Donated blood

For quite a long time, preserved donor blood was considered to be the most effective and universal means of treating hemorrhagic anemias, hypovolemic conditions, disorders of protein metabolism of various etiologies, etc. Donor blood was widely used during the Great Patriotic War as the only effective remedy at that time in the treatment of military trauma - acute blood loss. Over time, as far as the development and introduction of high-performance drugs, hemodynamic, rheological, anti-anememic and haemostatic effects, as well as tools that effectively correct protein and water-salt metabolism, have largely limited the scope of use of donor blood. At present, blood transfusion needs to be carried out in accordance with the general principles of component hemotherapy: blood transfusions are performed strictly according to indications and those blood components in which the patient's body lacks.

Donor blood: a place in therapy

Despite the well-founded propagation of component hemotherapy, the use of whole blood has its own, although limited indications: with massive blood loss with pronounced hypovolemic shock and anemic hypoxia, reduced bcc (erythrocytes and plasma), massive exchange transfusions (hemolytic disease of newborns, acute hemolysis, toxicosis , chronic renal failure), especially in military field conditions, catastrophes, when it is not possible to immediately obtain a sufficient number of blood components. In peacetime, especially in planned surgery, with indications for blood transfusion, it is necessary to strictly adhere to the concept of component hemotherapy - to pour out the essential components of donor blood.

The duration of the substitution effect of blood transfusion depends largely on the initial state of the organism. With fever, a high level of catabolism for burns, extensive surgical interventions, sepsis, hemolysis and blood coagulation disorders, it is reduced. In the process of transfusion and the next 2-3 days after it, donor blood causes a volemic effect only if the volume of transfused blood does not exceed 20-30% of the BCC and there are no microcirculatory shifts. Blood transfusion, exceeding 30-50% of BCC, leads to worsening of blood circulation, disturbance of hemodynamics stability, pathological deposition of blood.

The method of autotransfusion should be used in all cases when transfusion of blood components is shown to compensate for blood loss and there are no contraindications to blood exfusion in this patient.

A more pronounced effect of autotransfusions compared with the use of homologous blood can be reduced to the following points:

• higher replacement (anti-anemic) effect;
• more rapid postoperative blood recovery due to hemopoiesis stimulation by a second preoperative blood supply;
• absence of immunosuppressive effect of transfusion;
• economic effect - the reserves of donor homologous blood are preserved.

It is recommended to adhere to two basic rules when deciding the issue of blood transfusion for patients who have been autografted:

• It is better not to use pre-operative autograft (or its components) than to transfuse it to a patient without evidence;
• if necessary, blood transfusions of large doses of blood components first of all, autologous blood must be poured.

The last blood lead should be carried out at least 3-4 days before surgery.

It is possible to recommend a patient to autonomy if two basic conditions are met: compensated functions of organs (cardiovascular, pulmonary, metabolic, hematopoietic) and the exclusion of acute generalized infection, in particular bacteremia / sepsis.

Autocraft canned, filtered. If blood transfusion or auto-erythrocytic mass is necessary within a time period exceeding 2-3 days after the preparation, it is recommended to filter the blood through leuco filters. The removal of leukocytes is the prevention of isensensibilization to leukocyte antigens, hemotransmissive virus infections (cytomegaloviruses-CMV), anaphylactic, allergic reactions caused by leuko-responsins. For leukofiltration, the most optimal is the use of systems for the collection of donor blood, consisting of several interconnected containers with a built-in filter (closed systems).

Preoperative hemodilution - part of the BCC after the patient's blood exfusion is replaced by blood substitutes to a hematocrit level of 32-35%. The collected donor blood is used to compensate perioperative bleeding.

Intraoperative hemodilution - blood exfusion directly in the operating room after an initial anesthesia with reimbursement of plasma substitutes to a level of hematocrit not lower than 30% (in exceptional cases up to 21-22%).

Autograft cavity, canned, filtered for reinfusion (intraoperative autotransfusion, autologous reinfusion) is most effective where the predicted blood loss can be more than 20% of the BCC. With blood loss exceeding 25-30% of BCC, reinfusion should be combined with other methods of autohemotransfusion.

Postoperative autotransfusion is the return to the patient of blood that has been isolated from the drainage in the nearest postoperative period. Safe for blood reinfusion (without washing red blood cells) is hemolysis, which does not exceed 2.5 g / l (250 mg /%) of free hemoglobin. Focusing on the level of free hemoglobin (should not exceed 2.5 g / l), the number of washing procedures is determined - 1, 2 or 3 times, until a colorless supernatant is obtained. In Cell Saver devices, washing is performed automatically in a rotor-bell by physiological solution.

