AVO system
The doctrine of blood groups arose from the needs clinical medicine. When transfusing blood from animals to humans or from humans to humans, doctors often observed severe complications, sometimes ending in the death of the recipient (the person receiving the blood transfusion).
With the discovery of blood groups by the Viennese doctor K. Landsteiner (1901), it became clear why in some cases blood transfusions are successful, while in others they end tragically for the patient. K. Landsteiner first discovered that the plasma, or serum, of some people is able to agglutinate (stick together) the red blood cells of other people. This phenomenon has been named isohemagglutination. It is based on the presence of antigens in erythrocytes, called agglutinogens and denoted by the letters A and B, and in plasma - natural antibodies, or agglutinins, called α and β . Agglutination of erythrocytes is observed only if agglutinogen and agglutinin of the same name are found: A and α , In and β.
It has been established that agglutinins, being natural antibodies (AT), have two binding centers, and therefore one molecule of agglutinin is able to form a bridge between two erythrocytes. In this case, each of the erythrocytes, with the participation of agglutinins, can contact the neighboring one, due to which a conglomerate (agglutinate) of erythrocytes arises.
In the blood of the same person, there cannot be agglutinogens and agglutinins of the same name, since otherwise mass agglutination of erythrocytes would occur, which is incompatible with life. Only four combinations are possible in which agglutinogens and agglutinins of the same name do not occur, or four blood groups: I- αβ, II- Aβ, III-B α ,IV-AB.
In addition to agglutinins, plasma or serum contains hemolysins: there are also two types of them and they are designated, like agglutinins, by the letters α and β . When the agglutinogen and hemolysin of the same name meet, hemolysis of erythrocytes occurs. The action of hemolysins is manifested at a temperature of 37-40 ο WITH. That is why, when transfusing incompatible blood in a person, already after 30-40 s. erythrocyte hemolysis occurs. At room temperature if agglutinogens and agglutinins of the same name occur, agglutination occurs, but hemolysis is not observed.
In the plasma of people with II, III, IV blood groups, there are antiagglutinogens that have left the erythrocyte and tissues. They are designated, like agglutinogens, by the letters A and B (Table 6.4).
Table 6.4. Serological composition of the main blood groups (ABO system)
| Serum group | group of erythrocytes | |||
| I(O) | II(A) | III(V) | IV (AB) | |
| Iαβ | - | + | + | + |
| II β | - | - | + | + |
| IIIα | - | + | - | + |
| IV | - | - | - | - |
As can be seen from the table below, the I blood group does not have agglutinogens, and therefore, according to international classification designated as group 0, II- bears the name A, III-B, IV-AB.
To resolve the issue of compatibility of blood groups, the following rule is used: the environment of the recipient must be suitable for the life of the erythrocytes of the donor (the person who donates blood). Plasma is such a medium, therefore, the recipient should take into account the agglutinins and hemolysins in the plasma, and the donor should take into account the agglutinogens contained in the erythrocytes.
Blood transfusion rules
Indications for transfusion of any transfusion medium, as well as its dosage and choice of transfusion method, are determined by the attending physician based on clinical and laboratory data. The doctor performing the transfusion is obliged, regardless of previous studies and available records, to personally conduct the following control studies:
1) determine the recipient's blood group according to the AB0 system and compare the result with the data of the medical history;
2) determine the group affiliation of the donor's erythrocytes and compare the result with the data on the label of the container or bottle;
3) conduct tests for compatibility in relation to blood groups of the donor and recipient according to the AB0 system and the Rh factor;
4) conduct a biological test.
Transfusion is prohibited donated blood and its components not tested for AIDS, hepatitis B surface antigen and syphilis. Transfusion of blood and its components is carried out in compliance with the rules of asepsis using disposable plastic systems. Blood received from a donor (usually in a volume of 450 ml) after adding a preservative solution can be stored in a refrigerator at a temperature of 4-8°C for no more than 21 days. Frozen at temperature liquid nitrogen(-196°C), erythrocytes can be stored for years.
It is allowed to transfuse whole blood and its components only of the group and Rh affiliation that the recipient has. In exceptional cases, it is allowed to transfuse Rh-negative blood of group O (I) (“universal donor”) to a recipient with any blood type in an amount up to 500 ml (except for children). The blood of Rh-negative donors A (II) or B (III) can be transfused not only to recipients matching the group, but also to a recipient with an AB (IV) group, regardless of his Rh affiliation. A patient with AB (IV) group Rh-positive blood can be considered a "universal recipient".
In addition, in the absence of single-group blood, blood (erythrocyte mass) of the 0 (I) Rh-positive group can be transfused to a Rh-positive recipient of any group according to the AB0 system. Blood group A (II) or B (III) Rh-positive can be transfused to a Rh-positive recipient with group AB (IV). In all cases, a compatibility test is absolutely mandatory. In the presence of antibodies of rare specificity, an individual selection of donor blood and additional tests for compatibility are required.
After transfusion of incompatible blood, the following complications may occur: hemotransfusion shock, dysfunction of the kidneys and liver, metabolic processes, activity of the gastrointestinal tract, cardiovascular and central nervous systems, respiration, hematopoiesis. Organ dysfunction occurs as a result of acute intravascular hemolysis (erythrocyte breakdown). As a rule, as a result of these complications, anemia develops, which can last up to 2-3 months or more. If the established rules for blood transfusion are violated or indications are unclear, non-hemolytic post-transfusion reactions may also occur: pyrogenic, antigenic, allergic and anaphylactic. All post-transfusion complications require immediate treatment.
