Blood pressure pulse wave inspection method and blood pressure pulse wave inspection device

Abstract

To provide a blood pressure pulse wave measuring method and a blood pressure pulse wave measuring device capable of measuring an appropriate pulse wave of a subject whose diastolic blood pressure is unknown.SOLUTION: A blood pressure pulse wave measuring method includes: a first cuff pressure control step of controlling the cuff pressure to a first target value; a first pulse wave measuring step of measuring the pulse wave of a subject when the cuff pressure is the first target value; a second cuff pressure control step of executing control to maintain the cuff pressure at the first target value, to raise the cuff pressure to a second target value larger than the first target value, or to lower the cuff pressure to a third target value smaller than the first target value, on the basis of the shape of the pulse wave measured in the first pulse wave measuring step; and a pulse wave recording step of recording the pulse wave measured in the state of the cuff pressure controlled in the second cuff pressure control step.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a blood pressure pulse wave testing method and blood pressure pulse wave testing device for non-invasively measuring blood pressure and pulse waves using a cuff. [Background technology]

[0002] Conventionally, the ratio of blood pressure measured in the lower and upper limbs (lower-to-upper limb blood pressure ratio) and pulse wave velocity (PWV) have been commonly used as indicators of vascular diseases such as arteriosclerosis and vascular blockage. Examples of lower-to-upper limb blood pressure ratios include the ratio of systolic blood pressure measured at the upper arm and ankle (ABI) and the ratio of systolic blood pressure measured at the upper arm and toe (TBI), and these are used as indicators of the presence or absence of arterial stenosis in the lower limbs.

[0003] On the other hand, PWV is the speed at which the pulse wave generated when blood is pumped from the heart to the aorta travels along the arterial wall, and the faster this speed is, the stiffer the blood vessels are. PWV is calculated by measuring the pulse wave and its transit time (PWT) at two points on the blood vessel and dividing the distance between these two points by the transit time.

[0004] Blood pressure pulse wave measuring devices capable of measuring PWV are described in Patent Documents 1 and 2, for example. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-164301 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-110155 Summary of the Invention [Problem to be solved by the invention]

[0006] The shape and amplitude of the pulse wave measured when the cuff is inflated changes depending on the applied pressure. For example, if the cuff pressure is too low, the pulse wave cannot be measured properly. Therefore, it is desirable to measure the pulse wave at a cuff pressure slightly below the diastolic blood pressure.

[0007] Because the cuff pressure required for blood pressure measurement is large, performing a single blood pressure measurement places a strain on the blood vessels, making it difficult to subsequently measure the pulse wave under natural vascular conditions. For this reason, pulse wave measurements are performed before blood pressure measurements. Therefore, because the individual's blood pressure is not known at the time of pulse wave measurement, pulse wave measurements have traditionally been performed at a cuff pressure slightly lower than the standard diastolic blood pressure, such as 50 mmHg.

[0008] However, it is known that diastolic blood pressure decreases with age and progression of arteriosclerosis, and in such subjects, 50 mmHg is lower than or close to the diastolic blood pressure, and the cuff may crush the blood vessels, making it impossible to obtain an appropriate pulse wave. Note that an appropriate pulse wave is one that has a shape suitable for determining PWV, CAVI (Cardio Ankle Vascular Index), etc.

[0009] The present invention has been made in consideration of the above points, and provides a blood pressure pulse wave testing method and blood pressure pulse wave testing device that can measure an appropriate pulse wave even for a subject whose diastolic blood pressure is unknown. [Means for solving the problem]

[0010] One aspect of the blood pressure pulse wave inspection method of the present invention includes: a first cuff pressure control step of controlling the cuff pressure to a first target value; a first pulse wave measuring step of measuring a pulse wave of the subject when the cuff pressure is at the first target value; a second cuff pressure control step of controlling the cuff pressure so as to maintain the cuff pressure at the first target value, increase the cuff pressure to a second target value greater than the first target value, or decrease the cuff pressure to a third target value less than the first target value, based on the shape of the pulse wave measured in the first pulse wave measurement step; a pulse wave recording step of recording a pulse wave measured under the cuff pressure controlled in the second cuff pressure control step; Includes:

[0011] One aspect of the blood pressure pulse wave inspection device of the present invention is a cuff to be attached to the subject; a cuff pressure control unit that controls a cuff pressure supplied to the cuff; a pulse waveform discriminator for discriminating a pulse waveform obtained by the cuff; a recording unit for recording pulse waves; Equipped with The cuff pressure control unit controls the cuff pressure to maintain the cuff pressure at the first target value, increase the cuff pressure to a second target value greater than the first target value, or decrease the cuff pressure to a third target value less than the first target value, based on the discrimination result obtained by the pulse wave shape discrimination unit when the cuff pressure is controlled to the first target value. [Effects of the Invention]

