, age>55 Diabetes, PVD, Smoking, hyperlipidemia Sickle cell Dz, Hx of CVA, Bruit or carotid stenosis Valvular heart dz hypercoaguable state Polycythemia
what are the risk factor of CVA in younger population
MVP Patent foramen ovale Migranious infarction Hypercoaguable state Illicit drug use AVM/Aneurysm
What will be the presentation of the patient with CVA Hemispheric stroke
HA (most likely with hemorrhagic stroke or SAH)
Alteration in consciousness
speech disturbance
Visual field deficits-homonymous deficit
cognitive impairment
contralateral motor deficit/sensory deficit
what is the presentation of the patient with CVA (brainstem/ cerebellar stroke)
Dyarthria-difficulty with you motor part of speech controlling
Dysphagia-trouble swallowing
Ataxia-lack of voluntary muscle movements
Diplopia
Vertigo
Nystagmus
Nausea
what will strokes in a middle cerebral artery territory?
In dominant hemisphere would include aphasia / dysphasia
Contralateral motor weakness (central facial + arm > leg)
what will a stroke in a anterior cerebral artery territory?
Contralateral leg > arm or face Speech may be spared
what will a stroke in a posterior cerebral artery territory?
Contralateral homonymous hemianopsia
Speech unaffected – no weakness likely (motor cortex, speech area too far from site of CVA)
Vertebrobasilar artery stoke at base of brain (posterior cerebral artery) territory would cause?
bilateral blindness
what will a lacunar stroke look like?
Paresis affecting face / arm / leg equally with no sensory loss (because of predilection for internal capsule – resulting in pure motor stroke)
Lacunar stroke (thalamus)
pure sensory stroke
internal capsule stroke will show
pure motor stroke
what is the berg balance scale?
a tool used for determining pts who can safely ambulate vs W/C
what is the scale for berg balance scale and what does each range indicate for a fall risk?
scale 0-56
0-20 high fall risk
21-40 medium fall risk
41-56 low fall risk
What should you do when evaluate a stroke victim?
assess for airway and breathing
Blood loss is not an issue in and of itself for cerebral bleeds – pts will not exsanguinate
Evaluate for level of consciousness
Obtain Hx from pt or family
Cognitive function/language
Evaluate CN/language/weakness/sensory/DTR/babinski/cerebellar
which is more valuable diagnostic imaging for CVA CT or MRI?
CT is more valuable than an MRI
Do non-contrast CT 1st in case there is a hemorrhagic stroke
Then use an EKG to look for cardiac source for embolic stroke
what do carotid and vertebral duplex scan look for?
embolus or stenosis
what is the gold standard for thrombosis, stenosis, arterial dissection, vascular anomalies?
cerebral arteriography
what are CI for TPA?
hemorrhagic stroke large infarct >3hrs since onset any question of coagulopathy recent major surgery prior stroke severe HTN/metabolic disturbance
what is the most common cause of Intracerebral hemorrhage (ICH)?
Hypertension
where are the most common locations for ICH?
basal ganglia
thalamus
cerebellum
pons
what is the management of ICH?
similar to ischemic stroke
must address intracranial pressure- can be lowered by intubating pt and placing on a vent and keep resp rate set at a point to maintain PCO2 between 25 and 30 this will diminish cerebral blood flow to a point where it will lower ICP
What Meds are used in management of ICH?
mannitol- potent osmotic diuretic that reduced cerebral edema (has rebound effect)
evacuation of the hematoma may be indicated
control BP aggressively
what is subarachnoid hemorrhage?
bleeding into the subarachnoid space
Very common etiology of SAH is head trauma
common with aneurysm or AVM
how is subarachnoid hemorrhage confirmed?
Lumbar puncture that will show blood CSF
what are the sign of subarachnoid hemorrhage?
similar to meningitis due to meningeal irritation from blood: stiff neck (nuchal rigidity) photophobia severe HA low grade fever
what are the complications associated with aneurysm’s?
Rebleed- clot forms in wall or aneurysm in those pts who survive
body will tend to break down clot in about 10-14days so this is when risk for rebleed is the highest
cerebral edema/ischemia and vasospasm
hydrocephalus
what is a TIA
precursor to stroke
embolic phenomena- similar to stroke except the embolus moves on before infarction can occur- so pts symptoms are of ischemia (brain equivalent of angina in a way)
what is the difference between TIA and CVA?
TIA resolves with no deficit
CVA has neurological deficit
CT of TIA is negative for infarction
CT for stroke is + for infarction
what is the most common presenting symptom of TIA in the anterior circulation?
transient monocular blindness called amaurosis fugax
often described as a curtain
what are carotid TIA symptoms?
amaurosis fugax aphasia hemiparesis hemisensory deficit homonymous hemianopsia
what are TIA symptoms for posterior curculation
ataxia bilateral visual loss quadripareiss perioral numbness vertigo/syncope/dysarthria/diplopia/nausea/dysphagia homonymous hemianopsia
