Sphygmomanometer, blood pressure calculation method, and storage medium

Abstract

In the present invention, there are a normal blood pressure measurement mode for measuring blood pressure according to a blood pressure measurement instruction and a nighttime blood pressure measurement mode for automatically starting blood pressure measurement according to a predetermined schedule. When the normal blood pressure measurement mode is switched to the nighttime blood pressure measurement mode through the mode operation unit (S11), the algorithm for calculating blood pressure using the oscillometric method is set to be switched from the algorithm for sitting position to the algorithm for supine position (S12). The blood pressure value is calculated using the algorithm currently set for calculating blood pressure using the oscillometric method (S17).

Description

Technical Field

[0001] The present invention relates to a sphygmomanometer, and more specifically, to a sphygmomanometer having a normal blood pressure measurement mode and a nighttime (sleep) blood pressure measurement mode. In addition, the present invention relates to a blood pressure calculation method for calculating blood pressure using such a sphygmomanometer. In addition, the present invention relates to a storage medium storing a program for causing a computer to execute such a blood pressure calculation method. Background Art

[0002] In the past, as a blood pressure monitor of this type, for example, in Patent Document 1 (International Publication No. 2018 / 168797), a blood pressure monitor that switches the measurement posture determination conditions between a normal blood pressure measurement mode and a nighttime blood pressure measurement mode is disclosed, so as to appropriately determine whether the measurement position of the blood pressure monitor is correct for each measurement posture in a sitting position and a supine position.

[0003] In addition, for example, Patent Document 2 (Japanese Patent Application Publication No. 2018-153240) discloses a sphygmomanometer that corrects blood pressure values ​​using height information of the sphygmomanometer measured during a measurement process including sleep.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2018 / 168797

[0007] Patent Document 2: Japanese Patent Application Publication No. 2018-153240 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] Patent Documents 1 and 2 above also disclose the application of these technologies to a wrist blood pressure monitor worn on the wrist (forearm). However, since the wrist blood pressure monitor has a high degree of freedom in position, there is a problem of low stability in the process of accurately measuring or determining the measurement posture during sleep.

[0010] Therefore, the subject of the present invention is to provide a sphygmomanometer that can stably and accurately calculate blood pressure values ​​in a sphygmomanometer having a normal blood pressure measurement mode and a nighttime (sleep) blood pressure measurement mode. In addition, the subject of the present invention is to provide a blood pressure calculation method that can stably and accurately calculate blood pressure using such a sphygmomanometer. In addition, the subject of the present invention is to provide a storage medium storing a program for causing a computer to execute such a blood pressure calculation method.

[0011] Means used to solve problems

[0012] In order to solve the above-mentioned problems, the blood pressure meter of the present invention temporarily compresses the wrist as the measured part by a blood pressure measurement cuff and performs blood pressure measurement by oscillometric measurement, and is characterized in that:

[0013] The sphygmomanometer has:

[0014] A measurement instruction input unit for inputting blood pressure measurement instructions;

[0015] a mode operation unit for inputting an instruction for switching the mode between a normal blood pressure measurement mode for performing blood pressure measurement according to the blood pressure measurement instruction input by the measurement instruction input unit and a nighttime blood pressure measurement mode for automatically starting blood pressure measurement according to a predetermined schedule;

[0016] an algorithm storage unit storing an algorithm for a sitting position and an algorithm for a supine position as algorithms for calculating blood pressure using an oscillometric method;

[0017] a first switching unit configured to switch the algorithm for calculating the blood pressure using the oscillometric method from the sitting position algorithm to the supine position algorithm when the normal blood pressure measurement mode is switched to the nighttime blood pressure measurement mode by the mode operation unit; and

[0018] The blood pressure calculation unit calculates the blood pressure value based on the pressure of the blood pressure measurement cuff when the blood pressure measurement cuff is in the process of pressurization or depressurization, using an algorithm currently set for blood pressure calculation using the oscillometric method.

[0019] In this specification, the "measurement instruction input unit" and "mode operation unit" are, for example, switches provided on the main body of the blood pressure monitor, which can receive instructions from the user to turn on the switch, or can also be composed of a communication unit that receives instructions from a smartphone or the like outside the blood pressure monitor through wireless communication.

[0020] "An algorithm for calculating blood pressure using the oscillometric method" refers to an algorithm that sets an envelope for a sequence of pulse wave amplitudes obtained from the cuff pressure when the blood pressure measuring cuff is in the process of pressurization or depressurization, sets a threshold level of a predetermined ratio (including a threshold level for systole and a threshold level for diastole) for the maximum value of the envelope, and calculates the cuff pressure at the moment when the envelope crosses these threshold levels as the highest blood pressure (systolic blood pressure) and the lowest blood pressure (diastolic blood pressure). The difference between the algorithm for sitting and the algorithm for supine is typically expressed as the difference in the threshold level (for example, the difference in ratio relative to the maximum value of the envelope, or a positive or negative numerical value (offset value) relative to a certain ratio).

[0021] The “currently set algorithm” refers to the algorithm set at the time when the blood pressure calculation unit performs blood pressure calculation.

[0022] In the sphygmomanometer of the present invention, the algorithm storage unit stores an algorithm for sitting and an algorithm for supine as algorithms for calculating blood pressure using the oscillometric method. If the normal blood pressure measurement mode is switched to the nighttime blood pressure measurement mode by the mode operation unit, the first switching unit is set to switch the algorithm for calculating blood pressure using the oscillometric method from the algorithm for sitting to the algorithm for supine. In the nighttime blood pressure measurement mode, blood pressure measurement is automatically started according to a predetermined schedule. That is, according to a predetermined schedule, the measured part is temporarily compressed by the blood pressure measurement cuff. When the blood pressure measurement cuff is in a pressurization process or a decompression process, the blood pressure calculation unit calculates the blood pressure value based on the pressure of the blood pressure measurement cuff, using the algorithm currently set for calculating blood pressure using the oscillometric method (at this moment, the algorithm for supine position). In the nighttime blood pressure measurement mode, it is usually desired that the subject is in a supine position. Therefore, by using the algorithm for the supine position, blood pressure values ​​(maximum blood pressure and minimum blood pressure) can be calculated stably and with high accuracy.