[0012] According to the present invention, it is possible to realize a blood pressure pulse wave testing method and blood pressure pulse wave testing device that can measure an appropriate pulse wave even for a subject whose diastolic blood pressure is unknown. [Brief explanation of the drawings]

[0013] [Figure 1] A graph illustrating the general relationship between cuff pressure and pulse wave amplitude. [Figure 2] Waveform diagram explaining the parameters required for measuring CAVI [Figure 3] 3A and 3B are diagrams showing examples of ideal pulse waveforms for performing CAVI measurement, in which FIG. 3A shows an ideal brachial pulse wave and FIG. 3B shows an ideal ankle pulse wave. [Figure 4] A waveform diagram showing an example in which the rising point of the pulse wave is unclear due to the subject's low blood pressure. [Figure 5] A waveform diagram showing an example of a pulse wave whose rising edge is unclear due to excessively high cuff pressure and tightness. [Figure 6]Waveform diagram showing an example where the notch of the pulse wave is unclear and cannot be measured [Figure 7] FIG. 1 is a block diagram showing the overall configuration of a blood pressure pulse wave inspection device according to an embodiment. [Figure 8] FIG. 1 is a block diagram showing the main configuration for implementing cuff pressure optimization processing during pulse wave measurement according to an embodiment. [Figure 9] 1 is a flowchart showing a conventional cuff pressure control process during pulse wave measurement, as a comparative example of the embodiment. [Figure 10] 1 is a flowchart showing the procedure for optimizing cuff pressure during pulse wave measurement according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] <1> How the invention came about Before describing the embodiments of the present invention, the background to the invention will be described.

[0015] Figure 1 is a graph illustrating the general relationship between cuff pressure and pulse wave amplitude. From Figure 1, it can be seen that a cuff pressure of 65 mmHg allows measurement of a pulse wave with a larger amplitude than a cuff pressure of 50 mmHg.

[0016] Figure 2 is a waveform diagram explaining the parameters required to measure the Cardio Ankle Vascular Index (CAVI), an index of arteriosclerosis. CAVI measurement uses haPWV (= Lha (vascular length) / T (time)). The time (T) from the opening of the aortic valve to the onset of the ankle pulse wave is used to calculate haPWV. However, since it is difficult to determine the point in time when the aortic valve opens from the first heart sound, the second heart sound is used instead.

[0017] In practice, the parameters shown in Figure 2 are used for CAVI measurement. The parameters tb, t'b, and tba in the figure indicate the following times: tb: Time from the second heart sound to the notch of the brachial pulse wave t'b: Time from aortic valve opening to brachial pulse rise tba: Brachial pulse wave upstroke time to ankle pulse wave upstroke time

[0018] In CAVI measurement, tb and t'b are considered to be the same. The time T used in calculation is the sum of t'b and tba, and can be obtained from heart sounds, brachial pulse waves, and ankle pulse waves. CAVI measurement is a known technique described in Patent Document 2, etc., and therefore a detailed description thereof will be omitted here.

[0019] As can be seen from the above, in order to measure CAVI accurately, the notch and rising edge of the pulse wave must be clearly defined.

[0020] 3A and 3B are diagrams showing examples of ideal pulse waveforms for CAVI measurement. Fig. 3A shows an ideal brachial pulse wave, with a clear notch and a clear rising edge of the pulse wave. Fig. 3B shows an ideal ankle pulse wave, with a clear rising edge of the pulse wave.

[0021] 4, 5 and 6 are diagrams showing examples in which a pulse wave with an appropriate shape was not obtained when the pulse wave was measured at a cuff pressure of 50 mmHg.

[0022] Figure 4 is a waveform diagram showing an example in which the rising edge of the pulse wave is unclear due to the subject's low blood pressure. As can be seen from Figure 4, low blood pressure can cause a drop in the waveform before the rising edge, resulting in a two-step rising edge. In such cases, the rising edge of the pulse wave becomes unclear.

[0023] The inventors of the present invention considered that for subjects with such low blood pressure (i.e., subjects with a two-step rising waveform), a cuff pressure of 65 mmHg would allow a pulse wave with a larger amplitude to be measured than a cuff pressure of 50 mmHg, as shown in Figure 1. This would allow a pulse wave with a clearer rising position to be obtained.

[0024] Figure 5 is a waveform diagram showing an example in which the cuff pressure is too high and the blood vessels are compressed during the diastolic phase, causing the pulse wave to become flat during the diastolic phase, resulting in an unclear rising edge of the pulse wave. In the case of Figure 5, the rising edge of the pulse wave is unclear compared to the ideal pulse wave shape shown in Figure 3.

