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CEREBRAL VASCULARACCIDENT
Raja
Nursing Instructor
Acknowledgement: Badil31/03/2016
Objectives:
Define Cerebro vascular Accident (CVA)
Describe the causes of CVA
Understand the pathophysiology of CVA
List the sign and symptoms of CVA
Define Cerebro vascular Accident (CVA)
Describe the causes of CVA
Understand the pathophysiology of CVA
List the sign and symptoms of CVA
Cerebral regulation
The blood flow to the brain is maintained at
approximately 750 mL/minute or one sixth of the
resting cardiac output.
The blood flow to the brain is maintained at
approximately 750 mL/minute or one sixth of the
resting cardiac output.
Review of Cerebral Circulation
Blood is supplied to the brain by two major pairs ofarteries
Internal carotid arteriesVertebral arteries
Blood is supplied to the brain by two major pairs ofarteries
Internal carotid arteriesVertebral arteries
Carotid Arteries supply
Carotid arteries branch to supply most of the
Frontal, parietal, and temporal lobes
Basal ganglia
Diencephalon (Part of the brain that includes)
Thalamus
Hypothalamus
Carotid arteries branch to supply most of the
Frontal, parietal, and temporal lobes
Basal ganglia
Diencephalon (Part of the brain that includes)
Thalamus
Hypothalamus
Vertebral arteries
Vertebral arteries join to form the basilar artery, which
supply the:
Middle and lower temporal lobes
Occipital lobes
Cerebellum
Brainstem
Part of the diencephalon
Vertebral arteries join to form the basilar artery, which
supply the:
Middle and lower temporal lobes
Occipital lobes
Cerebellum
Brainstem
Part of the diencephalon
Carotid artery
Review of Cerebral Circulation
Cerebrovascular Accident
It is refereed as
stroke
Brain attack
Loss of brain function
More than 24 hours
Ischemia is inadequate blood flow
It is refereed as
stroke
Brain attack
Loss of brain function
More than 24 hours
Ischemia is inadequate blood flow
Conti….
Brain attack (Stroke) occurs when there is ischemia
to a part of the brain that results in death of brain
cells
Stroke is the syndrome of acute focal neurologic
deficit from a vascular disorder that injures brain
tissue
Brain attack (Stroke) occurs when there is ischemia
to a part of the brain that results in death of brain
cells
Stroke is the syndrome of acute focal neurologic
deficit from a vascular disorder that injures brain
tissue
Risk Factors
Non Modifiable
Age
Sex
Heredity
Non Modifiable
Age
Sex
Heredity
Modifiable Risk Factors
Obesity
HTN
Smoking
Heavy alcohol
consumption
Hypercoagulability
Hyperlipidemia
Diabetes mellitus
Atrial fibrillation
Oral contraceptives
Physical inactivity
Sickle cell disease
Cocaine
Obesity
HTN
Smoking
Heavy alcohol
consumption
Hypercoagulability
Hyperlipidemia
Diabetes mellitus
Atrial fibrillation
Oral contraceptives
Physical inactivity
Sickle cell disease
Cocaine
Types of CVA
Two main types of strokes:
Ischemic
Hemorrhagic
The less common hemorrhagic strokes are caused by
bleeding into brain tissue.
This type of stroke usually is from a blood vessel
rupture caused by hypertension, aneurysms, head
injury, or blood dyscrasias
Two main types of strokes:
Ischemic
Hemorrhagic
The less common hemorrhagic strokes are caused by
bleeding into brain tissue.
