Discuss platelet aggregation. Find out what it is and what is the norm?

Platelet aggregation is necessary so that when the skin is damaged, when blood vessels rupture, and during external environment blood begins to be released, the process of coagulation was carried out - bleeding was stopped and the subsequent healing of the wound.

Without platelet aggregation, wounds would not heal, for the reason that the blood from the damaged area would gush without stopping. And even a small wound, if this process is disturbed, can bring many problems.

Platelet aggregation - what is it?

As already indicated, without platelet aggregation, blood will not clot at the site of injury. How does this process take place? First, a rupture of the vessel is formed.

The body understands that it is time to act. Platelets rush to the site of damage in large numbers, which stick together.

When there are more clots, new platelets are added to them, attaching to the walls of blood vessels. Tau and a crust forms on the scratch and wound.

That is, the role of aggregation is to "patch" the damaged vessel, stopping the bleeding and providing tightness conditions for the internal environment of the body. Thanks to this process, the wounds heal and the person subsequently does not even remember them.

Platelet norm

In order for platelet aggregation to be normal, it is necessary to ensure the intake of a sufficient amount of vitamins, microelements, and macroelements into the body.

This will support normal level hemoglobin in the blood, when the level of iron meets the standard, and the blood is able to carry oxygen to organs and tissues.

When examining blood samples, the time taken for the formation of clots from platelets should be taken into account. The laboratory assistant evaluates the speed of cell movement and their transformation in real time. The norm is from 10 seconds to one minute.

Platelet analysis

When should I pay attention to platelet aggregation?

1. If you notice bruises on the body, although there were no significant blows. In this case, there is a suspicion of defective platelet function.
2. If the wounds do not heal well. This means that platelets can hardly cope with the task assigned to them - to stick together at the sites of damage. The result is constantly bleeding wounds that slowly heal and heal.
3. If often there is blood from the nose. Another sign of poor clotting.
4. If there is swelling of the tissues. This means that the aggregation rate is too high, which is the risk of vascular problems.

What does the analysis look like? First, the lab technician takes a blood sample. Further, in laboratory conditions, an inductor is introduced into the blood (a tool that allows you to start natural reaction blood clotting). At this stage, the monitoring and measurement of belt indicators takes place.

How to prepare for the analysis?

1. Do not take medication without consulting your doctor. Aspirin preparations are subject to a ban, since they affect platelets, make blood thinner, and complicate clotting. The result of the analysis will not correspond to reality.
2. The day before the test, do not eat anything fatty. Fatty foods also affect blood clotting.
3. Do not eat anything for 12 hours before the test. You can drink regular clean water. It is better to take the analysis on an empty stomach in the morning.
4. Keep calm. Remember, any excitement can affect physical performance.
5. Don't get busy sports training the last day before the test.
6. It is forbidden to smoke, drink alcohol, drink coffee, eat garlic a day before the visit to the laboratory.
7. If inflammatory processes occur, the result of the analysis may be incorrect. If you have a cough (a sore throat), an abscess of the skin, joints hurt and inflammation is the reason for this, it is better to take the test later.

women during menstrual cycle it is better not to take the test, because during this period of time platelets are less active according to natural causes.

Changes during pregnancy

During pregnancy, women change not only the hormonal background, but in general the course of most processes. The result may also be poor clotting blood.

Symptoms of poor aggregation during pregnancy:

1. there is blood from the nose;
2. bruises appear on the body;
3. gums bleed;
4. swelling of soft tissues occurs;
5. appears vascular network(risk of developing blood clots).

Peculiarities

It is important to understand that moderate deviations from the norm are considered natural during pregnancy. Moreover, deviations can be observed in both directions - increased formation of blood clots or, on the contrary, reduced.

Why does pregnancy affect blood composition and platelet function? This is due to the placental circulation and the peculiarities of the blood supply to the extremities, when in general the blood circulation becomes more complicated.

What to do if platelet aggregation is reduced?

With reduced aggregation, prolonged bleeding is observed, and vascular fragility becomes the main factor in the formation internal bleeding, which externally appear as bruises that occur without previous strokes.

First, you need to avoid injury. Moreover, injuries are not only abrasions and scratches, but also blows, because when they occur without damaging the skin, the structure of the vessels is disturbed, they tear and form internal bleeding.

Secondly, you need to remember that some drugs affect the natural aggregation.

For example, aspirin drugs such as indomethacin and dipyridamole should be taken in small amounts and only when really needed. In some cases, they can be replaced by a more gentle alternative, depending on each specific case. Usually, aspirin drugs thin the blood, which causes poor clotting.

Also, do not eat too salty or too spicy food. Normally, such food is digested quite normally and does not harm health, but its systematic intake in excess of the norm also thins the blood and worsens aggregation.