11. Rh antigenic system of the blood. Definition method. Types of Rh immunization and their mechanisms.
6.3.2. Rhesus system (Rh-hr) and others
K. Landsteiner and A. Wiener (1940) found in the erythrocytes of the macaque monkey Rhesus AG, which they called Rh factor. Later it turned out that approximately 85% of people of the white race also have this hypertension. Such people are called Rh-positive (Rh +). About 15% of people do not have this hypertension and are called Rh-negative (Rh).
It is known that the Rh factor is a complex system that includes more than 40 antigens, denoted by numbers, letters and symbols. The most common types of Rh antigens are D (85%), C (70%), E (30%), e (80%) - they also have the most pronounced antigenicity. The Rh system does not normally have agglutinins of the same name, but they can appear if an Rh-negative person is transfused with Rh-positive blood.
The Rh factor is inherited. If a woman is Rh, a man is Rh +, then the fetus will inherit the Rh factor from the father in 50-100% of cases, and then the mother and fetus will be incompatible with the Rh factor. It has been established that during such a pregnancy, the placenta has an increased permeability to fetal erythrocytes. The latter, penetrating into the mother's blood, lead to the formation of antibodies (anti-Rhesus agglutinins). Penetrating into the blood of the fetus, antibodies cause agglutination and hemolysis of its erythrocytes.
The most severe complications arising from transfusion of incompatible blood and Rh conflict are caused not only by the formation of erythrocyte conglomerates and their hemolysis, but also by intense intravascular coagulation, since erythrocytes contain a set of factors that cause platelet aggregation and the formation of fibrin clots. In this case, all organs suffer, but the kidneys are especially severely damaged, since clots clog the "wonderful network" of the kidney glomerulus, preventing the formation of urine, which may be incompatible with life.
According to modern ideas, the erythrocyte membrane is considered as a set of the most diverse AGs, of which there are more than 500. Only from these AGs can more than 400 million combinations, or group signs of blood, be made. If we take into account all the other AGs found in the blood, then the number of combinations will reach 700 billion, i.e., much more than people on the globe. Of course, not all AHs are important for clinical practice. However, when transfusing blood with relatively rare hypertension, severe blood transfusion complications and even death of the patient can occur.
Often occurs during pregnancy serious complications, including severe anemia, which can be explained by the incompatibility of blood groups according to the systems of poorly studied maternal and fetal antigens. At the same time, not only the pregnant woman suffers, but also future child. Blood type incompatibility between mother and fetus can cause miscarriages and premature births.
Hematologists identify the most important antigenic systems: ABO, Rh, MNSs, P, Lutheran (Lu), Kell-Kellano (Kk), Lewis (Le), Duffy (Fy) and Kid (Jk). These antigen systems are used in forensic science to establish paternity and sometimes in organ and tissue transplants.
Currently, whole blood transfusion is relatively rare, since they use transfusion of various blood components, that is, they transfuse what the body needs most: plasma or serum, erythrocyte, leukocyte or platelet mass. In this situation, fewer antigens are administered, which reduces the risk of post-transfusion complications.
Hemagglutination reaction - one of the main methods by which erythrocyte antigens are determined. RBC agglutination is mediated by antibodies. The speed and severity of this process depend on the number of erythrocytes, the concentration of antibodies, pH, temperature and ionic strength of the solution. Agglutination occurs when the binding forces exceed the repulsive forces due to the negative charge on the erythrocyte cell surface. IgMs carrying 10 binding sites cause erythrocyte agglutination even in saline. IgG cannot cause agglutination until the negative charge of erythrocytes is reduced with the help of some macromolecular substance (for example, bovine albumin) or removal of sialic acids (for this, erythrocytes are treated with proteases: ficin, papain, bromelain or trypsin).
Agglutination also depends on the availability, i.e., the number and location of antigen molecules on the surface of the erythrocyte. Antigens of the AB0 system (erythrocyte antigens A and B) are located on outer surface cell membrane and therefore easily bind to antibodies, and antigens of the Rh system - in its thickness. The availability of such antigens is enhanced by the treatment of erythrocytes with enzymes.
8. Transfusion of correctors of plasma coagulation hemostasis
Plasma is the liquid part of the blood, devoid of cellular elements. Normal plasma volume is about 4% of total body weight (40-45 ml/kg). Plasma components maintain normal circulating blood volume and fluidity. Plasma proteins determine its colloid-oncotic pressure and balance with hydrostatic pressure; they also support the systems of blood coagulation and fibrinolysis in an equilibrium state. In addition, plasma ensures the balance of electrolytes and the acid-base balance of the blood.
In medical practice, fresh frozen plasma, native plasma, cryoprecipitate and plasma preparations are used: albumin, gamma globulins, blood coagulation factors, physiological anticoagulants (antithrombin III, protein C and S), components of the fibrinolytic system.
8.1. Characteristics of correctors for plasma coagulation hemostasis
Fresh-frozen plasma is understood to mean plasma separated from erythrocytes by centrifugation or apheresis within 4-6 hours after blood exfusion and placed in a low-temperature refrigerator that provides complete freezing to a temperature of -30°C per hour. This mode of plasma preparation ensures its long-term (up to a year) storage. In fresh frozen plasma, labile (V and VIII) and stable (I, II, VII, IX) coagulation factors are preserved in the optimal ratio.
If cryoprecipitate is removed from the plasma during fractionation, then the remaining part of the plasma is the supernatant plasma fraction (cryosupernatant), which has its own indications for use.
After separation from the plasma of water, the concentration in it total protein, plasma coagulation factors in particular, IX, increases significantly - such plasma is called "native concentrated plasma".
The transfused fresh frozen plasma must be of the same group as the recipient according to the AB0 system. Rh compatibility is not mandatory, since fresh frozen plasma is a cell-free medium, however, with volumetric transfusions of fresh frozen plasma (more than 1 liter), Rh compatibility is mandatory. Compatibility for minor erythrocyte antigens is not required.
