Biological information measurement device

Abstract

To make it easy to visually recognize variation in a pulse interval without regard to an individual difference of the pulse interval by optimizing the resolution of a display area indicating the pulse interval, in a measurement apparatus capable of detecting pulses.SOLUTION: A biological information measurement device comprises: pulse acquisition means which detects a user's pulse; pulse interval calculation means which calculates a pulse interval between one beat and the beat just prior to the beat based on the pulse; display means which displays a level indicator visually indicating the pulse interval; and a display resolution determination unit which uses information of the pulse interval to determine the minimum value and the maximum value of the pulse interval indicated by the level indicator.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a biological information measuring device that measures the pulse of a living body, and more particularly to a biological information measuring device that provides information regarding the interval between measured pulses. [Background technology]

[0002] In recent years, health management has become common by measuring information about an individual's body and health, such as blood pressure, with measuring devices and recording and analyzing the measurement results. In particular, arrhythmias such as atrial fibrillation (AF) can lead to cerebrovascular and cardiovascular diseases, so it is effective to detect fluctuations in pulse intervals with devices such as those mentioned above and notify the user so that he or she can easily recognize them.

[0003] It has been known for some time that such information on pulse intervals can be provided based on biological information acquired when measuring blood pressure using a blood pressure monitor, and for example, Patent Document 1 discloses a blood pressure monitor that can store the pulse wave used to measure blood pressure values ​​and display a pulse wave graph simultaneously with the blood pressure value. It also discloses that a heart mark displayed on the screen flashes in time with the pulse while the blood pressure value is being calculated.

[0004] According to the blood pressure monitor described in Patent Document 1, the user can recognize the pulse interval by checking the blinking interval of the heart mark that blinks in time with the pulse during blood pressure measurement. In addition, since a time series graph of the pulse wave signal level is displayed afterwards as a time series pulse wave graph, the pulse interval (and its fluctuation) can also be confirmed by reading such a graph. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2007-98003 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, as in the technology described in Patent Document 1, it is difficult to recognize the fluctuation in the pulse interval if the mark only blinks in time with the heartbeat, and there is a problem that important fluctuations in the pulse interval may be overlooked. To address this, it is conceivable to make it easier to recognize the fluctuation in the pulse interval by displaying the pulse interval for each beat using a level indicator such as a so-called bar graph meter, rather than blinking the mark.

[0007] Incidentally, pulse intervals vary greatly from person to person, and the size and average value of the intervals vary from person to person. For example, a typical blood pressure monitor measures pulse rates in the range of 40 beats / min to 180 beats / min, and the average pulse interval is 1.5 seconds for a user with a pulse rate of 40 beats / min, and 0.3 seconds for a user with a pulse rate of 180 beats / min.

[0008] Therefore, in order to display the fluctuation of the pulse interval during measurement in real time using the level indicator as described above, it is necessary to set the maximum value of the level indicator so that it can display the maximum expected pulse interval (for example, 1.5 seconds).However, this causes a problem in that for users with a short pulse interval (i.e., a high pulse rate), the display resolution of the level indicator becomes low, making it difficult to recognize the fluctuation of the pulse interval.

[0009] In view of the above circumstances, the present invention provides a measuring device capable of detecting a pulse, which indicates a pulse interval. The present invention aims to provide a technology that optimizes the resolution of a display area and makes it easier to visually recognize fluctuations in pulse intervals regardless of individual differences in pulse intervals. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention employs the following configuration. A pulse acquisition means for detecting a pulse of a user; a pulse interval calculation means for calculating a pulse interval between a pulse and a pulse immediately before the pulse based on the pulse; a display means for displaying a level indicator visually showing the pulse interval; a display resolution determination unit that determines a minimum value and a maximum value of the pulse interval indicated by the level indicator using the information of the pulse interval; The biological information measuring device has the following features.

[0011] The level indicator referred to here may be one that indicates a predetermined feature amount by a non-numerical display (such as the size of a display area), and there is no limitation on its shape or display mode. For example, the level indicator may be one that visually indicates the pulse interval or the amount of change by at least one of the length, area, angle, and number of an area in which the display is activated on the display means.

[0012] With this configuration, the maximum and minimum values ​​of the pulse interval displayed on the level indicator can be optimized for each user, making it possible to easily visually recognize fluctuations in the pulse interval regardless of individual differences in the pulse interval.

[0013] The display resolution determination unit may determine a value obtained by multiplying the maximum value of the consecutive pulse intervals calculated by a predetermined first ratio as the maximum value of the pulse interval indicated by the level indicator. With this configuration, a value obtained by providing a predetermined margin from the maximum pulse wave interval actually measured for the user can be set as the maximum value in the level indicator, so that the resolution of the level indicator can be determined based on the maximum value optimized for the user.

[0014] The display resolution determination unit may determine a value obtained by multiplying the minimum value of the consecutive pulse intervals calculated by a predetermined second ratio as the minimum value of the pulse interval indicated by the level indicator. With this configuration, a value obtained by providing a predetermined margin from the minimum pulse wave interval actually measured for the user can be set as the minimum value of the level indicator, so that the resolution of the level indicator can be optimized for the user based on the minimum and maximum values ​​optimized for the user.

[0015] In addition, the display resolution determination unit may calculate an average value of the consecutive pulse intervals, determine a value obtained by multiplying a maximum positive deviation from the average value by a third ratio as the maximum pulse interval indicated by the level indicator, and determine a value obtained by multiplying a maximum negative deviation from the average value by a fourth ratio as the minimum pulse interval indicated by the level indicator.

