What are Strokes?
When, for some reason, there is impairment in the flow of blood to the brain, glucose and oxygen essential for its functioning cannot reach the brain. This disruption causes the cells in that part of the brain to die. This is called a Cerebro-Vascular Accident or CVA. In layman’s language it’s called a “stroke”.
Note: The big three to easily identify a stroke – if a person is experiencing sudden unjustifiable uneasiness, he/she should be asked to carry out three simple tasks; smile, speak a simple sentence and raise both arms. If the person cannot do any of these, then he/she has suffered a stroke and needs immediate medical attention and hospitalization. Delay can prove fatal.
Symptoms of Strokes
The symptoms of a Stroke would depend on which part of the brain has been affected, i.e. which cells in the brain have died due to lack of glucose and oxygen. The symptoms would also depend on the extent of damage. The symptoms of “silent” or mild strokes are not visible. But in this case too brain damage takes place without outward signs. The visible signs of a stroke are:
1) Voluntary movements may cease partially or completely
2) Drooling due to stiffness of the facial muscles
3) Partial loss of eyesight
4) Severe headache for no apparent reason
5) One-sided numbness of face, leg, arm
6) Hampered ability of understanding others and confusion
7) Hampered ability to speak clearly
8) Sudden giddiness and lack of coordination of motor ability.
Diagnosis of Strokes
As a stroke pertains to death of some cells in the brain, it can lead to other complications. Hence, this needs to be considered an emergency situation, requiring prompt hospitalization and treatment. A cardiologist and neurologist would have to undertake a physical examination, ask questions of those accompanying the patient as to the symptoms they had noticed, etc.
Common tests: Simultaneous with the physical examination and medical history, blood tests, electrocardiogram (ECG), etc are also undertaken.
Stroke scale: This is used to check the performance of the nervous system, as well as to evaluate the damage caused by the stroke, its severity, and whether surgery is imperative.
Computerized tomography (CT) scan: A CT scan of the brain would show the presence of blood clot, growths, bleeding within the brain, etc which could be the possible cause of the stroke. This would also show the exact location of the damage to the brain.
MRI scan: Magnetic resonance imaging (MRI) gives a greater amount of digital imaging data for analysis than a CT scan. But as the test takes longer to perform and provide results, this is not used as the first mode of diagnosis.
MRA: Magnetic Resonance Angiogram is a non-invasive method of checking for clots in blood vessels. This does not use either injections or tubes. This diagnostic technique is so accurate; that any abnormalities in the flow of blood to the brain are visible within a few hours of the episode. Whereas, a CT scan sometimes takes 24 hours to show accurate results. But, despite its accuracy it is still not the first level of testing for strokes as the cost is prohibitive.
CTA: Computerized tomography with angiography is a method where a vein is injected with a dye and then a brain CT scan is conducted. This shows any abnormal formations or clots in the bloodstream going towards the brain.
Angiogram: In this method a dye is injected into an artery (in groins) through a catheter and X-rays are taken as the dye moves along the bloodstream. Being an invasive testing method, it is used infrequently for diagnosing a stroke.
Carotid Doppler Ultrasound: This is a non-invasive method of testing, where sound waves are digitally converted to images on a screen. The images would show any constriction of the arteries, especially the carotid artery. The carotid
Heart tests: Tests like Echocardiogram or Electrocardiogram are conducted in order to check for inflammation of the heart as a cause of lack of blood to the brain. These tests can detect any abnormality in the functions of the heart.
Blood tests: Arterial inflammation can be detected in blood tests by checking for the C-reactive protein and rate of sedimentation, as these tend to thicken the blood, thus causing a stroke. Also, blood tests help to eliminate other concurrent ailments like kidney malfunction, anemia, etc.
Caution: Patients with metals like pacemakers in their bodies are advised not to undergo the MRI test. A CT scan for such patients should be sufficient.
Caution about misdiagnosis: Sometimes another disease with similar symptoms can be misdiagnosed as a stroke. They are – brain abscess, brain tumor, meningitis, brain hemorrhage, drug reactions in case of overdoses, encephalitis, severe cases of migraine, sudden changes in levels of calcium, glucose and sodium in the body, etc.
Causes of Strokes
There are various causes for the prevalence of strokes:
A) Stroke due to thrombosis: The biggest cause of a stroke is a blood clot in a major artery leading to the brain. The clot would mean blockage of the artery leading to deprivation of glucose and oxygen causing death of brain cells. A clot is usually formed in a blood vessel which has already become narrow due to factors like hypertension, diabetes, etc. These factors are then aggravates further by the habit of smoking.
