The IRGT method is based on the registration of the total pulse measurement of the electrical conductivity of the entire body during the forced passing of alternating current (30 kHz) in a series circuit: hands-trunk-legs. The integral rheogram is a total pulse plethysmogram of the entire arterial system as a whole. The reliability of the method was repeatedly tested in the 70s by comparison with the most accepted methods for measuring the minute volume of blood circulation. The mean square value of random errors of the IRGT method for multiple measurements does not exceed 6%, which causes the high resolution of the method .

Where: Qs – stroke volume of the left ventricle in ml; UI — left ventricular shock index as the ratio of stroke volume to patient surface area in ml / m 2 ; CDI — coefficient of respiratory changes in stroke volume, which is the ratio of the maximum value of the stroke volume to the minimum for one breathing cycle; HR – heart rate (beats / min); Qf — minute volume of blood circulation in l / min; SI —heart index as the ratio of the minute volume to the surface area of ​​the patient’s body in l / min / m 2 ; КР – reserve ratio, representing the ratio of the actual minute volume to the due, calculated taking into account height, weight, sex and age of the patient; KIT is an integral tonicity factor that quantitatively characterizes the state of systemic arterial tone.

Analysis and systematization of large clinical material allowed, using the sigma interval, to offer a quantitative probabilistic assessment of heart failure, which was based on a shock index. As the experience of using heart failure assessment to reduce the shock index, has shown, it allows you to quickly and reliably detect the “preclinical” phase of cardiac dysfunction .

A similar probabilistic quantitative approach was used as the basis for circulatory insufficiency in terms of cardiac index. In such an assessment, there are no differences between men and women, since due to a more frequent pulse with a significantly lower impact index in women, the heart index is not different from the male one. The cause of a lower shock index in women is the load of the left ventricle with higher arterial impedance .

Although the assessment system in the table has been designed to characterize rapid changes in the functioning of the circulatory system, clinical experience has shown that it is applicable to the assessment of chronic conditions. So changes

cardiac index in stages mitral stenosis obtained fully meet the quantitative criteria separation conditions in this probabilistic assessment showed that between reducing cortisol levels in the plasma and magnitude of the correlation is shown in UI if the MI value is less than 38ml / m 2 ,those. This value characterizes the onset of heart failure. Evaluation of heart failure by heart index is traditional for domestic and foreign medicine, but it does not take into account age-related changes in blood circulation. In assessing circulatory failure, this introduces certain difficulties. To overcome this contradiction, he suggested using a new indicator — the reserve ratio of men and for women showed that in healthy people over 16 years old, who are in physiological rest (lying) outside the basal metabolic conditions, the proper value of the minute circulation volume can be determined reliably as Qdp = 1 , 35. Where Qdp is the proper value of the minute volume of blood circulation for the conditions of the main exchange according to. Since the last value includes the individual value of the proper basal metabolism with regard to age, then the Qdp value automatically takes this into account. Reserve ratio (CR) is the ratio of the actual (measured) minute volume of blood circulation to the proper value for rest conditions (Qdp). Such a name was given to the CD because with its help it is convenient to assess various stress, including hypoxic reactions. Repeated checks have shown that the CR value is stable and amounts to 1.0 ± 0.1 for people of different ages . The latter makes it possible to assess the circulatory insufficiency of the patient, taking into account his age, sex, body weight, height — that is, individual features. This rating system is fully consistent with the heart index estimate (taking into account age), but it is simpler and more convenient for operational use.

It should be noted that the clinical assessment of patients with chronic circulatory failure (mitral defects, pericarditis) may be less “hard” than arising from the degree of changes in the main hemodynamic parameters. The latter is explained by the presence of compensation mechanisms (an increase in the globular volume, an increase in arterio-venous difference, etc.) aimed at reducing the deficiency of oxygen transport. However, the assessment of actual circulatory disorders in these patients does not lose its value. When assessing circulatory conditions, situations often arise where, even in the presence of cardiac insufficiency (decrease in cardiac index) of a primary or secondary nature, there may not only be circulatory insufficiency, but a significant increase in the minute volume of blood circulation develops due to tachycardia, which is especially characteristic of lung diseases . Naturally, in such situations, the state of hemodynamics can not be regarded as prosperous. Stselyu identify patterns of hemodynamic changes in the presence of respiratory failure sufficiency The association of indicators of respiratory function with long-term lung diseases was investigated. Analysis of hemodynamic criteria showed that significant changes (according to the degree of dysfunction of respiratory function) undergo a reserve factor and coefficient of respiratory changes in the left ventricular stroke volume, which is the ratio of the maximum value of the stroke volume to the minimum for one breathing cycle (CDI). Thus, the reserve ratio is directly related to the decrease in the vital indicator of external respiration. The reduction of the latter “requires” a certain forcing of the minute volume of blood circulation.

