Monitoring of objective indicators of the status of parturient women

The dynamics of the cardio-respiratory system

It is known that during pregnancy and childbirth there is a functional reorganization of the cardiorespiratory system, reflecting increasing loads on the respiratory and circulatory organs and is most pronounced in pregnant women, whose pregnancy and childbirth take place against the background of obstetric and extragenital pathology.

Determination of the parameters of the functions of the respiratory and circulatory systems must be carried out in conditions that are as close as possible to the basic metabolism: in the position of the half-lateral position and not earlier than 6 hours after any medication. Women should be examined using gas analyzers. When assessing hemodynamics, it is advisable to use the indirect Fick principle with recurrent respiration. The evaluation of central hemodynamics is carried out by integral rheography using a modified RG-1-01 apparatus.

It is necessary to determine the respiratory rate (BH), the minute breathing volume (MOD), the respiratory volume (DO), the proper vital capacity of the lungs (JEEL), the required minute breathing volume (DMOD) for Dembo-Anthony, the ratio of MOU to DMOD in percent, MOD over the DMOD, functionally dead space (FMP) from the Bohr equation, minute alveolar ventilation (MAB), alveolar volume (AO), respiration efficiency (EE), ventilation efficiency (EV), by capnogram, it is necessary to evaluate its shape, alveolar plateau, Van Meerton index, the corner of the captain the rate of leaching C02 from the dead space, the ratio of the values of inhalation / exhalation, the determination of the point of the beginning of the alveolar phase of expiration, the measurement of the fractional concentration of CO2 in the exhaled air (FeC02), in the alveolar air (FASO2) and at the time of the diffusion termination with respiration (FuC02) . It is necessary to calculate the partial pressure of CO2 in the alveolar basin (PAC02), in the arterial (Pa02) and venous (RUS02) blood.

The main factors that determine blood circulation as a function and its effectiveness are: the volume of circulating blood (BCC); cardiac output (minute volume of heart - MOS); common peripheral resistance (OPS). The listed parameters during pregnancy undergo significant changes.

With a normal course of pregnancy, there are characteristic changes in the circulatory system. The increase in the body weight of the pregnant woman, the increase in intra-abdominal pressure as the uterus grows, the higher the diaphragm and the associated change in the position of the heart, and the formation of the uteroplacental ("third") circulatory system require considerable changes in the circulation system and adaptation to new working conditions.

In pregnancy, there is an increase in the respiratory rate (BH) by 1/3, which is not determinative for ventilation. On the contrary, an increase of 1/3 DO is crucial in adapting the respiratory system during pregnancy. The presence of hyperventilation during pregnancy is associated with an increase in MOU, AO, and the ratio of MOD / DMOD. Hyperventilation, mainly, is carried out by increasing the DO and, to a lesser extent, BH. Ensuring the necessary ventilation is due to the optimal combination of DO, BH, AO and FMP. MAW increases by 70%. In pregnant women, lower parts of the lungs are involved in breathing, where the ventilation-perfusion ratio is improved. Hyperventilation and respiratory alkalosis are a characteristic feature of pregnancy.

Hemodynamics - compensatory increase in heart rate develops, venous return of blood decreases, blood is deposited. The eukinetic type of circulation is created. Hyperventilation serves in these conditions to maintain a volume load on the left heart. In the hemodynamic system, the most informative indicator is systolic blood pressure on the right hand, reflecting cardiac output and increased tone of large arteries.

At the puerperas after the abdominal delivery, the parameters of the function of external respiration and blood circulation on days 1, 2 and 3 persist hyperventilating, exceeding the minute volume of respiration by almost 1.5 times, respiratory alkalosis, hypocapnia with insufficient respiratory compensation of metabolic acidosis, for the expressed unevenness (breathing) of ventilation. Changes in hemodynamics in the puerperas, delivered by the cesarean section, are aimed at the formation of the hypodynamic type of blood circulation, exceeding the minute volume of blood circulation by 1.5-2 times.

With physiologically occurring pregnancy, on the 1st day of the postoperative period, an increase in the oxygen utilization factor by 2 times is characteristic. The value of the minute volume of respiration indicates a significant hyperventilation (7-8 l / min), almost equal to its preoperative level. There is a hypodynamic type of circulation with an increase in the resistance load (total peripheral resistance is 79% higher than during pregnancy).

