JPS628732A - Digital electronic hemomanometer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to an electronic finger blood pressure monitor, and particularly to an electronic finger blood pressure monitor equipped with a plurality of cuffs that can individually compress two or more fingers.

(B) Prior Art The inventor of this application has developed an electronic finger blood pressure monitor that uses a pneumatic cuff (rubber air bag) similar to a cuff type blood pressure monitor, and has already filed a patent application No. 4 (Special Patent Application). (Gan Sho 60-78651).

The electronic finger blood pressure monitor of this earlier application includes a cuff for compressing the finger, a pneumatic system for increasing or decreasing the air pressure of the cuff, a cuff pressure sensor for detecting the cuff pressure, and a cuff pressure change process. A pulse wave sensor detects pulse wave information of the cuff, and a blood pressure determination means determines the blood pressure value based on the cuff pressure from the cuff pressure sensor and the pulse wave information from the pulse wave sensor. , pressurize the cuff with a pneumatic system, press the finger from the surroundings, detect the pulse wave component in the process of changing cuff pressure with a pulse wave sensor, divide this pulse wave component into each pulse wave, The pulse wave amplitude of each pulse wave is determined from each level of each pulse wave, and the blood pressure value is determined from the pulse wave amplitude of each pulse wave and the cuff pressure.

(c) Problems to be solved by the invention In the above-mentioned electronic finger blood pressure monitor, the detected pulse wave component is obtained in the process of changing cuff pressure, and its amplitude changes with the change in cuff pressure. Changes greatly.

For this reason, it is possible to determine blood pressure by detecting the pulse wave amplitude, but on the other hand, pulse wave components whose amplitudes vary greatly are used to segment the pulse wave to determine the pulse wave amplitude. In view of the above, Yuko's invention has the problem of not being able to perform pulse wave segmentation with high precision, resulting in the inability to obtain accurate pulse wave amplitude, and the inability to perform highly accurate measurement.
Therefore, it is an object of the present invention to provide an electronic finger blood pressure needle that can accurately extract each pulse wave amplitude and perform highly accurate measurement.

(d) Means and Effects for Solving Problems The electronic finger blood pressure monitor of the present invention has a cuff 5A for compressing the first finger, and a cuff 5A for compressing the first finger. a pneumatic system 6A including a pressurizing means for supplying air pressure to the cuff and an exhaust means for exhausting the air pressure in the cuff; a pressure sensor 7A for detecting the air pressure in this pneumatic system; A first detection system 1 includes a pulse wave sensor 8A that detects finger pulse wave components during the process, a cuff 5B for compressing the second finger, and an air pressure control system to maintain the air pressure of the cuff constant. A pneumatic system 6B including a pressurizing means for supplying air and an evacuation means for exhausting air from the cuff; a pressure sensor 7B for detecting the air pressure of this pneumatic system; A second detection system 2 consisting of a pulse wave sensor 8B that detects a pulse wave component, and a pulse wave sensor 8B of the first detection system that detects the pulse wave component of the first detection system in synchronization with the pulse wave component output from the pulse wave sensor of the second detection system. a pulse wave information detection means 3 for deriving the sensor; and a blood pressure determination means for determining a blood pressure value from the pulse wave information detected by the pulse wave information detection means and the air pressure detected by the pressure sensor of the first detection system. It is composed of 4.

In this electronic finger blood pressure monitor, the first and second fingers are pressurized and compressed by separate cuffs. In the second detection system 2, the cuff 5B is kept at a constant pressure (for example, about the average blood pressure), and a pulse wave component with a constant amplitude is obtained from the pulse wave sensor 8B. This pulse wave component has a constant amplitude and is stable.

On the other hand, in the first detection system 1, the cuff 5A is slowly evacuated from a predetermined pressure, and during this slow evacuation process, the pulse wave component is detected by the pulse wave sensor 8A. This pulse wave component is synchronized with the stable pulse wave component detected by the second detection system 2, and the pulse wave information detection means 3
The blood pressure value is determined based on this pulse wave information and the cuff pressure from the cuff 5A.

