RU2499557C1 - Method of estimating volume-regulating function of kidneys in conditions of higher pressure of gaseous medium - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, and can be used in case if it is necessary to estimate volume-regulating function of kidneys in diver in conditions of impact of higher gaseous medium pressure. For this purpose diver is placed into pressure chamber with its further submergence to 60-metre depth for 1.5 hours. Loading with 0.5% sodium chloride solution in dose 0.5% of body weight is performed under said conditions. Quantity of sodium, potassium and chlorine, excreted with urine, is determined at 40-th, 60-th and 90-th minute. Obtained indices are used to calculate volume-regulating kidney activity index (VKAI) by formula: VKAI=-3.32+0.18·S₁-0.36·P+0.14·U+0.3·C₁+0.14·S₂+0.11·C₂, where: S₁ is amount of sodium, excreted by kidneys at 40-th minute after salt loading, mmol/hour; P is amount of potassium, excreted at 60-th minute after salt loading, ml/min; U is amount of urine, excreted at 60-th minute after salt loading, ml/min; C₁ is of chlorine, excreted by kidneys at 60-th minute after salt loading, mmol/hour; S₂ is amount of sodium, excreted by kidneys at 90-th minute after salt loading, mmol/hour; C₁ is of chlorine, excreted at 90-th minute after salt loading, mmol/hour. If value of obtained index is lower than 0, volume-regulating function of kidneys is considered to be unsatisfactory. If value is from 0 to 1.1, it is considered to be satisfactory. If value is higher than 1.1, volume-regulating function of kidneys is considered to be good.

EFFECT: method ensures adequate highly accurate estimation of volume-regulating function of kidneys in conditions most closely copying divers' working conditions.

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Description

The invention relates to medicine, in particular to the field of marine medicine, can be used in the practice of diving medicine to assess the volume-regulating function of human kidneys under conditions of exposure to high pressure of the gas environment, by evaluating clinical data.

The volume control system provides for the regulation of the volume of extracellular body fluids, and the kidneys, various departments of the nephron and their blood supply apparatus take part in changing the allocation of water and salts, if necessary, to correct the volume of intravascular fluid

All of the above predetermined the development of this sample by various authors. Thus, methods are known for assessing the volume-regulating function of human kidneys (using a sample loaded with sodium chloride) when examining the possibilities of osmoregulating kidney systems in clinical and experimental conditions (Ryabov S.I. Diagnosis of kidney diseases / S.I. Ryabov, Yu.V. Natochin , B. B. Bondarenko - L .: Medicine, 1979. - 255 p .; A. Gozhenko. The influence of osmotic loads on the functional state of the kidneys of healthy people / A. I. Gozhenko, S. I. Dolomatov, P. A. Shumilova, E.A. Ax, V.A. Pyatenko, I.Yu. Badin // Nephrology. - 2004. - T.8, No. 2. - P.44-48 .; Dongak A.O. Vli osmotic loads on the functional state of the kidneys of healthy people / A.O. Dongak, G.A. Koroshchenko, S.I. Kirsanov, S.G. Krivoshchekov, R.I. Aizman // Bulletin SB RAMS. - 2008. - № 4 (132). - P.77-84.), When examining the crews of spaceships (I. Balakhovsky. Influence of water and water-salt loads in healthy people on orthostatic reactions / I. S. Balakhovsky, I. G. Dlusskaya // Human physiology. - 1981. - T.7, No. 1. - S.130-137.), As well as before and after exposure to increased pressure of the gaseous medium (Kushnirenko N.P. Changes in the functional state of the kidneys with asymptomatic decompression gas formation and decompression sickness (experimental and clinical research): abstract of diss. ... cand. medical sciences / N.P. Kushnirenko - L., VMAA, 1980. - 16 p .; Raymond LW In the weight loss of hiperbaric habitation a disorder of osmoregulation? / LW Raymond, NS Raymond, VP Frattali // Aviat. Space . Environ. Med. - 1980. - Vol. 51, No. 4. - P.397-401). In addition, there is a method for evaluating the excretory and concentration functions of human kidneys under conditions of increased pressure of the gaseous medium (Pat. 2423703 Russian Federation, A. A. Myasnikov, A. Yu. Shitov; No. 2010101343/15; claimed 18.01.2010; publ. 07/10/2011 // Inventions. Utility models: official bulletin - Moscow: FIPS, 2011. - No. 19). At the same time, there are currently no adequate methods for assessing the volume-regulating functions of human kidneys under conditions of increased pressure of the gaseous medium (under pressure chamber conditions).

