JPH0375040A - Electronic hemadynamometer - Google Patents

Abstract

PURPOSE:To display an adequate pressure reducing speed for a detected person by providing an informing means with a classifying mean which classifies the pressure reducing speed in a predetermined range, and a display means which displays a predetermined display mark corresponding to the classified result. CONSTITUTION:First in a step S90, a pulse wave of a person is detected, and then in a step 91, a pressure value at this time is stored in a register P1. Next in a step S92, when the next pulse wave is detected, the detection advances to a step S93, and a pressure value at this time is stored in a register P2. In a step S94, a difference DELTAP between the registers P1 and P2 is taken, multiplied by a predetermined coefficient alpha, converted into a pressure reduction value Ps per 1 pulse and stored in a register Ps. The value of Ps is checked for 2mmHg or 5mmHg in steps S95, S96 and in the case of the value smaller than 2mmHg, a left triangular mark is displayed in a step S99, while in the case of the value larger than 5mmHg, a right triangular mark is displayed in a step S98. Further, in the case of the value in 2mmHg or more and 5mmHg or less, two squared marks are displayed with a pressure reducing speed informed of right or wrong.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electronic sphygmomanometer, and particularly to an electronic sphygmomanometer that measures blood pressure from cuff pressure based on input Korotkoff sounds and/or pulse wave signals. be.

[Prior Art] In conventional electronic blood pressure monitors, when displaying the rate of pressure reduction during pressure reduction, the rate of pressure reduction per unit time is displayed numerically.

[Problems to be Solved by the Invention] However, with such conventional display of decompression speed, it is difficult to judge whether the numerical value is appropriate or not.

Furthermore, since the value does not match the pulse rate, there is a problem in that it is impossible to determine whether the decompression rate is suitable for the subject.

The present invention eliminates the drawbacks of the conventional art, and provides an electronic blood pressure monitor that converts whether or not the decompression rate is appropriate into a rate per pulse, and also displays the appropriate decompression rate for the subject as a mark display instead of a numerical display. do.

[Means for Solving the Problem] In order to solve this problem, the electronic blood pressure monitor of the present invention is an electronic blood pressure monitor that measures blood pressure from cuff pressure based on input Korotkoff sounds and/or pulse wave signals. The apparatus includes a calculation means for calculating a decompression rate per predetermined pulse rate of the subject based on a pulse wave, and a notification means for notifying the calculated decompression rate.

Here, the notification means includes a classification means for classifying the decompression speed into a predetermined range, and a display means for displaying a predetermined display mark corresponding to the classification result.

[Example] Hereinafter, an example of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the electronic blood pressure monitor of this embodiment. FIG. 2 is a diagram schematically showing the appearance of the electronic blood pressure monitor of this embodiment. This electronic sphygmomanometer is composed of a Korotkoff detection section 50 that detects Korotkoff sounds, a pressurizing section 40 that applies pressure, and a control section main body 1o that administers control.

The control unit body 10 uses 4 or 8 inch rechargeable batteries 11, which are four 1 or 2 inch rechargeable batteries connected in series, as a power source, and supplies a predetermined voltage to the necessary parts of the control unit body 10 through a power supply control 12. ing.

This rechargeable battery 11 can be charged with a charger 60, and its performance as a portable electronic blood pressure monitor has been improved. 16th
Figure A shows the shape and structure of the rechargeable battery 11 of this embodiment. Normally, a rechargeable battery is assembled using several nickel plates, each pole is spot welded, and the lead wires are attached at the end. Place such a battery in the battery holder 11
If it is inserted into a, an erroneous insertion will occur. Therefore, the 16th B
As shown in the figure, a metal plate with a protrusion in the center is spot welded to the negative pole to prevent incorrect insertion. The reason for attaching it to the negative pole is that spot welding is not possible due to the shape of the positive pole.

In FIG. 16A, 11-8 to 11-4 are 1.2V rechargeable batteries, 111 is a positive electrode, 112 is a negative electrode,
113 is a shrink tube as a protective tape, 114 is a protrusion for preventing incorrect insertion, and 115 is a rechargeable battery 11-1 to 11-4.
These are a spacer and a liquid leakage prevention plate for stabilizing the contact between the positive and negative electrodes. In Figure 16B, 1
14a is a projection, 114b is a conductive member, and 114c is a projection for spot welding.

A power switch 13 for turning on the power is provided on the outside of the main body. Furthermore, a mode switch 15 is provided on the outside of the main body for operating the electronic blood pressure monitor in a plurality of modes. It also includes a display (LCD) 29 for externally displaying the blood pressure value, mode, depressurization speed, rechargeable battery voltage, etc., and a buzzer 30 for notifying the end of measurement or an error.

