A stroke is a condition of reduced or interrupted blood supply to the brain. This results into
inadequate oxygen and nutrients supply to the brain. Lack of oxygen to the brain causes death of neurons (brain cells). A stroke is a medical emergency requiring prompt treatment. Early medical intervention can minimize the damage and potential complications.
The following signs and symptoms are suggestive of stroke and duration of these can affect the treatment options.
- Slurring of speech or trouble in speaking. There could be mental confusion
- Paralysis or numbness of the face, arm or leg: Patient may develop sudden weakness, numbness or paralysis of limbs or face. Mostly this symptom is seen on one side of the body. The patient may show drooping on one side of the face while trying to smile.
- Headache: Sudden, severe headache usually with nausea or vomiting, dizziness and altered consciousness may indicate onset of stroke.
- Blurring of vision, double vision or blackened vision.
- There could be difficulty in walking due to loss of balance or loss of coordination.
An acronym to remember is “FAST”
- Face: Drooping of face in an attempt to smile
- Arms: Ask the patient to raise both the arms and see if any of the arm drift downwards or unable to lift the arm.
- Speech: Slurred or strange speech on repeating the words.
- Time: In presence of any of these three signs immediately rush the patient to the hospital for further assessment & management. Time of medical care is key to the successful treatment of stroke.
A stroke may be due to blocked arterial blood supply or bursting of the blood vessel. Most of the stroke (85%) are due to blockage of the brain vessels (ischemic stroke).The remaining cases are due to leaking or bursting of the brain artery (haemorrhagic stroke ).There could be temporary interruption of blood flow to brain without any permanent damage (transient ischemic attack or TIA).
Ischemic stroke is caused due to blockage or narrowing of arteries in the brain. These blocks are due to formation of clots in the vessel disrupting blood flow to the brain. There are fatty deposits on the lining of the vessel walls (atherosclerosis). These fatty deposits can cause ischemic stroke due to two types of obstruction
- Formation of thrombus (blood clot) in the brain vessels
- Formation of embolism: Blood clot is formed at some other location like heart, neck and travels through the artery until reaches to small vessel of the brain to obstruct it.
Brain hemorrhages can be due many conditions that include uncontrolled high blood pressure, use of anticoagulants (blood thinners) and weak spots in blood vessels (aneurysms). Hemorrhagic stroke are of the following types:
- Intracerebral haemorrhage: A blood vessel in the brain ruptures and bleed into the surrounding brain tissues damaging the brain cells.
- Subarachnoid haemorrhage: A vessel on or near the surface of brain bursts and spills into the space between the surface of brain and skull.
Transient Ischemic Attack (TIA):
It is also known as ministroke. It is a temporary decrease in blood supply that may last as little as five minutes. It is due to blood clot reducing blood flow to the brain but there is no permanent tissue damage and no lasting symptoms. A person developing TIA has increased risk of full blown stroke in future.
The following factors are associated with the risk of stroke.
- Lack of physical activity (sedentary life)
- Binge drinking
- Illicit drugs ( cocaine & methamphetamines)
- High blood pressure
- High cholesterol
- Sleep apnoea
- Cardiac diseases (heart failure, heart attack)
- Family history of stroke
Other potential risk factors include age above 55 years, men are at higher risk than women, and use of birth control pills
A stroke can lead to temporary or permanent disability depending on duration of loss of blood flow to the brain. The following complications can be seen in stroke.
- Paralysis: Patient may develop weakness or complete paralysis of one side of the body.
- Difficulty in talking (Dysarthria):The muscle of the mouth or throat may be affected in stroke to cause difficulty in talking. Patient may have slurring of speech or even strange speech.
- Difficulty in swallowing (Dysphagia)
- Difficulty in language like understanding, reading, writing etc.(Aphasia)
- Partial or complete loss of memory.
- Emotional disturbances including depression
- Pain or tingling sensation in limbs.
- Behavioural disturbances. Patient may be withdrawn, unsocial or more impulsive.
Most of the strategies for stroke prevention are similar as that of prevention of heart diseases.
- Control of high blood pressure
- Decrease in cholesterol
- Reduced intake of saturated fats in diet
- Quit tobacco
- Control of diabetes
- Maintain optimum body weight
- High intake of fruits, vegetables, nuts, and whole grains
- Regular exercise
- Reduce alcohol intake
The main approach for the diagnosis of stroke is based on physical examination by the doctor, measurement blood pressure, laboratory tests for blood sugar and few biochemical parameters, CT scan and MRI of the brain. CT and MRI are the imaging tests to find the damage of the brain tissue. The doctor may advise to go for CT angiography to identify the site of block or haemorrhage in the brain.
The treatment of stroke is based on the type of stroke i.e. ischemic or haemorrhagic, duration of symptoms onset and associated complications.
The treatment of ischemic stroke is to start clot bursting drugs within 4.5 hours of the onset to restore blood flow to the brain. An early treatment helps in better clinical outcome and prevent further complications. The patient is administered Intravenous injection of thrombolytic to dissolve the clot.
Sometimes the doctors perform specific procedures (endovascular) directly at the blocked site in the brain to restore the blood flow. All these procedures are done by highly qualified neuro-physicians or neurosurgeons. These endovascular procedures are more effective than drugs.
Preventive Medications for Ischemic stroke:
Patients with past episode of ischemic stroke or TIA are recommended to take medicines to reduce their risk of further strokes. The drugs (blood thinners) included are as follows:
- Anti-platelets: These drugs prevent the formation of thrombus or clot
- Anticoagulants: These drugs disrupts the process of blood clotting
Emergency treatment of this stroke is mainly directed to control the bleeding and reducing the pressure in the brain. The patients are given transfusion of blood products to counteract effects of antiplatelets or anticoagulant drugs. Additionally, patients are given treatment to lower the pressure in the brain and also the drugs to prevent potential risk of seizures.
After control of bleeding, the treatment is mainly based on supportive medical care. In cases of severe bleeding patient may require to undergo surgery.
Recovery & Rehabilitation:
The prime goal in the management of stroke is to facilitate faster and complete recovery of neurological functions. This is initiated immediately after the treatment before patient is discharged from the hospital. The patient requires to continue the rehabilitation program in the unit of same hospital, outpatient unit or at home. The following team may be involved in rehabilitation based on stage of recovery.
- Physiotherapist to improve muscular tone and strength.
- Occupational therapist to improve on memory impairment
- Speech pathologist to improve speech and language impairment
- Social worker
- Psychologist or psychiatrist to help improve the emotional and behavioural disturbances.
Stroke is a leading cause of long term disability across the globe. However, it is reported that 10 percent of stroke survivors make an almost complete recovery, while another 25 percent recover with only minor impairments.