It is desirable that fresh frozen plasma meet the following standard quality criteria: protein content of at least 60 g/l, hemoglobin content of less than 0.05 g/l, potassium level of less than 5 mmol/l. The level of transaminases should be within the normal range. The results of tests for markers of syphilis, hepatitis B and C, HIV are negative.
Once thawed, plasma should be used within one hour and should not be re-frozen. V emergency cases in the absence of single group fresh frozen plasma, transfusion of plasma of group AB (IV) to a recipient with any blood group is allowed.
The volume of fresh frozen plasma obtained by centrifugation from a single dose of blood is 200-250 ml. When conducting double donor plasmapheresis, the plasma output can be 400-500 ml, hardware plasmapheresis - no more than 600 ml.
8.2. Indications and contraindications for transfusion of fresh frozen plasma
Indications for the appointment of fresh frozen plasma transfusions are:
- acute syndrome of disseminated intravascular coagulation (DIC), complicating the course of shocks of various origins (septic, hemorrhagic, hemolytic) or caused by other causes (amniotic fluid embolism, crush syndrome, severe injuries with crushing of tissues, extensive surgical operations, especially on the lungs, blood vessels, brain, prostate), massive transfusion syndrome;
- acute massive blood loss (more than 30% of the circulating blood volume) with the development hemorrhagic shock and DIC;
- liver diseases accompanied by a decrease in the production of plasma coagulation factors and, accordingly, their deficiency in circulation (acute fulminant hepatitis, cirrhosis of the liver);
- overdose of anticoagulants of indirect action (dicumarin and others);
- when performing therapeutic plasmapheresis in patients with thrombotic thrombocytopenic purpura (Moshkowitz's disease), severe poisoning, sepsis, acute DIC;
- coagulopathy due to deficiency of plasma physiological anticoagulants.
It is not recommended to transfuse fresh frozen plasma for the purpose of replenishing the circulating blood volume (there are safer and more economical means for this) or for the purposes of parenteral nutrition. With caution, transfusion of fresh frozen plasma should be prescribed in individuals with a burdened transfusion history, in the presence of congestive heart failure.
8.3. Features of transfusion of fresh frozen plasma
Transfusion of fresh frozen plasma is carried out through a standard blood transfusion system with a filter, depending on clinical indications- jet or drip, in acute DIC with severe hemorrhagic syndrome- jet. It is forbidden to transfuse fresh frozen plasma to several patients from one container or bottle.
When transfusing fresh frozen plasma, it is necessary to perform a biological test (similar to the transfusion of blood gas carriers). The first few minutes after the start of fresh frozen plasma infusion, when a small amount of transfused volume has entered the recipient's circulation, are decisive for the occurrence of possible anaphylactic, allergic and other reactions.
The volume of transfused fresh frozen plasma depends on the clinical indications. In case of bleeding associated with DIC, the administration of at least 1000 ml of fresh frozen plasma at once is indicated under the control of hemodynamic parameters and central venous pressure. It is often necessary to re-introduce the same volumes of fresh frozen plasma under the dynamic control of the coagulogram and the clinical picture. In this state, the introduction of small amounts (300-400 ml) of plasma is ineffective.
In case of acute massive blood loss (more than 30% of the volume of circulating blood, for adults - more than 1500 ml), accompanied by the development of acute DIC, the amount of transfused fresh frozen plasma should be at least 25-30% of the total volume of transfusion media prescribed to compensate for blood loss, t .e. not less than 800-1000 ml.
In chronic DIC, as a rule, transfusion of fresh frozen plasma is combined with the appointment of direct anticoagulants and antiplatelet agents (coagulological control is necessary, which is a criterion for the adequacy of the therapy). In this clinical situation, the volume of transfused fresh frozen plasma is not less than 600 ml.
At serious illnesses liver, accompanied sharp decline the level of plasma coagulation factors and developed bleeding or the threat of bleeding during surgery, transfusion of fresh frozen plasma at the rate of 15 ml / kg of body weight is indicated, followed, after 4-8 hours, by repeated transfusion of plasma in a smaller volume (5-10 ml / kg).
Immediately before transfusion, fresh frozen plasma is thawed in a water bath at 37°C. Thawed plasma may contain fibrin flakes, which does not preclude its use with standard filtered intravenous transfusion devices.
Opportunity long-term storage fresh frozen plasma allows you to accumulate it from one donor in order to implement the principle of "one donor - one recipient", which can dramatically reduce the antigenic load on the recipient.
8.4. Reactions during transfusion of fresh frozen plasma
Most heavy risk when transfusing fresh frozen plasma, is the possibility of transmission of viral and bacterial infections. That is why today much attention is paid to methods of viral inactivation of fresh frozen plasma (plasma quarantine for 3-6 months, detergent treatment, etc.).
In addition, immunological reactions associated with the presence of antibodies in the plasma of the donor and recipient are potentially possible. The heaviest of them is anaphylactic shock, clinically manifested by chills, hypotension, bronchospasm, retrosternal pain. As a rule, such a reaction is due to IgA deficiency in the recipient. In these cases, the cessation of plasma transfusion, the introduction of adrenaline and prednisolone is required. If it is vital to continue therapy with a transfusion of fresh frozen plasma, it is possible to prescribe antihistamines and corticosteroids 1 hour before the start of the infusion and re-administer them during the transfusion.
8.5. Transfusion of cryoprecipitate
V Lately cryoprecipitate, which is medicine obtained from donor blood is considered not so much as a transfusion medium for the treatment of patients with hemophilia A, von Willebrand's disease, but as a feedstock for further fractionation in order to obtain purified factor VIII concentrates.
