Hormonal and vitamin preparations used in obstetrics. They are designed for different purposes.
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5.3. INFUSION ENVIRONMENTS IN OBSTETRIC PRACTICE
Infusion media(blood substitutes) are widely used in the removal of pregnant women, women in labor and puerperas from critical (extreme) conditions.
In an uncomplicated course of pregnancy, by the time of delivery, volume shifts are expressed by hypervolemic hemodilution: an increase in BCC by 80% (1000-1200 ml), of which 60% (800-850 ml) due to BCP and 20% due to BCC (200-350 ml) ; hematocrit 30 - 35%. Rheological shifts are manifested by an increase in the relative viscosity of the blood, a decrease in the CODE to 22 mm Hg. Art., a decrease in osmolarity by 10 mosm / l (275 - 280 mosm / l), an increase in erythrocyte aggregation. Increases primary and secondary hemostasis. Compensated metabolic acidosis develops.
During pregnancy complicated by gestosis, iron deficiency anemia, placenta previa, BCC increase is insignificant or absent, CODE below 22 mm Hg. Art., osmolarity below 275 mosm / l. More pronounced increase in relative blood viscosity and erythrocyte aggregation. Violations of hemostasis proceed according to the type of subacute or chronic DIC. Metabolic acidosis is already decompensated.
The choice of blood substitutes should be based on both the volemic, rheological and hemostatic properties of the blood and BOS of pregnant women, as well as on their properties.
Blood substitutes – aqueous solutions organic and inorganic substances administered parenterally to compensate for the deficiency of blood functions and correct pathological conditions of the human body.
Several classifications of blood substitutes have been proposed: A. N. Filatov (1943); A. N. Filatov, I. R. Petrov, L. G. Bogomolova (1958); A. A. Bagdasarov, P. S. Vasiliev, D. M. Grozdov (1969); A. N. Filatov, F. V. Balluzek (1972).
Greatest practical value has a classification of blood substitutes according to the mechanism therapeutic action proposed by A. A. Bagdasarov, P. S. Vasiliev, D. M. Grozdov and supplemented by O. K. Gavrilov (1973):
I. Hemodynamic blood substitutes, derivatives:
- dextran;
- gelatin;
- polyethylene glycol.
II. Regulators for correction of water-salt balance and KOS:
– electrolyte solutions;
– glucose solution 5%;
- electrolyte solutions with 5% glucose;
- semi-electrolyte solutions with 5% glucose;
- osmodiuretics.
III. Solutions for "low volume resuscitation":
- sodium chloride solution 7.2%;
- solutions of sodium chloride 7.2% and artificial colloids.
IV. Infusion antihypoxants:
– fumarate solutions;
- succinate solutions.
V. Blood substitutes with oxygen transfer function:
- solutions of hemoglobin;
– perfluorocarbon emulsions.
VI. Blood substitutes of complex action.
VII. Preparations for parenteral nutrition:
– mixtures of amino acids;
- fat emulsions;
- carbohydrates;
- all-in-one blends (amino acids, fats and carbohydrates).
Hemodynamic blood substitutes designed to normalize the indicators of central and peripheral hemodynamics:
Treatment and prevention of absolute and relative hypovolemia;
normovolemic hemodilution.
They are based on gelatin, dextran, HES and polyethylene glycol. The formulation of hemodynamic blood substitutes determines the following properties:
Maximum hemodynamic efficiency (volemic effect and its duration, maximum daily dose);
Side effects (direct negative effects on primary and secondary hemostasis, hemodilution, acute hyperoncotic kidney injury, the frequency of anaphylactoid reactions and the frequency of itching of the skin and mucous membranes).
Volemic effect (VE)- the ratio of the increase in BCC to the volume of the injected infusion medium in percent (Table 12). The volemic effect and its duration are established empirically on volunteers who, after removing 400 ml of blood, were transfused with 500 ml of a blood substitute for 15 minutes.
Table 12
Hemodynamic efficiency of colloids
Duration of the volemic effect (plateau)- the time during which the volemic effect will be at least 100%.
The volume effect and its duration serve to compare hemodynamic blood substitutes with each other.
Maximum daily dose for all considered hemodynamic blood substitutes is different. In combination with crystalloids, blood components and preparations, they can compensate for blood loss of various sizes (Table 13). However, in practice, it is necessary to take into account the severity of the direct negative influence on hemostasis of dextrans and HES.
to one of side effects a number of blood substitutes should be attributed to their direct negative impact on primary and secondary hemostasis (Table 14).
Dextrans reduce the adhesiveness of platelets, reduce the activity of the von Willebrand factor, have a deaggregant effect on platelets, reduce the activity of the coagulation part of the molecule factor VIII, block the fibrinogen molecule, increase the sensitivity of the fibrin clot to lysis by plasmin, and have a "siliconizing" effect. Degree negative impact dextrans is directly dependent on molecular weight and increases from rheopolyglucin to polyglucin.
Table 13
Compensation of blood loss with hemodynamic blood substitutes
Table 14
Direct negative impact on primary and secondary hemostasis
Note: "-" - does not render; - weakly expressed; - moderately expressed;
- expressed.
HEC due to the "siliconizing" effect, they reduce adhesion and aggregation of platelets, the activity of factors VIII and IX, antithrombin-III and fibrinogen. In HES, the degree of this negative effect is directly dependent not only on the molecular weight, but also on the degree of substitution, and increases from 130/0.42 to 200/0.5 and 450/0.7. According to the instructions, dextrans and HES (200/0.5 and 450/0.7) are contraindicated in severe hemorrhagic diathesis, and caution should be exercised when using HES 130/0.42 (Venofundin).
Derivatives gelatins(gelofusin, gelatinol) and polyethylene glycol (polyoxidin) do not have a direct negative effect on primary and secondary hemostasis. In experiments in vitro when added to donated plasma from 6.7 vol% to 37.5 vol% gelofusin not detected direct reduction ristocytin-cofactor activity of the von Willebrand factor, a decrease in reversible and irreversible ADP-aggregation of platelets, prolongation of APTT, a decrease in factor VIII activity, a prolongation of prothrombin time and a decrease in fibrinogen concentration. Therefore, gelofusin is the hemodynamic blood substitute of choice for infusion therapy of obstetric bleeding, especially those caused by impaired biological hemostasis (DIC, hemodilutional coagulopathy, von Willebrand disease, etc.).
hemodilution effect. Each intravenous injection of 500 ml of hemodynamic blood substitute for 15 minutes reduces hematocrit by an average of 4-6%. With a hemodilutional decrease in hematocrit of less than 28%, hemodilutional coagulopathy and thrombocytopenia may develop.
Colloid osmotic pressure (COD ) is created by blood plasma proteins (mainly albumin) and is one of the regulators of transcapillary metabolism. According to Starling's law, the difference between the forces of filtration and reabsorption in the arterial section of the capillary reaches 7 mm Hg. Art. (under such pressure, the liquid from the capillaries is filtered into the tissues), and on the venous - 7 - 8 mm Hg. Art. (under such pressure, fluid from the tissues enters the vascular bed). From 33 mm Hg. Art. reabsorption forces account for 25 mm Hg. Art. CODEs within the normal range (16.7 - 24.2 mm Hg) have gelatinol (16.2 - 21.4 mm Hg) and stabilizol (18 mm Hg). In 6% of HES (130 / 0.42 and 200 / 0.5), the CODE ranges from 28 - 36 mm Hg. Art. Consequently, with the introduction of a blood substitute with a COD higher than that of blood plasma, conditions are created for the flow of fluid from the interstitial space into the vascular bed. However, when using hyperoncotic solutions: dextrans, especially low molecular weight dextran - rheopolyglucin (COD is 90 mm Hg); 10% solutions of HES 200 / 0.5 (COD is 65 - 80 mm Hg. Art.), the development of the so-called syndrome of acute hyperoncotic kidney injury. There are several hypotheses of the pathogenesis of kidney damage when using colloidal solutions. According to one of them, the development of acute kidney failure(OPN) is associated with the accumulation of low molecular weight fractions in renal tubules and an increase in the osmolarity of urine, which triggers necrotic changes in tubular epithelial cells. According to another, kidney damage is caused by an imbalance between hydrostatic pressure (renal perfusion pressure) and oncotic pressure (blood plasma) on the glomerular membrane. An increase in plasma oncotic pressure is associated with the use of hyperoncotic solutions up to resorption glomerular filtration, which ultimately leads to ischemia and damage to the tubular epithelium.