B) Embolic stroke: Embolism means blockage or plugging. Sometimes calcium or cholesterol (fats) particles form plaques on the inner walls of the arteries causing blockages. If this happens in the carotid artery leading to the brain, a stroke is unpreventable. This is called an embolic stroke. Also, a clot originally formed in the heart but travels up the artery would cause a stroke.
C) Cerebral hemorrhage: Sometimes a cerebral blood vessel itself might rupture. Then the blood would spread into the brain tissue surrounding this blood vessel. This would in turn deprive glucose and oxygen to that part of the brain causing a stroke, called cerebral hemorrhage.
D) Subarachnoid hemorrhage: “Arachnoid membrane” refers to the lining of the brain. When a blood vessel in this lining hemorrhages or ruptures, leaking blood into the surrounding areas, it leads to shortage of glucose and oxygen to that area of the brain, with the same result. This can result in a coma or “brain death”.
E) Vasculitis or migraines: Vasculitis refers to the inflammation of blood vessels and slower flow of blood to the brain causing a stroke. A migraine is caused due to blood vessels becoming narrow. This is another reason for a stroke.
F) A transient ischemic attack (TIA): This is called a “mini-stroke” and is caused by a short period of loss of blood to the brain resulting in dizziness and temporary loss of vision or “blackout”. The effect of the stroke lasts for less than a day, unlike other strokes, but to prevent a major stroke, a TIA needs to be treated immediately.
G) Drug abuse: Strokes in youngsters occur more because of illegal use of harmful substances like heroin, cocaine, opium, etc.
H) Heredity: Some blood types have a tendency towards excessive clotting of the blood causing a stroke. Excess of the chemical homocystine in the body is considered the culprit here. This can cause a stroke in any age group.
Types of Strokes
The four main types of strokes are:
A) Lacunar stroke – dying of brain tissue by narrowing of small arteries
B) Atherosclerosis – hardening of the arteries directly connected to the brain due to calcium or cholesterol deposits
C) Brain embolism – blood clot in the heart traveling towards the brain causing a stroke
D) Hemorrhagic stroke – caused by the rupture and bleeding of the blood vessel in the brain.
Treatment of Strokes
A stroke requires immediate medical attention as it can prove fatal.
Initial medical attention: This would involve keeping the patient flat on the back for even blood circulation, watching to see that the patient doesn’t choke on his vomit if occurring, etc.
Tissue plasminogen activator (TPA): This is an injectible clot-dissolving drug used when a blood clot is the cause of the stroke. Obviously, this cannot be used in the case of hemorrhagic stroke.
Anticoagulants: Oral blood thinners like heparin and aspirin or anti-platelet drugs like clopidogrel or dipyridamole are administered to speed up the process of dissolving the clot.
Caution: TPA and any kind of anti-clotting agents should not be used in the case of stroke due to bleeding of artery.
Carotid endarterectomy: If the carotid artery has ulceration causing it to narrow and block the normal flow of blood, carotid endarterectomy becomes necessary.
Artificial ventilation: Oxygen should be administered if considered necessary by the attending doctors, depending on the response to treatment.
Other medical problems: Simultaneously, other medical problems like cholesterol levels, blood sugar levels, blood pressure, etc have to be monitored and controlled to prevent complications.
Rehabilitation: Restoring the normal functions of the patient is the key goal of the treatment. To this end, the convalescence and rehabilitation process in a suitable nursing home is very crucial. This would include speech therapy, physiotherapy and occupational therapy, educating the family, caregivers, etc.
Living with Strokes
A stroke, even a mild one, can be disabling to a large extent. Swallowing can become difficult after a stroke. Speech becomes slurred. There is drooling and assistance while eating may be required. Convalescence and rehabilitation are lengthy processes and need professional help from caregivers. Long periods of immobility can cause bed-sores and ulcers on the skin. If the patients cannot move on their own, caregivers have to reposition them. Lack of activity can lead to depression in some patients. In severe cases, loss of control over the bladder or bowel movements can occur, causing further discomfort. A major stroke can prove fatal. A stroke can not only adversely affect the patient’s life, but also cause a lot of problems for the family members as well.
Prevention of Strokes
The only way to prevent a stroke is to prevent or avoid the risk factors causing it, like:
A) Smoking should be stopped completely
B) Prevent high blood pressure
C) Prevent diabetes mellitus
D) Avoid fatty and oily foodstuffs to prevent cholesterol
E) Regular medical checkups can detect problems at onset
F) Regular exercise keeps the circulatory system in good working condition.