The diet should include organic products- fruits, vegetables, milk. Apples, beets, buckwheat, meat, fish, nuts, in which high content gland.

Causes of increased aggregation

Increased aggregation - dangerous phenomenon, which can occur in the body under favorable conditions for this.

In the risk group, first of all, hypertension - people with diseases of cardio-vascular system.

Few people take into account the fact that with diseases of the kidneys and stomach there are problems with the patency of blood vessels, the blood thickens.

You also need to pay attention to nutrition - high pectin content, lack of iron, constant consumption of fatty foods are risk factors.

Increased platelet aggregation is a consequence of the removal of the spleen, sepsis.

Symptoms of the disease

Thick blood, which moves slowly through the vessels, becomes the main symptom. How can you tell if your circulation is good? It basically gives out negative factor skin condition. If sagging, cellulite appears in uncharacteristic places, the skin is pale - perhaps the blood is too thick and stagnates.

With increased aggregation, a feeling of numbness appears (especially for the fingers) and swelling.

Why is it dangerous?

Increased aggregation is dangerous in that when it occurs, the risk of developing thrombosis, heart attack and stroke increases.

Norm in a child

Platelets in the blood of children are usually contained either within the normal range or elevated. The same can be said about their aggregation - the rate of "growth" of cells can be more significant, exceeding the limits of the norms.

Doctors calculate normal platelet levels based on the child's age, weight, and the time the test was taken.

For a newborn child, the norm is 100-420 thousand. In adolescence, girls have 75-220 thousand platelets is considered the norm. Aggregation speed from 10 seconds to 40 is the norm. For adolescence aggregation up to one minute is considered the norm.

medicalkon.com

Platelet aggregation: what is it, blood test, norm

Platelet aggregation, according to the logic of the name, is their association in order to stop bleeding. But this is only one, albeit important, blood clotting factor, which has a numerical value.

The main function of platelets is to participate in the vascular-platelet (microcirculatory) mechanism of stopping bleeding, that is, in creating a plug (thrombus) that closes the hole in the vascular wall resulting from damage. Thrombus formation occurs as a result of adhesion (sticking to a damaged vascular wall) and platelet aggregation.

As usual, for the ability to aggregate platelets, there are norms in which cell adhesion has a positive role. However, in some cases, the aggregation ability of platelets can play a negative role by disrupting the nutrition of cells of important organs due to the formation of blood clots.

What is platelet aggregation

This type of hemostasis is typical for small vessels with small caliber and low blood pressure. For more large vessels the mechanism of coagulation is characteristic, that is, the activation of blood coagulation.

Hemostasis system and blood clotting

Hemostasis is a complex physiological processes in the body, thanks to which the liquid aggregate state of the blood is preserved, and blood loss is minimized in case of violation of the integrity of the vascular bed.

Disturbances in the functioning of this system can manifest as hemorrhagic conditions ( increased bleeding), and thrombotic (a tendency to form small blood clots that prevent normal blood flow due to increased platelet aggregation).

For reference. In the normal functioning of the hemostasis system, damage to the vessel activates a sequential chain of events leading to the formation of a stable thrombus and the cessation of bleeding. Important role this mechanism is played by vascular spasm, which provides a decrease in blood flow at the site of injury, adhesion and aggregation of platelets, as well as activation of the coagulation cascade.

To stop bleeding in small-caliber vessels, a microcirculatory mechanism for stopping bleeding is sufficient. The cessation of bleeding from larger vessels is impossible without the activation of the blood coagulation system. However, it must be understood that the full maintenance of hemostasis is possible only with the normal functioning and interaction of both mechanisms.

In response to damage to the vessel occurs:

• vascular spasm;
• release from damaged cells of the endothelium lining the vessels from the inside, VWF (von Willebrand factor);
• start of the coagulation cascade.

Endothelial cells are endothelial cells that line inner surface vessel, are able to produce anticoagulants (limiting the growth of a thrombus and controlling platelet activity) and procoagulants (activate platelets, contributing to their full adhesion). These include: von Willebrand factor and tissue factor.

That is, after a spasm occurs in response to damage to the vessel and procoagulants are released, active process creating a platelet plug. First of all, platelets begin to stick to the damaged area of ​​the vascular bed (manifestation of adhesive properties). In parallel, they secrete biologically active substances, contributing to increased vascular spasm and a decrease in blood supply to the damaged area, they also release platelet factors that trigger the coagulation mechanism.

Among the substances secreted by platelets, it is necessary to single out ADP and thromboxane A2, which contribute to the active aggregation of platelets, that is, sticking to each other. Due to this, the thrombus begins to rapidly increase in size. The process of platelet aggregation continues until the formed clot reaches a sufficient caliber to close the hole formed in the vessel.

