JP3147256B2 - Non-invasive blood pressure measurement device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-invasive blood pressure measuring device .
For example, the present invention relates to a non-invasive blood pressure measurement device that indirectly measures blood pressure by pressing a part of a living body with a cuff and measuring the cuff pressure.

[0002]

2. Description of the Related Art Generally, there are an invasive type (direct type) and a non-invasive type (indirect type) as a blood pressure measuring method, and the latter non-invasive type is compared with the former invasive type. It is well known that measurement methods are widely used because they are simple and the like. This non-invasive blood pressure measurement method is further roughly classified into the following two types depending on whether the blood pressure measurement is performed during depressurization of the cuff or during pressurization. One is the most common method, in which the cuff is pre-pressurized to a pressure sufficiently higher than the subject's systolic blood pressure, and then slowly decompressed, and measurement is performed during the decompression. is there. Another method is to slowly pressurize the cuff and measure during the pressurization.

[0003]

[Problems to be solved by the invention]

(1) Among the above-mentioned prior arts, the first problem of the method of measuring during decompression is that the reproducibility of the measurement result may be low. That is, in the method of measuring during decompression, almost the same measurement result is always obtained as long as the decompression speed of the cuff is constant.
However, this decompression speed varies depending on the size of the cuff, the thickness of the arm of the subject to which the cuff is wound, the manner in which the cuff is wound, and the like, and is not always constant. For this reason, the measurement accuracy depends on the decompression speed, and the reproducibility of the measurement result is low. A second problem of the method of measuring during decompression is to give unnecessary pain to the subject. That is,
As described above, in the method of measuring during decompression, the cuff must be pressurized to a pressure sufficiently higher than the systolic blood pressure value of the subject in advance. However, if the systolic blood pressure value is not known, the cuff is often pressurized more than necessary. As a result, unnecessary pain is given to the subject whose pressure cuff is wound around the arm. (2) Further, of the above-mentioned conventional techniques, the problem of the method of measuring during pressurization is that the measurement result may be largely shifted as compared with the method of measuring during depressurization. That is, in the method of measuring during pressurization, the arm of the subject is tightened with a cuff, whereas in the method of measuring during decompression, the arm of the subject is loosened. However, the condition is not the same between the case where the arm is tightened with the cuff and the case where the arm is loosened, due to the blood vessel tissue etc. of the subject. Etc. will be different. For this reason, a large deviation may occur in the measurement result. An object of the present invention is to provide a non-invasive blood pressure measurement method and a device therefor that have high reproducibility of a measurement result, have little deviation, and do not cause unnecessary pain to a subject.

[0004]

Means for Solving the Problems The present invention solves the above problems.
It was made for the purpose of
For example, a cuff 1 that presses a part of a living body to achieve
And the cuff pressure of the cuff 1 at a predetermined speed at which blood pressure can be measured.
Pressurizing means 2 for feeding air to the cuff 1 so as to rise;
The cuff pressure of the cuff 1 is reduced at substantially the same speed as the rising speed.
A pressure reducing means 3 for exhausting from the cuff 1 so as to descend,
A signal corresponding to the cuff pressure of the cuff is input, and
Control with the step and the pressure reducing means and at a predetermined time.
The cuff pressure is measured to determine the blood pressure during pressurization and decompression,
A systolic blood pressure value and a diastolic blood pressure value based on the blood pressure determination result.
A blood pressure determination calculating means 4 for calculating the blood pressure.
The dispensing means 4 adjusts the cuff pressure of the cuff 1 by the pressurizing means.
Raises pressure by measuring the cuff pressure at a given time point do blood pressure determination of pressurized, before the cuff pressure by the pressure reducing means
By vacuum at approximately the same speed as by pressurizing speed KiKa圧means, by measuring the cuff pressure at a given time point do blood pressure determination at the time of decompression, prior Symbol pressurization of the blood pressure determination result blood pressure during decompression The systolic blood pressure value and the diastolic blood pressure value are calculated based on the average value of the determination results. Or, one of the living
The cuff 1 for compressing the part and the cuff pressure of the cuff 1 are used for measuring blood pressure.
Inflate the cuff 1 so that it rises at the prescribed speed possible
Pressurizing means 2 and the cuff pressure of the cuff 1 increase at the above-mentioned rising speed.
Exhaust from the cuff 1 so that it descends at almost the same speed as
And a signal corresponding to the cuff pressure of the cuff.
Input and control with the pressurizing means and the depressurizing means.
Measure the cuff pressure at a given point in time to increase and decrease pressure
Blood pressure determination, and based on the blood pressure determination result, the systolic blood pressure
Blood pressure determination calculating means 4 for calculating the blood pressure value and the diastolic blood pressure value.
The blood pressure determination calculation means 4 is operated by the pressure means.
The cuff pressure of the cuff 1 is increased by increasing the cuff pressure.
The cuff pressure is measured to determine the blood pressure during pressurization,
The cuff pressure is almost the same as the pressurizing speed by the pressurizing means.
By reducing the pressure at the same speed, the
The pressure is measured to determine the blood pressure at the time of pressure reduction,
Correction of average value of blood pressure judgment result and blood pressure judgment result at decompression
Calculate the systolic and diastolic blood pressure values based on these values.
Sign. Then, for example, the blood pressure determination calculating means 4
At a predetermined point in time when the cuff pressure is measured, a Korotkoff sound is generated.
At the time of disappearance and at the time of disappearance. is there
Alternatively, the predetermined time for measuring the cuff pressure is the cuff pressure
When the first inflection point of the wave trend curve is detected and
It is characterized by the point at which two inflection points are detected. Ma
For example, when performing blood pressure determination repeatedly,
Performs the blood pressure determination at the time of the pressurization and the pressure reduction, and
After the first time, only the blood pressure determination at the time of pressurization is performed.
And Alternatively, the pressurizing means 2 controls the flow rate for pressurization.
Including a valve 2A, an air supply pump 2B, and a driving unit 9;
Features. Further, for example, the decompression means 3 is used for decompression.
It is characterized by including a flow control valve 3A and a drive unit 9.
You. Alternatively, the blood pressure determination calculating means 4
It is characterized by including. Further, for example, the blood pressure determination calculation
A cuff for measuring the pressure in the cuff is provided on the input side of the output means 4.
Korotkoff sound recognizing Korotkoff sound with pressure conversion means 14
It is characterized in that the recognition means 15 is connected. is there
Alternatively, the cuff pressure converting means 14 includes a pressure sensor 14A.
And a pressure amplifier 14B and an AD converter 14C.
It is characterized by. Alternatively, the Korotkoff sound recognition means 15
Is a Korotkoff sound sensor 15A and a Korotkoff sound amplifier.
15B, a bandpass filter 15C, and a comparator 15D.
It is characterized by the following. For example, the blood pressure determination calculating means 4
At the input side of the cuff, the pressure inside the cuff is measured and the cuff pressure is measured.
Cuff pressure conversion for extracting oscillating artery waves and extraction of cuff pressure oscillating artery waves
It is characterized in that the means 16 is connected. There
Is the cuff pressure conversion and cuff pressure oscillation arterial wave extraction means 16
Is a pressure sensor 16A, a pressure amplifier 16B, AD conversion
And a pressure pulse wave amplifier 16D.
I do .