[0025] The inventors of the present invention thought that if such a waveform is obtained (i.e., if a pulse wave with a flat diastole is obtained), the waveform could be improved by reducing the cuff pressure to 30 mmHg to improve blood flow.

[0026] FIG. 6 is a waveform diagram showing an example in which the notch of the pulse wave is unclear and cannot be measured.

[0027] The inventors of the present invention have found that applying a cuff pressure equal to or higher than the systolic blood pressure reduces the influence of reflected waves from the periphery, resulting in a clearer notch. In the case shown in Figure 6, the cuff pressure is increased to systolic blood pressure + 30 mmHg to measure the pulse wave. This allows for a pulse wave with a clearer notch to be obtained.

[0028] Based on this consideration, in the present invention, instead of measuring pulse waves at a fixed cuff pressure of 50 mmHg, which is slightly lower than the standard diastolic blood pressure, if an inappropriate pulse wave is obtained, the cuff pressure is adaptively changed according to the shape of the pulse wave. This makes it possible to measure an appropriate pulse wave even for subjects whose diastolic blood pressure is unknown.

[0029] <2> Embodiment Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0030] <2-1> Overall configuration of blood pressure pulse wave inspection device FIG. 7 is a block diagram showing the overall configuration of a blood pressure pulse wave inspecting device according to an embodiment of the present invention.

[0031] In Figure 7, the main body 1a of the blood pressure pulse wave inspection device 1 is provided with an arithmetic processing unit 10, an input unit 70, a display unit 80, a display control unit 81, a printing unit 91, a memory unit 92, an audio output unit 93, a blood pressure pulse wave measuring unit 30, a heart sound measuring unit 40, an electrocardiogram measuring unit 50, and a pulse wave measuring unit 60.

[0032] The blood pressure pulse wave measurement unit 30 has an upper arm measurement control unit 31 and a lower limb measurement control unit 32. A right upper arm cuff 21R and a left upper arm cuff 21L are connected to the upper arm measurement control unit 31 via hoses 21h, and a right ankle cuff 22R and a left ankle cuff 22L are connected to the lower limb measurement control unit 32 via hoses 22h.

[0033] The blood pressure pulse wave measuring unit 30 has an oscillometric blood pressure measuring function and an air-bag pulse wave measuring function.

[0034] The upper limb measurement control unit 31 includes a pressure sensor 33, a signal processing circuit that performs predetermined signal processing such as amplification on the detection signal from the pressure sensor 33, a pump and exhaust valve that supply and exhaust air to and from the cuffs 21R and 21L, and a computer that controls the supply and exhaust operation and has a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), various interfaces, etc. The upper limb measurement control unit 31 increases the internal pressure of the cuffs 21R and 21L (hereinafter, the internal pressure of the cuffs is referred to as "cuff pressure") by introducing air into the rubber bladders of the cuffs 21R and 21L via the hose 21h, and decreases the cuff pressure of the cuffs 21R and 21L by discharging air from the rubber bladders. The cuff 21R is attached to the subject's right upper arm, and the cuff 21L is attached to the subject's left upper arm. The target values ​​of the cuff pressure after inflation differ for pulse wave measurement and blood pressure measurement and can be set separately for each.

[0035] In the case of pulse wave measurement, upper limb measurement control unit 31 detects fluctuations in the cuff pressure of cuffs 21R, 21L after inflation as a pulse wave signal using pressure sensor 33, and outputs the detected pulse wave signal to calculation processing unit 10. Pulse wave measurement is performed in response to a request from calculation processing unit 10. Note that only one or both of two cuffs 21R, 21L may be used for pulse wave measurement.

[0036] In the case of blood pressure measurement, the upper limb measurement control unit 31 detects the vibration of the cuff pressure of the cuffs 21R and 21L during decompression using the pressure sensor 33, and detects the cuff pressure with the most significant increase in amplitude as the systolic blood pressure, and detects the cuff pressure with the most significant decrease in vibration as the diastolic blood pressure. The upper limb measurement control unit 31 then outputs blood pressure signals indicating the detected systolic blood pressure and diastolic blood pressure to the calculation processing unit 10. Blood pressure measurement is performed in response to a request from the calculation processing unit 10. When a request is received from the calculation processing unit 10, right blood pressure measurement using only the cuff 21R and left blood pressure measurement using only the cuff 21L are usually performed sequentially, but these blood pressure measurements may also be performed in parallel.