(E) Examples The present invention will be explained in more detail with reference to Examples below.

FIG. 2 is an external perspective view of an electronic finger blood pressure monitor showing an embodiment of the present invention.

This embodiment of the digital finger blood pressure monitor includes a main body 11 and a main body 1.
1 and a cuff portion 12 connected to the cuff portion 1 by a cord wire 13.

On the top surface of the case 21 of the main body 11, there are keys such as a power switch 22, a start switch 23, and a clear switch 24.
Pressure setting value changeover switch 2 for switching the pressurization setting value
5. A display 26 is provided for displaying blood pressure values and the like. Also, although not shown inside the case 21,
An MPU (microprocessor unit), other electronic circuits, a pressure pump, etc. are provided.

The cuff part 12 has a cylindrical cuff storage case 27 with an oval cross section.
, two cylindrical cuffs 28Δ and 28B1 provided inside the storage case 27, and a pulse wave sensor 29A129B provided at an appropriate position on the inner hole wall of each cuff.

The cuff 28A and the cuff 28B are air bags made of rubber and have a cylindrical outer shape, and as shown in FIG.
It is connected to the main body 11 by rubber tubes 30A and 30B. Further, as the pulse wave sensors 29A and 29B, reflective photoelectric sensors are used, each consisting of light emitting elements 31A and 31B and light receiving elements 32A and 32B. These pulse wave sensors 29A, 29B are connected to the electronic circuit section of the main body 11 via lead wires 33A, 33B. Therefore, the cord wire 13 connects to the rubber tubes 30A, 30B and the lead wires 33A, 33B.
It is a collection of

When the finger is compressed by the cuff 28A (28B), the volume of the artery changes, so of the amount of light emitted from the light emitting element 31A (31B), the scene received by the light receiving element 32A (32B) changes, and the pulse Wave components are detected.

FIG. 4 is a circuit block diagram of the electronic finger blood pressure needle according to the embodiment, and the same numbers as in FIGS. 2 and 3 indicate corresponding components and circuits, respectively.

The cuff 28A includes a pressure sensor 34A, a slow exhaust valve 35A, and a rapid exhaust valve 36, which are installed in the main body 1 through a rubber tube 30A.
A, and a pressurizing pump 37A is connected to the cuff 28A via a non-return valve 38A.

Air pressure detected by the pressure sensor 34A is amplified by an amplifier 39A, and is taken into the MPU 41 via an A/D converter 40A.

The light emitting element 31A of the pulse wave sensor 29A is turned on by a command from the MPU 41, and the pulse wave component obtained from the light receiving element 32A is amplified by the amplifier 42A, passes through the A/D converter 40, and is also taken into the MPU 41. It looks like this.

In addition, the second detection system 2 has the following features, except that it does not have a slow exhaust valve.
A cuff 28B, a rapid exhaust valve 36B, a pressurizing pump 37B, a check valve 38B, amplifiers 39B, 42B, an A/D converter 40B, etc. are connected and configured in the same manner as in the first detection system 1.

The MPU 41 has a built-in program that is executed according to a predetermined procedure, and has a function of turning on/off the pressure pumps 37A and 37B.
Function to turn on/off quick exhaust valves 36A, 36B, A/
A function that switches the D converters 4OA and 40B to capture and store the cuff pressure and pulse wave data of the rain detection system, and a function that captures the pulse wave data from the first detection system in synchronization with the pulse wave component captured from the second detection system. A function of deriving the input pulse wave component as pulse wave information (pulse wave information detection means), this pulse wave information and the first detection system 1
It is equipped with a function (blood pressure value determining means) to determine the blood pressure value based on the cuff pressure.

Further, the determined blood pressure values, that is, the systolic blood pressure (SYS) and the diastolic blood pressure (DIA) are output from the MPU 41 and displayed on the display 26.

Next, referring to the control flow diagrams shown in FIGS. 5 and 6,
The operation of the digital finger sphygmomanometer according to the above embodiment will be explained.