For hemostasis, it is necessary to maintain the level of factor VIII up to 50% during operations and up to 30% in the postoperative period. One unit of factor VIII corresponds to 1 ml of fresh frozen plasma. Cryoprecipitate obtained from a single blood unit must contain at least 100 units of factor VIII.
Calculation of the need for transfusion of cryoprecipitate is made as follows:
Body weight (kg) x 70 ml/kg = blood volume (ml).
Blood volume (ml) x (1.0 - hematocrit) = plasma volume (ml)
Plasma volume (mL) x (factor VIII level required - factor VIII level present) = required amount of factor VIII for transfusion (un.).
The required amount of factor VIII (unit): 100 units. = number of doses of cryoprecipitate needed for a single transfusion.
The half-life of transfused factor VIII in the recipient's circulation is 8-12 hours, so repeated transfusions of cryoprecipitate are usually necessary to maintain therapeutic levels.
In general, the amount of cryoprecipitate transfused depends on the severity of hemophilia A and the severity of bleeding. Hemophilia is regarded as severe at a level of factor VIII less than 1%, moderate - at a level in the range of 1-5%, mild - at a level of 6-30%.
The therapeutic effect of cryoprecipitate transfusions depends on the degree of distribution of the factor between the intravascular and extravascular spaces. On average, a quarter of the transfused factor VIII contained in the cryoprecipitate passes into the extravascular space during therapy.
The duration of therapy with cryoprecipitate transfusions depends on the severity and location of bleeding, the clinical response of the patient. At large surgical operations or extraction of teeth, it is necessary to maintain a factor VIII level of at least 30% for 10-14 days.
If due to some circumstances it is not possible to determine the level of factor VIII in the recipient, then indirectly it is possible to judge the adequacy of therapy by activated partial thromboplastin time. If it is within the normal range (30-40 s), then factor VIII is usually above 10%.
Another indication for the appointment of cryoprecipitate is hypofibrinogenemia, which is extremely rarely observed in isolation, more often being a sign of acute DIC. One dose of cryoprecipitate contains, on average, 250 mg of fibrinogen. However, large doses of cryoprecipitate can cause hyperfibrinogenemia, which is fraught with thrombotic complications and increased erythrocyte sedimentation.
The cryoprecipitate must be AB0 compatible. The volume of each dose is small, but the transfusion of many doses at once is fraught with volemic disorders, which is especially important to consider in children who have a smaller blood volume than adults. Anaphylaxis, allergic reactions on plasma proteins, volemic overload may be observed during transfusion of cryoprecipitate. The transfusiologist must constantly be aware of the risk of their development and, if they appear, conduct appropriate therapy (stop transfusion, prescribe prednisolone, antihistamines, adrenaline).
Blood transfusion(hemotransfusion) is a medical technology consisting in the introduction into a human vein of blood or its individual components taken from a donor or from the patient himself, as well as blood that has entered the body cavity as a result of trauma or surgery.In ancient times, people noticed that with the loss a large number blood, a person dies. This created the concept of blood as a carrier of life. In such situations, the patient was given fresh animal or human blood to drink. The first attempts of blood transfusion from animals to humans began to be practiced in the 17th century, but they all ended in deterioration and death of a person. In 1848 in Russian Empire The Treatise on Blood Transfusion was published. However, blood transfusion began to be practiced everywhere only in the first half of the 20th century, when scientists found out that people's blood differs by groups. The rules for their compatibility were discovered, substances were developed that inhibit hemocoagulation (blood clotting) and allow it to be stored for a long time. In 1926, in Moscow, under the leadership of Alexander Bogdanov, the world's first institute for blood transfusion was opened (today the Hematological Research Center of Roszdrav), a special blood service was organized.
In 1932, Antonin Filatov and Nikolai Kartashevsky proved for the first time the possibility of transfusing not only whole blood, but also its components, in particular plasma; methods have been developed for the conservation of plasma by freeze-drying. Later, they also created the first blood substitutes.
For a long time, donated blood was considered universal and safe means transfusion therapy. As a result, the point of view was fixed that blood transfusion is a simple procedure, and has a wide range of applications. However, widespread blood transfusion led to the appearance of a large number pathologies, the causes of which were clarified as immunology developed.
Most of the major religious denominations did not speak out against blood transfusion, however, the religious organization Jehovah's Witnesses categorically denies the admissibility of this procedure, since adherents of this organization consider blood to be a vessel of the soul that cannot be transferred to another person.
Today, blood transfusion is considered an extremely responsible procedure for transplanting body tissue with all the ensuing problems - the likelihood of rejection of cells and blood plasma components and the development of specific pathologies, including tissue incompatibility reactions. The main causes of complications that develop as a result of blood transfusion are functionally defective blood components, as well as immunoglobulins and immunogens. When infusing a person's own blood, such complications do not occur.
In order to reduce the risk of such complications, as well as the likelihood of infection with viral and other diseases, in modern medicine it is considered that there is no need for infusion of whole blood. Instead, the recipient is transfused specifically with the missing blood components, depending on the disease. The principle has also been adopted that a recipient should receive blood from a minimum number of donors (ideally, from one). Modern medical separators make it possible to obtain various fractions from the blood of one donor, allowing for highly targeted treatment.
Types of blood transfusion
V clinical practice most often infusion of erythrocyte suspension, fresh frozen plasma, leukocyte concentrate or platelets is required. Transfusion of erythrocyte suspension is necessary for anemia. It can be used in combination with substitutes and plasma preparations. With RBC infusion, complications are extremely rare.Plasma transfusion is necessary with a critical decrease in blood volume during severe blood loss (especially during childbirth), severe burns, sepsis, hemophilia, etc. In order to preserve the structure and functions of plasma proteins, the plasma obtained after blood separation is frozen to a temperature of -45 degrees. However, the effect of blood volume correction after plasma infusion is short-lived. More efficient in this case albumin and plasma substitutes.
