Stroke
Introduction
The brain requires a continuous supply of oxygen and nutrients from the blood in order to function properly. A blockage, interruption or severe reduction in the supply of blood to the brain can result in a condition called a stroke. Stroke is a medical emergency that leads to the death of brain cells within minutes of the interruption in blood supply. Prompt treatment is vital to minimize brain damage and improve outcomes.
Stroke is more common in men over 55 and African Americans.
Type
Strokes may be classified as ischemic, haemorrhagic or transient ischemic.
Ischemic stroke is the most common type of stroke and is caused by narrowing or blockage of the brain’s blood supply due to a blood clot. The clot can develop in an artery of the brain (thrombotic stroke) or in another part of the body and travel up to the brain (embolic stroke).
Haemorrhagic stroke:
A haemorrhagic stroke occurs when a blood vessel leaks or ruptures as a result of trauma, uncontrolled hypertension, blood thinning medication, weakened area of a blood vessel (aneurysm) and diseases that affect the blood vessels.
Transient ischemic attack (TIA): This type of stroke, also referred to as a mini stoke, occurs from a temporary reduction in blood supply to parts of the brain, often lasting less than 5 minutes.
Risks
There are many factors that can increase your risk of developing a stroke including lack of exercise, binge drinking, smoking, second hand smoke, illicit drugs, being overweight and medical conditions such as high blood pressure and cholesterol, diabetes, sleep apnoea and heart conditions.
Signs and Symptoms
A stroke causes brain damage that can result in various symptoms depending on the area of the brain affected.
Symptoms include
- Sudden headache
- Difficulty with balance and coordination
- Paralysis on one side of the body
- Problems with communication
- Cognitive difficulties
- Vision abnormalities
Sometimes the damage is progressive and can lead to death.
In patients who experience a TIA, the symptoms are short-lived and usually resolve on their own. It is important to understand however that your risk of a full-blown stroke in the future is increased following a TIA.
Diagnosis
When you experience the onset of stroke symptoms, immediate initiation of care is imperative to minimize further brain damage and prevent death. Initial diagnosis of the type of stroke and your functional deficits is performed by the emergency team. A doctor reviews your symptoms and medical history and performs a physical examination. Your blood pressure is measured and the arteries in your neck and eyes are examined. Blood tests, imaging tests such as a CT, MRI, cerebral angiogram, echocardiogram and carotid ultrasound, are usually ordered to examine the structure of the arteries and flow of blood, and to identify the areas of brain damage and blocked arteries.
Treatment
Stoke is a medical emergency and the emergency response system should be initiated at the onset of symptoms. Early medical intervention increases your chance of survival and may minimize adverse outcomes.
The management of stroke is prioritized as follows:
- Stabilizing your condition
- Controlling life-threatening symptoms
- Preventing recurrence and associated complications
- Rehabilitation
Treatment depends on what type of stroke has occurred. For ischemic strokes, clot busting medication called TPA is usually given intravenously within 3 hours of the stroke. TPA restores blood flow to the brain by dissolving the blood clot.
For haemorrhagic stroke, medication to counteract any blood thinners you take is given and blood pressure-lowering medications may be administered.
Surgery may be necessary to remove blood clots and repair ruptured blood vessels. Your surgeon may clamp or insert coils to cut off blood supply to aneurysms, or use a graft to bypass regions of poor blood flow.
Recovery from a stroke requires long-term support. Rehabilitation can begin as early as 24 to 48 hours after your stroke once your condition is stable. Rehabilitation is aimed at relearning lost skills and improving your quality of life.
You may need to make a few lifestyle changes such as maintaining a healthy diet and weight with regular exercise, limiting alcohol intake and refraining from smoking.