[0016] With this configuration, the resolution of the level indicator can be optimized for the user by setting the minimum and maximum values ​​of the level indicator to values ​​that provide a predetermined margin for the maximum positive and negative deviations from the average value of the actually measured pulse wave interval. Furthermore, by changing the third and fourth ratios so that the average value becomes the median value of the level indicator, rather than setting the third and fourth ratios to fixed values, it is possible to realize a more visible level indicator display.

[0017] In addition, the pulse acquisition means may include a cuff and a pressure sensor, and detect the pulse by pressurizing the user's blood vessel with the cuff and detecting a pressure pulse wave of the blood vessel with the pressure sensor, and the display resolution determination unit may determine the minimum and maximum values ​​of the pulse intervals indicated by the level indicator using information on a plurality of the pulse wave intervals calculated from the start of pressurization of the blood vessel until a first predetermined condition is satisfied.

[0018] Here, the first predetermined condition may be, for example, a predetermined time (e.g., 5 seconds) having elapsed since the start of pressurization of the blood vessel with the cuff, or the cuff pressure reaching a predetermined pressure (e.g., 40 mHg), etc. With this configuration, in either pressurized or depressurized measurement, information on a plurality of consecutive pulse wave intervals for determining the maximum and minimum values ​​of the level indicator can be obtained without performing a separate measurement.

[0019] The device may further include a memory means for storing information on the detected pulse interval, the pulse acquisition means including a cuff and a pressure sensor, and detecting the pulse by pressurizing the user's blood vessel with the cuff and detecting a pressure pulse wave in the blood vessel with the pressure sensor, and the display resolution determination unit may determine the minimum and maximum values ​​of the pulse interval indicated by the level indicator using the information on the pulse interval that satisfies a second predetermined condition stored in the memory means.

[0020] Here, the second predetermined condition may be, for example, all pulse intervals calculated during the most recent biological information measurement, etc. With this configuration, the minimum and maximum values ​​of the pulse intervals indicated by the level indicator can be determined with high accuracy using a sufficient amount of information on the user's own pulse intervals.

[0021] In addition, the pulse acquisition means may include a cuff and a pressure sensor, and detect the pulse by pressurizing the user's blood vessel with the cuff and detecting a pressure pulse wave in the blood vessel with the pressure sensor, and the display resolution determination unit may determine the minimum and maximum values ​​of the pulse intervals indicated by the level indicator using information on a plurality of consecutive pulse intervals calculated until the fluid supplied to the cuff is discharged.

[0022] With this configuration, when performing a decompression measurement, a sufficient amount of information on the user's own pulse interval obtained during the pressurization stage can be used to accurately determine the minimum and maximum pulse intervals indicated by the level indicator.

[0023] The level indicator may be configured with a plurality of display segments, and the pulse interval may be expressed by the number of display segments that are activated.

[0024] Note that "activating the display" here refers to a display state in an area where the display state / non-display state can be switched (i.e., deactivating the display refers to a non-display state). For example, if the display means is an LCD, this corresponds to a display being output to the display area on the display, and if the display means is an LED light or the like, this corresponds to the light being turned on. Also, a display segment refers to a unit of the display area where the display can be individually switched between activated and deactivated, and its shape is not particularly limited.

[0025] The above configurations and processes can be combined with each other to constitute the present invention as long as no technical contradiction occurs. In the above, the first to fourth ratios may be different values ​​or may be the same value. Effect of the Invention

[0026] According to the present invention, it is possible to provide a technology that optimizes the resolution of the display area showing the pulse interval in a measuring device capable of detecting pulse, making it easier to visually recognize fluctuations in the pulse interval regardless of individual differences in the pulse interval. [Brief description of the drawings]

[0027] [Figure 1] FIG. 1 is a schematic diagram illustrating an outline of the device configuration and the functional configuration of a blood pressure measurement device according to a first embodiment. [Diagram 2] Fig. 2A is a first diagram showing an example of a level indicator displayed on the image display means of the blood pressure measurement device according to Example 1. Fig. 2B is a second diagram showing an example of a level indicator displayed on the image display means of the blood pressure measurement device according to Example 1. Fig. 2C is a third diagram showing an example of a level indicator displayed on the image display means of the blood pressure measurement device according to Example 1. [Diagram 3] FIG. 3 is an explanatory diagram illustrating a pulse wave signal and a pulse wave interval detected during blood pressure measurement. [Figure 4] FIG. 4 is a graph illustrating an example of the variation in pulse intervals between a patient with sinus rhythm and a patient with atrial fibrillation. [Diagram 5] FIG. 5 is an explanatory diagram illustrating the display resolution of the level indicator of the blood pressure measurement device according to the embodiment. [Figure 6] FIG. 6 is a flowchart illustrating an example of a process performed in the blood pressure measurement device according to the embodiment. [Figure 7] FIG. 7 is a flowchart showing a flow of processing performed in the third modified example of the first embodiment. [Figure 8] FIG. 8 is a flowchart showing a flow of a process performed in the fourth modified example of the first embodiment. [Figure 9] FIG. 9 is a flowchart showing a flow of a process performed in the fifth modified example of the first embodiment. [Figure 10] FIG. 10 is a flowchart showing a flow of processing performed in the sixth modified example of the first embodiment. [Figure 11] Fig. 11A is a first diagram showing variations of a level indicator displayed on an image display means of a blood pressure measuring device according to an embodiment, Fig. 11B is a second diagram showing variations of a level indicator displayed on an image display means of a blood pressure measuring device according to an embodiment, and Fig. 11C is a third diagram showing variations of a level indicator displayed on an image display means of a blood pressure measuring device according to an embodiment. [Figure 12] Fig. 12A is a fourth diagram showing variations of a level indicator displayed on an image display means of a blood pressure measuring device according to an embodiment, Fig. 12B is a fifth diagram showing variations of a level indicator displayed on an image display means of a blood pressure measuring device according to an embodiment, and Fig. 12C is a sixth diagram showing variations of a level indicator displayed on an image display means of a blood pressure measuring device according to an embodiment. [Figure 13]Fig. 13A is a seventh diagram showing variations of a level indicator displayed on the image display means of a blood pressure measuring device according to an embodiment. Fig. 13B is an eighth diagram showing variations of a level indicator displayed on the image display means of a blood pressure measuring device according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] <Example 1> Specific examples of the present invention will be described below with reference to the drawings. However, the material, shape, relative arrangement, and so forth of each component described in the examples are not intended to limit the scope of the present invention unless otherwise specified.