[0005]

According to the above arrangement, the blood pressure is determined both during pressurization and depressurization, and the average value or the correction value of the average value is used as the measurement result. Since the influence on accuracy can be reduced (FIG. 5 (A),
(FIG. 5B), the reproducibility of the measurement result is high, and a non-invasive blood pressure measurement device with little deviation can be obtained . In addition, the systolic blood pressure value is determined when the cuff pressure increases and decreases (see FIG. 5).
(A), FIG. 5 (B)), the cuff is no longer pressurized more than necessary, and unnecessary pain is not given to the subject. That is, measurement is high reproducibility result, deviation is less, and non-invasive blood pressure measurement apparatus which does not give an unnecessary pain to the subject can be provided.

[0006]

EXAMPLES Hereinafter, will be explained with reference to the accompanying drawings an embodiment of the present invention. 1. 1st invention The 1st invention raises the cuff pressure at a constant speed at which the blood pressure can be measured, thereby measuring the cuff pressure at a predetermined point in time and determining the blood pressure at the time of pressurization. By descending at substantially the same speed, the cuff pressure at a predetermined time is measured to determine the blood pressure at the time of pressure reduction, and the systolic blood pressure value and the diastolic blood pressure value are calculated based on the blood pressure determination results at the time of pressure increase and pressure reduction. This is a non-invasive blood pressure measurement method.

1-A First Embodiment Hereinafter, a first embodiment will be described in detail with reference to FIG. 1 and FIG. In FIG. 5 (A), the upper diagram depicts a cuff pressure curve C representing a change in cuff pressure with the vertical axis representing the cuff pressure P and the horizontal axis representing time t. This represents a change in the Korotkoff sound K which is a signal. (1) First, by increasing the cuff pressure at a predetermined speed at which blood pressure can be measured, the cuff pressure at a predetermined time is measured to determine the blood pressure at the time of pressurization. First step Q1 in FIG.
, The high-speed pressurization of the cuff pressure P is started, and is continued in the second step Q2 until it is determined whether or not the initial pressurization value P1 has been exceeded (the portion of the straight line C11 shown in FIG. 5A). Since the initial pressure value P1 detects a diastolic blood pressure value, the pressure is appropriately lower than the diastolic blood pressure value, for example, 30 mm.
Hg is set. When the cuff pressure P becomes equal to or more than the initial pressurization value P1, in a third step Q3, the cuff pressure P is pressurized at a low speed, and as shown by a pressurization straight line C1 in FIG.
The cuff pressure is increased at a constant rate at which blood pressure can be measured (for example, 3 mmHg / sec). Next, in the fourth step Q4, the Korotkoff sound K is detected, and in the fifth step Q5, it is determined whether or not the blood pressure determination has been completed. The detection of the Korotkoff sound K in the fourth step Q4 is continued. The third step Q3, the fourth step Q4, and the fifth step
Through a series of operations consisting of step Q5, the cuff pressure at a predetermined time is measured to determine the blood pressure at the time of pressurization. That is, in FIG. 5A, if the cuff pressure Pd1 at the time t1 at which the Korotkoff sound K is generated is measured, this Pd1 becomes the minimum blood pressure value Pd1 at the time of pressurization. In FIG. 5A, the cuff pressure Ps1 at time t2 when the Korotkoff sound K disappears.
Is measured, this Ps1 is the systolic blood pressure value Ps1 at the time of pressurization.
Becomes When the blood pressure determination is completed in this way, in the sixth step Q6, the systolic blood pressure value Ps1 and the diastolic blood pressure value Pd1 determined at the time of pressurization are stored in, for example, the RAM 22 (FIGS. 3 and 4), It is used for calculating the blood pressure value in 12 steps Q12.