Platelet infusion is necessary for blood loss due to thrombocytopenia. Leukocyte mass is in demand for problems with the synthesis of one's own leukocytes. As a rule, blood or its fractions are introduced to the patient through a vein. In some cases, the introduction of blood through an artery, aorta or bone may be required.
The method of infusion of whole blood without freezing is called direct. Since this does not provide for blood filtration, the likelihood of small blood clots that form in the blood transfusion system will enter the patient's circulatory system sharply. This can cause acute blockage of small branches by blood clots. pulmonary artery. Exchange hemotransfusion is a partial or complete removal of blood from the patient's bloodstream with simultaneous replacement of it with an appropriate volume of donor blood - it is practiced to remove toxic substances (in case of intoxication, including endogenous), metabolites, products of destruction of erythrocytes and immunoglobulins (with hemolytic anemia of newborns, post-transfusion shock, acute toxicosis, acute renal dysfunction). Therapeutic plasmapheresis is one of the most commonly used methods of blood transfusion. In this case, simultaneously with the removal of plasma, the patient is transfused in the appropriate volume of erythrocyte mass, fresh frozen plasma, and the necessary plasma substitutes. With the help of plasmapheresis, toxins are removed from the body, the missing blood components are introduced, and the liver, kidneys and spleen are cleansed.
Blood transfusion rules
The need for infusion of blood or its components, as well as the choice of method and determination of the dosage of transfusion, are determined by the attending physician based on clinical symptoms and biochemical samples. The doctor performing the transfusion is obliged, regardless of the data of previous studies and analyzes, personally carry out the following studies :- determine the patient's blood group according to the ABO system and compare the data obtained with the medical history;
- determine the donor's blood type and compare the data obtained with the information on the container label;
- check the compatibility of the blood of the donor and the patient;
- obtain biological sample data.
Infusion of blood or its fractions is allowed only if the Rh factor of the donor and the recipient match. If necessary, it is possible to infuse Rh-negative blood of the first group to a person with any blood group in a volume of up to 0.5 liters (only for adults). Rh-negative blood of the second and third groups can be transfused to a person with the second, third and fourth groups, regardless of the Rh factor. A person with a fourth blood group of a positive Rh factor can be transfused with blood of any group.
The erythrocyte mass of Rh-positive blood of the first group can be infused into a patient with any group with a Rh-positive factor. Blood of the second and third groups with an Rh-positive factor can be infused into a person with a fourth Rh-positive group. One way or another, a compatibility test is mandatory before transfusion. When immunoglobulins of rare specificity are detected in the blood, an individual approach to the choice of blood and specific compatibility tests are required.
When transfusion of incompatible blood, as a rule, the following complications develop: :
- post-transfusion shock;
- renal and hepatic insufficiency;
- metabolic disease;
- disruption of the digestive tract;
- disruption of work circulatory system;
- disruption of the central nervous system;
- impaired respiratory function;
- violation of the hematopoietic function.
- pyrogenic reaction;
- immunogenic reaction;
- allergy attacks;
Indications for blood transfusion
Acute blood loss has been the most common cause of death throughout human evolution. And, despite the fact that for some period of time it can cause serious violations of vital processes, the intervention of a physician is not always in demand. The diagnosis of massive blood loss and the appointment of a transfusion has a number of necessary conditions, since it is these particulars that determine the appropriateness of such a risky procedure as blood transfusion. It is believed that in case of acute loss of large volumes of blood, transfusion is necessary, especially if the patient has lost more than 30% of its volume within one to two hours.Blood transfusion is a risky and very responsible procedure, so the reasons for it must be quite good. If there is an opportunity to effective therapy patient without resorting to blood transfusion, or there is no guarantee that it will bring positive results, it is preferable to refuse transfusion. The appointment of a blood transfusion depends on the results that are expected from it: replenishment of the lost volume of blood or its individual components; increased hemocoagulation with prolonged bleeding. Among the absolute indications for blood transfusion are acute blood loss, shock, incessant bleeding, severe anemia, major surgical interventions, incl. with extracorporeal circulation. Frequent indications to transfusion of blood or blood substitutes are various forms anemia, hematological diseases, purulent-septic diseases, severe toxicosis.
Contraindications for blood transfusion
The main contraindications for blood transfusion :- heart failure with defects, myocarditis, cardiosclerosis;
- purulent inflammation of the inner lining of the heart;
- hypertension of the third stage;
- violation of the blood flow of the brain;
- severe violation of liver function;
- general violation of protein metabolism;
- allergic condition;
- persons who received blood transfusions in the past (more than 20 days ago), especially if pathological reactions were observed after them;
- women who have had a difficult birth, miscarriage or childbirth in the past hemolytic disease newborns and jaundice of newborns;
- persons with decaying cancerous tumors, blood pathologies, prolonged septic processes.
Transfusion of blood substitutes
Today, blood-substituting fluids are used more often than donated blood and its components. The risk of human infection with the immunodeficiency virus, treponema, viral hepatitis and other microorganisms transmitted during transfusion of whole blood or its components, as well as the risk of complications that often develop after blood transfusion, make blood transfusion a rather dangerous procedure. In addition, the use of blood substitutes or plasma substitutes is economically more profitable in most situations than the transfusion of donor blood and its derivatives.Modern blood-substituting solutions perform the following tasks :
- replenishment of the lack of blood volume;
- regulation blood pressure reduced due to blood loss or shock;
- cleansing the body of poisons during intoxication;
- nutrition of the body with nitrogenous, fatty and saccharide micronutrients;
- oxygen supply to body cells.