[0029] The present invention can be applied to, for example, a blood pressure measuring device 1 as shown in FIG. 1 is a schematic diagram showing an outline of the device configuration and functional configuration of a blood pressure measuring device 1 in the present embodiment. As shown in Fig. 1, the blood pressure measuring device 1 is generally composed of a main body unit 11, a cuff unit 12, and an air tube 13. Moreover, as shown by the functional blocks in Fig. 1, the blood pressure measuring device 1 includes each of functional units, such as a control unit 100, a sensor unit 110, a cuff pressure control unit 120, a storage unit 130, an operation unit 140, and an image display unit 150.

[0030] The main body 11 has image display means 151 such as a liquid crystal display (LCD) and various operation buttons 141, as well as audio output means such as a speaker, a power source such as a battery, a pump and valve communicating with the cuff, and a housing for accommodating these, all of which are not shown. The cuff 12 is a member that is used by being wrapped around the upper arm of a user, and includes an air bag (cuff) communicating with the pump and valve of the main body 11 via an air tube 13, a belt incorporating the cuff, and a pressure sensor provided on the belt (none of which are shown). In addition, when blood pressure measurement is performed by the Korotkoff method, a microphone may be included.

[0031] The belt of the cuff portion 12 is provided with a fastening means (e.g., a hook-and-loop fastener) for fastening the cuff portion 12 to the user's upper arm, and when measuring blood pressure using the blood pressure measuring device 1, the cuff portion 12 is wrapped around the user's upper arm with the belt.

[0032] The control unit 100 is a means for controlling the blood pressure measurement device 1, and is configured to include, for example, a CPU (Central Processing Unit) and the like. When the control unit 100 accepts a user's operation via the operation unit 140, it controls each component of the blood pressure measurement device 1 to execute various processes, such as blood pressure measurement and presentation of various information, according to a predetermined program. The predetermined program is stored in a storage unit 130 described later and is read out from there. The control unit 100 also includes, as functional modules, a blood pressure value calculation unit 101, a pulse interval calculation unit 102, a display resolution determination unit 103, and a level indicator (LI) display content determination unit 104. These functional modules will be described in detail later.

[0033] The sensor unit 110 includes a pressure sensor (e.g., a piezoresistance sensor having a piezoelectric element) provided in the cuff unit 12 as described above, and detects at least the pulse wave of the user. The sensor unit 110 may include a sensor other than a pressure sensor, and may include a PPG (Photoplethysmography) sensor when detecting the pulse wave by a photoelectric method. The blood pressure measuring device 1 according to this embodiment acquires the pulse of the user based on the pulse wave detected by the sensor unit 110. That is, in this embodiment, the cuff in the cuff unit 12 and the sensor unit 110 (including the pressure sensor) correspond to the pulse acquisition means.

[0034] The cuff pressure control unit 120 controls the pump and valve of the main body unit 11 to adjust the cuff pressure of the cuff unit 12 during blood pressure measurement. Specifically, during blood pressure measurement, the pump is driven with the cuff unit 12 wrapped around the upper arm to send air into the cuff and inflate the cuff (to increase the cuff pressure). In this way, the blood vessels in the user's upper arm are compressed to temporarily inhibit blood flow, and then the pump is stopped, the valve is opened, and air is gradually released from the cuff to deflate the cuff (to decrease the cuff pressure). Hereinafter, the stage of increasing the cuff pressure is also referred to as the cuff inflation stage, and the stage of decreasing the cuff pressure is also referred to as the cuff deflation stage.

[0035] The storage unit 130 is configured to include a main storage device such as a RAM (Random Access Memory) or a ROM (Read Only Memory), and an auxiliary storage device such as a HDD or a flash memory, and stores various information such as application programs, various measurement results such as blood pressure values, pulse rate, pulse waves for each beat, and pulse intervals, and other acquired biological information. The measured blood pressure values, pulse rate, etc. are stored in the storage unit 130 in association with time information such as the time of acquisition and the time of measurement. The time information is, for example, an RTC The auxiliary storage device may be configured to be detachable from the main body 11.

[0036] The operation unit 140 includes various operation buttons 141 (for example, a power button, a measurement execution button, a selection / determination button, etc.), and serves to accept input operations from a user and cause the control unit 100 to execute processing in accordance with the operation.

[0037] The image display unit 150 includes the image display means 151 of the main body 11, and provides information to the user by displaying various information on the image display means 151, such as the measured blood pressure value, the current time, and information related to the wearing state of the cuff. An example of the display content of the image display means 151 is shown in Figs. 2A to 2C. As shown in Figs. 2A to 2C, the image display means 151 has an area for displaying a level indicator LI1 that shows information about the pulse wave interval, which will be described later. The level indicator LI1 will be described in more detail later.

