JP4563766B2 - Blood pressure measurement device, blood pressure measurement method, control program, and computer-readable storage medium - Google Patents

Description

  The present invention relates to a blood pressure measurement device, and more particularly to a blood pressure measurement device including a plurality of different pulse wave detection sensors and a sensor for detecting body movement.

Conventional blood pressure measuring devices using pulse waves are roughly divided into a measurement method, a photoelectric pulse wave method, a pressure pulse wave method, and a Korotkoff method. The photoelectric pulse wave method is a light emitting element for detecting a pulse wave in a cuff. It is equipped with a light receiving element. Light is emitted from the light emitting element to the blood vessel, the light reflected by the blood flow is received by the light receiving element, and the blood pressure is measured. The pressure pulse wave method is an air system that continues to the cuff. The deployed pressure sensor detects the fluctuation of the air pressure in the cuff that vibrates due to the vibration of the blood vessel wall, and measures the blood pressure. In the Korotkoff method, a Korotkoff sound is detected and a blood pressure is measured by a microphone arranged in the cuff periphery. Because of the above-mentioned principle, measurement noise occurs due to direct or indirect factors due to body movement in any measurement. A method has been proposed in which a person judges and selects a probable result.
Japanese Patent No. 3340324

  Conventionally, in the case where measurement is performed by combining or switching different types of measurement methods, the judgment of the validity of the blood pressure measurement result obtained by each measurement method must be performed by humans unless it is an obvious abnormal value, There was a problem that an objective judgment could not be made.

  The present invention has been made in view of the problems as described above, and in the case where measurement is performed by using or switching between a plurality of different measurement methods, the blood pressure enables selection of an objective and appropriate blood pressure measurement result. A measuring device and a blood pressure measuring method are provided.

  In order to solve this problem, a blood pressure measurement device according to the present invention includes a first pulse wave signal detection unit that detects a pulse wave signal according to a first principle, and a second pulse wave signal that detects a pulse wave signal according to a second principle. Pulse wave signal detection means, a cuff that is attached to the blood pressure measurement site, and the first pulse wave signal detection means and the second pulse wave signal detection means are arranged at appropriate positions, and body motion detection means that detects body movement And the blood pressure value derived from the pulse wave detected by the first pulse wave signal detection means based on the feature of the body movement obtained by the body movement detection means, or the second pulse wave signal detection means Blood pressure value selecting means for selecting one of the blood pressure values derived from the pulse wave detected by.

  The blood pressure measurement method according to the present invention includes a first pulse wave signal detection step of detecting a pulse wave signal according to a first principle at an appropriate position of a first cuff attached to a blood pressure measurement site, In an appropriate position of the cuff, a second pulse wave signal detection step for detecting a pulse wave signal according to the second principle, a body motion detection step for detecting body motion, and characteristics of the body motion obtained by the body motion detection step Based on the blood pressure value derived from the pulse wave detected by the first pulse wave signal detection step or the blood pressure value derived from the pulse wave detected by the second pulse wave signal detection step A blood pressure value selection step of selecting one of them.

  A control program for executing the blood pressure measurement method according to the present invention is also provided. The blood pressure measurement control program according to the present invention has a first principle at an appropriate position of the first cuff attached to the blood pressure measurement site. A program code for executing a first pulse wave signal detection step for detecting a pulse wave signal by means of a second pulse wave signal for detecting a pulse wave signal according to a second principle at an appropriate position of the first cuff. Based on the program code for executing the detection step, the program code for executing the body motion detection step for detecting the body motion, and the characteristics of the body motion obtained by the body motion detection step, the first Blood pressure for selecting either the blood pressure value derived from the pulse wave detected by the pulse wave signal detection step or the blood pressure value derived from the pulse wave detected by the second pulse wave signal detection step And a program code for performing the selection process.

  According to the present invention, the body motion level obtained by the body motion level detection means during the blood pressure measurement period of the blood pressure measurement site can be used as a determination material, and the blood pressure value obtained by the first blood pressure determination means It is possible to provide a blood pressure measurement device capable of objectively selecting an appropriate blood pressure value from the two blood pressure values obtained by the second blood pressure determining means.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the constituent elements described in this embodiment are merely examples, and are not intended to limit the scope of the present invention only to them.

