Medilol

Introduction:-

A stroke, previously known medically as a cerebrovascular accident (CVA), is the rapidly developing loss of brain function(s) due to disturbance in the blood supply to the brain. This can be due to ischemia (lack of blood flow) caused by blockage (thrombosis, arterial embolism), or a hemorrhage (leakage of blood) As a result, the affected area of the brain is unable to function, which might result in an inability to move one or more limbs on one side of the body, inability to understand or formulate speech, or an inability to see one side of the visual field.

The life of a person who has a stroke will change , even if they make a fully recovery. The effects of stroke are not limited to that individual, family ,friends , and carers will also be affected. Society as a whole suffers. Every year 10,000 people of working age have a stroke. The NHS spends 4% of its budget providing care for people with stroke, and a considerable proportion of spending by social services goes to providing continuing support for people at home and in residential care.

A stroke is a medical emergency. Strokes happen when blood flow to your brain stops. Within minutes, brain cells begin to die. There are two kinds of stroke. The more common kind, called ischemic stroke, is caused by a blood clot that blocks or plugs a blood vessel in the brain. The other kind, called hemorrhagic stroke, is caused by a blood vessel that breaks and bleeds into the brain. "Mini-strokes" or transient ischemic attacks (TIAs), occur when the blood supply to the brain is briefly interrupted.

A silent stroke is a stroke that does not have any outward symptoms, and the patient is typically unaware they have suffered a stroke. Despite not causing identifiable symptoms, a silent stroke still causes damage to the brain, and places the patient at increased risk for both transient ischemic attack and major stroke in the future. Conversely, those who have suffered a major stroke are at risk of having silent strokes.In a broad study in 1998, more than 11 million people were estimated to have experienced a stroke in the United States. Approximately 770,000 of these strokes were symptomatic and 11 million were first-ever silent MRI infarcts or hemorrhages. Silent strokes typically cause lesions which are detected via the use of neuroimaging such as MRI. Silent stroke are estimated to occur at five times the rate of symptomatic stroke.The risk of silent stroke increases with age but may also affect younger adults and children, especially those with acute anemia.

An ischemic stroke is occasionally treated in a hospital with thrombolysis (also known as a "clot buster"), and some hemorrhagic strokes benefit from neurosurgery. Treatment to recover any lost function is termed stroke rehabilitation, ideally in a stroke unit and involving health professions such as speech and language therapy, physical therapy and occupational therapy. Prevention of recurrence may involve the administration of antiplatelet drugs such as aspirin and dipyridamole, control and reduction of hypertension, and the use of statins. Selected patients may benefit from carotid endarterectomy and the use of anticoagulants

What is stroke???

Most strokes happen when blood can't reach a part of your brain. When blood flow to the brain stops, brain cells in that part of the brain may die. Your brain controls how you move, feel, think and behave. A stroke may damage any of these functions.

Effects Of A Stroke?

The following are the most common effects of stroke:

• Weakness or paralysis on one side of the body
• Problems with speech and language
• Poor balance or clumsy movement
• Not knowing what happens on one side of the body
• Trouble swallowing
• Problems with bladder or bowel control
• Problems with memory, thinking or problem solving
• Poor vision and/or changes in vision
• Numbness
• Problems getting around and caring of yourself

What actually is a stroke?

A stroke is what happen when the brain is damaged as the result pf a problem with its blood supply. Each part of the brain is responsible for a particular function, so the symptom that result

What is a mini stroke?

Mini stroke is the term that is sometimes given yo a mild stroke that recovers very quickly, although not as a TIA. Seek medical attention as quickly as possible.

Are all strokes are same?

The cause of strokes are many and various. Every individual is different and therefore no one stroke is ever the same as another. The pattern of recovery is different, too. This is what makes it so difficult to predict what is going to happen. Always treat with caution any advice given that seems to be very definite.I have lost count of the number of time I've been told that "he was only given a few days to live, and look at him now some years later". Prediction are particularly difficult to make in first few weeks after a stroke. As time passes. However. It should be possible for a stroke specialist to make a fairly reasonable estimate of the longer term outlook.