[0038] Each functional module of the control unit 100 will be described below. The blood pressure value calculation unit 101 calculates the user's blood pressure value (and pulse rate) based on the pulse wave acquired by the sensor unit 110. The blood pressure calculation method can use any known technology, for example, the oscillometric method of measuring blood pressure by detecting a pressure pulse wave with a pressure sensor. Alternatively, a microphone may be provided in the cuff unit 12, and the Korotkoff method of detecting Korotkoff sounds may be used. The blood pressure value and pulse rate calculated by the blood pressure value calculation unit 101 may be stored in the storage unit 130 in association with the time of blood pressure measurement.

[0039] The pulse interval calculation unit 102 also calculates the time interval between the peaks of the pulse wave for each beat from the waveform of the pulse wave acquired by the sensor unit 110 (for example, a pressure pulse wave acquired by a pressure sensor). The calculation of the pulse interval will be described with reference to FIG. 3. FIG. 3 is an explanatory diagram showing a schematic relationship between the pulse wave signal and time. In FIG. 3, the time at which a certain wave peak is detected is defined as t 0 Let t be the time when the next wave peak is detected. 1 Then, the interval between one wave and the next is t 1 -t 0 =T 1 In this way, the pulse interval calculation unit 102 calculates t x -t x-1 =T x is calculated as the pulse interval.

[0040] The display resolution determination unit 103 determines the minimum and maximum values ​​of the pulse interval to be displayed on the level indicator LI1, using the information on the pulse interval calculated by the pulse interval calculation unit 102. Here, the display contents of the level indicator LI1 will be described with reference to Figs. 2A to 2C. The level indicator LI1 according to this embodiment has a plurality of display segments S that can be switched between display and non-display, and can indicate the size of the pulse interval calculated by the pulse interval calculation unit 102 depending on the number of display segments S that are in an activated display state (a state in which they are displayed, not hidden).

[0041] In this embodiment, the level indicator LI1 has ten display segments S, and a level indicator display content determination unit 104, which will be described later, determines how many of the ten display segments S to activate. By displaying this on the level indicator LI1, the length of the pulse interval can be visually indicated.

[0042] Incidentally, pulse intervals vary greatly from person to person, with the size and average value of the intervals differing from person to person. Furthermore, as shown in FIG. 4, atrial fibrillation patients have a greater variation in pulse intervals than those in sinus rhythm (healthy individuals). FIG. 4 is a graph showing an example of variation in pulse intervals between those in sinus rhythm and those in atrial fibrillation, with the horizontal axis (X-axis) representing the pulse rate from the start of measurement and the vertical axis (Y-axis) representing variation in pulse intervals. The variation in pulse intervals is shown as a ratio (%) to the average pulse interval. In the graph shown in FIG. 4, the variation in pulse intervals is less than 10% in those in sinus rhythm, but reaches approximately 80% in those with atrial fibrillation.

[0043] For this reason, when the upper and lower limits of the pulse interval displayed by the level indicator LI1 are set as predetermined fixed values, the range of the upper and lower limits must be made large, and this results in insufficient display resolution for users with a high pulse rate (i.e., users with short pulse intervals). For example, taking into account the variation in pulse intervals of patients with atrial fibrillation, if the upper and lower limits of the pulse interval displayed by the level indicator LI1 are set to ±100% of the average pulse interval and the average pulse interval is estimated to be 1.5 seconds (i.e., large) based on the minimum pulse rate of 40 beats / m that can be measured by a general blood pressure monitor, the pulse interval indicated by one display segment S will be 0.3 seconds. In other words, the upper and lower limits of the pulse interval displayed by the level indicator LI1 are (0.3 seconds to 3 seconds).

[0044] However, the upper and lower limit values ​​assumed for a user with a low pulse rate as described above cannot adequately represent the pulse interval of a user with a high pulse rate (for example, 180 beats / m, average pulse interval 0.3 seconds). Figure 5 shows a comparison between the display showing the average pulse interval for a user with a pulse rate of 40 beats / m and the display showing the average pulse interval for a user with a pulse rate of 180 beats / m when the number of display segments is 10 and the upper and lower limits of the pulse interval displayed on the level indicator LI1 are set to 0.3 to 3 seconds.

[0045] In this regard, the display resolution determination unit 103 according to this embodiment uses information on the pulse wave interval actually measured for each user to determine the minimum and maximum values ​​of the pulse interval displayed on the level indicator LI1. This makes it possible to dynamically set the display resolution of the level indicator LI1, and to display the fluctuation of the pulse interval with good visibility regardless of the pulse rate of the user. A specific method for determining the minimum and maximum values ​​of the pulse interval will be described later.

[0046] The level indicator display content determination unit 104 determines the display content of the level indicator LI1 to be displayed on the image display means 151. Specifically, the level indicator display content determination unit 104 determines the display content of the level indicator LI1 to be displayed on the image display means 151.x The number of display segments S to be activated is determined based on the above, and the display content of the level indicator LI1 is determined for each beat.

[0047] Here, a specific example will be described in which the level indicator display content determination unit 104 determines the number of display segments S to be activated. The level indicator display content determination unit 104 determines the minimum pulse interval T min , the maximum value is T max , the maximum number of display segments S is N max The number of display segments S according to the calculated pulse interval is N x is calculated using the following formulas (1) and (2).

