Stroke

1. Stroke
Presented By Miss Sudipta Roy
Designation : Associate Professor
East Point College Of Pharmacy , Bangalore

2. • A stroke happens when blood flow to a part of the
brain stops and it is sometimes called a ''brain
attack''.
• Definition :
• A stroke occurs when the blood supply to part of
your brain is interrupted or severly reduced ,
depriving brain tissue of oxygen and nutrients.
Within minutes , brain cells begin to die.
• or
• A stroke is a rapid loss of brain function due to the
disturbance in the blood supply to brain.

3. • Area of temporarily blocked blood flow.
• Blood dot in the middle cerebral artery.
• Blokage in the internal carotid artery.
• Types of stroke.
• stroke is classified as follows :
• Stroke :
• Ischemic stroke
• Hemorrhagic stroke
• Transient Ischemic Attack (TIAs)

4. Ischemic Stroke.
• Ischemic Stroke is the most common form of stroke, about 80
percent of strokes are ischemic strokes.This type of stroke is
caused by blockages or narrowing of the arteries that provide
blood to the brain , resulting in ischemia : Severly reduced blood
flow. These blockages are often caused by blood clots. Clots can
be caused by fatty deposits within the arteries called plaque.
• Ischemic Stroke.
• Blood clot lodges in cerebral artery causing a stroke.
• Blood clot breaks off and travels
• Diseased carotid artery
• Normal carotid artery
• The most common ischemic strokes include :
• Thrombotic Stroke
• Embolic Stroke

5. • Thrombotic stroke.
• A thrombotic stroke occurs when a blood clot (thrombus) forms in one of the
arteries that supply blood to your brain. A clot may be caused by fatty deposits
(plaque) that build up in arteries and cause reduced blood flow (atherosclerosis)
or other artery conditions.
• Embolic Stroke.
• An embolic stroke occurs when a blood clot or other debris forms away fro your
brain commonly in your heart and is swept through your blood stream to lodge
in narrower brain arteries. This type of blood clot is called an embolus.
• 2. Hemorrhagic stroke :
• Hemorrhagic stroke occurs when a blood vessel in your brain leaks or ruptures.
Brain hemorrhages can result from many conditions that affect your blood
vessels . These include.
• Uncontrolled high blood pressure (hypertension)
• Overtreatment with anticoagulants (blood thinning medications)
• Trauma
• Aneurysms (weakness in blood vessel walls).

6. Difference between Ischemic
stroke and Hemorrhagic stroke.
• Ischemic stroke.
• Anoxia
• Thrombus
• Hemorrhagic stroke :
• Hemorrhage
• A rupture of the vessel
• The most common hemorrhagic strokes include :
• Intracerebral Hemorrhage
• Subarachnoid Hemorrhage

7. Intracerebral Hemorrhage.
• Intra cerebral hemorrhage is the most common
type of hemorrhagic stroke and occurs when brain
tissue is flooded with blood after an artery in the
brain bursts.
• In an intracerebral hemorrhage , a blood vessel in
the brain bursts and spills into the surrounding
brain tissue , damaging brain cells . Brain cells
beyond the leak are deprived of blood and are also
damaged.
• Causes : High blood pressure , trauma , vuscular
malformations, use of blood thinning medications
and other conditions may cause an intraerebral

8. Subarachnoid Hemorrhage.
• Subarachnoid hemorrhage is the second type of
hemorrhagic stroke and is less common. In this type of
stroke , bleeding occurs in the subarachnoid space : the
area between the brain and the thin tissues that cover it .
In a subarachnoid hemorrhage, an artery on or near the
surface of your brain bursts and spills into the space
between the surface of your brain and your skill. This
bleeding is often signaled by a sudden, severe headache.
• Causes : A subarachnoid hemorrhage is commonly caused
by the bursting of a small sack-shaped or berry shaped
aneurysm. after the hemorrhage ,the blood vessels in
your brain may widen and narrow erratically (vasospasm)
, causing brain cell damage by further limiting blood flow.

9. Transient Ischemic Attack (TIAs) .
• TIAs are different from the both kinds of stroke
because the flow of blood to the brain is only
briefly interrupted. A transient ischemic attack (TIA)
sometimes known as a ministroke.It is a temporary
period of symptoms similar to ischemic strokes in
that they are often caused by blood clots or other
debris. A temporary derease in blood supply to part
of your bain causes TIAs that may lasts as little as
five minutes. Like an ischemic stroke, a TIA occurs
when a clot or debris blocks blood flow to the brain
(trsnsient ischemic or TIA) that does not cause
permanent damage and no lasting symptoms.

10. Etiology.
• Stroke can be caused due to -
• 1. A stroke may be caused by blocked artery (ischemic stroke).
• 2. The leaking or bursting of a blood vessel (hemorrhagic stroke).
• 3. Some people may experience only a temporary disruption of
blood flow to the brain (transient ischemic attack , or TIA) that does
not cause permanent damage.
• The different types of strokes have different causes . However ,
stroke is more likely to affect people if they have the following risk
factors.
• Being overweight.
• Being Aged 55 years or older.
• A personal or family history of stroke.
• An inactive lifestyle
• A tendency to drink heavily, smoke or use ilicit drugs.