- hemodynamic (anti-shock) - for the correction of impaired blood circulation through the vessels and capillaries;
- detoxification - to cleanse the body in case of intoxication, burns, ionizing lesions;
- blood substitutes that nourish the body with important micronutrients;
- correctors of water-electrolyte and acid-base balance;
- hemocorrectors - gas transport;
- complex blood-substituting solutions with a wide spectrum of action.
- the viscosity and osmolarity of blood substitutes must be identical to those of blood;
- they must completely leave the body, without adversely affecting organs and tissues;
- blood-substituting solutions should not provoke the production of immunoglobulins and cause allergic reactions during secondary infusions;
- blood substitutes must be non-toxic and have a shelf life of at least 24 months.
Blood transfusion from a vein to the buttock
Autohemotherapy is an infusion to a person of his venous blood into the muscle or under the skin. In the past, it was considered a promising method for stimulating nonspecific immunity. This technology began to be practiced at the beginning of the 20th century. In 1905, A. Beer was the first to describe the successful experience of autohemotherapy. In this way, he created hematomas, which contributed to more effective treatment of fractures.Later, to stimulate immune processes in the body, transfusion of venous blood into the buttock was practiced for furunculosis, acne, chronic gynecological inflammatory diseases etc. Although there is no direct evidence in modern medicine for the effectiveness of this procedure for getting rid of acne, there is a lot of evidence supporting it. positive effect. The result is usually observed 15 days after the transfusion.
For many years, this procedure, being effective and having minimal side effects, was used as an adjunct therapy. This continued until the discovery of broad-spectrum antibiotics. However, even after that, in chronic and sluggish diseases, autohemotherapy was also used, which always improved the condition of patients.
The rules for transfusion of venous blood into the buttock are not complicated. Blood is withdrawn from a vein and deeply infused into the upper-outer quadrant of the gluteal muscle. To prevent bruising, the injection site is heated with a heating pad.
The treatment regimen is prescribed by a physician on an individual basis. First, 2 ml of blood is infused, after 2-3 days the dose is increased to 4 ml - thus reaching 10 ml. The course of autohemotherapy consists of 10-15 infusions. Independent practice of this procedure is strictly contraindicated.
If during autohemotherapy the patient's health worsens, the body temperature rises to 38 degrees, tumors and pains appear at the injection sites - at the next infusion, the dose is reduced by 2 ml.
This procedure can be useful for infectious, chronic pathologies, as well as purulent skin lesions. Contraindications for autohemotherapy on this moment no. However, if any violations appear, the doctor should examine the situation in detail.
Intramuscular or subcutaneous infusion of increased blood volumes is contraindicated, because. this results in local inflammation, hyperthermia, muscle pain, and chills. If after the first injection pain is felt at the injection site, the procedure should be postponed for 2-3 days.
When conducting autohemotherapy, it is extremely important to observe the rules of sterility.
Not all physicians recognize the effectiveness of venous blood infusion into the buttock for the treatment of acne, so last years this procedure is rare. In order to treat acne, modern doctors recommend the use of external preparations that do not cause side effects. However, the effect of external agents occurs only with prolonged use.
About the benefits of donation
According to statistics from the World Health Organization, every third inhabitant of the planet needs a blood transfusion at least once in his life. Even a person with good health and a safe area of activity is not insured against injury or illness, in which he will need donated blood.Hemotransfusion of whole blood or its components is carried out to persons in a critical state of health. As a rule, it is prescribed when the body cannot independently replenish the volume of blood lost as a result of bleeding due to injuries, surgical interventions, difficult childbirth, severe burns. People suffering from leukemia or malignant tumors regularly need blood transfusions.
Donor blood is always in demand, but, alas, over time, the number of donors in the Russian Federation is steadily falling, and blood is always in short supply. In many hospitals, the volume of available blood is only 30-50% of the required amount. In such situations, doctors have to make a terrible decision - which of the patients will live today and who will not. And first of all, at risk are those who need donated blood throughout their lives - those suffering from hemophilia.
Hemophilia - hereditary disease characterized by incoagulability of blood. This disease affects only men, while women act as carriers. At the slightest wound, painful hematomas occur, bleeding develops in the kidneys, in digestive tract, in the joints. without proper care and adequate therapy by the age of 7-8, the boy, as a rule, suffers from lameness. Adults with hemophilia are usually disabled. Many of them are unable to move without crutches or a wheelchair. Things that healthy people do not attach importance to, such as pulling out a tooth or a small cut, are extremely dangerous for people with hemophilia. All people suffering from this disease need regular blood transfusion. They usually receive transfusions made from plasma. A timely transfusion can save the joint or prevent other serious disorders. These people owe their lives to the many donors who shared their blood with them. Usually they do not know their donors, but they are always grateful to them.
If a child suffers from leukemia or aplastic anemia, he needs not only money for medicines, but also donated blood. Whatever drugs he takes, the child will die if he does not make a blood transfusion in time. Blood transfusion is one of the indispensable procedures for blood diseases, without which the patient dies within 50-100 days. In aplastic anemia, the hematopoietic organ, the bone marrow, ceases to produce all blood components. These are red blood cells that supply the cells of the body with oxygen and nutrients, platelets that stop bleeding, and white blood cells that protect the body from microorganisms - bacteria, viruses and fungi. At acute shortage of these components, a person dies from hemorrhages and infections, which do not pose a threat to healthy people. Treatment this disease consists in measures that force the bone marrow to resume the production of blood components. But until the disease is cured, the child needs constant blood transfusions. In leukemia, during the period of acute progression of the disease, the bone marrow produces only defective blood components. And after chemotherapy for 15-25 days, the bone marrow is also not able to synthesize blood cells, and the patient needs regular transfusions. Some need it every 5-7 days, some - daily.