In parallel with the formation of a thrombus, due to the work of the coagulation system, fibrin is released. The strands of this insoluble protein tightly braid platelets, forming a complete platelet plug (fibrino-platelet structure). Further, platelets secrete thrombosteine, which contributes to the contraction and tight fixation of the cork, and its transformation into a platelet thrombus. This is a temporary structure that firmly closes the damaged area of ​​the vessel and prevents blood loss.

For reference. Platelet activation decreases with distance from the damaged area of ​​the vessel. Platelets that have undergone partial activation, that is, those located at the edge of the clot, are detached from it and returned to the bloodstream.

Further destruction of the formed thrombus, limiting its growth, as well as preventing the formation of small blood clots (increased platelet aggregation) in intact vessels, is carried out by the fibrinolysis system.

Blood test for platelet aggregation

If it is necessary to evaluate the functional activity of platelets, an analysis is performed with their induced aggregation - an aggregogram. In fact, this study allows you to graphically display the ability of platelets to active adhesion and aggregation.

Aggregatogram is performed on a special automatic aggregometer. The analysis is carried out after the addition of aggregation stimulants to the patient's platelet-rich plasma.

Platelet aggregation inducers are divided into:

• weak (adenosine diphosphate (ADP) in small doses, adrenaline);
• strong (ADP in high doses, collagen, thrombin).

As a rule, platelet aggregation is carried out with ADP, collagen, adrenaline and ristomycin (antibiotic ristocetin). The study of platelet activity in the presence of ristocetin is important research in the diagnosis of hereditary hemorrhagic thrombocytopathies (von Willebrand's disease and Bernard-Soulier syndrome).

In these conditions, platelet aggregation is impaired after activation with ristocetin. Under the influence of other inductors (collagen, ADP), activation occurs.

Rules for preparing for taking an analysis

Smoking is prohibited one hour before the test. Within half an hour before taking the material, the patient should be at rest.

Attention. It is important to remember that the results of the platelet activation test change dramatically under the influence of medicines that can affect blood clotting.

The attending physician and laboratory staff must be informed about the medications taken by the patient. High concentrations anticoagulants can reduce platelet aggregation. Antiaggregants dramatically reduce all types of activation of platelet aggregation. The use of antiplatelet agents should be stopped 10 days before the analysis, and non-steroidal anti-inflammatory drugs - at least three days.

Also violate the aggregation ability of platelets:

• high dosages of diuretics (furosemide) and beta-lactams (penicillin, cephalosporins),
• beta-blockers (propranolol),
• vasodilators,
• calcium channel blockers,
• cytostatics,
• antifungal drugs (amphotericin),
• antimalarials.

They can also slightly reduce platelet aggregation:

• Luke,
• garlic,
• ginger,
• turmeric,
• coffee,
• fish oil.

Induced platelet aggregation. Decoding, norm and pathology

More often, the results of the study are recorded as a percentage. Normal platelet aggregation with:

• ADP 5.0 µmol / ml - from sixty to ninety;
• ADP 0.5 µmol/ml - up to 1.4 to 4.3;
• adrenaline - from forty to seventy;
• collagen - from fifty to eighty;
• ristocetin - from fifty-five to one hundred.

It must be remembered that:

• activation by ristomycin is an indirect reflection of von Willebrand factor activity;
• ADP - platelet aggregation activity;
• collagen induction - the integrity of the vascular endothelium.

The percentage value indicates the degree of light transmission of the plasma after adding the aggregation inductor to it. Platelet-poor plasma is taken as light transmission - 100%. Conversely, platelet-rich plasma is 0%.

Example: an increase in the amplitude of the light transmission curve (an increase in values ​​above the norm) with the addition of an ADP inductor at a high dose (5 μmol / ml) indicates an increased platelet aggregation activity, that is, after the addition of the inductor, platelets actively stick together and plasma light transmission increases.

Aggregation during pregnancy

Normal platelet aggregation during pregnancy ranges from thirty to sixty percent. IN last trimester there may be a slight increase in platelet aggregation.

Decrease in values ​​indicates high risk bleeding during childbirth, and a pronounced increase - about the risk of thrombosis in the postpartum period, as well as a possible miscarriage of the fetus (threat of self-abortion).

Indications for analysis

• hemorrhagic disorders (increased bleeding);
• thrombophilia (a bleeding disorder with an increased risk of thrombosis);
• severe atherosclerosis;
• diabetes mellitus;
• before carrying out surgical interventions;
• during pregnancy;
• when monitoring the effectiveness of anticoagulant and antiplatelet therapy.

