JPH046733Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to an improvement of a continuous blood pressure measuring device that continuously measures the blood pressure value of a living body by compressing the finger of the living body with a cuff.

Prior Art Trends in blood pressure values (trends in changes over time) are widely used as indicators of physical health conditions and as basic information for medical decisions. 2. Description of the Related Art Continuous blood pressure measuring devices that continuously measure blood pressure values by compressing a part of a living body with a cuff are conventionally known. For example, this method uses the oscillometric method, which determines blood pressure based on changes in the size of pulse waves caused by changes in compression pressure with a cuff, and the oscillometric method, which uses ultrasound to detect waves on the arterial surface wall. The blood pressure value is continuously measured by repeatedly performing blood pressure measurement using an ultrasonic method or the like at predetermined time intervals to determine the blood pressure value based on changes in the magnitude of the blood pressure.

By the way, such continuous blood pressure measuring devices generally measure blood pressure by wrapping a cuff around the upper arm, but as mentioned above, each blood pressure measurement puts pressure on the upper arm and reduces blood circulation. Since blood pressure is inhibited, the subject feels uncomfortable each time the blood pressure is measured, and there is a risk that the subject's sleep may be disturbed, especially when blood pressure is measured at night. For this reason, in recent years, blood pressure values have been continuously measured by wrapping a cuff around the finger, which has relatively little influence on the person being measured.

Problems that the invention aims to solve: However, since blood pressure varies slightly depending on the measurement site even in the same subject, the blood pressure value obtained by pressing the finger as described above is could not be equated with the blood pressure value obtained by directly compressing the upper arm. In other words, as mentioned above, it is preferable to look only at the trend of changes in blood pressure over time, but when looking at the absolute size of blood pressure values, the upper arm, which is generally used as basic medical information, is preferable. This had the disadvantage that it could not be treated in the same way as the blood pressure value of the patient.

In addition, for example, blood pressure values in the upper arm are measured during the day and blood pressure values in the fingers are measured only at night, and the blood pressure values in the upper arm and the blood pressure values in the fingers are measured separately to determine the trend of a series of blood pressure values. There was also the problem that the continuity of the trend was lost when

The present invention was developed against the background of the above-mentioned circumstances, and its purpose is to correct the blood pressure value at the finger so that it matches the blood pressure value at the upper arm, and to easily perform the correction. The object of the present invention is to provide a continuous blood pressure measuring device that can obtain continuous blood pressure measurements.

Means for Solving the Problems The gist of the present invention to achieve this purpose is to provide a finger cuff that compresses the finger of a living person and a Continuous blood pressure measurement for continuously measuring the blood pressure value at the finger, comprising a pressure sensor that detects the pressure within the cuff, and a blood pressure value determining means that determines the blood pressure value based on an output signal from the pressure sensor. The device includes: (a) an upper arm cuff that presses the upper arm of the living body; (b) a switching valve that selectively connects the finger cuff and the upper arm cuff to the pressure sensor; and (c) Prior to continuous measurement of the blood pressure value on the finger, the switching valve is placed in a first blood pressure measurement position where the finger cuff and the pressure sensor are communicated to cause the blood pressure value determining means to determine the blood pressure value on the finger. , (d) switching control means for communicating between the upper arm cuff and the pressure sensor and switching between two positions, a second blood pressure measurement position, which causes the blood pressure value determination means to determine the blood pressure value at the upper arm; and (d) blood pressure at the finger. (e) correction value calculation means for calculating a correction value for correcting the blood pressure value at the finger so that the blood pressure value at the finger matches the blood pressure value at the upper arm based on the blood pressure value at the upper arm; The present invention further includes a finger blood pressure value correcting means for correcting the continuously measured blood pressure value of the finger based on the correction value calculated by the correction value calculating means.

In this manner, the switching control means switches the switching valve to two positions, the first blood pressure measurement position and the second blood pressure measurement position, prior to continuous measurement of the blood pressure value on the finger, so that the finger cuff and the second blood pressure measurement position are switched. A pressure sensor is brought into communication so that the blood pressure value determination means determines the blood pressure value at the finger, and an upper arm cuff and the pressure sensor are brought into communication so that the blood pressure value determination means determines the blood pressure value at the upper arm. Ru. and correcting the blood pressure value at the finger so that the blood pressure value at the finger matches the blood pressure value at the upper arm based on the blood pressure value at the finger and the blood pressure value at the upper arm determined as described above by the correction value calculation means. The correction value is calculated, and the finger blood pressure value correcting means corrects the continuously measured finger blood pressure value based on this correction value.