Control of the control unit main body 10 is performed by the A/D conversion unit 1 and the control unit 2.
2, a Korotkoff sound pulse wave recognition section 23, and a display driving section 24.

The CPtJ 20 is a 1-chip LSI, and has an external memory 25 consisting of a ROM for storing programs and a RAM for auxiliary storage. CPU 20 has external memory 25
While decompressing the arm cuff by controlling the exhaust valve 28 via the drive unit 27 according to the program in the program, the pulse wave amount from the microphone 51 of the Korotkoff sound detection unit 50 is transmitted to the filter amplifier 16 and the A/D conversion unit 21. Based on the recognition of the Korotkoff sound by the Korotkoff sound pulse wave recognition unit 23, the pressure in the pressurizing unit 40 at each time point is detected via the pressure detection unit 18, the amplifier 19, and the A/D conversion unit 26. The pressure at the beginning of the Korotkoff sound is defined as the systolic blood pressure, and the time at which the Korotkoff sound disappears is defined as the diastolic blood pressure.

Note that the reference power supply section 17 includes a Δ/D converter 21°26.91
as a reference for a pressure sensor, a constant current source for a pressure sensor, or as a baseline for Korotkoff sounds. 1st
FIG. 7 shows an example of the configuration of the reference electrode section 17. The power supply voltage from the rechargeable battery 11 is directly supplied to the amplifier and microcomputer through the power switch 13 as a driving power source.

On the other hand, a more stable potential is supplied to each of the above-mentioned parts from the reference electrode part 17, which is made up of a reference voltage regulator 17a and a resistor 17b.

The pressurizing section 40 receives air from the exhaust valve 28 of the main body 10.
Microphone 51 from exhaust pipe and filter amplifier 16
A cuff 41, a constant speed exhaust valve 42, a manual exhaust valve 43, a rubber bulb 44, and a tube 45 connecting these are connected to the main body 10 by a tube 70 of a predetermined length including a lead wire to the
It consists of. Here, the constant speed exhaust valve 42 is provided so as to be able to manually set the blood pressure at -111, the exhaust valve 43 is for exhausting air from the cuff 41, and the rubber bulb 44 is for manual pressurization.

FIG. 3 is a flowchart showing the basic operation procedure of the electronic blood pressure monitor of this embodiment.

First, in step S1, the device is initialized by, for example, opening the exhaust valve 28 and setting the pressure inside the cuff to O. A measurement mode is selected in step S2. In particular, in this example, there is a mode in which blood pressure is automatically measured, and a mode in which only pressure values are displayed, allowing a doctor to manually measure blood pressure.

If the mode is only for pressure display, proceed to step S7.
The device only displays pressure values without measuring blood pressure.

In the case of the blood pressure measurement mode, the process proceeds to step S3, where the rubber bulb monitors the start of depressurization after pressurization, and determines this as the start of blood pressure measurement.In step S4, it is first determined that there is insufficient pressurization.
Blood pressure is measured in step S5, and after the measurement is completed, the measurement results are displayed in step S6. In this embodiment, step S
Improvements have been made over the past in the determination of insufficient pressurization in Step 4 and the blood pressure measurement in Step S5, as well as the pressure reduction adjustment, power supply, and the like.

Each feature of this embodiment will be described in detail below. Although each part will be explained independently, these functions may be provided in duplicate.Mode Selection Function> FIG. 4 shows a flowchart of measurement in this embodiment.

When the power is turned on by the power switch 13, step S
At step 10, the valve of the manual electronic blood pressure monitor is opened and the pressure sensor is set to zero. In step S1l, when the power is turned on, the measurement mode set switch 15 is set to the microcomputer 20.
is confirmed, and the measurement mode is determined to be A, B, or C in step S13. Step S14. S15. Measurement for each mode is executed in S16, and in step S17, the change in the mode changeover switch 15 is checked, and the process returns to step S13.

Each mode A is shown in FIG. 5A, FIG. 5B, and FIG. 5C.

The processing routines of B and C are briefly shown below.

In this embodiment, the A mode is a normal measurement mode, and during the depressurization process by the constant speed exhaust valve 42 after being pressurized by the rubber bulb 44 in step S20, the occurrence of Korotkoff sound is detected for two consecutive beats in step S21. In this case, the first Korotkoff sound is taken as the systolic blood pressure. If the pressure continues to decrease further and two consecutive Korotkoff sounds cannot be detected in step S22, the last Korotkoff sound is taken as the diastolic blood pressure. The measurement results are displayed in step S23, and since the measurement is now complete, the exhaust valve 28 or the operator opens the manual exhaust valve.