On the 2nd day after caesarean section, virtually all parameters of the cardiorespiratory system stabilize, except for the general peripheral vascular resistance, which decreases significantly (by 58%) in comparison with the 1-day postoperative period; the hypodynamic type of circulation is preserved.

On the 3rd day, signs of latent parenchymal respiratory failure associated with impaired ventilation-perfusion ratio are revealed; the hypodynamic type of blood circulation is preserved with an increase in systolic volume (by 43%) and an increase (by 35%) in total peripheral resistance in comparison with the 2-day postoperative period.

Thus, the operation of cesarean section leads to a weakening of the regulation of the cardiorespiratory system in the puerperas in the early postoperative period. In most women with physiologically decompensated pregnancy, the link of hemodynamics regulation is most affected, almost all puerperas with diabetes mellitus are the link of gas exchange, in most women who have had late toxicosis of pregnant women, both in the regulation of blood circulation and in the regulation of ventilation are likely.

These data are important for adherence to the principles of infusion and transfusion therapy aimed at correcting the functions of the cardiorespiratory system, in determining the adequate volumes and composition of the injectable solutions, and their optimal ratios.

Monitoring of water balance indicators

By water balance is understood the ratio between the amount of water that has entered the body and separated from it. The water balance is in close relationship with the electrolyte balance. Average daily fluid intake is 2.5 liters, of which 1.2-1.5 liters comes with drinking, 0.8-1 liters with food. About 0.3 liters of water is formed in the body during oxidation processes. In pathological conditions, the water balance is sometimes seriously disturbed. This leads either to the state of dehydration (dehydration) of the body, if the loss of fluid exceeds its intake, or, conversely, hyperhydration, if the liquid enters more than it is released.

For midwifery practice, it is important to consider the total amount of fluid that can be administered to a pregnant woman during labor. The total amount of fluid entering the maternity body during each hour, including dextrose (glucose) for infusion and a solution for oxytocin (if the induction is planned), should average 75-150 ml / h. Pregnant women with heart or kidney disease should be given fewer amounts of fluids; and it is probably advisable to introduce a central venous catheter for more careful monitoring of the incoming fluid.

Electrolytes. It is important to note that, both physiologically and clinically, the exchange of water and sodium in the body is closely interrelated. In pregnancy, the body weight increases partly due to the accumulation of fat (in early pregnancy), and mainly due to water. The total amount of water by the end of normal pregnancy increases by 7.5 liters, which is not accompanied by edema. Great attention is paid to the pathogenesis of water-salt metabolism disorders with certain complications of pregnancy (late toxicosis, etc.). During pregnancy, water retention in the body is combined with an increase in the sodium content, and thus a new, characteristic for pregnancy, level of osmotic pressure remains. During pregnancy, the mechanism is stimulated both in terms of increasing sodium secretion and its preservation. The change in sodium metabolism in pregnancy is closely related to hyperventilation. Thus, with late toxicosis of pregnant women, renal blood flow and glomerular filtration decrease and water and sodium retard. In normal pregnancy, most of the water is outside the cells.

Metabolism of potassium. Regulation of the balance of potassium is extremely important in maintaining homeostasis. Under normal conditions, a person consumes 60-100 mmol of potassium per day with food; from this amount from 5 to 10 mmol is excreted with feces, less than 5 mmol with sweating and the rest with urine. The total potassium reserves in the body are approximately 40-45 mmol / kg body weight. Of this amount, 90% of potassium is in the intracellular space and easily enters into an exchange with 2% located in extracellular fluid spaces; The remaining 8% of potassium is found in bone tissue and is not accepted for rapid metabolic processes. The normal concentration of potassium in the extracellular fluid ranges from 3.6 to 5 mmol / l. The intracellular concentration of this ion is from 140 to 160 mmol / l.

Hypercalcemia. An increase in the serum calcium concentration can be defined as an increase in the serum calcium concentration above the upper limit of the norm (recommended level). The upper limits of calcium concentration recommended by different laboratories are insignificantly different from each other, and the most frequently given values are in the range from 8.5 to 10.5 mg% (2.15-2.60 mmol / l).

In the bloodstream, calcium is contained in three forms: ionized, protein-bound and complex. The complex fraction is approximately 10% of the total calcium and is a calcium compound with phosphate, bicarbonate, citrate and other ions. The fraction associated with proteins is approximately 40%, with the main binding protein being albumin. Ionized fraction is about 50% of the total calcium in the serum. It is considered physiologically active, which is not only under the control of humoral mechanisms, but also itself affects the secretion of hormones.

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