RU2446745C2 - Method of estimating dopplerographic indices of renal blood flow in children and teenagers - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to pediatrics, children's nephrology and urology, and is intended for estimation of dopplerographic indices of renal blood flow in children and teenagers. During ultrasonic dopplerography of kidneys determined are: maximal systolic rate of blood flow - MCR (cm/s), final diastolic rate - FDR (cm/s) and index of resistance (IR) by formula: MCR-FDR/MSR at the level of main renal artery - 1 level, segmental - 2 level, interlobar - 3 level and arch - 4 level of kidney artery. If MSR value is from 81.8 to 122.5 cm/s - 1 level, 43.8-84.4 cm/s - 2 level, 17.5-40.0 cm/s - 3 level and 11.2-16.4 cm/s - 4 level; FDR from 23.5 to 56.2 cm/s - 1 level, 9.1-32.4 cm/s - 2 level, 6.7-16.5 cm/s - 3 level and 3.1-10.6 cm/s - 4 level and IR from 0.59 to 0.69 - 1 level, 0.50-0.72 - 2 level, 0.52-0.68 - 3 level and 0.49-0.64 - 4 level renal blood flow is estimated as normal to adequately functioning kidney. If MSR is higher than 122.5 cm/s - 1 level and FDR is higher than 56.2 cm/s - 1 level diagnosed is increase of perfusion in kidney, and if MSR is lower than 81.8 cm/s - 1 level and FSR is lower than 23.5 cm/s - 1 level reduction of perfusion in kidney. If IP is higher than 0.69 - 1 level, 0.72 - 2 level, 0.68 - 3 level and 0.64 - 4 level increase of peripheral resistance in form of vasospasm is diagnosed; id IP reduction is less than 0.59 - 1 level, 0.50 - 2 level, 0.52 - 3 level and 0.49 - 4 level diagnosed is pathologic reaction of vascular wall of microcirculatory way arteries in form of its rigidity.

EFFECT: method makes it possible to increase accuracy of estimation of hemodynamic disturbances in kidneys in children and teenagers.

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Description

The invention relates to medicine, namely to pediatrics, pediatric nephrology and urology.

Renal function is largely determined by the effectiveness of blood circulation in their vascular pool. Disorders of renal hemodynamics occur both with difficulty in the outflow of blood from the organ, and in violation of its flow. The structure of the kidneys and their arterial bed under disease conditions is one of the most important sections of nephrology and urology, which is associated with the high prevalence of this pathological condition in childhood and adolescence. The rate of progression of renal dysfunction is directly proportional to the degree of hemodynamic disturbances in them. In addition to the classic signs of kidney damage characterizing nephrosclerosis (oligoanuria, an increase in plasma creatinine, urea, a decrease in glomerular filtration rate according to DRG with glomerulotropic radiopharmaceutical, anemia, decompensated metabolic acidosis, delayed physical development, arterial hypertension), currently there is a lot of attention paid to indicators , reflecting the preclinical stage of nephropathy, which include, in particular, the state of intrarenal hemodynamics. Currently, an informative way to assess the state of renal hemodynamics is dopplerometry. Carrying out with its help a qualitative and quantitative assessment of blood flow in all vessels of the kidney, indirectly, it is possible to evaluate the functional safety of the renal parenchyma, the nature of the pathological process, its prognosis and the effectiveness of the therapy.

The development of sclerotic changes in the kidneys as a result of the pathological process is accompanied by the regular involvement of intrarenal vessels. The formation of arteriosclerosis, progressive elastofibrosis of the arteries, the occurrence of proliferative endarteritis, as well as perivascular sclerosis lead to a change in vascular architectonics. In deformed vessels, blood flow becomes turbulent, depending on its shape and severity, its speed and resistive parameters change.

The study of the diagnosis of normal and pathological renal blood flow has been the subject of many works in the 90s of the XX century and the first decade of the XI century, but it remains relevant at the present time. There are various methods for assessing hemodynamic disorders in the kidneys in children: dynamic renoscintigraphy, radiopaque methods for examining the urinary tract, renal angiography, CT angiography, MRI angiography, but ultrasound dopplerography currently holds the leading place in the diagnosis of blood circulation disorders due to its high Doppler ultrasound informativeness, non-invasiveness, relative cheapness, the possibility of repeated use, the absence of an ionizing load on the patient, which is especially important in pediatric practice. Ultrasound duplex scanning is based on a qualitative (assessment of the degree of vascularization) and quantitative (registration of Doppler ultrasound) blood flow estimates.