A disadvantage of the known methods is the low accuracy of the study, as well as the fact that they were used mainly before and after (and not during) exposure to high pressure gas environment.

The aim of the invention is to improve the accuracy of the study of volume-regulating kidney function of specialists working in conditions of altered pressure of the gas and water environment.

The goal is achieved by using a method for evaluating the volume-regulating functions of the kidneys under conditions of increased pressure of the gaseous medium, by evaluating the clinical data obtained after an oral salt load of 0.5% sodium chloride solution, carried out while immersing in a pressure chamber to a depth of 60 meters and being there within 1.5 hours at a dose of 0.5% of body weight, characterized in that they determine the volume-regulating activity index of the kidneys (IVAP) according to the formula:

IVAP = -3.32 + 0.18 · H ₁ -0.36 · K + 0.14 · D + 0.3 · X ₁ + 0.14 · N ₂ + 0.11 · X ₂

Where:

H ₁ - the amount of sodium excreted by the kidneys at 40 minutes after salt loading, mmol / hour;

K is the amount of potassium released at 60 minutes after salt loading, ml / min;

D is the amount of urine excreted at 60 minutes after salt loading, ml / min;

X ₁ - the amount of chlorine excreted by the kidneys at 60 minutes after salt loading, mmol / hour;

H ₂ - the amount of sodium excreted by the kidneys at 90 minutes after salt loading, mmol / hour;

X ₂ - the amount of chlorine released at 90 minutes after salt loading, mmol / hour;

and with its value less than 0, the volume-regulating function of the kidneys is considered unsatisfactory, with a value from 0 to 1.1 - satisfactory and more than 1.1 - the volume-regulating function of the kidneys is considered good.

The method is implemented as follows:

a method is used to evaluate the volume-regulating functions of the kidneys under conditions of increased pressure of the gaseous medium, by evaluating the clinical data obtained after oral salt loading with a 0.5% sodium chloride solution, carried out while immersing in a pressure chamber to a depth of 60 meters and staying there for 1.5 hours at a dose of 0.5% of body weight, characterized in that they determine the index of volume-regulating activity of the kidneys (IVAN) according to the formula:

IVAP = -3.32 + 0.18 · H ₁ -0.36 · K + 0.14 · D + 0.3 · X ₁ + 0.14 · N ₂ + 0.11 · X ₂

Where:

H ₁ - the amount of sodium excreted by the kidneys at 40 minutes after salt loading, mmol / hour;

K is the amount of potassium released at 60 minutes after salt loading, ml / min;

D is the amount of urine excreted at 60 minutes after salt loading, ml / min;

X ₁ - the amount of chlorine excreted by the kidneys at 60 minutes after salt loading, mmol / hour;

H ₂ - the amount of sodium excreted by the kidneys at 90 minutes after salt loading, mmol / hour;

X ₂ - the amount of chlorine released at 90 minutes after salt loading, mmol / hour;

and with its value less than 0, the volume-regulating function of the kidneys is considered unsatisfactory, with a value from 0 to 1.1 - satisfactory and more than 1.1 - the volume-regulating function of the kidneys is considered good.

The methodology for loading sodium chloride, collecting and analyzing urine excretion should be as follows: the test subjects do not take water and food from 20 hours on the previous day before the test. While immersing in a pressure chamber to a depth of 60 meters and staying there for 1.5 hours, sodium chloride (0.5% solution) at room temperature (at a dose of 0.5% of body weight) is taken for 15-20 minutes. Urine is collected by random urination at 40, 60, and 90 minutes after loading with sodium chloride. In this case, the amount of urine excreted, as well as the concentration of electrolytes in it (sodium, potassium, chloride), is determined.

