RU2547783C2 - Method of traumatic shock diagnostics - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to medicine, namely to diagnostics. Registration of an electrocardiosignal in a patient, which is used to calculate HR and parameters of the left ventricle haemodynamics, is performed. HR value is determined by an original formula. After that AP is calculated on the basis of haemodynamics parameters by an original formula.

EFFECT: method makes it possible to provide the fast diagnostics of traumatic shock within one cardiocycle and increase reliability due to taking into account the haemodynamic parameters.

11 dwg

Description

The present invention relates to medicine and can be used as a quick way to determine the presence of traumatic shock (within one cardiocycle) in various clinical situations. The invention serves to represent the functional state of the patient’s body in real time according to the electrocardiogram.

A known method for the diagnosis of traumatic shock [1] by clinical examination of the patient. This takes into account the nature and location of the injury or injury, condition

- consciousness (from severe anxiety to deep coma);

- skin integument (sharp pallor, cold, moist and sticky to the touch, the subungual bed is pale, often cyanotic);

- diuresis (oliguria or anuria);

- cardiovascular system (pulse is frequent, threadlike, heart sounds are muffled);

- respiratory system (shortness of breath).

The disadvantages of this method are the complexity of its interpretation, the variability of clinical symptoms, the need for clinical experience and knowledge of the examiner, the difficulty of observing the dynamics, in addition, the subjectivity of the assessment of symptoms and the lack of diagnostic capabilities in emergency situations.

Closest to the proposed invention is a method for the diagnosis of traumatic shock [2], which consists in the fact that the patient is determined for the presence of pulse and breathing, in their absence, emergency care is provided, and if breathing is not restored, a lethal outcome is diagnosed, cardiocycle is released when breathing is restored , determination of heart rate, determination of the presence or absence of traumatic shock.

As follows from the description of the known method for the diagnosis of traumatic shock, it is based on the photoplethysmography method, which determines the dependence of the blood supply to a site or body segment on time for one cardiocycle.

According to the authors of the invention, the disadvantages of this method are:

- a big waste of time;

- the complexity of recording photoplethysmograms;

- low measurement accuracy.

The figure 1 shows a diagram of an algorithm that implements a known method for the diagnosis of traumatic shock. The sequence of actions in the known algorithm is as follows:

1 - determination of the condition of the victim;

2 - determination of heart rate;

3 - allocation of a cardiocycle;

4 - obtaining photoplethysmogram;

5 - construction of a photoplethysmatic figure;

6 - determination of blood pressure by photoplethysmatic figure;

7 - determination of the area of the photoplethysmatic figure;

8 - determination of linear functions.

The figure 2 shows an example of a device for recording photoplethysmogram. The plethysmograph includes: plethysmographic receptor (1) for the finger, a tube (2) connecting the air space of the receptor with a mechanoelectric sensor (3) and a calibrator (4), a tap (5) for communicating the air ducts of the plethysmograph with the atmosphere, an amplifier (6) recording device (7).

The figure 3 shows an example of photoplethysmogram obtained during one cardiocycle.

Figure 4 illustrates the construction of a photoplethysmatic figure.

The figure 5 shows an example of determining the area of the photoplethysmographic figure in a planimetric manner.

The figure 6 shows a table with the calculated values of the relative error in determining heart rate in a known method for the diagnosis of traumatic shock.

As follows from the analysis of figure 1 of the known invention, first determine the heart rate (heart rate). Then, according to the obtained heart rate values, the duration of the cardiocycle is determined. These actions are the distinctive features of the known method for the diagnosis of traumatic shock. Since the calculation of heart rate and the selection of the cardiocycle occurs manually, the measurement error will have a value that exceeds the maximum permissible value, which does not allow classifying the measuring instrument as a measuring instrument. It is known that the relative error of the measuring instrument should not exceed δ≤5% (the lowest accuracy class). If this value is exceeded (5%), the measuring instrument turns into an indication means. We show the possible values of the relative error in determining heart rate in a known method for the diagnosis of traumatic shock. In emergency situations in a known method for the diagnosis of traumatic shock, heart rate is determined by the following formula:

$$H\mathrm{FROM}{\mathrm{FROM}}_{\mathrm{and}s\mathrm{at}e\mathrm{from}t}=\mathrm{four}\cdot n_t\left(\mathrm{at}d/m\mathrm{and}n\right)(\mathrm{one})$$

where n _t is the number of heartbeats counted over 15 seconds. The following errors are possible in expression (1):

- in the calculation of the number of heart beats n ± 1;

- in determining the time of counting the number of heart beats t ± 0.5.

.To determine the error in calculating heart rate in a known method for the diagnosis of traumatic shock, it is necessary to analyze the ratio $$\left(\frac{n\pm \mathrm{one}}{t\pm 0.5}\right)$$

.