With the introduction of colloidal blood substitutes of any class, there may be anaphylactoid reactions(Table 15). According to the classification of Ring and Messmer, they are divided into lungs (1 - 2 degrees) and life threatening, or severe (3 - 4 degrees). The frequency (%) and severity (1 - 4 degree) of their occurrence should be indicated in the instructions for use of these drugs. For example, for albumin - 0.099%, gelatinol - 0.155%, gelofusin - 0.0077%, dextrans - up to 7%, HES 200 / 0.5 - up to 0.047% and for HES 450 / 0.7 - up to 0.085%. In order to prevent anaphylactoid reactions, a biological test should be carried out.
Table 15
Degrees of anaphylactoid reactions according to Ring and Messmer (1977)
Long-term daily use of HES in medium (500 ml) and high (1000 ml) doses (total course dose of HES more than 300 g) can cause itchy skin And genitals different intensity and duration. It is associated with the deposition of HES molecules along the nerves and disappears only after the removal or breakdown of HES. Classic antihistamines, antipruritics, ultraviolet therapy and antipsychotics are useless in the treatment of this type of pruritus.
Hydroxyethyl starches (130/0.42; 200/0.5 and 450/0.7) have cytoprotective properties. Highly branched starch molecules form "rivets" in the spaces between endothelial cells throughout basement membrane, effectively eliminating the transcapillary leakage that occurs with many pathological conditions, and protecting endotheliocytes from damage by various agents.
The main route of excretion of all hemodynamic blood substitutes is with urine, only HES are first broken down by blood amylase to fractions. Patients with renal insufficiency have reduced elimination of blood substitutes.
Indications for the use of 6% HES and gelofusin depend not only on the level of hypovolemia, but also on the presence of hemorrhagic diathesis in the patient (Table 16).
Regulators of water and electrolyte balance And KOS designed to correct violations:
Water exchange;
electrolyte exchange;
KOS (metabolic acidosis).
Table 16
Indications for the use of 6% HES and gelofusine in hypovolemia
Note: "+" - shown; "-" - not shown.
These solutions can be conditionally divided into five groups:
1) electrolyte solutions;
2) electrolyte concentrates;
3) osmodiuretics;
4) glucose solution 5%;
5) semi-electrolyte solutions.
The formulation of electrolyte solutions (Tables 17, 18) determines their properties - osmolarity, isotonicity, ionicity, reserve alkalinity.
In relation to the osmolarity of electrolyte solutions to the blood, they exhibit an iso-, hypo- or hyperosmolar effect.
isosmolar effect. Water, chemically bound with ions, is distributed between the intravascular and extravascular spaces as 25% to 75%. The volemic effect (the increase in bcc to the volume of the injected infusion medium in%) will be 100% with jet injection and about 25% 30 minutes after the end of the injection. These solutions are indicated in the treatment of hypovolemia (Table 19).
Depending on the electrolyte content in the solution, they can be isotonic (sodium chloride solution 0.9%), hypotonic (disol, acesol) and hypertonic (sodium chloride solution 10%, potassium chloride solution 4%, sodium bicarbonate solution 4.2 and 8 ,4 %). The latter are called electrolyte concentrates and are used as an additive to infusion solutions (glucose solution 5%, Ringer acetate solution) immediately before administration.
Depending on the number of ions in a solution, monoionic (sodium chloride solution) and polyionic solutions (Ringer's solution, etc.) are distinguished.
The introduction of reserve alkalinity carriers into electrolyte solutions makes it possible to carry out quick (bicarbonate) and delayed (acetate, lactate, malate) correction of metabolic acidosis or maintain the existing CBS (see Table 17).
(see table. 17) depending on the composition, they are used for:
Isotonic dehydration of the extracellular space (due to water chemically bound with ions);
Electrolyte metabolism disorders (due to Na +, K +, Ca 2+, Mg 2+, Cl − ions);
Unchanged CBS (due to BE from -3 to +2.5 mmol / l);
Metabolic acidosis (due to BE more than +3 mmol / l).
Table 17
Isotonic electrolyte solutions
Table 18
Electrolyte solutions (isotonic) 5% glucose
Table 19
The distribution of water between the physiological spaces of the body 30 minutes after the introduction of blood substitutes
Table 20
The rate of administration and maximum doses isotonic electrolyte solutions
Isotonic electrolyte solutions can be administered both through peripheral and through central veins. The rate and maximum daily doses for adults are given in Table. 20.
Electrolyte solutions(isotonic) with 5% glucose are used for:
Isotonic or hypotonic dehydration of the extracellular space;
Electrolyte metabolism disorders (due to Na +, K +, Ca 2+, Mg 2+, Cl - ions);
Metabolic acidosis (due to acetate, malate) and to partially cover energy needs.
Infusion antihypoxants(Mafusol, Reamberin, Sterofundin G-5) are designed to increase the energy potential of the cell (Table 21). They perform the following functions:
1) restore cellular metabolism, activating cell adaptation to oxygen deficiency, due to participation in the reactions of reversible oxidation and reduction in the Krebs cycle;
2) promote recycling fatty acids and glucose cells;
3) normalize acid-base balance And gas composition blood;
4) disaggregate platelets.
Table 21
Infusion antihypoxants
Infusion antihypoxants are indicated for the treatment and prevention of absolute and relative hypovolemia (blood loss, shock), hypoxic conditions various etiologies and intoxications.
5.4. BLOOD COMPONENTS IN OBSTETRIC PRACTICE
Blood components- blood components used for therapeutic purposes, which can be prepared from whole blood by various methods.
Blood components include:
Cellular components (erythrocytes, platelets, leukocytes);
Plasma components (cryoprecipitate, cryosupernatant plasma).
Erythrocyte-containing components(EC) are designed to replace blood loss and treat anemia.
A doctor may have several ECs at his disposal (Table 22).
The choice of EC to replace blood loss depends on its composition and properties.
Massive blood loss of 25–30% of the BCC, accompanied by a decrease in hemoglobin below 70–80 g/l, hematocrit below 25%, and the occurrence of circulatory disorders, is an indication for EC transfusion. It is believed that with normal gas exchange in the lungs critical level oxygen delivery to tissues (Ca O 2) 10 ml / dl is carried out with hemoglobin 65 - 70 g / l.
One dose of transfused donor EC increases the recipient's hemoglobin by an average of 10 g/l, and hematocrit by 4-6%.
Native ECs should be used for up to 3 days in CPD (citrate, phosphate, dextrose) preservative or Glugycyr, up to 5 days in CPDA-1 (citrate, phosphate, dextrose, adenine) preservative, and up to 7 days in SAGM resuspension solution. These recommendations are due to the fact that the main and leading role in the oxygen transport function of donor erythrocytes is played by the intermediate component of glycolysis - 2,3-biphosphoglycerate. After 7 days of storage in the CPD preservative or Glugicir, after 10 days in the CPDA-1 preservative, and after 15 days in the SAGM resuspension solution, the content of this enzyme is reduced to a level at which the dissociation of oxyhemoglobin and the transfer of oxygen to tissues is difficult. Its content in donor erythrocytes after transfusion is restored in the recipient's bloodstream only after 12-24 hours.
Table 22
Composition of erythrocyte-containing components
EC should be poured through a filter with a pore size of not more than 170-200 microns, since platelet aggregates spontaneously form from the first hours of storage. During the day, leukocytes are included in them, and then fibrin strands are formed around platelet-leukocyte aggregates. During subsequent storage, the number of microaggregates ranging in size from 4 to 200 µm progressively increases. Removal during transfusion of microaggregates from 30 to 40 microns prevents microthromboembolism of pulmonary vessels and the development respiratory distress syndrome. There are two ways to reduce the number of microaggregates: 1) use erythrocytes with a removed leukocyte layer or depleted in leukocytes; 2) use microaggregate filters when transfusing erythrocytes.
The use of erythrocytes depleted in leukocytes (less than 1 × 10 6 per dose) helps prevent a number of post-transfusion reactions and complications: HLA-alloimmunization, hyperthermic non-hemolytic reaction, post-transfusion purpura, transmission of cytomegalovirus and Epstein-Barr virus, as well as reduce the incidence of immunosuppression and respiratory distress -syndrome.
