Increased breakdown of red blood cells causes. Hemolysis of red blood cells

Topic: “HAEMOSTASIS AND BLOOD GROUPS.”

Lecture No. 4.

Plan:

1. Hemolysis and its types.

2. Erythrocyte sedimentation rate and its determination.

3. Hemostasis and its mechanisms.

4. Blood groups.

5. Rh factor.

GOAL: Know physiological mechanisms hemolysis, erythrocyte sedimentation rate, hemostasis (vascular-platelet and coagulation).

Be able to distinguish between blood groups, understand the essence of Rh conflict.

This knowledge and skills are necessary in the clinic to monitor the course of the disease and recovery, when stopping bleeding, transfusion of donor blood, and carrying out measures to prevent miscarriage during repeat pregnancy in Rh-negative women.

Hemolysis(Greek haima - blood, lusis - decay, dissolution), or hematolysis, erythrolysis, is the process of intravascular breakdown of red blood cells and the release of hemoglobin into the blood plasma, which turns red and becomes transparent ("varnish blood") .

1) Osmotic hemolysis occurs when osmotic pressure decreases, which first leads to swelling and then destruction of red blood cells. A measure of the osmotic stability (resistance) of erythrocytes is the MaCl concentration at which hemolysis begins. In humans, this occurs in a 0.4% solution, and in a 0.34% solution all red blood cells are destroyed. In some diseases, the osmotic stability of erythrocytes decreases, and hemolysis can occur at high concentrations of NaCl in plasma.

2) Chemical hemolysis occurs under the influence chemical substances, destroying the protein-lipid membrane of erythrocytes (ether, chloroform, alcohol, benzene, bile acids, etc.).

3) Mechanical hemolysis is observed under strong mechanical influences on the blood, for example, when transporting ampoule blood on a bad road, vigorously shaking the ampoule with blood, etc.

4) Thermal hemolysis occurs when ampoule blood is frozen and thawed, as well as when it is heated to a temperature of 65-68°C.

5) Biological hemolysis develops when transfusion of incompatible or poor quality blood, from the bites of poisonous snakes, scorpions, under the influence of immune hemolysins, etc.

6) In-hardware hemolysis can occur in the heart-lung machine during blood perfusion (pumping).

Erythrocyte sedimentation rate (reaction)(abbreviated ESR, or ROE) is an indicator reflecting changes in the physicochemical properties of blood and the measured value of the plasma column released from red blood cells when they settle from a citrate mixture (5% sodium citrate solution) for 1 hour in a special pipette of the T.P. device. Panchenkova.

IN normal ESR is equal to:

for men - 1-10 mm/hour;

for women - 2-15 mm/hour;

in newborns - 0.5 mm/hour;

in pregnant women before childbirth - 40-50 mm/hour.

An increase in ESR greater than the specified values ​​is, as a rule, a sign of pathology. The value of ESR depends on the properties of plasma, primarily on the content of large molecular proteins in it - globulins and especially fibrinogen. The concentration of these proteins increases during all inflammatory processes. During pregnancy, the fibrinogen content before childbirth is almost 2 times higher than normal, and ESR reaches 40-50 mm/hour. The influence of plasma properties on the ESR value is indicated by the experimental results. (For example, male red blood cells placed in male blood plasma settle at a rate of 5-9 mm/hour, and in the plasma of a pregnant woman - up to 50 mm/hour. Likewise, female red blood cells settle in male blood plasma at a rate of about 9 mm /hour, and in the plasma of a pregnant woman - up to 60 mm/hour. It is believed that large molecular proteins (globulins, fibrinogen) reduce the electrical charge of blood cells and the phenomenon of electrical repulsion, which contributes to a higher ESR (the formation of longer coin columns from red blood cells). with an ESR of 1 mm/hour, coin columns are formed from approximately 11 erythrocytes, and with an ESR of 75 mm/hour, clusters of erythrocytes have a diameter of 100 μm or more and consist of a large number (up to 60,000) of erythrocytes.)