Table 1 in figure 6 shows the values of the relative error in determining heart rate in a known method for the diagnosis of traumatic shock. The analysis of table 1 shows that the values of the relative error in the determination of heart rate in the known method for diagnosing traumatic shock exceed 5%, which, according to the authors of the present invention, is unacceptable, since the data obtained with this error are then used in the formulas to determine the presence of traumatic shock and can lead to an error.

The basis of the known method for the diagnosis of traumatic shock is the plethysmography method, which, according to the authors of the known invention, allows dynamic monitoring of the condition of the victim non-invasively, cuffless and objectively.

Plethysmography is a diagnostic method for graphically studying the blood supply to tissues in dynamics. The basis of plethysmography is the principle of changing the volume in the measured area due to the dynamic change in the amount of blood: the volume of any organ is the sum of the volume of its constituent tissues and the blood filling it. The volume of tissue over a short period of time spent on the study is constant, and the volume of blood filling the organ is constantly changing, dynamically repeating the phases of the cardiac cycle. These changes in blood volume can be recorded using devices called plethysmographs (see figure 2). The photoplethysmography method is based on registration of the optical density of the studied tissue (organ). The examined tissue site is illuminated by infrared light, which after scattering (or reflection, depending on the position of the optocoupler) gets on the photoconverter. The intensity of light reflected or scattered by the studied area of tissue (organ) is determined by the amount of blood contained in it. Based on the data received from the photoconverter, a photoplethysmogram (see figure 3) and a photoplethysmatic figure (see figure 4) are built. Then determine the area of the photoplethysmographic figure in mm ² (S) (see figure 5). Further, according to the known values of heart rate and S, the values of linear functions (F ₁ and F ₂ ) are determined by the formulas:

$$\begin{array}{cc}\begin{array}{l}{F}_{\mathrm{one}}=0.33\ast H\mathrm{FROM}\mathrm{FROM}-\mathrm{0,052}\ast S-18.88\\ {\mathrm{<figure-callout\; id="2"\; label="F"\; filenames="00000019.png,00000023.png"\; state="\{\{state\}\}">F</figure-callout>}}_2=0.33\ast H\mathrm{FROM}\mathrm{FROM}-\mathrm{0,052}\ast S-18.88\end{array}& (2)\end{array}$$

At the same time, to assign the victim to one of the groups, the heart rate and S values are substituted into the formulas. If F ₁ > F ₂ , then the level of systolic pressure of the wounded person is below 100 mm Hg, therefore, the victim has a traumatic shock, if F ₁ ≤F ₂ , then the victim is assigned to the group with systolic blood pressure of more than 100 mm Hg. Art., therefore, the victim has no signs of traumatic shock.

According to the authors of the present invention, the use in the formulas (2) of the heart rate and S values obtained with a large error can lead to an error in determining the traumatic shock. In addition, the authors of the present invention believe that the use of the photoplethysmography method in emergency situations to determine the signs of traumatic shock is unacceptable, since any contamination (or burn) of the studied area of the skin affects its reflection or scattering in the device for recording photoplethysmogram.

Thus, the large complexity and duration of registration of the photoplethysmogram, the low accuracy of the obtained indicators of the known method for diagnosing traumatic shock makes it impossible to use it in emergency situations.

To eliminate these shortcomings in the known method for the diagnosis of traumatic shock, which consists in the fact that the patient is determined for the presence of pulse and breathing, in their absence, emergency care is provided and if the breath is not restored, a fatal outcome is diagnosed, cardiocycles are extracted, the cardiac cycle is determined, heart rate is determined abbreviations (HR), the determination of the presence or absence of a traumatic shock, additionally register an electrocardiogram, about -determination of hemodynamic parameters of the left ventricle of the heart, blood pressure definition, the definition of a traumatic shock for Weil classification.

The determination of hemodynamic parameters of the left ventricle of the heart is carried out by determining the final systolic size, determining the diastolic size, determining the final systolic volume and determining the diastolic volume of the left ventricle of the heart.

In this case, the determination of blood pressure is carried out by determining the stroke volume of blood, determining the mass of the stroke volume of blood, determining the acceleration of blood flow and calculating blood pressure.

According to the authors of the invention, the introduced actions while maintaining the advantages of the known method for the diagnosis of traumatic shock (non-invasiveness, cufflessness and objectivity) eliminate its disadvantages.

The essence of the invention is to use the method of electrocardiography in emergency situations to determine the signs of traumatic shock.

Registration of an electrocardiogram (EX) allows you to eliminate the main disadvantage of the known method for the diagnosis of traumatic shock - low accuracy. Also eliminated the complexity of recording photoplethysmogram. Registration of EX is carried out using a miniature wireless cardiac analyzer [3].