(2) Next, the cuff pressure is decreased at substantially the same speed as the above-mentioned increasing speed, so that the cuff pressure at a predetermined time is measured to determine the blood pressure when the pressure is reduced. 7 of FIG.
In step Q7, the cuff pressure P is reduced at a low speed, and FIG.
As shown by the decompression straight line C2 in (A), the cuff pressure is decreased at substantially the same speed as the increasing speed at the time of pressurization (for example, 3
mmHg / sec). Next, in the eighth step Q8, the Korotkoff sound K is detected, and the ninth step Q8 is performed.
In step 9, it is determined whether the blood pressure determination has been completed. Until then, the low-speed depressurization in the seventh step Q7 and the eighth
The detection of the Korotkoff sound K in step Q8 is continued. By a series of operations including the seventh step Q7, the eighth step Q8, and the ninth step Q9, the cuff pressure at a predetermined time is measured to determine the blood pressure at the time of pressure reduction. That is, FIG.
In (A), if the cuff pressure Ps2 at the time t3 when the Korotkoff sound K is generated is measured, this Ps2 becomes the systolic blood pressure value Ps2 at the time of pressure reduction. Further, in FIG. 5A, if the cuff pressure Pd2 at the time point t4 when the Korotkoff sound K disappears is measured, this Pd2 becomes the minimum blood pressure value Pd2 at the time of pressure reduction.
When the blood pressure determination is completed in this manner, in the tenth step Q10, the systolic blood pressure value P determined at the time of decompression is determined.
s2 and the diastolic blood pressure value Pd2 are stored in, for example, the RAM 22 (FIG. 3,
4) and used for calculating a blood pressure value in a twelfth step Q12 described later. Then, the eleventh step Q
At 11, the pressure is reduced at a high speed, and the cuff pressure is released (the portion of the straight line C21 shown in FIG. 5A).

(3) Finally, a systolic blood pressure value and a diastolic blood pressure value are calculated based on the blood pressure determination results at the time of pressurization and decompression. If the systolic blood pressure value is Ps and the diastolic blood pressure value is Pd, the calculated Ps and Pd are calculated based on the following equations (1) and (2). Ps = a · Ps1 + b · Ps2 (1) Pd = c · Pd1 + d · Pd2 (2) However, in the equation (1), Ps1 is the systolic blood pressure value at the time of pressurization, and Ps2 is It is the systolic blood pressure value at the time of decompression, and (2)
In the equation, Pd1 is the diastolic blood pressure value when pressurized, and Pd2 is the diastolic blood pressure value when depressurized. Further, a, b, c, and d in the expressions (1) and (2) are constants, and the average value is set to the systolic blood pressure value Ps and the diastolic blood pressure value Pd, or the correction value of the average value is set to the systolic blood pressure value. It can be set arbitrarily depending on whether the value is the value Ps and the diastolic blood pressure value Pd. Normally, take the average, a = b = c = d
= 0.5, and when taking a correction value, for example, a =
c = 0.3 and b = d = 0.7. The calculated systolic blood pressure value Ps and diastolic blood pressure value Pd are calculated in the thirteenth step Q1.
3, the information is displayed on the display 18 (FIGS. 3 and 4), for example.

1-B Second Embodiment Hereinafter, a second embodiment will be described in detail with reference to FIGS. 2 and 5B. The difference from the first embodiment (FIGS. 1 and 5A) is that the Korotkoff sound K is used in the first embodiment as a reference signal for blood pressure determination, whereas the second embodiment is different from the first embodiment (FIGS. 1 and 5A). Is that cuff pressure arterial waves are used. This difference is specifically caused by the fourth step R4 (step corresponding to the fourth step Q4 in FIG. 1) and the fifth step R5 (the fifth step Q5 in FIG. 1) which are steps during pressurization shown in FIG.
And the eighth step which is a step at the time of pressure reduction.
Step R8 (a step corresponding to the eighth step Q8 in FIG. 1) and a ninth step R9 (a step corresponding to the ninth step Q9 in FIG. 1) respectively appear.

At the time of pressurization, the cuff pressure oscillating artery wave is detected in a fourth step R4 in FIG. 2, and it is determined in a fifth step R5 whether or not the blood pressure determination has been completed. 3 step R3 low speed pressurization,
The detection of the cuff pressure oscillation arterial wave in the fourth step R4 is continued. By a series of operations including the third step R3, the fourth step R4, and the fifth step R5, the cuff pressure at a predetermined time is measured to determine the blood pressure at the time of pressurization. That is,
In FIG. 5B, the trend curve V of the cuff pressure oscillation arterial wave is shown.
Cuff pressure Pd1 at time t5 when the first inflection point I1 is detected
Is measured, this Pd1 is the diastolic blood pressure value Pd1 at the time of pressurization.
Becomes Further, in FIG. 5B, at time t6 when the second inflection point I2 of the trend curve V of the cuff pressure-oscillating artery wave is detected.
Is measured, the cuff pressure Ps1 becomes the systolic blood pressure value Ps1 at the time of pressurization.

