RU2185093C1 - Device examining regional blood-filling and lungs ventilation - Google Patents

Abstract

FIELD: medicine, examination of disturbances in blood-filling and lungs ventilation. SUBSTANCE: device has controlled high-frequency generator, radiator, matrix of pickups which is installed opposite rear surface of thorax, detector, analog-to-digital converter, unit recording measured data, two multiplexers and two feedback channels. Each feedback channel incorporates recorder, digital-to-analog converter and amplifier. Outputs of amplifiers are connected to inputs controlling frequency and amplitude of signal of generator. Recorder of measured data is built on elements which present data in the form of breathing curves changing in time and evaluation of blood-filling and ventilation per each of six regions of lungs is carried out. Device displays expanded functions making it possible to determine both regional blood-filling and regional ventilation of lungs and demonstrates high degree of authenticity of obtained data. EFFECT: increased informativity and accuracy of obtained data. 6 cl, 9 dwg

Description

 The invention relates to medicine, in particular to devices for the study of disorders of blood supply and ventilation, and can be used for screening and monitoring of these disorders for diagnostic purposes, as well as in health insurance and medical control.

BACKGROUND OF THE INVENTION
A device is known that is used to determine the functions of external respiration of the lungs and respiratory system, consisting of an emitter of electromagnetic waves, a matrix of sensors that measure the patient’s breathing parameters by a non-contact method, and a unit for recording the measured parameters made in the form of a personal computer and processing data [1].

 However, the known device does not allow the determination of regional ventilation of the lungs and does not allow to measure their blood supply.

 The closest analogue is a device for remote study of respiratory functions, containing a high-frequency generator with a radiating plate, a matrix of respiratory sensors, a communication channel in which the signals from the sensors are demodulated and filtered using the detector unit and fed to the input of the multiplexer, and from its output to channel amplifier input. Analog signals from the output of the communication channel are fed to the input of an analog-to-digital converter (ADC), from the output of which they are fed to a recording unit, which can be used as an IBM-PC [2].

 This device allows you to register the values of MOD, VC, FVC, MVL, etc. and after comparing the data with the proper values to determine the degree of insufficiency of ventilation.

 The known device, however, does not allow to determine lung ventilation by region and measure their blood supply.

 The present invention is directed to a device with advanced functions, which determines both regional blood supply and regional lung ventilation.

 The technical result of the invention also consists in increasing the reliability of the data obtained, their information content and accuracy.

SUMMARY OF THE INVENTION
The claimed technical result is achieved due to the fact that the device for determining the functional parameters of respiration, containing a high-frequency generator, emitter, sensor matrix, the outputs of which are connected to the information inputs of the first multiplexer, a detector, an analog-to-digital converter, the output of which is connected to the first input of the unit registration of the measured data, the control unit, the first and second outputs of which are connected to the control inputs of the first multiplexer and analog-to-digital converter, are introduced two feedback channels, each of which consists of a series-connected register, a digital-to-analog converter and an amplifier, while the high-frequency generator is controlled, the inputs of the feedback channel registers are connected respectively to the first and second outputs of the measured data recording unit, and the outputs of the channel amplifiers feedback - to the inputs of controlling the frequency and amplitude of the signal of the high-frequency generator, the output of which is connected to the emitter through a second multiplexer, the control input of the cat It is connected to the third output of the control unit, the fourth, fifth, sixth and seventh outputs of which are connected to the control inputs of the corresponding digital-to-analog converters and feedback channel registers, and the eighth output is connected to the second input of the measured data recording unit, and the detector input is connected to the output the first multiplexer, and the output is to the input of an analog-to-digital converter.

 In addition, the emitter is made in the form of a matrix of emitters.

 In addition, the unit for recording the measured data is made on operational and read-only memory devices, a unit for comparing parameters, the inputs and outputs of each of which are connected via the data bus with the inputs and outputs of the processor and the input-output interface, the first and second inputs of which are respectively the first and second the inputs of the measured data recording unit, the first and second outputs of which are the first and second outputs of the I / O interface, the third input and output of which are connected respectively to the keyboard and to the device display, and additional inputs and outputs are a bus connection with an external computer.

 The measured data recording unit may be performed on a personal computer.

 In addition, the instrument is equipped with a calibration tool.

 The calibration tool is made in the form of a simulator of the region of the lung, the area of which corresponds to the area of the sensor matrix, and is a sealed bag made with the possibility of injection of a blood substitute into it with a syringe.

