What is a stroke?
A stroke is characterised by the rapid appearance (usually over minutes) of reduced or lost function of a part of the brain.
85% of strokes is due to brain death following inadequate blood flow to part of the brain (ischaemic stroke), and the remainder is due to bleeding into the brain (haemorrhagic stroke). The latter is usually characterised by the combination of severe headache and vomiting at the onset of the focal neurological deficits.
The commonest cause of interrupted blood flow is a blood clot getting stuck in the blood vessels supplying the brain. Factors that can increase the likelihood of developing ischaemic stroke include increasing age, male gender, black race, family history of stroke, previous stroke or heart attack, high blood pressure, heart disease, diabetes mellitus, smoking, excess alcohol consumption, oral contraceptives and social deprivation.
Bleeding into the brain usually results from rupture of a blood vessel within the brain tissue. The risk factors and underlying causes of intracerebral haemorrhage include increased age, high blood pressure, family history of stroke, blood thinning drugs, misuse of alcohol and other substances.
What are the symptoms?
The symptoms of stroke depend on which area is involved and the size of the damage, both of which will have a bearing on management. They include:
- An impairment of movement on one side of the body
- Speech and swallowing difficulties
- Visual impairment
- Postural and walking difficulties
- Double vision
- Vertigo or dizziness
- Muscle weakness on both sides
- Reduced conscious level
A stroke is an emergency. It’s very important to get medical attention straight away. Treatment is preferable in hospitals with specialist stroke units.
What treatments work?
Management is aimed at minimising the volume of brain that is irreversibly damaged, preventing complications, reducing disability and handicap through rehabilitation, and reducing the risk of another stroke.
Early admission to a specialised stroke unit facilitates coordinated care from a specialised team and has been shown to reduce both mortality and residual disability amongst survivors. If there is difficulty swallowing, you may need a tube passed into your stomach or a drip for feeding and taking medications. In some cases, symptoms may worsen during the first few hours or days after their onset even with adequate medical care. If there is so much fluid in the brain, you may be given some drugs or have surgery done to bring it down.
Treatments for a stroke caused by a blood clot
Most strokes are caused by a blood clot that blocks a blood vessel. So you’ll probably be given drugs that break down the clot e.g. alteplase, or drugs to stop clots from forming e.g aspirin. This type of treatment is called thrombolysis. Both can cause unwanted bleeding, including a brain haemorrhage. A surgery can also be done to remove the clots in the brain.
Treatment for a stroke caused by bleeding
Strokes caused by bleeding into the brain, rather than by blood clots, often need surgery. This is to repair the broken blood vessel and remove the extra blood that’s pooled in the brain. Surgery is more likely to be needed when the bleeding is severe.
What will happen?
More than half of people go on to make a good recovery and are able to take care of themselves. About one third of people will not recover completely (for example, enough to work) and about 1 in 10 people who have a stroke will die from it. The outlook is better for younger people, men, and people who don’t have other health problems.
Having a stroke puts you at risk of having another one. So doctors often recommend treatment to lower the risk.