JPH01214339A - Blood pressure monitoring method and apparatus - Google Patents

Abstract

PURPOSE:To sufficiently obtain the measuring accuracy of blood pressure and to alleviate the pain given to a living body by correcting the preliminarily calculated relation between the pulse wave detected by a pulse wave sensor and a blood pressure value on the basis of an actual blood pressure value and a pulse wave simultaneously with the measurement of the actual blood pressure value. CONSTITUTION:A pressure sensor 14 detects the pressure in a cuff 10 to output a cuff pressure signal SP showing the cuff pressure P to a CPU 24. The CPU 24 determines the cuff pressure P as maximal and minimal blood pressures on the basis of a pulse sound signal SO and the cuff pressure signal SP. A pulse wave sensor 32 detects a pulse wave from the radial artery to supply a pulse wave signal SM showing said pulse wave to the CPU 24 through an A/D converter 34. On the basis of the pulse wave detected when a blood pressure value is determined, the corresponding relation between the blood pressure value and the pulse wave is corrected at each time when an actual blood pressure value is detected. Therefore, the corresponding relation between the blood pressure value and the pulse wave is always accurately obtained and the measuring accuracy of blood pressure is sufficiently obtained. Since a blood pressure value is monitored only by pressing a part of a living body at a definite time interval, the pain given to the living body is alleviated to a large extent.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a blood pressure monitoring method and apparatus for monitoring a blood pressure value based on a pulse wave detected by a pulse wave sensor based on a predetermined relationship.

Conventional technology and its problems In general, when measuring blood pressure, a part of the living body is compressed with a cuff, etc., and pressure vibration waves (pulse waves) of the cuff that are generated in synchronization with the living body's heartbeat are detected and the pressure is measured. Blood pressure values are determined based on changes in the magnitude of vibration waves.

However, when such a method is used for a living body whose blood pressure needs to be continuously monitored over a long period of time, such as a patient after surgery, a part of the living body is continuously compressed for a long time. It causes considerable pain to living organisms.

First Means for Solving the Problems Against the background of the above-mentioned circumstances, the present invention aims to provide a blood pressure monitoring method in which the discomfort caused to a living body when monitoring the blood pressure of the living body is significantly reduced. The purpose of this method is to provide a blood pressure monitoring method for monitoring the blood pressure of a living body based on a pulse wave detected by a pulse wave sensor based on a predetermined relationship, )
a blood pressure measurement step that includes a cuff for compressing a part of the living body and measures the blood pressure value of the living body by compressing the cuff; With the pulse wave detected by the pulse wave sensor when the cuff is compressing with the same pressure,
and a correction step in which the relationship is corrected.

Operation and Effect of the First Invention With this method, the actual blood pressure value of the living body is measured in the blood pressure measurement process, and at the same time, the predetermined difference between the pulse wave detected by the pulse wave sensor and the blood pressure value is measured. The relationship is corrected by the actual blood pressure value and the pulse wave when the actual blood pressure value was measured, and the blood pressure value is determined based on the pulse wave from the thus corrected relationship.

Therefore, according to the present invention, the blood pressure value is determined based on the pulse wave from the relationship corrected by, for example, measuring the actual blood pressure value at regular intervals in the blood pressure measurement process. Even when continuously monitoring the blood pressure value of a living body over time, it is not necessary to continuously compress a part of the living body to determine the blood pressure value.
This prevents the blood circulation of the living body from being inhibited, and the pain inflicted on the living body is greatly reduced. In addition, each time the actual blood pressure value is detected, the correspondence between the blood pressure value and the pulse wave is corrected based on the pulse wave detected when the blood pressure value was determined, so the correspondence between the blood pressure value and the pulse wave is corrected. The relationship can always be accurately obtained, and blood pressure measurement can be performed with sufficient accuracy.

Second Means for Solving the Problem Another aspect of the present invention is to determine the blood pressure value of a living body based on a pulse wave detected by a pulse wave sensor from a predetermined relationship. A blood pressure value determination means is provided,
A blood pressure monitoring device that monitors the blood pressure value of a living body based on the blood pressure value determined by the blood pressure value determining means,
(1) a blood pressure measuring means having a cuff for compressing a part of a living body and measuring the blood pressure value of the living body by compressing the cuff; (b) a blood pressure value determined by the blood pressure measuring means; The pulse wave detected by the pulse wave sensor when the cuff is compressing at the same pressure as the value,
and a correction means for correcting the relationship.