EKS is a valuable diagnostic tool that allows you to evaluate the regularity of heart contractions, their frequency, as well as calculate the values of blood pressure (BP).

The figure 7 shows a block diagram of an algorithm that implements the proposed method for determining the presence of traumatic shock. Diagnosing a traumatic shock involves the following steps:

1 - registration of EX;

2 - allocation of a cardiocycle;

3 - determination of hemodynamic parameters of the heart;

4 - determination of blood pressure;

5 - determination of the presence of traumatic shock;

6 - determine the degree of traumatic shock according to the Weil classification.

The figure 8 shows an example of an ECS with a dedicated R-R interval.

The figure 9 shows the classification of the severity of traumatic shock according to Weil [4].

The determination of heart rate in the proposed method for the diagnosis of traumatic shock is carried out on the basis of measuring the R-R interval of the ECS according to the formula:

$$H\mathrm{FROM}{\mathrm{FROM}}_{PRedl\mathrm{but}g}=\lfloor t_{RR}\cdot 60\rfloor +{0.5}_{\left(\mathrm{at}d/m\mathrm{and}n\right)}(3)$$

используется для обозначения ближайшего целого, не превосходящего t_RR·60.Where $$\lfloor t_{RR}\cdot 60\rfloor$$

used to indicate the nearest integer not exceeding t _RR · 60.

Since the duration t _{RR of the} interval RR EX is determined with an error of ± 0.001 second, then the determination of the heart rate by expression (3) will be more accurate than by expression (1).

Next, we consider the introduced actions in more detail.

The determination of the main hemodynamic parameters occurs according to the following formulas [5, 6]:

The final diastolic size (CDR) is determined by the formula:

$$\mathrm{TO}DR=\left(44.5-\mathrm{one\; hundred}\cdot t_{RS}\right)\cdot \left(t_{QR}+t_{RS}\right)-\mathrm{eleven}\cdot t_{RS},(\mathrm{four})$$

where t _QR is the time from the beginning of the Q wave to the top of the R wave in the absence of blockade of the left bundle branch block, and in the presence of the left bundle branch block, to the first vertex of the bifurcated R wave (R1), that is, t _QR = t _QR , c; t _RS is the time from the top of the R wave to the end of the S wave - in the absence of blockade of the legs of the bundle of His, and when the left leg of the bundle is blocked, instead of t _RS is the difference in time intervals from the first vertex of the bifurcated R wave to the end of the S wave (R1S) and from the first the vertices of the bifurcated tooth R to its second vertex (R ₁ R ₂ ), that is, t _RS = t _RS2 -t _S1 S ₂ , c;

The final systolic size (DAC) is determined by the formula:

$$\mathrm{TO}\mathrm{FROM}R=\left(44.5-\mathrm{one\; hundred}\cdot t_{RS}\right)\cdot \left(t_{QR}+t_{RS}\right)\cdot \sqrt{\frac{\mathrm{one}}{\sqrt[3]{\frac{t_{ST-T}}{t_{QRS}}}}}-\mathrm{eleven}\cdot t_{RS}\cdot \sqrt[3]{\frac{t_{ST-T}}{t_{\mathrm{<figure-callout\; id="3"\; label="Q\; R\; S"\; filenames="00000019.png,00000026.png"\; state="\{\{state\}\}">Q\; </figure-callout>}RS}}}\text{,}\left(\text{5}\right)$$

и при блокаде правой ножки пучка Гиса вместо t_ST-T сумма $$t_{ST-T}+t_{S_1{S}_2}$$

,с; $$КСР=22\cdot \left[t_{QRS}\sqrt{\frac{1}{\sqrt[3]{\frac{t_{ST-T}}{t_{QRS}}}}}-\mathrm{0,5}\cdot t_{RS}\cdot \sqrt[3]{\frac{t_{ST-T}}{t_{QRS}}}\right]$$

, и далее вычисляют при всех указанных видах сердечного ритма.where t _QRS is the time of the QRS complex, s; t _ST-T is the time from the end of the S wave to the end of the T wave - in the absence of blockade of the legs of the bundle of His, and with blockade of the left leg of the bundle of His instead of t _ST-T is the sum $$t_{ST-T}+t_{R_{\mathrm{one}}{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="00000019.png,00000023.png"\; state="\{\{state\}\}">R</figure-callout>}}_2}$$

and when the right bundle branch block is blocked, instead of t _{ST-T, the} sum $$t_{ST-T}+t_{S_{\mathrm{one}}{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="00000019.png,00000023.png"\; state="\{\{state\}\}">S</figure-callout>}}_2}$$