Table 23
Platelets: restored
Platelets: restored- component donated blood human, derived from whole blood and containing in a dose most of the platelets in a therapeutically effective form(Table 23).
Reconstituted platelets are used for clinical significant bleeding associated with platelet deficiency.
The dose of transfused donor platelets increases their number in the recipient by 7 ⋅ 10 9 /l.
Fresh frozen plasma(FFP) is a transfusion component of human donated blood, obtained from either whole blood or apheresis-derived plasma, frozen for a specified period of time at a specified temperature to ensure preservation. functional state labile clotting factors.
FFP contains albumins, immunoglobulins, as well as at least 70% of the initial level of factor VIII and at least the same amount of other labile clotting factors and natural inhibitors. A dose of FFP (250 ml) contains an average of 0.75 g of fibrinogen and at least 150 IU of factor VIII.
FFP can be thawed in a water bath (37°C for 20 min) or with a rapid plasma thawer for 12–15 min. Factor VIII activity is best preserved with a rapid plasma thawer.
Immediately after defrosting, the FFP should be poured through a filter with a pore size of no more than 170 - 200 microns. Re-freezing is not allowed.
FFP can be used for coagulation disorders, especially those clinical cases when there is a deficiency of several blood coagulation factors, and in the absence of a suitable virus-inactivated stable drug.
FFP should not be used:
To correct the deficiency of BCC;
In the absence of a deficiency of coagulation factors;
As a source of immunoglobulins;
In patients with intolerance to plasma proteins.
Cryoprecipitate - a component of human donor blood obtained by subsequent processing of FFP and containing a fraction of plasma cryoglobulins.
The drug contains a dose of at least 70 IU of factor VIII, at least 0.14 g of fibrinogen, and the main part of von Willebrand factor, factor XIII and fibronectin.
Cryoprecipitate can be used for:
Conditions with factor VIII deficiency (hemophilia A, von Willebrand's disease with the unavailability of appropriate virus-inactivated drugs);
Other conditions of complex deficiency of clotting factors, such as DIC;
Fibrinogen deficiency (qualitative and quantitative).
Cryosupernatant Plasma- a component of human donor blood, prepared from plasma by removing cryoprecipitate.
The drug contains the same amount of albumin, immunoglobulins and blood coagulation factors as in FFP, with the exception of those that remained in the removed cryoprecipitate.
Shelf life: 24 months. at temperatures below -25 °C, 3 months.
at temperatures from -18 °C to -25 °C.
Thawing can be done in a water bath (37°C for 20 minutes) or with a rapid plasma thawer for 12 to 15 minutes.
Immediately after defrosting, the plasma must be poured through a filter with a pore size of no more than 170 - 200 microns. Re-freezing is not allowed.
The drug can be used for acquired coagulopathy, DIC syndrome blood (when the patient's fibrinogen level is above 1.5 g/l).
Only AB0 compatible plasma should be used.
Informed voluntary consent of the patient for blood transfusion. Fundamentals of legislation Russian Federation on the protection of the health of citizens dated July 22, 1993 No. 5487-1, orders of the Ministry of Health of the Russian Federation, guidelines Funds of compulsory health insurance require prior informed voluntary consent(IDS) of the patient for any medical intervention.
Transfusion of donor blood and its components, even without a defect in their conduction, is associated with the development of reactions and complications and requires IDS for their conduction.
The proposed form for IDS does not provide for the risks associated with violations of the methods and techniques of transfusion.
Before a planned manipulation or surgical intervention, possibly requiring a transfusion of donor blood or its components, the attending physician and (or) anesthetist fills in the patient's IDS (Appendix).
In emergency situations requiring urgent decisions, when the patient's condition does not allow him to express his will, and medical intervention is urgent, the issue of transfusion of donor blood or its components in the interests of the patient is decided by the council, and if it is impossible to convene the council - directly by the attending (duty) doctor with the subsequent notification of the official of the clinic.
Documents on IDS are pasted into the medical history.
1. Helmodynamic (anti-shock)
Low molecular weight dextrans - rheopolyglucin
2. Medium molecular weight dextrans - polyglucin
3. Gelatin preparations - gelatinol
11. Detoxification
1. Low molecular weight polyvinylpyrrolidone- hemodez
2. Low molecular weight polyvinyl alcohol - polydez
111. Preparations for parenteral nutrition
1. Solutions of amino acids.
2. Protein hydrolysates.
3. Fat emulsions - intralipid, lipofundin
4. Sugars and polyhydric alcohols - glucose, sorbitol, fructose
1V. Water-salt and acid-base regulators
1. Saline solutions- isotonic sodium chloride solution, Ringer's solution, lactosol, sodium bicarbonate solution, trisamine solution
MAIN TYPES OF BLOOD SUBSTITUTES
Blood substitutes of hemodynamic (anti-shock) action
High-molecular blood substitutes are mainly hemodilutants, they contribute to an increase in BCC and thereby restore the level blood pressure. They are able to circulate in the bloodstream for a long time and attract intercellular fluid into the vessels. These properties are used in shock, blood loss, when necessary, in the first place. It is the turn to restore the volume of circulating blood and prevent the complex of shock reactions caused by the syndrome of small ejection. Low molecular weight blood substitutes improve capillary perfusion, circulate in the blood for less time, are excreted by the kidneys faster, taking excess fluid. These properties are used in the treatment of capillary perfusion disorders, to dehydrate the body and fight intoxication by removing toxins through the kidneys.
Polyglucin - colloidal solution of polymer glucose - dextran bacterial origin containing a medium molecular weight (molecular weight 60000-10000) fraction of dextran, the molecular weight of which approaches that of albumin, which provides normal colloid osmotic pressure of human blood. The drug is a 6% solution of dextran in isotonic sodium chloride solution. The pH of the preparation is 4.5 - 6.5. Produced in a sterile form in 400 ml bottles, stored at a temperature of -10 to +20 ˚С, shelf life - 5 years. Possible freezing of the drug, after thawing medicinal properties are being restored.
The mechanism of the therapeutic action of polyglucin is due to its ability to increase and maintain BCC by attracting fluid from the interstitial spaces into the vascular bed and retaining it due to its colloidal properties. With the introduction of polyglucin, the volume of blood plasma increases by an amount greater than the volume of the injected drug. The drug circulates in the vascular bed 3-4 days; its half-life is 1 day.
In terms of hemodynamic action, polyglucin surpasses all known blood substitutes, due to colloid osmotic properties it normalizes arterial and venous pressure, improves blood circulation. Polyglucin contains up to 20% of low molecular weight dextran fractions that can increase diuresis and remove toxins from the body. Polyglucin promotes the release of tissue toxins into the vascular bed and then their removal by the kidneys. Indications for its use are as follows: 1) shock (traumatic, burn, surgical); 2) acute blood loss; 3) acute circulatory failure with severe intoxication (peritonitis, sepsis, intestinal obstruction and etc.); 4) exchange blood transfusions for hemodynamic disorders.
The use of the drug is not indicated for trauma to the skull and increased intracranial pressure. A single dose of the drug - 400 - 1200 ml, if necessary, it can be increased to 2000 ml. Polyglucin is administered intravenously drip and jet (depending on the patient's condition). In emergency situations start inkjet introduction drug, then with an increase blood pressure switch to drip infusion at a rate of 60 - 70 drops per minute.
Reopoliglyukin - 10% solution of low molecular weight (molecular weight 35000) dextran in isotonic sodium chloride solution. Reopoliglyukin is able to increase BCC, every 20 ml of solution bind an additional 10 - 15 ml of water from the interstitial fluid. The drug has a powerful deaggregating effect, helps to eliminate blood stasis, reduce its viscosity and increase blood flow, i.e. improves rheological properties blood and microcirculation. Reopoliglyukin has a great diuretic effect, so it is advisable to use it for intoxication. The drug leaves the vascular bed within 2-3 days, but most of its amount is excreted in the urine on the first day. Indications for the use of the drug are the same as for other hemodynamic blood substitutes, but rheopolyglucin is also used for the prevention and treatment of thromboembolic disease, with post-transfusion complications and for the prevention of acute renal failure. The dose of the drug is 500 - 750 ml. Contraindications to the use of the drug are chronic diseases kidney
Gelatinol - 8% solution of partially hydrolyzed gelatin in isotonic sodium chloride solution. The molecular weight of the drug is 20,000. Due to the colloidal properties, the drug increases the BCC. They mainly use the rheological properties of gelatinol, its ability to thin the blood, improve microcirculation. nutritional value the drug does not possess, it is excreted completely within a day with urine, and after 2 hours in bloodstream only 20% of the drug remains. The drug is administered by drip and jet intravenously, intra-arterially, it is used to fill the apparatus cardiopulmonary bypass. The total dose is up to 2000 ml. Relative contraindications to the use of the drug are acute and chronic nephritis.