[0037] The lower limb measurement control unit 32 includes a pressure sensor 34, a signal processing circuit that performs predetermined signal processing, such as amplification, on the detection signal from the pressure sensor 34, a pump and exhaust valve that supply and exhaust air to and from the cuffs 22R and 22L, and a computer having a CPU, ROM, RAM, various interfaces, etc. that controls this supply and exhaust operation. The lower limb measurement control unit 32 increases the cuff pressure of the cuffs 22R and 22L by introducing air into the rubber bladders of the cuffs 22R and 22L via the hose 22h, and decreases the cuff pressure of the cuffs 22R and 22L by exhausting air from the rubber bladders. The cuff 22R is attached to the subject's right ankle, and the cuff 22L is attached to the subject's left ankle. The target values ​​for the cuff pressure after inflation differ for pulse wave measurement and blood pressure measurement and can be set separately for each. The operation of the lower limb measurement control unit 32 when measuring pulse waves and blood pressure is the same as that of the upper limb measurement control unit 31, and therefore a detailed description thereof will be omitted here.

[0038] The computers of the upper limb measurement control section 101 and the lower limb measurement control section 32 execute a control program stored in the ROM by the CPU, thereby performing calculations for blood pressure pulse wave measurement, which will be described below.

[0039] In this embodiment, the blood pressure pulse wave measurement unit 30 is configured by independently providing an upper limb measurement control unit 31 and a lower limb measurement control unit 32, but the upper limb measurement control unit 31 and the lower limb measurement control unit 32 may also be integrated.

[0040] A heart sound microphone 23 is connected to the heart sound measurement unit 40. A four limb electrocardiogram electrode unit 24a and a chest electrocardiogram electrode unit 24b are connected to the electrocardiogram measurement unit 50. Amorphous pulse wave sensors 25a and 25b are connected to the pulse wave measurement unit 60.

[0041] The arithmetic processing unit 10 is a computer having a CPU, a ROM, a RAM, various interfaces, etc. The arithmetic control unit 10 executes a control program stored in the ROM by the CPU.

[0042] The calculation processing unit 10 controls the blood pressure pulse wave measuring unit 30, the heart sound measuring unit 40, the electrocardiogram measuring unit 50, and the pulse wave measuring unit 60 (hereinafter, these are referred to as "each biological information measuring unit").

[0043] The arithmetic processing unit 10 also receives biological information supplied from each biological information measurement unit. When the received biological information needs to be displayed on a screen, it edits or converts it into display data and outputs it to the display unit 80, and when it needs to be printed on report paper, it edits or converts it into print data and outputs it to the print unit 91. The arithmetic processing unit 10 also stores the received biological information in the storage unit 92 and reads out the stored biological information as appropriate.

[0044] The calculation processing unit 10 also performs waveform analysis of the biological information received from each biological information measurement unit. In the waveform analysis, characteristic parts (dividing points) in the waveform are detected. Examples of characteristic parts include the start of the second heart sound, the rising edge of the pulse wave at the upper arm, the rising edge of the pulse wave at the ankle, a notch in the pulse wave, and a notch in the pulse wave at the upper arm.

[0045] The arithmetic processing unit 10 calculates the degree of arteriosclerosis based on the analysis result and the value (for example, blood pressure) indicated by the received biological information.

[0046] A more detailed description will be given. The calculation processing unit 10 calculates the brachial-ankle pulse wave velocity (baPWV) and the heart-ankle arterial pulse wave velocity (haPWV) as pulse wave velocities, and also calculates the ankle-brachial pressure index (ABI) as a lower limb / upper limb blood pressure index. That is, the calculation processing unit 10 calculates the ankle-brachial pressure index (ABI) and pulse wave velocity (PWV) using the pulse wave detected by the blood pressure pulse wave measuring unit 30. The calculation control unit 10 also calculates the subject's blood pressure value using the pulse wave detected by the blood pressure pulse wave measuring unit 30. The calculation control unit 10 also calculates indices such as the cardio-ankle vascular index (CAVI) calculated based on the heart-ankle arterial pulse wave velocity (haPWV). Here, the calculation control unit 10 calculates CAVI by correcting the heart-ankle arterial pulse wave velocity haPWV with a logarithmic pulse wave. As is known, the brachial-ankle pulse wave velocity baPWV and the heart-ankle arterial pulse wave velocity haPWV are indicators of vascular stiffness, and the ankle-brachial blood pressure index ABI is an indicator of vascular clogging.

[0047] In addition, the calculation processing unit 10 receives inputs and instructions from the input unit 70 through user operations, and in accordance with the received contents, performs settings related to the functions of each biometric information measurement unit, display unit 80, printing unit 91, memory unit 92 and audio output unit 93, and controls the start and stop of each operation.