Currently, there are numerous publications in domestic and foreign literature on the study of renal hemodynamics in children and adults with various pathological conditions. A known method for assessing the progression of chronic renal failure in glomerulonephritis and pyelonephritis in children by ultrasound dopplerographic examination of the kidneys. Vascular blood flow is estimated at the level of interlobular arteries according to the average blood flow velocity and, depending on its values, the onset of chronic renal failure is determined (patent RU 2218870, IPC АВВ 8/06, published on December 20, 2003). This method allows you to diagnose the disease only at the level of the interlobular arteries of the kidneys and only one dopplerographic indicator, not allowing to judge the violations of renal hemodynamics throughout the organ.

A known method for the diagnosis of nephroangiopathy is described in patent RU 2289320, IPC A61B 8/06, publ. 12.20.2006, Renal blood flow was assessed at all levels of the arterial tree of the kidney with the determination of the maximum systolic, final diastolic rates and resistance index for various diseases of the urinary system. Four types of renal hemodynamic disturbances were found, but without assessing the degree of deviation of Dopplerographic parameters.

There is also a method for detecting renal vascular lesions in children and adolescents with diabetic nephroangiopathy, consisting in determining the resistance index in the renal arteries by the Doppler method before and after loading with meat broth, and the development of nephroangiosclerosis is determined by increasing the index rise above 0.73 (patent RU 2359615, IPC А61В 8/06, published on June 27, 2009). This method of assessment (diagnosis) allows you to determine only severe violations of the hemodynamics of the kidneys with the development of chronic renal failure and does not allow to diagnose the initial manifestations of nephroangiopathy.

As a result of a patent information search, the closest analogue of the claimed technical solution was not identified.

The technical result of the claimed invention is to improve the accuracy of the assessment of hemodynamic disorders in the kidneys in children and adolescents. The method is based on the calculation of the values of dopplerographic parameters with unchanged hemodynamics in the kidneys and with various degrees of circulatory disorders.

A method for assessing Doppler ultrasound parameters of renal blood flow in children and adolescents is presented, which consists in determining, during ultrasound dopplerography of the kidneys, the maximum systolic blood flow velocity - MSS (cm / s), the final diastolic velocity - CDS (cm / s) and resistance index (IR) according to the formula: MSS-KDS / MSS at the level of the main renal artery (level 1), segmental (level 2), interlobar (level 3) and arc (level 4) kidney arteries, with a value of MSS from 81.8 to 122.5 cm / s ( 1 level), 43.8-84.4 cm / s (2 level), 17.5-40.0 cm / s (3 level) and 11.2- 16.4 cm / s (4 level); KDS from 23.5 to 56.2 cm / s (1 level), 9.1-32.4 cm / s (2 level), 6.7-16.5 cm / s (3 level) and 3.1 -10.6 cm / s (level 4) and IR from 0.59 to 0.69 (level 1), 0.50-0.72 (level 2), 0.52-0.68 (level 3) and 0.49-0.64 (level 4), renal blood flow is assessed as normal to an adequately functioning kidney, with MSS above 122.5 cm / s (level 1) and CDS above 56.2 cm / s (level 1), they diagnose an increase in perfusion in the kidney, and with MSS less than 81.8 cm / s (level 1) and CDS less than 23.5 cm / s, a decrease in perfusion in the kidney is diagnosed, with IR over 0.69 (level 1), 0.72 (level 2) , 0.68 (level 3) and 0.64 (level 4) diagnose an increase in peripheral th resistance as vasospasm; with a decrease in IR less than 0.59 (1 level), 0.50 (2 level), 0.52 (3 level) and 0.49 (4 level), a pathological reaction of the vascular wall of the arteries of the microvasculature is diagnosed in the form of its rigidity.