[0023] In addition, since this sphygmomanometer is a type that compresses the wrist as the measured part, it is expected that the degree of interference with the subject's sleep is less than that of the type that compresses the upper wrist (Imai et al., "Development and evaluation of ahome nocturnal blood pressure monitoring system using a wrist-cuff device", Blood Pressure Monitoring 2018, 23, P318-326). Therefore, this sphygmomanometer is suitable for nighttime (sleep) blood pressure measurement.

[0024] In one embodiment of the blood pressure meter, it is characterized by having: a second switching unit, in the nighttime blood pressure measurement mode, when a blood pressure measurement instruction is input in an inserted manner through the measurement instruction input unit, unlike the predetermined schedule, the algorithm used to calculate the blood pressure using the oscillometric measurement method is set to be switched from the algorithm for the supine position to the algorithm for the sitting position, so as to perform a blood pressure measurement corresponding to the inserted blood pressure measurement instruction.

[0025] Even during the period when the sphygmomanometer is in the nighttime blood pressure measurement mode, the user can indicate the blood pressure measurement in an insertion manner by pressing the measurement switch as the measurement instruction input unit provided on the outer surface of the main body integrally provided with the blood pressure measurement cuff, which is different from the predetermined schedule. At this time, it is desirable that the user is in a sitting position rather than a supine position. Therefore, when performing the blood pressure measurement corresponding to the blood pressure measurement instruction, if the blood pressure value is calculated directly using the algorithm for the supine position, the problem of poor measurement accuracy will arise. Therefore, in the sphygmomanometer, in the nighttime blood pressure measurement mode, different from the predetermined schedule, when the blood pressure measurement instruction is input in an insertion manner through the measurement switch as the measurement instruction input unit, the second switching unit is set to switch the algorithm used for blood pressure calculation using the oscillometric method from the algorithm for the supine position to the algorithm for the sitting position, so as to perform the blood pressure measurement corresponding to the inserted blood pressure measurement instruction. In this state, the measured part is temporarily compressed by the blood pressure measurement cuff to perform the blood pressure measurement corresponding to the inserted blood pressure measurement instruction. When the blood pressure measuring cuff is in the process of pressurization or decompression, the blood pressure calculation unit calculates the blood pressure value based on the pressure of the blood pressure measuring cuff using the algorithm currently set for blood pressure calculation using the oscillometric method (the algorithm for sitting position at this moment). Even in the nighttime blood pressure measurement mode, when the blood pressure measurement instruction is input in an inserted manner through the measurement switch serving as the measurement instruction input unit, as described above, it is preferred that the subject be in a sitting position rather than a supine position. Therefore, by using the algorithm for sitting position, blood pressure values ​​(maximum blood pressure and minimum blood pressure) can be calculated stably and with high accuracy. Therefore, according to the sphygmomanometer of this embodiment, in the nighttime blood pressure measurement mode, unlike the predetermined schedule, when performing blood pressure measurement corresponding to the inserted blood pressure measurement instruction, the blood pressure value can be calculated stably and with high accuracy.

[0026] In one embodiment of the blood pressure meter, it is characterized by having: a third switching unit, when the blood pressure measurement corresponding to the inserted blood pressure measurement indication is completed, as long as there is a blood pressure measurement scheduled according to the schedule, the algorithm used to calculate the blood pressure using the oscillometric method is set to switch from the algorithm for the sitting position to the algorithm for the supine position.

[0027] In the sphygmomanometer of this embodiment, when the blood pressure measurement corresponding to the blood pressure measurement instruction is completed, as long as there is a blood pressure measurement scheduled according to the schedule, the third switching unit is set to switch the algorithm used for calculating the blood pressure using the oscillometric method from the algorithm for the sitting position to the algorithm for the supine position. Therefore, after the blood pressure measurement corresponding to the inserted blood pressure measurement instruction is completed, the blood pressure measurement is automatically started according to the schedule. That is, according to the schedule, the measured part is temporarily compressed by the blood pressure measurement cuff. When the blood pressure measurement cuff is in the pressurization process or the decompression process, the blood pressure calculation unit calculates the blood pressure value based on the pressure of the blood pressure measurement cuff, using the algorithm currently set for calculating the blood pressure using the oscillometric method (at this moment, the algorithm for the supine position). In the nighttime blood pressure measurement mode, as described above, it is usually desired that the subject is in the supine position. Therefore, after the blood pressure measurement corresponding to the inserted blood pressure measurement instruction is completed, the blood pressure value (maximum blood pressure and minimum blood pressure) can be stably and accurately calculated by using the algorithm for the supine position.

[0028] In one embodiment of the blood pressure meter, it is characterized by having: a fourth switching unit, which is set to switch the algorithm used for calculating the blood pressure using the oscillometric method from the algorithm for the supine position to the algorithm for the sitting position when all blood pressure measurements specified in the schedule are completed.

[0029] In the sphygmomanometer of this embodiment, when all blood pressure measurements specified in the schedule are completed, the fourth switching unit is set to switch the algorithm for calculating blood pressure using the oscillometric method from the algorithm for the supine position to the algorithm for the sitting position. Therefore, after the nighttime blood pressure measurement mode is ended, for example, when the normal blood pressure measurement mode is started by default, the blood pressure calculation unit can calculate the blood pressure value using the algorithm for the sitting position for calculating blood pressure using the oscillometric method. Therefore, the blood pressure calculation in the normal blood pressure measurement mode can be accurately performed.

[0030] In one embodiment of the sphygmomanometer, it is characterized in that:

[0031] A main body is provided integrally with the blood pressure measuring cuff,

[0032] The measurement instruction input unit and the mode operation unit each include a switch disposed on the outer surface of the main body.

[0033] The main body is equipped with the algorithm storage unit, each switching unit, a pressure control unit that controls the pressure of the blood pressure measurement cuff, and the blood pressure calculation unit.