[0048] The display unit 80 is a display device having a display screen such as an LCD (Liquid Crystal Display), and displays on the screen the biological information, analysis results, arteriosclerosis degree, etc. input from the arithmetic processing unit 10 as display data.

[0049] The printing unit 91 has as its main components a paper feed mechanism, a printing head, etc., and prints on paper the biological information, analysis results, and arteriosclerosis degree input as printing data from the arithmetic processing unit 10.

[0050] The storage unit 92 is configured with a hard disk drive, a writable optical disk drive, a nonvolatile memory, etc., and is capable of storing information from the calculation processing unit 10. The storage unit 92 also records biological information measured by each biological information measurement unit, that is, an electrocardiogram, a pulse wave, and heart sounds.

[0051] The audio output unit 93 has a speaker or the like as its main component, and outputs a guidance voice or an alert sound or the like in accordance with the guidance data or the alert sound output instruction signal input from the calculation processing unit 10.

[0052] The input unit 70 is composed of a keyboard, a mouse, buttons, a touch panel, etc., and receives inputs and instructions from the user and sends them to the arithmetic processing unit 10.

[0053] Pulse wave measuring unit 60 supplies the subject's pulse wave signals detected by amorphous pulse wave sensors 25a, 25b appropriately attached to the subject to calculation processing unit 10. This allows measurement and analysis of the pulse wave. Note that one of amorphous pulse wave sensors 25a, 25b is attached, for example, to the subject's carotid artery, and the other is attached, for example, to the subject's femoral artery or knee.

[0054] The electrocardiogram measurement unit 50 supplies electrocardiogram signals detected by the four limb electrocardiogram electrodes 24a and chest electrocardiogram electrodes 24b attached to the subject to the arithmetic processing unit 10. This allows electrocardiogram measurement and analysis. The four limb electrocardiogram electrodes 24a typically consist of four electrocardiogram electrodes attached to the right wrist, left wrist, right ankle, and left ankle, respectively. The electrocardiogram electrodes for both ankles are preferably configured so that their attachment to both ankles is not obstructed by the right ankle cuff 22R and left ankle cuff 22L. The chest electrocardiogram electrode unit 25b typically consists of six electrocardiogram electrodes attached to six locations on the chest.

[0055] The heart sound measurement unit 40 supplies the heart sound signal detected by the heart sound microphone 23 attached to the subject to the calculation processing unit 10. In this way, the heart sounds are measured and analyzed.

[0056] <2-2> Cuff pressure optimization process during pulse wave measurement according to this embodiment 8 is a block diagram showing the configuration of the main part for realizing the cuff pressure optimization process during pulse wave measurement according to this embodiment. In practice, the configuration of FIG. 8 is provided in blood pressure pulse wave measurement unit 30.

[0057] The cuff pressure control unit 101 controls the cuff pressure supplied to the cuff. Specifically, the cuff pressure control unit 101 controls the pumps and exhaust valves of the upper limb measurement control unit 31 and the lower limb measurement control unit 32 to control the cuff pressure.

[0058] The pulse waveform discriminator 102 receives pulse wave signals obtained by the pressure sensors 33 and 34 and the signal processing circuits of the upper limb measurement controller 31 and the lower limb measurement controller 32, and discriminates the pulse waveform. The pulse waveform discriminator 102 outputs the discrimination result to the cuff pressure controller 101.

[0059] The cuff pressure control unit 101 controls the cuff pressure during pulse wave measurement based on the discrimination result from the pulse wave shape discriminator 102 .

[0060] The recording unit 103 receives the pulse wave signals obtained by the pressure sensors 33, 34 and the signal processing circuits of the upper limb measurement control unit 31 and the lower limb measurement control unit 32, and records the pulse wave signals. The recording unit 103 may be provided in the calculation processing unit 10. The pulse wave signals recorded in the recording unit 103 are used to calculate baPWV, haPWV, CAVI, etc.

[0061] Next, a cuff pressure optimization process during pulse wave measurement according to this embodiment will be described.

[0062] First, a conventional cuff pressure control process during pulse wave measurement will be described as a comparative example of this embodiment with reference to FIG.

[0063] When the start button for pulse wave measurement is pressed in step S11, the process moves to step S12, where the cuff is inflated to a target pressure of 50 mmHg (a cuff pressure slightly lower than the average diastolic blood pressure).

[0064] In the following step S13, after the pulse wave has stabilized, measurement of the pulse wave begins, and in step S14, the pulse wave is recorded.

[0065] In the next step S15, after the recording period has elapsed, the pulse wave measurement is terminated and cuff deflation is initiated. In the next step S16, when the cuff pressure reaches atmospheric pressure, all measurements using the cuff, including blood pressure measurement, are completed.