(First embodiment)
<Device configuration>
FIG. 1 is a block diagram illustrating a configuration of a blood pressure monitor according to the embodiment. In the figure, reference numeral 1 denotes a cuff, which is fixed to a blood pressure measurement site so that a blood vessel can be compressed. Reference numeral 2 denotes a rubber tube that forms a flow path of air into the cuff 1. Reference numeral 3 denotes a pressure pump that feeds pressurized air into the cuff 1. 4 is a rapid discharge valve, which rapidly reduces the pressure in the cuff 1. Reference numeral 5 denotes a fine exhaust valve, which reduces the pressure in the cuff 1 at a constant speed (for example, 2 to 3 mmHg / sec). Reference numeral 6 denotes a pressure sensor, which changes an electrical parameter according to the pressure in the cuff 1. A pressure pulse wave detection amplifier (AMP) 7 detects an electrical parameter of the pressure sensor 6, converts it into an electrical signal, amplifies it, and outputs an analog cuff pressure signal P.

  Reference numeral 8 denotes a pulse wave sensor installed in the cuff 1, which includes an LED 8a that irradiates light to a pulsating vascular blood flow, and a phototransistor 8b that detects reflected light from the vascular blood flow (FIG. 2). A photoelectric pulse wave detection amplifier (AMP) 9 amplifies the output signal of the phototransistor 8b and outputs an analog pulse wave signal M. Here, the LED 8a is connected with a light amount control unit 18 for automatically changing the light amount, while the pulse wave detection amplifier 9 is controlled with a gain control unit 19a for changing the gain and a time constant control for changing the time constant of the amplifier 9. The part 19b is connected. Further, in order to detect body movement, the apparatus has an acceleration sensor 20 and a body movement detection amplifier (AMP) 21 and outputs an acceleration signal A. Reference numeral 10 denotes an A / D converter (A / D), which converts analog signals M, P, and A (not shown) into digital data D (not shown). The acceleration sensor 20 is preferably installed in the vicinity of the cuff 1.

  A control unit (CPU) 11 performs main control of the blood pressure measurement device. The CPU 11 has an adjustment pressure register 11a that stores the adjustment pressure. Details of this control will be described later according to the flowchart of FIG. Reference numeral 12 denotes a ROM which stores, for example, the control program shown in FIG. A RAM 13 includes a data memory, an image memory, and the like. A liquid crystal display (LCD) 14 displays the contents of the image memory. Reference numeral 16 denotes a keyboard which can be used to set a measurement start command, an adjustment pressure value, and the like by a user operation. A buzzer 15 informs the user that the device has sensed that the key in the keyboard 16 has been pressed, the measurement has been completed, and the like. In this example, the adjustment pressure register 11 a is provided in the CPU 11, but an adjustment pressure storage unit may be provided in the RAM 13.

  FIG. 3 is an external perspective view of the blood pressure monitor according to the embodiment. In the figure, reference numeral 17 denotes a sphygmomanometer body, which includes a configuration excluding the cuff 1 and the pulse wave sensor 8 of FIG. Here, the rubber tube 2 includes a signal line (not shown) with the pulse wave sensor 8 and is connected to the cuff 1 and the pulse wave sensor 8 (not shown). The display panel 14 of the LCD uses a dot matrix type display panel, and therefore can display various information (for example, characters, figures, signal waveforms, etc.). Reference numeral 20 denotes a power switch, and the keyboard 16 has a measurement start switch (ST) and a numeric keypad for inputting a cuff pressure value and the like.

<Operation of the device>
Next, the operation of the sphygmomanometer according to the present embodiment will be described below. FIG. 4 is a flowchart of a measurement processing procedure in the sphygmomanometer according to the first embodiment.

  When the apparatus is turned on, self-initial diagnosis processing (not shown) is first performed to initialize the apparatus. Thereafter, the process is started by pressing the measurement start switch ST.

  In step S101, the cuff pressure P is read, and in step S102, it is determined whether or not the residual pressure of the cuff 1 is within a specified value. If the residual pressure exceeds the specified value, “residual pressure error” is displayed on the LCD 14 in step S123. If the residual pressure is within the specified value, a cuff pressure value (for example, a value larger than the maximum blood pressure value of 120 to 210 mmHg) is set using the keyboard 16 in step S103, and the light amount and gain are set to predetermined values in step S104. Set to.

  When the setting of the pressurization value and the light quantity / gain is completed, the quick exhaust valve 4 and the fine exhaust valve 5 are closed in steps S105 and S106. In step S107, driving of the pressure pump 3 is started and pressurization (pressure increase) is started.

  In step S108, it is determined whether or not the cuff pressure is higher than the pressure value U set in S103. If P> U, pressurization is continued. When P> U, the pressure pump 3 is stopped in step S109.