At the time of pressure reduction, in an eighth step R8,
The cuff pressure oscillation artery wave is detected, and it is determined in the ninth step R9 whether or not the blood pressure determination has been completed. Until then, the low-speed depressurization in the seventh step R7 and the cuff pressure oscillation in the eighth step R8 have been performed. The detection of the arterial wave is continued. The seventh step R7, the eighth step R8, and the ninth step R
9, the cuff pressure at a predetermined time is measured to determine the blood pressure at the time of pressure reduction. That is, FIG.
In (B), if the cuff pressure Ps2 at the time point t7 when the first inflection point I1 of the trend curve V of the cuff pressure-oscillating artery wave is detected, this Ps2 becomes the systolic blood pressure value Ps2 at the time of decompression. In FIG. 5B, if the cuff pressure Pd2 at time t8 when the second inflection point I2 of the trend curve V of the cuff pressure oscillating artery wave is detected, this Pd2 becomes the lowest blood pressure value Pd2 at the time of decompression. Becomes

In the second embodiment (FIG. 2), the first
Step R1, second step R2, third step R3,
Sixth step R6, seventh step R7, tenth step R10, eleventh step R11, twelfth step R12
And the thirteenth step R13 are the first step Q1, the second step Q2, and the third step Q of the first embodiment (FIG. 1).
3, sixth step Q6, seventh step Q7, tenth step Q10, eleventh step Q11, twelfth step Q
Since it is the same as the twelfth and thirteenth steps Q13, description thereof will be omitted.

In the first embodiment (FIG. 1) and the second embodiment (FIG. 2), when the blood pressure determination is repeatedly performed, the blood pressure determination at the time of pressurization and the pressure reduction at the first time is performed. From the second time onward, it is preferable to perform only the blood pressure determination during pressurization. This situation is shown in FIG. 5 (C), which has the effect that the non-invasive blood pressure measurement can be performed quickly during the operation. If the blood pressure is repeatedly determined n times from the second time onward, if the blood pressure determination results only during pressurization at the nth time are Ps1 (n) and Pd1 (n) (FIG. 5 (C)),
Corrected systolic blood pressure value Ps (n) and diastolic blood pressure value Pd
(N) is calculated by the following equations (3) and (4). Ps (n) = (a + b · Ps2 / Ps1) Ps1 (n) (3) Pd (n) = (c + d · Pd2 / Pd1) Pd1 (n) (4) Equation (3) , Ps1 is the systolic blood pressure value at the first pressurization at the first pressurization, Ps2 is the systolic blood pressure value at the first pressurization at the time of decompression, and in the equation (4), Pd1 is the pressurization at the first pressurization. The diastolic blood pressure value at the time, Pd2, is the diastolic blood pressure value at the first time of decompression (FIGS. 1, 2, 5A, and 5B). That is, from the above equation (1), the systolic blood pressure value Ps (n) is calculated as follows: Ps (n) = a · Ps1 (n) + b · Ps2 (n) (5) Is proportional to the value measured at the n-th measurement. Ps2 (n) = Ps2 · Ps1 (n) / Ps1 (6) From the equations (5) and (6), If Ps2 (n) is deleted,
The above equation (3) is obtained. Similarly, the diastolic blood pressure value Pd
Also for (n), the above equation (4) is obtained by deriving from the above equation (2).

2. Second invention A second invention is to input a cuff 1 for compressing a part of a living body and a signal corresponding to the cuff pressure, and send the signal to the cuff 1 so that the cuff pressure rises at a constant speed at which blood pressure can be measured. Pressure means 2 for inputting a signal corresponding to the cuff pressure, and pressure reducing means 3 for exhausting from the cuff 1 such that the cuff pressure decreases at substantially the same speed as the above-mentioned rising speed, and a pressure corresponding to the cuff pressure. A blood pressure determination calculating means 4 for inputting a signal, measuring cuff pressure at a predetermined time point, performing blood pressure determination during pressurization and pressure reduction, and calculating a systolic blood pressure value and a diastolic blood pressure value based on the blood pressure determination result. A non-invasive blood pressure measurement device characterized by comprising:

2-A First Embodiment of the Second Invention The first embodiment of the second invention will be described below in detail with reference to FIG. 3, reference numeral 1 denotes a cuff, 2 denotes a pressurizing unit, 3 denotes a depressurizing unit, 4 denotes a blood pressure determination calculating unit, and 6 denotes an RO.
M and 7 are RAMs, and 8 is a display. The cuff 1 is a band that presses a part of the living body, for example, the upper arm of the subject by air pressure, as is well known.

The pressurizing means 2 inputs a signal corresponding to the cuff pressure, and applies a signal corresponding to the cuff pressure to the cuff 1 so that the cuff pressure increases at a constant speed at which blood pressure can be measured (a straight line C1 in FIG. 5A). An air supply device, for example, as shown, a pressurizing flow control valve 2A, an air supply pump 2B, a driving unit 9, a CP
U10. The pressurizing flow control valve 2
A is a valve that controls the flow rate when the air A1 is fed into the cuff 1 via the air tube 11, and is controlled by the control signal S2a from the drive unit 9 in the case of high-speed pressurization (FIG.
(A) Straight line C11) Control to maximize the air supply flow rate. In the case of low-pressure application (Line C1 in FIG. 5A), supply air at a speed appropriate for blood pressure measurement and at a constant speed. Control the flow rate. The air supply pump 2B is a pump that supplies the air A2 to the pressurizing flow control valve 2A via the air tube 12, and is controlled by a control signal S2b from the driving unit 9.
Operate. The drive unit 9 receives the control signal S23 from the CPU 10, amplifies the current, outputs the control signals S2a and S2b, and as described above, the pressurizing flow control valve 2A and the air supply pump. 2B is driven. The above CPU
10 receives the signal S14c corresponding to the cuff pressure and outputs the control signal S23 while constantly monitoring the pressurized state of the cuff 1 (the straight lines C11 and C1 in the upper diagram of FIG. 5A), and outputs the control signal S23.
Control. The CPU 10 is not only a component of the pressurizing means 2 but also a component of other means described in detail below. Further, the CPU 10 controls and calculates the entire non-invasive blood pressure measuring device according to the present invention. And is connected via a data bus 13 to a ROM 6, a RAM 7, a display 8 and the like, which will be described later.