[0066] 10 is a flowchart showing the procedure for optimizing the cuff pressure during pulse wave measurement according to this embodiment. The following procedure is implemented by a computer provided in blood pressure pulse wave measurement unit 30 and arithmetic processing unit 10 executing a program.

[0067] When the start button for pulse wave measurement is pressed in step S21, the blood pressure pulse wave inspection device 1 proceeds to step S22, where the cuff pressure control unit 101 inflates the cuffs 21R, 21L, 22R, and 22L to a target cuff pressure of 50 mmHg (a cuff pressure slightly lower than the standard diastolic blood pressure).

[0068] In the following step S23, blood pressure pulse wave measuring unit 30 starts measuring the pulse wave after confirming that the pulse wave has stabilized.

[0069] In the next step S24, blood pressure pulse wave measurement unit 30 determines whether the leg pulse wave has a two-stage rising edge. Specifically, pulse wave shape determination unit 102 determines whether the leg pulse wave measured by cuffs 22R, 22L attached to the legs has a two-stage rising edge, as shown in FIG.

[0070] If the blood pressure pulse wave measurement unit 30 determines in step S24 that the rising edge of the pulse wave has two stages, the process proceeds to step S25, where the cuff pressure of the leg is increased to a target of 65 mmHg, while the arm pressure remains unchanged. Specifically, the cuff pressure control unit 101 controls the cuff pressure of the cuffs 22R and 22L to 65 mmHg. As described above, if the rising edge of the pulse wave is unclear due to low blood pressure of the subject, increasing the cuff pressure makes it possible to obtain a pulse wave with a larger amplitude, thereby obtaining a pulse wave with a clearer rising edge.

[0071] In the following step S26, blood pressure pulse wave measuring unit 30 starts measuring the pulse wave after confirming that the pulse wave has stabilized.

[0072] On the other hand, if blood pressure pulse wave measurement unit 30 determines in step S24 that the rising waveform does not have two stages, the process proceeds to step S27, where it determines whether the arm pulse wave is flat. Specifically, pulse wave waveform determination unit 102 determines whether the shape of the arm pulse wave measured by cuffs 21R and 21L attached to the arm is flatter in diastole than a predetermined shape, as shown in FIG. 5. The predetermined shape is, for example, the shape of a standard arm pulse wave. The determination of whether the pulse wave is flat may be made, for example, by determining whether the difference in slope of the diastolic pulse wave from the standard arm wave is equal to or greater than a predetermined value.

[0073] If the blood pressure pulse wave measurement unit 30 determines in step S27 that the diastolic pulse wave is flatter than the predetermined shape, the process proceeds to step S28, where the cuff pressure of the arm is reduced to a target of 30 mmHg, while the leg is left as is. Specifically, the cuff pressure control unit 101 controls the cuff pressure of cuffs 21R and 21L to 30 mmHg. As described above, if the cuff pressure is too high and the cuff is too tight, causing the rising edge of the pulse wave to become unclear, reducing the cuff pressure improves the blood flow, resulting in a pulse wave with a clearer rising edge.

[0074] In the following step S29, blood pressure pulse wave measuring unit 30 starts measuring the pulse wave after confirming that the pulse wave has stabilized.

[0075] On the other hand, if blood pressure pulse wave measurement unit 30 determines in step S27 that the arm pulse wave is not flat, the process proceeds to step S30, where it determines whether or not there is a notch in the arm pulse wave. Specifically, pulse wave shape determination unit 102 determines whether or not there is a notch in the shape of the arm pulse wave measured by cuff 21R or 21L attached to the arm, at a position as shown in Fig. 6. Here, whether or not there is a notch can be rephrased as whether or not the notch is unclear.

[0076] If the blood pressure pulse wave measurement unit 30 determines in step S30 that there is no notch, the process proceeds to step S31, where it increases only the arm cuff pressure to above the systolic blood pressure (for example, systolic blood pressure + 30 mmHg) while leaving the leg in place. Specifically, the cuff pressure control unit 101 controls the cuff pressure of the cuff 21R or 21L to be above the systolic blood pressure. As described above, this reduces the influence of reflected waves from the periphery, allowing a pulse wave with a clearer notch to be obtained. The systolic blood pressure here may be, for example, the standard systolic blood pressure.

[0077] In the following step S32, the blood pressure pulse wave measuring unit 30 starts measuring the pulse wave after confirming that the pulse wave has stabilized.