Transfusion therapy in emergency situations (in the treatment of shock, acute blood loss, acute vascular insufficiency) should start with funds that can quickly restore the bcc. The use of donor blood leads to a loss of 20-30 minutes of time, which is necessary for determining the blood type, compatibility tests, etc. Donor blood has no advantages over colloidal plasma substitutes in terms of the ability to restore BCC. In addition, with shock and a pronounced deficiency of BCC, a microcirculation disorder occurs - a violation of capillary blood flow, the causes of which are an increase in blood viscosity, slugging shaped elements and microthrombosis, which are exacerbated by transfusion of donor blood. In this regard, transfusion therapy should be started in case of shock and even in case of blood loss with intravenous administration of anti-shock blood substitutes - polyglucin and rheopolyglucin.
Blood substitutes of detoxifying action
Gemodez - 6% solution of low molecular weight polyvinylpyrrolidone in a balanced electrolyte solution. Produced in bottles with a capacity of 100, 200, 400 ml, stored at temperatures from 0 to +20 ˚С, shelf life -5 years. Hemodez has a good adsorption capacity: it binds toxins circulating in the blood, including bacterial ones, partially neutralizes them and removes them with urine. The drug is rapidly excreted by the kidneys: after 4-6 hours, up to 80% of gemodez is excreted. Hemodez has the ability to eliminate the stasis of erythrocytes in the capillaries, which is observed during intoxication. By improving capillary perfusion, the drug is able to remove toxins from tissues. Medium single dose hemodeza - 400 ml. The rate of administration of the drug - 40 - 50 drops per minute. Indications for the use of the drug are severe purulent-inflammatory diseases, accompanied by purulent-resorptive fever, purulent peritonitis, intestinal obstruction, sepsis, burn disease, postoperative and post-traumatic conditions.
Similar information.
The modern classification of blood substitutes is based on the features of their action. There are 6 groups of blood substitutes:
Hemodynamic (anti-shock);
Detoxification;
Preparations for parenteral nutrition;
Correctors of water-electrolyte metabolism and acid-base balance;
oxygen carriers;
Preparations of complex action
Hemodynamic (volemic) blood substitutes.
The main pharmacological property of this group of drugs is the ability to increase BCC and thereby eliminate hypovolemia. Volemic drugs include
Saline solutions
Colloidal plasma substitutes
Dextrans
Hydroxyethyl starch preparations (HES, HES)
Gelatin preparations
Polyethylene glycol preparations
Plasma preparations
Poliglukin (Macrodex, Dextran -70) . Medium molecular weight dextran. M=50-70 thousand D, which approximately corresponds (slightly higher) to the molecular weight of human albumin. Available in the form of a 6% solution with the addition of 0.9% sodium chloride. It has a hyperoncotic effect, holding in the vascular bed (or attracting to the vascular bed from the surrounding tissues) up to 3 volumes of water per volume of the injected drug. In this regard, it quickly raises blood pressure in hemorrhagic shock. Volemic action lasts at least 12 hours. Against the background of oliguria and during infusion into large doses often provokes "dextran syndrome").
Reopoliglyukin (Rheomacrodex, Dextran -40) Low molecular weight dextran. M = 30-40 thousand D. It is produced in the form of a 10% solution (Reomacrodex - 12%) with the addition of 0.9% sodium chloride. It has a pronounced antiplatelet effect. Isooncotic. In the vascular bed is kept for about 8-12 hours. "Dextran syndrome" rarely causes, only against the background of prolonged hypotension and oliguria.
HES 6% 0.5 / 200 (Volecam, HAES-steril 6%, Refortan, Infukol) - the most commonly used HES preparation. Isooncotic solution. Effectively replenishes intravascular volume and improves microcirculation. The maximum dose is up to 1.5 liters per day, limited due to the hypocoagulant effect of the drug. The duration of the volemic effect is 3-4 hours.
HES 10% 0.5/200 (HAES-steril 10%, Gemohes 10%, Refortan plus) - according to pharmacological effects, they are similar to HES 6% 0.5 / 200, but due to hyperoncoticity, the intravascular volume is increased up to 150% of the volume of the administered drug.
HES 6% 0.4/130 (Voluven) - differs from HES 0.5/200 by a lesser effect on hemostasis, as a result of which the daily infusion volume can reach 3.0-3.5 liters.
HES 6% 0.7/450 (Stabizol) - significantly inhibits both primary and secondary hemostasis, but also improves microcirculation more significantly than other drugs. The effect lasts at least 6-8 hours. For the treatment of acute blood loss, it is less preferred than other HES preparations.
Gelatinol - 8% solution of partially hydrolyzed edible gelatin in isotonic sodium chloride solution. M=15-25 thousand D., which corresponds to the molecular weight of human albumin. The volemic effect 1 hour after intravenous administration is 60% of the infusion volume. The maximum single dose is 2 liters, limited by the ability of gelatinol to stimulate the release of interleukin-1b and histamine, to reduce the concentration of fibronectin. As a result, the endothelium is sharply damaged and the permeability of the capillary wall increases. There are opinions that Gelatinol can increase bleeding time, worsen clot formation and platelet aggregation, which is due to the increased content of calcium ions in solutions.
A special situation regarding the safety of the use of gelatin solutions has developed due to the threat of the spread of the pathogen of transmissible spongiform encephalopathy of large cattle("mad cow"), not inactivated by conventional sterilization regimens. In this regard, there is information about the danger of infection through gelatin preparations.
Gelofusin - 4% solution of succinated gelatin (modified liquid gelatin, MFG). M=30 thousand D. Isooncotic. The volemic effect persists for at least 5 hours. Reduces blood viscosity and improves microcirculation. 90-95% of the drug is excreted by the kidneys. No damaging effect on the kidneys and other parenchymal organs, no effect on hemostasis was found. Due to the practical absence of side effects, the volume of the maximum infusion is not limited. To date, approaching Gelofuzin to the greatest extent approaching the "ideal volemic plasma substitute".
Polyoxidine. M-20 thousand D. Isooncotic (?). The duration of the volemic effect has not been precisely established. The maximum single dose for adults is 1200 ml. It has antiplatelet properties. May cause nausea, pyrogenic and allergic reactions.
METHYLERGOMETRIN (Increases uterine contractions), ERGOMETRINE MALEAT (increases the tone and increases the frequency of uterine contractions), ERGOTAL (Ergotalum)
A mixture of phosphates of ergot alkaloids. pharmachologic effect. Increases the tone of the muscles of the uterus and increases the frequency of its contractions.
Indications for use. Uterine bleeding caused by atony (loss of tone) of the uterus; to speed up reverse development uterus in postpartum period.
ERGOTAMIN (Ergotamine)
Pharmachologic effect. Increases the frequency and amplitude of uterine contractions, and also has sympatholytic and sedative (calming effect on the central nervous system) properties.
Indication for use. Uterine bleeding, atony (loss of tone) of the uterus, incomplete abortion; migraine.
OXYTOCIN Pharmacological action. Causes strong contractions of the muscles of the uterus (especially pregnant).
Indication for use. For stimulation labor activity, with hypotonic uterine bleeding (bleeding associated with reduced uterine tone) in the postpartum period. It can be used for artificial induction of labor (with complications of pregnancy).
PITUITRIN Pharmacological action. It has oxytocytic (stimulating contractions of the muscles of the uterus), vasopressor (vasoconstrictor) and antidiuretic (reducing the secretion of urine) action.
Indication for use. For excitation and strengthening of uterine contractions with weak labor, post-term pregnancy, hypotonic bleeding (associated with reduced uterine tone) and to normalize uterine involution (uterine contractions in the postpartum period).