[0034] Here, the “pressure control unit” includes, for example, a pump that supplies pressurizing fluid to the blood pressure measurement cuff, a valve that discharges fluid from the blood pressure measurement cuff, and a member that drives and controls the pump, valve, and the like.

[0035] The blood pressure monitor of this embodiment can be integrally and compactly configured as a wrist blood pressure monitor, thereby facilitating operation by the user.

[0036] On the other hand, the blood pressure calculation method of the present invention is used for a blood pressure meter that temporarily compresses the wrist as the measured part with a blood pressure measurement cuff and performs blood pressure measurement using an oscillometric method, characterized in that:

[0037] The sphygmomanometer has:

[0038] A measurement instruction input unit for inputting blood pressure measurement instructions;

[0039] a mode operation unit for inputting an instruction for switching the mode between a normal blood pressure measurement mode for performing blood pressure measurement according to a blood pressure measurement instruction input by the measurement instruction input unit and a nighttime blood pressure measurement mode for automatically starting blood pressure measurement according to a predetermined schedule; and

[0040] an algorithm storage unit for storing an algorithm for a sitting position and an algorithm for a supine position as algorithms for calculating blood pressure using an oscillometric method,

[0041] The blood pressure calculation method includes the following processing:

[0042] When the normal blood pressure measurement mode is switched to the nighttime blood pressure measurement mode through the mode operation unit, the algorithm for calculating the blood pressure using the oscillometric method is set to be switched from the algorithm for the sitting position to the algorithm for the supine position.

[0043] When the blood pressure measurement cuff is in the process of pressurizing or depressurizing, a blood pressure value is calculated based on the pressure of the blood pressure measurement cuff using an algorithm currently set for calculating blood pressure using the oscillometric method.

[0044] According to this blood pressure calculation method, in the nighttime blood pressure measurement mode, when blood pressure measurement is performed in response to an inserted blood pressure measurement instruction, unlike a predetermined schedule, the blood pressure value can be stably and accurately calculated.

[0045] Moreover, in yet another aspect, a storage medium of the present invention stores a program for causing a computer to execute the blood pressure calculation method.

[0046] The blood pressure calculation method can be executed by causing a computer to execute the program of the present invention.

[0047] Effects of the Invention

[0048] As can be seen from the above, according to the sphygmomanometer and the blood pressure calculation method of the present invention, in the sphygmomanometer having the normal blood pressure measurement mode and the nighttime (sleep) blood pressure measurement mode, it is possible to stably and accurately calculate the blood pressure value. In addition, according to the program stored in the storage medium of the present invention, it is possible to enable a computer to execute such a blood pressure calculation method. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a diagram showing the appearance of a wrist blood pressure monitor according to one embodiment of the present invention.

[0050] Figure 2 It is a diagram showing the block configuration of a sphygmomanometer.

[0051] Figure 3 The figure shows a mode in which the above-mentioned blood pressure monitor is worn on the left wrist as the measurement site.

[0052] Figure 4A The figure shows the sitting position as the measurement posture.

[0053] Figure 4B The figure shows the supine position as a measurement posture.

[0054] Figure 5 This is a diagram showing the operation flow when the blood pressure measurement is performed by the above-mentioned blood pressure monitor in the normal blood pressure measurement mode.

[0055] Figure 6 This is a diagram showing the operation flow when the blood pressure measurement is performed by the above-mentioned blood pressure monitor in the nighttime blood pressure measurement mode.

[0056] Figure 7 (A) is a graph showing the temporal evolution of the cuff pressure PC accompanying the blood pressure measurement. Figure 7 (B) is a diagram showing the temporal evolution of the pulse wave signal SM accompanying the blood pressure measurement. Figure 7 (C) is a diagram showing an envelope ENV set for the sequence of pulse wave amplitudes formed by the pulse wave signal SM.

[0057] Figure 8 It is a diagram for explaining the method of calculating blood pressure in the nighttime blood pressure measurement mode. DETAILED DESCRIPTION

[0058] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0059] (Structure of a sphygmomanometer)

[0060] Figure 1FIG. 1 shows the appearance of a wrist-type blood pressure monitor 100 according to an embodiment of the present invention. The blood pressure monitor 100 generally comprises a blood pressure measurement cuff 20 to be worn on a left wrist 90 (see FIG. 20 to be described later) as a measurement site. Figure 3 ); and a main body 10, which is integrally mounted on the cuff 20.

[0061] The cuff 20 is a common cuff for a wrist-type blood pressure monitor, and has a long and narrow band shape so as to be wrapped around the left wrist 90 along the circumferential direction. The cuff 20 contains a fluid bag 22 (see FIG. 1 ) for compressing the left wrist 90. Figure 2 ). In addition, in order to always maintain the cuff 20 in an annular shape, a loop having appropriate flexibility may be provided in the cuff 20.

[0062] like Figure 3 As shown, the main body 10 is integrally attached to a substantially central portion in the longitudinal direction of the band-shaped cuff 20. In this example, the portion where the main body 10 is to be attached corresponds to the palm side (palm side surface) 90a of the left wrist 90 when worn.

[0063] The main body 10 has a flat, substantially rectangular parallelepiped shape along the outer peripheral surface of the cuff 20. The main body 10 is formed to be small and thin so as not to disturb the sleep of the user (in this example, the subject, and the same applies hereinafter). In addition, the corners of the main body 10 are rounded (the corners are rounded).

[0064] like Figure 1 As shown, a display 50 constituting a display screen and an operation unit 52 for inputting instructions from a user are provided on a surface (top surface) on the side farthest from the left wrist 90 among the outer surfaces of the main body 10 .

[0065] In this example, the display 50 is composed of an LCD (Liquid Crystal Display), and displays predetermined information according to a control signal from a CPU (Central Processing Unit) 110 described later. In this example, the highest blood pressure (unit: mmHg), the lowest blood pressure (unit: mmHg), and the pulse (unit: beats / minute) are displayed. In addition, the display 50 can be composed of an organic EL (Electro Luminescence) display, and can also include an LED (Light Emitting Diode).