Definition:-

Neurological deficit of cerebrovascular cause that persists beyond 24 hours or is interrupted by death within 24 hours

This definition was supposed to reflect the reversibility of tissue damage and was devised for the purpose, with the time frame of 24 hours being chosen arbitrarily. The 24-hour limit divides stroke from transient ischemic attack, which is a related syndrome of stroke symptoms that resolve completely within 24 hours. With the availability of treatments that, when given early, can reduce stroke severity, many now prefer alternative concepts, such as brain attack and acute ischemic cerebrovascular syndrome (modeled after heart attack and acute coronary syndrome respectively), that reflect the urgency of stroke symptoms and the need to act swiftly

Classification Stroke can be classified into two major categories

Ischemic

Hemorrhagic

 

Ischemic:-

In an ischemic stroke, blood supply to part of the brain is decreased, leading to dysfunction of the brain tissue in that area.

Reasons:-

There are four reasons why this might happen:

1. Thrombosis (obstruction of a blood vessel by a blood clot forming locally)

2. Embolism (obstruction due to an embolus from elsewhere in the body, see below),

3. Systemic hypoperfusion (general decrease in blood supply, e.g., in shock)

4. Venous thrombosis

Stroke without an obvious explanation is termed "cryptogenic" (of unknown origin); this constitutes 30-40% of all ischemic strokes.

classification is based on clinical symptoms as well as results of further investigations; on this basis, a stroke is classified as being due to

(1) thrombosis or embolism due to atherosclerosis of a large artery,

(2) embolism of cardiac origin,

(3) occlusion of a small blood vessel,

(4) other determined cause,

(5)undetermined cause (two possible causes, no cause identified, or incomplete investigation

Hemorrhage:-

Intracranial hemorrhage is the accumulation of blood anywhere within the skull vault. A distinction is made between intra axial hemorrhage (blood inside the brain) and extra axial hemorrhage (blood inside the skull but outside the brain). Intra-axial hemorrhage is due to intraparenchymal hemorrhage or intraventricular hemorrhage (blood in the ventricular system). The main types of extra-axial hemorrhage are epidural hematoma (bleeding between the Dura mater and the skull), subdural hematoma (in the subdural space) and subarachnoid hemorrhage (between the arachnoid mater and pia mater). Most of the hemorrhagic stroke syndromes have specific symptoms (e.g., headache, previous

Symptoms:-

When brain cells are deprived of oxygen, they cease to perform their usual tasks. The symptoms that follow a stroke depend on the area of the brain that has been affected and the amount of brain tissue damage.

Small strokes may not cause any symptoms, but can still damage brain tissue. These strokes that do not cause symptoms are referred to as silent strokes. According to The U.S. National Institute of Neurological Disorders and Stroke (NINDS), these are the five major signs of stroke:

1. Sudden numbness or weakness of the face, arm or leg, especially on one side of the body. The loss of voluntary movement and/or sensation may be complete or partial. There may an associated tingling sensation in the affected area.

2. Sudden confusion or trouble speaking or understanding. Sometimes weakness in the muscles of the face can cause drooling.

3. Sudden trouble seeing in one or both eyes

4. Sudden trouble walking, , loss of balance or coordination

dizziness

5. Sudden, severe headache with no known cause

　

Associated symptoms:-

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 the brain.

If symptoms are maximal at onset, the cause is more likely to be a subarachnoid hemorrhage or an embolic stroke.

Causes :-

Blockage of an artery:-

The blockage of an artery in the brain by a clot (thrombosis) is the most common cause of a stroke. The part of the brain that is supplied by the clotted blood vessel is then deprived of blood and oxygen. As a result of the deprived blood and oxygen, the cells of that part of the brain die and the part of the body that it controls stops working. Typically, a cholesterol plaque in a small blood vessel within the brain that has gradually caused blood vessel narrowing ruptures and starts the process of forming a small blood clot.

Risk factors for narrowed blood vessels in the brain are the same as those that cause narrowing blood vessels in the heart and heart attack (myocardial infarction). These risk factors include:

high blood pressure (hypertension),

high cholesterol,

diabetes, and

Smoking.

Embolic stroke:-

Another type of stroke may occur when a blood clot or a piece of atherosclerotic plaque (cholesterol and calcium deposits on the wall of the inside of the heart or artery) breaks loose, travels through the bloodstream and lodges in an artery in the brain. When blood flow stops, brain cells do not receive the oxygen and glucose they require to function and a stroke occurs. This type of stroke is referred to as an embolic stroke. For example, a blood clot might originally form in the heart chamber as a result of an irregular heart rhythm, such as occurs in atrial fibrillation. Usually, these clots remain attached to the inner lining of the heart, but occasionally they can break off, travel through the blood stream, form a plug (embolism) in a brain artery, and cause a stroke. An embolism can also originate in a large artery (for example, the carotid artery, a major artery in the neck that supplies blood to the brain) and then travel downstream to clog a small artery within the brain.