NETTLE EXTRACT LIQUID (Extractum Urticaefluidum)
Pharmachologic effect. Has a hemostatic effect various bleeding. Strengthens uterine contractions and increases its tone.
Indication for use. Atony (loss of tone) of the uterus; atonic or hypotonic uterine (associated with decreased uterine tone) bleeding; to accelerate the involution (reduction) of the uterus in the postpartum period. Bleeding from respiratory tract, gastrointestinal tract; nosebleeds.
None of the existing blood substitutes performs the full range of functions inherent in blood, and, having only some properties characteristic of blood plasma, they can only be considered plasma substitutes. This gives grounds to call solutions intended for intravenous therapy either plasma substitutes, or fillers of the vascular bed, or infusion solutions, which creates terminological confusion. If we approach this problem as a problem of modeling various functions and properties of blood, it is possible to create separate compounds that can effectively perform any one function in the body or, like blood, a number of them. Only in this case, the infusion solution obtained on the basis of these compounds can be called a blood substitute. Moreover, if it performs one function, then it is a drug with a directed therapeutic effect, i.e. single-functional blood substitute; If a number of functions, then it is a complex therapeutic drug - a multifunctional blood substitute.
The modern classification of blood substitutes is based on the features of their action. According to this classification, 6 groups of blood substitutes are distinguished: 1) hemodynamic (anti-shock); 2) detoxification; 3) blood substitutes for parenteral nutrition; 4) correctors of water-electrolyte metabolism (WEO) and acid-base balance (CARR); 5) oxygen carriers; 6) blood substitutes of complex action.
Regardless of the group and nature of action, all blood substitutes must have physicochemical and biological properties similar to those of blood plasma, i.e. must be: a) isoionic (have an ionic composition similar to that of blood plasma); b) isotonic (osmotic pressure of blood plasma 7.7 atm); c) isosmolar (290 - 310 mosmol/l); d) not anaphylactogenic (should not cause sensitization of the body or anaphylactic reactions); e) relatively inert to the hemostasis system; e) non-toxic; g) apyrogenic; h) immunoinert; i) easy to manufacture; j) must withstand the necessary sterilization regimes; k) must be stored for a long time in normal conditions and during transportation.
In addition to the basic general properties, blood substitutes must have properties that depend on the functional nature.
Group 1 - hemodynamic(volemic, antishock) blood substitutes combine drugs that give the greatest effect in the infusion therapy of most critical conditions accompanied by hypovolemia. Moreover, the volemic effect is achieved as a result of not only the direct circulation of the drug introduced into the bloodstream, but also the attraction of fluid from the extravascular sector, and in some cases (for individual drugs) due to a decrease in the intensity of deposition processes due to the implementation of the positive rheological properties of the blood substitute. This ability to increase BCC is characterized by a volemic coefficient. The latter represents the amount of increase in the volume of intravascular fluid (in ml) for each milliliter of blood substitute introduced into the recipient's vascular bed. For most anti-shock blood substitutes, it approaches 1 and thus creates a volemic “doubling effect” of the injected volume.
The mechanism of action of anti-shock blood substitutes is determined mainly by their biophysical properties, which can be clearly seen on the example of the action of polyglucin. So, an increase in BCC is achieved by prolonged circulation this drug in the vascular bed due to the content in it of colloidal particles with a molecular weight of more than 40,000 daltons (D), which are not normally filtered by the kidneys. Consequently, the rate of elimination of polyglucin depends on the conditions of its breakdown in the body. As a rule, domestic colloidal blood substitutes (including polyglucin, whose particle mass ranges from 15,000 to 150,000 D) are heterogeneous in molecular weight composition, which causes a variety of their functions and mechanism of action. Thus, low molecular weight fractions of the drug have a rapid hemodynamic effect (high colloid osmotic pressure, accelerated inflow from the extravascular space), significantly improve the rheological characteristics of blood, thereby stabilizing microcirculatory homeostasis and the function of the main parenchymal organs, but quickly leave the vascular bed. At the same time, high-molecular fractions of the drug are able to enhance platelet and erythrocyte aggregation, bind fibrinogen, worsen the rheological characteristics of blood, and stay in the body for a long time (up to several months). The main, average molecular weight of the drug, as it were, eliminates the result of the action of these two simultaneously and oppositely acting mechanisms, which ensures a stable volemic and moderate rheological effect as a whole. Knowledge of all these features of the drug action allows you to more clearly determine the indications and contraindications for its use, taking into account the patient's condition.
Poliglukin. It is a clear, colorless liquid, which includes medium molecular weight dextran (60 g), sodium chloride (9 g), ethyl alcohol (0.3%), water for injection (up to 1000 ml).
The large molecular weight and high CODE of polyglucin determines its retention in the vessels, as well as an increase in the VCP and the volume of extracellular fluid due to the redistribution of fluid from the intracellular to the extracellular sector (1 g of dry matter contributes to the redistribution of up to 26 ml of fluid). The increase in the volume of extracellular fluid is also provided by the osmotic property of sodium chloride; the total volemic coefficient at the same time is quite high.
The bulk of polyglucin introduced into the blood is excreted in the urine (in the first 24 hours - up to 50%), a small part (about 2%) - with feces, the rest is retained (up to 30-60 days or more) in the cells parenchymal organs(in the spleen, liver, kidneys, heart, lungs) and muscles, where it is cleaved by dextran glucosidase to carbon dioxide and water at a rate of approximately 70 mg/kg/day.
Polyglucin is shown in all cases of hypovolemia without pronounced microcirculation disorders; acute circulatory insufficiency with peritonitis, intestinal obstruction, pancreatitis, collapse, burns, etc.; if it is necessary to provide normovolemic intraoperative hemodilution, an operation using cardiopulmonary bypass, etc. There are no absolute contraindications for the use of polyglucin; closed craniocerebral injury with clinical manifestations of intracranial hypertension, cardiopulmonary insufficiency III-IV degree, expressed by microcirculation disorders ("microcirculation deficiency"), DIC syndrome in stage II-III, acute renal failure are considered relative.
Polyglucin solutions are non-toxic, non-pyrogenic. However, it belongs to substances alien to the body, and if in the 60–70s the anaphylactic complications caused by it (more often in the form of reactions) were relatively rare and were explained by the insufficient degree of purity of individual series of the drug, then in last years it has been proven that in humans, as a result of the administration of dextran, protein-polysaccharide complexes are formed that have antigenicity (this property is mainly inherent in high-molecular fractions). Thus, the intake of polyglucin in the body can be accompanied by an anaphylactic reaction of varying severity, up to the occurrence of a fatal anaphylactic shock. To prevent them, before infusion of polyglucin, it is necessary to conduct the same biological test as with the introduction of whole blood. A more effective method of preventing reactions is the creation of new drugs of narrowly targeted action that do not contain high-molecular fractions of dextran.
Rondex(65000±5000 D) - sterile pyrogen-free 6% solution of radiation-modified dextran in 0.9% sodium chloride solution. The relative viscosity of the drug does not exceed 2.8. It is a clear yellow liquid, odorless. Produced in hermetically sealed bottles of 400 ml.
Rondex, due to the narrow molecular weight distribution of its fractions, has better functional characteristics compared to polyglucin and similar foreign drugs. By normalizing central hemodynamics, it actively restores peripheral blood flow by reducing the total peripheral resistance. Rondex is able to increase the electrokinetic potential of the endothelium and erythrocytes, does not have an accelerating effect on the first phase of hemocoagulation, suppresses the adhesive properties of platelets and the intensity of their aggregation. These properties are close to those of rheopolyglucin.
Rondex is used for the prevention and treatment of various types of shock, blood loss, circulatory disorders during surgery, resuscitation and intensive care, hemorheology and blood coagulation disorders, for detoxification, for the treatment of patients with acute and chronic renal failure, etc. Its total daily dose can be increased to 2 liters or more.
Medium-molecular colloidal anti-shock blood substitutes based on dextran perform mainly a volemic function, affecting mainly the central hemodynamics. However, hypovolemia is also accompanied by disorders of the peripheral circulation, which requires an appropriate parallel correction of the rheological characteristics of the blood. Such a rheological activity has a preparation of low molecular weight fractions of dextran - rheopolyglucin.