[0066] The operation unit 52 inputs an operation signal corresponding to the user's instruction to the CPU 110 described later. In this example, the operation unit 52 includes: a measurement switch 52A, which serves as a measurement instruction input unit for receiving the user's blood pressure measurement instruction; and a nighttime measurement switch 52B, which serves as a mode operation unit for receiving an instruction to switch the mode between a normal blood pressure measurement mode and a nighttime blood pressure measurement mode. Here, the "normal blood pressure measurement mode" refers to a mode in which blood pressure measurement is performed according to the blood pressure measurement instruction when a blood pressure measurement instruction is input through the measurement switch 52A. The "nighttime blood pressure measurement mode" refers to a mode in which blood pressure measurement is automatically started according to a predetermined schedule so that the user can measure the blood pressure value during sleep. The predetermined schedule refers to a plan to perform measurements at a predetermined time such as 1 a.m., 2 a.m., 3 a.m., etc., or a plan to perform measurements once every two hours, for example, starting from pressing the nighttime measurement switch 52B.

[0067] Specifically, in this example, both the measurement switch 52A and the nighttime measurement switch 52B are momentary (automatic reset) switches, which are in the on state only while being pressed, and return to the off state when released.

[0068] When the measurement switch 52A is pressed once while the sphygmomanometer 100 is in the normal blood pressure measurement mode, it indicates a blood pressure measurement instruction, and the cuff 20 temporarily compresses the measured part (left wrist 90), and the blood pressure measurement is performed using the oscillometric method. When the measurement switch 52A is pressed again during the blood pressure measurement (for example, during the cuff 20 being pressurized), it indicates an instruction to stop the blood pressure measurement, and the blood pressure measurement is stopped immediately.

[0069] When the nighttime measurement switch 52B is pressed once while the sphygmomanometer 100 is in the normal blood pressure measurement mode, it indicates an instruction to switch to the nighttime blood pressure measurement mode, and the sphygmomanometer 100 switches from the normal blood pressure measurement mode to the nighttime blood pressure measurement mode. In the nighttime blood pressure measurement mode, as described above, blood pressure measurement using the oscillometric method automatically starts according to a predetermined schedule. When the nighttime measurement switch 52B is pressed again while the sphygmomanometer 100 is in the nighttime blood pressure measurement mode, it indicates an instruction to stop the nighttime blood pressure measurement mode, and the sphygmomanometer 100 switches from the nighttime blood pressure measurement mode to the normal blood pressure measurement mode.

[0070] Even during the period when the sphygmomanometer 100 is in the nighttime blood pressure measurement mode, the user can instruct blood pressure measurement in an intervening manner by pressing the measurement switch 52A, unlike the above-mentioned predetermined schedule. At this time, in response to the intervening blood pressure measurement instruction, the measured part (left wrist 90) is temporarily compressed by the cuff 20 to perform blood pressure measurement using the oscillometric method.

[0071] Figure 2 The block structure of the sphygmomanometer 100 is shown.

[0072] As described above, the cuff 20 includes the fluid bag 22 for compressing the left wrist 90 as the measurement site. The fluid bag 22 and the main body 10 are connected via the air pipe 39 so that the fluid can flow.

[0073] In addition to the display 50 and the operation unit 52, the main body 10 is equipped with a CPU 110 as a control unit, a memory 51 as a storage unit, a power supply unit 53, a pressure sensor 31, a pump 32, and a valve 33. In addition, the main body 10 is equipped with an A / D conversion circuit 310 that converts the output of the pressure sensor 31 from an analog signal to a digital signal, a pump drive circuit 320 that drives the pump 32, and a valve drive circuit 330 that drives the valve 33. The pressure sensor 31, the pump 32, and the valve 33 are connected to the fluid bag 22 via the air pipe 39 so that the fluid can flow.

[0074] The memory 51 stores programs for controlling the sphygmomanometer 100, data for controlling the sphygmomanometer 100, setting data for setting various functions of the sphygmomanometer 100, and data of blood pressure measurement results. In addition, the memory 51 is used as a working memory when executing the program. In particular, in this example, the memory 51 operates as an algorithm storage unit, and stores an algorithm for a sitting position and an algorithm for a supine position as algorithms for calculating blood pressure using the oscillometric method.

[0075] Among them, Figure 4A As shown, the "sitting position" refers to a posture in which the user 80 wearing the blood pressure monitor 100 on the left wrist 90 sits on a chair 97 or the like, places the left elbow on a table 98, and raises the left wrist 90 in a forward tilt relative to the torso (hand up, elbow down), thereby maintaining the left wrist 90 (and the blood pressure monitor 100) at the height level of the heart 81. Since this posture eliminates the height difference between the left wrist 90 of the user 80 and the heart 81, this posture is recommended to improve the accuracy of blood pressure measurement. On the other hand, if Figure 4B As shown in the figure, the "supine position" refers to the position in which the user 80 wearing the blood pressure monitor 100 on the left wrist 90 lies on his back on a horizontal floor 99 or the like with his left elbow extended along the trunk. In this position, the difference in height ΔH between the left wrist 90 (and the blood pressure monitor 100) of the user 80 and the heart 81 (the height of the heart 81 is higher than the height of the left wrist 90) occurs, so the blood pressure measurement value is biased. In addition, in the sitting position ( Figure 4A ) with the left elbow bent, and in the supine position ( Figure 4B) when the left elbow is extended, so the flexion and extension of the left elbow may cause deviation in the blood pressure measurement value. In order to eliminate the deviation of the blood pressure measurement value in the supine position relative to the blood pressure measurement value in the sitting position, it is preferred to change the blood pressure calculation algorithm for the case where the blood pressure measurement is performed in the supine position relative to the blood pressure calculation algorithm for the case where the blood pressure measurement is performed in the sitting position. For this reason, in this example, the memory 51 stores an algorithm for the sitting position and an algorithm for the supine position as algorithms for calculating blood pressure using the oscillometric method. The specific method of blood pressure calculation using these algorithms for the sitting position and the algorithm for the supine position will be described later.