[0048]

number

number

[0049] That is, N x (T x -T min ) / Δt+1. x By displaying the display segments S on the level indicator LI1 one beat at a time, the fluctuation of the pulse interval can be indicated. Specifically, when the number of display segments S that are activated is large, the display activation area of ​​the level indicator LI1 becomes large, and conversely, when the number of display segments S that are activated is small, the level indicator LI1 In other words, the larger (longer) the pulse interval is, the larger the display activation area of ​​the level indicator LI1 is, and the smaller (shorter) the pulse interval is, the smaller the display activation area of ​​the level indicator LI1 is. Therefore, by looking at the display, the user can intuitively grasp the variation in the size of the display activation area, and thereby recognize the amount of change in the pulse interval for each beat.

[0050] The display segments S displayed on the level indicator LI1 can indicate the amount of change in the pulse interval in a more easily understandable manner to the user by devising a display mode. For example, as shown in Figures 2A to 2C, in a mode in which the display segments S are arranged in a straight line extending in the left-right direction, activation of the display segments S is performed starting from the first one on the left end to the Nth one. x The number of items displayed is increased by one on the right side until the number is N. x After reaching this number, the display mode can be such that the items are successively made non-displayable from the right side.

[0051] 2A to 2C show an example of the transition of the display of such a display segment S. FIG. x As an indication of x In this example, the level indicator LI1 is N max = 10. In other words, while there are 10 display segments S in the level indicator LI1 as a whole, 9 display segments S are displayed (activated) left-justified.

[0052] FIG. 2B also shows a state in which the display segments S are successively hidden from the right side. As shown in FIG. 2B, when the display segments S are successively hidden, x By leaving the ninth (in this case, the ninth) display segment S active, it is possible to easily recognize the fluctuation of the pulse interval by the change in the position of the remaining display segment S. However, this is not necessarily required, and N x The display segments S may all be simultaneously activated and all remain displayed until the next pulse interval is obtained.

[0053] Then, the next pulse wave peak is detected, and the pulse interval T X+1When the display content of is determined by the level indicator display content determination unit 104, the level indicator LI1 displays a state in which six display segments S are activated, as shown in Fig. 2C. In this embodiment, the display of the level indicator LI1 changes in synchronization with the detected pulse waveform. That is, if the pulse interval is short, the timing at which the display of the level indicator LI1 changes will be earlier, and if the pulse interval is long, the timing at which the display changes will be later. However, the timing at which the display of the level indicator LI1 changes does not necessarily need to be synchronized with the pulse wave, and the timing related to the start and end of the display showing the pulse interval for each beat can be set appropriately.

[0054] Next, a process flow when blood pressure measurement is performed by the blood pressure measurement device 1 according to this embodiment and the fluctuation of the pulse interval of the user during blood pressure measurement is displayed by the level indicator LI1 will be described with reference to Fig. 6. Fig. 6 is a flowchart showing part of the process flow when blood pressure measurement is performed by the blood pressure measurement device 1 according to this embodiment.

[0055] As shown in Fig. 6, when a user operates to start blood pressure measurement, the sensor unit 110 initializes the pressure sensor (S101). Then, the cuff pressure control unit 120 closes the valve (S102) and drives the pump (S103) to send air into the cuff and inflate it. After that, the control unit 100 judges whether the current time is a predetermined initial pressurization period (S104). Whether the current time is a predetermined initial pressurization period can be judged based on conditions such as whether a predetermined time (e.g., 5 seconds) has elapsed since the start of the measurement operation and whether the cuff pressure has reached a predetermined value (e.g., 40 mHg).

[0056] When it is determined in step S104 that the pressurization is in the initial stage, the pulse interval calculation unit 102 The information on the pulse interval calculated by the pulse rate sensor 130 is acquired (S105). Specifically, for example, the information on the pulse interval calculated for each beat is stored in the storage unit 130. After the process of step S105 is executed, the process proceeds to step S106, where it is determined whether the cuff pressure has reached a predetermined pressure (for example, 200 mHg) (S106). On the other hand, if it is determined in step S104 that the cuff pressure is not at the initial pressurization stage, the process proceeds directly to step S106.

[0057] If it is determined in step S106 that the cuff pressure has not reached the predetermined pressure, the process returns to step S103 and repeats the subsequent processes. On the other hand, if it is determined in step S106 that the cuff pressure has reached the predetermined pressure, the cuff pressure control unit 120 stops the pump (S107).

[0058] Then, the display resolution determination unit 103 determines the maximum and minimum values ​​of the pulse interval displayed on the level indicator LI1 based on the information of the consecutive pulse intervals acquired in S105. That is, the display resolution of the level indicator LI1 is determined (S108). Specifically, for example, a value obtained by multiplying the minimum value of the consecutive pulse intervals acquired by a preset ratio (e.g., 90%) can be determined as the minimum value of the pulse interval indicated by the level indicator LI1. Also, a value obtained by multiplying the maximum value of the consecutive pulse intervals acquired by a preset ratio (e.g., 110%) can be determined as the maximum value of the pulse interval indicated by the level indicator LI1. The display resolution determined in this way is determined based on the actually acquired pulse interval of the user, and is therefore optimized for that user.

[0059] Following the process of step S108, the cuff pressure control unit 120 gradually opens the valve to deflate the cuff (S109). The pulse interval calculation unit 102 then calculates the pulse interval for each beat from the pulse wave acquired during this time (S110), and based on this, the level indicator display content determination unit 104 determines the number of display segments S to be activated for each beat. The image display unit 150 then displays the determined content on the level indicator LI1 (S111), allowing the user to easily visually recognize the fluctuation in the pulse interval for each beat during blood pressure measurement.