Also, this study is important in the diagnosis of hereditary hemorrhagic thrombocytopathies.

Increased platelet aggregation. Causes

Similar violations in the analyzes are typical for:

• thrombophilia (a clotting disorder characterized by a tendency to form blood clots);
• DM (diabetes mellitus);
• severe atherosclerosis;
• ACS (acute coronary syndrome);
• malignant neoplasms;
• viscous platelet syndrome;
• severe dehydration (dehydration thrombophilia).

Most often, blood clots form in deep veins. lower extremities. The disease is manifested by arching pains in the legs, aggravated by walking, fatigue, swelling, pallor and cyanosis of the affected limb.

Initial thrombosis affects mainly the veins of the gastrocnemius muscle, then with the progression of the disease, blood clots spread higher, affecting the knee, thigh and pelvis. The spread of thrombosis and the increase in the size of the thrombus increases the risk of pulmonary thromboembolism.

Reasons for the decrease in aggregation

The decrease in aggregation is typical for:

• aspirin-like syndrome;
• myeloproliferative diseases;
• treatment with drugs that reduce platelet aggregation;
• uremia.

In von Willebrand's disease (manifested by nasal, gastrointestinal, uterine bleeding, hemorrhages in the muscles during injuries, easy hematoma formation) will be:

• sharply impaired activation by ristocetin;
• preserved induction of ADP, collagen and adrenaline;
• von Willebrand factor deficiency.

Bernard-Soulier syndrome (profuse bleeding from mucous membranes) oral cavity, nose, prolonged bleeding from wounds, hemorrhagic rash, extensive hematomas), is also characterized by a sharp decrease in platelet activation by ristomycin, while maintaining normal ADP induction, etc. In this disease, von Willebrand factor activity is normal.

Glantsman's thrombasthenia is manifested by hemorrhages in the joints, prolonged bleeding from wounds, hemorrhagic rash, severe nosebleeds. In the aggregation a sharp decline activation of platelets by ADP, adrenaline and collagen. Induction with ristomycin is not impaired.

In Wiskott-Aldrich syndrome, thrombocytopenia, eczema, and frequent purulent infections are observed. The analyzes are characterized by a decrease in the reaction with collagen, adrenaline and the absence of a second wave with ADP.

serdcet.ru

Platelet aggregation in blood clotting

Platelets are small blood cells whose main function is to protect the body from internal and external bleeding. The blood stops due to the possibility of gluing blood cells and the appearance of blood clots in the vessels. This is called platelet aggregation. Cells glued to each other cling to the wall blood vessel. Other elements of blood grow on them, and all this leads to the formation of a large thrombus, which completely closes the flow of blood into the vessel, and the bleeding stops. It is on the speed of this seemingly simple operation that depends human life.

Platelets and blood clotting

Platelet aggregation in the human body occurs only as needed. But there are pathological cases when an unauthorized process of gluing them can harm the body, and even lead to death. It's about about the formation of blood clots, which can cause malnutrition of vital internal organs with the development of such serious diseases and conditions of the body as hemorrhagic stroke, thrombophlebitis, thrombosis of the main veins, myocardial infarction.

That is why it is important that the rate of platelet aggregation in the blood is not exceeded. This is especially important for people who have a hereditary predisposition to the formation of blood clots, or in the presence of serious illnesses.

Norm

To determine the rate of platelet aggregation is carried out general analysis blood. In this case, it is necessary to donate blood from a vein. At the time of its collection, platelets do not receive signals from the body about the need to stop bleeding. In vitro - this is the name of the process of studying platelet aggregation. The name is Latin, and in translation means "on glass". The conditions in which the analysis is carried out in the laboratories are trying to bring them as close as possible to the realities of work. human body.

To check the ability of platelets to start the formation of a thrombus in time and only if necessary, they use substances that are present in the human body, that is, they are not alien to platelets - adrenaline, ristocetin, collagen. In this case, all these substances and hormones of the human body are inductors that trigger the necessary for laboratory research, processes of blood cells. To determine the norm of platelets and pathology, the light density of blood plasma is used. The platelet adhesion rate is calculated in the first minute of the test.

The result of the analysis depends on the substance of the blood, which acted as an inductor. For example, with adrenaline, the rate of platelet content in the blood should be in the range of 35 - 92.5 percent.

If blood clotting during pregnancy and not only, with adrenaline is lowered, there is a certain pathological process in the body that needs to be diagnosed.

For ADP (adenosine diphosphate), the normal range is 30.7 - 77.7 percent. For collagen, the normal range is 46.4 - 93.1 percent.

