Stroke

Overview

A brain stroke occurs when a blood vessel carrying oxygen to different brain parts becomes obstructed. It can also occur in the case of a ruptured and bleeding internal vessel. Due to the reduced oxygen presence, the blood vessels in the brain start dying, which leads to cell death in the brain, causing a stroke.

Brain stroke is a medical condition that requires immediate medical attention within minutes of its occurrence. If left unattended, it can result in the death of the patient.

Types of Stroke:

Generally, stroke is of two kinds: hemorrhagic and ischemic. In the hemorrhagic type, the brain artery either leaks or ruptures. The leaked blood creates excess pressure on the remaining brain cells, causing a stroke. It usually happens due to a spike in blood pressure and aneurysms, which cause a bulge or stretching of the vessels.

In ischemic stroke, damage to brain cells occurs due to the obstruction of the blood arteries supplying oxygen. Blood flow is inhibited owing to the accumulation of fatty plaque deposits or particle blockage.

Other than these two, the third type of brain stroke involves a temporary blockage of the brain arteries, known as a transient ischemic attack. Usually, it resolves on its own within 5 minutes of the occurrence. However, it shouldn't be taken lightly as it indicates the likelihood of a severe attack in the future.

Based on the type of stroke and the kind of blockage, the experts prescribe treatment such as clot-removing medications, stents, thrombectomy and more.

Symptoms:

The main symptoms of stroke are:

Paralysis or numbness or inability to move parts of the face, arm, or leg - particularly on one side of the body
Confusion- including trouble with speaking
Headache with vomiting
Trouble seeing in one or both eyes
Metallic taste in mouth
Difficulty in swallowing
Trouble in walking (impaired coordination)
Dystonia
Alexia
Agnosia
The symptoms may vary depending on the type and location of the stroke. Some people may experience only a temporary disruption of blood flow to the brain, called a transient ischemic attack (TIA), which does not leave lasting symptoms but increases the risk of future strokes.

Causes:

The main causes of stroke are:

Ischemic stroke: The obstruction to blood flow is usually due to a thrombus or an embolism within the blood vessel
Hemorrhagic stroke: Hemorrhagic stroke is a type of stroke that follows bleeding in the brain
Transient Ischemic Attack: TIA is caused by the same conditions that cause an ischemic stroke, such as thrombosis, embolism, or other conditions like arterial dissection, arteries, or hypercoagulable states.

Risk factors:

The risk factors for stroke include:

Overweight
Sedentary life
Binge Drinking
Diabetes
Smoking
High blood pressure
High cholesterol
Family history of stroke
Cardiovascular diseases
Age - people above age 55 are at higher risk
Gender - men are at higher risk of stroke than women

Possible Complications:

Permanent Brain Damage

After the appearance of symptoms, the brain damage worsens every second. Depending on the part of the brain, the stroke can affect movement, coordination, vision, breathing and heart functions. Delayed treatment can impact all the associated functions, including vital life functions.

Disability

Due to the obstructed blood flow, the movement of sensory information to the other parts of the body is severely impacted. Brain damage can result in the disability of a body part, depending on the associated brain part that is injured.

Death

The brain and body's essential functions are disrupted when treatment and diagnosis are delayed. Vital functions that support the body start shutting off. The malfunction leads to heart and lung dysfunction and ceases cardiac and respiratory systems, eventually leading to the patient's death.

When to Consult a Doctor?

On Symptoms

The correct time to consult a medical expert is when the symptoms appear. Stroke can become fatal if consultation is delayed. The symptoms can range from nausea and numbness in one part of the face, eyes or hands to difficulty seeing and walking and sudden headaches with dizziness.

Individuals must seek medical help immediately after noticing these symptoms, even if they appear randomly or disappear altogether. They can use the FAST method to detect the signs, which involves analyzing the effects on the face, arms, speech, and time taken. This method involves attempting a smile, raising arms, and repeating a sentence to check the brain's cognition and consciousness.

Remember that waiting longer after a brain stroke is dangerous to the patient’s life. Delayed assistance can even result in irreversible brain damage.

• Routine Consultation

In the case of a patient's medical record with a previous brain stroke, regular consultation to check the brain's health is necessary. A brain stroke can cause damage to the areas of the brain, causing permanent disability. In addition, the injury also increases the chances of cognitive impairment. Regular checkups ensure early detection of complications.

• With Underlying Conditions

For patients with a genetic predisposition and underlying conditions like diabetes and hypertension, consultation with an expert neurologist is recommended. Not only can it prevent him/her from suffering strokes, but it can also ensure easy identification of dormant signs. Through a detailed examination of the brain, the specialist can analyse the areas requiring attention and initiate treatments accordingly.

Diagnosis:

• Physical Examination

Since stroke impacts the brain to cause dysfunction in movement and coordination, the doctor assesses a patient’s overall physical health. It will involve the evaluation of balance, sensations in arms, legs and face, vision problems and weakness in body parts.