[0060] During the process of contracting the cuff, the blood pressure value calculation unit 101 measures the blood pressure values ​​(systolic blood pressure and diastolic blood pressure), and in step S112, the blood pressure value calculation unit 101 determines whether the blood pressure value calculation has been completed (S112). If it is determined that the blood pressure value calculation has not been completed, the process returns to step S110 and the subsequent processes are repeated. On the other hand, if it is determined in step S112 that the blood pressure value calculation has been completed, the cuff pressure control unit 120 opens the valve to rapidly vent the cuff and contract the cuff (S113). After that, the image display unit 150 displays the measured value (which may include the pulse rate in addition to the blood pressure value) (S114), and the series of processes is terminated. The measured values ​​may be stored in the storage unit 130.

[0061] According to the blood pressure measuring device 1 configured as above, the user can intuitively recognize the fluctuation of the pulse interval during blood pressure measurement, and can more easily recognize the pulsation of the pulse. As a result, if there is an abnormality such as arrhythmia, the abnormality of the pulse can be easily grasped from the discomfort, and daily blood pressure measurement can contribute to early detection of cardiovascular disease. Furthermore, since the display resolution determination unit 103 determines the display resolution of the level indicator LI1 to be optimized for the user, the fluctuation of the pulse interval can be displayed with an appropriate resolution regardless of the difference in the pulse interval of each user.

[0062] (Variation 1) In the above embodiment 1, the minimum and maximum values ​​of the consecutive pulse intervals acquired in step S105 are multiplied by a preset ratio to set the minimum and maximum values ​​of the pulse intervals indicated by the level indicator LI1, but this is not necessarily required. Alternatively, such a process may be performed for only one of the maximum and minimum values, and a specified value may be used for the other. For example, the display resolution determination unit 103 may determine a specified value (e.g., 0 seconds) for the minimum value as the minimum value of the pulse interval indicated by the level indicator LI1.

[0063] (Variation 2) Furthermore, the display resolution determination unit 103 may calculate the average value of the consecutive pulse intervals acquired in step S105, and may multiply the maximum positive and negative deviations from the average value among the consecutive pulse intervals acquired by a predetermined ratio (e.g., 110%) to obtain the minimum and maximum values ​​of the pulse intervals indicated by the level indicator LI1. The predetermined ratios to be multiplied may be different for the maximum positive deviation and the maximum negative deviation. Furthermore, instead of setting the ratio to be multiplied by the maximum positive and negative deviations to a fixed value, it is possible to change the ratio to be multiplied by the maximum positive and negative deviations so that the average value becomes the median value of the level indicator, thereby realizing a display of the level indicator with better visibility.

[0064] (Variation 3) In the above-mentioned embodiment 1, the processing in the case where blood pressure measurement is performed by so-called reduced pressure measurement has been described, but the present invention can also be applied to the case where blood pressure measurement is performed by so-called pressurized measurement. An example of the processing in such a case is shown in FIG. 7. Note that the device configuration of the vital information measurement device in this modified example is the same as that of embodiment 1. In addition, in the processing shown in FIG. 7, the same processes as those described in embodiment 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0065] As shown in FIG. 7, in this modification, the processes from step S101 to step S105 are the same as those in the above-mentioned embodiment 1. In this modification, after step S105, the control unit 100 executes a process of determining whether the display resolution has been determined, that is, whether the minimum and maximum values ​​of the pulse interval displayed by the level indicator LI1 have been optimized for the user (S201). If it is determined that the display resolution has not yet been determined, the display resolution determination unit 103 executes a process of determining the display resolution (S108). The method of determining the display resolution may be the same as that in the above-mentioned embodiment 1, or the method described in the above-mentioned modification 1 or 2 may be used.

[0066] Here, in this modified example, blood pressure measurement is performed by the pressurization measurement method, and in addition to the display resolution determination process, the blood pressure value calculation unit 101 executes a process of calculating the blood pressure value. Therefore, when it is determined in step S201 that the display resolution has been determined, and after the display resolution is determined in step S108, the pulse interval calculation unit 102 immediately calculates the pulse interval (S110), and the image display unit 150 executes a process of displaying the calculated pulse interval on the level indicator LI1 for each beat (S111). Thereafter, the blood pressure value calculation unit 101 determines whether or not the blood pressure value calculation has been completed (S112), and if it is determined that the blood pressure value calculation has not been completed, the process returns to step S104 and repeats the subsequent processes. On the other hand, if it is determined in step S112 that the blood pressure value calculation has been completed, the cuff pressure control unit 120 stops the pump (S202), opens the valve, and deflates the cuff (S113). Thereafter, the image display unit 150 displays the measurement value (S114), and the series of processes ends.

[0067] As described above, by determining the display resolution using pulse interval information obtained at the initial stage of blood pressure measurement (more specifically, at the initial stage of cuff pressurization), the display resolution of the level indicator LI1 can be optimized according to the user not only in the case of reduced pressure measurement but also in the case of pressurized measurement, and the fluctuation in the pulse interval for each beat can be displayed.

[0068] (Variation 4) In addition, as long as blood pressure measurement is performed by the reduced pressure measurement method, the following processing flow is also possible. FIG. 8 is a flowchart showing part of the processing flow executed in the blood pressure measurement device 1 in this modified example. As shown in FIG. 8, the processing flow of this modified example is the same as that of the first embodiment except that the processing of step S104 in the first embodiment is not present. That is, in this modified example, during the cuff inflation stage for reduced pressure measurement, pulse intervals are continuously acquired, and the display resolution is determined using information on the acquired continuous pulse intervals, and then the pulse intervals calculated in the cuff deflation stage for blood pressure measurement are displayed on the level indicator LI1 for each beat. This allows a larger amount of data to be used for determining the display resolution than when only information on the pulse intervals acquired in the initial stage of cuff inflation is used, so that the display resolution can be determined more accurately.