To determine ESR, a T.P. Panchenkov device is used, consisting of a stand and graduated glass pipettes (capillaries).

Hemostasis(Greek haime - blood, stasis - motionless state) - this is a stop in the movement of blood through a blood vessel, i.e. stop bleeding. There are 2 mechanisms to stop bleeding:

1) vascular-platelet (microcirculatory) hemostasis;

2) coagulation hemostasis (blood clotting).

The first mechanism is capable of independently stopping bleeding from the most frequently injured small vessels in a few minutes with a fairly low blood pressure. It consists of two processes:

1) vascular spasm,

2) formation, compaction and contraction of the platelet plug.

The second mechanism for stopping bleeding is blood clotting (hemocoagulation) ensures cessation of blood loss in case of damage to large vessels, mainly muscular type. It is carried out in three phases: Phase I - formation of prothrombinase;

Phase II - thrombin formation;

Phase III - conversion of fibrinogen to fibrin.

In the blood coagulation mechanism, in addition to the wall blood vessels And shaped elements, 15 plasma factors are involved: fibrinogen, prothrombin, tissue thromboplastin, calcium, proaccelerin, convertin, antihemophilic globulins A and B, fibrin-stabilizing factor, etc. Most of these factors are formed in the liver with the participation of vitamin K and are proenzymes related to the globulin fraction of proteins plasma. Trigger Blood clotting is caused by the release of thromboplastin by damaged tissue and disintegrating platelets. Calcium ions are required to carry out all phases of the coagulation process.

A network of insoluble fibrin fibers and the red blood cells, leukocytes and platelets entangled in it form a blood clot.

Blood plasma devoid of fibrinogen and some other substances involved in coagulation is called serum. And blood from which fibrin has been removed is called defibrinated.

The normal time for complete coagulation of capillary blood is 3-5 minutes, for venous blood - 5-10 minutes.

In addition to the coagulation system, the body simultaneously has two more systems: anticoagulant and fibrinolytic.

Anticoagulant system interferes with the processes of intravascular coagulation or slows down hemocoagulation. The main anticoagulant of this system is heparin, secreted from lung and liver tissue and produced by basophilic leukocytes and tissue basophils ( mast cells connective tissue). Heparin inhibits all phases of the blood coagulation process, suppresses the activity of many plasma factors and the dynamic transformations of platelets.

Allocable salivary glands medicinal leeches hirudin acts depressingly on the third stage of the blood coagulation process, i.e. prevents the formation of fibrin.

Fibrinolytic the system is capable of dissolving formed fibrin and blood clots and is the antipode of the coagulation system. Main function fibrinolysis- splitting fibrin and restoring the lumen of a vessel clogged with a clot. Disruption of the functional relationships between the coagulation, anticoagulation and fibrinolytic systems can lead to serious diseases: increased bleeding, intravascular thrombus formation and even embolism.

Blood groups- a set of characteristics characterizing the antigenic structure of erythrocytes and the specificity of anti-erythrocyte antibodies, which are taken into account when selecting blood for transfusions (Latin transfusio - transfusion).

In 1901, the Austrian K. Landsteiner and in 1903 the Czech J. Jansky discovered that when mixing blood different people erythrocytes sticking to each other is often observed - a phenomenon agglutination(Latin agglutinatio - gluing) followed by their destruction (hemolysis). It was found that erythrocytes contain agglutinogens A and B, adhesive substances of glycolipid structure, antigens. Found in plasma agglutinins a and b, modified proteins of the globulin fraction, antibodies that glue erythrocytes. Agglutinogens A and B in erythrocytes, like agglutinins a and b in plasma, may be present one at a time, together, or absent in different people. Agglutinogen A and agglutinin a, as well as B and b are called the same name. The adhesion of red blood cells occurs when the red blood cells of the donor (the person giving blood) meet the same agglutinins of the recipient (the person receiving blood), i.e. A + a, B + b or AB + ab. From this it is clear that in the blood of every person there are opposite agglutinogen and agglutinin.