Operation and Effect of the Second Invention With this arrangement, as shown in the claim correspondence diagram of FIG. The predetermined relationship between the wave and the blood pressure value is corrected by the correction means by the actual blood pressure value and the pulse wave detected when the actual blood pressure value is measured, and is thus corrected. From this relationship, the blood pressure value is determined by the blood pressure value determining means based on the pulse wave.

Therefore, by using the device of the present invention, the blood pressure value can be determined based on the pulse wave from the relationship corrected by, for example, measuring the actual blood pressure value in advance or at regular intervals by the blood pressure measuring means. Therefore, even when the blood pressure value of the living body is continuously monitored over a long period of time, there is no need to continuously compress a part of the living body in order to determine the blood pressure value. Similarly, the blood circulation of the living body is prevented from being inhibited, and the pain inflicted on the living body is significantly reduced. Furthermore, in the present invention, the correspondence between the blood pressure value and the pulse wave is corrected each time the actual blood pressure value is detected based on the pulse wave detected when the blood pressure value was determined. Sufficient accuracy can be obtained.

Embodiments Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 is a diagram illustrating the configuration of the blood pressure monitoring device of this embodiment. In the figure, a rubber bag-shaped cuff 10 that is wrapped around and compresses the upper arm of a living body has a microphone inside. 12 are provided. In addition, the cuff 10 has
Pressure sensor 14. Switching valve 16. and an electric pump 18 are connected to each other via piping 19. The microphone 12 detects pulse sounds (Korotkoff sounds) generated from the upper arm of the living body, and supplies a pulse sound signal SO representing the pulse sounds to the bandpass filter 20 . The band pass filter 20 passes a signal having a frequency component of, for example, about 30 to 80 Hz, and converts the passed pulse sound signal SO into an A/
It is supplied to the CPU 24 via the D converter 22. The pressure sensor 14 detects the pressure within the cuff 10 (cuff pressure P) and outputs a cuff pressure signal SP representing the cuff pressure P to the CPU 24.

The switching valve 16 is used to adjust the cuff pressure P by switching between three states: a pressure supply state, a rate-limiting evacuation state, and a rapid evacuation state between the cuff 10 and the electric pump 18. That is,
In the pressure supply state, the rate-limiting exhaust port and rapid exhaust port of the switching valve 16 are closed, pressure is supplied from the electric pump 18 to the cuff 10, and when the cuff pressure P reaches a predetermined target cuff pressure, rate-limiting exhaust is performed. The inside of the cuff 10 is evacuated from the rate-limiting exhaust port equipped with a restriction at a predetermined speed suitable for predetermined blood pressure measurement.
At the same time as the blood pressure is measured during the rate-determining blood pressure lowering period, the state is switched to the rapid evacuation state, and the inside of the cuff 10 is rapidly evacuated from the rapid evacuation port.

The CPU 24 connects the ROM 26 .
RAM28. Connected to I10 port 27, RO
RAM28 according to the program stored in advance in M26
Execute signal processing while using the temporary memory function of 0N10F to drive circuit 31 connected to electric pump 18.
Controlling the start and stop of the electric pump 18 by supplying the F signal and controlling the power supply to the electric pump 18 from the drive circuit 31, and outputting a command signal to the switching valve 16 to execute the switching operation. The cuff pressure P is adjusted as described above. At the same time, the CPU 24 executes a series of blood pressure measurement operations, and determines the cuff pressure P at the time when the Korotkoff sound occurs and disappears as the systolic blood pressure value and the diastolic blood pressure value, respectively, based on the pulse sound signal SO and the cuff pressure signal SP. At the same time, the determined blood pressure value is displayed on the blood pressure display 29. The blood pressure display 29 has a horizontal axis 21 and a vertical axis 23 representing time and blood pressure (tm), respectively, as shown in FIG.
A bar graph 25 whose upper end A and lower end B represent the systolic blood pressure value and the diastolic blood pressure value, respectively, is successively and continuously displayed on a cathode ray tube provided with a two-dimensional chart representing l(g).

Further, a pulse wave sensor 32 is connected to the CPU 24 via an A/D converter 34. The pulse wave sensor 32 is the fourth
As shown in the figure, it is attached to a band 36 that has a pair of fasteners (not shown) at both ends, and is placed on the radius bone near the wrist of the living body, where it is easy to collect pulse waves. 36 is wrapped around the wrist of a living person and the fasteners are brought into close contact with each other, so that the radial artery located on the radial bone is locally pressed with a constant pressure of about 10 to 100 mm) Ig. ing.

