Ischemic stroke

Ischemic Stroke-Concept-Signs and Symptoms-Risk Factors-TreatmentConcept: 
The ischemic stroke is occlusion of a blood vessel that stops blood flow to a specific region of the brain, interfering with the neurological functions dependent on the region affected, producing a deficit symptoms or characteristics, around 80% of strokes are ischemic.

Ischemia can be permanent or temporary. In temporary cases blood start flowing back after some time. Such Ischemia is popularly known as "threat of stroke" (or Transient Ischemic Attack in medical terms). This is important because it is a sign that permanent ischemia can occur at any time, if nothing is done to avoid them patient may get attacked by stroke.

Signs and Symptoms: 

Difficulty in speaking or understanding, loss of sensation in the limbs and balance unfold in minutes and get worse over the hours. The lack of irrigation in the brain may have given some warning sign weeks or even months before in the form of "mini attacks" in which signs appears and disappears suddenly.

Depending on the cause of the obstruction Arteriovenous Ischemia can be of three types:
Thrombotic: Formation of blood clot in an artery of the brain due to Atherosclerosis accounts for 60% of cases.
Embolism: in 20% of cases the clot has formed in

another part of the body and travel to clog an artery that carries blood from to the brain.
Circulatory failure: Deficiency in pumping ability of heart or shock may lead to deficiency in head circulation, this explains why a heart attack can lead to a stroke.

The CVA (Cerebrovascular Accident) is manifested differently on each patient because the symptoms depend on the area of ​​the brain affected and  the size of the affected area, the type (ischemic or hemorrhagic), and the patient's general condition, age, etc.. In general, the main feature is the speed with which the changes appear; within seconds to hours (abruptly or rapidly progressive). We draw attention to the most common changes: Weakness or numbness of a limb or on one side of the body - The acute onset of a weakness in one of the limbs (arm, leg) or face is the most common symptom of stroke. Ischemia can mean an entire cerebral hemisphere or only a small, specific area. They can occur in different ways by presenting greater weakness in the face and arm to leg, or leg weakness greater than in the arm or face, or weakness may be accompanied by other symptoms. These differences depend on the location of ischemia and the extent of brain damage.
Visual disturbances - loss of vision in one eye, mainly acute alarm patients and often leads them to seek medical evaluation. The patient may have a feeling of "shadow'' or" curtain "to see or may have transient blindness (amaurosis fugax)."
Sensory Loss - The numbness usually occurs along with the decrease of strength (weakness), confusing the patient; sensitivity is subjective.
Language and speech (aphasia) - It is common to observe changes of language and speech, so some patients present with short talks, causing much frustration (consciousness of effort and difficulty speaking), some patients have a different language disorder of speaking long sentences with fluency, making little sense and there will be great difficulty in understanding their language. Family and friends may describe this symptom to the doctor as an attack of confusion or stress.

Risk Factors: 

Blood Pressure: 

This is the main risk factor for stroke. Hypertension accelerates the process of atherosclerosis, and could lead to a rupture of a blood vessel or an ischemia.

Heart Disease: 

Any cardiac disease, in particular those producing arrhythmias, may cause a stroke. If the heart is not beating right, there may be a difficulty for the blood to reach the brain and other organs and can lead to ischemia. The main situations in which this can occur are: arrhythmias, myocardial infarction, Chagas disease and valve problems.

Cholesterol

Cholesterol is a substance that is present in our entire body, present in animal fats. It is produced mainly in the liver and acquired through diet rich in fats. Its altered levels, especially elevated LDL (bad cholesterol present in saturated fats, manly those of animal origin such as meats, egg yolk etc.) Or the reduction of HDL (good cholesterol) are related to development of atherosclerotic plaques.

Excessive use of alcohol: 

When a person has the habit of heavy use of alcohol for a long time, cholesterol levels rise. Moreover, one has a greater propensity to hypertension.

Diabetes:

Diabetes is a disease in which blood sugar (glucose) in the blood is high. The measurement of blood glucose is made by examining blood glucose levels. If a carrier of this disease has controlled his blood sugar and if he would have a stroke, it will certainly be less severe than in an individual whom blood sugar is not controlled.

Age: 

The older the person, the greater will be the likelihood of having a stroke. But always remember that young people may also get a stroke.

Previous history of vascular disease: 

People who have had strokes, "threat of stroke," myocardial infarction (heart) diseases of vessels (Thrombosis etc..), are more likely to have a stroke.

Obesity: 

In general obesity increases the risk for diabetes, hypertension and atherosclerosis; thus indirectly increases the risk of stroke.

Highly concentrated blood: 

This occurs, for example, when the person is severely dehydrated or there is an increase in red blood cells. The latter occurs in people who have chronic lung disease (ie, for many years), or who live in high altitudes

Contraceptives: 

The uses of hormonal contraceptives in higher doses may increase the likelihood of a stroke.

Sedentary lifestyle:

 Lack of physical activity can lead to problems such as obesity, which predisposes to diabetes, hypertension and increased cholesterol.

Smoking: 

Smoking should be avoided as it is harmful to health in all aspects, especially in those people who already have other risk factors. Cigarette smoking accelerates the process of atherosclerosis, the blood becomes thicker (concentrated) over the years (increasing the amount of red blood cells) and increasing the risk of hypertension.

Conduct Immediate: 

Stroke is an emergency, like the heart attack. In other words, if you suspect stroke, take the patient immediately to the Emergency Room. Avoid self and unprescribed medications, As for example, many times the blood pressure is high and the so the anxiety and medicine may increase the risk of progressing the stroke. If you give high dose of antihypertensive medicine it will lower the blood pressure and low pressure hamper the flow of blood to the brain hence, complicating the picture. At the hospital, the attending physician should worry among several parameters, for example breathing and adequate hydration, proper diet (either orally or through the blood), care to prevent sores (bed sores) due to persistence presence of the patient in the same position , blood pressure control and temperature (avoiding infectious complications, mainly pulmonary), prevention of thrombosis in the leg veins, etc.