The implementation of the device for determining regional blood supply and ventilation of the lungs is illustrated by the following drawings and drawings:
figure 1 presents a block diagram of a device
in FIG. 2 shows the relative position of the main blocks of the device during operation,
figure 3: physical model for measuring blood supply and ventilation of the lungs - 3A, the breathing curve in time - 3B, the choice of the optimal received signal - 3B,
figure 4 (a, b) shows the use in the device of a means of calibration,
figure 5 is a block diagram of a research program algorithm,
figure 6 is a block diagram of the algorithm of the unit for recording the measured data.

 The device comprises (Fig. 1) a high-frequency generator 1, an emitter 2, a sensor matrix 3, a first multiplexer 4, a detector 5, an analog-to-digital converter 6, a measured data recording unit 7, a control unit 8, the first 9 and second 10 feedback channels made respectively on registers 11 and 14, digital-to-analog converters 12 and 15 and amplifiers 13 and 16, the second multiplexer 17.

 Block 7 recording the measured data consists of random access memory - RAM 18, read-only memory - ROM 19, unit 20 for comparing parameters, processor 21, input / output interface 22, information display device 23, data input unit - keyboard 24 and data bus 25 .

 Due to the presence of feedback channels 9 and 10, the high-frequency generator 1 is tuned in frequency and amplitude of the output signal to optimally emitted by the emitter and, accordingly, optimally received by the sensors signals of the electromagnetic field. This happens as follows.

The voltage obtained at a single Udi sensor depends on the change in the volume of the lung locus covered by this sensor (Fig.4b), and is defined as
Udi = VLtlc - VLrv,
where VLtlc is the locus volume at the total lung capacity;
VLrv is the locus volume with residual lung capacity.

But on the other hand, this voltage corresponds to a change in the electromagnetic field ΔE upon interaction with the blood of the lung locus [5] and is defined as
ΔE = [n-1] (2π / λx) E _o ΔXcos (ωt-2π / λx-π / 2),
where n is the refractive index of a substance in an electromagnetic field;
E ₀ - field strength of the emitter;
ΔX - change in the distance from the surface of the chest to the emitter due to changes in the volume of the locus of the lung from VLrv to VLtlc.

Therefore, Udi is an extreme frequency-dependent function (Fig.3c) and is a function of frequency versus time
Udi = Ф (df / dt) with VLtIc - const.

The measurement process is as follows (figure 1). The generator 1 through the multiplexer 17 is connected to the emitters 2, which are sources of the field E ₀ (whose intensity is 5-20 V / m). The created field is recorded by a matrix of sensors 3. The field strength depends on the medium through which it penetrates. In this case, the environment is the lungs. When the patient breathes, the environmental parameters change, because the amount of blood and air in the lungs changes, and the field strength accordingly changes to E _s = E ₀ + ΔE (ΔE = ΔEo + ΔEx, where ΔE ₀ is the change in field strength due to the presence of lungs, ΔE _x is the change in field strength due to volume changes blood and air in the lungs when breathing) - figa. The recorded signals from the sensors are multiplexed and fed to the detector 5 and then in the form of a low-frequency signal to the analog-to-digital converter 6. The digitized data is transmitted to the recording device, where it is compared with the parameters previously entered into the ROM 19. Based on the comparison results, data are generated to control the generator 1, so that Udi becomes maximum (calibration). A field of sensors 3 is again polled for this field, and these data are entered into RAM 18. After processing, the results are output to a display device 23 in the form of respiration curves and blood supply parameters of lung regions in arbitrary units. If you want to memorize a large number of studies, it is possible to connect to an external computer, which can also work in the mode of a registrar and an information store.

SURVEY METHODOLOGY
The doctor-operator turns on the device and performs calibration. It is carried out in two modes:
1 - using a calibration device and a simulator of the region of the lungs (Fig. 4A);
2 - on a certain type of healthy patient.

 In the mode, calibration begins by installing at a certain distance X the panel of the sensor matrix from the panel of the matrix of emitters with a simulator of the lung region (figa).

 Then, the piston of the blood-containing vessel is uniformly fed. In this case, the blood substitute moves to the simulator of the lung region, and the volumes of the lung loci change to the maximum VLtIc.

After that, these volumes are fixed and in the time interval from t ₀ to t ₁ , the control unit 8 through the second multiplexer 17 connects the output of the generator 1 to the emitter 1. Next, the control unit 8 through the first multiplexer 4 connects the sensor matrix 3 to the detector 5, followed by digital conversion. The received data is transmitted to the unit 7 for recording the measured data, where they are processed and stored. Then, the processed data goes to channels 9 and 10, where, using the control unit 8, this data is received in registers 11 and 14, followed by digital-to-analog conversion and the supply of amplified signals to the inputs of generator 1. This process is repeated until, by changing the frequency and amplitude of the signal of the generator 1 will not achieve the maximum value Ud, which is stored in the ROM 19. Then the pistons move in the reverse order for a time from t ₁ to t ₂ . In this case, the blood substitute is removed from the simulator of the lung region, and the volumes of the lung loci change to the minimum VLrv. After that, these volumes are fixed and the measuring and conversion process is carried out through the above blocks. Block 7 registration of the measured data calculates the vital capacity of the lung region (MKvc) according to the formula
VRvc = ∑Udi = ∑ (VLtIc-VLrv).

 In mode 2, the calibration procedure remains the same as in mode 1, only instead of a simulator of the lung region, all measurements are performed on a strictly defined region of the lung of a healthy patient with previously known spirometric parameters.

 After calibrating the device, the doctor starts the study program.

 In the dialogue mode, the doctor enters the patient’s passport and anthropometric data into RAM 18 of the device: age, gender, height, weight, race, etc. (by which all the proper respiration parameters are determined, in particular the lung capacity [3], as well as the type of chest , expressed as the physiological coefficient of the patient Kf. In this case, the normosthenic type of the chest is Kf = 1.0, the asthenic type Kf = 0.8, and the hypersthenic type Kf = 3 1.2. These individual features are associated with the geometric parameters of the groove. the bottom of the cell in the projection of the back-chest in two directions: front-side size and upper-lower size.Accounting for the coefficient Kf - allows you to automatically disable a certain number of sensors that are not involved in the measurements.

 The patient is seated in a chair, in the hinged back of which is mounted a panel with a matrix of sensors 3 (figure 2). The doctor sets at a certain distance in front of the surface of the patient’s chest in a selected region of the lungs a matrix of emitters 2, which is the source of the field. Sensors 3 and emitters 2 are located in the YZ plane. The emitters 2 are moved in the direction of the X axis. Their distance from the chest of the subject is 5-30 cm. During the examination, the patient is in a chair in a free, relaxed position in a sitting or lying position.

The location of the sensor array opposite the rear surface of the chest compared to its installation in the prototype method from the front surface of the chest has several advantages. A closer location of the lungs, a smaller thickness of the chest wall, a significantly smaller difference between the chest of a man and a woman can reduce the distance between the patient’s chest and sensors, thereby increasing the accuracy of the measured parameters, and in the prone position more fully examine the blood supply to the lungs, because . in this case, more blood accumulates from the back,
The doctor starts the measurement process. Patient breathing curves appear on the display device.

The doctor gives commands for the patient to perform breathing tests and monitors their performance according to the breathing curve. Respiratory curves are recorded in different modes (VC-VC, FVC-FVC, MBL-MVV, etc.). The number of samples is determined by the doctor. Upon completion of all necessary tests, the doctor completes the measurement process
Then, using the keyboard 24, the doctor selects zones with correctly performed samples on the breathing curves, selects and analyzes certain characteristic zones, and outputs to the display device the necessary estimated blood supply parameters for the region of each lung, obtained by summing the signals from the sensor matrix 3.

 The method of such examination of patients is described in a method for studying regional blood supply and ventilation of the lungs, protected by RF patent 2160044 dated December 10, 2000.

The algorithm of the research program is shown in figure 5. According to this algorithm, during the measurement
1. The matrix of sensors is interrogated, the aij values proportional to the field strength during interaction with the substance (lungs) are taken from them.

2. The normalized indication of the measured parameter is calculated by the formula bij = Δ (a _ij / a _max ), where Δ is the differential value of the normalized digital readings of the measured parameters of one sensor for samples with and without the patient, a _ij is the current value of the signal from the sensor, and _max - the maximum value of aij for the previous measurement time. These nominal values are displayed in numerical form on the display device. The sum of bij values is calculated by region and by lung. The obtained values are displayed on the graphs in the form of breathing curves, as well as in numerical form. In addition, based on these values, cartometric images of each lung region are constructed.

 3. At the end of the measurement process and the possibility of connecting via an interface 22 to an external calculator, the doctor can additionally obtain the FLOW-VOLUME curves for each region of the lungs. In this case, all the research results after the treatment performed by the doctor are stored in a computer database. And through an information network, data may be available to other doctors. Information in the database can be edited and supplemented at the request of the doctor.

The device can be performed as follows:
G - controlled generator 1 is made on a chip (MS) K531GG1. MI - a matrix of emitters 2, made in the form of L-shaped resonant LC circuits [4]. MD - sensor array 3, made in the form of L-shaped resonant LC circuits [4]. MX1 - analog signal multiplexer 4 is made on MS KR561KP2. MX2 - analog signal multiplexer 17 is made on MS KR561KP2. ADC - analog-to-digital Converter 6 is part of the MS R1S16S71. BU - control unit 8 is part of the MC PIC16C71. UOS1 - feedback amplifier 13 is made on the MS KR140UD8. UOS2 - feedback amplifier 16 is made on MS KR140UD8. PrOCl - feedback register 11 is made on MS KR1564IR23. RgOS2 - feedback register 14 is made on MS KR1564IR23. DAC1 12 is made on MS K572PA1. DAC2 15 is made on MS K572PA1. D - detector 5 is made on the basis of series-connected MS K175UVZ, K175DA1 and KR140UD8.

 The measured data recording unit 7 is based on the PIC16C73A MS, it includes: RAM, ROM, processor, data bus, parameter comparison unit. UO - display device 23 is made on the basis of LCD and BVDP - data input unit (keyboard) 24, is made on the basis of microswitches MP-1. Additionally, the registrar is connected via an input-output interface 22 with another external computer, which can be used as a registrar and an external database.

 The algorithm of the measurement data recording unit is shown in Fig.6.

 Using this device, 100 patients with various lung pathologies were examined. High accuracy of the measured parameters was established both for blood supply and ventilation of the studied lung regions.

 The device can be made both in the form of an autonomous portable device, or in the form of a stationary one, interfaced with an external computer.

Sources of information
1. RU 96106724 C1 (SOKOLOVA BC et al.), 07.27.1998.

 2. RU 2122344 C1 (Zhuravlev V.F.), 11/27/1998

 3. CLEMENT R.F. and other instructions for the use of formulas and tables of due values of the main spirometric indicators. L., 1986, 79 pp.

 4. Pisarevsky A. M. Construction of block diagrams and oscillatory systems of transmitters of long, medium and short waves. M., ed. LEIZ, 1960, 54 p.

Claims (6)

 1. A device for determining the functional parameters of respiration, comprising a high-frequency generator, an emitter, an array of sensors, the outputs of which are connected to the information inputs of the first multiplexer, a detector, an analog-to-digital converter, the output of which is connected to the first input of the measured data recording unit, a control unit, the first and the second outputs of which are connected to the control inputs of the first multiplexer and analog-to-digital converter, characterized in that two feedback channels are introduced into it, each and of which consists of a series-connected register, digital-analog converter and amplifier, while the high-frequency generator is controlled, the inputs of the feedback channel registers are connected respectively to the first and second outputs of the measured data recording unit, and the outputs of the feedback channel amplifiers are connected to the frequency control inputs and the amplitude of the signal of the high-frequency generator, the output of which is connected to the emitter through a second multiplexer, the control input of which is connected to the third output of the unit control, the fourth, fifth, sixth and seventh outputs of which are connected to the control inputs of the corresponding digital-analog converters and registers of feedback channels, and the eighth output is connected to the second input of the measured data recording unit, the input of the detector connected to the output of the first multiplexer, and the output to analog-to-digital converter input.  2. The device according to p. 1, characterized in that the emitter is made in the form of a matrix of emitters.  3. The device according to any one of paragraphs. 1 and 2, characterized in that the unit for recording the measured data is made on operational and read-only memory devices, a unit for comparing parameters, the inputs and outputs of each of which are connected via the data bus with the inputs and outputs of the processor and the input-output interface, the first and second inputs of which are respectively the first and second inputs of the measured data recording unit, the first and second outputs of which are the first and second outputs of the I / O interface, the third input and output of which are connected respectively to the keyboards ur and to the display device, and additional inputs and outputs are the communication bus with an external computer.  4. The device according to any one of paragraphs. 1 and 2, characterized in that the unit for recording the measured data is made on a personal computer.  5. The device according to any one of paragraphs. 1 and 2, characterized in that the device is equipped with a means of calibration.  6. The device according to p. 5, characterized in that the calibration tool is made in the form of a simulator of the region of the lung, the area of which corresponds to the area of the sensor matrix and is a sealed bag made with the possibility of injection of a blood substitute into it with a syringe.

Images