Training

If it is wrong to prepare for a blood test, its effectiveness will be a big question:

• 7-10 days before donating blood, exclude the use of aspirin-type medicines, as well as antidepressants. If it is impossible to stop taking them, it is necessary to warn the laboratory employee about this.
• There must be at least 12 hours between blood donation and the last meal. fatty food should be excluded from the diet even earlier, as it gives a large error in performance.
• A day or two before the analysis, exclude sports, do not lift weights.
• For 24-48 hours, there should be no garlic in food, it is forbidden to drink coffee and alcoholic drinks. Smoking is excluded.
• In the presence of inflammatory processes in the body, the test is postponed until complete recovery.

Purpose

Passing a test to determine a blood clotting disorder is mandatory for patients who are prescribed medications that prevent blood from clotting. An analysis for platelet aggregation is carried out in order to diagnose the required dosage.

Decryption

The study of platelet aggregation is carried out using three inducers simultaneously to identify the main factor that activates the process of clumping of blood cells. Significance for diagnosis is a deviation from the norm. What does it mean if platelet aggregation with adp is increased? It is adenosine diphosphate that affects the behavior of platelets and the start of the process of their gluing.

A decrease in platelet aggregation in the blood can be observed with the right medication, or the presence of diseases in the body, which are collectively called thrombocytopathy.

Etiology of thrombocytopathy

This set of diseases has a hereditary and acquired nature of appearance. According to medical statistics, about 10% of the total population of the planet have this pathology. The main characteristic of thrombocytopathy is functional impairment blood cells in the process of accumulation of certain blood substances.

In fact, this is the inability of blood to clot, due to the absence of a formed blood clot, which causes external and heavy internal bleeding.

First signs pathological process begin to appear in childhood, and have clinical picture long non-healing wounds, large edema at the site of minor bruises. In girls, the presence of thrombocytopathy is expressed in long-lasting and heavy menstruation. The result of pathology is the development of anemia.

The inactivity of blood cells to form blood clots can be caused due to a severe viral or infectious disease, as well as under the influence of regular intake of certain medical preparations.

Secondary thrombocytopathy

The causes of thrombocytopathy are leukemia, anemia of the pernicious form, the development of myeloma. It is also observed when kidney failure, disruption endocrine system.

Other causes of secondary thrombocytopathy:

• Atherosclerosis.
• Hypertension.
• Heart attack.
• Formation of blood clots in arteries abdominal cavity.
• Stroke.
• Diabetes.

Platelet behavior during pregnancy

During pregnancy, the number of blood cells can differ significantly from the norm. Manifestation - constant small bleeding, bruising. ABOUT possible risk discovery of bleeding is necessary in without fail warn medical staff who will take birth.

Increased platelet aggregation during pregnancy is observed mainly in the first trimester and is caused by toxicosis, during which the body loses a large number of liquids.

If the indicator exceeds the norm, there is a risk of unwanted blood clots. The result - complications during pregnancy up to spontaneous miscarriage.

A moderate increase in the level of aggregation in a pregnant woman is the norm, and it is caused by the need to nourish the placenta with blood. Normal indicators it is customary to consider from 30 to 60 percent of any inductors.

The delivery of a blood test to determine the degree of platelet aggregation during pregnancy is required:

• At frequent pregnancies but the inability to bear fruit.
• At therapeutic methods infertility treatment.
• Before you start taking contraceptives, and after completion.
• As one of the measures for diagnosing the state of the body during pregnancy planning.

A timely analysis of platelet aggregation during pregnancy makes it possible to predict the development possible complications and appoint preventive measures.

sostavkrovi.ru

Hyperaggregation of platelets during pregnancy - what is it

What is platelet hyperaggregation? Platelets are blood cells that take part in the process of coagulation of fluids of a biological nature. They are the main controllers of the process of stopping bleeding, as well as strengthening the walls of blood vessels. It is they who take part in the process of platelet aggregation and are responsible for the occurrence of such a condition as hyperaggregation. And if the first state is quite natural for the body healthy person, then the second requires certain treatment.

Platelet aggregation - what is it

It is scientifically known what the process of platelet aggregation means. By it is meant the procedure for gluing cells, as a result of which a cork is formed that closes the place where the wound was inflicted (no matter what size). After that, blood cells usually adhere to the walls of blood vessels and form a blood clot, which prevents profuse bleeding from developing - whether it be a small scratch or a large wound. However, there are points that require control of the ability of platelets to aggregate.

These include:

• strong activity of blood cells;
• frequent and profuse bleeding.

Given the activity of platelets, there are several types of their ability to aggregate.