The B mode is a pressure display mode, in which the pressure is only displayed in step S24 in the same way as a mercury sphygmomanometer, but blood pressure is not measured. This mode is used when a doctor manually measures blood pressure using a stethoscope.

C mode is the auscultation gap mode, and step S25. S
The determination of the systolic blood pressure in 26 is the same as the A mode, but when the Korotkoff sound cannot be detected for 5 consecutive beats when determining the diastolic blood pressure, the last Korotkoff sound is taken as the diastolic blood pressure,
Displayed in step S28. This prevents errors in measuring diastolic blood pressure due to auscultation gap, and is used for patients with significant auscultation gap.

Here, the measurement mode changeover switch 15 is designed to be changed sequentially for each switch input, but it cannot be changed during measurement. Blood pressure can be measured.

Determination of insufficient pressurization> FIG. 6 is a timing chart showing the principle of determination of insufficient pressurization in this embodiment.

From the pressure signal 80 inputted from the pressure detection section 18 and converted into a digital value by the A/D conversion section 26, a gate 81 for Korotkoff sound recognition is created using a minimum point 80a and the next point 80b at the same level. . In this gate 81, Korotkoff sounds are extracted by comparing the digital pulse wave signal 83 input from the microphone 51 via the A/D converter 21 with a predetermined threshold level 82. On the other hand, noise is also extracted outside the gate 84 by comparison with a predetermined threshold level 82. Here, if the level of the Korotkoff sound signal 83 is higher than the threshold value 82 from the second gate after a delay of 1 second from the start of decompression, it is set as "1", and when it is lower, it is set as "O".
When expressed as a binary value of "1010", that is, when Korotkoff sounds are extracted twice in succession and the noise during this period is smaller than a predetermined level, it is determined that the pressurization is insufficient.

Furthermore, in the case of "1111", the level of the threshold value 82 is raised and the determination is made again to determine whether or not the value becomes "1010". Note that this judgment may be repeated a predetermined number of times while increasing the level, and the pattern to be judged again is "1111".
In addition to "1011" and "111-0", you can also add "1011" and "111-0".

Further, in this embodiment, the threshold value inside the gate is the same as the threshold value outside the gate, but they may have different values.

FIG. 7A shows a flowchart for determining insufficient pressurization in this embodiment.

When the power is turned on, the electronic sphygmomanometer opens the valve and zero-sets the pressure sensor in step S31. After being pressurized by a pump or rubber bulb, it enters a depressurization process and determines whether the pressurization is insufficient. When the pressurization is finished, steps S32 to 3
Proceed to step 33 and wait 1 second for the pressure fluctuation to subside, then detect one pulse wave. Start the actual measurement from the second beat,
In the processing in steps 334 to S37, the pulse wave signal is larger than the predetermined threshold value A within the gate of the second beat of the pulse wave and within the gate of the third beat, and the pulse wave signal is larger than the predetermined threshold A at the gate of the second beat of the pulse wave and outside the gate of the third beat of the pulse wave. If the noise level of the pulse wave signal outside the gate is smaller than the threshold value A, that is, if it is a "1010" pattern, step S38
It is determined that the pressurization is insufficient, and a pressurization insufficient flag is set in step S39.

In this case, if the noise level outside the gate of the second and third beats is greater than the threshold value A, that is, "1111", the process advances from step S40 to step S41, and the threshold value is set to B (BAA), again. The processing in steps S34 to S37 and the determination in step S38 are performed, and if the result is "1010", it is determined that pressurization is insufficient.

FIG. 7B is a flowchart showing the gate processing in steps S34 to S37. In step S51, the beak-to-beak of the Korotkoff sound signal inside and outside the gate is detected, and in step S52, the beak-to-beak is compared with a threshold value. The flag is set to 1" in step S53, and if it is smaller, the flag is set to "O" in step S54.

<Measurement of diastolic blood pressure only> In the electronic sphygmomanometer of this embodiment, even if systolic blood pressure cannot be measured due to insufficient pressurization, etc., the measurement continues, and only the diastolic blood pressure is measured and displayed. Therefore, it is also possible to measure only the diastolic blood pressure value.

FIG. 8 shows a flowchart of this embodiment.