11. Pathophysiology.
• Brain uses about one quarter of the body's energy
supply . Brain uses glucose as its sole substrate for
energy metabolism. Glucose metabolism leads to
conversion of adenosine diphosphate (ADP) into
adenosine triphosphate (ATP). A constant supply of ATP
is needed to maintain neuronal integrity and to keep
the major extracellular Ca++ and Na+ outside the cells
and the intracellular K+ within the cells. Production of
ATP is much more efficient in the presence of oxygen.
Although in the abscence of oxygen , brain cell
undergoes anaerobic the presence of oxygen . Although
in the abscence of oxygen , brain cell undergoes
anaerobic energy generation to get more energy and
anaerobic metabolism produce less adenosine
triphosphate but released by product called lactic acid.

12. • Lactic Acid is an irritant which could potentially
destroy cells since it is an acid and disrupts the
normal acid base balance in the brain. Ischemic
Stroke occurs due to decrease in blood supply to
part of the brain , initiating the ischemic cascade.
Brain tissues get injured after 60-90 seconds of
ischemia or less oxygen supply. Within 3 hours of
ischemia brain tissues injured irreversibly leads to
death of tissue . Atherosclerosis reduces the
diameter of blood vessels by forming plaque which
reduces blood supply to the brain.

13. • Reduced Cerebral Blood Flow
• ATP Depletion - Neurochemical Injury (Lactic
acidosis (ATP depletion) , Edema (Electrochemical
gradient loss) , Oxidative stress (Mitochondrial
damage) and Neuroinflamatory Injury : Reactive
astrocytes , Activated microglia , Neutrophil
infiltration are both reversible.
• Cell damage and Neuronal Death.
•

14. Clinical Manifestations.
• Trouble with speaking and uderstanding :
• Patient may experience confusion. There may be a slurring of
speech or he may feel difficulty in understanding speech.
• Paralysis or numbness of the face , arm or leg :
• Patient may develop sudden numbness, weakness or paralysis in
facial muscles , arm or leg . This happens just on one side of
patient body.
• Visual Effects : Patient may suddenly have blurred or blackened
vision in one or both eyes.
• Headache : A sudden , severe headache , which may be
accompanied by vomiting , dizziness or altered consciousness
may indicate that person is having a stroke.
• Trouble with walking : Patient may stumble or experience sudden
dizziness, loss of balance or loss of coordination.

15. Complications.
• Cerebral Swelling.(Edema)
• Increased intracranial pressure (ICP)
• Intracerebral hemorrhage
• Seizures
• Paralysis on one side of the body (hemiparesis) and
speech problems may occur.

16. Diagnosis.
• MRI Scan
• CT scan
• Cerebral Angiogram : To get a detailed look at the
arteries in the neck and arm.
• Carotid ultrasound : A carotid ultrasound also
called duplex scan , can show fatty deposits
(plaque) in your carotid arteries, which supply the
blood to your face, neck and brain.
• Echocardiogram : It can find the source of clots in
the heart. These clots may travel to brain and can
cause a stroke.

17. Treatment.
• Lifestyle changes can't prevent all strokes. But
many of these changes can make a radical
difference when it comes to lowering your risk of
stroke.
• These changes include the following :
• 1. Quit Smoking
• Limit Alcohol Use
• Keep a moderate weight
• Get regular checkups

18. Pharmacological Treatment.
• Treatment for stroke depends on the type of stroke.
• Ischemic stroke and TIA : Since a blood clot or blockage in the brain causes
these stroke types, they are largely treated with similar techniques. They
can conclude :
• 1. Clot breaking drugs : Thrombolytic drugs can break up blood clots in
brain's arteries which will stop the stroke and reduce damage to the brain.
• Examples : Tissue Plasminogen Activator (tPA) or Alteplase IV
• 2. Mechanical Thrombectomy : During this procedure , a doctor inserts a
catheter into a large blood vessel inside your head. They then use a device
to pull the clot out of the vessel . This surgery is most successful if it's
performed 6 to 24 hours after the stroke begins.
• Stents : If a doctor finds where artery walls have weakened , they may
perform a procedure to inflate the narrowed artery and support the walls of
the artery with a stent.
• Surgery : In the rare instances that other treatments don't work , surgery
can remove a blood and plaques from the arteries.

19. Hemorrhagic Stroke.
• Strokes caused by bleeds or leaks in the brain require different treatment
strategies . Treatments for hemorrhagic stroke include.
• 1. Medications :
• Medicines are given to make a blood clot . Patient may also be prescribed drugs
that can :
• Reduced blood pressure.
• Lower the pressure in your brain.
• Prevent seizures.
• Prevent blood vessel constriction.
• 2. Coiling : During this procedure, doctor guides a long tube to the area of
hemorrhage or weakened blood vessel . They then install a coil like device in the
area where the artery wall is weak. This blocks blood flow to the area reducing
bleeding.
• 3. Clamping : During imaging tests, doctor may discover an aneurysm that has
not started bleeding yet or has stopped. To prevent additional beeding, a
surgeon may place a tiny clamp at the base of the aneurysm. This cuts off blood
supply and prevents a possible broken blood vessel or new bleeding.