These include:

1. Spontaneous - no inductors are required to determine it, it is enough to place blood from a vein into a test tube heated to 37 ° C.
2. Induced - involves the addition of inductors of a different nature to the blood for more accurate diagnosis certain diseases. The analysis in this case takes place in the laboratory.
3. Moderate - observed in women in an "interesting" position, that is, at the time of pregnancy.
4. Low - contributes heavy bleeding and requires medical intervention to prevent its consequences.
5. Increased - creates a risk of blood clots, which can lead to blockage of blood vessels and cause a stroke or heart attack.

In fact, the phenomenon of aggregation in healthy body speaks about the correctness of the work defensive reaction his body. As a result of this process, a person is protected from large blood loss.

Hyperaggregation of platelets, its causes and symptoms

The phenomenon of hyperaggregation suggests an increase in the viscosity of the genetic material, which is usually characterized by its slow mobility but rapid clotting (given the fact that the rate of blood clotting is 2 minutes).

Most often, this phenomenon is observed in the case of the development of the following pathological conditions:

• with a constant increase blood pressure;
• as a result of diabetes various types;
• with cancerous diseases of the blood, kidneys, stomach;

• in the case of a phenomenon such as thrombocytopathy;
• with changes in atherosclerotic vessels.

If platelet hyperaggregation is detected during the study, we can talk about certain risks for the patient if he is not going to control the process and follow drug treatment prescribed by the doctor.

These risks include:

1. The occurrence of a heart attack is a disease affecting the heart muscles and characterized by circulatory failure.
2. The occurrence of a stroke is a violation of the processes of blood circulation in the brain.
3. Blockage of veins in the legs.

The state of hyperaggregation at the time of pregnancy

It is very important to monitor the phenomenon of platelet hyperaggregation during pregnancy. In this state, it is extremely important for a woman that the test results are within reasonable indications, since not only her safety for nine months depends on this, but also generic activity in which she will have to take an active part.

The main causes of the phenomenon of hyperaggregation at the time of pregnancy are:

1. Severe toxicosis, characterized by constant vomiting, frequent stool leading to dehydration.
2. Pathological conditions leading to an increase in the level of platelet blood cells.

Treatment medications in such cases, it is prescribed only when it does not help special diet recommended for pregnant women.

Usually experts advise to lean:

• for egg and dairy products;
• for beans;
• for cereal crops.

And yet, given that pregnancy requires a sufficient amount of vitamins and minerals for your normal development, you should not completely switch to these products. Meat and fish food should also be present in the diet.

If you do not control these indicators, you can lose an unborn child or end up in a hospital for preservation. Last thing - best option developments in the diagnosis of hyperaggregation.

Drug effect on hyperaggregation

It is not necessary to postpone the elimination of the phenomenon of hyperaggregation indefinitely. This can lead to extremely undesirable consequences. Usually, the treatment of such a pathological condition involves a set of measures to eliminate it. They are treated as drug effect assigned even to early stages process, and diet therapy, involving the inclusion in the diet certain products.

With regard to the effects of drugs, drugs that help thin the blood are most often used.

If they are ineffective, prescribe additional therapy in the form of:

• anticoagulant agents;
• novocaine blockade;
• painkillers;
• medicines that dilate blood vessels.

The diet also implies the mandatory inclusion of seafood, herbs, garlic, citrus fruits and ginger in the diet.

Failure to comply with the prescribed measures to influence the regulation of the state of the body can lead to serious consequences and the development of dangerous pathological conditions.

platelets- the smallest blood cells responsible for clotting biological fluid. They take part:

• in stopping bleeding (hemostasis);
• in the nutrition of the walls of blood vessels.

How does platelet aggregation occur?

As soon as we get the slightest cut, the body signals a problem. Platelets rush to the damaged vessels, which begin to stick together together. This action is called aggregation. It takes place in two stages:

1. First, platelets stick together with each other - this is initial stage thrombosis.
2. Then they are attached to the walls of blood vessels.

After that, other elements, even platelets, stick to the platelet clot, and as a result, the thrombus grows until it covers the ruptured walls of the vessels so that the blood does not leak out. However, there is a danger that threatens with increased blood clots - these are heart attacks, strokes.

For any deviations from the norm, contact a specialist.

Blood clotting test

For the study of platelet aggregation, it is necessary to take a blood test:

1. If bruises form from the slightest blows, wounds heal poorly, nosebleeds often come out - this is a signal that blood clotting is reduced.
2. If edema is observed, on the contrary, clotting is increased.

The analysis is carried out by introducing an aggregation inducer and observing the reaction. As an inductor, chemical thrombogenic substances close in composition to natural ones are used.

Platelet aggregation is tested using the following inductors:

• adrenalin;
• constituents vascular wall: adenosine diphosphate (ADP);
• ristocetin (ristomycin);
• collagen;
• serotonin.

