Stroke
Content
Stroke
• Etiology
• Pathophysiology
• Types of stroke
• Treatment
OBJECTIVES
At the end of this PDF Notes, the students will
be able to:
• Define stroke
• Classify stroke
• Explain the etiology of stroke
• Discuss the pathophysiology of
stroke
Stroke
What is STROKE?
• Sudden brain damage
• A stroke occurs when a blood clot blocks a
blood vessel or artery, or when a blood vessel breaks, interrupting blood flow
to an area of the brain
• Lack of blood flow to the brain caused by
a clot or rupture of a blood vessel
Strokes occur in the
brain and affect the opposite side of the body
National Stroke
Association encourages everyone to spread awareness about stroke in May about
how to:
- STOP primary and
secondary stroke through risk factor management
- Act F.A.S.T. to
increase recognition of and response to stroke symptoms
- Spread HOPE about
recovery from stroke
May is National Stroke
Awareness Month
STROKE FACTS
• A leading cause of death in the United States
• 795,000 Americans suffer strokes each year
• 134,000 deaths each year
• From 1996 to 2006, the stroke death rate fell
33.5% and number of deaths fell by 18.4%
• A leading cause of adult disability
•
Types of Strok
Hemorrhagic Stroke
Ischemic Stroke
HEMORRHAGIC STROKE
•
• Approximately 20% of the strokes are
hemorrhagic in nature
• Most leading cause is high blood pressure
occurring when a blood vessel bursts and blood accumulates
• Subarachnoid hemorrhage and
• Intracerebral hemorrhage
ETIOLOGY:
• Traumatic head injury
• Burst of cerebral aneurysm
• A defect of the circulatory system/a cluster of
abnormally formed blood vessels (also called arteriovenous malformation or
AVMs, usually inherited at birth)
1. Subarachnoid Hemorrhage
• Subarachnoid hemorrhage - most severe form of a
stroke - permanent disability or death
• It can happen suddenly when a major blood vessel
bursts upon the surface of the brain causing spilling blood into the
cerebrospinal fluid surrounding the brain
• Due to bleeding, the amount of fluid increases
in the affected area - enormous pressure on the whole brain - damage to the
brain tissue
• Aneurysm is a ballooning of a weakened area of
an artery and when left untreated the aneurysm can continuously become weakened
until it ruptures and finally bleeds into the brain
• Burst aneurysm can lead to a sudden and severe
headache, usually with a description of “thunderclap”
• CT scan or an MRI - detect the presence of
subarachnoid hemorrhage
Intracerebral hemorrhage
• Intracerebral hemorrhage happens when there is
a burst of a blood vessel in the brain - leaking of blood into the brain
• It is more common among people aged above 60
and can be most commonly caused by high blood pressure
• It can
also be a result of infections, a burst aneurysm tumors or head injuries
ISCHEMIC STROKE
• Ischemic stroke is a sudden loss of brain
function and can be caused by partial or complete obstruction of a blood vessel
supplying the brain
• Approximately 80% of strokes are ischemic in
nature, and it occurs when there is a blockage inside the carotid arteries or
in the vertebral arteries
• A fatty deposit (a plaque) or mass of blood
cells (a clot) travelling in the blood can get trapped in a narrowed or small
artery - obstruct blood flow - occurrence of a stroke
There are three types
of Ischemic stroke:
- Lacunar stroke
- Thrombotic stroke
- Embolic stroke
1. Lacunar stroke:
• Lacunar stoke contributes to 25% of ischemic
strokes and occurs when there is a blockage in one of the smaller blood vessels
found inside the brain
• A “hole” of scar tissue is due to the blockage
that starves a small part of the brain
• As only small portion of the brain is affected,
lacunar stroke is usually hard to be diagnosed
2. Thrombotic stroke:
• It happens when the artery is clogged by plaque
and hardens, or when a cholesterol-filled plaque of atherosclerosis especially
in a brain (cerebral), carotid or vertebral artery breaks open - formation of a
blood clot over the plaque obstructing blood flow
• Thrombus (blood clot) is a condition where the blockage seals off the blood vessel
3. Embolic Stroke:
• An embolus refers to a piece that breaks
off and can block a blood vessel
supplying the brain causing the occurrence of an embolic stroke which
contributes 60% of ischemic strokes
• Unless the source is found and treated
immediately, people with embolic strokes are at potential risk of another
stroke/s
• Embolic strokes hit fast and sudden and are
normally severe
RISK FACTORS OF STROKE
- High blood pressure is the number one risk
factor for strokes.
- Atrial fibrillation
- Diabetes mellitus
- Family history of stroke
- High cholesterol
- Increasing age, especially after age 55
- Race (black people are more likely to die
of a stroke)
- People who have heart disease or poor
blood flow in their legs caused by narrowed arteries
- Being overweight or obese
- Drinking heavily
- Eating too much fat or salt
- Smoking
- Taking cocaine and other illegal drugs
- Birth control pills can increase the
chances of having blood clots. The risk is highest in woman who smoke and
are older than 35
Signs & Symptoms
Sudden and severe
headache
Trouble seeing in one or both eyes
Sudden dizziness
Trouble walking
Sudden confusion
Trouble speaking
Sudden numbness
or weakness of face, arm or leg
RECOGNIZE THE SYMPTOMS OF A STROKE
• 3 Simple Questions
– Ask the person to smile
– Ask the person to raise both arms
– Ask the person to say a simple sentence “The
sky is blue ”
Diagnosis
• Diagnostic Testing
• CT or MRI of the brain
• EKG
• Carotid Ultrasound
• Echocardiogram
Summary
• stroke occurs when a blood clot blocks a blood
vessel or artery, or when a blood vessel breaks, interrupting blood flow to an
area of the brain
• Hemorrhagic stroke occurs as a result of
traumatic head injury, burst of cerebral aneurysm a defect of the circulatory
system/a cluster of abnormally formed blood vessels
• Ischemic stroke occurs due to sudden loss of
brain function and can be caused by partial or complete obstruction of a blood
vessel supplying the brain by atherosclerotic plaque
Posts
0 Comments