  In step S110, the fine exhaust valve 5 is opened. This is the start of the measurement process at the time of pressure reduction (pressure reduction), and the cuff pressure starts decreasing at a constant speed (for example, 2 to 3 mmHg / sec). At the same time, detection of acceleration by the body motion detection means (acceleration sensor) is started, and detection of the pulse wave is started by the first blood pressure determination means (photoelectric pulse wave method) and the second blood pressure determination means (pressure pulse wave method). Is done. In the first blood pressure determining means, light is emitted to the blood vessel by the light emitting element 8a, and the reflected light reflected by the blood flow is received by the light receiving element 8b, and this received light amount data (varies depending on the blood flow in the blood vessel). The amount of reflection) is detected as a photoelectric pulse wave. At the same time, in the second blood pressure determining means, the air pressure in the cuff, that is, the vibration amplitude that changes according to the amount of compression (vibration of the blood vessel wall corresponding to the pulsation vibrates through the cuff. The pressure sensor detects the air pressure in the cuff as a pressure pulse wave. During this time, data processing by each functional block is performed in step S111, and the systolic blood pressure and the diastolic blood pressure are measured by applying a predetermined algorithm to each of the photoelectric pulse wave signal and the pressure pulse wave signal. In step S112, it is determined whether or not a minimum blood pressure value is detected during decompression. If both of the blood pressure values measured from the photoelectric pulse wave data and the pressure pulse wave data have not been detected, measurement is continued. In step S113, it is determined whether or not the cuff pressure is lower than a predetermined value L (for example, 40 mmHg). If P <L, it is still in the normal measurement range, and the flow returns to step S111. On the other hand, when P <L, the cuff pressure is no longer lower than the normal measurement range, so that normal data cannot be acquired for both the photoelectric pulse wave signal and the pressure pulse wave signal (for example, the determined maximum blood pressure value is 40mmHg or less) displays “measurement error” on the LCD 14 in step S114. At that time, if necessary, detailed information such as “signal abnormality during decompression” is additionally displayed. In step S115, the quick exhaust valve 4 is opened.

  In step S116, depending on whether or not the value obtained by the acceleration sensor exceeds a predetermined value C set in advance, the highest blood pressure value determined from the photoelectric pulse wave and the lowest blood pressure value or the highest blood pressure determined from the pressure pulse wave. Select either the value or the minimum blood pressure value. At this time, if it exceeds the predetermined value C, it is determined that there is a large body movement during the measurement, and an accurate blood pressure cannot be obtained depending on the pressure pulse wave, and the highest blood pressure value determined from the photoelectric pulse wave and the lowest If the blood pressure value is selected and the predetermined value C or less, it is desirable to select the maximum blood pressure value and the minimum blood pressure value determined from the pressure pulse wave.

  In step S117, the selected maximum blood pressure value and minimum blood pressure value are displayed on the LCD 14, and in step S118, a buzzer is sounded to notify the user of the end of measurement.

  As described above, from the sphygmomanometer of the present embodiment, from the blood pressure measurement result of the photoelectric pulse wave method that is the first blood pressure determination means and the blood pressure measurement result of the pressure pulse wave method that is the second blood pressure determination means, It is possible to objectively select an appropriate blood pressure to be displayed as a result, based on the signal strength of the acceleration sensor, which is a body motion detection means, whether or not a threshold value corresponding to a predetermined acceleration is exceeded.

(Second Embodiment)
An example will be described below as a second embodiment of the blood pressure measurement device according to the present invention.

  The apparatus configuration and operation are substantially the same as those in the first embodiment, but as a body movement period detecting means, the apparatus further has a function of calculating a body movement period component using the CPU 11 using data of an acceleration sensor, and step When selecting either the systolic blood pressure value and the systolic blood pressure value determined from the photoelectric pulse wave or the systolic blood pressure value or the systolic blood pressure value determined from the pressure pulse wave in S116, it is used more effectively for the following reason. I can do it.

  In comparison of the photoelectric pulse wave method and the pressure pulse wave method in the blood pressure measurement method, the pressure pulse wave method is generally detected via the air based on the measurement principle, so the body motion with a short cycle (fast) Disturbance vibration due to is attenuated by air and is not easily affected. On the other hand, the photoelectric pulse wave system has a property that it is easily affected by body movement with a short period. Therefore, in the measurement in the case where the body motion level is smaller than a predetermined value and there is a short (fast) body motion, it is more desirable to determine the blood pressure by the pressure pulse wave method. FIG. 5 shows an example of a method for selecting a photoelectric pulse wave method and a pressure pulse wave method based on characteristics of body movement during the blood pressure measurement period. In this embodiment, the photoelectric pulse wave is used when the noise is small. However, depending on the measurement site, the pressure pulse wave may be detected more stably. In this case, the pressure pulse wave may be selected when the noise is small.