Who can become a donor
According to the laws of the Russian Federation, any capable citizen who has reached the age of majority and has passed a series of medical tests can donate blood. The examination before donating blood is free of charge. It includes:- therapeutic examination;
- hematological blood test;
- blood chemistry;
- examination for the presence of hepatitis B and C viruses in the blood;
- a blood test for the human immunodeficiency virus;
- blood test for treponema pallidum.
What to do before donating blood
Key Recommendations :- stick to a balanced diet, follow a special diet 2-3 days before donating blood;
- drink enough fluids;
- do not drink alcohol 2 days before donating blood;
- during three days before the procedure, do not take aspirin, analgesics and medicines, which include the above substances;
- refrain from smoking 1 hour before giving blood;
- sleep well;
- a few days before the procedure, it is recommended to include sweet tea, jam, black bread, crackers, dried fruits, boiled cereals, pasta without oil, juices, nectars, mineral water, raw vegetables, fruits (with the exception of bananas) in the diet.
Donor Benefits
You can't save lives for financial gain. Blood is needed to save the lives of seriously ill patients, and many of them are children. It is scary to imagine what can happen if blood taken from an infected person or a drug addict is transfused. In the Russian Federation, blood is not considered a trade item. Money given to donors at transfusion stations is considered lunch compensation. Depending on the amount of blood withdrawn, donors receive from 190 to 450 rubles.A donor from whom blood was taken in a total volume equal to two maximum doses and more, certain benefits are due :
- within six months for students of educational institutions - an increase in scholarships in the amount of 25%;
- within 1 year - benefits for any diseases in the amount of full earnings, regardless of length of service;
- within 1 year - free treatment v public clinics and hospitals;
- within 1 year - allocation preferential vouchers in sanatoriums and resorts.
Blood is formed by the combination of a group of substances - plasma and formed elements. Each part is bright expressed functions and performs its unique tasks. Certain enzymes in the blood make it red, but in percentage terms most composition (50-60%) is a liquid of light yellow color. This ratio of plasma is called hematocrine. Plasma gives the blood a liquid state, although it is heavier than water in density. The substances contained in it make dense plasma: fats, carbohydrates, salts and other components. A person's blood plasma can become cloudy after eating fatty foods. And so, what is blood plasma and what are its functions in the body, we will learn about all this further.
Components and composition
More than 90% of the blood plasma is occupied by water, the rest of its components are dry substances: proteins, glucose, amino acids, fat, hormones, dissolved minerals.
Approximately 8% of plasma composition is protein. in turn, they consist of a fraction of albumins (5%), a fraction of globulins (4%), fibrinogens (0.4%). Thus, 1 liter of plasma contains 900 grams of water, 70 grams of protein and 20 grams of molecular compounds.
The most common protein -. It is formed in cookies and occupies 50% of the protein group. The main functions of albumin are transport (transfer of trace elements and drugs), participation in metabolism, protein synthesis, and reservation of amino acids. The presence of albumin in the blood reflects the state of the liver - a low albumin indicates the presence of the disease. Low levels of albumin in children, for example, increase the chance of developing jaundice.
Globulins are large molecular components of a protein. They are produced by the liver and organs of the immune system. Globulins can be of three types: beta, gamma, alpha globulins. All of them provide transport and connecting functions. also called antibodies, they are responsible for the reaction of the immune system. With a decrease in immunoglobulins in the body, a significant deterioration in the functioning of the immune system is observed: permanent bacterial and.
The fibrinogen protein is formed in the liver and, becoming fibrin, it forms a clot at the sites of vascular damage. Thus, the liquid is involved in the process of its coagulation.
Non-protein compounds include:
- Organic nitrogen compounds (urea nitrogen, bilirubin, uric acid, creatine, etc.). An increase in nitrogen in the body is called azotomy. It occurs when there is a violation of the excretion of metabolic products in the urine or with an excessive intake of nitrogenous substances due to the active breakdown of proteins (starvation, diabetes, burns, infections).
- Organic nitrogen-free compounds (lipids, glucose, lactic acid). To maintain health, it is necessary to track a number of these vital signs.
- Inorganic elements (calcium, sodium salt, magnesium, etc.). Minerals are also essential components of the system.
Plasma ions (sodium and chloride) maintain an alkaline blood level (ph), providing normal condition cells. They also play the role of supporting osmotic pressure. Calcium ions are involved in reactions muscle contractions and affect the sensitivity of nerve cells.
During the life of the body, metabolic products, biologically active elements, hormones, nutrients and vitamins enter the bloodstream. However, it does not specifically change. Regulatory mechanisms provide one of the most important properties of blood plasma - the constancy of its composition.
Plasma functions
The main task and function of plasma is to move blood cells and nutrients. It also performs a bunch of liquid media in the body that go beyond the circulatory system, since it tends to penetrate through.
The most important function blood plasma is to carry out hemostasis (ensuring the operation of the system in which the fluid is able to stop at and remove the subsequent thrombus involved in clotting). The task of plasma in the blood is also reduced to maintaining a stable pressure in the body.
In what situations and why is it needed? Most often, plasma is transfused not entirely with blood, but only with its components and plasma fluid. Producing, with the help of special means, the liquid is separated and shaped elements, the latter are usually returned to the patient. With this type of donation, the frequency of donation increases to two times a month, but no more than 12 times a year.
Blood serum is also made from blood plasma: fibrinogen is removed from the composition. At the same time, the serum from the plasma remains saturated with all the antibodies that will resist microbes.
Blood diseases affecting plasma
Human diseases that affect the composition and characteristics of plasma in the blood are extremely dangerous.
Allocate a list of diseases:
- - occurs when the infection enters directly into the circulatory system.
- and adults - a genetic deficiency of a protein responsible for clotting.