[0078] In step S33, blood pressure pulse wave inspection device 1 records the pulse waves measured in steps S23, S26, S29, and S32 in recording unit 103. That is, the pulse waves used for CAVI measurement are recorded. In the following step S34, blood pressure pulse wave measurement unit 30 ends pulse wave measurement after the recording period has elapsed and starts cuff deflation. In the following step S35, when the cuff pressure reaches atmospheric pressure, blood pressure pulse wave measurement unit 30 completes all measurements using the cuff, including blood pressure measurement.

[0079] <3> summary As described above, the blood pressure pulse wave inspection device 1 of this embodiment includes cuffs 21R, 21L, 22R, and 22L attached to the subject, a cuff pressure control unit 101 that controls the cuff pressure supplied to cuffs 21R, 21L, 22R, and 22L, a pulse wave shape discrimination unit 102 that discriminates the pulse wave shape obtained by cuffs 21R, 21L, 22R, and 22L, and a recording unit 103 that records the pulse wave.The cuff pressure control unit 101 controls the cuff pressure based on the discrimination result obtained by the pulse wave shape discrimination unit 102 when the cuff pressure is controlled to a first target value (e.g., 50 mmHg), to maintain the cuff pressure at the first target value (e.g., 50 mmHg), or to increase the cuff pressure to a second target value greater than the first target value (e.g., 65 mmHg or higher than the systolic blood pressure), or to decrease the cuff pressure to a third target value less than the first target value (e.g., 30 mmHg).

[0080] This makes it possible to realize a blood pressure pulse wave examination method and blood pressure pulse wave examination device 1 that can measure an appropriate pulse wave even for a subject whose diastolic blood pressure is unknown.

[0081] The above-described embodiments are merely examples of specific embodiments of the present invention, and the technical scope of the present invention should not be construed as being limited by these embodiments. In other words, the present invention can be embodied in various forms without departing from the gist or main characteristics thereof.

[0082] The specific values ​​of the cuff pressure in the above-mentioned embodiments are merely examples and can be modified in various ways. The blood pressure pulse wave testing method of the present invention may essentially include a first cuff pressure control step of controlling the cuff pressure to a first target value, a first pulse wave measurement step of measuring the pulse wave of the subject when the cuff pressure is at the first target value, a second cuff pressure control step of controlling the cuff pressure to maintain the cuff pressure at the first target value, or to increase it to a second target value greater than the first target value, or to decrease it to a third target value less than the first target value, based on the shape of the pulse wave measured in the first pulse wave measurement step, and a pulse wave recording step of recording the pulse wave measured at the cuff pressure controlled in the second cuff pressure control step. [Industrial Applicability]

[0083] The present invention is widely applicable to blood pressure pulse wave testing methods and blood pressure pulse wave testing devices that measure blood pressure and pulse waves non-invasively using a cuff. [Explanation of symbols]

[0084] 1. Blood pressure pulse wave testing device 10. Processing unit 21R, 21L, 22R, 22L Cuff 30 Blood pressure pulse wave measurement unit 31 Upper limb measurement control unit 32 Lower limb measurement control unit 33, 34 Pressure sensor 101 Cuff pressure control unit 102 Pulse wave shape determination section 103 Recording Section

Claims

1. a first cuff pressure control step of controlling the cuff pressure to a first target value; a first pulse wave measuring step of measuring a pulse wave of the subject when the cuff pressure is at the first target value; a second cuff pressure control step of controlling the cuff pressure so as to maintain the cuff pressure at the first target value, increase the cuff pressure to a second target value greater than the first target value, or decrease the cuff pressure to a third target value less than the first target value, based on the shape of the pulse wave measured in the first pulse wave measurement step; a pulse wave recording step of recording a pulse wave measured under the cuff pressure controlled in the second cuff pressure control step; Including, In the second cuff pressure control step, when the rising shape of the measured pulse wave has two steps, the cuff pressure is increased to the second target value. Blood pressure pulse wave testing method.

2. A first cuff pressure control step of controlling the cuff pressure to a first target value; a first pulse wave measuring step of measuring a pulse wave of the subject when the cuff pressure is at the first target value; a second cuff pressure control step of controlling the cuff pressure so as to maintain the cuff pressure at the first target value, increase the cuff pressure to a second target value greater than the first target value, or decrease the cuff pressure to a third target value less than the first target value, based on the shape of the pulse wave measured in the first pulse wave measurement step; a pulse wave recording step of recording a pulse wave measured under the cuff pressure controlled in the second cuff pressure control step; Including, In the second cuff pressure control step, when a diastolic pulse wave shape measured by a cuff attached to the arm is flat compared with a predetermined shape, the cuff pressure of the cuff attached to the arm is decreased to the third target value. Blood pressure pulse wave testing method.

