Stroke is the loss of brain function due to irregular supply of blood to the brain. The brain, as the control centre of the body, is constantly fed by blood vessels with oxygen and needed nutrients to keep it operating smoothly. In times when a certain health problem causes heart failure or blood vessel damage, the brain is unable to get the necessary substances it needs. Stroke is any condition by which blood vessels are blocked and the supply of blood to the brain is obstructed. Another name by which stroke is called is cerebrovascular disease (CVA).

Stroke is a clinical emergency; causing permanent neurological damage and death, if not promptly diagnosed and treated. It is one of the most prominent causes of death and adult disability in the United States and Europe. As presented by the National Institutes of Health, there is a person in the United States that has a stroke every 45 seconds. It is estimated that stroke will soon become the most prominent cause of death worldwide.

Classification

There are generally two types of stroke: ischemic stroke and hemorrhagic stroke. Ischemia is due to decrease of the blood supply, while hemorrhage is due to puncture of a blood vessel. Ischemic stroke can occur when a blood vessels is blocked, possibly by a blood clot or by cholesterol deposits, and hence is unable to deliver blood to and from the brain. Hemorrhagic stroke occurs when an artery or a vein bursts or leaks into the brain, causing blood to flood it. This can possibly lead to nerve damage and permanent brain damage. Nearly 75% of strokes are due to ischemia while the rest are due to hemorrhage.

Ischemic stroke
In an ischemic stroke, blood supply to part of the brain is decreased, leading to malfunction of the brain tissue in that area. This may be due to thrombosis (obstruction of a blood vessel by a blood clot), embolism ( due to a blood clot from elsewhere in the body), systemic hypoperfusion (general decrease in blood supply, e.g. in shock) and venous thrombosis.

Hemorrhagic stroke
Intracranial hemorrhage is the flooding of blood within the skull .This hemorrhagic stroke is caused by headache, or head injury. Intracerebral hemorrhage is bleeding directly into the brain tissue. It generally occurs in small arteries and is due to hypertension, trauma, bleeding disorders, illicit drug use (e.g. amphetamines or cocaine), and vascular malformations.

What makes a person likely to experience a stroke? This can usually occur following a serious head injury, which may be the cause of bleeding. Persons with a history of cardiovascular diseases such as hypertension and heart failure may also be likely candidates for stroke. Studies have shown that men have strokes more often than women, but pregnant women are also likely to have it. Using dangerous drugs like cocaine, and heavy cigarette smoking make a person more prone to stroke, along with other serious diseases. In summary, people with the following are considered the high risk groups for stroke: Advanced age, hypertension , previous stroke , diabetes, high cholesterol, cigarette smoking and migraine.

Symptoms

Stroke symptoms rapidly develop within seconds to minutes. The symptoms of a stroke depend on the location of the damage in the body and the nature and severity of the symptoms generally vary and the location of the brain affected. Look for these signs to know if a friend or loved one is experiencing a stroke. If he constantly feels tingling or numbness in some parts of this body, or when limbs or one side of the face become paralyzed. He may experience blurry vision and lose consciousness. Vertigo or a spinning sensation may be felt, and he may lose a sense of coordination or balance. Aside from those, sudden mood swings, depression, and irritability may be indicative of an impending stroke. Ischemic strokes usually only affect specific areas of the brain used by the blocked artery. Hemorrhagic strokes cause more global symptoms due to bleeding and increased intracranial pressure. In most cases, the symptoms affect only one side of the body. The defect in the brain is usually on the opposite side of the body (depending on which part of the brain is affected). Loss of consciousness, headache, and vomiting usually occurs more often in hemorrhagic stroke than in thrombosis because of the increased intracranial pressure from the leaking blood compressing on the brain.

Diagnosis

When one or more of these symptoms are observed regularly, the patient should be immediately taken in for CT scan and other routine examinations. Stroke is diagnosed by: Brain Scan, CT scans or MRI scans &, Doppler ultrasound. Some of the ways by which stroke is treated is with a "clot buster", i.e. operation for removal of the blood clot or vessel obstruction, accompanied with physiotherapy and occupational therapy and secondary prevention with drugs like aspirin, blood pressure control and anticoagulation. Other types of medications help dilate the blood vessels and prevent the formation of clots. For long term rehabilitation of stroke survivors, physical therapy may be needed to help them move normally again.

Rehabilitation

Stroke rehabilitation is the process by which patients with disabling strokes undergo treatment to help them return to normal life by regaining and relearning the skills of everyday living. Nursing care is important in ensuring skin care, feeding, hydration, positioning, and monitoring vital signs such as temperature, pulse, and blood pressure. Stroke rehabilitation begins almost immediately after operation.

Prognosis

Disability affects 75% of stroke survivors enough to affect their professional careers. Stroke affect patients physically, mentally, emotionally, or a combination of the three. Some of the physical disabilities resulting from stroke include paralysis, numbness, pressure sores, pneumonia, incontinence ,inability to perform learned movements, difficulties carrying out daily activities, appetite loss, vision loss, and pain. Post-stroke emotional problems include anxiety, panic attacks, failure to express emotions, mania, apathy, and psychosis. Some of the stroke survivors suffer depression showing signs of lethargy, irritability, sleep disturbances, lowered self esteem, and withdrawal.

Prevention

primary - reduce smoking and the high risk behaviors
secondary - reduce the risk in those who already have disease and
Tertiary - reduce the risk of further strokes in people with previous history.