A Bolt From The Blue: Causes, Symptoms and Treatment of Stroke
When people think of a medical emergency, the first thing that pops into their minds is usually a heart attack. The second most well known medical emergency is a stroke. A stroke or cerebrovascular accident is a sudden disruption of blood flow to the brain. The brain is the most oxygen-dependent organ in the body and even a few minutes of oxygen deprivation will result in cell death. This is what happens during a stroke.
A stroke is very similar in action to a heart attack except it occurs in the brain. The area or regions of the brain affected by the disrupted blood supply give rise to different signs and symptoms and cause different types of disability if not treated. A stroke can be fatal and is a leading cause of death worldwide.
There are two types of stroke or cardiovascular attack:
Ischemic, where there is a lack of blood flow.
Hemorrhagic, where there is a rupture of blood vessels and bleeding in the brain.
A majority of strokes are ischemic and hemorrhagic strokes account for only 10% of all cases. It is also possible for an ischemic stroke to evolve into a hemorrhagic stroke. Ischemic stroke is caused by blood clots in the blood vessels of the brain, a blood clot from elsewhere in the body that reaches the brain, or due to abnormal blood vessel structures or distribution.
Hemorrhagic stroke is often caused by burst blood vessels in the brain itself or in the tissue surrounding the brain. Burst blood vessels cause blood to flood into surrounding brain tissue leading to cell damage and cell death.
A stroke is a medical emergency so it is vital to be aware of the warning signs and symptoms of stroke. The major signs of a stroke are aptly summarized by the abbreviation ‘FAST’:
● F- facial weakness, usually on one side. The part of the mouth and the eye on one side of the face may become paralyzed or suddenly start to droop.
● A- arm weakness, either of both or one arm. The person may experience numbness, weakness, or paralysis of the limbs.
● S- speech problems such as slurring and sudden onset of incomprehensible speech is an indicator of a stroke.
● T- time is the most important factor in determining the prognosis of a stroke. Faster treatment can dramatically improve chances of survival and reduce the risk of disability.
Other symptoms of stroke depend on the area of the brain that is affected and includes dizziness, nausea, visual disturbances, confusion, difficulty breathing, and a sudden, severe headache.
A stroke can be caused by a block in blood flow through an artery or due to rupture of blood vessels. These can be caused by the following factors:
A thrombus is a blood clot that forms due to atherosclerosis or plaque formation. Plaque buildup is caused by cholesterol which collects in the blood vessels and narrows them leading to obstruction of normal blood flow.
An embolus is a particle that travels from one part of the body to another. Embolus formation usually originates in the heart. Most emboli consist of clots but can also be made of fat, cancer cells, or bacteria.
Hemorrhage occurs when a blood vessel is weakened which causes it to burst. This can be due to high blood pressure, treatment with anticoagulants (blood thinners), aneurysms (weak spots in blood vessels), arterial malformations, trauma, and drug use (amphetamines and cocaine).
Treatment of stroke depends on the underlying cause of the stroke, whether ischemic, hemorrhagic or a combination of the two. Early detection and treatment is the most important factor in the management of stroke.
Ischemic stroke is usually treated with medications to break up the clot called tissue plasminogen activators or medications to prevent further growth of clots called antiplatelet medications, the most common being aspirin. These medications need to be administered within four hours of symptom onset. Clots or emboli can also be surgically removed.
Hemorrhagic stroke is treated with medications to reduce blood pressure, reduce intracranial pressure, prevent seizures, and reverse the effects of any blood thinners the patient may be taking. Surgery may also be recommended including aneurysm clipping, malformation repair, and endovascular embolization (coiling). Stroke is a severe and often fatal condition. Prevention of stroke is a much better alternative than waiting for the worst to happen- control your blood pressure, diet, and get regular exercise.