The relationship of these indicators is complete, inverse, functional and allows us to evaluate the usefulness of hemodynamic compensation of respiratory function.

These compensation ratios exist up to certain boundary states of the UI (for men up to 30 ml / m 2 , for women up to 28 ml / m 2 ). Following this, partial or incomplete hemodynamic compensation for impaired respiratory function occurs. This is the beginning of the development of the so-called “pulmonary heart” – a condition classified as heart failure with an increase in the minute volume of blood circulation. The CDI indicator, due to its origin of the IRGT, deserves special consideration. The coefficient of respiratory changes in stroke volume is the ratio of the maximum value of the stroke volume to the minimum for one breathing cycle and is normally a very stable value. In healthy people, this figure is in the range of 1.14-1.24 (average value of 1.19) and does not go beyond the value of 1.30, i.e. normally, respiratory changes in stroke volume do not exceed 30%. CDI is mainly due to differences in intrathoracic pressure,affecting the venous return to the right heart, and accordingly — even with the next heartbeat — to the filling of the left ventricle. Undoubtedly, respiratory changes in the vagus nerve tone also matter, however, the Frank-Starling mechanism — changes in ventricular filling — is the leading link in changes in stroke volume during breathing. An increase in KDI reflects a violation of the mechanics of respiration, especially the distensibility of the lungs. The mechanism for increasing CDI in heart failure is the same. It is known that with the earliest forms of heart failureThe Frank-Starling mechanism — changes in ventricular filling — is the leading link in changes in stroke volume during breathing. An increase in KDI reflects a violation of the mechanics of respiration, especially the distensibility of the lungs. The mechanism for increasing CDI in heart failure is the same. It is known that with the earliest forms of heart failureThe Frank-Starling mechanism — changes in ventricular filling — is the leading link in changes in stroke volume during breathing. An increase in KDI reflects a violation of the mechanics of respiration, especially lung distensibility. The mechanism for increasing CDI in heart failure is the same. It is known that with the earliest forms of heart failure lung compliance changes. Therefore, an increase in CDI is a reliable sign of impaired lung function (pulmonary, cardiac, or mixed).

No less valuable is the possibility of quantitative assessment of systemic arterial tone by the method of ITGT. The basis for such a quantitative assessment is the coefficient S / D, where C is the duration of the cardiac cycle, D is the duration of the cataclys of IRGT. Coefficient S / D is included in the formula for calculating EA from IRGT. The integral rheogram is a volume sphygmogram of the entire arterial system as a whole. Therefore, the pinnacle of anacrot is the point in time from the beginning of the expulsion of blood from the left ventricle, which has the largest increase in blood volume in the entire arterial system. Naturally, the higher the elastic resistance of blood vessels to stretching, the shorter the anacrotic rise will be and vice versa. Therefore, the C / D coefficient acquires an independent value of the dynamic indicator, which is proved by the analysis of numerous materials.The reciprocal value of C / D multiplied by 100, called the integral tonicity factor (KIT), makes it possible to estimate the elastic resistance of the vessels (including the small arterial link) in integers, directly proportional to the systemic arterial Nomu tone . The latter circumstance makes it possible to classify tonic reactions by CIT. The KIT value is 55–, corresponds to the extreme state and characterizes the collapse. 65 to 70 — hypotonia, precollaptoid states. From 70 to 80 – moderate (load) reactions. 80—85 — hypertension, centralization of blood circulation. Limiting centralization, violations of the patency of blood vessels are characterized by the values ​​of KIT 85 —92. The rest rate of the integral tonicity coefficient is 73 —77 conventional units.