Spontaneous platelet aggregation is determined without inductors.

Before taking the test, you need to carefully prepare so that the blood test is accurate. To do this, you must follow these rules:

1. Before passing the analysis, stop taking all aspirin drugs (Dipyridamole, Indomethacin and others) and antidepressants.
2. The analysis is taken on an empty stomach, 12 hours after the last meal, it is especially undesirable to eat fatty foods.
3. Do not overload physically, be calm.
4. Do not drink coffee, alcoholic beverages, do not eat garlic and do not smoke during the day.
5. If in body goes inflammatory process, the delivery of the analysis should be postponed.
6. It is also important to know that during menstruation, women experience a decrease in blood clotting, and this can affect the result of the analysis.

The rate of platelet aggregation

A normal number of platelets in the blood means that a person has a healthy hematopoiesis, tissues and organs are supplied with oxygen and iron in sufficient quantities.

Increased platelet aggregation

To understand what kind of condition it is when platelet aggregation is increased, you need to pay attention to this: the blood is thick, moves slowly through the vessels, and stagnates. This manifests itself in the form of a feeling of numbness, swelling. Such thrombocytosis occurs when:

• widespread atherosclerosis of vessels;
• hypertension;
• diabetes mellitus;
• leukemia;
• stomach or kidney cancer;
• after removal of the spleen;
• sepsis.

Thick blood threatens with such adverse conditions as:

Decreased platelet aggregation

With a small number of platelets in the blood, the vessels become brittle, bleeding stops with difficulty.

If platelet aggregation is reduced, you need:

1. Avoid injury.
2. Use drugs and alcohol with caution.
3. Eat right, avoid spicy and salty foods.
4. There are foods rich in iron (beets, apples, buckwheat, meat, fish, parsley, peppers, nuts, spinach).

Increased aggregation is a marker of hyperaggressive syndrome and thrombophilia. Born's turbidimetric method, based on the registration of changes in the light transmission of platelet-rich plasma, and the method of studying platelet aggregation, based on the analysis of light transmission fluctuations caused by a random change in the number of particles in the optical channel, are most commonly used.

Material for research. Citrated platelet rich plasma

Research method is determined by the order of work on a particular type of aggregometer.

As inductors, solutions of ADP, ristocetin, collagen, adrenaline, and arachidonic acid are most often used. Thrombin, serotonin, etc. solutions can also be used.

Platelet aggregation with ADP

Exposure to small doses of ADP (usually 1*10 -7 mol) leads to the formation of a double wave of aggregation. The first phase (primary wave) depends on the added exogenous ADP, and the second phase (secondary wave of aggregation) occurs due to the release reaction of its own agonists contained in platelet granules. Large doses of ADP (usually 1*10 -5 mol) lead to the fusion of the first and second waves of aggregation.

When analyzing aggregograms, attention is paid to the general nature of aggregation (one-wave, two-wave; complete, incomplete; reversible, irreversible) and the rate of aggregation. The appearance of two-wave aggregation upon stimulation of ADP at concentrations that normally cause reversible aggregation (usually 1-5 μmol) indicates an increase in platelet sensitivity, and the development of single-wave incomplete (and often reversible) aggregation upon stimulation of ADP at concentrations of 10 μmol or more indicates violation of the platelet release reaction.

Platelet aggregation with ristocetin

Determination of platelet aggregation with ristocetin in plasma is used to quantify the von Willebrand factor. The method is based on the ability of ristocetin to stimulate in vitro interaction of von Willebrand factor with platelet glycoprotein Ib. In most cases of von Willebrand disease, ristocetin aggregation is impaired with a normal response to ADP, collagen, and adrenaline. Violation of ristocetin aggregation is also detected in Bernard-Soulier disease. For differentiation, a test with the addition of normal plasma is used: in von Willebrand disease, after the addition of normal plasma, ristocetin aggregation is normalized, while this does not occur in Bernard-Soulier syndrome. Ristocetin-induced platelet agglutination is reduced in most cases of von Willebrand's disease except type IIB.

Platelet aggregation with collagen

Aggregation of platelets with collagen is quite pronounced latent phase, during which phospholipase C is activated. Depending on the concentration of the reagent used, the duration of this phase can be 5-7 minutes. After the completion of this period, processes occur in platelets leading to the formation of secondary messengers, as a result of which the secretion of platelet granules and the synthesis of thromboxane A2 develop, which is accompanied by a sharp increase in interplatelet interaction.

In laboratory and clinical practice, collagen is most often used at a final concentration of 50 μg/ml, however, collagens from different companies may have different activities, which must be taken into account when using them.