The essence of the invention lies in nonparametric statistical analysis - a centile method for assessing dopplerographic indicators in children and adolescents. The centile series method is based on the principle of variability, which takes into account the percentage distribution of the frequency of occurrence of the magnitude of this attribute. Moreover, for each studied level of renal blood flow, centile intervals (“corridors”) are distinguished. 50% of all values of the analyzed sample are taken as the norm - indicators ranging from the 25th to the 75th centile. Values below typical are distributed at centile intervals as follows: the 1st corridor includes data on the centile probability of 3% (very low), the 2nd corridor includes values between the 3rd 10th centile (low), 3rd the interval includes indicators between 10 and 25 centile boundaries (reduced). Correspondingly, values that exceed average values are distributed: the 6th interval includes indicators between 75 and 90 centiles (increased), high indicators will be in the range of 90-97 centile probabilities, and the 8th interval includes values after 97 centiles - very high. Thus, zones below the 10th and above the 90th centile indicate a pronounced decrease or, accordingly, an increase in the measured trait (Dopplerographic indicator). Centile intervals and their assessment:

to the 3rd centile - “very low” level (3%);

from the 3rd to the 10th centile - “low” level (7%);

from the 10th to the 25th centile - the level is “below average” (15%);

from the 25th to the 75th centile - the “average” level (50%);

from the 75th to the 90th centile - the level is "above average" (15%);

from the 90th to the 97th centile - “high” level (7%);

from the 97th centile - a "very high" level (3%).

At the same time, 15% of children will have indicators “above average” or “below average”, 7% - “low” or “high” and 3% - “very low” or “very high”.

Ultrasound duplex scanning of the kidneys was performed for 418 children and adolescents (group I of children) aged 3 to 17 years (boys 256, average age 10.3 ± 3.4 years and girls 162, average age 11.8 ± 2.7 years ), which belonged to the I and II health groups; in the first group, children excluded congenital and acquired kidney diseases, all children in this group had blood and urine tests without pathological changes. The second group included 397 children and adolescents with chronic inflammatory diseases (59 children with tubulointerstitial nephritis and 37 children with chronic glomerulonephritis and 295 children with chronic secondary pyelonephritis against a urological pathology) of the urinary system. The age of children in the second group was recorded from 3 to 17 years: boys 204, average age 8.3 ± 4.6 years and girls 193, average age 11.2 ± 2.3 years). Children with chronic kidney diseases had pathological changes in blood and urine tests, characteristic of the nosological form with varying degrees of impaired renal function.

All children underwent duplex scanning of the kidneys at the level of the main renal artery (level 1), segmental arteries (level 2), interlobar arteries (level 3) and lobular arteries of the kidney (level 4). Quantitative Dopplerographic indicators were calculated: maximum systolic velocity - MSS (cm / s), final diastolic velocity - KDS (cm / s) and resistance index (IR) as the ratio of the difference between MSS and KDS to MSS of renal blood flow.

The analysis performed by the authors showed that all Dopplerographic indicators were the same in boys and girls and did not have significant differences (p <0.001) between the ages of 3 and 17 years and therefore can be used in children of different sexes older than 3 years.

Table 1 DISTRIBUTION OF THE MAXIMUM SISTOLIC SPEED (CM / S) BY THE LEVEL OF MEASUREMENT OF THE ARTERIAL BLOOD IN THE KIDNEY RENAL BLOOD LEVEL CENTILES 3 10 25 fifty 75 90 97 BASIC ARTERY - 1 lvl 52.6 73,2 81.8 91.4 122.5 149.8 166.1 SEGMENTARY ARTERIES - 2 lvl 29.5 35,4 43.8 65.8 84,4 91.3 112.1 INTERLOCK ARTERIES - 3 lvl 9.9 13.7 17.5 31,2 40,0 44.7 58.6 ARC ARTERIES - 4 lvl. 4.2 9.6 11,2 14.3 16,4 19.3 27.9

table 2 DISTRIBUTION OF FINAL DIASTOLIC SPEED (CM / S) BY THE LEVEL OF MEASUREMENT OF ARTERIAL BLOOD IN THE KIDNEY LEVEL CENTILES KIDNEY BLOOD 3 10 25 fifty 75 90 97 BASIC ARTERY - 1 lvl 14.5 17.6 23.5 36.7 56.2 80.7 92.4 SEGMENTARY ARTERIES - 2 lvl 0.4 4.8 9.1 15.7 32,4 41.7 47.2 INTERLOCK ARTERIES - 3 lvl 0,0 4.1 6.7 11.0 16.5 19.7 22.3 ARC ARTERIES - 4 lvl. 0,0 1,2 3,1 5.1 10.6 12,4 14.7