,from; $$\mathrm{TO}\mathrm{FROM}R=22\cdot \left[t_{QRS}\sqrt{\frac{\mathrm{one}}{\sqrt[3]{\frac{t_{ST-T}}{t_{QRS}}}}}-0.5\cdot t_{RS}\cdot \sqrt[3]{\frac{t_{ST-T}}{t_{QRS}}}\right]$$

, and then calculate for all these types of heart rate.

$$\begin{array}{cc}\begin{array}{l}\mathrm{TO}D\mathrm{ABOUT}=\frac{\mathrm{four}}{3}\ast \pi \ast \mathrm{TO}\mathrm{<figure-callout\; id="3"\; label="D\; R"\; filenames="00000019.png,00000026.png"\; state="\{\{state\}\}">D\; </figure-callout>}{R}^{}{}^3,\\ \mathrm{TO}\mathrm{FROM}\mathrm{ABOUT}=\frac{\mathrm{four}}{3}\ast \pi \ast \mathrm{TO}\mathrm{FROM}{R}^3\end{array}& (6)\end{array}$$

Determination of blood pressure (BP) is as follows.

First, determine the stroke volume of blood:

$$V_{mgn.\mathrm{at}sbR\mathrm{about}\mathrm{from}\mathrm{but}}=\mathrm{TO}D\mathrm{ABOUT}-\mathrm{TO}\mathrm{FROM}\mathrm{ABOUT},\left(\text{7}\right)$$

where KDO, KSO - the final diastolic and systolic volume, respectively.

Pressure calculation is performed according to the simplest formula:

$$P_{AD}=\frac{ma}{S},(8)$$

where m is the mass of the shock volume of blood, is defined as m = V _mnn . _emission * ρ of _blood ;

,a - acceleration, determined by the formula

,

where υ is the blood flow velocity, t _QRS is the duration of the QRS complex;

S is the cross-sectional area of the aorta.

According to the obtained blood pressure and heart rate, the presence of traumatic shock is diagnosed by the following criterion: blood pressure <100 and heart rate> 100. If the results obtained satisfy this condition, then the severity of the traumatic shock according to Weil’s classification is determined:

I degree (mild) - when blood pressure = 100, and heart rate> 100

II degree (average) - when blood pressure <100, and heart rate> 110-120

III degree (severe) - when blood pressure <60, and heart rate> 120.

Thus, the advantages of this method for the diagnosis of traumatic shock are the speed and accuracy of the study in emergency situations, as well as the possibility of using the electrocardiography method to assess the functional state of the victim’s body.

List of sources used

1. Patent 2325105 of the Russian Federation. A method for the diagnosis of traumatic shock / V.V. Boyarintsev, V.V. Suvorov, S.V. Gavrilkin, V.Yu. Markevich, M.V. Tyurin, A.V. Milyaev, Yu.A. Przegorlinsky. - / Declared 07/10/2006; Publ. 01/20/2008.

2. MetriaTM Wearable Sensor Technology Miniature Wireless Cardiac Analyzer // URL: www.averydennision.com. appeal date 03/15/2013.

3. Weil MG, Shubin G. "Diagnosis and treatment of shock." - M .: Medicine, 1971.

4. Patent 2107457 of the Russian Federation. A method for determining the main functional indicators of myohemodynamics of the left ventricle of the heart / Safonov M.Yu. RF patent No. 2107457, IPC A61B 5/02, 1998.

5. Schiller N.B. Two-dimensional echocardiographic determination of left ventricular volume, systolic function and mass. Summary and discussion of the 1989 recommendations of the American society of Echocardiography. Circulation 84.

6. RF patent 2264786. A method for determining the main indicators of myohemodynamics of the heart / O.N. Bodin, I.P. Burukina, A.A. Mitin, V.V. Ogonkov, A.N. Mitroshin, L.A. Bondarenko, L.E. Rudakova. - / Declared 04/19/2004, Publ. November 27, 2005, Bull. No. 33.

Claims (1)

A method for the diagnosis of traumatic shock, which consists in the fact that the victim determines the heart rate (heart rate), blood pressure (BP), and for blood pressure <100 and heart rate> 100, the presence of traumatic shock is diagnosed, characterized in that the electrocardiogram is recorded based on which calculate heart rate and hemodynamic parameters of the left ventricle, and the value of heart rate is determined by the formula:

after which, based on hemodynamic parameters, blood pressure is calculated by the formula:

, where m is the mass of the stroke volume of blood, calculated as: m = V * ρ of _blood ; a is the acceleration defined as

where υ is the blood flow velocity, t _QRS is the duration of the QRS complex; S is the cross-sectional area of the aorta, V is the stroke volume of blood.

Images