Cerebrovascular accident (stroke or brain attack) is the 5th most common cause of death in Canada. The most effective way to decrease this burden is with prevention
Stroke occurs when there is ischemia to a part of the brain OR hemorrhage into the brain that results in death of brain cells
Functions controlled by the part of the brain with tissuedeath (left or right) are lost or impaired (eg: movement, sensation, emotions). The severity of the loss varies according to location and extent of the brain involved
The most common location for stroke is the middlecerebralartery. Other locations include the internalcarotidartery or the vertebralartery.
Non modifiable factors
advanced age
gender
ethnicity
family history
prior TIA or stroke
Modifiable risk factors:
HTN
diabetes mellitus
atrial fibrillation
dyslipidemia
carotid stenosis
oral contraceptive use
smoking
Transient ischemic attack (TIA) is a transient episode of neurologicaldysfunction without acuteinfarction (cell death) of the brain. Symptoms typically last less than an hour but is a big risk factor for strokes
Types of stroke
ischemic: can be thrombotic (clot formed in brain) or embolic (clot travels to brain)
hemorrhagic (bleeding in brain)
Thrombotic strokes occur when a thrombus (blood clot) forms in diseased and narrowed blood vessel in the brain. It is often associated with HTN or diabetes
Embolic strokes occur when an emboluslodges in and occludes a cerebral artery. Heart conditions associated with emboli are atrialfibrillation and valvularprostheses
Hemorrhagic strokes result from bleeding into the brain tissue itself or into the subarachnoidspace or ventricles. This happens through a cerebral artery aneurysm that bursts and releases blood
Hemorrhagic strokes are classified according to where the bleed is located. For examples a subarachnoid stroke is a bleed over the arachnoid meninge.
Stroke clinical manifestations
hemiplegia (paralysis) or hemiparesis (weakness)
impaired swallowing or gag reflex = dysphagia
numbness of face, arm or leg
visual disturbance = hemianopsia (loss of half the visual field)
The left side of the brain sees te right side of the world meaning that if the left side of the brain is damaged, your rightvisualfield is affected
Stroke patients may experience aphasia (understanding) or dysarthria (speech) when a stroke damages the dominanthemisphere of the brain
Dysarthria: disturbance of muscularcontrolofspeech
Intellectual clinical manifestations
difficulty controlling their emotions
exaggerated or unpredictableemotional responses
impairedmemory or judgement
spatial perceptual: difficulty judgingdistances or neglect
Stroke pts may initially have urinary and boweleliminationproblems
Motor deficits are contralateral (opposite) because motor pathways cross at the brainstem. A stroke affecting the left side of the brain will lead to motordeficits on the right side