That is, the pulse wave sensor 32 detects a pulse wave from the radial artery and supplies a pulse wave signal SM representing the pulse wave to the CPU 24 via the A/D converter 34. As the pulse wave sensor 32, a semiconductor strain sensor, a piezoelectric element, or the like is used to convert the pulsation of the artery into an electrical signal. Note that the pulse wave sensor 32 is
The cuff 10 is attached to the wrist of the arm opposite to the arm around which it is wrapped. The CPU 24 also has a clock signal source 3.
A pulse signal GK of a predetermined frequency is supplied from 8.

The operation of this embodiment will be explained below according to the flowchart shown in FIG.

First, when a power switch (not shown) is turned on, step S1 is executed, and it is determined whether a start/stop button (not shown) has been pressed, that is, whether a start/stop signal is being supplied to the CPU 24. When the activation stop signal is output after the cuff 10 is wrapped around the upper arm of the living body, step S2 is executed, and the count content T of the timer is reset to zero, after which the clock signal is supplied again from the clock signal source 38. starts counting the pulse signals CK. Subsequently, step S3 is executed, and the switching valve 1 is switched to the pressure supply state.
6 is switched and pressurized fluid is supplied from the electric pump 18 to the cuff 10. As a result, the cuff pressure P increases, and in step S4, the cuff pressure P becomes the predetermined target cuff pressure P.

It is determined whether or not it has been reached. This target cuff pressure P1 is set at a pressure higher than the predicted systolic blood pressure value of the living body, for example, about 180 m)Ig, and when the cuff pressure P reaches the target cuff pressure P1, step S5 is subsequently executed. Ru. In step S5, the electric pump 18 is stopped, the switching valve 16 is switched to the rate-limiting exhaust state, and the cuff pressure P is gradually lowered. and,
In such a state, step S6 is executed, and it is determined whether or not a pulse wave has been detected by the pulse wave sensor 32. If it is determined that a pulse wave has not been detected yet, the pulse wave is put on standby until it is detected. If it is determined that a pulse wave has been detected, a series of detected pulse waves are sequentially stored in the RAM 28 in step S7.

Subsequently, step S corresponding to the blood pressure measuring means of this embodiment
8 is executed, and the actual systolic blood pressure value H (mHg) and diastolic blood pressure are determined from the cuff pressure signal SP based on the occurrence and extinction of the Korotkoff sound represented by the pulse sound signal SO during the rate-limiting blood pressure lowering period of the cuff 10. Value L (wag)
are determined, and their actual blood pressure values H and L
is stored in the RAM 28. Next, step S9 is executed to determine whether the systolic and diastolic blood pressure values have been determined, and when the systolic and diastolic blood pressure values are determined, step SIO is immediately executed to switch the switching valve 16 into the rapid exhaust mode. The state is changed and the inside of the cuff 10 is rapidly evacuated, but if the determination is negative, steps 36 and subsequent steps are executed again.

In the following step 31), the pulse waves MW and ML at the time when the blood pressure values H and L were determined in step S8 are read from among the series of pulse waves stored up to that point in the RAM 28, and the pulse waves MW and ML are read. Highest values M1, 8 and M
The minimum values M * i a of L are determined, and the maximum values M, y, and minimum values M a i f
A relational expression for determining the systolic blood pressure value SYS and the diastolic blood pressure value DIA, respectively, based on i is determined as a constant and a in the % expression %(). That is, the constants and a are calculated by substituting the actual blood pressure values H and L determined in step S8 into the systolic blood pressure value SYS and the diastolic blood pressure value DIA. Here, these equations (1) and (2) are calculated based on the maximum and diastolic blood pressure values determined based on the occurrence and disappearance of Korotkoff sounds, the maximum value of the pulse wave at the time of Korotkoff sounds, and the Korotkoff sounds. This is established based on the fact that a proportional relationship is established between the lowest value of the pulse wave when the sound disappears. Therefore, the constants and a represent the slope and the intercept of the Y-axis, respectively, when the Y-axis is the blood pressure value and the X-axis is the magnitude of the pulse wave. Note that by adding the Y-intercept a, the blood pressure value does not necessarily become zero even when the magnitude of the pulse wave is zero, so the relationship between the blood pressure value and the pulse wave becomes accurate.