When the power switch 22 is pressed, the system is initialized, such as clearing the memories in the MPU 41 [Step ST]
(hereinafter abbreviated as ST)■].

Before starting the measurement, the measurer inserts, for example, his index finger and middle finger into the inner holes of the cuffs 28A and 28B, and turns on the start switch 23. As a result, the determination of “Is the start switch ON” of Sr2 becomes YES, and the pressure pump 37B
to pressurize the cuff 28B and increase the cuff pressure to 100
mmHg (see Figure 8) (Sr1). Thereby, as shown in FIG. 8, a pulse wave of approximately constant amplitude is obtained from the pulse wave sensor 29B.

Following the driving of the pressurizing pump 37B, the pressurizing pump 37A is also driven by Sr1, and the cuff 28A is pressurized to a set value (preset by the pressurizing set value changeover switch 25) (see FIG. 7). . When pressurized to the set value, the pressurizing pump 37
A is turned off, and slow exhaust is started by the slow exhaust valve 35A (Sr1).

Next, check whether the base line of the pulse wave (pulse wave sensor 29A output) is stable (Sr6)L, and when it enters a stable state, read the pulse wave component level aB of the second detection system 2 (Sr1).
, this pulse wave component level a13 is the threshold value at
It is determined whether or not the value is hB or more (Sr1). If the pulse wave component level aB is smaller than the threshold value athB,
Return to Sr1, read aB, and recompare with athB (
Sr1.5T8). Then, the pulse wave component level aB is at
This process of Sr1 and Sr1 is not repeated until hB is exceeded.

When aB reaches athB, the pulse wave component level aB exceeds the threshold value athB, and from this point to the next point where the same < aB exceeds athB, pulse waves are divided into one pulse wave. Become.

If the determination of Sr1 is YES, then set the pulse wave counter i to 1 (5T9), start the 10m5ec timer (STI O), and set the threshold as the maximum value amaxA and minimum value aminA of the pulse wave component of the detection system 1. The value athA is stored and the flag is set to "1" (STI 1). This flag is the pulse wave component level a
When B exceeds athB, it becomes "1", and when it becomes smaller than athB, it becomes "0".

The above 10m5ec timer is used for so-called sampling, which takes in data every time up. Therefore, we wait at 5T12 until this 10m5ec timer times up, and when it times up, we start the timer again (ST13) and the pulse wave component level aA%a of detection system 1 and detection system 2 at that time.
B and the cuff pressure p of the detection system 1 are read. (STIO).

Next, it is determined whether the read cuff pressure p is smaller than 40 mm 11 g. If the cuff pressure p is smaller than 40 mmHg, data reading is terminated and the process proceeds to the process shown in FIG. 6, which will be described later.

If the cuff pressure p is not smaller than 40 mmHg (during normal measurement), the judgment of 5T15 "is p < 40 mmHg" is No, and the aA and amaxA read this time are compared, and the judgment is made as to "is aA>aIIlaxA". Perform (S716
), and aA is amax A (= a thA>
If it is larger, this aA is stored as a new amaxA (ST17), but if aA is smaller than amaxA, 5T17 is skipped.

Also, aA and aminA are compared, and it is determined whether aA<aminA (ST18). In this case, aA is ami
If it is smaller than n A (= a thA), this aA is newly stored as aminA (ST19), and if aA is larger than aminA, 5T19 is skipped.

Next, the pulse wave component level aB of the detection system 2 is compared with its threshold value athB, and it is determined whether or not aB>athB (Sr20). Initially, this determination is YES, and then it is determined whether the flag is "0" (Sr22). Initially, the flag is set to "1" in ST1'l, so
This determination is No, and the process returns to 5T12. Then, the processes from 5T12 to 5T22 are performed again, and the maximum value amaxA and minimum value aminA of the pulse wave component of the detection system 1 are updated.

