RU2413502C1 - Asn-bokeriya-boldyrev cardioplegic solution - Google Patents

Abstract

FIELD: medicine, pharmaceutics. ^ SUBSTANCE: invention refers to medicine, namely to cargiosurgery, and represents a cardioplegic solution containing sodium chloride, potassium chloride, magnesium chloride, calcium chloride, L-carnosine, N-acetylcarnosine, water for injections differing by the fact that the solution in addition contains mannitol and L-histidine components of which are taken in a certain ratio. ^ EFFECT: invention provides higher buffer capacity and decreased osmolarity of the cardioplegic solution with physiological parametres pH that leads to effective cardiac resuscitation and higher restoration of warm activity and high myocardial contractility after oxidation process. ^ 1 ex, 4 tbl

Description

The invention relates to medicine, namely to cardiac surgery, and is used in open heart surgery for intraoperative myocardial protection in conditions of hypothermia.

Known cardioplegic solution of Boldyrev for intraoperative protection of the myocardium (Comparison of the protective effect of carnosine and acetylcarnosine in the process of cardioplegia / A.A.Boldyrev, V.V. Alabovsky, A.A. Vinokurov and others // Bulletin of experimental biology and medicine. - 1999. - No. 3. - S.290-294), which consists of: sodium chloride - 110 mmol / l, potassium chloride - 16 mmol / l, magnesium chloride - 16 mmol / l, calcium chloride - 1.2 mmol / l, bicarbonate sodium - 20 mmol / l, L-carnosine - 5 mmol / l, N-acetylcarnosine - 10 mmol / l, water for injection - 1000 ml; content in grams: sodium chloride - 4.5 g, potassium chloride - 1.21 g, magnesium chloride - 3.232 g, calcium chloride - 0.48 g, sodium bicarbonate - 1.82 g, L-carnosine - 1.13 g , N-acetylcarnosine — 2.62 g. At the indicated electrolyte content, the buffer capacity of the solution was 7.5–8.2 meq / l · unit. pH, and the pH of the solution was 7.8. Based on the concentration of salts in the solution, Boldyrev's solution is hyperosmolar (osmolarity - 380-390 mosm / l).

The solution is prepared with mandatory fine cleaning. All ingredients should be 100% -110% of the specified amount. The solution is filtered through a sterile 0.2-micrometer filter into a sterile dish with a graduated scale of 400 ml, in bottles of neutral glass grade 1, corked with rubber stoppers with metal run-in. The solvent is pyrogen-free water, obtained by a high degree of purification. Sterilization mode at a temperature of 120 ° C and a pressure of 1.1 atm for 8 minutes. After the product is released, its full chemical analysis is carried out in the laboratory.

The disadvantage of this ready-made solution was high osmolarity with a low buffer capacity, which led to cell edema. The problem of hyperosmolarity is widely disclosed in the literature. In particular, it was found that the postischemic function of the ventricles when using a hyperosmolar solution is less well tolerated than solutions with an osmolarity of 320-340 mosm / l (Elective cardiac arrest / Melrose DG, Dreyer B, Bentall MB, Baker // JBE :. Lancet. - 1955 . - 2:21).

The technical result is to increase the buffer capacity with a decrease in the osmolarity of a cardioplegic solution with physiological pH parameters, which leads to an effective restoration of cardiac activity and high myocardial contractility after oxidative stress.

With the isolated use of L-carnosine in a cardioplegic solution of less than 5 mmol / L, without N-acetylcarnosine and L-histidine, a low myocardial contractility was noted. This was associated with low osmolarity (less than 210 mosm / l) and low pH of the solution (6.9), which led to cell edema and severe acidosis. To increase the osmolarity, 100 mmol / L of L-carnosine was added to the solution, as a result of which the pH of the solution increased to 7.8, and the osmolarity to 300 mosm / l. To stabilize the pH to the level of physiological parameters (7.2-7.5), N-acetylcarnosine at a concentration of 40 mmol / L was used. With the isolated use of N-acetylcarnosine at a concentration of 40 mmol / L, low osmolarity and pronounced acidosis were obtained. The combined use of N-acetylcarnosine with L-carnosine and L-histidine at the same concentration led to an effective restoration of cardiac activity in the postischemic period and an increase in myocardial contractility, as a result of normalization of the solution pH to 7.35-7.45. To stabilize the osmolarity of the solution, mannitol (osmotic diuretic) was added to dipeptides at a concentration of 25 mmol / L, which prevents cell edema and, therefore, contributes to the effective restoration of cardiac activity. Thus, with the combined use of dipeptides and mannitol at the indicated concentrations, the osmolarity of the solution was 320-340 mosm / l.