Cerebral hemorrhage:-

A cerebral hemorrhage occurs when a blood vessel in the brain ruptures and bleeds into the surrounding brain tissue. A cerebral hemorrhage (bleeding in the brain) causes stroke symptoms by depriving blood and oxygen to parts of the brain in a variety of ways. Blood flow is lost to some cells. As well, blood is very irritating and can cause swelling of brain tissue (cerebral edema). Edema and the accumulation of blood from a cerebral hemorrhage increases pressure within the skull and causes further damage by squeezing the brain against the bony skull further decreasing blood flow to brain tissue and cells.

Subarachnoid hemorrhage:-

In a subarachnoid hemorrhage, blood accumulates in the space beneath the arachnoid membrane that lines the brain. The blood originates from an abnormal blood vessel that leaks or ruptures. Often this is from an aneurysm (an abnormal ballooning out of the wall of the vessel). Subarachnoid hemorrhages usually cause a sudden, severe headache, nausea, vomiting, light intolerance, and a stiff neck. If not recognized and treated, major neurological consequences, such as coma, and brain death may occur.

Vasculitis:-

Another rare cause of stroke is vasculitis, a condition in which the blood vessels become inflamed causing decreased blood flow to brain tissue.

Migraine headache:-

There appears to be a very slight increased occurrence of stroke in people with migraine headache. The mechanism for migraine or vascular headaches includes narrowing of the brain blood vessels. Some migraine headache episodes can even mimic stroke with loss of function of one side of the body or vision or speech problems. Usually, the symptoms resolve as the headache resolves.

Diagnosis:-

A stroke is a medical emergency. Anyone suspected of having a stroke should be taken to a medical facility immediately for evaluation and treatment. Initially, the doctor takes a medical history from the patient if possible or from others familiar with the patient if they are available. Important questions include what the symptoms were, when they began, if they were getting better, worse or staying the same. Past medical history adds important information looking for risk factors for stroke and for medications that can cause bleeding (for example, warfarin [Coumadin], clopidogrel [Plavix], prasugrel [Effient]).

Physical examination is key in confirming the parts of the body that have stopped functioning and may help determine what part of the brain has lost its blood supply. If available, a neurologist, a doctor specializing in disorders of the nervous system and diseases of the brain, can assist in the diagnosis and management of stroke patients.

Just because a person has slurred speech or weakness on one side of the body does not necessarily signal the occurrence of a stroke. There are many other possibilities that can be responsible for these symptoms. Other conditions that can mimic a stroke include:

brain tumors,

brain abscess (a collection of pus in the brain caused by bacteria or a fungus),

migraine headache,

bleeding in the brain either spontaneously or from trauma,

meningitis or encephalitis,

an overdose of certain medications, or

an electrolyte imbalance in the body. Abnormal concentrations (too high or too low) of sodium, calcium, or glucose in the body may also cause changes in the nervous system that can mimic a stroke.

In the acute stroke evaluation, many things will occur at the same time. As the physician is taking the history and performing the physical examination, nursing staff will begin monitoring the patient's vital signs, performing blood tests, and performing an electrocardiogram (EKG or ECG).

Part of the physical examination that is becoming standardized is the use of a stroke scale. The American Heart Association has published a guide to the examination of the nervous system to help health care practitioners determine the severity of a stroke and whether aggressive intervention may be warranted.

There is a narrow time frame to intervene in an acute stroke with medications to reverse the loss of blood supply to part of the brain (please see TPA below). The patient needs to be appropriately evaluated and stabilized before any clot-busting drugs can be potentially utilized.

　

Computerized tomography:-

In order to help determine the cause of a suspected stroke, a special X-ray test called a CT scan of the brain is often performed. A CT scan is used to look for bleeding or masses within the brain that may cause symptoms that mimic a stroke, but are not treated with thrombolytic therapy with TPA.

MRI scan:-

Magnetic resonance imaging (MRI) uses magnetic waves rather than X-rays to image the brain. The MRI images are much more detailed than those from CT, but due to the length of time to do the test and lack of availability of the machines in many hospitals, is not a first line test in stroke. While a CT scan may be completed within a few minutes, an MRI may take more than an hour to complete. An MRI may be performed later in the course of patient care if finer details are required for further medical decision making. People with certain medical devices (for example, pacemakers) or other metals within their body, cannot be subjected to the powerful magnetic field of an MRI.