(Third embodiment)
A third embodiment of the blood pressure measurement device according to the present invention will be described below as an example.
As described above, in the first and second embodiments, the irradiation unit (LED 8a) that irradiates light to the blood flow of the blood vessel to the single cuff that compresses the blood pressure measurement site and the reflected light from the blood flow. A light receiving portion (phototransistor 8b) for detection is provided.
On the other hand, in the third embodiment, two cuffs that respectively press two different blood pressure measurement sites are provided, and both of them are irradiated with light (see FIG. 6: LEDs 8a and 23a) and light reception for detecting reflected light. Unit (see FIG. 6: phototransistors 8b and 23b), and can simultaneously measure blood pressure at a plurality of sites. A sensor using a different measurement principle (such as a method using a pressure pulse wave) may be used for blood pressure measurement.

  Since other configurations and operations are the same as those in the first and second embodiments, description thereof will be omitted.

  The blood pressure measurement device according to the present embodiment makes it possible to objectively select the most probable result from the blood pressure measurement results by a plurality of methods based on the characteristics of body movement in the blood pressure measurement period, and the blood pressure measurement site has high accuracy. Blood pressure can be measured.

(Other embodiments)
Although the embodiments of the present invention have been described in detail above, the present invention may be applied to a system constituted by a plurality of devices or may be applied to an apparatus constituted by one device.

  The present invention can also be achieved by supplying a program that realizes the functions of the above-described embodiments directly or remotely to a system or apparatus, and the system or apparatus reads and executes the supplied program code. The Accordingly, the program code itself installed in the computer in order to realize the functional processing of the present invention by the computer is also included in the technical scope of the present invention.

  In this case, the program may be in any form as long as it has a program function, such as an object code, a program executed by an interpreter, or script data supplied to the OS.

  As a recording medium for supplying the program, for example, floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW, magnetic tape, nonvolatile memory card ROM, DVD (DVD-ROM, DVD-R) and the like.

  As another program supply method, a client computer browser is used to connect to an Internet homepage, and the computer program itself of the present invention or a compressed file including an automatic installation function is downloaded from the homepage to a recording medium such as a hard disk. Can also be supplied. It can also be realized by dividing the program code constituting the program of the present invention into a plurality of files and downloading each file from a different homepage. That is, a WWW server that allows a plurality of users to download a program file for realizing the functional processing of the present invention on a computer is also included in the claims of the present invention.

  In addition, the program of the present invention is encrypted, stored in a storage medium such as a CD-ROM, distributed to users, and key information for decryption is downloaded from a homepage via the Internet to users who have cleared predetermined conditions. It is also possible to execute the encrypted program by using the key information and install the program on a computer.

  In addition to the functions of the above-described embodiments being realized by the computer executing the read program, the OS running on the computer based on the instruction of the program is a part of the actual processing. Alternatively, the functions of the above-described embodiment can be realized by performing all of the processes.

  Furthermore, after the program read from the recording medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion board or The CPU or the like provided in the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

It is a block diagram of the apparatus of 1st Embodiment. It is explanatory drawing which showed operation | movement of the sensor which detects a photoelectric pulse wave signal. It is an external view of the sphygmomanometer of the first embodiment. It is explanatory drawing which showed the flowchart of operation | movement of 1st Embodiment. It is explanatory drawing which showed selection of the measuring method based on the characteristic of the body movement of 2nd Embodiment. It is a block diagram of the apparatus of 3rd Embodiment.