[0076] Figure 2 The CPU 110 shown in FIG. 1 controls the overall operation of the sphygmomanometer 100. Specifically, the CPU 110 operates as a pressure control unit according to a program for controlling the sphygmomanometer 100 stored in the memory 51, and controls the driving of the pump 32 or the valve 33 in response to an operation signal from the operation unit 52. In addition, the CPU 110 operates as a blood pressure calculation unit, calculates the blood pressure value using an algorithm for calculating the blood pressure using the oscillometric method, and controls the display 50 and the memory 51.

[0077] In this example, the power supply unit 53 is composed of a rechargeable battery and supplies power to the CPU 110 , the pressure sensor 31 , the pump 32 , the valve 33 , the display 50 , the memory 51 , the A / D conversion circuit 310 , the pump drive circuit 320 , and the valve drive circuit 330 .

[0078] The pump 32 supplies air as a fluid to the fluid bag 22 through the air piping 39 to increase the pressure (cuff pressure) in the fluid bag 22 contained in the cuff 20. The valve 33 is opened and closed to discharge the air of the fluid bag 22 through the air piping 39 or to seal the air in the fluid bag 22 to control the cuff pressure. The pump drive circuit 320 drives the pump 32 based on the control signal provided by the CPU 110. The valve drive circuit 330 opens and closes the valve 33 based on the control signal provided by the CPU 110.

[0079] The pressure sensor 31 and the A / D conversion circuit 310 operate as a pressure detection unit for detecting the pressure of the cuff. In this example, the pressure sensor 31 is a piezo-resistance pressure sensor, and outputs the pressure (cuff pressure) in the fluid bag 22 contained in the cuff 20 as resistance caused by the piezoelectric impedance effect through the air piping 39. The A / D conversion circuit 310 converts the output (resistance) of the pressure sensor 31 from an analog signal to a digital signal and outputs it to the CPU 110. In this example, the CPU 110 operates as an oscillation circuit that oscillates at a frequency corresponding to the resistance from the pressure sensor 31, and obtains a signal indicating the cuff pressure based on the oscillation frequency.

[0080] (Blood pressure calculation method)

[0081] Figure 5 The flow of actions when the user measures blood pressure in the normal blood pressure measurement mode using the blood pressure meter 100 is shown. In this example, if the measurement switch 52A is pressed continuously for, for example, 3 seconds or more in the power-off state, the power is turned on and the normal blood pressure measurement mode is changed by default.

[0082] like Figure 4A As shown, the user 80 wearing the blood pressure monitor 100 on the left wrist 90 is in a sitting position.

[0083] In this state, if Figure 5 As shown in step S1, when the user presses the measurement switch 52A provided on the main body 10 and inputs a blood pressure measurement instruction, the CPU 110 initializes the pressure sensor 31 (step S2). Specifically, the CPU 110 initializes the processing storage area, and closes (stops) the pump 32, and adjusts the pressure sensor 31 to 0 mmHg (the atmospheric pressure is set to 0 mmHg) while the valve 33 is opened.

[0084] Next, the CPU 110 closes the valve 33 via the valve drive circuit 330 (step S3), and then turns on (starts) the pump 32 via the pump drive circuit 320 to start pressurizing the cuff 20 (fluid bag 22) (step S4). At this time, the CPU 110 supplies air from the pump 32 to the fluid bag 22 through the air pipe 39, and based on the output of the pressure sensor 31, as shown in FIG. Figure 7 As shown in (A) of FIG. 1 , the pressurization speed of the cuff pressure PC, which is the pressure in the fluid bag 22, is controlled.

[0085] Next, in Figure 5 In step S5, the CPU 110 operates as a blood pressure calculation unit, based on the pulse wave signal SM (the pulse wave variation component included in the output of the pressure sensor 31) acquired at that time (refer to Figure 7(B)), an algorithm for sitting position stored in memory 51 is used to attempt to calculate blood pressure values ​​(maximum blood pressure (systolic blood pressure) and minimum blood pressure (diastolic blood pressure)).

[0086] At this point, if the blood pressure value cannot be calculated due to insufficient data ("No" in step S6), the processing of steps S4 to S6 is repeated unless the cuff pressure PC reaches the upper limit pressure (for example, predetermined to 300 mmHg for safety).

[0087] The CPU 110 calculates the blood pressure value in the following manner. That is, the blood pressure value obtained from the cuff pressure PC when the cuff 20 is in the process of being pressurized is calculated. Figure 7 The sequence of pulse wave amplitudes (peak to peak) formed by the pulse wave signal SM shown in (B) is set Figure 7 At the same time, a predetermined ratio α used when sitting is set for the maximum value AmpMax of the envelope ENV. dia , α sys There are two threshold levels THD1 and THS1. THD1 is the threshold level for diastolic blood pressure and is set to THD1 = α dia ×AmpMax. In addition, THS1 is a threshold level for systolic blood pressure and is set to THS1 = α sys ×AmpMax. As an example, set α dia =0.75, and set α sys =0.4 (that is, THD1 is set to 0.75×AmpMax, and THS1 is set to 0.4×AmpMax.) Then, Figure 7 As shown in (A) of FIG. 1 , the cuff pressure PC at the time when the envelope ENV crosses the threshold levels THD1 and THS1 is calculated as the lowest blood pressure (diastolic blood pressure) BPdia1 and the highest blood pressure (systolic blood pressure) BPsys1, respectively.

[0088] When the blood pressure value is calculated in this manner (YES in step S6 ), the CPU 110 turns off the pump 32 (step S7 ), opens the valve 33 (step S8 ), and performs control to discharge the air in the cuff 20 (fluid bag 22 ).

[0089] Then, the CPU 110 displays the calculated blood pressure value on the display 50 (step S9 ), and performs control to store the blood pressure value in the memory 51 .

[0090] Figure 6 The flowchart shows the operation flow when the user measures blood pressure in the nighttime blood pressure measurement mode using the blood pressure meter 100. At the beginning of this flow, the blood pressure meter 100 is in the normal blood pressure measurement mode.