According to the classification of J. Jansky and K. Landsteiner, people have 4 combinations of agglutinogens and agglutinins, which are designated as follows:

People of group I can only receive blood transfusions from this group. Group I blood can be transfused to people of all groups. Therefore, people with blood type I are called universal donors. People with group IV can be transfused with blood of all groups, so these people are called universal recipients. Group IV blood can be transfused to people with group IV blood. The blood of people of groups II and III can be transfused to people with the same, as well as with IV blood group.

However, currently in clinical practice only blood of the same group is transfused, and in small quantities (no more than 500 ml), or the missing blood components are transfused (component therapy). This is due to the fact that:

firstly, with large massive transfusions, dilution of the donor’s agglutinins does not occur, and they glue the recipient’s red blood cells together;

secondly, with a careful study of people with blood type I, immune agglutinins anti-A and anti-B were discovered (in 10-20% of people); transfusion of such blood to people with other blood groups causes serious complications. Therefore, people with blood type I, containing anti-A and anti-B agglutinins, are now called dangerous universal donors;

thirdly, many variants of each agglutinogen have been identified in the ABO system. Thus, agglutinogen A exists in more than 10 variants

In 1930, K. Landsteiner, speaking at the award ceremony Nobel Prize for the discovery of blood groups, suggested that in the future new agglutinogens will be discovered, and the number of blood groups will grow until it reaches the number of people living on earth. This scientist’s assumption turned out to be correct. To date, more than 500 different agglutinogens have been discovered in human erythrocytes.

To determine blood groups, you need to have standard sera containing known agglutinins, or anti-A and anti-B coliclones containing diagnostic monoclonal antibodies. If you mix a drop of blood from a person whose group needs to be determined with serum of groups I, II, III or with anti-A and anti-B coliclones, then by the agglutination that occurs, his group can be determined.

Transfused blood always has a multilateral effect. In clinical practice there are:

1) replacement effect - replacement of lost blood;

2) immunostimulating effect - to stimulate the defenses;

3) hemostatic (hemostatic) effect - to stop bleeding, especially internal;

4) neutralizing (detoxification) effect - in order to reduce intoxication;

5) nutritional effect - introduction of proteins, fats, carbohydrates in an easily digestible form.

As we just noted! In addition to the main agglutinogens A and B, erythrocytes may contain other additional ones, in particular, the so-called Rh agglutinogen (Rh factor). It was first found in 1940 by K. Landsteiner and I. Wiener in the blood of a rhesus monkey. 85% of people have the same Rh agglutinogen in their blood. This blood is called Rh positive. Blood that lacks Rh agglutinogen is called Rh negative (in 15% of people). The Rh system has more than 40 varieties of agglutin genes - D, C, E, of which D is the most active . A special feature of the Rh factor is that people do not have anti-Rhesus agglutinins. However, if a person with Rh-negative blood is repeatedly transfused with Rh-positive blood, then under the influence of the administered Rh agglutinogen, specific anti-Rh agglutinins and hemolysins are produced in the blood. In this case, transfusion of Rh-positive blood to this person can cause agglutination and hemolysis of red blood cells - transfusion shock will occur.

The Rh factor is inherited and is of particular importance for the course of pregnancy. For example, if the mother does not have the Rh factor, but the father has it (the probability of such a marriage is 50%), then the fetus may inherit the Rh factor from the father and turn out to be Rh positive. The fetal blood enters the mother's body, causing the formation of anti-Rhesus agglutinins in her blood. If these antibodies cross the placenta back into the fetal blood, agglutination will occur. With a high concentration of anti-Rhesus agglutinins, fetal death and miscarriage may occur. In mild forms of Rh incompatibility, the fetus is born alive, but with hemolytic jaundice.

Rh conflict occurs only with a high concentration of anti-Rhesus agglutinins. Most often, the first child is born normal, since the titer of these antibodies in the mother’s blood increases relatively slowly (over several months). But when a Rh-negative woman becomes pregnant again with a Rh-positive fetus, the threat of Rh-conflict increases due to the formation of new portions of anti-Rhesus agglutinins. Rh incompatibility during pregnancy is not very common: approximately one case in 700 births.