Other methods of MRI technology:-

An MRI scan can also be used to specifically view the blood vessels non-invasively (without using tubes or injections), a procedure called an MRA (magnetic resonance angiogram). Another MRI method called diffusion weighted imaging (DWI) is being offered in some medical centers. This technique can detect the area of abnormality minutes after the blood flow to a part of the brain has ceased, whereas a conventional MRI may not detect a stroke until up to six hours after it has started, and a CT scan sometimes cannot detect it until it is 12 to 24 hours old. Again, this is not a first line test in the evaluation of a stroke patient, when time is of the essence.

Computerized tomography with angiography:-

Using dye that is injected into a vein in the arm, images of the blood vessels in the brain can give information regarding aneurysms or arteriovenous malformations. Moreover, other abnormalities of brain blood flow may be evaluated. With faster machines and better technology, CT angiography may be done at the same time as the initial CT scan to look for a blood clot within an artery in the brain.

CT and MRI images often require a radiologist to interpret their results.

Conventional angiogram:-

An angiogram is another test that is sometimes used to view the blood vessels. A long catheter tube is inserted into an artery in the groin or arm and threaded into the arteries of the brain. Dye is injected while X-rays are taken and information can be obtained about blood flow in the brain. The decision to perform CT angiography versus conventional angiography depends upon a patient's specific situation and the technical capabilities of the hospital.

Carotid Doppler ultrasound: -

A carotid Doppler ultrasound is a non-invasive test that uses sound waves to look for narrowing or stenosis and decreased blood flow in the carotid arteries (the major arteries in the front of the neck that supply blood to the brain)

Heart tests:-

Certain tests to evaluate heart function are often performed in stroke patients to search for the source of an embolism. Electrocardiograms (EKG or ECG) may be used to detect abnormal heart rhythms like atrial fibrillation that are associated with embolic stroke.

Ambulatory rhythm monitoring may be considered if the patient complains of palpitations or passing out episodes (syncope) and the doctor cannot find reason for it on the EKG. The patient can wear a Holter monitor for 1-2 days and sometimes longer looking fro a potential electrical conduction problem with the heart.

Echocardiograms or ultrasounds of the heart can help evaluate the structure and function of the heart including the heart muscle, valves and the motion of the heart chamber when the heart beats. As well, specifically for stroke patients, this test may be able to find blood clots within the heart and the presence of a patent foramen ovale, both potential causes of stroke.

Blood tests:-

In the acute situation, when the patient is in the midst of a stroke, blood tests are done to check for anemia, kidney and liver function, electrolyte abnormalities and blood clotting function.

In other situations, when time is not of the essence, similar blood tests may be done. In addition, screening test for inflammation may be considered including an ESR (erythrocyte sedimentation rate) and CRP (C-reactive protein). These are non specific tests that may give direction to medical care.

Treatment

Tissue plasminogen activator (TPA):-

There is opportunity to use alteplase (TPA) as a clot-buster drug to dissolve the blood clot that is causing the stroke. There is a narrow window of opportunity to use this drug. The earlier that it is given, the better the result and the less potential for the complication of bleeding into the brain.

Present American Heart Association guidelines recommend that if used, TPA must be given within 4 1/2 hours after the onset of symptoms. for patients who waken from sleep with symptoms of stroke, the clock starts when they were last seen in a normal state.

TPA is injected into a vein in the arm but, the time frame for its use may be extended to six hours if it is dripped directly into the blood vessel that is blocked requiring angiography, which is performed by an interventional radiologist. Not all hospitals have access to this technology.

TPA may reverse stroke symptoms in more than one-third of patients, but may also cause bleeding in 6% patients, potentially making the stroke worse.

For posterior circulation strokes that involve the vertebrobasilar system, the time frame for treatment with TPA may be extended even further to 18 hours.

Heparin and aspirin:-

Drugs to thin the blood (anticoagulation; for example, heparin) are also sometimes used in treating stroke patients in the hopes of improving the patient's recovery. It is unclear, however, whether the use of anticoagulation improves the outcome from the current stroke or simply helps to prevent subsequent strokes (see below). In certain patients, aspirin given after the onset of a stroke does have a small, but measurable effect on recovery. The treating doctor will determine the medications to be used based upon a patient's specific needs.