This type of stroke usually is from a blood vessel
rupture caused by hypertension, aneurysms, head
injury, or blood dyscrasias
Ischemic stroke
Ischemic strokes are caused by an interruption of
blood flow in a cerebral vessel
most common type of stroke
It account s for 70% to 80% of all strokes
It is Caused by cerebrovascular obstruction by
thrombosis or emboli
Ischemic strokes are caused by an interruption of
blood flow in a cerebral vessel
most common type of stroke
It account s for 70% to 80% of all strokes
It is Caused by cerebrovascular obstruction by
thrombosis or emboli
Types of Ischemic stroke
Ischemic Penumbra in Evolving Stroke
There usually is a central core of dead or
dying cells, surrounded by an ischemic band or
area of minimally perfused cells called the
penumbra
Brain cells of the penumbra receive marginal blood
flow, and their metabolic activities are impaired
Ischemic Penumbra in Evolving Stroke
There usually is a central core of dead or
dying cells, surrounded by an ischemic band or
area of minimally perfused cells called the
penumbra
Brain cells of the penumbra receive marginal blood
flow, and their metabolic activities are impaired
Ischemic Penumbra
Transient Ischemic Attacks
Transient ischemic attacks (TIAs) are characterized byfocal ischemic cerebral neurologic deficits that last forless than 24 hours (usually less than 1 to 2 hours).
TIA is equivalent to “brain angina” It is known as “ministroke” It reflects a temporary disturbance in focal cerebral blood
flow. Causes include Atherosclerotic disease of cerebral vessels Emboli in cerebral vessels
Transient ischemic attacks (TIAs) are characterized byfocal ischemic cerebral neurologic deficits that last forless than 24 hours (usually less than 1 to 2 hours).
TIA is equivalent to “brain angina” It is known as “ministroke” It reflects a temporary disturbance in focal cerebral blood
flow. Causes include Atherosclerotic disease of cerebral vessels Emboli in cerebral vessels
Large Vessel (Thrombotic) Stroke
Thrombi are the most common cause of ischemicstrokes, usually occurring in atherosclerotic bloodvessels.
In the cerebral circulation, atherosclerotic plaques arefound most commonly at arterial bifurcations.
Common sites of plaque formation include largervessels of the brain Internal carotid
Vertebral arteries
Junctions of the basilar and vertebral arteries.
Thrombi are the most common cause of ischemicstrokes, usually occurring in atherosclerotic bloodvessels.
In the cerebral circulation, atherosclerotic plaques arefound most commonly at arterial bifurcations.
Common sites of plaque formation include largervessels of the brain Internal carotid
Vertebral arteries
Junctions of the basilar and vertebral arteries.
Conti…
Cerebral infarction can result from an acute localthrombosis and occlusion at the site of
chronic atherosclerosis
Usually, thrombotic strokes are seen in older persons
It is frequently are accompanied by evidence ofatherosclerotic heart or peripheral arterial disease.
These infarcts often affect the cortex, causingAphasia
Visual field defects
Transient monocular blindness (amaurosis fugax)
Cerebral infarction can result from an acute localthrombosis and occlusion at the site of
chronic atherosclerosis
Usually, thrombotic strokes are seen in older persons
It is frequently are accompanied by evidence ofatherosclerotic heart or peripheral arterial disease.
These infarcts often affect the cortex, causingAphasia
Visual field defects
Transient monocular blindness (amaurosis fugax)
Small Vessel Stroke (Lacunar Infarct)
Lacunar infarcts are small (1.5 to 2 cm) to very small (3 to 4mm) infarcts
located in the deeper, noncortical parts of the brain or in thebrain stem
Affects Basal ganglia, or brain stem Six basic causes of lacunar infarcts have been proposed: Embolism Hypertension Small vessel occlusive disease Hematologic abnormalities Small intracerebral hemorrhages Vasospasm
Lacunar infarcts are small (1.5 to 2 cm) to very small (3 to 4mm) infarcts
located in the deeper, noncortical parts of the brain or in thebrain stem
Affects Basal ganglia, or brain stem Six basic causes of lacunar infarcts have been proposed: Embolism Hypertension Small vessel occlusive disease Hematologic abnormalities Small intracerebral hemorrhages Vasospasm
Cardiogenic Embolic Stroke
It is caused by a moving blood clot that travels from itsorigin to the brain.