Reopoliglyukin (30000-40000 D; range of fractions 10000-80000 D) transparent, colorless, or slightly yellow solution of dextran. It consists of low molecular weight dextran (100 g), sodium chloride (9 g), glucose (60 g; in a glucose preparation), water for injection (up to 1000 ml).
Rheopolyglucin can form a molecular layer on the surface cell membranes and vascular endothelium. In this regard, it enhances the electronegativity of erythrocytes and platelets, which leads to the effect of disaggregation, reduces the risk of intravascular thrombosis and the development of DIC, improves the rheological properties of blood and microcirculation and, ultimately, metabolism. The relative fineness of the drug causes high level CODE and contributes to the rapid movement of fluid into the vascular bed, due to which the OCC increases (or normalizes) due to an increase mainly in plasma volume (volemic coefficient of about 1.4). The resulting hemodilution accelerates and enhances the rheological effect, one of the manifestations of which is an increase in diuresis and an acceleration of the excretion of toxic metabolites.
Indications for the appointment of rheopolyglucin are microcirculation disorders, regardless of etiological factor("reversible" shock, burn injury in the acute period, sepsis, "shock" lung, "shock" kidney, etc.); tendency to hypercoagulability and thrombosis; thromboembolic complications; acute period myocardial infarction; intoxication, including acute exogenous poisoning, peritonitis, pancreatitis and others; condition of major surgical interventions.
Relatively contraindicated infusion of rheopolyglucin with severe hyperhydration, accompanied by oliguria; with severe congestive circulatory failure; severe hemodilution (hematocrit less than 0.15 l/l); primary fibrinolysis; ongoing internal bleeding arterial hypotension. Very carefully, the drug should be used either in chroniosepsis or latently flowing purulent infection, since the rapid opening of the peripheral vascular bed can cause a large amount of toxins and vascular-active (vasodilating) substances to enter the bloodstream and the occurrence of severe collapse. To prevent such a complication, reopoliglyukin is poured in 50-100 ml 3-4 times a day, slowly, up to 4 drops per minute.
Some foreign blood substitutes based on dextran, in particular macrodex, rheomacrodes(Sweden), Plasmafusin, Reofusin, Plasmateril, Infucol(Germany), judextraven(France), dextran-70(USA), intradex(Great Britain), dextran-polfa(Poland), Chemodex, Reodex(Yugoslavia) and others, differ from domestic rheopolyglucin in the electrolyte composition of the salt base and a narrower molecular weight distribution of fractions.
Colloidal blood substitutes include gelatin preparations. Gelatin is a high-molecular water-soluble substance that is not a complete protein, since it does not contain the limiting amino acids tryptophan and tyrosine. However, it, unlike other proteins, does not have specificity, and therefore is convenient as a blood substitute.
Gelatinol is an 8% solution of partially hydrolyzed edible gelatin obtained from collagen-containing tissues of cattle. It is a transparent liquid of amber color, easy to foam, contains peptides of different molecular weight.
The mechanism of action of gelatinol is determined by its colloidal properties, similar to those of blood plasma, and manifests itself when administered intravenously by an increase in BCC due to an increase in intravascular volume. However, this increase is small (volemic coefficient of about 0.5) and short-lived. Therefore, gelatinol should be used as an adjunct to anti-shock infusion therapy, especially when it is necessary to provide long-term drip infusions.
Indications for the use of gelatinol are dictated by the mechanism of its action and properties. First of all, this drug is used in the complex therapy of hypovolemia of any origin (shock, blood loss, multiple trauma, etc.), purulent-septic syndrome (in particular, intoxication in acute surgical diseases of the abdominal organs), controlled hemodedulation (including with the use of cardiopulmonary bypass and to fill the apparatus).
Absolute contraindications for gelatinol have not been identified. It is relatively contraindicated in acute and chronic nephritis.
Gelatinol is well tolerated, non-toxic, non-anaphylactic; does not have a negative effect on the blood coagulation system, does not accumulate in the body; combined with all blood substitutes in any ratio.
B o o d e s s a n t e r s o f o f created on the basis of modified (ethoxylated) starch (OEC).
In terms of hemodynamic action, OEC preparations are not inferior to dextrans (polyglucin and its analogues), and in terms of colloid-osmotic properties they are close to albumin. They are non-toxic, do not have a negative effect on blood coagulation, do not cause allergic reactions. Amylopectin starch is similar in structure to glycogen and is able to be broken down by amylopectic enzymes (blood amylase) with the release of unsubstituted glucose. Therefore, the molecular weight of a given drug does not play a significant role in determining its properties, as is the case with dextrans.
Volekam- a domestic drug created on the basis of OEK. Its MM is 170,000 D, DS0.55 - 0.7, i.e. it is similar or close to Japanese. A technological process for obtaining this drug has been developed, and its clinical trials have been carried out.
Group 2 - detoxifying blood substitutes- is a low molecular weight colloids of polyvinylpyrrolidone and polyvinyl alcohol. By stimulating diuresis and having rheological activity, they bind circulating toxins and quickly remove them from the bloodstream.
Hemodez(12600 ± 2700 D) - 6% solution of low molecular weight polyvinylpyrrolidone (PVP-N), which includes polyvinylpyrrolidone-N (60 g), sodium chloride (5.5 g), potassium (0.42 g), potassium (0 .5 g) and magnesium (0.005 g), sodium bicarbonate (0.23 g), water for injection (up to 1000 ml). It is a clear, slightly yellowish, odorless liquid.
The high complexing ability of polyvinylpyrrolidone determines the effect of binding and neutralizing toxins with gemodez (especially in children's intestinal infections, burns), and redeployment of albumin into the bloodstream, blood thinning and a moderate increase in plasma volume - rheological, diuretic and antiplatelet effects of the drug. However, it should be emphasized that these effects appear only when there are no pronounced disorders of the central and peripheral hemodynamics. Like other colloids, hemodez is polydisperse and contains particles with a molecular weight of 10,000 to 45,000 D, and determines the rate of its excretion and the time of onset of the clinical effect, which manifests itself already in the first minutes of administration.
Hemodez infusions are indicated for thermal burns(in the first 3-5 days), acute intestinal obstruction (both in preparation for surgery and in the early postoperative period, destructive forms appendicitis, cholecystitis, pancreatitis, sepsis, peritonitis, liver failure, i.e., intoxication syndrome, including acute endogenous poisoning.
Cardiopulmonary decompensation, hemorrhagic stroke, acute nephritis, bronchial asthma are considered an absolute contraindication for the use of hemodez. Hemodez should also be prescribed very carefully to patients with pulmonary pathology, unstable hemodynamics, and acute renal failure.
Hemodez is administered intravenously, slowly (up to 40-60 drops / min), in daily dose 5 ml/kg. More often, the daily dose is administered in two doses with an interval of 12 hours. Hemodez infusions are carried out daily, during the entire period of toxemia. However, an increase in the dose or duration of the drug does not give a corresponding increase in the effect.
Neohemodes(8000±2000 D) is a 6% solution that has the basic properties of gemodez. However, neohemodesis is less reactogenic, causes a more pronounced rheological effect, stimulates diuresis more strongly. It is indicated for the same pathological conditions and in the same doses as Hemodez.
Polidez(10000±2000 D) is a 3% solution of PVA-N in 0.9% sodium chloride solution. It is a clear, colorless (or slightly yellowish), slightly opalescent solution. The drug is non-toxic, non-antigenic, apyrogenic, rapidly excreted from the body by the kidneys (up to 60-80% - in the first day).
The mechanism of action of polydez is determined primarily by its adsorption properties, which ensure the binding of toxins in the vascular bed. Due to its low molecular weight, polydez is well filtered by the kidneys, stimulating diuresis and renal blood flow. The rheological effect of polydesis is manifested by disaggregation of blood cells in microcirculation vessels.
Polydez is indicated for the same pathological conditions and in the same doses as gemodez. The drug is administered intravenously at a rate of no more than 20-40 drops / min. Daily dose for adults 400 ml.
Group 3 - preparations for parenteral nutrition.
Parenteral nutrition (PN) is a special form of intravenous therapeutic nutrition that provides correction of impaired metabolism (under various pathological conditions) with the help of special infusion solutions that can actively include in metabolic processes organism.