Table 3 DISTRIBUTION OF RESISTANCE INDEX VALUES BY THE LEVEL OF MEASUREMENT OF ARTERIAL BLOOD IN THE KIDNEY RENAL BLOOD LEVEL CENTILES 3 10 25 fifty 75 90 97 BASIC ARTERY - 1 lvl 0.51 0.55 0.59 0.64 0.69 0.79 0.89 SEGMENTARY ARTERIES - 2 lvl 0.42 0.44 0.50 0.68 0.72 0.87 0.95 INTERLOCK ARTERIES - 3 lvl 0.41 0.42 0.52 0.61 0.68 0.76 0.84 ARC ARTERIES - 4 lvl. 0.34 0.41 0.49 0.58 0.64 0.67 0.76

Scheme for assessing hemodynamic disorders of renal blood flow in children and adolescents.

With a combined assessment of the maximum systolic velocity, final diastolic blood flow velocity and resistance index at all levels of the arterial tree of the kidney, the following scheme can conditionally be applied, in which practically all variants of Dopplerographic indicators fit:

Normal hemodynamic parameters - the position of the parameters MCC, CDS and IR from 25 to 75 centiles. We found that in the range of average values of Dopplerographic indicators there are no significant changes and correlations with impaired renal function and the severity of inflammatory changes (r = 0.14, p <0.01).

Renal hemodynamic disorders:

1. Increased MSS and CDS - the position of the parameters in the zone of 75-90 centiles is characterized by a 1 degree increase in speed indicators of renal blood flow (perfusion), a relationship with the ESR and leukocyturia during the exacerbation of chronic inflammatory diseases (r = 0.54 p <0, 05 and r = 0.57 p <0.05, respectively).

2. Increased MSS and CDS - the position of the parameters in the area of more than 90 centiles is characterized by a 2 degree increase in the rate of renal blood flow (perfusion), a relationship is found with the ESR and leukocyturia during the exacerbation of chronic inflammatory diseases (r = 0.87 p <0.05 and r = 0.76 p <0.05).

3. The decrease in MSS and CDS - the position of the parameters in the zone of 10-25 centiles is characterized by a 1 degree decrease in the rate of renal blood flow (perfusion), a relationship with the glomerular filtration rate (r = 0.53 p <0.05), with the level of proteinuria ( r = -0.56 p <0.05) and the contribution of the affected kidney to the cumulative function according to the DRG (r = 0.57 p <0.009).

4. The decrease in MSS and CDS - the position of the parameters in the zone of less than 10 centiles is characterized by a 2 degree decrease in the rate of renal blood flow (perfusion), a relationship with the glomerular filtration rate (r = 0.81 p <0.05), with the level of proteinuria (r = -0.60 p <0.05) and the contribution of the affected kidney to the cumulative function according to the DRG (r = 0.94 p <0.009).

5. An increase in peripheral resistance - IR, the position of the parameter in the zone of 75 or more centiles characterizes the violation of microcirculation in the kidney, spasm of the arteries, increased tone of the arteries and arterioles, which leads to ischemia of the renal parenchyma and the development of irreversible changes - nephrosclerosis. A relationship was found between IR and glomerular filtration rate (r = -0.41 p <0.05), with proteinuria level (r = 0.73 p <0.05) and the contribution of the affected kidney to the cumulative function according to DRG (r = -0.85 p <0.009).

6. Decrease in peripheral resistance - IR, the position of the parameter in the zone of less than 25 centiles characterizes the violation of microcirculation in the kidney to the degree of decompensation of the regulation mechanisms of the intrarenal blood flow and is expressed in hypoperfusion, which inevitably leads to tissue hypoxia, ischemia of all structural elements of the kidney and, as a result, development nephrosclerosis. The decrease in peripheral resistance is explained by the inclusion of mechanisms of arteriovenous shunting at the juxtamedullary level (Truet's shunt), which ensure that most of the blood flowing through the trunk of the renal artery, bypassing the cortical substance, enters the venous system. The lack of adequate blood flow in the cortical substance further aggravates ischemia and the progression of the disease is accompanied by the formation of glomerulosclerosis and tubulointerstitial fibrosis. The absence of blood flow in the cortical layer of the renal parenchyma was detected in patients diagnosed with 0-I-II degrees of chronic renal failure.