Effects of the invention Therefore, the trend of the blood pressure values obtained in this way is that the magnitude of the blood pressure values is approximately the same as the blood pressure value in the upper arm, so the blood pressure value obtained by compressing the upper arm is It can be treated almost the same as the trend of
It can be widely used as basic medical information. Furthermore, even if a series of blood pressure trends are formed from the blood pressure values measured by compressing the finger and the blood pressure values measured by compressing the upper arm using such a continuous blood pressure measuring device, the above Since the two blood pressure values almost match, the continuity of the trend is not impaired.

Moreover, in the present invention, the switching control means switches the switching valve to the first blood pressure measurement position and the second blood pressure measurement position prior to continuous blood pressure measurement on the finger, so that the finger cuff becomes the pressure sensor. Since the upper arm cuff is connected to a pressure sensor to determine the blood pressure value at the upper arm, the finger cuff and the upper arm cuff are connected to the pressure sensor to determine the blood pressure value at the upper arm. Once the upper arm cuff is attached to a living body, the cumbersome work of alternately connecting the cuff to the pressure sensor, and the connection of the cuff to the pressure sensor, must be performed by a specialist such as a doctor each time. There is no need to change the position on the upper arm. Therefore, the correction value based on the blood pressure value at the upper arm and the blood pressure value at the finger can be obtained without requiring the above-mentioned complicated work and specialized techniques, and a series of corrected blood pressure values at the finger can be obtained. This makes it possible to easily obtain trends.

Furthermore, it is extremely easy to alternately measure the blood pressure on the upper arm and the blood pressure on the finger several times, so it is possible to easily calculate a highly accurate correction value.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

In FIG. 1, 10 is a finger cuff that presses the fingers of a person to be measured, and 12 is an arm cuff that is an upper arm cuff that presses the upper arm of the same person. These cuffs 10 and 12 are connected to the pipe 1 via a switching valve 14.
6. The switching valve 14 is connected to the finger cuff 10.
The finger cuff 10 is communicated with the piping 16.
A first blood pressure measurement position where the blood pressure value at the finger is determined by communicating with the arm cuff 12 and the pressure sensor 18, and a first blood pressure measurement position where the arm cuff 12 and the pressure sensor 18 are communicated by communicating with the arm cuff 12 and the piping 16 to determine the blood pressure value at the arm. It is designed to be able to switch between two positions, including a second blood pressure measurement position where the value is determined.

The piping 16 includes a pressure sensor 18 for detecting the pressure in the cuffs 10, 12, an electric pump 20 for supplying gas into the cuffs 10, 12 to increase the pressure, and a pump 20 for discharging the gas in the cuffs 10, 12. An exhaust valve device 22 is connected to reduce the pressure. The exhaust valve device 22 is composed of, for example, an on-off valve for rapid evacuation and an on-off valve for slow evacuation equipped with a throttle, and is in a closed state to prevent gas from being discharged from the cuffs 10 and 12, and in a closed state to prevent gas from being discharged from the cuffs 10 and 12, and in a closed state to prevent gas from being discharged from the cuffs 10 and 12. A slow exhaust state in which the gas in the cuffs 10 and 12 is gradually exhausted, and the cuffs 10 and 12 are
It is designed to be able to switch between three states, including a rapid exhaust state that rapidly exhausts the gas inside.

The pressure sensor 18 is configured with an amplifier, and amplifies a pressure signal SP representing the pressure of the cuffs 10 and 12 and supplies the amplified pressure signal SP to a low-pass filter 24 and a band-pass filter 26. low pass filter 24
removes vibration components such as pulse waves synchronized with the pulse of the human body from the pressure signal SP and supplies a cuff pressure signal SK representing the static pressure (cuff pressure) of the cuffs 10 and 12 to the A/D converter 28. In contrast to the low-pass filter 24, the band-pass filter 26 extracts only the pulse wave component from the pressure signal SP and supplies the A/D converter 28 with a pulse wave signal SM representing the pulse wave. The A/D converter 28 converts the supplied cuff pressure signal SK and pulse wave signal SM into digital signals, and then supplies them to the I/O port 30.
The I/O port 30 also has a start/stop switch 3.
The start/stop signal SC and the switching signal SS are supplied each time the switching switch 2 and the switching switch 34 are closed.