There are total and partial parenteral nutrition.
Total parenteral nutrition(PPP) consists in the intravenous administration of all nutritional components in quantities and ratios that most closely correspond to the needs of the body at the moment. Such nutrition, as a rule, is necessary with complete and prolonged fasting.
Partial parenteral nutrition(NPP) is most often an addition to enteral (natural or probe) if the patient's needs are not met with the help of the latter (due to a significant increase in energy costs, a low-calorie diet, inadequate digestion, etc.).
Carbohydrates for parenteral nutrition it is used in the form of monosaccharides (glucose, fructose, invertose) and alcohols (diatomic - ethanol, butanediol and propanediol; polyhydric - sorbitol, xylitol).
Glucose is the main energy component of both enteral and parenteral nutrition. Most often, 10 and 20% solutions of it are used, somewhat less often - 40 and 50%. Glucose is well absorbed by the body, being actively involved in metabolic processes in all tissues and organs with the formation of 4.1 kcal of energy per gram of metabolized substance.
Insulin plays a large role in glucose metabolism, since it contributes to the "economy" of this process. Therefore, with infusions of large amounts of glucose, parallel fractional (preferably subcutaneous) administration of insulin is necessary at the rate of 1 unit per 3-5 g of glucose.
Fructose, unlike glucose, it is an insulin-independent monosaccharide. In the body, it is absorbed faster and more completely than glucose (by about 20-25%), and therefore its use may be an alternative option for patients. diabetes, with pancreatic necrosis or resection of the pancreas. If liver function is not impaired and small intestine(here mainly its metabolic transformations take place), it is a complete substitute for glucose. In the body, up to 50–70% of fructose is converted into glucose, 20–25% into lactate. When fully utilized, the energy value of fructose is similar to that of glucose. It is most expedient to use 10 and 20% fructose solutions.
ethanol. With a uniform (constant throughout the day) intravenous administration of ethanol at a dose of 1 g/kg/day and a fully functioning liver, no toxic side effects are observed. The absorption of alcohol is also facilitated by the simultaneous use of other carbohydrates. Ethanol infusions are contraindicated in irreversible shock, liver damage, and cerebral coma.
Fats are a high-calorie component of parenteral nutrition. When 1 g of neutral fat is oxidized, 9.3 kcal of energy is released.
Intralipid(Sweden) developed in the 60s. and is a 10 and 20% soybean oil emulsion. It is a milky liquid. It contains essential fatty acids (linoleic - 54.3% and linolenic 7.8%), lecithin egg yolk(emulsifier; 12 g/l) and osmotic corrector glycerol (25 g/l).
Intralipid infusions are indicated in all cases where it is necessary to provide a high caloric intake while limiting the total volume of infusion. It is also used as a necessary supplement to a carbohydrate diet. The use of intralipid is contraindicated in patients in the terminal state and shock, in the early postoperative and post-resuscitation periods, with hyperlipemia, diabetic coma, nephrotic syndrome, liver failure, thromboembolic complications (to prevent the development of the latter, heparin is introduced into the vial - 1 unit per 1 ml of solution).
A group of fat emulsions prepared from cottonseed oil are lipofundin 10% (Finland), lipomul 15% (USA), lipofundin 15% (Germany), And lipifizan 15% (France).
Nitrogen preparations. Protein hydrolysates are solutions containing a mixture of amino acids and simple peptides. They are obtained by acidic or enzymatic hydrolysis of blood proteins of cattle and humans. In connection with the development of more advanced preparations for protein nutrition, the importance of protein hydrolysates has now decreased.
Casein hydrolyzate- acid hydrolyzate of casein - a transparent liquid of straw-yellow or yellowish-cinnamon color with a specific odor. Contains 39.3 g/l amino acids (19.6 g/l - essential); 3.7 - 19.7 g/l of the simplest peptides; 5.5 g/l sodium chloride; 0.4 g/l potassium chloride and 0.005 g/l magnesium chloride; 7-9.5 g / l of total nitrogen (amine - 35-45%). To improve the absorption of amino acids, it is recommended to simultaneously administer potassium (up to 4 mmol / g of nitrogen), glucose (or fructose), and B vitamins.
Hydrolysin-2- improved acid hydrolyzate of bovine blood proteins with a small amount of peptides and humic substances.
A mino acid mixes biological properties surpass protein hydrolysates and practically displace them from use.
Polyamine- 8% solution of a mixture of crystalline amino acids in the L-form and 5% sorbitol (amino acids - 80 g, sorbitol - 50 g, pyrogen-free water - up to 1 l). It is administered intravenously at a rate of 25-35 drops / min in an average daily dose of up to 1000 ml, daily throughout the entire administered drug depends on the amount of protein loss. Polyamine is well tolerated. The inclusion of sorbitol in its composition significantly improves the absorption of amino acids. In terms of clinical and biological properties, polyamine is not inferior to the best and foreign drugs similar functionality.
Vamin "Vitrum"(Sweden) - 7% solution of a mixture of crystalline L-amino acids with fructose (100 g / l) and electrolytes (sodium - 50 mmol / l; potassium - 20 mmol / l; calcium - 2.5 mmol / l; magnesium - 1.5 mmol/l, chlorine - 55 mmol/l); osmolarity 1275 mosm/l; calorie content (fructose) about 400 kcal/l. Total amino acids - 70 g / l (essential - 29 g / l); amine nitrogen - 7.7 g / l.
Macro- and microelements are no less important components of parenteral nutrition.
Main ma c ro elements- potassium, sodium, calcium, magnesium, chlorine - are part of many drugs for PP. In order to correct the electrolyte balance, the content of electrolytes in plasma and erythrocytes is constantly determined, followed by the use of appropriate mono- or polyelectrolyte solutions.
Trace elements - phosphorus, iron, copper, iodine, zinc, fluorine, chromium, manganese, cobalt and others - carry a significant burden in the implementation of various metabolic processes in the body and, under physiological conditions, are supplied in sufficient quantities with food.
Group 4 - correctors of water-electrolyte metabolism and acid-base balance.
Isotonic sodium chloride solution(saline solution) was the first solution used as a blood substitute, including in acute blood loss. The concept of "physiological" 0.85 - 0.9% sodium chloride solution was based on its isoosmoticity with respect to blood plasma. It was soon proved that the "physiological" solution is not physiological at all, because it is not isoionic to blood plasma. It penetrates through the vascular membranes, quickly (within 20-40 minutes) leaves the vascular bed, causing tissue hydration and acidosis. Despite this, it is used in almost all infusion therapy programs as independent drug and as the basis of some complex solutions.
The drug is indicated for various violations body water balance intravenous administration at a dose of up to 2 l / day). With infusions of large volumes of solution (more than 2 liters), hyperhydration of tissues may occur, which leads to edematous syndrome. In such cases, it is recommended to use diuretics. The rate of infusion (drip, jet) is dictated by the specific clinical situation. However, drip infusions are preferred.
Ringer's solution(sodium chloride - 8 g, potassium chloride - 0.3 g, calcium chloride - 0.33 g, water for injection - up to 1 l; or sodium - 140 mmol / l, potassium - 4, calcium - 6, chlorine - 150 mmol/l). The osmolarity of Ringer's solution is 300 mosm/l.
Ringer's solution is compatible with all blood substitutes and blood. The duration of its circulation in the bloodstream is 30-60 minutes. It is closer in salt composition to blood plasma than isotonic sodium chloride solution, and, therefore, is more physiological.
Modifications of Ringer's solution are drugs acesol(contains 2 g sodium acetate, 5 g sodium chloride, 1 g potassium chloride, up to 1 L of water for injection) and chlosol(contains 3.6 g sodium acetate, 4.75 sodium chloride, 1.75 g potassium chloride, up to 1 liter of water for injection).
The group of water and electrolyte balance correctors also includes drugs that have an osmodiuretic effect. These are primarily solutions of mannitol and sorbitol.
Mannitol is a solution of the hexahydric alcohol mannitol. And metabolic processes are involved slightly. Actively excreted by the kidneys. With a jet intravenous infusion of 0.5 - 1.5 g / kg of body weight, 15% mannitol has a powerful diuretic effect due to an increase in the osmotic pressure of blood plasma and a decrease in water reabsorption (solutions below 5% concentration do not have a diuretic effect). Mannitol is indicated (with preserved filtration capacity of the kidneys) for therapy acute edema of the brain during trauma, in post-resuscitation and post-hypoxic periods, during operations on the skull, during detoxification of the body by forcing diuresis, with complications caused by transfusion of incompatible blood, etc.