[0091] like Figure 6 As shown in step S11 of FIG. 1 , when the user presses the nighttime measurement switch 52B provided on the main body 10, the sphygmomanometer 100 switches from the normal blood pressure measurement mode to the nighttime blood pressure measurement mode. In this example, in the nighttime blood pressure measurement mode, a schedule is set for performing measurement every 2 hours from the time the nighttime measurement switch 52B is pressed to, for example, 7 a.m. In addition, the schedule is not limited to this schedule, and a schedule for performing measurement at a predetermined time such as 1 a.m., 2 a.m., or 3 a.m. may be set from the time the nighttime measurement switch 52B is pressed to, for example, 7 a.m.

[0092] With the transition to the nighttime blood pressure measurement mode, as shown in step S12 , CPU 110 operates as a first switching unit to switch the algorithm for calculating the blood pressure using the oscillometric method from the sitting position algorithm to the supine position algorithm.

[0093] Specifically, if Figure 8 As shown in , the threshold level for diastolic blood pressure is set to switch from THD1 to THD2, and the threshold level for systolic blood pressure is set to switch from THS1 to THS2. Among them, THD2 is set to 0.6×AmpMax, and THS2 is set to 0.5×AmpMax. This is equivalent to changing the ratio α to the maximum value AmpMax of the envelope ENV dia The value of the ratio α to the maximum value AmpMax of the envelope ENV was changed from 0.75 for the sitting position to 0.6 for the supine position. sys The ratio α is changed from 0.4 for sitting position to 0.5 for supine position. dia , α sys The change is used to eliminate the supine position ( Figure 4B ) relative to the blood pressure values ​​measured in the sitting position ( Figure 4A ) when the blood pressure measurement value is biased.

[0094] In addition, the memory 51 preferably has a flag indicating the currently set algorithm among the algorithm for the sitting position and the algorithm for the supine position. In this case, the CPU 110 can easily recognize the currently set algorithm by referring to the flag.

[0095] Next, if Figure 6 As shown in step S13, CPU 110 determines whether it is the measurement time specified in the schedule (for the nighttime blood pressure measurement mode). If it is not the measurement time specified in the schedule ("No" in step S13), the CPU 110 waits for the measurement time specified in the schedule to become the measurement time specified in the schedule ("No" in step S25) unless the measurement switch 52A is pressed.

[0096] If the measurement time specified in the above schedule is reached ("Yes" in step S13), Figure 6 As shown in steps S14 to S16, CPU 110 Figure 5 Blood pressure measurement is started in the same manner as steps S2 to S4. That is, CPU 110 first initializes pressure sensor 31 (step S14).

[0097] Next, the CPU 110 closes the valve 33 via the valve drive circuit 330 (step S15), and then turns on (starts) the pump 32 via the pump drive circuit 320 to start pressurizing the cuff 20 (fluid bag 22) (step S16). Figure 7 In the same manner as in the case shown in (A), the pressure increase speed of the cuff pressure PC is controlled.

[0098] Next, in Figure 6 In step S17, the CPU 110 operates as a blood pressure calculation unit, and calculates the blood pressure based on the pulse wave signal SM (the pulse wave variation component included in the output of the pressure sensor 31) acquired at that time (with Figure 7 (B) is the same as the situation shown in FIG. 1 ), and the currently set algorithm (the algorithm for the supine position at this moment) is used to try to calculate the blood pressure values ​​(the highest blood pressure (systolic blood pressure) and the lowest blood pressure (diastolic blood pressure)).

[0099] At this point, if the blood pressure value cannot be calculated due to insufficient data ("No" in step S18), the processing of steps S16 to S18 is repeated unless the cuff pressure PC reaches the upper limit pressure (for example, predetermined to 300 mmHg for safety reasons).

[0100] Here, CPU 110 calculates the blood pressure value in the following manner. That is, for the sequence of pulse wave amplitudes (peak to peak) formed by the pulse wave signal SM obtained from the cuff pressure PC when the cuff 20 is in the process of being pressurized, Figure 8 The envelope ENV (with Figure 7 Then, the cuff pressure PC at the moment when the envelope ENV crosses the currently set supine position threshold levels THD2 (= 0.6 × AmpMax) and THS2 (= 0.5 × AmpMax) is calculated as the minimum blood pressure (diastolic blood pressure) BPdia2 and the maximum blood pressure (systolic blood pressure) BPsys2, respectively.

[0101] In the nighttime blood pressure measurement mode, it is usually desirable for the user to be in the supine position. Therefore, by using the algorithm for the supine position, the blood pressure values ​​(maximum blood pressure and minimum blood pressure) can be calculated stably and with high accuracy.

[0102] When the blood pressure value is calculated in this manner (YES in step S18 ), the CPU 110 turns off the pump 32 (step S19 ), opens the valve 33 (step S20 ), and performs control to discharge the air in the cuff 20 (fluid bag 22 ).

[0103] Then, the CPU 110 displays the calculated blood pressure value on the display 50 (step S21 ), and performs control to store the blood pressure value in the memory 51 .

[0104] In this way, when a blood pressure measurement specified in the above schedule is completed, in step S22, CPU110 determines whether all blood pressure measurements specified in the above schedule are completed. Among them, as long as there is a blood pressure measurement scheduled according to the above schedule ("not completed" in step S22), the currently set algorithm is the algorithm for the supine position ("no" in step S23), so it returns directly to step S13. Then, wait for the next measurement time specified in the above schedule ("no" in step S13, "no" in step S25).

[0105] If the next measurement time specified in the above schedule is reached ("Yes" in step S13), CPU110 repeats the processing of steps S14 to S21. Furthermore, in step S22, CPU110 determines whether all blood pressure measurements specified in the above schedule are completed. As long as there are blood pressure measurements scheduled according to the above schedule ("Not Completed" in step S22), CPU110 directly returns to step S13 ("No" in step S23). Then, it waits for the next measurement time specified in the above schedule ("No" in step S13, "No" in step S25).

[0106] In addition, even when the sphygmomanometer 100 is in the nighttime blood pressure measurement mode, the user can instruct blood pressure measurement in an interrupt manner by pressing the measurement switch 52A, which is different from the above-mentioned predetermined schedule ("Yes" in step S25). At this time, it is desirable for the user to be in a sitting position rather than a supine position. Therefore, the CPU 110 operates as a second switching unit and sets the algorithm for calculating blood pressure using the oscillometric method to be switched from the algorithm for the supine position to the algorithm for the sitting position (step S26).