3. A first cuff pressure control step of controlling the cuff pressure to a first target value; a first pulse wave measuring step of measuring a pulse wave of the subject when the cuff pressure is at the first target value; a second cuff pressure control step of controlling the cuff pressure so as to maintain the cuff pressure at the first target value, increase the cuff pressure to a second target value greater than the first target value, or decrease the cuff pressure to a third target value less than the first target value, based on the shape of the pulse wave measured in the first pulse wave measurement step; a pulse wave recording step of recording a pulse wave measured under the cuff pressure controlled in the second cuff pressure control step; Including, In the second cuff pressure control step, when a notch in the shape of the arm pulse wave measured by the cuff attached to the arm is smaller than a predetermined shape, the cuff pressure of the cuff attached to the arm is increased to the second target value. Blood pressure pulse wave testing method.

4. The cuff whose cuff pressure is controlled is composed of a plurality of cuffs attached to at least the subject's legs and arms. The blood pressure pulse wave inspection method according to any one of claims 1 to 3.

5. a cuff to be attached to the subject; a cuff pressure control unit that controls a cuff pressure supplied to the cuff; a pulse waveform discriminator for discriminating a pulse waveform obtained by the cuff; a recording unit for recording pulse waves; Equipped with the cuff pressure control unit controls the cuff pressure to maintain the cuff pressure at the first target value, or to increase the cuff pressure to a second target value greater than the first target value, or to decrease the cuff pressure to a third target value less than the first target value, based on a discrimination result obtained by the pulse wave shape discriminator when the cuff pressure is controlled to the first target value; The pulse wave shape determining unit determines whether or not there is a drop before the rise in the shape of the leg pulse wave, whether or not the diastolic pulse wave of the brachial pulse wave is flat compared to a predetermined shape, or whether or not the notch of the brachial pulse wave is unclear. Blood pressure pulse wave testing device.

6. A cuff attached to a subject; a cuff pressure control unit that controls a cuff pressure supplied to the cuff; a pulse waveform discriminator for discriminating a pulse waveform obtained by the cuff; a recording unit for recording pulse waves; Equipped with the cuff pressure control unit controls the cuff pressure to maintain the cuff pressure at the first target value, or to increase the cuff pressure to a second target value greater than the first target value, or to decrease the cuff pressure to a third target value less than the first target value, based on a determination result obtained by the pulse wave shape determination unit when the cuff pressure is controlled to the first target value; When the pulse wave shape discriminator determines that the rising shape of the pulse wave has two steps, the cuff pressure of the cuff is increased to the second target value. Blood pressure pulse wave testing device.

7. A cuff attached to a subject; a cuff pressure control unit that controls a cuff pressure supplied to the cuff; a pulse waveform discriminator for discriminating a pulse waveform obtained by the cuff; a recording unit for recording pulse waves; Equipped with the cuff pressure control unit controls the cuff pressure to maintain the cuff pressure at the first target value, or to increase the cuff pressure to a second target value greater than the first target value, or to decrease the cuff pressure to a third target value less than the first target value, based on a determination result obtained by the pulse wave shape determination unit when the cuff pressure is controlled to the first target value; When the pulse wave shape discriminator discriminates that the diastolic pulse wave shape of the arm pulse wave is flat compared with a predetermined shape, the cuff pressure of the cuff attached to the arm is reduced to the third target value. Blood pressure pulse wave testing device.

8. A cuff attached to a subject; a cuff pressure control unit that controls a cuff pressure supplied to the cuff; a pulse waveform discriminator for discriminating a pulse waveform obtained by the cuff; a recording unit for recording pulse waves; Equipped with the cuff pressure control unit controls the cuff pressure to maintain the cuff pressure at the first target value, or to increase the cuff pressure to a second target value greater than the first target value, or to decrease the cuff pressure to a third target value less than the first target value, based on a determination result obtained by the pulse wave shape determination unit when the cuff pressure is controlled to the first target value; When the pulse wave shape discriminator determines that the shape of the arm pulse wave has a smaller notch than a predetermined shape, the cuff pressure of the cuff attached to the arm is increased to the second target value. Blood pressure pulse wave testing device.

9. The cuff is composed of a plurality of cuffs attached to at least the subject's legs and arms. The blood pressure pulse wave inspection device according to any one of claims 5 to 8.

10. The second target value is a value equal to or greater than the systolic blood pressure. The blood pressure pulse wave inspection device according to any one of claims 5 to 8.

11. CAVI (Cardio Ankle Vascular Index) is calculated using the leg pulse wave and arm pulse wave recorded in the recording unit. The blood pressure pulse wave inspection device according to any one of claims 5 to 8.

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