The drug is contraindicated in anuria, severe cardiopulmonary insufficiency with anasarca.
Sorbitol is a six-hydric alcohol sorbitol. Introduced intravenously at a rate of more than 120 drops / min (stream) sorbitol has an osmodiuretic effect, being included, however, in this case, in the metabolism. Isotonic (6%) sorbitol has a deaggregant effect and thereby improves microcirculation and tissue perfusion.
Electrolytes-correctors of KShchR are used mainly in metabolic acidosis and alkalosis.
Bicarbonate (hybrocarbonate) depending on the level of electrolytes in the plasma, it is used in the form of sodium or potassium salt in molar concentration (8.4% and 10%, respectively). Its action is manifested in 10 - 15 minutes after the start of administration.
Bicarbonate is contraindicated in violation of the excretion of CO 2 (hypoventilation).
sodium lactate Bicarbonate may well be substituted if the patient is predominantly aerobic, where lactate is oxidized to release energy. In severe circulatory failure, especially with impaired microcirculation, sodium lactate is contraindicated.
Group 5 - oxygen carriers- drugs that can perform the function of transporting oxygen without the participation of blood cells.
The positive effect of using blood substitutes in the treatment of blood loss and shock is determined by their volemic and rheological properties, which determine the necessary oxygen transport even with a small amount of red blood cells. However, with a significant loss of erythrocyte volume by the body, a sharp decrease in the oxygen capacity of the blood cannot be compensated only hemodynamically. The inevitable resulting hypoxemia requires appropriate correction by blood infusions, which is not desirable or not always feasible. Therefore, the search for new blood substitutes capable of reversibly binding and transporting oxygen is very important and is being conducted all over the world. The first work in this area was aimed at creating a drug based on hemoglobin. It is known that in the structure of the erythrocyte, the oxygen transport function is carried out by hemoglobin, and the species-specific function is carried out by the proteins of the erythrocyte stroma. Chemically pure hemoglobin freed from the protein stroma is able to reversibly bind oxygen, is not an antigen, and does not have nephrotoxicity. In the form of a drug erygem it has been successfully used in the experiment and clinic for the treatment of blood loss, anemia, coagulation disorders, etc. However, it is characterized by a small oxygen capacity (3.3–4 vol%) and a short circulation time (several hours). In this regard, another drug was subsequently developed - modified polymerized hemoglobin, the oxygen capacity of which reached 10%. It was used to create polyhemoglobinalbumin(a complex of hemoglobin with albumin), which has quite satisfactory hemodynamic and gas transport properties. Nevertheless, in recent years, work on the improvement of these drugs has been suspended, because the direction of creating artificial oxygen carriers based on fully fluorinated hydrocarbon compounds - fluorocarbons (PFS) has turned out to be more promising.
TO fluorocarbons include chemically inert substances, all of whose hydrogen atoms are replaced by fluorine atoms. Fluorocarbons are insoluble in water, and to make them functional, they are prepared into fine emulsions using surfactants (Pluronic, etc.) as the aqueous phase. PPS are able to dissolve gases, in particular oxygen, - 40-50% per unit volume, which is almost 3 times more than water and blood plasma. And an emulated preparation containing 20% fluoroorganic compound can dissolve up to 10% oxygen by volume. The concentration of oxygen physically dissolved in PPS depends linearly on the concentration of oxygen in the emulsion, and the ability to carry oxygen is directly proportional to its concentration in the ambient air.
The most active development of new blood substitutes - oxygen carriers based on PFS emulsion is carried out by firms and research centers in Japan, the USA, France and England. The most commonly used polycyclic hydrocarbons are perfluorodecalin (PFD) and perfluorotripropylamine (PFTPA).
Created in 1973 in Japan by Green Cross Corporation, the drug " Fluosol-DA20» is a 20% PFS emulsion of the following composition (in g per 100 ml of emulsion): perfluorodecalin - 14 g, perfluoripropylamine - 6 g, Pluronic F-68 - 2.7 g, phospholipids - 0.4 g, glycerin - 0.8 g , sodium chloride - 0.034 g, potassium chloride - 0.02 g, magnesium chloride - 0.028 g, sodium bicarbonate - 0.21 g, glucose - 0.18 g, hydroxyethyl starch - 3 g.
In order for the emulsion to have an oxygen capacity comparable to that of whole blood, it must be saturated pure oxygen, and this is not always desirable, and it is not feasible in non-clinical conditions.
It should be noted that the emulsion during internal infusion causes a number of side effects: tachycardia, shortness of breath, arterial hypotension, etc. In addition, it accumulates in the liver and spleen. Despite this, the emulsion still found application in cardiac surgery, including operations on a "dry" heart; in the treatment of anaerobic infections and acute carbon monoxide poisoning; with acute massive blood loss and shock. It is used for preserving and transporting isolated organs, for providing liquid non-ventilated oxygenation, etc.
By 1985, preparations close to foyuosolu-DA were created perftoran And perfucol.
All drugs related to first-generation oxygen carriers have common disadvantages: low oxygen capacity, the need for freezing for long-term storage; long-term retention in the body with a relatively short circulation time in the bloodstream, reactogenicity. All this currently withstands the widespread clinical use of these drugs and forces us to actively continue work on their improvement and creation of new ones.
To group 6 - complex blood substitutes- include semi-functional blood substitutes that simultaneously or sequentially provide two or more effects of action (for example, volemic and detoxifying, anti-shock and nutritional, etc.). These are the above rheopolyglucin(anti-shock, rheological and detoxifying action), gelatinol(anti-shock, detoxifying and nourishing action), as well as specially created reogluman and sormantol.
Reogluman is a 10% dextran solution with a molecular weight of 40,000 ± 10,000 D in 0.9% sodium chloride solution and 5% mannitol. It is a clear, colorless, odorless liquid; pH 4 - 6.5; relative viscosity 7. The properties of the ingredients included in this drug (rheopolyglucin and mannitol) determine its functional purpose: correction of microcirculation disorders, reduction of intravascular aggregation, detoxification. Regluman infusions are carried out for the prevention and treatment of post-resuscitation illness. It is indicated for injuries, burns, extensive surgical interventions. It is also used in vascular and plastic surgery to reduce thrombosis and improve local circulation; in the treatment of centralization of blood circulation in acute blood loss; in the complex treatment of intoxication syndrome; in the treatment of hepatic-renal insufficiency with preserved filtration capacity of the kidneys; in the treatment of post-transfusion complications, etc. This drug is relatively contraindicated in severe hemodilution, hemorrhagic diathesis.
Sormanthol provides a diuretic effect (due to the action of mannitol included in its composition) and serves as an energy substrate (due to the properties of sorbitol). It is a sweetish white powder, highly soluble in any aqueous solutions. Available in 500 ml vials containing 15 g of sorbitol, 15 g of mannitol, 0.04 g of sodium sulfacyl and 1.7 g of sodium chloride. Before use, it is diluted in 200 ml of a solvent (15% solution) and used in conditions accompanied by fluid retention in the body, but with preserved filtration function of the kidneys; as a detoxifying agent, including in liver failure; with intravascular hemolysis, etc. In addition, sormantol accelerates the restoration of intestinal motility in postoperative period, enhances bile secretion, helps to reduce intracranial pressure. It is contraindicated in cardiac decompensation and violation of the filtration capacity of the kidneys.
The mechanism of action of sormantol is based on the hypertonicity of the solution, which provides a rapid osmodiuretic effect, especially in the first hours after administration.
Ecrinol is a bifunctional blood substitute based on modified amylopectin starch. Combines hemodynamic and detoxifying properties.
Aminodes has an active detoxifying effect and contributes to the correction of protein metabolism.
Polyvisoline created on the basis of polyvinyl alcohol with a molecular weight of 10,000 D. It has a pronounced hemodynamic and detoxifying effect.
Polyoxidine created on the basis of polyethylene glycol with a molecular weight of 20,000 D. It has anti-shock, rheological and detoxifying effects.