[0107] Next, as shown in steps S14 to S16, the CPU 110 starts the blood pressure measurement corresponding to the inserted blood pressure measurement instruction. That is, the CPU 110 first initializes the pressure sensor 31 (step S14).

[0108] Next, the CPU 110 closes the valve 33 via the valve drive circuit 330 (step S15), and then turns on (starts) the pump 32 via the pump drive circuit 320 to start pressurizing the cuff 20 (fluid bag 22) (step S16). Figure 7 In the same manner as in the case shown in (A), the pressure increase speed of the cuff pressure PC is controlled.

[0109] Next, in Figure 6 In step S17, the CPU 110 operates as a blood pressure calculation unit, and calculates the blood pressure based on the pulse wave signal SM (the pulse wave variation component included in the output of the pressure sensor 31) acquired at that time (with Figure 7 (B) is the same as the situation shown in FIG. 1 ), and the currently set algorithm (the algorithm for sitting at this moment) is used to try to calculate the blood pressure values ​​(maximum blood pressure (systolic blood pressure) and minimum blood pressure (diastolic blood pressure)).

[0110] At this point, if the blood pressure value cannot be calculated due to insufficient data ("No" in step S18), the processing of steps S16 to S18 is repeated unless the cuff pressure PC reaches the upper limit pressure (for example, predetermined to 300 mmHg for safety reasons).

[0111] The CPU 110 calculates the blood pressure value in the following manner. That is, for the sequence of pulse wave amplitudes (peak to peak) formed by the pulse wave signal SM obtained from the cuff pressure PC when the cuff 20 is in the process of being pressurized, set Figure 8 Then, the cuff pressure PC at the moment when the envelope ENV crosses the currently set threshold levels THD1 (= 0.75 × AmpMax) and THS1 (= 0.4 × AmpMax) for the sitting position is calculated as the minimum blood pressure (diastolic blood pressure) BPdia1 and the maximum blood pressure (systolic blood pressure) BPsys1, respectively.

[0112] When the blood pressure measurement is instructed by pressing the measurement switch 52A ("Yes" in step S25), the user is preferably in a sitting position rather than a supine position. Therefore, by using an algorithm for the sitting position, the blood pressure values ​​(maximum blood pressure and minimum blood pressure) can be calculated stably and accurately.

[0113] When the blood pressure value is calculated in this manner (YES in step S18 ), the CPU 110 turns off the pump 32 (step S19 ), opens the valve 33 (step S20 ), and performs control to discharge the air in the cuff 20 (fluid bag 22 ).

[0114] Then, the CPU 110 displays the calculated blood pressure value on the display 50 (step S21 ), and performs control to store the blood pressure value in the memory 51 .

[0115] When the blood pressure measurement corresponding to the inserted blood pressure measurement instruction is completed in this way, in step S22, CPU110 determines whether all blood pressure measurements specified in the above schedule are completed. It is assumed that there are blood pressure measurements scheduled according to the above schedule ("not completed" in step S22). Since the currently set algorithm is the algorithm for sitting position ("yes" in step S23), CPU110 acts as the third switching unit to set the algorithm used for blood pressure calculation using the oscillometric method from the above sitting position algorithm to the above supine position algorithm (step S24). Then, return to step S13. Then, wait for the next measurement time specified in the above schedule ("no" in step S13, "no" in step S25).

[0116] If it is the next measurement time specified in the above schedule ("Yes" in step S13), CPU110 repeats the processing of steps S14 to S21. In this way, even after the blood pressure measurement corresponding to the inserted blood pressure measurement instruction is completed, the blood pressure measurement is automatically started according to the above schedule. At this time, in step S18, CPU110 acts as a blood pressure calculation unit and calculates the lowest blood pressure (diastolic blood pressure) BPdia2 and the highest blood pressure (systolic blood pressure) BPsys2 using the algorithm for the supine position.

[0117] In the nighttime blood pressure measurement mode, as described above, it is generally desirable for the user to be in a supine position. Therefore, by using the supine position algorithm after completing the blood pressure measurement corresponding to the inserted blood pressure measurement instruction, the blood pressure values ​​(maximum blood pressure and minimum blood pressure) can be calculated stably and accurately.

[0118] When all blood pressure measurements specified in the above schedule are completed in this way ("end" in step S22), CPU 110 operates as a fourth switching unit to switch the algorithm for calculating blood pressure using the oscillometric method from the algorithm for the supine position to the algorithm for the sitting position (step S27). Then, the above nighttime blood pressure measurement mode ends.

[0119] Thus, after the nighttime blood pressure measurement mode ends, for example, when the normal blood pressure measurement mode is started by default, Figure 5 In step S5, CPU 110 operates as a blood pressure calculation unit and can use an algorithm for sitting to calculate the blood pressure value, so as to perform blood pressure calculation using the above-mentioned oscillometric method. Therefore, blood pressure calculation in the normal blood pressure measurement mode can be accurately performed.

[0120] As can be seen from the above, according to the sphygmomanometer 100, in the nighttime blood pressure measurement mode, when blood pressure measurement is performed in response to an inserted blood pressure measurement instruction, unlike the predetermined schedule, the blood pressure value can be stably and accurately calculated.

[0121] In addition, the sphygmomanometer 100 is a type that compresses the wrist (the left wrist 90 in the above example, but the right wrist may also be used) as the measured part, so it is expected that the degree of interference with the sleep of the user (subject) is less than that of the type that compresses the upper arm (Imai et al., "Development and evaluation of a home nocturnal blood pressure monitoring system using a wrist-cuff device", Blood Pressure Monitoring 2018, 23, P318-326). Therefore, the sphygmomanometer 100 is suitable for nighttime blood pressure measurement.

[0122] Furthermore, since the blood pressure monitor 100 is integrally and compactly configured as a wrist blood pressure monitor, the operation by the user is convenient.