Eventually, when the pulse wave component level aB of the detection system 2 becomes smaller than the threshold value athB, "aB>a" of 5T20.
thB?” is No, and then the flag is set to “0”.
(Sr21), return to STI 2. Thereafter, the processes from 5T12 to ST21 are repeated every 10 m5ec, and the maximum value amaxA and minimum value aminA of the pulse wave component of the detection system 1 are updated and the cuff pressure p is recorded.

The pulse wave component level aB of the detection system 2 is the threshold value at
When it becomes larger than hB again, the determination at 5T20 becomes YES, and further, at 5T22, it is determined whether flag="O" or not. Since the flag has already been set to "0" in Sr21, this determination is YES. This means that one pulse wave has passed when aB reaches athB (pulse wave separation). Therefore, the difference value between amax A and amin B that has been stored up to that point is calculated, and the pulse wave (i
= 1) as the amplitude a iA (a, A), and the corresponding cuff pressure pi (p+) 5T23),
Pulse wave number i is +1 (i=2) (Sr24), S
Return to TI 1.

5TII, amax ASamin A again ath
Initial memory in B, set flag to 1'', and then 5TI2
By repeating the process from ~5T22, the maximum value amaxA, minimum value amin, and A of the pulse wave components of the next pulse wave are updated, and the cuff pressure p is stored. When data for one pulse wave is obtained, 5T2
3, the amplitude aiA (axA) of the pulse wave is determined and stored.

As described above, the pulse wave component is divided into pulse waves based on the output of the detection system 2, and the amplitude ai of each pulse wave of the pulse wave component of the detection system 1 is determined in synchronization with the five pulse wave divisions.

Slow evacuation of the cuff of detection system 1 progresses, and the cuff pressure p reaches 4Qmm.
When it becomes smaller than Hg, the determination at 5T15 becomes YES, and the process moves to blood pressure determination processing from 5T25 onwards.

The distribution of the pulse wave amplitude aiA and cuff pressure pi stored up to that point with respect to the pulse wave number i is shown in FIG. 9(a).
(According to bl.

Next, the blood pressure determination process after 5T25 will be explained.

First, at 5T25, the systolic blood pressure PSYS and the maximum pulse wave value ama
xc storage area) to O and pulse wave number i to 1. Then, it is determined whether i=1, that is, the amplitude value a of the first pulse wave, is greater than or equal to the threshold value ath (ST26)
.

As illustrated in FIG. 9(a), if al<ath, the determination is No, the process jumps to ST31, and i is +1 (i=2).
Then, it is determined whether or not i exceeds N (the number of stored pulse wave data) (ST32), and if it does not, the process returns to 5T26, and this time it is determined whether or not the pulse wave value a2 is greater than or equal to the threshold value ath (ST26). ). Then, repeat the processing of 5T26, ST31.5T32 until at≧ath,
Compare ai and ath. In FIG. 9(a), this process is performed up to a4.

If the pulse wave amplitude ai exceeds the threshold value at6, as shown in a4 in the example of FIG. 9 (al), the determination of 5T26 is Y.
ES, and then it is determined whether Psvs = 'O or not (
ST 27), if PSYS = 0, it means that the systolic blood pressure has not been determined yet, and the cuff pressure pi (I)4 in the example in Figure 9(b) at this point is taken as the systolic blood pressure p svs. Store (ST28).

Subsequently, it is determined whether the pulse wave amplitude ai is greater than or equal to a maX (ST29). This determination is for extracting the maximum value of the pulse wave amplitude, and the pulse wave amplitude at is the threshold value a.
At the time when th is exceeded, since 5T2F> and amax←0, this judgment becomes YES, and the pulse wave amplitude ai (a4) is first stored as amax, and the corresponding cuff pressure pi at that point is It is stored as Pmean (mean blood pressure) (ST30). Then, at 5T31, add 1 to i (i=5), and return to 5T26 via 5T32. Thereafter, since the pulse wave amplitude at is larger than ath, the determination is YES in 5T26, and in 5T27, p sv
Since s has already been determined, the decision is NO, and 5T2
Skip 8 and move on to 5T29. As illustrated in FIG. 9(a), when the pulse wave amplitude ai is increasing as i increases, the determination of "at ≥ a max" in 5T29 becomes YES, and the current pulse wave amplitude at is the maximum amplitude a l1
lax, and the current cuff pressure pi is the mean blood pressure P m
Each is updated and stored as ean (ST30). Similar processing is continued while the pulse wave amplitude i increases as i increases.