TABLE 4 DIAGRAM OF THE DOPPLEROGRAPHIC INDICATORS OF RENAL HEMODYNAMICS RESISTANCE INDEX CENTILES CENTILIES OF SPEED INDICATORS OF BLEED 3-10 10-25 25-75 75-90 90-97 3-10 REDUCED PERFUSION 2 Tbsp. SIGNS OF RIGIDITY OF THE VASCULAR WALL 2 ART. REDUCED PERFUSION 1 Tbsp. SIGNS OF RIGIDITY OF THE VASCULAR WALL 2 ART. SIGNS OF JUKSTAMEDULLARY SHUNTING SIGNS OF RIGIDITY OF VASCULAR WALL 2 ART. IMPROVEMENT OF PERFUSION 1 ST. SIGNS OF RIGIDITY OF THE VASCULAR WALL 2 ART. IMPROVEMENT OF PERFUSION 2 Tbsp. SIGNS OF RIGIDITY OF THE VASCULAR WALL 2 ART. 10-25 REDUCED PERFUSION 2 Tbsp. SIGNS OF RIGIDITY REDUCED PERFUSION 1 Tbsp. SIGNS SIGNS OF RIGIDITY OF THE VASCULAR WALL 1 ST. IMPROVEMENT OF PERFUSION 1 ST. SIGNS IMPROVEMENT OF PERFUSION 2 Tbsp. SIGNS

VASCULAR WALL 1 ST. RIGIDITY OF THE VASCULAR WALL 1 ST. RIGIDITY OF THE VASCULAR WALL 1 ST. RIGIDITY OF THE VASCULAR WALL 1 ST. 25-75 REDUCED PERFUSION 2 Tbsp. REDUCED PERFUSION 1 Tbsp. WITHOUT HEMODYNAMIC VIOLATIONS IMPROVEMENT OF PERFUSION 1 ST. IMPROVEMENT OF PERFUSION 2 Tbsp. 75-90 REDUCED PERFUSION 2 Tbsp. SIGNS OF VASOSPASM 1 ST. REDUCED PERFUSION 1 Tbsp. SIGNS OF VASOSPASM 1 ST. SIGNS OF VASOSPASM 1 ST. IMPROVEMENT OF PERFUSION 1CT. SIGNS OF VASOSPASM 1 ST. IMPROVEMENT OF PERFUSION 2CT. SIGNS OF VASOSPASM 1 ST. 90-97 REDUCED PERFUSION 2 Tbsp. SIGNS OF VASOSPASMA 2 ST. REDUCED PERFUSION 1 Tbsp. SIGNS OF VASOSPASMA 2 ST. SIGNS OF VASOSPASMA 2 ST. IMPROVEMENT OF PERFUSION 1 ST. SIGNS OF VASOSPASMA 2 ST. IMPROVEMENT OF PERFUSION 2 Tbsp. SIGNS OF VASOSPASMA 2 ST.

In support of the information content of the claimed diagnostic criteria, we present clinical examples:

1. Boy Yu., 5 years old, was examined on the first day of hospital stay with a diagnosis of acute glomerulonephritis, nephrotic syndrome. The condition is serious, pale, pronounced peripheral edema, ascites, pulse 92 beats per minute. Blood pressure 120/70 mm Hg Blood test: hemoglobin 132 g / l, leukocytes 12.6 · 10 / l, neutrophilia in the leukocyte formula, ESR 43 mm / h. In biochemical analysis, hypoproteinemia. Urinalysis: specific gravity 1006, protein 0.66 g / l, in the sediment erythrocytes 30-40 in the field of view. Sample according to Zimnitsky: SD - 1160 ml, DD - 440 ml, ND - 720, specific gravity 1002-1010. GFR - 51.6 ml / min. Urine culture - no growth of flora. With an ultrasound examination of the kidneys, a thickening of the parenchyma of the kidneys, an increase in its echogenicity. Dopplerographic indicators: main renal artery (MCC / CDS / IR) - 172/64 / 0.63; segmental arteries - 98/39 / 0.60; interlobar - 51/18 / 0.65; arc arteries - 26/13 / 0.5. According to the proposed criteria, the data obtained correspond to speed indicators above 75 centiles - an increase in perfusion with unchanged peripheral resistance (IR within 25-75 centiles).