At the same time, it should be borne in mind that in stationary conditions with the correct organization of a transfusiologic benefit in all of the indications listed above, the use of blood hemocomponents is more appropriate and justified from the medical and rational point of view to the use of donor blood and autoblood. Transfusions of whole canned blood in a multidisciplinary hospital, especially in patients with planned surgery, should be considered as a result of the unsatisfactory work of the department of transfusiology and blood service.

[1],

Physiological properties of donor blood

The whole canned donor blood is a non-uniform polydisperse liquid with suspended shaped elements. One unit of canned donor blood (total volume 510 ml), as a rule, contains 63 ml of preservative and about 450 ml of donor blood. Blood density 1,056-1,064 in men and 1,051-1,060 in women. Hematocrit of whole canned blood should be 0.36-0.44 l / l (36-44%). To stabilize the blood most often used hemoconservation, used in the procurement of donor blood, or heparin in physiological solution at a rate of 5 ml per 1 liter.

In adult patients, one volume - 450-500 ml of whole blood raises hemoglobin to about 10 g / l or hematocrit to about 0.03-0.04 l / l (3-4%).

Unfortunately, none of the known hemoconvant does not allow preserving all the properties and functions of blood: oxygen transportation, hemostatic, protective-immunological, delivery of nutrients, participation in water-electrolyte and acid-base metabolism, elimination of metabolic products, etc. For example , red blood cells can retain the ability to carry oxygen for 5-35 days (depending on the preservative used). With hemotransfusions of blood up to 24 hours of storage, almost all red blood cells are immediately included in the work, providing oxygen to the body tissues, and when the canned blood is transfused for long periods of storage (10 days or more), this function of erythrocytes in vivo is restored only after 16-18 hours. In the canned blood to the last day of storage, 70-80% of erythrocytes remain viable. As a result of the cumulative changes, up to 25% of the cellular elements of the preserved blood after the transfusion are deposited and sequestered in the microcirculatory bed, which makes its use for acute blood loss and anemia impractical. A number of the most important biologically active factors of blood plasma, providing regulation of hemostasis: VII, VIII, IX, etc., lose their activity in canned blood after a few hours. Part of the platelets and leukocytes die and disintegrate. At present, donor blood is processed for 6 hours into components - erythrocytes, plasma, platelets and leukocytes and stored in strictly defined conditions for each component: plasma at -30 ° C, red blood cells at 4-8 ° C, platelets at 22 ° C with constant stirring, white blood cells are recommended to be used immediately (for more details, see the relevant section of the chapter).

Pharmacokinetics

Single-group donor erythrocytes after blood transfusion in the recipient organism function from several days to several weeks, which is largely determined by the terms and conditions of storage of red blood cells and the appropriate preservative. Autoerithrocytes are not deposited and circulate in the vascular bed 1,5-2 times longer than donated blood cells.

Contraindications

The main contraindication to transfusion of donor blood and its components (with the exception of special situations, for example, according to vital indications) is the patient's decompensated pathology of the main organs and systems of the body:

• acute and subacute infectious endocarditis with decompensation of blood circulation;
• heart defects, myocarditis in the stage of decompensation of blood circulation;
• pulmonary edema;
• hypertensive disease of stage III with severe atherosclerosis of cerebral vessels;
• billion and disseminated tuberculosis;
• thromboembolism of the pulmonary artery;
• severe liver disorders;
• hepatargia;
• progressive diffuse glomerulonephritis;
• amyloidosis of the kidneys;
• nephrosclerosis;
• hemorrhage in the brain;
• severe disorders of cerebral circulation.

When determining contraindications to transfusion of canned blood, it is necessary to proceed from the fact that the patient should not die from unregistered blood loss, regardless of his pathology.

Absolute contraindications to reinfusion of autoblood are:

• contact of bleeding with the contents of purulent cavities;
• damage to the hollow organs of the abdominal cavity with contamination of the blood with intestinal or gastric contents, contents of cysts, etc .;
• stay autoblood outside the vascular bed for more than 6-12 hours.