Managing other Medical Problems:-

Blood pressure will be tightly controlled often using intravenous medication to prevent stroke symptoms from progressing. This is true whether the stroke is ischemic or hemorrhagic.

Supplemental oxygen is often provided.

In patients with diabetes, the blood sugar (glucose) level is often elevated after a stroke. Controlling the glucose level in these patients may minimize the size of a stroke.

Patients who have suffered a transient ischemic attacks, the patient may be discharged with blood pressure and cholesterol medications even if the blood pressure and cholesterol levels are within acceptable levels. Smoking cessation is mandatory.

Complications:-

A stroke can become worse despite an early arrival at the hospital and appropriate medical treatment. Progression of symptoms may be due to brain swelling or bleeding into the brain tissue.

It is not unusual for a stroke and a heart attack to occur at the same time or in very close proximity to each other.

During the acute illness, swallowing may be affected. The weakness that affects the arm, leg, and side of the face can also impact the muscles of swallowing. A stroke that causes slurred speech seems to predispose the patient to abnormal swallowing mechanics. Should food and saliva enter the trachea instead of the esophagus when eating or swallowing, pneumonia or a lung infection can occur. Abnormal swallowing can also occur independently of slurred speech.

Because a stroke often results in immobility, blood clots can develop in a leg vein (deep vein thrombosis). This poses a risk for a clot to travel upwards to and lodge in the lungs - a potentially life-threatening situation (pulmonary embolism). There are a number of ways in which the treating physician can help prevent these leg vein clots. Prolonged immobility can also lead to pressure sores (a breakdown of the skin, called decubitus ulcers), which can be prevented by frequent repositioning of the patient by the nurse or other caretakers.

Stroke patients often have some problem with depression as part of the recovery process, which needs to be recognized and treated.

The prognosis following a stroke is related to the severity of the stroke and how much of the brain has been damaged. Some patients return to a near-normal condition with minimal awkwardness or speech defects. Many stroke patients are left with permanent problems such as hemiplegia (weakness on one side of the body), aphasia (difficulty or the inability to speak), or incontinence of the bowel and/or bladder. A significant number of persons become unconscious and die following a major stroke.

If a stroke has been massive or devastating to a person's ability to think or function, the family is left with some very difficult decisions. In these cases, it is sometimes advisable to limit further medical intervention. It is often appropriate for the doctor and the patient's family to discuss and implement orders to not resuscitate the patient in the case of a cardiac arrest, since the quality of life for the patient would be so poor. In many cases, this decision is made somewhat easier if the patient has had a discussion with family or loved ones before an illness has occurred.

Prevention:-

Given the disease burden of strokes, prevention is an important public health concern. Primary prevention is less effective than secondary prevention (as judged by the number needed to treat to prevent one stroke per year).Recent guidelines detail the evidence for primary prevention in stroke. Because stroke may indicate underlying atherosclerosis, it is important to determine the patient's risk for other cardiovascular diseases such as coronary heart disease. Conversely, aspirin confers some protection against first stroke in patients who have suffered a myocardial infarction or patients with a high cardiovascular risk

Rehabilitation:-

When a patient is no longer acutely ill after a stroke, the health care staff focuses on maximizing the individuals functional abilities. This is most often done in an inpatient rehabilitation hospital or in a special area of a general hospital. Rehabilitation can also take place at a nursing facility.

The rehabilitation process can include some or all of the following:

1. speech therapy to relearn talking and swallowing;

2. occupational therapy to regain as much function dexterity in the arms and hands as possible;

3. physical therapy to improve strength and walking; and

4. family education to orient them in caring for their loved one at home and the challenges they will face.

The goal is for the patient to resume as many, if not all, of their pre-stroke activities and functions. Since a stroke involves the permanent loss of brain cells, a total return to the patient's pre-stroke status is not necessarily a realistic goal in many cases. However, many stroke patients can return to vibrant independent lives.

Depending upon the severity of the stroke, some patients are transferred from the acute care hospital setting to a skilled nursing facility to be monitored and continue physical and occupational therapy.

Many times, home health providers can assess the home living situation and make recommendations to ease the transition home. Unfortunately, some stroke patients have such significant nursing needs that they cannot be met by relatives and friends and long-term nursing home care may be required.

By

Mahrukh Majeed

Bpd01093269

Doctor of pharmacy

University of Lahore