The medical expert will also analyse the heartbeat and blood pressure to understand the root cause and severity of the condition. This analysis also involves a swallow test in which the doctor will check the patient’s ability to consume food and water without choking and coughing.

• Medical History Assessment

In this procedure, a doctor analyses the immediate causes of stroke. The expert asks questions about the activities performed at the time of the brain stroke. The patient's condition is also evaluated based on the medical record, genetic history, and existing medications.

• Blood Tests

After the preliminary analysis, medical practitioners perform several blood tests to assess the patient's current health and comorbidities. These tests include complete blood count (CBC), cholesterol level (lipid profile test), infection markers, and clotting factors. These assays enable the specialist to comprehend the clotting rate, which can obstruct normal blood flow.

• CT Scan & MRI Tests

If the exhibited symptoms indicate a stroke, the doctors recommend immediate scanning tests to determine the extent of the damage. An MRI and CT analysis provides insights into the bleeding and injury in the parts of the brain. The examination may include the injection of dye to separate the area of damage from normal parts of the brain.

• Echocardiogram & EKG

These tests determine the health of the heart. These assessments are performed to check if the underlying cause of stroke is directly linked to the clots in the heart. Echocardiogram analyses if the clots have travelled from arteries of the heart to the brain. Additionally, an electrocardiogram or EKG checks the heartbeat, including its rhythm, to rule out the possibility of arterial fibrillation.

• Cerebral Angiogram & Carotid Ultrasound

Doctors use these methods to check the clotting and functioning of the arteries carrying blood to the brain. They involve scanning the arteries of the neck, face, and brain. A doctor also requests these tests if he/she suspects narrowing or blockage of these arteries.

Treatment

Ischemic Stroke Treatment for Clots

• Emergency Medication

Plasminogen activator (tPA): A clot-dissolving medication used to reopen arteries.
Aspirin, Clopidogrel: Anticoagulants that help retard or inhibit blood coagulation.

• Endovascular Procedures or Thrombectomy

This procedure directly unblocks the clogged vessels. In one process, medications are directly inserted into the brain using a catheter after the patient is admitted to a medical facility. In another procedure, a stent removes large clots from the blocked brain vessels.

• Endarterectomy

In this method, surgeons open up the carotid artery on each side of the neck to remove the clots. It is typically performed on patients suffering from transient ischemic stroke or to reduce the risk of another brain attack.

• Carotid Angioplasty & Stenting

An inflamed balloon is placed in the narrowed carotid artery, and a stent is inserted to support the affected artery.

• Antiplatelets and Anticoagulants

The doctors suggest preventive measures by prescribing anti-clotting medications such as aspirin. In addition, these drugs are also effective in restricting clot formation by reducing platelet creation. On top of this, anticoagulants like heparins are also injected to control the future occurrence of clots in the heart and other body parts.

Hemorrhagic Stroke Treatment for Bleeding

• Emergency Transfusions

If the patient suffering from stroke is on a blood-thinning medication, doctors can provide blood transfusions. Additionally, the patient will also receive medications to reduce the blood pressure in the brain to prevent seizures.

• Clipping

To prevent the aneurysm from bursting, the surgeons place a clamp at its base. Doing this restricts blood flow to the area and prevents the haemorrhage from occurring.

• Endovascular Embolisation

With a catheter placed inside an artery, moving towards the brain, the surgeon blocks the blood flow to the aneurysm. This ensures limited blood supply to the affected area to reduce the chances of clotting.

• Surgical Arteriovenous Malformation Removal

If an abnormal tangle is present in an accessible area of the brain, the surgeons remove it to prevent stroke. It eliminates the danger of sudden vessel bursts.

• Radiosurgery

For the deep-positioned brain vessel clots, doctors use high-impact radiation beams. It ensures a minimally invasive approach to repair the malformations in the blood vessels.

Additional Information

1. Effects of stroke on the brainstem

The brainstem is the connecting link between the brain and the spinal cord. This part manages the brain's functions, including blood pressure and breathing. It also helps regulate eye movement, swallowing, hearing, and speech.

The brainstem stroke results in:

• Loss of taste and smell

• Paralysis of the voluntary muscles except that of the eyes (locked-in syndrome)

• Restricted breathing and reduced heart functions

• Difficulty in maintaining balance and coordination

• Trouble in viewing objects

• Coma

2. Effects of left and right hemisphere stroke

Depending upon the affected area, the stroke can cause a variety of side effects and dysfunctions. The after-effects of right hemisphere stroke lead to:

• Weakness or paralysis in the left part of the body

• Difficulty in noticing things and deficit in awareness (left neglect)

• Difficulty in seeing the left field of view, including depth perception

• Inability to identify body parts

• Memory issues

• Changes in behaviour, including depression

• Contrastingly, the side effects of the stroke in the left hemisphere include:

• Sensory dysfunction on the right side of the body

• Visual problems in the right field of view

• Difficulty in understanding a new language, reading and writing

• Reduced ability to retain