To prevent Rh-conflict, pregnant Rh-negative women are prescribed anti-Rh-gammaglobulin, which neutralizes Rh-positive fetal antigens.

Hemolysis is the process of destruction of the membranes of red blood cells - erythrocytes, with further release of hemoglobin into the plasma. provoked by the release of a substance - hemolysin. The membranes of red blood cells are destroyed under the influence of specific toxins of a bacterial nature or produced by enzymes.

Kinds

The class and types of hemolysis depend on the location of the processes and on the reasons that contributed to the disintegration of the erythrocyte membranes:

• Natural hemolysis. The breakdown of red blood cells is an absolutely normal physiological process that occurs in the human body. The life cycle of red blood cells ranges from 100 to 130 days. After which the cells are destroyed and new ones are formed in their place.
• Chemical hemolysis is the process of destruction of cells due to exposure to them toxic substances, leading to rupture of their membrane (alkali, ether, alcohol, chloroform).
• Biological hemolysis - occurs due to the penetration of hemolytic poison into the human blood through an insect bite. It can also develop with incompatible.
• Temperature hemolysis - under the influence low temperatures on red cells, ice crystals form inside them, tearing the cell from the inside.
• Mechanical class – hemolysis in vitro. If you shake a flask of blood, the process of destruction of red blood cells will begin.
• Osmotic hemolysis. The ability of blood cells to be destroyed under the influence of external and internal factors is used when taking tests to detect anemia. When red cells enter an environment with increased osmotic pressure, they break.

Causes

The reasons that trigger the process of destruction of hemolysis can be either external (damage to cells during or transportation of material) or internal (takes place inside the red blood cell itself).

Internal factors of cell damage include a number of diseases:

• Hemolytic type anemia.
• Hemoglobinuria.
• Aglutinin disease (cold disease).
• Penetration of poisons.

During internal damage red cells are destroyed in the liver, spleen and bone marrow. This occurs due to the development of microspherocytosis congenital form, and autoimmune nature, .

Considering a number of factors that destroy the membranes of red blood cells, it becomes clear that hemolysis poses a danger to the entire body, as it often causes an enlargement of the spleen and liver, leading to the development of very serious diseases.

During pregnancy, the destruction of the walls of red blood cells is due to the presence. In this case, hemolysis during pregnancy is not a severe pathology, but only a physiological process. To normalize a woman’s condition, it is necessary to compensate for the lack of iron in the body. To do this, just stick to and use pomegranates regularly.

Symptoms

The main symptoms of the process of destruction of red blood cells, which patients primarily note:

• Yellowing skin.
• In some cases, pale skin is noted.
• Cardiopalmus.
• Delamination of the nail plate.
• Poor hair condition.

It also happens that a person does not even suspect that he has such severe pathological processes as hemolysis in his body. The presence of blood hemolysis is detected during donation.

During an exacerbation, the patient experiences following signs hemolysis:

• Frequent nausea.
• Vomit.
• Dizziness.
• Regular feeling of excessive fatigue.
• Increased body temperature.

The process of breakdown of red blood cells in many cases leads to the development of anemia, quite dangerous disease, which, in turn, can lead to the formation of stones in the bile ducts (cholelithiasis).

Consequences

What are the consequences of hemolysis and should I worry? In many patients, when pathology is detected, a psychosomatic illness begins to form. They find signs of non-existent diseases in themselves only because they know what is happening inside their body.

Decoding

As a rule, if hemolysis is detected as a result, a repeat blood donation is prescribed. This is explained by the fact that they could be destroyed under the influence of a mechanical factor - due to careless work with the test tube material.

Damage to blood cells may be caused by the nurse pushing the blood too quickly or by using a needle that is too thin during the test.

Damage to red cells is often observed when the material is incorrectly transferred from a test tube into a special flask. Breaking against the glass walls, red blood cells stain the plasma pink, which makes it impossible to separate it in a centrifuge. Such cases of red blood cell damage are called partial hemolysis. This phenomenon is not a disease, but only an error in collecting material and incorrect analysis.