When the power is turned on, the manual electronic blood pressure monitor opens the valve in step S60, sets the pressure sensor to O, and sets the counter to C.
Clear. In the decompression process after being pressurized by the rubber ball, the process proceeds from step S63 to 364, and step S
If the occurrence of two consecutive Korotkoff sounds is detected in step S75, the first Korotkoff sound is determined as the systolic blood pressure in step S76. If the pressure continues to decrease and two consecutive Korotkoff sounds cannot be measured in step S81, the last Korotkoff sound is determined as the diastolic blood pressure in step S83.

This ends the measurement, so anything over 0 that opens the exhaust valve is normal measurement, and if the Korotkoff sound signal comes in consecutively at the second and third beats of the start of measurement during the depressurization process, the process starts from step S69. Proceeding to S70, it is determined that pressurization is insufficient, and "-m=" is displayed on the systolic blood pressure display section.

In this embodiment, instead of stopping the measurement at that point, it is determined that there is no systolic blood pressure, and the process proceeds to step S77, where only the diastolic blood pressure is measured, and after the measurement, only the diastolic blood pressure is displayed. When "111" is displayed on the systolic blood pressure display, if the rubber bulb is used again to pressurize the systolic blood pressure, the "-m=" on the systolic blood pressure display returns to the pressure display, and measurement can be performed again after the pressure is finished. As such, it is possible to measure only the diastolic blood pressure and normal measurement by repressurization.

Furthermore, there is also a mode in which Korotkoff sound recognition is performed during pressurization, and if there is Korotkoff sound recognition, this is displayed as if the pressure has become higher than the diastolic blood pressure, thereby measuring only the diastolic blood pressure without unnecessary pressurization. .

Display of pressure reduction speed> The electronic blood pressure monitor of this embodiment determines the pressure reduction speed and displays it with a predetermined display mark as shown at 29b in FIG.

FIG. 9 shows the signal output from the pressure sensor. Let ΔP be the differential pressure at the bottom point of this waveform.

Multiplying the ΔP by the coefficient α yields the pressure value Ps per pulse. Alternatively, the timing may be determined using the waveform of FIG. 9 after passing through an AC amplifier, and the pressure value at that time may be used.

That is, Ps is proportional to the rate of pressure reduction for each pulse, and indicates the rate of pressure reduction corresponding to the pulse of the subject.

The pressure value P5 is classified into the following ranges.

■Ps<2mmHg...Slow■2
mmHg≦P8≦5mmHg ...Appropriate■5m
mHg<Ps...Fast The results of the above classification are displayed with marks as shown in Figure 10 to inform the measurer whether the reduced pressure level is appropriate.

FIG. 11 shows a measurement flowchart during measurement.

First, the pulse wave of the subject is detected in step S90, and when this is detected, the pressure value at this time is stored in the register P+ in step S91. Next, in step S92, the next pulse wave is detected, and when detected, the process proceeds to step S93 and the pressure value at this time is stored in register P2. In step S94, P+ and P
The difference ΔP from 2 is taken, and this is multiplied by a predetermined count α to convert it into a pressure reduction value Pt+ per pulse.

Store in. Step S95. In S96, the value of Ps and 2m
Check the size of mHg or 5mmHg, and check the size of 2mmHg.
If it is smaller, display “mark” in step S99, 5
If it is greater than mmHg, a ``mark'' is displayed in step S98, and if it is 2 mmHg or more and 5 mmHg or less, a ``mark'' is displayed to notify the propriety of the decompression speed.

Display of power supply> The electronic blood pressure monitor of this embodiment uses a rechargeable battery 11 as a power source.

This rechargeable battery 11 is charged with a dedicated charger 60, and then placed in a rechargeable battery storage section 11a of the main body and covered with a battery lid 11b. If the battery becomes low after turning on the power, immediately replace the rechargeable battery 11.
When the measurement is completed, turn off the power and
Open the battery cover 11b, take out the rechargeable battery 11a, and replace it with a spare rechargeable battery. You can then turn on the power again and measure your blood pressure.

In this embodiment, the output voltage of the rechargeable battery 11 is constantly monitored, and the state of its decrease is displayed at 29b in FIG. FIG. 15 shows a configuration diagram for monitoring, and FIG. 12 shows a flowchart for determining whether the battery is low.