Next, in step S12, it is subsequently determined whether or not a pulse wave has been detected. If it is determined that a pulse wave has been detected, the subsequent step S13 is executed, and the detected pulse wave M1 is read. The maximum value m of the pulse wave M,
, 1x and the minimum (i!Em-i, , are determined. Then, in step S14, the step Sll
Since K and a have already been determined in , these maximum values m, ll! By substituting the minimum values m and i into the old formulas (1) and (2), the systolic blood pressure value SYS and the diastolic blood pressure value DIA are estimated, and in step S15, the systolic blood pressure value SYS and the diastolic blood pressure value DIA is displayed on the blood pressure display 29. Therefore, in this embodiment, step S14 corresponds to blood pressure value determining means.

In step S16, it is determined whether the start/stop push button has been operated again. If it is determined that the re-operation has been performed, the process returns to step S1, but if it is determined that the re-operation has not been performed, step S17 is executed and the count content T of the timer is changed to the predetermined count content T0. It is determined whether or not it has been reached. This counting content T0 corresponds to the time interval at which K and a are determined again in order to correct the correspondence determined in step S1), and is set to, for example, about 5 to 10 minutes.

Therefore, when the count content T reaches To, steps 82 and subsequent steps are executed again, but since the count content T has not yet reached To at this stage, steps 312 and below are executed, and Ml. The following series of pulse waves M...
M3. Each time ... is detected, the systolic blood pressure value SY
S and the diastolic blood pressure value DIA are estimated and displayed continuously.

As described above, in the process of repeating the operations from step 312 onwards, when it is determined in step S17 that the count content T of the timer has reached To, steps from 82 onwards are executed again, and a new The determined actual systolic blood pressure value H and diastolic blood pressure value,
Step Sl
, the constants and a of the correspondence equations (1) and (2) are determined again, and based on the maximum and minimum values of the pulse waves subsequently detected from the new correspondence relations (1) and (2), Blood pressure measurements are continuously performed and the measured blood pressure values are displayed. Therefore, in this embodiment, step Sll corresponds to the correction means.

As described above, in this embodiment, the actual systolic blood pressure value and diastolic blood pressure value measured at regular time intervals, and the actual blood pressure value detected by the pulse wave sensor 32 at the time when the actual blood pressure value is measured. Based on the correspondence between the highest and lowest pulse wave values, the blood pressure value is continuously measured and displayed based on the magnitude of the pulse wave. Therefore, according to this embodiment, the blood pressure value can be monitored simply by compressing a part of the living body at regular time intervals, which is different from the conventional method of continuously compressing a part of the living body at a relatively high pressure. Compared to the device described above, even when blood pressure is measured continuously over a long period of time, pain caused to the living body such as discomfort and congestion can be significantly reduced. Furthermore, according to this embodiment, the correspondence between the blood pressure value and the pulse wave is corrected each time the actual blood pressure value is detected, based on the pulse wave detected when the blood pressure value is determined. The correspondence between values and pulse waves can always be accurately obtained, and blood pressure measurement can be performed with sufficient accuracy.

Furthermore, according to this embodiment, the systolic blood pressure value and the diastolic blood pressure value of the living body can be measured simultaneously and continuously for each pulse of the artery.
It has the advantage of being able to obtain highly dense medical information. In addition, in this embodiment, it is of course possible to configure so that only either the systolic blood pressure value or the diastolic blood pressure value is continuously measured, and it is also possible to configure so that the average blood pressure value etc. are continuously measured. .

In addition, in this example, since the positional method is adopted as the blood pressure measurement method, the systolic and diastolic blood pressure values are determined almost simultaneously with the generation and disappearance of Korotkoff sounds.
This method has the advantage that the correspondence between the magnitude of the pulse wave and the blood pressure value can be easily and quickly obtained. Note that, in place of the pre-K method, other methods, such as an oscillometric method that determines the blood pressure value based on changes in the magnitude of the pulse wave of the living body, may be used to obtain sufficient effects.

Next, another embodiment of the present invention will be described. Note that in the following embodiments, parts common to those in the above-described embodiments are designated by the same reference numerals, and explanations thereof will be omitted.