For example, it is necessary to evaluate the volume-regulating function of the kidneys of a diver with a body weight of 60 kg under conditions of exposure to high pressure of the gas environment. For this, a diver is placed in a pressure chamber, immersed to a depth of 60 meters and a load of sodium chloride is carried out at a dose of 0.5% of body weight (in this case 300 ml) of a 0.5% sodium chloride solution. At 40, 60 and 90 minutes after loading with sodium chloride, urine is collected. When evaluating clinical data, the following results were obtained: the amount of sodium excreted by the kidneys at 40 minutes after a water load of 5.25 mmol / hour; the amount of potassium excreted by the kidneys at 60 minutes after a water load of 4.22 mmol / hour; the amount of urine excreted at 60 minutes after a water load of 3.18 ml / min; the amount of chlorine released by the kidneys at 60 minutes after a water load of 6.92 mmol / hour; the amount of sodium excreted by the kidneys at 90 minutes after a water load of 3.53 mmol / hour; the amount of chlorine released at 90 minutes after a water load of 7.21 mmol / hour. Applying the formula, we calculate the volume-regulating activity index of the kidneys (IVAP):

IVAP = -3.32 + 0.18 5.25-0.36 4.22 + 0.14 3.18 +

0.3 · 6.92 + 0.14 · 3.53 + 0.11 · 7.21

IVAP = -3.32 + 0.945-1.51 + 0.445 +

2.076 + 0.492 + 0.793

ICAP = -0.079

Consequently, IVAP will, in this case, be less than 0 therefore, the volume-regulating function of the kidneys of such a diver under conditions of increased pressure of the gaseous medium should be considered unsatisfactory.

For example, it is necessary to evaluate the volume-regulating function of the kidneys of a diver with a body weight of 80 kg under the conditions of exposure to high pressure of the gas medium. For this, a diver is placed in a pressure chamber, immersed to a depth of 60 meters and a load is carried out with sodium chloride at a dose of 0.5% of body weight (in this case 400 ml) of a 0.5% sodium chloride solution. At 40, 60 and 90 minutes after loading with sodium chloride, urine is collected. When evaluating clinical data, the following results were obtained: the amount of sodium excreted by the kidneys at 40 minutes after a water load of 7.52 mmol / hour; the amount of potassium excreted by the kidneys at 60 minutes after a water load of 4.17 mmol / hour; the amount of urine excreted at 60 minutes after a water load of 3.27 ml / min; the amount of chlorine released by the kidneys at 60 minutes after a water load of 7.54 mmol / hour; the amount of sodium excreted by the kidneys at 90 minutes after a water load of 4.23 mmol / hour; the amount of chlorine released at 90 minutes after a water load of 8.41 mmol / hour. Applying the formula, we calculate the volume-regulating activity index of the kidneys (IVAP):

IVAP = -3.32 + 0.18 · 7.52-0.36 · 4.17 + 0.14 · 3.27 +

0.3 · 7.54 + 0.14 · 4.23 + 0.11 · 8.41

IVAP = -3.32 + 1.356-1.5012 + 0.4578 + 2.262 + 0.5922 + 0.9251

ICAP = 0.7695

Therefore, IVAP will, in this case, be more than 0, but less than 1.1, therefore, the volume-regulating function of the kidneys of such a diver under conditions of increased pressure of the gaseous medium should be considered satisfactory.

For example, it is necessary to evaluate the volume-regulating function of the kidneys of a diver with a body weight of 90 kg under conditions of exposure to increased pressure of the gas medium. For this, a diver is placed in a pressure chamber, immersed to a depth of 60 meters and a load is carried out with sodium chloride at a dose of 0.5% of body weight (in this case 450 ml) of a 0.5% sodium chloride solution. At 40, 60 and 90 minutes after loading with sodium chloride, urine is collected. When evaluating clinical data, the following results were obtained: the amount of sodium excreted by the kidneys at 40 minutes after a water load of 7.65 mmol / hour; the amount of potassium excreted by the kidneys at 60 minutes after a water load of 4.31 mmol / hour; the amount of urine excreted at 60 minutes after a water load of 4.23 ml / min; the amount of chlorine released by the kidneys at 60 minutes after a water load of 8.31 mmol / hour; the amount of sodium excreted by the kidneys at 90 minutes after a water load of 4.82 mmol / hour; the amount of chlorine released at 90 minutes after a water load of 9.26 mmol / hour. Applying the formula, we calculate the volume-regulating activity index of the kidneys (IVAP):