In step 5100, the A/D converter 91
As shown in the figure, the battery voltage is constantly monitored by the voltage value converted into a digital value (255 to O). When the voltage becomes 4.4 V or less, the process proceeds from step 5lot to step 5102, where the lighting frequency of the low battery mark is set to 2 Hz, and in step 5105, the low battery mark blinks at 2 Hz. If it is higher than 4.4V, proceed to step 5103 and check whether it is lower than 4.5V, and if it is lower than 4.5V, that is, 4.5V and 4.4V.
If it is between, the process proceeds to step 5104, where the lighting frequency is set to IHz, and in step 3105, the low battery mark is blinked at IHz. If it is larger than 4.5v,
Returns without blinking. By controlling as described above, when the voltage falls below 4.5V, the low battery mark blinks at IHz, and when the voltage further decreases to below 4.4V, the low battery mark starts blinking at 2Hz. When the voltage is 4.4v or more and 4.5 or less, IHz again
will start blinking, and when the voltage rises above 4.5V, the low battery mark will disappear.

FIG. 13 shows a flowchart of the level meter display.

If you want to express the battery capacity with a level meter, step 5
The digital value outputted by the A/D converter 91 in step 110 is subjected to a predetermined calculation in step 5111.
~4.2v to 0. By converting into a value of 10 to 0 in IV increments and displaying it with 10 dots, and representing the taken-in battery voltage with a level meter, there is no possibility of measurement errors due to low battery during measurement.

[Effects of the Invention] The electronic blood pressure monitor of the present invention allows the rate of decompression to be adjusted to suit the subject by calculating the rate of decompression per pulse rate (fast decompression for people with a high pulse rate, slow decompression for people with a low pulse rate). Obtainable.

Furthermore, instead of expressing it numerically, the appropriate speed is displayed within a range and with marks for minutes, making it easier to judge.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of the electronic blood pressure monitor of this embodiment, Fig. 2 is a diagram showing the external appearance of the electronic blood pressure monitor of this embodiment, and Fig. 3 is the basic operating procedure of the electronic blood pressure monitor of this embodiment. FIG. 4 is a flowchart showing mode selection in this embodiment. Figures 5A to 5C are flowcharts showing the routine of each mode of this embodiment, Figure 6 is a timing chart showing the principle of determining insufficient pressurization in this embodiment, and Figures 7A and 7B are flowcharts showing the routine of each mode of this embodiment. Flowchart showing the procedure for determining insufficient pressurization in this example. FIG. 8 is a flowchart showing the procedure that enables the measurement of diastolic blood pressure in this example. FIG. 9 is a diagram explaining the principle of measuring the rate of decompression in this example. , Fig. 10 is a diagram showing an example of displaying the decompression speed in this embodiment, Fig. 11 is a flowchart showing the procedure for displaying the decompression speed in this embodiment, and Fig. 12 is a diagram showing an example of displaying the low battery of the power source in this embodiment. Flowchart showing the procedure, Figure 13 is a flowchart showing the procedure for displaying low battery on the other side, Figure 14 is a diagram showing the principle of power supply voltage measurement in this embodiment, Figure 15 is power supply voltage measurement in this embodiment 16A and 16B are diagrams showing the structure of the rechargeable battery of this embodiment. FIG. 17 is a diagram showing the configuration of the reference power supply section of this embodiment. In the figure, 10...control unit main body, 11...rechargeable battery, 12
...Power control, 13...Power switch, 1
4... Reference oscillation section, 15... Mode switch, 16
... Filter amplifier, 17... Reference power supply section, 18.
...Pressure detection section, 19...Amplifier, 20...CPU
, 21... A/D conversion section, 22... control section, 23.
... Brodkoff sound pulse wave recognition unit, 24... display drive unit,
25... External memory, 26... A/D conversion unit, 27
...Drive part, 28...Exhaust valve, 29...Display device (LCD) 30...Buzzer 31...Start switch, 40...Pressure part, 41...Archive (cuff) ), 42... Constant speed exhaust valve, 43... Manual exhaust valve, 44... Rubber bulb, 45... Tube, 50... Korotkoff detection unit, 1... Microphone, 70... It's a tube. Fig. 4 Fig. 5A Fig. 6 Fig. 5C Fig. 7A Fig. 7B Fig. 12 Fig. 2.55V 255 Fig. 14 (R1 wealth R2 Otsu) Fig. 1J15

Claims (2)

[Claims] (1) An electronic sphygmomanometer that measures blood pressure from cuff pressure based on input Korotkoff sounds and/or pulse wave signals, and calculates the decompression rate per predetermined pulse rate of the subject based on the pulse wave. An electronic sphygmomanometer, comprising: calculation means for calculating; and notification means for notifying the calculated pressure reduction rate. (2) The electronic blood pressure monitor according to claim 1, wherein the notification means comprises a classification means for classifying the decompression speed into a predetermined range, and a display means for displaying a predetermined display mark corresponding to the classification result. .