Also known as cerebrovascular accidents, strokes are caused by damage to the arteries which supply oxygenated blood to the brain and are characterised by a sudden loss of neurological function. This loss of neurological function is caused by cerebral infarction (death of the brain tissue). Brain tissue dies when it is deprived of oxygen.
When a stroke damages the motor part of the cerebral cortex often the opposite half of the body becomes paralysed. A stroke in the brain stem results on a coma or death because the vital centres of the body are controlled by this area, such as breathing and blood circulation.
Types of strokes
Cerebral thrombosis: A blood clot forms in one of the carotid arteries and obstructs blood flow to the brain. The clot forms in a section of the artery damaged by artheriosclerosis (hardening of the arteries due to artheromatous plaque). A clot may also form in the carotid arteries, dislodge and travel to the brain where it cuts off blood supply.
Cerebral haemorrhage: This is less common and is caused by bleeding from a diseased artery in the brain. Bleeding normally occurs at the site of arteriosclesoris (hardening of an artery). The diseased artery may weaken and form an aneurysm which ruptures. Blood then escapes into the brain tissue and the pressure destroys the surrounding brain tissue. This type of stroke is accompanied by a sudden and severe headache and sensitivity to light.
Signs and symptoms
These very according to the part of the brain affected and may occur suddenly or gradually, fluctuating in severity.
Symptoms can include a loss of movement (paralysis), weakness, decreased sensation, numbness, loss of co-ordination, vision problems and difficulty in speaking.
Identifying a stroke
- Ask the individual to smile – the mouth will be skew.
- Ask them to speak a simple sentence and check for coherency.
- Ask them to raise both arms – the affected side will be lower.
- Ask them to stick out their tongue – it will be off-centre.
Managing a stroke
Hospitilisation as soon as possible is crucial. The quicker treatment is received the better will be the outcome. A brain scan is done to rule out bleeding and other lesions and to define the location and extent of injury. If there is bleeding or a clot, surgery is performed.
Thereafter treatment is focused on rehabilitation. Speech therapy, physiotherapy, OT and other therapies are used to re-train the brain to take over lost functions.
Risk factors that can’t be changed
- Age: The older a person gets the higher risk there is.
- Sex: Men are more likely to get a stroke but after menopause a woman’s risk rises significantly.
- Family history: If anyone in your family has had a stroke this increases your risk.
- Heart attack: Having a heart attack makes one more prone to a stroke.
- Migraines: If there is a history of migraines then the risk is higher.
- Sickle cell anemia: People with this condition are at risk from a young age.
- A prior stroke makes you more at risk.
- Berry aneurysms: These are small sac-like areas within the wall of an artery with which some people are born. These rupture without cause and cause haemorrhaging.
Risk factors that can be controlled
- High blood pressure and cholesterol
- Heart diseases that can be treated with medication.
- Diabetes type 2
- Blood clotting disorders.
- Sleep apnoea. People with this condition are 3 times more at risk for a stroke. It is treated by weight management and devices can be used (CPAP machine).
- Alcohol consumption.
- Smoking combined with birth control pills is a recipe for a stroke.
- Lack of exercise
Supplements to help prevent strokes:
Alpha lipoic acid, folic acid, calcium, B6, B12, magnesium, Omega 3,6,9, potassium, Vitamin C and E.
Camelot international pathophysiology manual (2013)