IVAP = -3.32 + 0.18 · 7.65-0.36 · 4.31 + 0.14 · 4.23 +

0.3 · 8.31 + 0.14 · 4.82 + 0.11 · 9.26

IVAP = -3.32 + 1.377-1.551 + 0.592 +

2.493 + 0.6748 + 1.0186

IVAP = 1.28

Therefore, IVAP will, in this case, be more than 1.1, therefore, the volume-regulating function of the kidneys of such a diver under conditions of increased pressure of the gaseous medium should be considered good.

Our studies with the participation of 37 volunteer test subjects confirm the effectiveness and validity of the method we use. The results of these studies provide detailed specific results.

So, when examining 37 volunteer subjects in this way, we obtained data indicating that 13.5% of the examined (5 people) showed unsatisfactory potassium kidney function, 67.5% of the examined (25 people) had satisfactory, and 19% (7 people) - good excretory and concentration function of the kidneys under conditions of exposure to high pressure of the gas environment.

Moreover, if we compare our survey results with the data presented in the work of N.P. Kushnirenko (Kushnirenko N.P. Changes in the functional state of the kidneys during asymptomatic decompression gas formation and decompression sickness (experimental and clinical research): abstract of diss. ... cand. medical sciences / N.P. Kushnirenko - L., VMedA, 1980. - 16 pp.), it turns out that in this work only excretory function of the kidneys was determined (only the amount of urine excreted, but not its electrolyte composition) was determined, but expl vanie conducted before and after (not during) the impact of high pressure gas environment, which reduces the accuracy of the study. Nevertheless, the author obtained results similar to ours when examining 33 divers (test subjects), which showed that 4 of them (12.1%) showed impaired renal function of the kidneys, and the rest 29 people (87.9 %) such violations were not detected.

It follows from this that when using the method we are offering, the accuracy of determining the functions of the kidneys is increased, namely, the number of persons with detected violations of the volume-regulating function of the kidneys is increased. In the studies of N.P. Kushnirenko of such individuals - 12.1%, and in our studies of such subjects - 13.5%. In addition, in our studies, 67.5% of the examined (25 people) showed satisfactory volume-regulating renal function, which is a transition between good and unsatisfactory potassium-kidney function. This suggests a more accurate identification of individuals with different volume-regulating kidney function using our proposed method.

Thus, by evaluating the clinical data obtained after the salt load carried out during compression (immersion in the pressure chamber), the person providing medical support for diving descents can accurately determine the volume-regulating function of the human kidneys under conditions of increased pressure of the gas environment, which determines the industrial applicability of this method in healthcare.

Claims (1)

A method for assessing volume-regulating kidney functions under conditions of increased pressure of the gaseous medium by evaluating the clinical data obtained after oral salt loading with a 0.5% sodium chloride solution, carried out while immersing in a pressure chamber to a depth of 60 m and being there for 1.5 h in a dose of 0.5% of body weight, characterized in that they determine the index of volume-regulating activity of the kidneys (IVAP) according to the formula:
IVAP = -3.32 + 0.18 · H ₁ -0.36 · K + 0.14 · D + 0.3 · X ₁ + 0.14 · N ₂ + 0.11 · X ₂ ,
where H ₁ - the amount of sodium excreted by the kidneys at 40 minutes after salt loading, mmol / h;
K is the amount of potassium released at 60 minutes after salt loading, ml / min;
D is the amount of urine excreted at 60 minutes after salt loading, ml / min;
X ₁ - the amount of chlorine excreted by the kidneys at 60 minutes after salt loading, mmol / h;
N ₂ - the amount of sodium excreted by the kidneys at 90 minutes after salt loading, mmol / h;
X ₂ - the amount of chlorine released at 90 minutes after salt loading, mmol / h;
and with its value less than 0, the volume-regulating function of the kidneys is considered unsatisfactory, with a value from 0 to 1.1 - satisfactory and more than 1.1 - the volume-regulating function of the kidneys is considered good.