Eventually, when the pulse wave amplitude ai decreases with respect to the increase in i, the determination at 5T29 becomes NO, skipping 5T30 and proceeding to 5T31. From then on, even if i increases, a ma
x, P mean are not updated, so the mean blood pressure P
The mean is determined. After that, when i exceeds N+1,
The judgment of ST32 is YES, and then (3x Pme
an -Psvs)/2 and calculate the diastolic blood pressure P
DIA is determined (ST33).

The determined systolic blood pressure and diastolic blood pressure are displayed on the display 26 (5T34), and the rapid exhaust valve 36A is turned on.
Finish the measurement.

In the above embodiments, the index finger and middle finger of the left hand are assumed to be inserted, but other fingers may be used, and the fingers may be inserted on the left hand and the right hand.

Further, in the above embodiment, the cuff pressure at the time when the pulse wave amplitude exceeds the threshold value is the systolic blood pressure, the cuff pressure at the time when the pulse wave amplitude reaches the maximum value is the average blood pressure, and (3×mean blood pressure - systolic blood pressure)/ Although the diastolic blood pressure is determined from 2, other blood pressure determination algorithms may be used.

(F) Effects of the Invention According to the present invention, first and second detection systems each having a cuff pressure and a pulse wave sensor are provided, and the second detection system obtains a pulse wave component using a constant cuff pressure. This pulse wave component is used to separate the pulse wave components of the first detection system to obtain the pulse wave amplitude for blood pressure determination, and the second detection system separates the pulse wave components at a constant cuff pressure. Since this method allows stable pulse wave segmentation and accurate pulse wave amplitude to be obtained, accurate blood pressure measurement can be performed.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a schematic configuration of the present invention, and FIG. 2 is an external perspective view of an electronic finger blood pressure monitor showing an embodiment of the present invention.
Fig. 3 is an enlarged perspective view of the cuff part of the electronic blood pressure monitor for use by the same authority, Fig. 4 is a circuit block diagram of the electronic blood pressure monitor for the use of the same authority, and Figures 5 and 6 are for the same authority. FIG. 7 is a control flow diagram for explaining the operation of the digital blood pressure monitor for digital blood pressure monitors; FIG. Time chart of cuff pressure changes and pulse wave components of the second detection system of the electronic blood pressure monitor, Figure 9(a) (
b) is a diagram showing an example of changes in pulse wave amplitude and cuff pressure of the electronic blood pressure monitor for Ii. 1: First detection system, 2: Second detection system, 3: Pulse wave information detection means, 4: Blood pressure determination means, 5A/5B: Cuff,
6A/6B: Pneumatic system, 7A/7B=pressure sensor, 8A
・8B: Pulse wave sensor 1 Figure 1

Claims (1)

[Claims] (1) A pneumatic system including a cuff for compressing the first finger, a pressurizing means for supplying air pressure to this cuff, and an exhaust means for exhausting air from the cuff, and detecting the air pressure of this pneumatic system. a first detection system for compressing a second finger; a pneumatic system including a cuff, a pressurizing means for supplying air pressure to maintain the air pressure of the cuff at a constant level, and an exhaust means for exhausting air from the cuff; a second detection system consisting of a pulse wave sensor that detects a pulse wave component; and a pulse wave sensor of the first detection system in synchronization with the pulse wave component output from the pulse wave sensor of the second detection system. pulse wave information detecting means for deriving the sensor output as pulse wave information; pulse wave information derived by the pulse wave information detecting means; and the first
An electronic finger sphygmomanometer comprising a blood pressure determining means for determining a blood pressure value from the air pressure detected by the pressure sensor of the detection system.