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Stroke - Fact Sheet
 A stroke is an
interruption of blood supply to part of the brain. Nutrients and oxygen are
passed to each cell through the arteries. If these become blocked, bleed or
break then the brain tissue that was being nourished deteriorates.
When this lack of blood supply occurs to
the heart it is called a heart attack. When it occurs in the brain it is called
a stroke. In fact, in America
a stroke is called a “brain attack”.
According to the Australian Institute of
Health and Welfare report Heart, stroke
and vascular diseases, Australian facts 2004, stroke is Australia’s second
biggest killer after heart attack, and 90% of Australian adults have at least
one modifiable (i.e. can be improved) risk factor. Although stroke is rarely
immediately fatal, the Stroke Association of Queensland report that just over a
third of people who have a stroke will die within the first 12 months, and just
under a third will require long-term care.
Types of stroke
Obstruction of a blood
vessel:
A  Blood Clot can cause a blockage in an
artery. These clots can occur in other parts of the body then break up and
travel to the brain where they lodge in the smaller blood vessels. A blood clot that forms in a blood vessel or within the heart and
remains there is called a Thrombus. A thrombus that travels to another
location in the body is called an Embolus. The disorder is called an
Embolism. For example, an embolus that occurs in the brain is called a
Cerebral embolism.
Fatty lipids called plaques may build up on
the walls of blood vessels and restrict blood flow. As a result symptoms
usually develop slowly but may be rapid in some cases.
Aneurysm:
An aneurysm is a localised swelling of a
blood vessel. This can be caused by disease, congenital weakness of the blood
vessel, or injury. If an aneurysm does not burst it can become blocked, leading
to a stroke through obstruction. If it does not block, it does not usually
produce any symptoms and may not be detected. If an aneurysm bursts, however,
the result is a haemorrhage.
Haemorrhage:
A haemorrhage is loss of blood from a blood
vessel. In other words, bleeding. There are two kinds of haemorrhage that can
cause a stroke. An intracerebral haemorrhage is caused by a ruptured artery
leaking blood directly into the brain. A subarachnoid haemorrhage occurs on the
surface of the brain and the blood fills the space around the brain and creates
pressure.
As well as starving regions of the brain of
blood, the increased pressure created by blood pooling inside or outside the
brain can impact the function of neurons and lead to them slowly dying.
Effects of stroke
The after effects of a stroke vary widely
for each stroke victim as different parts of the brain are responsible for
thought processes, comprehension, movement and our senses. The extent of blood
shortage also determines the effect of the stroke.
Left Hemisphere:
A stroke in the left hemisphere of the
brain may result in:
- Some degree of paralysis on the
body’s right side
- Loss of feeling on body’s right
side
- Right field of vision
deterioration
- Loss of speech or comprehension
(Aphasia), and other speech problems including Echolalia (exact repetition of a
word or sentence just spoken by another person), Perseveration (continual
repetition of a word or phrase), inappropriate use of "yes" and
"no" and inability to discriminate between left and right.
- Inability to name objects that
can be recognised and used.
- Inappropriate laughing or
crying.
- Easily becoming frustrated.
Right Hemisphere:
A stroke in the right hemisphere of the
brain may result in:
- Some paralysis on the body’s
left side
-
Lost or disturbed (hot or cold,
acute or diminished pain) feeling on body’s left side
- Left field of vision
deterioration - may only eat from right hand side of plate.
- Poor judgement, Impulsivity or
a lack of awareness of personal limitations.
- Short attention span or
difficulty following instructions.
- Difficulty expressing emotions,
or inappropriate emotions.
- Inability to read facial
expressions or voice tone in other people.
- Difficulty speaking, slurred
speech or incessant and repetitive talking.
- Difficulty with simple
addition, subtraction, multiplication, division or a simple thought problem.
- Difficulty using money, dialling
a telephone or recognizing the time on a clock.
- Spatiotemporal difficulty with
a tendency to get lost if left alone or if out of one’s environment.
Although the left and right hemispheres of
the brain are usually affected, damage in the lower levels of the brain can
also occur. The brain stem and cerebellum are involved in maintaining vital
body systems, reflexes and balance. A stroke in the brain stem can cause:
- Unconsciousness
-
Inability to speak
- Paralysis
-
Unstable pulse
-
Blood pressure fluctuations
- Difficulty swallowing or
breathing
- Difficulty with eyeball
movement.
