Synapse - reconnecting lives

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 Foundation report that One in five people having a first-ever stroke die within one month and one in three die within a year. Australians will suffer around 60,000 new and recurrent strokes (that's one stroke every 10 minutes).

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

Brain Stem and Cerebellum

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. It is vital to treat a stroke immediately call an ambulance.

FAST

The FAST test is an easy way to recognise and remember the signs of stroke. Using the FAST test involves asking three simple questions:

• Face - Check their face. Has their mouth drooped?
• Arms - Can they lift both arms?
• Speech - Is their speech slurred? Do they understand you?
• Time - Time is critical. If you see any of these signs call an ambulance straight away.

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 Fact Sheet Emotional Stages in Recovery.