The pressure reducing means 3 receives a signal corresponding to the cuff pressure and exhausts the gas from the cuff 1 so that the cuff pressure decreases at a speed substantially equal to the rising speed (a straight line C2 in FIG. 5A). The apparatus includes, for example, a pressure reducing flow control valve 3A, a driving unit 9, and a CPU 10 as shown in the figure. The depressurizing flow control valve 3A is a valve that controls the flow rate when the air A3 is discharged from the cuff 1 via the air tube 11, and is controlled by a control signal S3a from the driving unit 9 to perform high-speed depressurizing. (Line C in FIG. 5A)
21) Exhaust flow rate is controlled to be the maximum, and in the case of low-speed depressurization (straight line C2 in FIG. 5A), the exhaust flow rate is controlled at a speed appropriate for blood pressure measurement and at a constant speed. The drive unit 9 receives the control signal S23 from the CPU 10, amplifies the current, outputs the control signal S3a, and drives the pressure reducing flow control valve 3A as described above. The CPU 10 generates a signal S14c corresponding to the cuff pressure.
While monitoring the decompression state of the cuff 1 (see FIG. 5).
(A) Straight lines C2 and C21 in the upper figure) and a control signal S23 are output to control the driving unit 9.

The blood pressure determination calculating means 4 inputs a signal corresponding to the cuff pressure, measures the cuff pressure at a predetermined point in time, makes a blood pressure determination at the time of pressurization and a pressure reduction, and based on the blood pressure determination result. This is a device for calculating a systolic blood pressure value and a diastolic blood pressure value, and is constituted by, for example, a CPU 10 as shown in the figure.

In the first embodiment according to the second invention , a cuff pressure converting means 14 and a Korotkoff sound recognizing means 15 are connected to the input side of the blood pressure determination calculating means 4 as shown in the figure. The cuff pressure converting means 14 is a device for converting a cuff pressure into an electric signal, and includes a pressure sensor 14A, a pressure amplifier 14B, and an AD converter 14C. The pressure sensor 14A is connected to the cuff 1 by the air tube 11, and converts the cuff pressure into an electric signal S14a. The pressure amplifier 14B amplifies the signal S14a from the pressure sensor 14A, and amplifies the amplified pressure signal S14.
b is output. The AD converter 14C is a pressure amplifier 1
An analog pressure signal S14b from 4B is input, converted into a digital signal, and a digital pressure signal S14c is output.

The Korotkoff sound recognizing means 15 comprises:
A device for inputting a vibration sound from a blood vessel of a subject and recognizing Korotkoff sound, comprising: a Korotkoff sound sensor 15A;
A Korotkoff sound amplifier 15B, a bandpass filter 15C,
And a comparator 15D. The Korotkoff sound sensor 15A is provided in the cuff 1 and receives a vibration sound from a blood vessel of the subject and converts it into an electric signal S15a. The Korotkoff sound amplifier 4F amplifies the signal S15a from the Korotkoff sound sensor 15A and outputs an amplified signal S15b. The bandpass filter 15C receives the amplified signal S15b and outputs a signal S15c from which noise components have been removed. The comparator 15D outputs the signal S1
5c, and compares it with the threshold value Th. If it is equal to or greater than the threshold value Th, it is recognized as Korotkoff sound K (FIG.
((A) lower figure), and outputs a recognition signal S15d.

By means of the cuff pressure converting means 14 and the Korotkoff sound recognizing means 15, the CPU 10 as the blood pressure determination calculating means 4 can use the AD converter 14 which is a cuff pressure corresponding signal.
The digital pressure signal S14c from C and the Korotkoff sound recognition signal S15d from the comparator 15D to detect a predetermined point in time as a reference for blood pressure determination are input. As a result, as shown in FIG. 5A, the CPU 10 determines the time points t1 and t3 at which the Korotkoff sound K has occurred and the time points t2 and t2
The cuff pressure P at t4 is measured to determine the blood pressure at the time of pressurization (C1) and at the time of depressurization (C2) (Ps1, Pd1, Ps).
2, Pd2), the systolic blood pressure value and the diastolic blood pressure value are calculated based on the blood pressure determination result.

The ROM 6 stores a program for activating the CPU 10, the RAM 7 stores a blood pressure determination result and the like, and the display 8 displays data such as a systolic blood pressure value and a diastolic blood pressure value calculated by the CPU 10.