A stroke in the cerebellum can cause:
- Double vision
- Dizziness and loss of balance
- Lack of coordination in the
hands
- Slurred speech.
How to recognise a stroke
A stroke is not necessarily a major event,
and may not be recognisable as a stroke - it may only result in someone
stumbling or having a moment of blankness akin to an absent Seizure. However,
it is vital to treat a stroke quickly, if possible within 3 hours.
STR
The first three letters of “Stroke”, STR,
provide a mnemonic for diagnosis. If you suspect that someone may have suffered
a stroke or even a seizure, ask them to do the following:
- S is for “Smile”
- T is for “Talk”
- R is for “Raise both arms”
If they have problems with any of these
activities, or if they are unable to coordinate their limbs normally, ring an
ambulance immediately. You may save their life.
FAST
The other mnemonic you can use is to act
“FAST”:
- Facial numbness or weakness.
- Arm numbness or weakness
- Slurred speech
- Time to call an ambulance!
Treatment
Surgery, drugs, acute hospital care and
rehabilitation are all accepted stroke treatments depending on the type of
stroke.
An example of surgery is a carotid
endarterectomy to remove plaque if a neck artery is blocked. Aspirin is a
common drug used for thinning the blood. Other medications aim to dissolve
clots that lead to stroke. New techniques continue to arise, such as cerebral
angioplasty where balloons, stents and coils are used to dilate small
intracranial arteries and maintain blood flow.
Recovery
Generally speaking the brain does not
regenerate if brain tissue dies after an embolism or thrombosis. After a
haemorrhage the brain may regain some function after the pressure caused by
bleeding has decreased.
Recovery after a stroke depends on a number
of factors including:
- The type and severity of the
stroke
- The part of the brain involved
- The extent and nature of the
damage
- Existing medical problems
-
Type of treatment and
rehabilitation.
Recovery usually involves a lot of
relearning of activities such as walking and talking. This learning can be
complicated by the fact that many people have trouble concentrating after a
stroke. Research funded by the Stroke Association of Queensland found that
attention was affected markedly by a stroke in the front right side of the
brain. This part of the brain is responsible for attention and concentration
and a stroke here was found to lead to slower rehabilitation as learning was
impaired.
Rehabilitation
Rehabilitation aims to:
- Help you understand and adapt
to your difficulties
- Regain skills
- Prevent secondary complications
- Help you and your family to
come to terms with the stroke.
The team involved can be quite confusing
for some patients. A physiotherapist may be involved in assessing and assisting
with muscle strength, balance and mobility. An occupational therapist helps
with relearning practical tasks of everyday life such as dressing, washing and
using cutlery. A speech language pathologist works not only with communication
difficulties but also with problems of swallowing. A social worker may assist
with counselling and advice about community support, financial issues and other
services. A Neuropsychologist may assist with Cognitive changes and problems
controlling emotions. The rehabilitation doctor’s role is to integrate medical
requirements and treatments with the other therapies.
Knowledge of rehabilitation following a
stroke is growing steadily, as neurologists and neuropsychologists experiment
with using mirrors or offset treadmills to retrain muscle groups and nerve
pathways. As with any other form of brain injury, the key is understanding,
persistence and a close relationship with the medical team.
How can the family help?
The family can play a huge part in the
rehabilitation process. Ideally they should be included in some team meetings
and sessions so that they can carry on the learning process of their loved one.
Families can provide the emotional support that is crucial to recovery and also
keep the person in touch with the outside world. Families also need to look
after themselves and may benefit from attending a support group for carers. A
support group can also be invaluable for their loved one.
Emotions following a
stroke
A person who has had a stroke can
experience a wide range of emotions which are ‘normal’ reactions to an abnormal
experience, including, shock, anger, denial, depression, frustration, guilt and
grief. The shock of the stroke can combine with the effects of the stroke upon
the brain to cause unstable, or labile, emotions that are socially
inappropriate and which may harm the chances of rehabilitation.
It is important to share these feelings and
ask for help. Reassurance that these feelings are to be expected can be a great
relief.
For more information, see the BIAQ Fact
Sheet "Emotional Stages in Recovery".
Further information
For further assistance contact the Stroke
Association or Brain Injury Association in your State.
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Stroke 