Platelet aggregation with adrenaline

Adrenaline, upon contact with platelets, interacts with α2-adrenergic receptors, which causes inhibition of adenylate cyclase. It is possible that the mechanism underlying the implementation of the effect of adrenaline and the development of the first wave of aggregation does not depend on the formation of thromboxane A2, the release reaction or synthesis of platelet aggregation factor, but is associated with the ability of adrenaline to directly change the permeability of the cell membrane for calcium ions. The second wave of aggregation occurs as a result of the release reaction and production of thromboxane A2.

Platelet aggregation with arachidonic acid

Arachidonic acid is a natural aggregation agonist, and its action is mediated by the effects of prostaglandins G2 and H2, thromboxane A2, and includes the activation of both phospholipase C with subsequent formation of secondary messengers, mobilization of intracellular calcium and expansion of the cell activation process, and phospholipase A2, which directly leads to release of endogenous arachidonic acid. Aggregation of platelets with arachidonic acid occurs quite quickly, so the curve characterizing this process is more often of a single-wave character.

To induce platelet aggregation, arachidonic acid is used at concentrations of 10 -3 -10 -4 mol. When working with arachidonic acid, it should be borne in mind that this substance oxidizes very quickly in air.

A test for aggregation with arachidonic acid is recommended in cases of using drugs that affect the aggregation reaction (for example, acetylsalicylic acid, penicillin, indomethacin, delagil, diuretics), which must be taken into account when evaluating the results of studies.

A specific stimulated process during which gluing occurs, or rather, aggregation of platelets, is called aggregation. It takes place in two stages. In the first stage, platelets stick together, in the second they are attached to the walls of blood vessels. Thus, these cells form a kind of plug. In medicine, it is called a thrombus.

With the help of this reaction, it is possible to determine violations in the work of the cardiovascular system. A blood test, which is taken to study platelets, is prescribed in cases of: reduced / increased clotting (in the first case, this is evidenced by bruises from minor blows, poor wound healing, etc., in the second - swelling), pregnancy with some complications.

Why does the human body need platelet aggregation?

This reaction is protective. At various injuries blood vessels, platelets stick together, reach the diameter of the blood flow and block the problem area. Deviation from the norm of indicators of aggregation requires immediate intervention doctors. Increased platelet adhesion can lead to a heart attack as well as a stroke. Reduced aggregation says that a minor cut will result in a large loss of blood, subsequently provoke anemia, exhaustion, and so on.

Platelet aggregation, the norm of which is 0-20%, is very important for normal functioning organism.

Procedure for taking a blood clotting test

Before the analysis, the attending physician should conduct a specialized consultation with the patient. During the conversation, he must indicate: the purpose of blood donation, what clotting means, the dependence of treatment on the test result, how, when, under what circumstances the procedure will take place. Also, at the consultation, the doctor is obliged to talk about the possibility of discomfort for the patient during the test. Platelet aggregation is examined after the patient has followed a diet compiled by a specialist for 1-3 days, and 8 hours before the procedure, he refused foods that contain a lot of fat. Also, for the reliability of the results, the patient is forced to refrain from taking medication for some time. If this is not possible, then this should be taken into account when examining blood for clotting.

Platelet aggregation during pregnancy

During this period, for women, there is some likelihood of increased blood clotting. This deviation from the norm occurs in the pathology of pregnancy. Platelet aggregation in women in an “interesting” position should be constantly monitored by a hematologist, who gives direction for the necessary tests.

In the case of an increase, in some cases a decrease in blood clotting, a specialist prescribes medication. Doctors strongly recommend checking platelet aggregation at the planning stage of pregnancy, as this can help avoid significant health problems for the mother and child in the future.

Deviations from the norm. What to do?

If blood clotting is reduced or increased, in any case, you need to consult an experienced specialist. He will make a surrender additional tests will conduct a survey, examination and diagnosis. Often, platelet aggregation that does not correspond to the norm is secondary. It should also be borne in mind that in women, a decrease in blood clotting during menstruation is possible. This protects them for a while from the occurrence of blood clots. Fatal outcome may be with an increased tendency to blood clotting, therefore, at the slightest suspicion of this (numbness of the limbs, swelling), immediate treatment is necessary. Ignoring symptoms is life threatening.

What can affect the result of a blood test on clotting?

If the patient did not take into account the recommendations of the attending physician before taking the test, this may lead to incorrect treatment. Eventually general condition the patient will suffer irreparable harm. The distortion of the results of the analysis for platelet aggregation may be due to the fault of the laboratory assistant who performed it. This happens with the wrong choice of inductors that stimulate required process or when compound reactions do not interact well with each other. Impaired platelet aggregation occurs in people who are obese, hemolytic, and tobacco smokers.