As shown in FIG. 6, a state in which the correspondence relationship between the brachial blood pressure value determined in step Sll and the pulse wave is considered to have deviated, such as body movement of the pulse wave detection unit near the wrist or a change in peripheral blood flow resistance. If the above is determined from the pulse wave, step 318 may be provided to recalculate the relationship. This is because when peripheral blood flow resistance changes due to contraction or expansion of peripheral blood vessels, the correspondence between the brachial blood pressure value and the blood pressure value determined based on the pulse wave of the radial artery shifts. The step 318 is provided, for example, between steps S13 and 314 in FIG. 5, and determines whether the radial pulse wave is abnormal. In this step 318, for example,
Regarding the body movement of the pulse wave detection unit, the amplitude of the radial pulse wave, the baseline (
For example, when the magnitude from the zero volt line to the peak value of the radial pulse wave changes by 50% or more within a unit time (for example, 5 seconds), it is determined to be abnormal. Alternatively, an abnormality is determined when the generation timing of the radial pulse wave deviates, for example, by 30% or more from the normal generation cycle. Regarding the change in peripheral blood flow resistance, as shown in Figure 7, the value indicating the position of the notch (for example, the size A from the notch to the upper peak value) with respect to the radial pulse wave. /When the size B) from the notch to the lower peak value changes by 30% or more within a unit time, it is determined to be abnormal. Alternatively, an abnormality is determined when the rate of change (slope) of a portion of the radial pulse wave corresponding to the diastole phase (falling portion C after the notch) changes significantly. Alternatively, the blood pressure value based on the radial pulse wave when the relationship between the magnitude of the radial pulse wave and the brachial blood pressure values H and L is determined in step Sll, and the blood pressure value based on the subsequent radial pulse wave. When the difference changes by, for example, 40 mHg or more, it is determined to be abnormal.

Although one embodiment of the present invention has been described above based on the drawings,
The present invention can also be suitably implemented in other embodiments.

In the above example, pulse waves were collected from the radial artery near the wrist of the living body, but other blood vessels where pulse waves can be easily collected because they are located relatively close to the living body's surface, such as the carotid artery 9 pedis dorsalis. Pulse waves may also be detected from arteries or finger blood vessels.

Further, in the above embodiment, the pulse wave sensor 32 is fixed on the radial artery near the wrist by the band 36 and is pressed against the radial artery with a constant pressing force. It may be arranged as shown in FIG. That is, a small cuff 40 having substantially the same structure as the cuff 10 is wound around the finger of the hand on the opposite side of the blood pressure measurement side, and the cuff 4
The cuff 40 is supplied with pressure fluid from the electric pump 42 into the cuff 40.
The pressure inside the cuff 40 may be increased to a predetermined pressure, and pressure vibrations generated within the cuff 40 in synchronization with the pulse of the living body may be detected by a pressure sensor 46 connected to the cuff 40 through an air pipe 44. At this time, a pressure regulating valve 48 controlled by the CPU 24 is attached to the air piping 44, and the magnitude of the pulse wave signal output from the pressure sensor 46 to the CPU 24 in response to pressure vibrations within the cuff 40. For example, the amplitude, signal power, etc. are calculated by the CPU 24, and it is detected whether the magnitude is saturated or not, and when the magnitude is saturated, the pressure regulating valve 48 is activated so that the pressure in the cuff 40 at that time is maintained. It is designed to be feedback controlled. Note that instead of changing the cuff pressure so that the magnitude of the pulse wave signal is saturated, it is also possible to control the inside of the cuff 40 to maintain a predetermined suitable pressure.

In addition, instead of the band 36, a fluid container that accommodates the pulse wave sensor 32, and a diaphragm such as rubber that fixes the pulse wave sensor 32 so as to come into contact with the biological surface within the fluid container and seals the inside of the fluid container. The fluid container and diaphragm are fixed directly above the blood vessel on the surface of the living body, and when pressure fluid whose pressure is regulated by a pressure regulating valve or the like is supplied into the fluid container, the pulse wave sensor 32 is activated by the action of the diaphragm. It is also possible to detect the pulse wave by pressing with a suitable pressing force. Also,
By providing the pulse wave sensor 32 inside the fluid container, on the fluid container, or outside the fluid container, and by blocking the contact surface of the fluid container with the living body with the diaphragm, the pulse wave sensor 32 is connected to the fluid in the fluid container and through the diaphragm. A pressure vibration wave corresponding to the wave may be detected by a pulse wave sensor.