- Hypercoagulant state - too rapid clotting. In this case, blood viscosity increases and patients are prescribed drugs to thin it.
- Deep - the formation of blood clots in deep veins.
- DIC is the simultaneous occurrence of blood clots and bleeding.
All diseases are associated with the peculiarities of the functioning of the circulatory system. The impact on individual components in the structure of blood plasma can bring back the viability of the organism back to normal.
Plasma is the liquid component of blood with a complex composition. It itself performs a number of functions, without which the vital activity of the human body would be impossible.
For medical purposes, blood plasma is often more effective than a vaccine, since its constituent immunoglobulins reactively destroy microorganisms.
Considering the risk of possible complications, at present, blood transfusions should be carried out only for absolute (vital) indications.
Indications for transfusion of erythrocyte-containing blood components
Indications for transfusion of erythrocyte blood components are the conditions in which hemic hypoxia develops:
heavy massive acute blood loss after replenishment of the BCC;
severe anemia of other origin, primarily hyporegenerative and aplastic
acute hemolysis (cyanide poisoning, etc.)
poisoning carbon monoxide(in the presence of HBO, the last indication becomes relative)
Indications for plasma transfusion
Plasma transfusion should be understood as the transfusion of fresh frozen plasma (FFP) that has retained labile coagulation factors and immunoglobulins. Non-frozen blank, so-called. "native plasma" is now virtually phased out. Indications for FFP transfusion are very wide, primarily due to the fact that DIC occurs in a large number of diseases:
disorders of plasma hemostasis, primarily acute massive blood loss with the development of DIC
liver disease with insufficient production of plasma coagulation factors
overdose of indirect anticoagulants
exchange plasmapheresis
Indications for transfusion of platelets (platelet concentrate)
Indications for platelet transfusion are quite wide, because DIC - platelet consumption syndrome occurs in a variety of diseases:
thrombocytopenia due to insufficient production of platelets in the bone marrow, threatening or accompanied by hemorrhagic syndrome
thrombocytopenia due to increased destruction of platelets (autoimmune)
acute DIC - a syndrome with increased consumption of platelets
Indications for transfusion of leukocytes (leukocyte concentrate)
Indications for transfusion of leukocytes are currently quite limited, since the selection of a compatible donor according to the HLA system is extremely difficult, and as a result, there are a large number of reactions and complications during transfusion without individual selection. In addition, the effect of leukocyte transfusion does not exceed several days due to the short life span of these blood cells. It also matters that the leukocyte concentrate must be poured within 1 day from the moment of preparation. Thus, the only indication for prescribing a leukocyte concentrate is:
agranulocytosis with a decrease in the absolute number of granulocytes less than 0.5 10 9 / l in the presence of a bacterial infection uncontrolled by antibiotics
Since transfusions of blood components are performed only for absolute (vital) indications, all contraindications are relative. Tactics is based on determining the ratio of the risk of transfusion and possible complications.
Autohemotransfusion and blood reinfusion. Autodonation.
Autohemotransfusion- transfusion to the patient (recipient) of his own (autologous) blood or its components previously taken from him and returned to compensate for blood loss.
There are the following types of autohemotransfusions:
Transfusion of blood or its components prepared in advance from him to the patient.
Transfusion of blood or its components, prepared immediately before surgery using intraoperative normovolemic hemodilution.
Return (reinfusion) to the patient of autologous blood collected during surgery from operating field and (or) poured into the serous cavities as a result of injury or disease.
Unlike transfusion of donor (allogeneic) blood, autohemotransfusion has the following main advantages:
Absence of post-transfusion reactions and complications associated with immunological incompatibility;
No risk of transmission of bloodborne infections (hepatitis B and C, human immunodeficiency virus, syphilis, cytomegalovirus, etc.);
No risk of developing homologous blood syndrome and graft-versus-host disease;
The possibility of providing patients with freshly prepared, immunologically compatible blood components, including patients with a rare blood type;
Possibility of saving resources of donor blood and its components;
Autoblood pre-preparation method:
At the same time, from 250 to 450 ml of autologous blood is harvested. With multiple exfusions (accumulation method) within 2-3 weeks, up to 1000 ml of erythrocyte mass and up to 1200 ml of autoplasma can be prepared. The last exfusion of autologous blood should be performed at least 2-3 days before surgery. It is most preferable to prepare autologous blood components by the hardware method - erythrocytepheresis and plasmapheresis. Storage of autologous blood components is carried out in separate refrigerators under conditions similar to the storage of donor blood.
Intraoperative normovolemic hemodilution
The method of intraoperative autologous blood reservation with the creation of acute normovolemic hemodilution also has its advantages - it is convenient, does not require preliminary blood collection, the reserved blood retains all its qualities, since it is stored for no more than 1-3 hours before returning to the autodonor. The calculation of the volume of extracted blood is carried out according to special formulas
To prevent hypovolemia during or after blood exfusion, an exchange solution is introduced from an equal amount of colloids and crystalloids with an excess of the volume of prepared autologous blood by 20-30%. Reverse transfusion of autologous blood is carried out directly during (with the development of intraoperative blood loss) or after the end of the operation.
Intraoperative blood reinfusion
Reinfusion of blood is a type of autohemotransfusion, which consists in the transfusion of blood that has poured into the serous cavities or is collected directly from the wound during surgery. Blood is taken from the cavity with a sterile electric pump. Stabilization - standard haemopreservatives or heparin (1000 IU per 1000 ml of blood). Fractionation of blood and washing of erythrocytes is carried out in specialized departments or directly in the operating room using special devices such as CellSaver. Previously used filtration through 4 layers of sterile gauze grossly damages the preserved erythrocytes and is prohibited by the current “Instructions for the use of blood components and preparations” (Fig. 45).
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