Contraindications to preoperative preparation of autoblood from patients:

• anemia (hemoglobin below 100 g / l, hematocrit <0.3-0.34 l / l);
• leukocytopenia and thrombocytopenia (leukocytes <4 x 109 / l, platelets <150 x 109 / L);
• hypoproteinemia (total protein below 60 g / l, albumins below 35 g / l);
• hypotension (blood pressure below 100/60 mm Hg);
• cardiovascular decompensation, unstable angina, recently transferred myocardial infarction, ventricular arrhythmia, AV blockade;
• sepsis, bacteremia, viral diseases, acute inflammatory diseases;
• severe exhaustion and weakness of the patient, adynamia;
• hemolysis of any genesis;
• pregnancy;
• menstruation and the first 5 days after it;
• severe renal dysfunction with azotemia;
• liver damage with hyperbilirubinemia;
• pronounced atherosclerosis of the coronary and cerebral vessels;
• age of patients under 8 and over 75;
• hemophilia;
• epilepsy;
• hereditary blood diseases (hemoglobinopathy and fermentopathy);
• metastasizing cancer;
• thrombosis, thrombophlebitis;
• anticoagulant therapy;
• severe form of bronchial asthma;
• marked violation of the liver, kidneys;
• pronounced manifestations (symptoms) or complications of the disease on the day of the rabbit.

Contraindications to intraoperative hemodilution basically correspond to contraindications for preoperative pre-surgical preparation of autoblood.

[2], [3], [4],

Tolerance and side effects

The shortcomings of blood transfusions should be attributed first of all to the real danger of viral, bacterial and parasitic infection, the possibility of infection with serum hepatitis, syphilis, AIDS and other blood-borne infections.

With prolonged storage, the preserved donor blood loses a number of valuable properties and acquires new qualities that are undesirable for the patient: the potassium content rises, acidosis rises, the pH decreases, the formation and the number of microbots increase. One of the serious and dangerous complications of massive transfusions of donor blood is a complex of pathological disorders, called the syndrome of homologous blood. Complications can occur in the postoperative period. These are delayed anaphylactic reactions, pulmonary distress syndrome, renal and hepatic insufficiency, and others.

Blood transfusion should be treated as a transplant operation with all the ensuing consequences - possible rejection of the cellular and plasma elements of the donor's blood. In patients with immunodepression, transfusion of whole blood is fraught with the development of a dangerous "graft versus host" reaction.

In case of autono- nomy, we must weigh the risk of blood donation, even in severe patients, in comparison with the risks of allogeneic transfusion. Autodonality can be accompanied by a mild headache, a short-term decrease in blood pressure that does not require treatment; 0.3% of donors experience fainting with short-term loss of consciousness, and 0.03% have convulsions, a bradycardia, up to cardiac arrest (such as syncope).

Interaction

Autograft or donor blood is compatible with other blood components and other medicines.

Caveats

Unjustified transfusions of whole blood are not only ineffective, but also often present a certain danger. In the preserved blood during storage there are complex biochemical metabolic processes in cells and plasma, which ultimately reduce the quality of blood and the viability of individual cells. In erythrocytes, the pH, the content of 2,3-DPG, ATP increases, the affinity of hemoglobin for oxygen increases, platelets and leukocytes are destroyed, hemolysis increases, the concentration of potassium ions, ammonia increases, microaggregates are formed from cell elements, active thromboplastin and serotonin are released. Changes in enzyme systems in cells and plasma lead to inactivation or perversion of certain clotting factors. Ultimately, the therapeutic effectiveness of canned blood decreases.

Since the products of vital activity and cell decay accumulate in the preserved blood over time, donor blood of long storage times (<7-14) is not recommended for use in children, in cardiopulmonary bypasses, or in vascular surgery.

Storage times are determined by preserving solutions and billet conditions. Donor blood stored in plastic bags using a sterile closed system and a CPD preservative (citrate-phoshate-dextrose) is stored at a temperature of + 2-6 ° C for 21 days, using a CPDA-1 preservative (citrate-phosphate-dextrose- adenine) - 35 days. Violation of the closed circuit of the system or assembly of the system prior to the procurement of blood and its components limits the shelf life of blood to 24 hours at a temperature of + 2-6 ° C. The use of leuco filters integrated into a closed system of containers does not change the established shelf-life of donor blood and its components. The use of leuco filters that are not built into the system with containers leads to a violation of the integrity of the closed loop, and according to the instruction, the storage time of such medium is reduced to 24 hours.

Transfusion of large volumes of whole blood to produce a therapeutic effect can lead to hypervolemia, cardiovascular overload, isosensitisation, and possible changes in the immune system.

Conserved donor blood should meet the following requirements: integrity of the integrity and integrity of the package; presence of the issued label with instructions of a period of validity and group and Rhesus belonging; at sedimentation to have a clearly expressed boundary of separation into plasma and cellular mass; plasma should be transparent, without turbidity, flakes, filaments of fibrin, expressed hemolysis; the globular (cellular) layer of blood should be uniform, without irregularities on the surface and visible clots.