 Specific treatment: 

correction of disorders of blood coagulation, preventing vasospasm, avoid increasing twilight zone (due to edema) fight the free radicals. We must understand that "each case is different." Some may require surgical treatment, such as drainage of a hematoma (blood clot) or to correct a malformation. Treatment should be early in order to obtain better results. After discharge, the patient should be monitored. The attending physician must give the prescription of drugs to be taken, as well as all necessary guidelines.

Treatment: 

There are some areas in various parts of the world were special special stroke cells are created which are called "Stroke Units" just like "Coronary Units" which are created for heart patients. These units are specialized in the treatment of ischemic stroke, using standardized protocols and behaviors that involve a multidisciplinary team in the treatment and patient care.

Medication and Dosage: 

a. Decrease blood viscosity: aims at improving the factors influencing the adequacy of cerebral circulation, such as hematocrit, fibrinogen, aggregation of erythrocytes and platelets etc.

b. Expansion volume: It will decrease hematocrit, there will be a decrease in viscosity, improving the conditions of the microcirculation.. This is due to the combination of phlebotomy and colloid (dextran 40, albumin and plasma). But decrease in hematocrit affect the oxygen transport capability of blood. So caution should be made.

c. Antiplatelet drugs: These drugs are those that prevent platelets aggregation and clot formation. dipyridamole, ticlopidine and pentoxifylline are the antiplatelet drugs. Its main indications are prevention after TIA episode and prophylaxis in patients with atherothrombotic disease confirmed.

• sulfinpyrazone: derivative of phenylbutazone. Inhibits platelet cyclooxygenase. The oral absorption is with peak plasma concentration between one and two hours after intake and half-life is two to three hours. The usual dose is 200 mg, 6/6 hours. Its side effect is gastrointestinal bleeding.

• Trifluxal: leads to blocking of cyclooxygenase and phosphodiesterase, more potent than aspirin.

• Indobufeno: It inhibits cyclooxygenase reversibly. Have lower incidence of side effects than aspirin.

• Aspirin (ASA) is the drug of choice for stroke. Use ticlopidine in cases of intolerance or failure to respond to Aspirin. Dipyridamole is recommended to prevent thrombosis related to prosthetic materials.

• Ticlopidine: is one of the most commonly used drugs for prevention after TIA, especially in young adults. Its main side effect is a diarrheal syndrome caused by intestinal mucosal absorptive imbalance.

• Pentoxifylline: is the preferred drug for use in the elderly, especially in vascular dementia and in cases of symptomatic carotid atherothrombotic disease in the elderly. May cause leukopenia.

• Clorpidogrel: newly developed drugs with encouraging prophylactic results. It has the advantage that it can be used in single dose of 75 mg / day.

d. Anticoagulant medications: before the use of anticoagulants, a physician should remember following points

• We should not use anticoagulants in severe cases of stroke because of higher risk of major hemorrhagic transformations;

• We must have strict control of blood pressure in patients with anticoagulants;

• We repeat CT (cranial CT) in case of large infarcts, to verify the possibility of bleeding between the second and fourth day, or in case of worsening;



the most common anticoagulants are heparin, thrombolytics and anticoagulants.

• Heparin: indicated in the case of evolution of ischemic stroke, ischemic lesions associated with arterial or cardiac sources of embolism, the presence of rheumatic heart disease, myocardial infarction or atrial fibrillation, cases of recurrent TIA or when there is failure in treatment with anticoagulants. Complications with the use of heparin is bleeding at sites of preexisting vascular damage (ulcers, hemorrhoids, uremia, liver diseases), thrombocytopenia, osteoporosis, alopecia, hypersensitivity reactions and hyperaldosteronism.

• Thrombolytics: thrombolytic agents are drugs that promote fibrinolysis in tissue by several mechanisms. The main complications are cerebral hemorrhage and systemic bleeding. They are currently the most effective drugs for treatment of ischemic stroke in its hyperacute phase.

• Anticoagulants: oral anticoagulants block the oxidation reduction of vitamin K by modifying the synthesis of it which depends on factors (factors II, VII, IX and X), and the proteins C and S. There are factors that alter the effectiveness of anticoagulants, such as liver disease, vitamin A in the diet, medications that may alter the absorption, albumin binding, metabolism or excretion. The indications for use of oral anticoagulants are acute myocardial infarction, bacterial endocarditis, prosthetic heart valves, atrial fibrillation and rheumatic valvular disease. In the case of AMI oral anticoagulant should be given for three to six months, followed by antiplatelet agents. Anticoagulants are contraindicated during the first and third trimesters of pregnancy, due to fetal malformations and bleeding, respectively.


Prophylactic measures: Studies and research indicate that leading a healthy life, taking care of food and exercising regularly can reduce the risk of stroke by 80%. Keeping blood pressure under control; Avoid excess salt intake; Moderate intake of alcoholic beverages; Take two to four capsules of grape seed powder daily, do not smoke; Control weight; Having a healthy diet, eating fruits, vegetables and fiber and avoid excessive fat intake and avoid excess fried foods, exercise regularly or at least do hiking; Avoid stress whenever possible and try to have a healthy life.

Dra. Sarah Raquel Cavalcanti dos Santos
About Author: General medical, critical and reflective that can act with competence and scientific ethics in the health-disease through health promotion, prevention, protection and rehabilitation of the individual, family and community, through training excellence and committed to citizenship Follow her @ Medical Education and Health Encyclopedia | Facebook

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