It usually affects the larger proximal cerebral vesselsoften lodging at bifurcations.
The most frequent site of embolic strokes is the middlecerebral artery.
Although most cerebral emboli originate from a thrombus in the left heart, they also may
originate in an atherosclerotic plaque in the carotidarteries.
The embolus travels quickly to the brain and becomeslodged in a smaller artery through which it cannot pass.
It is caused by a moving blood clot that travels from itsorigin to the brain.
It usually affects the larger proximal cerebral vesselsoften lodging at bifurcations.
The most frequent site of embolic strokes is the middlecerebral artery.
Although most cerebral emboli originate from a thrombus in the left heart, they also may
originate in an atherosclerotic plaque in the carotidarteries.
The embolus travels quickly to the brain and becomeslodged in a smaller artery through which it cannot pass.
Hemorrhagic Stroke
The most frequently fatal stroke is a spontaneoushemorrhage into the brain substance.
With rupture of a blood vessel, hemorrhage into thebrain tissue occurs
It causes in edema, compression of the braincontents, or spasm of the adjacent blood vessels
The most common predisposing factors areadvancing age and hypertension.
The most frequently fatal stroke is a spontaneoushemorrhage into the brain substance.
With rupture of a blood vessel, hemorrhage into thebrain tissue occurs
It causes in edema, compression of the braincontents, or spasm of the adjacent blood vessels
The most common predisposing factors areadvancing age and hypertension.
Ischemic strokes
Ischemic strokes are subdivided into five different types
according to their cause:
large artery thrombosis (20%)
small penetrating artery thrombosis (25%)
Cardiogenic embolic stroke (20%)
Cryptogenic (30%)
Other (5%)
Ischemic strokes are subdivided into five different types
according to their cause:
large artery thrombosis (20%)
small penetrating artery thrombosis (25%)
Cardiogenic embolic stroke (20%)
Cryptogenic (30%)
Other (5%)
Diagnosis
Accurate diagnosis of acute stroke is based on
a complete history and thorough physical andneurologic examination.
A careful history, including documentation
of previous TIAs, the time of onset and pattern andrapidity of system progression, the specific focalsymptoms
Accurate diagnosis of acute stroke is based on
a complete history and thorough physical andneurologic examination.
A careful history, including documentation
of previous TIAs, the time of onset and pattern andrapidity of system progression, the specific focalsymptoms
Sites of ischemic attacks
Conti…
CT scan for hemorrhage
MRI (Magnetic resonance imaging)
MRA (Magnetic resonance angiography) forvesicular lesion
Positron-emission tomography (PET)
Single-photon emission computed tomography Positron-emission tomography and
Single-photon emission computed tomography
are nuclear studies used to assess the distribution ofblood flow and metabolic activity of the brain
CT scan for hemorrhage
MRI (Magnetic resonance imaging)
MRA (Magnetic resonance angiography) forvesicular lesion
Positron-emission tomography (PET)
Single-photon emission computed tomography Positron-emission tomography and
Single-photon emission computed tomography
are nuclear studies used to assess the distribution ofblood flow and metabolic activity of the brain
Additional studies
Complete blood count
Platelets count
Prothrombin time
Electrolytes, blood glucose
Renal and hepatic studies
Lipid profile
Complete blood count
Platelets count
Prothrombin time
Electrolytes, blood glucose
Renal and hepatic studies
Lipid profile
Treatment
Thrombolytic agents include streptokinase,
recombinant tissue-type plasminogen activator (tPA)
Platelet-inhibiting medications (aspirin)
Thrombolytic agents include streptokinase,
recombinant tissue-type plasminogen activator (tPA)
Platelet-inhibiting medications (aspirin)
References:
Porth, M. C. (2002). Pathophysiology: Concepts ofAltered Health Sciences. (6th ED). USA:
New York. Lippincott Williams &Wilkins