The I/O port 30 connects a CPU 36, which constitutes a microcomputer, via a data bus line.
Connected to RAM38 and ROM40,
The CPU 36 performs signal processing according to a program stored in advance in the ROM 40 while utilizing the temporary storage function of the RAM 38, and generates drive signals MV1 and MV2 for switching the switching valve 14 and the exhaust valve device 22.
A drive signal MP for operating the electric pump 20 is output from each I/O port 30. Further, a display signal DD is supplied to the display/recording device 42, so that a numerical display or a bar graph representing the average blood pressure value is continuously displayed on the cathode ray tube, and it is also printed and stored on a recording paper. In addition, CPU3
6 is supplied with a pulse signal CK of a predetermined frequency from a clock signal source 44.

Next, the operation of this embodiment will be explained according to the flowchart shown in FIG.

First, when a power switch (not shown) is turned on, an initialization step (not shown) is executed at step S1, and whether the start/stop switch 32 is closed (ON operation) or not, in other words, the start/stop signal SC is determined.
It is determined whether or not it has been supplied. Start stop signal
When SC is supplied, step S2 is then executed and the counting content T of the timer is reset to zero, and the timer then starts counting the pulse signal CK supplied from the clock signal source 44 again.

Next, step S3 is executed, and it is determined whether or not the changeover switch 34 has been closed (ON operation), in other words, whether or not the changeover signal SS has been supplied. If not, step S4 is executed. executed. In step S4, the switching valve 14
The arm cuff 12 and the pipe 16 are switched to communicate with each other, and blood pressure is measured by compressing the upper arm with the arm cuff 12. This blood pressure measurement is based on the conventional oscillometric method. First, the exhaust valve device 22 is switched to the closed state and the electric pump 20 is activated to estimate the cuff pressure of the arm cuff 12. The pressure is increased to a level higher than the average blood pressure value of the subject, and then the electric pump 20 is stopped and the exhaust valve device 22 is switched to the slow exhaust state to gradually exhaust the gas in the arm cuff 12. The cuff pressure is slowly lowered, and in the process of lowering the cuff pressure, the cuff pressure when the magnitude of the pulse wave represented by the pulse wave signal SM reaches its peak is measured as the mean blood pressure value Mn (mmHg). Note that after the mean blood pressure value Mn is measured in this manner, the exhaust valve device 22 is then switched to the rapid exhaust state, and the gas in the arm cuff 12 is rapidly exhausted.

After that, steps S5 and subsequent steps are executed, and in step S5, the display signal DD representing the above-mentioned average blood pressure value Mn is supplied to the display/recording device 42, and a number or bar graph representing the blood pressure value Mn is displayed and a recording paper is displayed. recorded in Further, in step S6, it is determined whether the count content T of the timer has reached the count content Ts predetermined as the time interval when continuously measuring the blood pressure value,
When the counted content T reaches Ts, step S7 is executed. In step S7, it is determined whether the start/stop switch 32 has been operated again (OFF operation), and if it has been operated again, the blood pressure measurement ends, but if it has not been operated again, the process continues from step S1 described above. The above execution is repeated, and the average blood pressure value Mn in the upper arm is continuously measured at the predetermined time interval, and each is displayed and recorded until the start/stop switch 32 is operated again.

On the other hand, in step S3, the changeover switch 34 is closed (turned ON) and the changeover signal SS is
is supplied, steps S8 to S12 are executed instead of step S4. Step S8
In step S11, it is determined whether the correction value ΔK has already been determined, and if the correction value ΔK has already been determined, step S11 is immediately executed.
Since the correction value ΔK has not yet been determined at this stage, steps S9 and S10 are executed prior to step S11.

In the correction value ΔK determination routine in step S9, as shown in FIG. will be held. This is the step S4 mentioned above.
The content is exactly the same as the blood pressure measurement in the arm cuff 12.
By compressing the upper arm, the average blood pressure value Mn (mmHg) in the upper arm is measured. Next, step R3 is executed, and the switching valve 14 is moved to the finger cuff 1.
0 and the pipe 16 are connected,
Blood pressure measurement is performed using the finger cuff 10. This too,
Blood pressure measurement using the arm cuff 12 is performed in exactly the same manner as above, and by compressing the finger with the finger cuff 10, the average blood pressure value Mf (mmHg) at the finger is measured.

Next, step R4 is executed and 1 is added to the contents of counter N. Here, since the content of the counter N was set to 0 in step R1, the content of the counter N becomes 1. Next, step R5 is executed, and it is determined whether or not the content of the counter N is 5. However, since the content of the counter N is 1 as described above, the execution of steps R2 and subsequent steps are repeated. When the content of the counter N becomes 5, in other words, when the blood pressure measurements in steps R2 and R3 are performed five times each, the determination in step R5 becomes YES, and step R6 is then executed.