[0069] (Variation 5) Next, a fifth modified example of the present invention will be described. The device configuration of the blood pressure measuring device 1 according to this modified example is similar to that of the blood pressure measuring device 1 of the first embodiment, and therefore the same reference numerals as those in the first embodiment will be used and overlapping parts will be omitted. In this modified example, the process relating to the display resolution determination is different from that of the first embodiment, and therefore this point will be mainly described.

[0070] In the blood pressure measuring device 1 according to this modification, information on a series of multiple pulse intervals calculated when blood pressure was measured in the past is stored in the storage unit 130. Note that, hereinafter, information on a series of multiple pulse intervals is also referred to as a "group of pulse interval information."

[0071] Fig. 9 shows a process flow when blood pressure measurement is performed by the blood pressure measurement device 1 according to this modification. As shown in Fig. 9, when a user performs an operation to start blood pressure measurement, the sensor unit 110 initializes the pressure sensor (S301). Next, the display resolution determination unit 103 reads and acquires a group of pulse interval information from the previous blood pressure measurement (i.e., the most recent) stored in the storage unit 130 (S302), and determines the display resolution based on this (S303). Note that the display resolution determination can be performed by the same method as in the above-mentioned embodiment 1 and the above-mentioned modification 1 or 2, and therefore will not be described again.

[0072] Next, the cuff pressure control unit 120 closes the valve (S304) and drives the pump (S305) to send air into the cuff and inflate the cuff. After that, the cuff pressure control unit 120 determines whether the cuff pressure has reached a predetermined pressure (e.g., 200 mHg) (S306). If it is determined that the cuff pressure has not reached the predetermined pressure, the process returns to step S305 and repeats the subsequent processes. On the other hand, if it is determined in step S306 that the cuff pressure has reached the predetermined pressure, the cuff pressure control unit 120 stops the pump (S307).

[0073] Following the process of step S307, the cuff pressure control unit 120 gradually opens the valve to deflate the cuff (S308). The pulse interval calculation unit 102 then calculates the pulse interval for each beat from the pulse wave acquired during this time (S309), and based on this, the level indicator display content determination unit 104 determines the number of display segments S to be activated for each beat. The image display unit 150 then displays the determined content on the level indicator LI1 (S310), allowing the user to easily visually recognize the fluctuation in the pulse interval for each beat during blood pressure measurement.

[0074] During the process of the cuff contracting, the blood pressure value calculation unit 101 measures the blood pressure value, and in step S311, it is determined whether or not the blood pressure value calculation has been completed (S311). If it is determined that the blood pressure value calculation has not been completed, the process returns to step S309 and the subsequent processes are repeated. On the other hand, if it is determined in step S311 that the blood pressure value calculation has been completed, the cuff pressure control unit 120 opens the valve to rapidly vent the cuff and contract the cuff (S312). Thereafter, the image display unit 150 displays the measured value (S313), and then the control unit 100 executes a process of storing the group of pulse interval information calculated this time in the storage unit 130 (S314), and the series of processes ends.

[0075] As described above, in this modified example, the pulse interval information used to determine the display resolution is obtained using a group of pulse interval information stored the previous time blood pressure was measured, so that the display resolution can be set with high accuracy based on sufficient data.

[0076] (Variation 6) In the above modification, the process of measuring blood pressure values ​​by the so-called decompression measurement method has been described, but the display resolution can also be determined by using a group of past pulse interval information when measuring blood pressure by the pressurization measurement method. FIG. 10 shows the flow of the process in such a case. As shown in FIG. 10, in this modification, the blood pressure value is measured during the process of pressurizing the cuff, rather than the decompression method in which the cuff is inflated until the cuff pressure reaches a predetermined pressure and then the blood pressure is measured while gradually decompressing. Therefore, the processes from step S306 to step S308 do not exist. Other than that, the same processes as those in the above modification 4 are performed. In this way, the method of determining the display resolution by using a group of pulse interval information obtained in advance can be suitably used when blood pressure is measured by pressurization measurement.

[0077] <Other> The above-mentioned embodiment is merely an illustrative example of the present invention, and the present invention is not limited to the above-mentioned specific embodiment. Various modifications and combinations of the present invention are possible within the scope of the technical concept of the present invention. For example, in the above-mentioned embodiment, the level indicator LI1 is configured such that the display segments S are arranged in a straight line extending in the left-right direction, but the level indicator can be configured in various ways depending on the shape of the device and the structure of the image display means 151. Figures 11A to C, 12A to C, and 13A to B show the display modes of the level indicator according to such modified examples.

[0078] The shape of the level indicator may be circular instead of linear, as in the level indicator LI2 shown in Fig. 11A. Also, the level indicator may be configured as a vertically extending linear shape, as in the level indicator LI3 shown in Fig. 11B. Furthermore, as shown in Fig. 11C, a level indicator LI4 may be configured in such a manner that a plurality of radially arranged display segments S are activated from the inside to the outside.

[0079] Moreover, the level indicator does not necessarily have to be composed of a plurality of display segments. Examples of level indicators LI5 in such cases are shown in Fig. 12A to C. Fig. 12A shows a pulse interval T x In this variant, the bar B extends from left to right to indicate the x can be calculated as the length (or area) of the display activation region in the displayable region of the entire level indicator LI5, rather than the number of display segments. FIG. 12B shows a state in which the bars are successively made invisible from the right side. In this case, as in the case of the first embodiment, the peak level portion of bar B in FIG. 12A remains activated. FIG. 12C shows a state in which the bar indicating the pulse interval extends from left to right, and the pulse interval T x+1 This shows the state in which the following is displayed.