The operation of the first embodiment according to the second invention having the above configuration will be described below with reference to FIGS. 3 and 5A. (1) Operation at the time of pressurization First, the cuff pressure is converted into the electric signal S1 by the pressure sensor 14A which constitutes the cuff pressure converting means 14 and is coupled to the cuff 1.
4a and input to the pressure amplifier 14B.
The digital pressure signal S14c is digitally converted by the converter 14C and input to the CPU 10. Thereby, C
The PU 10 controls the cuff pressure so that a high-speed pressurizing straight line C11 up to the initial pressurizing value P1 and a low-speed pressurizing straight line C1 after P1 are obtained as shown in the upper diagram of FIG. That is, the CPU 10 constituting the pressurizing unit 2 sends the control signal S23 to the drive unit 9 while reading the cuff pressure P. The control signal S
23, the driving unit 9 of the pressurizing unit 2 receives the control signal S2
b to the air supply pump 2B and the control signal S2a to the pressurizing flow control valve 2A. Thereby, the air supply pump 2
B sends the air A2 to the pressurizing flow control valve 2A through the air tube 12, and pressurizes the pressurizing flow control valve 2A.
In the case of high-speed pressurization up to the initial pressurization value P1 by feeding air A1 into the cuff 1 through the air tube 11, (the straight line C11 in FIG. 5A) In the case of low-speed pressurization after reaching the initial pressurization value P1 (straight line C1 in FIG. 5A), the air supply flow rate is controlled at a speed appropriate for blood pressure measurement and at a constant speed. I do. On the other hand, the Korotkoff sound recognizing means 15 is constituted, and the vibration sound from the blood vessel is converted into an electric signal S15a by the Korotkoff sound sensor 15A provided in the cuff 1 and inputted to the Korotkoff sound amplifier 15B, and further, the bandpass filter 15C is turned on. The signal S15c from which the noise component has been removed is compared with the threshold value Th by the comparator 15D, and the Korotkoff sound recognition signal S15d is input to the CPU 10. Accordingly, the CPU 10 constituting the blood pressure determination calculating means 4 detects the time point t1 when the Korotkoff sound K is generated and the time point t2 when the Korotkoff sound K is generated during pressurization (the straight line C1 in FIG. 5A), and at the time points t1 and t2. The cuff pressure P is measured to determine the blood pressure, and Pd1, Ps
1 is required. The obtained Pd1 and Ps1 are stored in the RAM 7 via the data bus 13 (FIG. 3).

(2) Operation at the time of pressure reduction After the cuff pressure is input to the cuff pressure conversion means 14, a digital pressure signal S14c which is a signal corresponding to the cuff pressure is output.
Until an input is made to the CPU 10 in the next stage, the operation at the time of pressurization in the above (1) is the same. Thereby, the CPU 10 controls the cuff pressure so that the low-speed decompression straight line C2 and the high-speed decompression straight line C21 shown in the upper diagram of FIG. That is, the CPU 10 constituting the pressure reducing unit 3 sends the control signal S23 to the drive unit 9 while reading the cuff pressure P. The drive unit 9 of the pressure reducing means 3 which has received the control signal S23 receives the control signal S23.
3a is sent to the pressure reducing flow control valve 3A. As a result, the pressure reducing flow control valve 3 </ b> A is
By discharging the air A3 from the cuff 1, in the case of low-speed depressurization (straight line C2 in FIG. 5A), the exhaust flow rate is controlled so as to be at a speed appropriate for blood pressure measurement and at a constant speed. (Straight line C21 in FIG. 5A) controls the exhaust flow rate to be maximum, and unnecessary air A4 is
To escape to the outside. On the other hand, Korotkoff sound recognition means 15
The operation from the input of the vibration sound from the blood vessel to the output of the Korotkoff sound recognition signal S15d to the input to the CPU 10 at the next stage is the same as the above-described operation at the time of pressurization. Thereby, the CPU 10 constituting the blood pressure determination calculating means 4
At the time of depressurization (the straight line C2 in FIG. 5A), the time point t3 at which the Korotkoff sound K is generated and the time point t4 at which the Korotkoff sound K disappears are detected, and the cuff pressure P at the times t3 and t4 is measured to determine the blood pressure, and Ps2 and Pd2 are determined. Is required. Ps2 obtained above,
Pd2 is stored in the RAM 7 via the data bus 13 (FIG. 3).

Thereafter, the blood pressure determination calculating means 4
(1) P obtained by the blood pressure judgment at the time of pressurization and (2) at the time of pressure reduction
s1, Pd1, Ps2, and Pd2 are input from the RAM 7 via the data bus 13, and for example, the equation (1) (Ps = a · Ps1) described in the first embodiment (1-A) of the first invention is applied.
+ B · Ps2) and equation (2) (Pd = c · Pd1 + d ·
According to Pd2), the systolic blood pressure value Ps and the diastolic blood pressure value Pd
Is calculated. Further, the calculated systolic blood pressure value Ps and diastolic blood pressure value Pd are displayed on the display 8 via the data bus 13.

The second embodiment according to the 2-B second invention Hereinafter, the second embodiment of the second invention, with reference to FIG. 4,
It will be described in detail. The difference from the first embodiment (FIG. 3) is that the cuff pressure conversion and cuff pressure oscillation arterial wave extraction means 16 is connected to the input side of the blood pressure determination calculation means 4. The cuff pressure conversion and cuff pressure oscillating artery wave extraction means 16 is a device that converts the cuff pressure into an electric signal and extracts oscillating artery waves from the cuff pressure. The cuff pressure conversion and cuff pressure oscillation arterial wave extraction means 16 includes a pressure sensor 16A, a pressure amplifier 16B,
It comprises a converter 16C and a pressure pulse wave amplifier 16D. The pressure sensor 16A is connected to the cuff 1 by the air tube 11, and converts the cuff pressure into an electric signal S16a. The pressure amplifier 16B amplifies the signal S16a from the pressure sensor 16A, and amplifies the amplified pressure signal S16.
b is output. The pressure pulse wave amplifier 16D receives the signal S16b from the pressure amplifier 16B, extracts a vibration component, and outputs a cuff pressure vibration arterial wave signal S16d. AD above
The converter 16C receives the analog pressure signal S16b from the pressure amplifier 16B and the analog cuff pressure pulse arterial wave signal S16d from the pressure pulse wave amplifier 16D, converts them into digital, and outputs a digital signal S16c. I do.