2. Girl S., 9 years old, was admitted for examination and treatment to the urology department of MU DKKB No. 9. Within 8 years, there is a diagnosis of Chronic secondary pyelonephritis, a relapsing course. Bilateral mixed vesicoureteral reflux: on the right 4-5 tbsp., On the left - 1-2 degrees, decreased renal function. The state of moderate severity, the skin is pale, decreased appetite, "bruises" under the eyes, rare urination, pulse 68 beats per min. Blood pressure 130/90 mm Hg Blood test: hemoglobin 82 g / l, white blood cells 6.4 · 10 / l, in the white blood cell unchanged, ESR 12 mm / h. In biochemical analysis, plasma creatinine is 0.250 mmol / l, urea is 10.8 mol / l, and total protein is 57 g / l. Urinalysis: specific gravity 1001, protein 1.0 g / l, in the sediment - leukocytes 20-30 in the field of view. Sample according to Zimnitsky: SD - 1310 ml, DD - 520 ml, ND - 790, specific gravity 1001-1008. GFR - 42.3 ml / min. Urine culture - no growth of flora. During ultrasound examination, the right kidney is significantly reduced in size, the contour is not even, connective tissue retraction of the parenchyma, echogenicity of the parenchyma is nonuniformly increased (signs of secondary wrinkling). Dopplerographic indicators: main renal artery (MCC / CDS / IR) - 51/12 / 0.76; segmental arteries - 34/6 / 0.82; interlobar - 12/3 / 0.75; arc arteries - 5/3 / 0.4. According to the proposed criteria, the data obtained correspond to speed indicators below 25 centiles - lower perfusion, peripheral resistance indicators are increased (IR more than 75 centiles), which reflects vasospasm and renal tissue ischemia, and a decrease in peripheral resistance in the renal parenchyma as a reflection of the inclusion of arteriovenous bypass mechanisms ( IR less than 10 centiles). Taking into account the medical history, clinical and laboratory data, and Doppler ultrasound, the development of chronic renal failure was diagnosed.

Thus, the authors proposed method for assessing the degree of hemodynamic disturbances in the kidneys in children and adolescents, based on the calculation of centile corridors of Dopplerographic parameters, is very simple, does not require special preparation for the study, the absence of contraindications, cost-effectiveness, does not depend on the gender and age of children, may be used in screening examinations, allows you to identify both borderline conditions and diagnose lesions in the early stages of the development of the pathological process, which improves hell The adequacy of the treatment measures and improves the quality of the child’s health. The presence of a clear correlation of Dopplerographic indicators with the degree of decrease in renal function makes it possible to use them as criteria for the progression of chronic urinary tract diseases.

Claims (1)

A method for assessing dopplerographic indicators of renal blood flow in children and adolescents, which consists in determining with ultrasound dopplerography of the kidneys the maximum systolic blood flow velocity - MSS (cm / s), the final diastolic velocity - KDS (cm / s) and resistance index (IR) according to the formula: MSS -KDS / MSS at the level of the main renal artery - 1 level, segmental - 2 level, interlobular - 3 level and arc - 4 level of the arteries of the kidney, with an MSS from 81.8 to 122.5 cm / s - 1 level, 43, 8-84.4 cm / s - 2 level, 17.5-40.0 cm / s - 3 level and 11.2-16.4 cm / s - 4 ur a ram; KDS from 23.5 to 56.2 cm / s - 1 level, 9.1-32.4 cm / s - 2 level, 6.7-16.5 cm / s - 3 level and 3.1-10, 6 cm / s - 4 level and IR from 0.59 to 0.69 - 1 level, 0.50-0.72 - 2 level, 0.52-0.68 - 3 level and 0.49-0.64 - level 4 renal blood flow is assessed as normal to an adequately functioning kidney, with MSS above 122.5 cm / s - 1 level and KDS above 56.2 cm / s - 1 level is diagnosed with increased perfusion in the kidney, and with MCC less than 81.8 cm / s - 1 level and CDS less than 23.5 cm / s - 1 level are diagnosed with a decrease in perfusion in the kidney, with IR over 0.69 - 1 level, 0.72 - 2 level, 0.68 - 3 level and 0, 64 - 4 level diagnose an increase in ne peripheral resistance in the form of vasospasm; with a decrease in IR less than 0.59 - 1 level, 0.50 - 2 level, 0.52 - 3 level and 0.49 - 4 level, a pathological reaction of the vascular wall of the arteries of the microvasculature is diagnosed in the form of its rigidity.