For example, by fixing electrodes at two positions separated by a predetermined distance on a part of a living body such as a finger and passing a weak current through the finger, a vibration wave corresponding to a pulse wave can be generated from the impedance generated between the two electrodes. It may also be detected. Further, a light projector and a light receiver are provided above and below a relatively thin part such as a finger, and the light receiver receives the light projected so as to pass through the blood vessels located in that part,
Blood vessel pulsation can also be detected from changes in the wavelength of the received light. Note that even in the above-described method, when a pulse wave is detected from an arm or hand, the pulse wave sensor is provided on the arm or hand on the opposite side to the side on which the blood pressure value is measured.

In addition, in the above-mentioned example, the correspondence relationship between the actual blood pressure value and the pulse wave size is calculated on the premise that they are in a proportional relationship, but the blood pressure value is a quadratic function of the pulse wave size. The blood pressure value and pulse wave size of the living body being measured can be determined from among multiple types of data maps that express the correspondence relationship between the blood pressure value and the pulse wave size that has been programmed in advance. There is no problem in finding the correspondence in other ways, such as finding the correspondence by selecting one data map based on the data map.

In addition, in the above embodiment, the slope K and the Y-intercept a were used in the correspondence between the blood pressure value and the pulse wave size, but even if only the slope K is used, the accuracy of blood pressure measurement is sufficient. It can be obtained. In this case, the systolic blood pressure value SYS, the highest pulse wave value, and the diastolic blood pressure value DIA
Two types of slopes K may be obtained by assuming that the proportional relationship between the minimum value of the pulse wave and the minimum value of the pulse wave is different.

Furthermore, in the above embodiment, in the blood pressure measuring means, the blood pressure value was determined during the blood pressure lowering process of the cuff 1o based on the generation and extinction of the Korotkoff sounds collected by the microphone 12, but in the blood pressure increasing process of the cuff 10, It is also possible to perform blood pressure measurements.

Further, in the above embodiment, the continuously measured systolic and diastolic blood pressure values are displayed on the cathode ray tube, but they may also be printed and recorded on recording paper such as a chart at the same time. Various other display means or storage means may be employed.

The above-mentioned embodiment is merely one embodiment of the present invention, and various modifications may be made to the present invention without departing from the spirit thereof.

[Brief explanation of the drawing]

FIG. 1 is a diagram corresponding to claims of the present invention. FIG. 2 is a diagram illustrating the configuration of a blood pressure monitoring device that is an embodiment of the present invention. FIG. 3 is a diagram showing an example of the trend of blood pressure values displayed on the blood pressure display device in FIG. 2. FIG. 4 is a diagram showing a state in which the pulse wave sensor shown in FIG. 1 is attached to the wrist of a living body. FIG. 5 is a flowchart illustrating the operation of the apparatus of FIG. FIG. 6 is a flowchart illustrating the main part of the operation of another embodiment of the present invention. FIG. 7 is a diagram illustrating the notch position of the pulse wave or the portion corresponding to the diastole phase of the heart. FIG. 8 is a diagram illustrating the configuration of a pulse wave sensor employed in another embodiment of the present invention. 10: Cuff 32: Pulse wave sensor 46: Pressure sensor Step S8: Blood pressure measuring means Step S1): Correction means Step S14: Blood pressure value determining means Applicant: Korin Electronics Co., Ltd. Figure 1 Figure 3 Figure 4/ Figure 5 Figure 6 Figure 7

Claims (2)

[Claims] (1) A blood pressure monitoring method that monitors the blood pressure value of a living body based on a pulse wave detected by a pulse wave sensor based on a predetermined relationship, the method comprising a cuff for compressing a part of the living body; a blood pressure measurement step of measuring the blood pressure value of the living body by compression of the cuff; and a blood pressure value determined in the blood pressure measurement step, and the pulse wave sensor when the cuff is compressing at the same pressure as the blood pressure value. A blood pressure monitoring method comprising: a correction step in which the relationship is corrected based on the pulse wave detected by the blood pressure monitoring method. (2) A blood pressure value determining means for determining the blood pressure value of the living body based on the pulse wave detected by the pulse wave sensor from a predetermined relationship, and the blood pressure of the living body is determined based on the blood pressure value determined by the blood pressure value determining means. A blood pressure monitoring device for monitoring a blood pressure value, comprising: a blood pressure measuring means having a cuff for compressing a part of a living body, and measuring a blood pressure value of the living body by compressing the cuff; and a blood pressure value determined by the blood pressure measuring means. and a correction means for correcting the relationship based on the blood pressure value determined by the blood pressure value and the pulse wave detected by the pulse wave sensor when the cuff is compressing at the same pressure as the blood pressure value. blood pressure monitoring device.