Before repeating hemolysis, the patient needs to drink a small amount of plain water. If a repeated analysis again shows the presence of destroyed red blood cells, a diagnosis of acute hemolysis is made.

Spicy

This is a very serious pathological process, acute hemolysis can lead to serious consequences.

If the patient is conscious at the time the disease is diagnosed, he may complain of a number of symptoms of acute hemolysis:

• Pain in the thoracic region.
• Pain in the stomach.
• Excessive stimulation of the central nervous system.
• Internal heat.
• Pain in the lumbar region.

The cause of acute hemolysis of blood is the erroneous infusion of incorrectly selected donor blood and the alienation of its red blood cells by the recipient’s body.

With the development of acute hemolysis, during surgery using general anesthesia, symptoms pathological process will be sharp, and if there is a catheter with a urinal, it will be visible that the urine has become red. Sometimes black urine is discharged.

Diagnostics

In order to confirm the presence of a pathological process of destruction of red blood cells in the body, it is necessary to analyze the patient’s blood and urine. With hemolysis, the processes of bilirubinemia, fibrinolysis, hemoglobinemia, and reduced coagulant potential will be identified. The presence of hyperkalemia and hemoglobinuria is noted in the urine. As red blood cells break down, the patient's daily urine output decreases, and in some cases, urine may be completely absent.

Treatment

The uncontrolled destruction of red blood cells must be treated immediately. If the cause of the pathology is an error during blood transfusion, therapeutic methods are used aimed at stopping the infusion of red blood cells from incompatible blood.

To prevent the occurrence of hyperfusion in the kidneys and hypovolemia, special solutions are administered. A procedure is carried out with intravenous administration of Heparin. The procedure is aimed at removing free hemoglobin from the blood. Prednisolone is also used in the treatment of acute hemolysis.

Drug treatment acute hemolysis is prescribed by the attending physician, based on the clinical picture and symptoms of each individual case. It is important to know exactly when the pathological process began to develop in the patient’s body.

In particular severe cases for treatment it is necessary to urgently prescribe hemodialysis, especially if there is renal failure.

One of the reasons for the rapid destruction of red blood cells is long-term use certain medications. These are mainly anti-tuberculosis drugs, drugs from the sulfonamide group and hypoglycemic antibiotics.

With this clinical picture, hemolysis of the destruction of blood cells is not a pathology, and does not indicate the presence of serious diseases - it is just a natural reaction of the body to taking certain medications, the patient’s condition normalizes after completing the course of taking them.

Hemolysis of red blood cells, or destruction, occurs constantly in the body, and completes their life cycle, which lasts 4 months. The process by which this happens as planned goes unnoticed by humans. But if the destruction of oxygen carriers is carried out under the influence of external or internal factors, hemolysis becomes hazardous to health. To prevent it, it is important to follow preventive measures, and to successful treatment– quickly recognize characteristic symptoms and find out the reasons why the pathology develops.

Hemolysis of red blood cells is their damage, in which hemoglobin is released into the blood plasma, and the blood itself becomes transparent and acquires a red color, like a dissolved dye in distilled water, and is called “lacquer blood.”

The process occurs under the influence of a substance - hemolysin, in the form of an antibody or bacterial toxin. Red blood cells survive destruction in the following way:

1. Under the influence of a stimulus, the red blood cell grows in size.
2. The cell membrane is not capable of stretching, since this ability is not inherent to it.
3. Rupture of the membrane of an erythrocyte, in which its contents enter the blood plasma.

The video shows the process clearly

Features and shapes

Hemolysis of erythrocytes occurs against the background of impaired hemoglobin production, excess erythromycin blood cells, physiological jaundice, genetic inferiority of red blood cells, in which they are prone to destruction, as well as autoimmune disorders, when antibodies show aggression towards own cells blood. This happens when acute leukemia, myeloma and systemic lupus erythematosus.