Stroke: Causes, Treatment & Prevention!

Stroke occurs when the blood supply to the brain or the part of the brain is cut off, due to which less oxygen is supplied to the brain & as a result the brain cells die, therefore stroke is a medical emergency.

TYPES OF  STROKE

  • Ischemic Stroke: When blood supply to the brain tissue is decreased leading to cell death & dysfunction in the particular area. It has four causes:
  1. Thrombosis: Obstruction due to a blood clot
  2. Embolism: Obstruction due a mass that has traveled from somewhere else.
  3. Systemic Hypoperfusion: General decrease in blood supply, like in shock.
  4. Cerebral Venous Sinus Thrombosis.
  • Hemorrhagic Stroke: Bleeding that occurs due to a burst vein. It has two subtypes:
  1. Intracerebral Hemorrhage: Bleeding within the brain itself.
  2. Subarchanoid Hemorrhage: Bleeding between the internal meninges, it still occurs in the skull, but outside of the brain.

SIGNS & SYMPTOMS OF STROKE

  • Sudden onset of facial weakness & numbness
  • Drifting of one arm
  • Difficulty in speech
  • Facial palsy
  • Initial muscle weakness followed by muscle overactivity.
  • If the brain stem is involved, some symptoms that are seen are:
  • Altered smell, taste, sensation.
  • Drooping of the eyelids & weakness of the eye muscles.
  • Decreased reflexes
  • Problems in maintaining balance
  • Altered breathing & heart rate
  • In case the cerebral cortex is involved some symptoms are;
  • Difficulty in verbal expression, reading & writing.
  • Motor speech disorder
  • Memory problems
  • Confusion
  • Lack of awareness
  • Vertigo
  • Fainting.

COMPLICATIONS

  • Pressure ulcers
  • Pneumonia
  • Incontinence
  • Inability to perform learned movements
  • Difficulty carrying out daily activities
  • Loss of vision & speech
  • Anxiety & Panic attacks
  • Mania, apathy & psychosis
  • Seizures & convulsions
  • Depression
  • Dementia
  • Paralysis
  • Deep Vein Thrombosis
  • Pulmonary embolism
  • Coma
  • Death

CAUSES & RISK FACTORS

  • In thrombotic stroke, plaque formation in the vein occurs due to which clots are formed.
  • Some diseases & risk factors that contribute to such kind of a stroke are;
  • Sickle cell anemia, inflammation of the veins, atherosclerosis, vasoconstriction of the arteries in the brain, etc.
  • In an embolic stroke, particles of mass, like air, fat, or bacteria that are traveling in the blood, can cause a blockage in the brain.
  • Risk factors include, arrhythmia, Deep vein thrombosis, infective inflammation of the endometrium of the heart, calcium deposits in the heart valve.
  • Cerebral hypoperfusion in which blood supply is cut off to all parts of the brain can be due to; myocardial infarction, pulmonary embolism, accumulation of fluid in the heart sac, hypoxia.
  • Intracerebral hemorrhage is due to hypertension, some risk factors are; trauma, bleeding disorders, illicit drug use, etc.
  • Some other risk factors & diseases that can increase the chances of stroke are;
  • Diabetes Mellitus
  • End stage Kidney disease
  • Heavy alcohol use & smoking
  • Lack of physical activity & being obese
  • Consumption of red meat
  • Migraine.

DIAGNOSIS OF STROKE

  1. Physical examination of the symptoms which can give an estimation of the severity of the stroke.
  2. Imaging Tests in ischemic & hemorrhagic stroke are as follows:
  • For diagnosing ischemic stroke in emergency settings
  1. CT scans (without contrast enhancements)
    sensitivity= 16% (less than 10% within first 3 hours of symptom onset)
    specificity= 96%
  2. MRI scans
    sensitivity= 83%
    specificity= 98%
  • For diagnosing hemorrhagic stroke in emergency settings
  1. CT scans (without contrast enhancements)
    sensitivity= 89%
    specificity= 100%
  2. MRI scan
    sensitivity= 81%
    specificity= 100

When a stroke is diagnosed various other tests are conducted for further classification to determine the cause:

  • Ultrasound for narrowed carotid arteries.
  • ECG to identify arrhythmia or clots in the heart.
  • Holter Monitor study.
  • Angiogram of the cerebral vasculature.
  • Blood tests for determining blood cholesterol & activity of clotting factors.

TREATMENT

  • For controlling hypertension, anti-hypertensives of the class Beta blockers, ACE inhibitors, CCBs are given.
  • Reduction of blood cholesterol levels by prescription of statins.
  • Anti-diabetic medications to control blood sugar levels.
  • Anti-coagulants are given to prevent formation of clots.
  • Blood thinning medication like Aspirin.
  • Surgery for narrowed carotid artery by angioplasty can prevent future episodes of stroke.
  • Thrombectomy, a mechanical procedure used for breaking down clots in the blood vessels.
  • In a medical procedure, an anti-coagulant medication is injected through a catheter in an artery, which travels to the site of clot in the brain, to break down the clot.
  • Craniectomy, a surgical procedure which involves the removal of one side of the skull to prevent complications arising from swelling in the brain.
  • Surgery to manage burst aneurysm, for removing pooled up blood & management of the burst artery.

MANAGEMENT & PREVENTION OF STROKE

  • In patients who have suffered from stroke, rehabilitation therapy is followed up, which may include;
  • Physical therapy
  • Occupational therapy
  • Speech & language therapy
  • Use of wheelchairs & ankle foot orthoses.
  • Motor learning
  • Assistance in learning activities of daily lives, in other words, speech, eating, movement, reading, etc.
  • Assistance in eating food by inserting a nasogastric tube.
  • Electrical stimulation & magnetic stimulation for the patient.
  • Modernistic therapies like virtual reality & robot assistance.
  • For prevention of stroke;
  • Proper diet, that is low on sugar, salt, fats & cholesterol.
  • Maintaining a healthy weight & physical exercise.
  • Management of other diseases & conditions.