Stroke (also known as cerebrovascular disease) occurs when the supply of blood to the brain is suddenly disrupted. Blood is carried to the brain by blood vessels called arteries. Blood may stopmoving through an artery because the artery is blocked by a blood clot or plaque, or because the artery breaks or bursts.
A stroke can occur in two main ways:
1. Ischaemic stroke (blocked artery) OR
2. Haemorrhagic stroke (bleed in the brain)
When blood is stopped, the brain cannot get the oxygen it needs, brain cells in the area die and the brain can become permanently damaged. Brain cells usually die within an hour from the beginning of the stroke but can survive, at times, up to a few hours after the stroke starts. Areas of brain where the blood supply is reduced but not completely cut off are areas that can survive for some hours. These cells are in a state of shock and can either recover or die depending on what happens in the minutes and hours that follow. Without prompt medical treatment, this area of brain cells will also die because they are no longer receiving the oxygen and nutrients they need to function. These cells usually die within minutes to a few hours after the stroke starts.
Stroke needs to be investigated promptly to find the type and cause of the stroke to try to prevent a recurrence (secondary prevention), usually with medication and occasionally blood vessel surgery.
Effects of a Stroke
The brain controls the way we move, think, speak, and eat. Everything we do is controlled by different parts of the brain. When a stroke happens, we lose the ability to do things that, that part of the brain controls. We may not be able to move one side of the body or have trouble thinking or speaking. The way in which people are affected by stroke depends on where in the brain the stroke occurs, and on the size of the stroke. For example, someone who has a small stroke may experience only minor effects. On the other hand, someone who has a larger stroke may be left totally paralysed on one side, in a coma or may die due to the extent of the damage. Stroke is always a medical emergency. It is important to recognise the early signs of a stroke or TIA.
If you experience any signs of stroke call 000 even if the symptoms last for only a short time.
A FAST test for stroke
The FAST test is an easy way to recognise and remember the most common signs of a stroke. The FAST test stands for:
- Face – Check their face. Has their mouth drooped?
- Arms – Can they lift both arms?
- Speech – Is their speech slurred? Do they understand you?
- Time – Is critical.
If you see any of these signs call 000 straight away. All the signs of both stroke and TIA may be any one, or combination of the following:
- Weakness or numbness or paralysis of the face, arm or leg on either or both sides of the body
- Difficulty speaking or understanding
- Dizziness, loss of balance or an unexplained fall
- Loss of vision, sudden blurred or decreased vision in one or both eyes
- Headache, usually severe and of abrupt onset or unexplained change in the pattern of headaches
- Difficulty swallowing