[0080] Furthermore, the method of expressing the fluctuation of the pulse interval is not limited to the increase or decrease of the display area in the level indicator as described above (the number of display segments that are activated, the length and area of ​​the bar). Such a display mode of the level indicator is shown in Fig. 13A and Fig. 13B. The level indicator shown in Fig. 13A and Fig. 13B has a shape that includes a part of the circumference (arc) and a needle that extends from the inside of the arc toward the arc, and has a configuration similar to that of a so-called analog meter. It is.

[0081] 13A is a diagram showing a modified example of the first embodiment showing the pulse interval for each beat, and the needle of the level indicator LI6 is displayed so as to point to any position between min and max on the circumference corresponding to the pulse interval for each beat. That is, the angle of the needle changes for each beat according to the pulse interval.

[0082] 13B shows an example of a level indicator LI7 that indicates a position on an arc corresponding to the deviation from the average value calculated using information on a group of pulse intervals for each beat. Specifically, the level indicator LI7 uses a reference line K indicating the average value calculated using information on a group of pulse intervals located at the center of the arc as a standard position, and displays the pointer swinging to the right from the reference line K by the deviation when the latest calculated pulse interval is a value that is a positive deviation from the average value. On the other hand, when the latest calculated pulse interval is a value that is a negative deviation from the average value, the pointer swings to the left from the reference line K by the deviation. Note that when the latest calculated pulse interval is equivalent to the average value (within the same range according to the resolution), the pointer does not swing to the left or right from the reference line K, but a special display such as blinking the pointer may be used to make it easier to recognize that the pulse interval is equivalent to the average value.

[0083] In addition, in the above embodiments, the level indicator is displayed on an LCD, but instead, the display segment can be configured with a number of LED indicator lights. In this case, the lighting of the LED indicator lights corresponds to the activation of the display segment.

[0084] In addition, in each of the above embodiments, the pressure pulse wave is acquired by a pressure sensor, but the volume pulse wave may be acquired by a PPG sensor. In addition, in each of the above embodiments, the blood pressure measuring device is used as an example, but the present invention is not limited to this and can be applied to other biological information measuring devices (e.g., electrocardiographs, body composition monitors, etc.) as long as they are equipped with a sensor capable of acquiring a pulse. [Explanation of symbols]

[0085] 1. Blood pressure measuring device 11 Main body 12 Cuff section 13. Air tube 151...Image display means 100, 200...Control section 110 Sensor section 120 Cuff pressure control system 130...Storage section 140...Operation unit 150 Image display unit LI1, LI2, LI3, LI4, LI5, LI6, LI7...Level indicators S Display Segment B···Bar K...Reference line

Claims

1. a pulse acquisition means for detecting the pulse of a user; a pulse interval calculation means for calculating a pulse interval between a pulse and the pulse immediately before the pulse based on the pulse; a display means for displaying a level indicator visually indicating the pulse interval; a display resolution determination unit that determines a minimum value and a maximum value of the pulse interval indicated by the level indicator using the pulse interval information; A biological information measuring device having the above.

2. the display resolution determination unit determines a value obtained by multiplying the calculated maximum value of the consecutive pulse intervals by a predetermined first ratio as the maximum value of the pulse interval indicated by the level indicator; 2. The biological information measuring device according to claim 1, wherein:

3. the display resolution determination unit determines a value obtained by multiplying the minimum value of the calculated consecutive pulse intervals by a predetermined second ratio as the minimum value of the pulse interval indicated by the level indicator; 3. The biological information measuring device according to claim 2, wherein:

4. the display resolution determination unit calculates an average value of the consecutive pulse intervals, determines a value obtained by multiplying a maximum positive deviation from the average value by a third ratio as the maximum value of the pulse interval indicated by the level indicator, and determines a value obtained by multiplying a maximum negative deviation from the average value by a fourth ratio as the minimum value of the pulse interval indicated by the level indicator.

2. The biological information measuring device according to claim 1, wherein:

5. the pulse acquisition means includes a cuff and a pressure sensor, and detects the pulse by pressurizing the blood vessel of the user with the cuff and detecting a pressure pulse wave of the blood vessel with the pressure sensor, the display resolution determination unit determines a minimum value and a maximum value of the pulse interval indicated by the level indicator using information on a plurality of pulse intervals calculated during a period from when pressurization of the blood vessel begins until a first predetermined condition is satisfied.

2. The biological information measuring device according to claim 1, wherein:

6. The device further includes a storage means for storing information on the detected pulse interval, the pulse acquisition means includes a cuff and a pressure sensor, and detects the pulse by pressurizing the blood vessel of the user with the cuff and detecting a pressure pulse wave of the blood vessel with the pressure sensor, the display resolution determination unit determines a minimum value and a maximum value of the pulse interval indicated by the level indicator using information on the pulse interval that satisfies a second predetermined condition stored in the storage means.

2. The biological information measuring device according to claim 1, wherein:

7. the pulse acquisition means includes a cuff and a pressure sensor, and detects the pulse by pressurizing the blood vessel of the user with the cuff and detecting a pressure pulse wave of the blood vessel with the pressure sensor, the display resolution determination unit determines a minimum value and a maximum value of the pulse interval indicated by the level indicator using information on a plurality of consecutive pulse intervals calculated until the fluid supplied to the cuff is discharged.

2. The biological information measuring device according to claim 1, wherein:

8. the level indicator visually indicates the pulse interval by at least one of the length, area, angle, and number of regions whose display is activated on the display means; The biological information measuring device according to claim 1 ,

9. The level indicator is configured by a plurality of display segments, and the pulse interval is expressed by the number of the display segments that are activated.

9. The biological information measuring device according to claim 8.

Images