The CPU 10 as the blood pressure determination calculating means 4 is provided by the cuff pressure converting and cuff pressure shaking artery wave extracting means 16.
Inputs, as a digital signal S16C from the AD converter 16C, a cuff pressure-corresponding signal and a cuff pressure oscillating artery wave signal for detecting a predetermined time point serving as a reference for blood pressure determination. Thereby, as shown in FIG. 5B, the CPU 10 determines that the first inflection point I1 of the trend curve V of the cuff pressure oscillating arterial wave.
The cuff pressure P is measured at times t5 and t6 when the pressure is detected and at times t6 and t8 when the second inflection point I2 is detected, and the blood pressure at the time of pressurization (C1) and the time of depressurization (C2) is determined (Ps1 ,
Pd1, Ps2, Pd2) and a systolic blood pressure value and a diastolic blood pressure value are calculated based on the blood pressure determination result.

The operation of the second embodiment according to the second invention having the above configuration will be described below with reference to FIGS. 4 and 5B. The difference from the first embodiment (FIG. 3) according to the second invention is that
The operation of the cuff pressure conversion and cuff pressure oscillation arterial wave extraction means 16 connected to the input side of the blood pressure determination calculation means 4 and the operation of the blood pressure determination calculation means 4 using the cuff pressure oscillation artery wave as a reference signal for blood pressure determination. is there. That is, the cuff pressure is converted into an electric signal S16a by the pressure sensor 16A connected to the cuff 1 and constitutes the cuff pressure conversion and cuff pressure oscillation arterial wave extraction means 16, and the cuff pressure is inputted to the pressure amplifier 16B. Analog pressure signal S16b directly from the AD converter 4C
At the same time, the cuff pressure arterial wave signal S16d from which the vibration component is extracted by the pressure pulse wave amplifier 16D is input to the AD converter 16C. As a result, the CPU 10 as the blood pressure determination calculating means 4 sends, from the AD converter 16C, a signal corresponding to the cuff pressure and a cuff pressure oscillating artery wave signal for detecting a predetermined time point which is a reference for blood pressure determination. As a digital signal S16C. Therefore, as shown in FIG. 5B, the CPU 10 determines the time points t5 and t7 at which the first inflection point I1 of the trend curve V of the cuff pressure oscillating arterial wave is detected and the second time point t5.
The cuff pressure P is measured at times t6 and t8 when the inflection point I2 is detected, and the blood pressure is determined at the time of pressurization (C1) and at the time of decompression (C2) (Ps1, Pd1, Ps2, Pd2). (1) explained in the first embodiment (1-A) of the invention
Equation (Ps = a · Ps1 + b · Ps2) and equation (2) (P
d = c · Pd1 + d · Pd2), the systolic blood pressure value P
s and the diastolic blood pressure value Pd are calculated.

Furthermore, in the first embodiment according to the second invention and (3) Second Embodiment (FIG. 4), when performing repeated blood pressure determination (FIG. 5 (C)), the first first time By operating both the pressurizing means 2 and the depressurizing means 3, the blood pressure determination calculating means 4 makes a blood pressure judgment at the time of pressurizing and at the time of depressurizing, and operates only the pressurizing means 2 for the second and subsequent times. Thus, the blood pressure determination calculation means 4 performs only the blood pressure determination at the time of pressurization, and for example, the expression (3) (Ps (n) described in the first invention)
= (A + bPs2 / Ps1) Ps1 (n)),
(4) Equation (Pd (n) = (c + dPd2 / Pd1) P
d1 (n)), a systolic blood pressure value Ps (n) and a diastolic blood pressure value Pd (n) are calculated.

[0031]

As described above , according to the present invention, the blood pressure is determined both at the time of pressurization and at the time of depressurization, and the average value or correction value is used as the measurement result. it is possible to reduce the influence on the speed of the measurement accuracy (FIG. 5 (a), the FIG. 5 (B)), the measurement result of the reproducibility is high, and provides shift less have non invasive blood pressure measuring device so
I can . In addition, since the systolic blood pressure value is determined when the cuff pressure rises and falls (FIGS. 5A and 5B), the cuff is not pressurized more than necessary, and unnecessary pain is not given to the subject. I did not give it. Therefore, high reproducibility of the measurement results, deviation is small, and can provide a non-invasive blood pressure measurement apparatus which does not give an unnecessary pain to the subject. Further, according to the present invention, particularly when the measurement is repeatedly and automatically performed (FIG. 5C), only the blood pressure determination at the time of pressurization needs to be performed for the second and subsequent times. The burden on the subject can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a first embodiment of the first invention.

FIG. 2 is a view showing a second embodiment of the first invention.

FIG. 3 is a view showing a first embodiment of the second invention.

FIG. 4 is a view showing a second embodiment of the second invention.