Claims (13)

First pulse wave signal detection means for detecting a pulse wave signal according to the first principle;
Second pulse wave signal detection means for detecting a pulse wave signal according to the second principle;
A first cuff disposed at a blood pressure measurement site that detects a pulse wave using the first pulse wave signal detection means and the second pulse wave signal detection means;
Body movement detecting means for detecting body movement;
A blood pressure value derived from the pulse wave detected by the first pulse wave signal detection means based on the characteristics of the body movement obtained by the body movement detection means, or the second pulse wave signal detection means A blood pressure measurement device comprising: a blood pressure value selection unit that selects any one of the blood pressure values derived from the pulse wave detected by the method. The body movement detecting means includes
Level detection means for detecting the magnitude of body movement;
A period detecting means for detecting a period of body movement,
The blood pressure measurement according to claim 1, wherein the characteristic of the body movement is at least one of a magnitude of the body movement detected by the level detection unit and a period of the body movement detected by the cycle detection unit. apparatus. Furthermore, it has the 2nd cuff with which at least one blood pressure determination means was mounted | worn with the said 1st cuff, and can measure the blood pressure of a different location simultaneously. 2. The blood pressure measurement device according to 2. The blood pressure determining means includes
Third pulse wave signal detection means for detecting a pulse wave signal according to the first principle;
A fourth pulse wave signal detecting means for detecting a pulse wave signal according to the second principle;
The blood pressure value derived from the pulse wave detected by the third pulse wave signal detection means based on the feature of the body movement obtained by the body movement detection means, or the fourth pulse wave signal detection means Second blood pressure value selecting means for selecting any one of the blood pressure values derived from the pulse wave detected by
The blood pressure measurement device according to claim 3, comprising: A first pulse wave signal detection step of detecting a pulse wave signal at the compression site by the first cuff according to the first principle;
A second pulse wave signal detecting step of detecting a pulse wave signal at a compression site by the first cuff according to a second principle;
A body motion detection step for detecting body motion;
A blood pressure value derived from the pulse wave detected by the first pulse wave signal detection step or the second pulse wave signal detection step based on the characteristics of the body motion obtained by the body motion detection step. And a blood pressure value selecting step of selecting any one of blood pressure values derived from the pulse wave detected by the blood pressure measurement method. The body motion detection step includes
A level detection process for detecting the magnitude of body movement;
Including a cycle detection step of detecting a cycle of body movement,
The blood pressure measurement according to claim 5, wherein the characteristic of the body movement is at least one of the magnitude of the body movement detected by the level detection step and the period of the body movement detected by the cycle detection step. Method. Furthermore, it has a blood pressure determination step for determining blood pressure at the compression site by the second cuff attached at a place different from the first cuff,
The blood pressure measurement method according to claim 5 or 6, wherein blood pressures at different locations can be measured simultaneously. The blood pressure determination step includes
A third pulse wave signal detection step of detecting a pulse wave signal according to the first principle;
A fourth pulse wave signal detection step of detecting a pulse wave signal according to the second principle;
Based on the characteristics of the body motion obtained by the body motion detection step, the blood pressure value derived from the pulse wave detected by the third pulse wave signal detection step, or the fourth pulse wave signal detection step A second blood pressure value selecting step for selecting any of the blood pressure values derived from the pulse wave detected by
The blood pressure measurement method according to claim 7, comprising: A control program for executing a blood pressure measurement method,
A program code for executing a first pulse wave signal detection step of detecting a pulse wave signal at a compression site by the first cuff according to the first principle;
A program code for executing a second pulse wave signal detection step of detecting a pulse wave signal at a compression site by the first cuff according to a second principle;
A program code for executing a body motion detection step for detecting body motion;
A blood pressure value derived from the pulse wave detected by the first pulse wave signal detection step or the second pulse wave signal detection step based on the characteristics of the body motion obtained by the body motion detection step. And a program code for executing a blood pressure value selection step of selecting any one of the blood pressure values derived from the pulse wave detected by the control method. The body motion detection step includes
A level detection process for detecting the magnitude of body movement;
Including a cycle detection step of detecting a cycle of body movement,
The control program according to claim 9, wherein the characteristic of the body movement is at least one of the magnitude of the body movement detected by the level detection step and the period of the body movement detected by the cycle detection step. . Furthermore, it has a program code for executing a blood pressure determination step for determining a blood pressure at a site to be compressed by the second cuff, which is attached to a place different from the first cuff,
The control program according to claim 9 or 10, wherein blood pressure at different locations can be measured simultaneously. The blood pressure determination step includes
A third pulse wave signal detection step of detecting a pulse wave signal according to the first principle;
A fourth pulse wave signal detection step of detecting a pulse wave signal according to the second principle;
Based on the characteristics of the body motion obtained by the body motion detection step, the blood pressure value derived from the pulse wave detected by the third pulse wave signal detection step, or the fourth pulse wave signal detection step A second blood pressure value selecting step for selecting any of the blood pressure values derived from the pulse wave detected by
The control program according to claim 11, comprising: A computer-readable storage medium storing the control program according to any one of claims 9 to 12.

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