The proposed cardioplegic solution "ASN" contains: K - 14-16 mmol / L, Na - 100-110 mmol / L, Ca - 0.025-0.04 mmol / L, Mg - 15.5-16 mmol / L, mannitol 20-30 mmol / L, L-histidine - 4.5-7.0 mmol / L, L-carnosine - 90-110 mmol / L, N-acetylcarnosine - 35-50 mmol / L; content in grams: sodium chloride - 4.30-4.62 g, potassium chloride - 1.092-1.156 g, magnesium chloride - 3.19-3.485 g, 10% calcium gluconate solution - 0.0105-0.013 g, mannitol - 4.365-4.520 g, L-carnosine - 21.1504-24.1650 g, N-acetylcarnosine - 8.056-11.032 g, L-histidine - 0.705-0.820 g.

Water for injection - 1000 ml.

The solution has the following physical properties: osmolarity - 320-330 mosm / l, pH - 7.25-7.42 at a storage temperature of the solution - + 4-10 ° C, the temperature of the solution upon administration - + 12-14 ° C, buffer capacity solution - 30-33 meq / l · units. pH The dose of the injected solution during the operation is from 300 to 8000 ml.

The solution is prepared with mandatory final fine cleaning. All ingredients should be 100-110% of the specified amount. The solution is filtered through a sterile 0.2-micrometer filter into a sterile dish with a graduated scale of 400 ml, in bottles of neutral glass grade 1, corked with rubber stoppers with metal run-in. The solvent is pyrogen-free water, up to 1000 ml, which is obtained with a high degree of purification. Dry, pre-weighed substances containing electrolytes: sodium chloride, potassium chloride, magnesium chloride are successively added to water, and calcium chloride is added, then L-carnosine, N-acetylcarnosine, L-histidine, in concentrations in the range of 90-110 mmol / l, 35-50 mmol / l, 4.5-7.0 mmol / l, respectively, which allows to obtain the maximum buffer capacity of the cardioplegic solution with physiological parameters of pH and osmolarity. To stabilize osmolarity, mannitol, which is an osmotic diuretic, is added to the solution with dipeptides. At a concentration of 25 mmol / l in the combination of dipeptides, it prevents the hyperosmolarity of the cardioplegic solution and thereby the effective restoration of cardiac activity, which is the achievement of a technical result.

Example.

A solution was prepared containing: K - 15 mmol / L, Na - 110 mmol / L, Ca - 0.03 mmol / L, Mg - 16 mmol / L, Mannitol - 25 mmol / L, L-histidine - 5 mmol / L , L-carnosine - 100 mmol / L, N-acetylcarnosine - 40 mmol / L, osmolarity - 330 mmosm / L, the pH of the solution was 7.2-7.4; content in grams: sodium chloride - 4.5 g, potassium chloride - 1.125 g, magnesium chloride - 3.232 g, 10% calcium gluconate solution - 0.012 g, mannitol - 4.4 g, L-carnosine - 22.6 g, N -acetylcarnosine - 10.72 g, L-histidine - 0.775 g; the buffer capacity of the solution was 30 - 33 meq / l · units. pH The component of the prepared solution was 1000 ml water for injection.

The solution was prepared with mandatory final fine cleaning. All ingredients accounted for 100% of the indicated amount. The solution was filtered through a sterile 0.2-micrometer filter into a sterile dish with a graduated scale of 400 ml, in bottles of neutral glass grade 1, corked with rubber stoppers with metal run-in. The solvent was pyrogen-free water in a volume of 1000 ml, which was obtained with a high degree of purification. Dry, pre-weighed substances containing electrolytes were successively added to the water: sodium chloride, potassium chloride, magnesium chloride, mannitol and calcium chloride.

Then, L-carnosine, N-acetylcarnosine, L-histidine were successively added to the resulting saline solution. Sterilization mode - at a temperature of 120 ° C and a pressure of 1.1 atm for 8 minutes. After the product was released, its complete chemical analysis was performed in an express laboratory.

The use of N-acetylcarnosine, L-carnosine and L-histidine in combination with mannitol in the above concentrations in a cardioplegic solution allowed us to provide high buffer capacity at isoosmolarity of the solution and physiological pH values of 7.2-7.4, since in the range of physiological pH values used amino acids exhibit the best cardioprotective properties.

Hypothermic ischemia under the conditions of myocardial protection with the proposed cardioplegic solution was performed on the hearts of rats. To evaluate and compare the cardioprotective properties of the prototype solution and the proposed solution, a study was performed on a retrograde perfusion apparatus for an isolated rat heart using the Langendorf method.

The clamp blocking the flow of perfusion solution into the cannula was opened completely, which increased the flow of perfusion solution into the cannula to 12-15 mm / min. Using a mechanism that regulates the depth of immersion, a catheter for measuring pressure was inserted into the left ventricle. Then the lungs were cut off. As a result, perfusion and cardioplegic solution from the aorta entered the coronary arteries, nourished the heart and exited through the veins of the heart into the right atrium. When the right atrium and right ventricle contracted, the solution flowed out through the pulmonary trunk, superior and inferior vena cava, washing the heart.