In step R6, a correction value ΔK is calculated based on the average blood pressure values Mn and Mf measured in steps R2 and R3. That is, first, the average value Mn' and the five average blood pressure values Mn and Mf obtained by five blood pressure measurements are calculated.
Mf' is determined respectively, and the correction value ΔK (mmHg) is calculated according to the following equation (1) ΔK=Mn'−Mf' (1). In this embodiment, this step R6 and the CPU 36, RAM 38, ROM 40, etc. that execute this step correspond to the correction value calculation means.

Once the correction value ΔK is determined in this way, the process returns to FIG. 2 and step S10 is executed, and the correction value ΔK is stored. Subsequently, step S11 is executed, and the average blood pressure value Mf (mmHg) is measured by compressing the finger with the finger cuff 10 in the same manner as the blood pressure measurement in step R3. next,
Step S12 is executed, and step S11 is executed.
The average blood pressure value Mf at the finger measured at
Correct according to the following formula (2) M=Mf+ΔK...(2). As is clear from the above equation (1), the correction value ΔK is the average blood pressure value Mn in the upper arm.
The average Mn′ and the average blood pressure value Mf at the finger
Since it is a difference from Mf', the mean blood pressure value M (mmHg) obtained in this way becomes a value that substantially matches the mean blood pressure value Mn in the upper arm. Note that the steps S4, S11, R2, and R3 correspond to the blood pressure value determining means of the present invention, and the step S12 corresponds to the finger blood pressure value correcting means of the present invention.

Thereafter, the steps from step S5 described above are executed,
In step S5, the corrected mean blood pressure value M is displayed and recorded, and the blood pressure measurement on the finger is repeated at the predetermined time interval until the determination in step S7 becomes YES.
The mean blood pressure value M is continuously measured. Note that when measuring blood pressure from the second time using the finger cuff 10, since the correction value ΔK has already been determined, step S8 is not performed.
The determination in step S8 is YES, and steps S11 and subsequent steps are executed following step S8.

In such a continuous blood pressure measuring device, the trend of the average blood pressure value Mn in the upper arm can be obtained by compressing the upper arm with the arm cuff 12, and in addition, the trend of the average blood pressure value Mn in the upper arm can be obtained by compressing the finger with the finger cuff 10. By doing so, the trend of the average blood pressure value M can be obtained. Moreover, this average blood pressure value M is
This value is a value obtained by correcting the average blood pressure value Mf obtained by pressing the finger using the correction value ΔK determined in step S9 so that it substantially matches the average blood pressure value Mn in the upper arm.

Therefore, the trend in the mean blood pressure value M can be treated almost the same as the trend in the mean blood pressure value Mn obtained by compressing the upper arm, and can be treated not only as a trend in blood pressure change over time. , it can be widely used as basic medical information, etc., even when looking at the magnitude of absolute blood pressure values.

Furthermore, in this embodiment, prior to continuous blood pressure measurement at the finger, the switching valve 14 is switched to the first blood pressure measurement position and the second blood pressure measurement position in step S9, which corresponds to the switching control means of the present invention. As a result, the arm cuff 12 and the pressure sensor 18 are communicated with each other, and the blood pressure value in the arm is determined in step R2.
0 and the pressure sensor 18 are communicated to determine the blood pressure value at the finger in step R3. The cumbersome work of alternately connecting the cuffs 10 and 12 to the pressure sensor 18, and the cuff 10
Furthermore, in connection with changing the connection to the pressure sensor 18 of 12, it is not necessary for a specialist such as a doctor to change the arm cuff 12 to a proper position on the upper arm. Therefore, the correction value based on the blood pressure value in the arm and the blood pressure value in the finger can be obtained without requiring the above-mentioned complicated work and specialized techniques, and a series of corrected blood pressure values in the finger can be obtained. Trends can be easily obtained.

In addition, in this embodiment, since the correction value ΔK is determined by measuring the blood pressure at the upper arm and the blood pressure at the finger five times each, the average blood pressure at the finger can be calculated using a more appropriate correction value ΔK.
Mf will be corrected. In addition, in that case,
Measuring blood pressure in the upper arm and measuring blood pressure in the finger alternately multiple times does not require the above-mentioned complicated work and specialized skills, and can be done very easily, making it easy to perform highly accurate corrections. It is now possible to calculate the value.

In addition, using such a continuous blood pressure measurement device,
For example, during the day, the average blood pressure value Mn may be measured by compressing the upper arm with the arm cuff 12, and at night, the average blood pressure value M may be measured by compressing the finger with the finger cuff 10. , since these two mean blood pressure values Mn and M substantially match, the continuity of the trend is not impaired.

