Stroke Flashcards
Stroke
Apoplexy-struck down with violence.
1599: stroke first used to describe apopletic seizure. Greek struck by hand of God.
Hippocrates: 460-370BC
out of favour-CVA
“a neurological deficit or cerebrovascular cause that persists beyond 24 hours or is interupted by death in 24 hours”
Prevelance
Every 10 minutes #1 cause of disability #3 cause of death 50,000 Canadians in hospital/year with stroke 16,000 die/year 3.0 billion dollars/year
Acute Ischemic Stroke
Thrombo-embolism is a clot that blocks blood flow-ischemia.
Spontaneous Intracranial Hemorrhage
Intracerebral Hemorrhage is 10-15% of stroke
Small artery rupture
Aneurysmal subarachnoid hemorrahge-5-10% of stroke
Visualizing Stroke
- CT Scan-ischemic infarct, intracerebral hemorrhage, subarachnoid hemorrhage.
Signs of a Stroke
Hypertension, headache, left side paralysis
- unilateral wekaness or numbing
- Difficulty speaking/understanding
- Loss or change in vision
- Severe and unusual headache
- Loss of balance/dizziness
Language Disorders
- Wernickes-word salad, no meaning
- Brocas-no production-no syntax
Dysarthria-do they slur?
Neglect/Hemi-inattention
Right Parietal lobe lesion-usually non dominant side effected
Sub-Cortical Anatomy (white matter)
Internal Capsule-absolutely paralyzed because face, arm and leg fibres travel through there.
Contralateral weakness-brain wiring
Arterial Supply of Brain
Circle of Willis-Protection from stroke
Vertebral artery, internal carotid artery, aorta
Anterior Circulations
Internal carotid artery-2/3 of cerebral artery. Supplied by middle cerebral artery and anterior cerebral artery.
Middle Cerebral Artery
Supplies lateral surfaces of hemisphere and deep structures
Basal ganglia and subcortical white matter.
Contralateral face and arm weakness.
Dysphasia-left hemisphere. Neglect-Right hemisphere
Anterior Cerebral Artery
Supplies the medial surface of hemisphere. Contralateral leg weakness and or numbness.
Large Artery/ Cortical Stroke
Controlateral weakness, neglect (RH), aphasia/dysphasia (LH), contralateral visual loss
Subcortical/ lacunar stroke
Deep branches of any cerebral artery. Most common symptom is contralteral weakness
Subcortical Stroke (white matter)
Contralateral weakness effects face, arm and legs
Posterior Circulation
Vertebral and basilar arteries supply posterior and medial regions of hemispheres brainstem, diencephalon, cerebellum. Major branches: posterior cerebral artery and cerebellar arteries
Brainstem Stroke
Cranial nerves and wiring downstream from internal capsule. Lacunar syndrome. Weak and ataxic on the contralateral side.
Posterior Cerebral Artery Stroke
Contralateral hemianopsia-blindness on one side of the visual space.
Pons Stroke
Locked in syndrome-only stroke with bilateral symptoms. Trouble with ballistic movements
Transient Ischemic Attack
Resolves by itself in 24 hours of onset (stroke and TIA are continuum).
Warning sign for major stroke
50% of all TIAs are associated with permanent damage. >1 hour symptoms usually.
Thrombo-embolism-Imaging
Magnetic Resonance Angiogram
Sources of Emboli causing a Stroke
- The heart
- Arteries in neck
- Arteries in brain itself (large and small)
cardio-embolsim stroke-atrial fibrillation.
Carotid artery atherosclerosis-internal carotid artery. Atherosclerotic. Plque, CT angiogram, intracranial anthrosceloritc disease.
Cerebral Ischemia
Insufficient blood supply (and therefore oxygen and glucose) to meet the metabollic demands of the brain.
Ischemic Penumbra: normal grey matter(65%), protein synthesis impaired (55%), electrical failure (20%), inactive penumbra tissue. K+ release and cell death (10%).
Target treatment: restore normal blood flow. Loss of blood and oxygen to stop making ATP. Na+/K+ pump. Keep water in cell so then water moves into the cell with sodium if they fail.
Thrombo-embolism-thrombolysis-tissue plasminogen activator (tPA)
Hemorrhagic Shock
ICH is the second most common stroke type. 10-20%
more common is asian and africans
size matters
intitial level of consciousness and hematoma volume predicts death. Drawsy=worse.
Amyloid can make interacerevral arteries brittle and prone to rupture.
No treatment yet
Developmental Aneurysms:
1. Hypertension
2. Smoking
3. Family History-2 or more 1st degree relatives.
Subarachnoid Hemorrhage
Bleeding into subarachnoid space
Surgical clip or endovascular coil
Preventing Stroke
- High blood pressure treament-drugs.
- Smoking
- Aspirin (low dose)
- Anticoagulant-Warfarin or other newer drugs-only for patients with atrial fibrillation-cardioembolic stroke
Low blood pressure=less stroke.
Platelet activation-inhibited by asprin.