A cardioplegic solution, the temperature of which was + 12-14 ° C, was administered antegrade, for 5 minutes. After that, the heart was placed on a bowl with a Krebs-Henselyait solution in a thermostat for 480 minutes, at a temperature of + 8 ° C. Then reperfusion was carried out by normothermic perfusion solution with an assessment of cardiac activity.

Assessment of cardiac activity was carried out by continuous recording of the pressure curve in the left ventricle. For this, a polyethylene catheter 0.75 mm thick, filled with fluid and connected to a pressure transducer, was inserted into the cavity of the left ventricle through the aorta. The pressure sensor signal through the preamplifier was fed to the input of the analog-to-digital converter of the computer every 5 milliseconds (an average of 100 points per cardiac cycle) and was recorded using the Pulsar program. The registration was carried out with a sampling frequency of the analog signal of 0.2 kHz, which made it possible to accurately register the pressure curve in the left ventricle. Then, using the Pulsar program, the following parameters were calculated: systolic pressure (SD, mmHg), of course diastolic pressure (KDD, mmHg), developed pressure - amplitude, was calculated as the difference between SD and KDD, mm RT .st .; heart rate of an isolated heart (heart rate, beats / min). Heart rate was calculated as the reciprocal of the duration of the period (P) between the maxima of the pressure in the left ventricle in minutes (heart rate = 1 / P). In addition, we calculated + dp / dt max - the maximum velocity of the pulse wave front (pressure wave) in the left ventricle (i.e., the maximum first derivative of the pressure rise curve), -dp / dt max - the maximum pulse wave decay rate and contractility. After calculating the parameter values for each cardiac cycle, these parameters were calculated for a certain period of time (at 15, 30 and 45 minutes of reperfusion) using the Pulsar program.

The first group is a prototype solution.

The second group is the proposed solution.

The nature of the restoration of cardiac activity: in the first group, independent recovery of cardiac activity was observed in only two out of 18 preparations; in other cases, defibrillation was required; in the second group, independent recovery of cardiac activity was noted in 13 of the 18 drugs.

Table 1 Heart rate dynamics at the main stages of reperfusion (average values) Stages of reperfusion, min Heart rate, beats / min I group II group fifteen 189 209 thirty 202 241 45 219 250

table 2 Dynamics of average values of the maximum velocity of the pulse wave front at the main stages of reperfusion Stages of reperfusion, min + dp / dt max I group II group fifteen 1082 1618 thirty 1168 2080 45 1303 2268

Table 3 Dynamics of average values of the maximum pulse wave decay rate at the main stages of reperfusion Stages of reperfusion, min -dp / dt max I group II group fifteen 632 1232 thirty 828 1498 45 951 1627

Table 4 Dynamics of average amplitude values at the main stages of reperfusion Stages of reperfusion, min Amplitude, mmHg I group II group fifteen 43.7 63.3 thirty 48.5 69.8 45 46.3 74.1

In a comparative aspect, the proposed solution after prolonged ischemia (480 minutes) and hypothermia (+ 12-14 ° C) contributes to a more effective restoration of cardiac activity and increased myocardial contractility with minimal rhythm and conduction disturbances compared to other solutions. When using the proposed solution in the postischemic period, prevalence of aerobic oxidation was noted, oxygen debt and lactate level (l) were minimal (lIII (0.05 ± 0.02) <lII (0.15 ± 0.03) <lI (0.25 ± 0.03).

The estimated buffer capacity of the proposed solution was 30-33 meq / l · units. pH, which is 1.5 times higher than the buffer capacity of the blood, and the isosmolarity and physiological values of the pH of the solution correspond to the requirements for cardioplegic solutions. Histochemical examination of the myocardium with various methods of protection showed that the use of the proposed solution helps to reduce contracture changes in the myocardium, histidine-containing dipeptides in combination with an osmotic diuretic prevent the formation of fatty degeneration in the foci of ischemia and cell edema.

Thus, the results obtained confirming the high cardioprotective properties of the proposed solution. A comparative study showed the advantage of the new solution over other known prototypes.

The resulting solution contributes to the effective restoration of cardiac activity after prolonged ischemia, a decrease in metabolic disorders and contractural myocardial damage.

Claims (1)

Cardioplegic solution containing sodium chloride, potassium chloride, magnesium chloride, calcium chloride, L-carnosine, N-acetylcarnosine, water for injection, characterized in that the solution additionally contains mannitol and L-histidine in the following ratio, g:
sodium chloride 4.30-4.62 potassium chloride 1,092-1,156 magnesium chloride 3,190-3,485 calcium chloride 0.0105-0.0130 mannitol 4,365-4,520 L-carnosine 24,1504-24,1650 N-acetylcarnosine 8,056-11,032 L-histidine 0.705-0.820 water for injection, ml one hundred