Furthermore, in this embodiment, blood pressure measurement using the finger cuff 10 and the arm cuff 12 is performed using a common pressure sensor 1.
8. Since the electric pump 20, the exhaust valve device 22, etc. are used to measure blood pressure, the measurement of blood pressure values due to instrumental differences between them is easier than when blood pressure measurements are performed using separate devices. Errors are eliminated and blood pressure measurement can be performed with high accuracy.

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

For example, in the embodiment described above, the blood pressure measurement at the finger and the blood pressure measurement at the upper arm are performed five times each, and the correction value ΔK is calculated from the average Mf' and Mn' of the blood pressure values. It is also possible to obtain the correction value using other methods, such as measuring the blood pressure once at a time and using the difference between the two blood pressure values as the correction value.

Furthermore, although the continuous blood pressure measuring device that measures the mean blood pressure value M has been described in the above embodiment, the continuous blood pressure measuring device that measures the systolic blood pressure value, the diastolic blood pressure value, or the mean blood pressure value, the systolic blood pressure value, and the diastolic blood pressure value may also be used. The present invention can be similarly applied. In that case, a correction value for the systolic blood pressure value and a correction value for the diastolic blood pressure value may be calculated separately, and each blood pressure value may be determined using the obtained correction values.

Furthermore, in the embodiment described above, the initially calculated correction value ΔK is used as it is in subsequent continuous blood pressure measurements, but the correction value ΔK may be recalculated at regular time intervals. .

Further, in the embodiment, blood pressure measurement using the finger cuff 10 and the arm cuff 12 is performed using a common pressure sensor 18,
This is performed using an electric pump 20, an exhaust valve device 22, etc., but a finger cuff 10, an arm cuff 1, etc.
It is also possible to configure a configuration in which a separate pressure sensor or the like is provided for each of the two. In that case, by wrapping the cuffs 10 and 12 on the left and right hands,
It is also possible to measure blood pressure on the finger and on the upper arm at the same time.

Further, in the embodiment described above, continuous blood pressure measurement at both the upper arm and the finger can be carried out by operating the changeover switch 34. However, following step S2 in FIG.
8, the configuration may be such that only continuous blood pressure measurement at the finger is performed.

Furthermore, in the above embodiment, the blood pressure value is measured using an oscillometric method during the process of decreasing the cuff pressure, but other blood pressure measurement methods such as an ultrasound method may be adopted, or the blood pressure value may be measured during the process of increasing the cuff pressure. It is also possible to measure the

Although no other examples are given, the present invention can be implemented with various modifications and improvements based on the knowledge of those skilled in the art without departing from the spirit thereof.

[Brief explanation of the drawing]

FIG. 1 is a block diagram illustrating the configuration of a continuous blood pressure measuring device that is an embodiment of the present invention. Second
This figure is a flowchart explaining the operation of the continuous blood pressure measuring device of FIG. 1. FIG. 3 is a flowchart illustrating the correction value ΔK determination routine at step S9 in FIG. FIG. 4 is a diagram showing the claims of the present invention. 10...Finger cuff, 12...Arm cuff (upper arm cuff), 14...Switching valve, 18...Pressure sensor, 3
6...CPU, 38...RAM, 40...ROM,
{Step S4, Step S11, Step R2,
Step R3} (blood pressure value determining means), Step S9
(switching control means), step R6 (correction value calculation means), step S12 (finger blood pressure value correction means).

Claims (1)

[Claims for Utility Model Registration] A finger cuff that presses a finger of a living person, a pressure sensor that detects the pressure within the finger cuff, and a blood pressure value determining means that determines a blood pressure value based on an output signal from the pressure sensor. A continuous blood pressure measurement device for continuously measuring the blood pressure value at the finger, comprising: an upper arm cuff that presses the upper arm of the living body; and a pressure sensor that connects the finger cuff and the upper arm cuff to the upper arm cuff. a switching valve that is alternatively continuous with the finger; and prior to continuous measurement of the blood pressure value on the finger, the switching valve communicates with the finger cuff and the pressure sensor to cause the blood pressure value determining means to measure the blood pressure value on the finger. Switching to two positions: a first blood pressure measurement position where the blood pressure value is determined, and a second blood pressure measurement position where the upper arm cuff and the pressure sensor are communicated and the blood pressure value determining means determines the blood pressure value in the upper arm. a switching control means; calculating a correction value for correcting the blood pressure value at the finger so that the blood pressure value at the finger matches the blood pressure value at the upper arm based on the blood pressure value at the finger and the blood pressure value at the upper arm; and a finger blood pressure value correction means that corrects the continuously measured blood pressure value at the finger based on the correction value calculated by the correction value calculation means. Continuous blood pressure measurement device.