FIG. 5 is an operation explanatory diagram of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cuff 2 Pressurization means 3 Decompression means 4 Blood pressure judgment calculation means

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Sosei Futama 2-35-8 Hongo, Bunkyo-ku, Tokyo Fukuda Electronics Co., Ltd. Hongo Office (56) References JP-A-63-130043 (JP, A) JP-A-1-256930 (JP, A) JP-A-4-2639 (JP, A) JP-A-2-82940 (JP, A) JP-A-4-180728 (JP, A) JP-B-39-13529 JP, B1) (58) Field surveyed (Int. Cl. ⁷ , DB name) A61B 5/02-5/0295

Claims (13)

(57) [Claims] 1. A cuff 1 for compressing a part of a living body, and a cuff pressure of the cuff 1 increases at a predetermined speed at which a blood pressure can be measured.
Pressurizing means 2 for supplying air to the cuff 1 and lowering the cuff pressure of the cuff 1 at substantially the same speed as the rising speed.
The pressure reducing means 3 for exhausting from the cuff 1 so as to descend, and a signal corresponding to the cuff pressure of the cuff are inputted,
Control with the step and the pressure reducing means and at a predetermined time.
The cuff pressure is measured to determine the blood pressure during pressurization and decompression,
A systolic blood pressure value and a diastolic blood pressure value based on the blood pressure determination result.
And a blood pressure determination calculating means 4 for calculating the blood pressure.
The cuff pressure of full 1 raises pressure performed blood pressure determination of measurement to pressurization of the cuff pressure at a given point in time, the pressure reducing means
By further depressurizing the cuff pressure at approximately the same speed as by pressurization speed the pressurizing means performs blood pressure determination of decompression time by measuring the cuff pressure at a given point in time, the blood pressure before Symbol pressurization
The determination result and the non-invasive blood pressure measurement device and calculates a systolic blood pressure value and the diastolic blood pressure with a mean value of the blood pressure determination result at reduced pressure. 2. A cuff 1 for compressing a part of a living body, and a cuff pressure of the cuff 1 increases at a predetermined speed at which blood pressure can be measured.
Pressurizing means 2 for supplying air to the cuff 1 and lowering the cuff pressure of the cuff 1 at substantially the same speed as the rising speed.
The pressure reducing means 3 for exhausting from the cuff 1 so as to descend, and a signal corresponding to the cuff pressure of the cuff are inputted,
Control with the step and the pressure reducing means and at a predetermined time.
The cuff pressure is measured to determine the blood pressure during pressurization and decompression,
A systolic blood pressure value and a diastolic blood pressure value based on the blood pressure determination result.
And a blood pressure determination calculating means 4 for calculating the blood pressure.
The cuff pressure at the predetermined time is increased by increasing the cuff pressure of the cuff 1
The pressure is measured, the blood pressure at the time of pressurization is determined, and the pressure
The cuff pressure is set to approximately the same speed as the pressurizing speed by the pressurizing means.
Pressure at a given point in time
The measures carried out blood pressure determination at the time of pressure reduction, blood pressure before Symbol pressurization
The correction value of the average value of the determination result and the blood pressure determination result during decompression is
Calculating the systolic and diastolic blood pressure values.
Non-invasive blood pressure measuring device. Wherein the blood pressure determining calculation means 4 is characterized in that predetermined time to measure the cuff pressure is the time the Korotkoff sounds has been time and disappeared occurs claim 1 or請
3. The non-invasive blood pressure measurement device according to claim 2 . That wherein the point at which the first variable time value point is detected and the second inflection point is detected before Symbol trend curve given moment cuff圧振artery waves for measuring the cuff pressure Features and
3. The non-invasive blood pressure measuring device according to claim 1 or 2.
Place . 5. When the blood pressure determination is repeatedly performed, the first 1
Times first is, as before Symbol pressurization performs a blood pressure determination of decompression at the time, the second and subsequent from the next, to make only blood pressure determination before the Symbol pressurization
Noninvasive blood pressure measurement apparatus according to any one of claims 1 to 4, characterized. 6. Before KiKa圧means 2, pressurizing the flow control valve 2
The non-invasive blood pressure measurement device according to any one of claims 1 to 5, comprising A, an air supply pump 2B, and a drive unit 9. 7. Before SL pressure reducing means 3, the vacuum flow control valves 3
1 to claim characterized in that it comprises a A, a drive unit 9
The non-invasive blood pressure measurement device according to claim 6 . 8. Before Symbol blood pressure determination calculating unit 4, CPU 10
8. The method according to claim 1 , further comprising:
Noninvasive blood pressure measurement device crab according. 9. Before SL to the input side of the blood pressure determination calculation means 4, before
Cuff pressure converting means 14 for measuring the pressure in the serial cuff and Koroto
9. The non-invasive blood pressure measurement device according to claim 8, wherein Korotkoff sound recognition means 15 for recognizing Coff sound is connected. 10. A pre-Symbol cuff pressure converting means 14, a pressure sensor 14A, a pressure amplifier 14B, an AD converter 14C
The non-invasive blood pressure measurement device according to claim 9 , further comprising: 11. Before SL Korotkoff sound recognizing means 15, and the Korotkoff sound sensor 15A, Korotkoff sounds amplifier 15B
If, include a band pass filter 15C, a comparator 15D
The non-invasive blood pressure measurement device according to claim 9 or 10, wherein: The input side of 12. Before Symbol blood pressure determination calculation means 4,
Measure the pressure in the cuff and extract the cuff pressure-oscillating artery waves.
The cuff pressure transducer and cuff圧振arterial wave extraction means 16 for output is connected non-invasive blood pressure measuring apparatus according to claim 9, wherein. 13. Before SL cuff pressure transducer and cuff圧振arterial wave extracting means 16, a pressure sensor 16A, the pressure amplifier 16
Including B, a AD converter 16C, and a pressure pulse wave amplifier 16D
13. The non-invasive blood pressure measurement device according to claim 12, wherein: