JPH09299339A - Sphygmomanometer - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To provide a sphygmomanometer which does not cause a measurement error due to a cycle change of a living body and a temperature / body temperature change. In an oscillometric sphygmomanometer, the threshold levels S _s and S _d are changed depending on the time and the time when blood pressure is measured. Regarding the measurement time, for example, from 6 am to 6 pm, the threshold levels S ₂ and S ₃ are used during the day, and from 6 pm to 6 am, the threshold levels S ₁ and S ₄ are used during the night. , Calculate the maximum and minimum blood pressure. For the measurement timing, for example, 4
Threshold levels S ₁ , S from summer to September
₄ , the maximum and minimum blood pressures are calculated using the threshold levels S ₂ and S ₃ for winter from October to March.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sphygmomanometer characterized by blood pressure calculation, and more particularly to a sphygmomanometer that determines blood pressure under conditions for optimal blood pressure determination according to the environment during blood pressure measurement. .

[0002]

2. Description of the Related Art Conventional blood pressure monitors include those using a direct method or an indirect method (Korotkoff sound method, oscillometric method, pulse wave velocity method, tonometry method, volume compensation method, etc.). In general, blood pressure is generally calculated from a fixed coefficient or calculation formula according to an individual.

On the other hand, a living body has one day, one week, one month,
It is known that blood pressure fluctuates with a cycle such as a year, and that blood pressure fluctuates even with temperature and body temperature. This indicates that the cardiac function and blood vessel characteristics in the living body periodically and dynamically change.

[0004]

Therefore, the direct method sphygmomanometer that directly measures the blood pressure is not a problem, but the indirect method sphygmomanometer that measures the blood pressure through the identification of blood vessels does not cause cycle fluctuations in the living body or the temperature.・ Fluctuations in body temperature can cause a large error in blood pressure measurement. Therefore, the present invention has been made in view of such a problem, and an object thereof is to provide a sphygmomanometer that does not cause a measurement error due to a cycle variation of a living body or a temperature / body temperature variation.

[0005]

In order to achieve the above object, a sphygmomanometer according to claim 1 of the present invention comprises a biological signal detecting means for detecting a biological signal and a biological signal obtained by the biological signal detecting means. In a sphygmomanometer including a blood pressure determining unit that determines blood pressure based on a signal, a blood pressure determining condition changing unit that changes a condition for blood pressure determination according to the environment of blood pressure measurement is provided, and the blood pressure determining unit is a blood pressure determining unit. The blood pressure is determined according to the condition changed by the condition changing means.

In the blood pressure monitor according to claim 1, the blood pressure is determined in accordance with the environment at the time of measuring the blood pressure [time / time (or season) at the time of measurement, temperature / body temperature (or temperature difference between temperature and body temperature), etc.]. The conditions (threshold level, conversion curve, etc.) are changed by the blood pressure determination condition changing means, and the optimum blood pressure calculation formula and calculation coefficient according to the measurement environment are used, so that cycle fluctuations and temperature
Measurement errors due to changes in body temperature are reduced and measurement accuracy is improved.

A blood pressure monitor according to a fourth aspect of the present invention is an oscillometric blood pressure monitor, further comprising threshold level changing means for changing the threshold level according to an environment of blood pressure measurement, and the blood pressure determining means is operated by the threshold level changing means. The blood pressure is determined according to the changed threshold level. The blood pressure monitor according to claim 5 is a Korotkoff sound blood pressure monitor,
It is characterized in that it comprises threshold level changing means for changing the threshold level according to the environment of blood pressure measurement, and the blood pressure determining means determines the blood pressure according to the threshold level changed by the threshold level changing means.

According to a sixth aspect of the blood pressure monitor of the pulse wave propagation type blood pressure monitor, the blood pressure conversion function curve changing means is provided for changing the blood pressure conversion function curve according to the environment of blood pressure measurement. The blood pressure is determined according to the blood pressure conversion function curve changed by the blood pressure conversion function curve changing means. The blood pressure monitor according to claim 7, wherein the blood pressure monitor is a volume compensation blood pressure monitor, comprising control curve changing means for changing the control curve according to an environment of blood pressure measurement, and the blood pressure determining means,
The blood pressure is determined according to the control curve changed by the control curve changing means.

A sphygmomanometer according to claim 8 is a tonometry type sphygmomanometer, comprising blood pressure value conversion curve changing means for changing the blood pressure value conversion curve in accordance with the environment of blood pressure measurement, and the blood pressure determining means means The blood pressure is determined according to the blood pressure value conversion curve changed by the conversion curve changing means. The sphygmomanometer according to claims 4 to 8 relates to an oscillometric type, a Korotkoff sound type, a pulse wave propagation type, a volume compensation type, and a tonometry type, respectively, which are important factors for determining blood pressure (threshold level, blood pressure conversion). Since the function curve, the control curve, and the blood pressure conversion curve) are changed according to the blood pressure measurement environment, the measurement error due to the cycle variation of the living body and the temperature / body temperature variation is reduced as described above.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments. A block diagram showing the configuration of the sphygmomanometer according to one embodiment is shown in FIG. The sphygmomanometer shown here includes a compression band (for example, a cuff) 10 that compresses a predetermined part of a living body, a pump 11 that supplies air to the compression band 10, a pressure sensor 12 that detects the air pressure of the compression band 10, and a compression band. A slow exhaust valve 13 for slowly exhausting the air inside 10, an air pipe 14 connecting the compression zone 10, the pump 11, the pressure sensor 12 and the slow exhaust valve 13, control of driving the pump 11, and the pressure sensor 12 CP that performs signal input and calculation to determine blood pressure
U15, a display 16 for displaying the determined blood pressure value, a power ON / OFF switch 17, a clock 18 for measuring the month / day / hour, and a setting switch 1 for setting this clock 18.
9 or a date and time input unit 29 for inputting the date and time in place of the clock 18 and the setting switch 19. However, in this embodiment, only the case where the clock 18 and the setting switch 19 are used will be described.

In the sphygmomanometer of this embodiment, the portion surrounded by the dotted line is the indirect blood pressure measuring unit 20, and the indirect blood pressure measuring unit 20 in FIG. 1 is the case of the oscillometric blood pressure monitor. The indirect blood pressure measuring unit 20 can be replaced. For example, FIG. 2 shows the case of the Korotkoff sound type blood pressure monitor. However,
The same reference numerals are given to the same elements. In this case, the compression band 10 has a Korotkoff sound microphone 10a, and the Korotkoff sound is captured from the microphone 10a of the compression band 10 attached to the living body.

FIG. 3 shows the case of a pulse wave type blood pressure monitor.
Then, the electrocardiographic sensor 21, the electrocardiographic amplifier 22, and the light emitting element 23
And a light receiving sensor 24. In (b), the pair of light emitting elements 23a and the light receiving sensor 24a, and the pair of light emitting elements 2
3b and the light receiving sensor 24b. FIG. 4 shows a case of a volume-compensation sphygmomanometer, in which the compression band 10 has a light emitting element 23 and a light receiving sensor 24 built therein and has a control valve 25. FIG. 5 shows a case of a tonometry sphygmomanometer in which the pressure sensor 12 is built in the sensor fixed probe 26. These indirect blood pressure measurement units 20 are not different from the conventional ones, and can be replaced with the blood pressure monitors of the respective systems.

Next, in each type of sphygmomanometer, the principle of operation for changing the conditions for blood pressure determination according to the blood pressure measurement environment will be described. During the daytime (winter), the blood vessels become harder due to the autonomic periodicity of the living body in preparation for stress compared to the average annual and daytime blood vessel hardness, and at night (summer),
Since the stress is lower than in the daytime (winter), the blood vessels become soft due to the autonomic periodicity of the living body. Here, in the conventional indirect sphygmomanometer that measures the blood pressure through the elastic characteristic of the blood vessel, the periodic fluctuations caused by the living body are all measurement errors. Therefore, by canceling the nighttime (summer) / daytime (winter) periodic fluctuations caused by the living body, it is possible to eliminate the measurement error and improve the measurement accuracy.

The case where the conditions are changed according to the environment in each type of sphygmomanometer will be specifically described. FIG. 6 shows a case of an oscillometric blood pressure monitor. Here, the lower diagram in FIG. 6 shows the process of gradually increasing the pressure of the compression band wrapped around the outer periphery of the living body including the artery from the systolic blood pressure and then gradually reducing the pressure. At that time, a graph showing the envelope curve connecting the peaks within one beat of the waveform is processed so that the waveform bottom point of the pulsation signal fluctuation component of the artery detected by the compression zone is on the baseline. FIG.

In the oscillometric sphygmomanometer, generally, a threshold level S _s (for example, H _max × 0.3) uniformly obtained from the maximum value (H _max ) of the envelope is the time when the envelope exceeds the plus direction. The compression band pressure of is the maximum blood pressure,
The minimum blood pressure is the compression band pressure at the time when the envelope exceeds the threshold level S _d (for example, H _max × 0.5) in the negative direction.

In this embodiment, the threshold levels S _s and S are set according to the time and the time when the blood pressure measurement is performed.
Change _d . Regarding the measurement time, for example, from 6 am to 6 pm, the threshold level S ₂ , S is set as daytime.
₃ is used, and from 6 pm to 6 am, the threshold levels S ₁ and S ₄ are used as nighttime, and the maximum and minimum blood pressures are calculated. For the measurement timing, for example, from April to 9
The maximum and minimum blood pressures are calculated by using the threshold levels S ₁ and S ₄ as the summer until the month and the threshold levels S ₂ and S ₃ as the winter from October to March.

Threshold levels S ₁ , S ₂ ,
S ₃ and S ₄ are S ₁ = S _s × 0.9 S ₂ = S _s × 1.1 S ₃ = S _d × 1 from threshold levels S _s and S _d statistically obtained during the day or throughout the year. It is calculated as 1 S ₄ = S _d × 0.9.

FIG. 7 shows the case of the Korotkoff sound type blood pressure monitor. As in the case of the oscillometric sphygmomanometer, the pressure in the compression band wrapped around the outer periphery of the living body including the artery is sufficiently increased from the systolic pressure and then gradually reduced. FIG. At that time, the graph showing the blood flow sound signal (Korotokov sound signal) of the artery detected by the microphone on the compression zone is the upper diagram of FIG. 7.

In the Korotkoff sound sphygmomanometer, generally, the first blood flow sound signal exceeds the threshold level S (for example, KH _max × 0.1) uniformly obtained from the maximum value (KH _max ) of the blood flow sound signal. The compression pressure at the time of is the maximum blood pressure,
The compression band pressure at a point one beat before the threshold level S is first dropped below the threshold level S after reaching the threshold level is defined as the minimum blood pressure.

In this embodiment, the threshold level S is changed depending on the time and the time when the blood pressure measurement is performed.
Regarding the measurement time, for example, from 6 am to 6 pm, the threshold level S ₂₁ is used as the daytime, and from 6 pm to 6 am, the threshold level S ₂₂ is used as the night to determine the maximum and minimum blood pressures. calculate. Regarding the measurement time, for example, from April to September, the threshold level S ₂₂ is used as the summer, and from October to March, the threshold level S ₂₁ is used as the winter to calculate the maximum and minimum blood pressures.

The threshold levels S ₂₁ and S ₂₂ are calculated as S ₂₁ = S × 0.9 S ₂₂ = S × 1.1 from the threshold level S statistically obtained during the day or throughout the year.

FIG. 8 shows the case of a pulse wave type blood pressure monitor.
An electrocardiographic electrode is attached to a living body (a symmetrical position on the front of the chest centering on the heart, left and right upper limbs, etc.), and an electrocardiographic R wave is detected. The electrocardiographic R wave is used as the ejection point of the pulsation propagation of the arterial system due to the heartbeat, and the photoplethysmogram is generated in the peripheral blood vessels such as the earlobe or the fingertip.
A pulsation detection sensor such as an impedance plethysmograph or a piezoelectric element detects the pulsation synchronized with the heartbeat that has propagated to the peripheral arteries, and the time difference (pulse wave propagation time: PTT) is measured. It is also possible to use a pulsation detection sensor similar to a peripheral blood vessel instead of the electrocardiographic signal, detect pulsation on an artery central to the peripheral blood vessel, and measure PTT from the time difference. By measuring the measurement section length, the pulse wave velocity (PWV) can be easily calculated from the PTT,
The blood pressure value is calculated from the correlation between the PWV and the maximum / minimum blood pressure. Further, here, since the measurement section is constant when it is used in an individual, the relative value of the pulse wave velocity can be obtained only by taking the reciprocal of PTT, and within the general blood pressure fluctuation range, PTT itself and blood pressure The blood pressure value can be estimated from the correlation with the value. Therefore, in this embodiment, FIG. 8 shows a case where the correlation between the PTT and the blood pressure value for which blood pressure can be easily calculated is used.

In principle, the pulse wave propagation sphygmomanometer can measure only the relative change in the blood pressure value from a certain reference point, so the blood pressure is measured and calibrated beforehand by another blood pressure measuring device. The PTT change from this calibration point is taken as the blood pressure conversion function curve l _s , l _d
To calculate the systolic blood pressure and diastolic blood pressure, respectively. In this embodiment, the blood pressure conversion function curves l _s and l _d are changed depending on the time and the time when the blood pressure measurement is performed.
Regarding the measurement time, for example, the blood pressure conversion function curves l ₂ and l ₄ are used as the daytime from 6 am to 6 pm, and the blood pressure conversion function curves l ₁ and l ₃ are used as the night time from 6 pm to 6 am Is used to calculate the systolic and diastolic blood pressure.
Regarding the measurement timing, for example, blood pressure conversion function curves l ₁ and l ₃ are used as the summer season from April to September, and blood pressure conversion function curves l ₂ and l ₄ are used as the winter season from October to March. , Calculate the maximum and minimum blood pressure.

The blood pressure conversion function curves l ₁ , l ₂ ,
l ₃ and l ₄ are blood pressure conversion function curves l _s and l _d that are statistically obtained during the day or throughout the year, and l _s = f _1s (PTT-PTT ₁ ) + SYS ₁ l _d = f _1d (PTT-PTT ₁ ) + DIA ₁ , l ₁ = 1.1 × f _1s (PTT-PTT ₁ ) + SYS ₁ l ₂ = 0.9 × f _1s (PTT-PTT ₁ ) + SYS ₁ l ₃ = 1.1 × f _1d It is calculated as (PTT-PTT ₁ ) + DIA ₁ l ₄ = 0.9 × f _1d (PTT-PTT ₁ ) + DIA ₁ . However, f _1s and f _1d are functions passing through the origin.

FIG. 9 shows the case of a volume compensation type sphygmomanometer.
The lower part (lower left) of FIG. 9 shows a process of gradually increasing the pressure of the compression band wrapped around the outer periphery of the living body including the artery from the systolic blood pressure and then gradually decreasing the pressure. At that time, a blood vessel volume sensor (impedance plethysmograph,
A graph showing a change in the volume of the artery detected by the photoelectric pulse wave sensor) is shown in the upper part (upper left) of FIG.

In a volume-compensated sphygmomanometer, in general, the compression band pressure P ₁ at the maximum value (MH _max ) of the pulsation change of the arterial volume and MH
volume level V ₁ obtained uniformly from _max (for example MH
_max / 3 + MH _off ) (P ₁ ,
The blood pressure is calculated by controlling the compression band pressure so that the volume signal is placed on the control curve l _bp (the upper right diagram in FIG. 9) passing through V ₁ ). That is, the controlled compression band pressure itself becomes the real-time blood pressure value itself of the sub-compression artery.

In this embodiment, the control curve l _bp is changed depending on the time and the time when the blood pressure measurement is performed. Regarding the measurement time, for example, from 6 am to 6 pm, the control curve l ₂₁ is used for the daytime, and from 6 pm to 6 am for the night, the control curve l ₂₂ is used to determine the maximum and minimum blood pressures. calculate. Regarding the measurement time, for example, the control curve l ₂₂ is used as the summer from April to September, and the control curve l ₂₁ is used as the winter from October to March to calculate the maximum and minimum blood pressures.

As for the control curves l ₂₁ and l ₂₂ , if the control curve l _bp obtained statistically during the day or throughout the year is _calculated from l _bp = f ₂ (P-P ₁ ) + V ₁ , then l ₂₁ = It is calculated as 0.9 × f ₂ (P−P ₁ ) + V ₁ l ₂₂ = 1.1 × f ₂ (P−P ₁ ) + V ₁ . However, f ₂ is a function that passes through the origin.

FIG. 10 shows a case of a tonometry type sphygmomanometer.
You. Suitable with a sensor-fixed probe on the artery near the skin surface
The pressure sensor is fixed so that the pressure is not too high. Suitable for pressing
If so, the blood as shown on the pressure sensor signal axis in FIG.
A pressure pulsation signal (wave1) can be obtained. Above pressure
The signal output of the sensor depends on the pressure of the sensor fixed probe
Since the baseline fluctuates, in order to obtain the absolute value of blood pressure
Is the other blood measured simultaneously with this tonometry sphygmomanometer.
It is necessary to calibrate with the blood pressure value by the pressure measuring device. here
Detect the peak and bottom of wave1 and pass through the calibration points.
Blood pressure conversion curve l _s2, L_d2From the highest blood pressure, the highest
Low blood pressure is calculated.

In this embodiment, when blood pressure measurement is performed
The above-mentioned blood pressure conversion curve l_s2, L_d2change
I do. Regarding the measurement time, for example, from 6 am to 6 pm
Blood pressure conversion curve l₃₂, L₃₄use
However, from 6 pm to 6 am it is converted to blood pressure at night.
Curve l₃₁, L₃₃Calculate the maximum and minimum blood pressure using
You. For the measurement period, for example, from April to September is summer
Blood pressure conversion curve l as season₃₁, L₃₃Using October
From March to March, the blood pressure conversion curve l₃₂, L ₃₄use
To calculate the maximum and minimum blood pressure.

The blood pressure conversion curves l ₃₁ , l ₃₂ , l ₃₃ ,
l ₃₄ is a blood pressure value conversion curve l _s2 , l _d2 which is statistically obtained during the day or throughout the year, and l _s2 = f _3s (PV-PV _s ) + SYS ₂ l _d2 = f _3d (PV-PV _d ) + DIA ₂ If _calculated from: l ₃₁ = 1.1 × f _3s (PV- PV _s ) + SYS ₂ l ₃₂ = 0.9 × f _3s (PV- PV _s ) + SYS ₂ l ₃₃ = 1.1 × f _3d (PV - is obtained as _{PV d) + DIA 2 l 34} = 0.9 × f 3d (PV- PV d) + DIA 2. However, f _3s and f _3d are functions passing through the origin.

FIG. 11 is a general flow chart showing the processing procedure of the blood pressure monitor configured as described above. First, in step (hereinafter abbreviated as ST) 1, the indirect blood pressure measurement unit (see reference numeral 20 in FIG. 1) is used to collect biological signals such as electrocardiogram and arterial pulsation and information such as compression band pressure. In ST2, the current time, season, etc. are read from the information of the clock (see reference numeral 18 in FIG. 1). Next, in ST3, it is determined which category (day / night, summer / winter) the present belongs to. ST
Based on the determination in 3, in ST4 and ST5, the optimum calculation coefficient or calculation function for each category is selected as described above. Then, in ST6, the minimum blood pressure value and the maximum blood pressure value are calculated using the set calculation coefficient or calculation function and the biological signal. Then, in ST7, the calculated blood pressure value is displayed.

The sphygmomanometer of the above embodiment changes the conditions for blood pressure determination depending on the time and timing of blood pressure measurement as the environment for blood pressure measurement. The case where the temperature and body temperature at the time of blood pressure measurement are used will be described below. To do. When the air temperature / body temperature (or the temperature difference between air temperature and body temperature) rises, humans autonomously soften the hardness of blood vessels as compared to the average blood vessel hardness, thereby increasing blood flow and Promotes heat dissipation from the surface. Conversely, when the air temperature / body temperature (or the temperature difference between the air temperature and the body temperature) becomes low, the blood flow rate is decreased by increasing the hardness of the blood vessel autonomously as compared with the average blood vessel hardness. Suppresses heat dissipation from the surface. Therefore, in the conventional indirect sphygmomanometer that measures the blood pressure through the elastic characteristic of the blood vessel, the vascular elasticity variation caused by the temperature / body temperature (or the temperature difference between the air temperature and the body temperature) causes all measurement errors. However, the measurement accuracy can be improved by canceling the vascular elasticity variation caused by the temperature / body temperature (or the temperature difference between the air temperature and the body temperature) with the skin surface temperature 25 ° C. and the atmospheric temperature 20 ° C. as boundaries. .

Next, a specific example of changing the calculation coefficient and the calculation function according to the air temperature and the body temperature when the blood pressure is measured in each type of sphygmomanometer will be described. FIG. 12 is a block diagram showing the configuration of the blood pressure monitor. This blood pressure monitor is basically
The blood pressure monitor has the same configuration as that of the blood pressure monitor shown in FIG. 2 except that it has the temperature sensor 28 or the temperature input unit 30, and does not have the clock 18 and the setting switch 19 or the date / time input unit 29 of FIG.
Further, the indirect blood pressure measuring unit 20 can be similarly replaced with a blood pressure monitor of each system. Each method (Oscillometric method,
Blood pressure determination in a blood pressure monitor of Korotkoff sound type, pulse wave propagation type, volume compensation type, tonometry type is shown in FIGS.
Since it is as shown in 0, only the point that the calculation coefficient and the calculation function are changed according to the temperature and the body temperature will be described. However, in this embodiment, only the case where the temperature sensor 28 is used will be described.

That is, in the oscillometric sphygmomanometer of FIG. 6, the threshold levels S _s and S _d are changed according to the temperature / body temperature (or the temperature difference between the air temperature and the body temperature) during blood pressure measurement. Regarding the body temperature, for example, if the skin surface temperature under the squeezing zone is 25 ° C. or lower, it is regarded as low temperature and the threshold levels S ₂ , S ₃
If the temperature is 25 ° C. or higher, the blood pressure (highest and lowest blood pressure values) is calculated using the threshold levels S ₁ and S ₄ as high temperature. Regarding the air temperature, for example, if the atmospheric temperature is 20 ° C. or lower, the threshold levels S ₂ and S ₃ are used as low temperatures,
If the temperature is 20 ° C or higher, the temperature is high and the threshold levels S ₁ and S _{4 are}
Is used to calculate the blood pressure. The threshold levels S ₁ , S ₂ , S ₃ and S ₄ are obtained as described above.

In the Korotkoff sound sphygmomanometer of FIG. 7, the threshold level S is changed according to the temperature / body temperature (or the temperature difference between the air temperature and the body temperature) at the time of blood pressure measurement. For body temperature,
For example, if the skin surface temperature under the compression zone is 25 ° C. or lower, the threshold level S ₂₁ is used as the low temperature, and if it is 25 ° C. or higher, the threshold level S ₂₂ is used as the high temperature to calculate the blood pressure. Regarding the air temperature, for example, if the atmospheric temperature is 20 ° C. or lower, the threshold level S ₂₁ is used as a low temperature, and if it is 20 ° C. or higher, the threshold level S ₂₂ is used as a high temperature to calculate the blood pressure. The threshold levels S ₂₁ and S ₂₂ are obtained as described above.

When measuring the blood pressure, the pulse wave type blood pressure monitor of FIG.
Depending on the temperature and body temperature (or the temperature difference between air temperature and body temperature)
Blood pressure conversion function curve l_s, L_dTo change. About body temperature
Is low if the skin surface temperature under the compression zone is 25 ° C or lower, for example.
Blood pressure conversion function curve l as temperature _Two, L_FourAt 25 ℃
If the temperature is higher than the above, the blood pressure conversion function curve l is regarded as high temperature.₁, L_Threeuse
Then, the blood pressure is calculated. For temperature, for example,
If the temperature is 20 ° C or lower, the temperature is low and the blood pressure conversion function curve l_Two, L
_FourIs used, the blood pressure conversion function is
Line l₁, L_ThreeIs used to calculate the blood pressure. Blood pressure
Conversion function curve l ₁, L_Two, L_Three, L_FourAs above
Required.

When measuring blood pressure, the volume-compensated blood pressure monitor of FIG.
Depending on the temperature and body temperature (or the temperature difference between air temperature and body temperature)
Control curve l_bpTo change. For body temperature, for example, compression
If the skin surface temperature under the belt is 25 ° C or less, the temperature is controlled to be low.
Line l_{twenty one}Control curve l
_{twenty two}Is used to calculate the blood pressure. For temperature, for example
For example, if the atmospheric temperature is 20 ° C or lower, it is regarded as a low temperature and the control curve l_{twenty one}use
Control curve l_{twenty two}Use
Then, the blood pressure is calculated. The control curve l_{twenty one}, L _{twenty two}Is before
You will be asked for as stated.

In the tonometry type sphygmomanometer of FIG.
Depends on the temperature and body temperature at regular time (or the temperature difference between the body temperature and body temperature)
Is blood pressure conversion curve l_s2, L_d2To change. About body temperature
For example, if the skin surface temperature under the compression band is 25 ° C or less,
Blood pressure conversion curve l as low temperature ₃₂, L₃₄At 25 ℃
If it is higher than the above, the blood pressure value conversion curve 1₃₁, L₃₃Use
Then, the blood pressure is calculated. Regarding temperature, for example,
If the temperature is 20 ° C or lower, the temperature is low and the blood pressure conversion curve 1₃₂, L₃₄To
Use it, and if it is over 20 ℃, it will be high temperature and blood pressure conversion curve
l₃₁, L₃₃Is used to calculate the blood pressure. The blood pressure value
Conversion curve l₃₁, L₃₂, L₃₃, L₃₄As described above
Can be

A general flow chart showing the processing procedure of this blood pressure monitor is shown in FIG. The flow chart of FIG. 13 is basically the same as that of FIG. 11, but in ST2, the current temperature,
The temperature sensor measures the temperature of the body or the temperature difference between the air temperature and the body temperature (Fig. 1
2 (see reference numeral 28), and in ST3, it is different in that which category (high temperature / low temperature) the present belongs to.

[0041]

As described above, according to the first aspect of the present invention.
According to the described sphygmomanometer, the conditions for blood pressure determination (threshold level) are determined according to the environment at the time of blood pressure measurement [time / time (or season) at the time of measurement, temperature / body temperature (or temperature difference between temperature and body temperature), etc.] ,
(Conversion curve etc.) is changed by the blood pressure determination condition changing means,
Since the optimal blood pressure calculation formula and calculation coefficient according to the measurement environment are used, it is possible to calculate the blood pressure that corresponds to changes in vascular characteristics due to cycle fluctuations of the living body or temperature / body temperature fluctuations.・ Measurement error due to body temperature fluctuation is reduced and measurement accuracy is improved. Moreover, such an effect can be easily obtained only by adding a clock capable of monitoring the month / day time or a temperature sensor capable of monitoring the temperature / body temperature to an ordinary blood pressure monitor.

According to the sphygmomanometers of claims 4 to 8, in the oscillometric type, Korotkoff sound type, pulse wave propagation type, volume compensation type, and tonometry type, respectively,
Important factors for determining blood pressure (threshold level, blood pressure conversion function curve, control curve, blood pressure conversion curve) are changed according to the blood pressure measurement environment.
Measurement error due to body temperature fluctuation is reduced, and measurement accuracy is improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a sphygmomanometer (indirect blood pressure measuring unit is an oscillometric type) according to an embodiment.

FIG. 2 is a block diagram showing a configuration when an indirect blood pressure measuring unit in FIG. 1 is of Korotkoff sound type.

FIG. 3 is a block diagram (a) showing an example of a configuration in the case where the indirect blood pressure measuring unit in FIG. 1 is a pulse wave propagation type, and a block diagram (b) showing another example.

FIG. 4 is a block diagram showing a configuration in the case where the indirect blood pressure measuring unit in FIG. 1 is a volume compensation type.

5 is a block diagram showing a configuration in the case where the indirect blood pressure measuring unit in FIG. 1 is a tonometry type.

FIG. 6 is a diagram illustrating the principle of changing the threshold level for blood pressure determination when the indirect blood pressure measuring unit is an oscillometric type.

FIG. 7 is a diagram illustrating the principle of changing the threshold level for blood pressure determination when the indirect blood pressure measuring unit is of the Korotkoff sound type.

FIG. 8 shows a case where the indirect blood pressure measuring unit is a pulse wave type,
It is a figure explaining the principle which changes the blood pressure conversion function curve for blood pressure determination.

FIG. 9 shows a case where the indirect blood pressure measuring unit is a volume compensation type,
It is a figure explaining the principle which changes the control curve for blood pressure determination.

FIG. 10 is a diagram illustrating a principle of changing a blood pressure value conversion curve for determining blood pressure when the indirect blood pressure measuring unit is a tonometry type.

FIG. 11 is a general flow diagram showing a processing procedure of the sphygmomanometer of the same embodiment.

FIG. 12 is a block diagram showing a configuration of a sphygmomanometer (the indirect blood pressure measuring unit is an oscillometric type) according to another embodiment.

FIG. 13 is a general flow diagram showing a processing procedure of the sphygmomanometer of the same embodiment.

[Explanation of symbols]

 10 compression band 12 pressure sensor 15 CPU 18 clock 19 setting switch 20 indirect blood pressure measurement unit 28 temperature sensor 29 date and time input unit 30 temperature input unit

Claims (8)

[Claims] 1. A biological signal detecting means for detecting a biological signal,
In a sphygmomanometer including a blood pressure determining unit that determines blood pressure based on a biological signal obtained by the biological signal detecting unit, a blood pressure determining condition changing unit that changes a condition for determining blood pressure according to an environment of blood pressure measurement is provided. The blood pressure determining means comprises
A sphygmomanometer characterized in that the blood pressure is determined according to the condition changed by the blood pressure determination condition changing means. 2. The sphygmomanometer according to claim 1, wherein the condition for determining the blood pressure is a threshold level. 3. The sphygmomanometer according to claim 1, wherein the condition for determining the blood pressure is a conversion curve. 4. A biomedical signal detecting means for compressing a predetermined part of a living body and detecting a biomedical signal in the process of changing the compression pressure,
Among the pulsating components of the pressure signal obtained by the biological signal detecting means, in an oscillometric sphygmomanometer including a blood pressure determining means for determining the blood pressure from the compression pressure corresponding to the magnitude of the pulsating component corresponding to the threshold level. A sphygmomanometer characterized by comprising threshold level changing means for changing the threshold level according to an environment of blood pressure measurement, wherein the blood pressure determining means determines blood pressure according to the threshold level changed by the threshold level changing means. 5. A biological signal detecting means for pressing a predetermined part of a living body and detecting a biological signal in the process of changing the pressing pressure,
In the Korotkoff sound signal obtained by the biological signal detecting means, in a Korotkoff sound sphygmomanometer equipped with a blood pressure determining means for determining the blood pressure from the pressure corresponding to the magnitude of the Korotkoff sound signal corresponding to the threshold level, A sphygmomanometer comprising: a threshold level changing means for changing the threshold level according to an environment of blood pressure measurement, wherein the blood pressure determining means determines blood pressure according to the threshold level changed by the threshold level changing means. 6. A blood pressure is determined by using a biological signal detecting means for detecting a pulse wave from a living body and a blood pressure conversion function curve relating to the propagation time of the pulse wave and the converted blood pressure value obtained by the biological signal detecting means. In a pulse wave propagation type blood pressure monitor including blood pressure determining means, blood pressure converting function curve changing means for changing the blood pressure converting function curve according to the environment of blood pressure measurement is provided, and the blood pressure determining means includes blood pressure converting function curve changing means. A blood pressure monitor which determines blood pressure according to the blood pressure conversion function curve changed by. 7. A biomedical signal detecting means for compressing a predetermined part of a living body and detecting a biomedical signal in the process of changing the compression pressure,
In a volume-compensated sphygmomanometer comprising a blood pressure determining means for determining a real-time blood pressure from a volume pulse wave signal obtained by this biological signal detecting means and a control curve of compression pressure, the control curve according to the environment of blood pressure measurement. A blood pressure monitor comprising: a control curve changing unit for changing the blood pressure, wherein the blood pressure determining unit determines the blood pressure according to the control curve changed by the control curve changing unit. 8. A biological signal detecting means for compressing a predetermined part of a living body and detecting a biological signal in the compressed state, and a blood pressure value conversion curve relating to the pressure signal and the converted blood pressure value obtained by the biological signal detecting means. In the tonometry sphygmomanometer provided with a blood pressure determining means for determining the blood pressure using a blood pressure value conversion curve that passes through a separately measured calibration point, a blood pressure value that changes the blood pressure value conversion curve according to the environment of blood pressure measurement. A conversion curve changing means, and the blood pressure determining means,
A blood pressure monitor for determining blood pressure according to a blood pressure value conversion curve changed by the blood pressure value conversion curve changing means.