[0123] (Variation Example)

[0124] In the above-mentioned embodiment, in the operation flow of the nighttime blood pressure measurement mode of the sphygmomanometer 100 ( Figure 6 ), including the following processing: pressing the measurement switch 52A to determine whether a blood pressure measurement instruction is issued upon insertion (step S25); the CPU 110 acts as a second switching unit to set the algorithm for calculating blood pressure using the oscillometric method to switch from the algorithm for the supine position to the algorithm for the sitting position (step S26). However, this is not limited to this, and these processing (steps S25, S26) may also be omitted. In this case, the following processing can be omitted at the same time: determining whether the currently set algorithm is an algorithm for the sitting position (step S23); and the CPU 110 acts as a third switching unit to set the algorithm for calculating blood pressure using the oscillometric method to switch from the above-mentioned sitting position algorithm to the above-mentioned supine position algorithm (step S24). Thereby, the action flow of the nighttime blood pressure measurement mode can be simplified ( Figure 6 ).

[0125] In the above-mentioned embodiment, in the operation flow of the nighttime blood pressure measurement mode of the sphygmomanometer 100 ( Figure 6), including the following processing: after all blood pressure measurements specified in the schedule are completed ("end" in step S22), CPU110 acts as a fourth switching unit and sets the processing of switching the algorithm used for calculating blood pressure using the oscillometric method from the algorithm for the supine position to the algorithm for the sitting position (step S27). However, this is not limited to this, and this processing (step S27) can also be omitted. In this way, the action flow of the nighttime blood pressure measurement mode can be simplified ( Figure 6 ). In addition, in this case, after the user finishes the nighttime blood pressure measurement, the user temporarily turns off the power of the sphygmomanometer 100 (in this example, when the measurement switch 52A is continuously pressed for, for example, more than 3 seconds in the power-on state, the power is turned off). When the user wishes to perform nighttime blood pressure measurement again, the sphygmomanometer 100 is turned on (as described above, when the measurement switch 52A is continuously pressed for, for example, more than 3 seconds in the power-off state, the power is turned on). After the default is temporarily set to the normal blood pressure measurement mode (algorithm for sitting position), the nighttime blood pressure measurement mode (algorithm for supine position) can be set by pressing the nighttime measurement switch 52B.

[0126] In the above embodiment, the blood pressure is calculated while the cuff 20 (fluid bag 22) is being pressurized, but the present invention is not limited thereto. The blood pressure may be calculated while the cuff 20 is being depressurized.

[0127] In addition, in the above embodiment, the measurement instruction input unit and the mode operation unit are respectively provided with the measurement switch 52A and the night measurement switch 52B provided on the main body 10, but the present invention is not limited thereto. The measurement instruction input unit and the mode operation unit may also be constituted by a communication unit that receives instructions from a smartphone or the like outside the sphygmomanometer 100 via wireless communication, for example.

[0128] In the above embodiment, the main body 10 and the cuff 20 are integrally provided, but the present invention is not limited thereto. The main body 10 may be configured as a separate body from the cuff 20 and connected to the cuff 20 (fluid bag 22) via a flexible air tube so that fluid can flow.

[0129] The above blood pressure calculation method (especially, Figure 6 The blood pressure calculation method is recorded as software (computer program) in a recording medium capable of storing data in a non-temporary manner, such as a CD (compact disc), a DVD (digital versatile disc), or a flash memory. By installing the software recorded in such a recording medium in a substantial computer device such as a personal computer, a PDA (personal digital assistant), or a smart phone, the computer device can be made to execute the blood pressure calculation method.

[0130] The above embodiments are illustrative and can be variously modified without departing from the scope of the present invention. The above multiple embodiments can be established separately, but the embodiments can also be combined with each other. In addition, various features in different embodiments can also be established separately, but the features in different embodiments can also be combined with each other.

[0131] Description of reference numerals:

[0132] 10: Main body

[0133] 20: Blood pressure measurement cuff

[0134] 50: Display

[0135] 51: Memory

[0136] 52: Operation Department

[0137] 52A: Measuring switch

[0138] 52B: Night measurement switch

[0139] 110: CPU

Claims

1. A sphygmomanometer that measures blood pressure using an oscillometric method by temporarily compressing a wrist as a measured part with a blood pressure measurement cuff, wherein: The sphygmomanometer has: A main body, which is integrally provided with the blood pressure measurement cuff; a single measurement switch, serving as a measurement instruction input portion for inputting a blood pressure measurement instruction, disposed on the outer surface of the main body; a mode operation unit for inputting an instruction for switching the mode between a normal blood pressure measurement mode for performing blood pressure measurement in accordance with a blood pressure measurement instruction input by the single measurement switch and a nighttime blood pressure measurement mode for automatically starting blood pressure measurement in accordance with a predetermined schedule; an algorithm storage unit storing an algorithm for a sitting position and an algorithm for a supine position as algorithms for calculating blood pressure using an oscillometric method; a first switching unit configured to switch the algorithm for calculating the blood pressure using the oscillometric method from the sitting position algorithm to the supine position algorithm when the normal blood pressure measurement mode is switched to the nighttime blood pressure measurement mode by the mode operation unit; a second switching unit configured to switch the algorithm for calculating the blood pressure using the oscillometric method from the algorithm for the supine position to the algorithm for the sitting position using only the blood pressure measurement instruction input in the inserted manner as a trigger in the nighttime blood pressure measurement mode when the blood pressure measurement instruction is input in an inserted manner by operating the single measurement switch, unlike the predetermined schedule, so as to perform the blood pressure measurement corresponding to the inserted blood pressure measurement instruction; as well as The blood pressure calculation unit calculates the blood pressure value based on the pressure of the blood pressure measurement cuff when the blood pressure measurement cuff is in the process of pressurization or depressurization, using an algorithm currently set for blood pressure calculation using the oscillometric method.

2. The sphygmomanometer according to claim 1, wherein: The mode operation unit includes a single mode switching switch provided on the outer surface of the main body. When the normal blood pressure measurement mode is switched to the nighttime blood pressure measurement mode by operating the single mode switching switch serving as the mode operating unit, the first switching unit only uses the switching to the nighttime blood pressure measurement mode as a trigger to switch the algorithm for calculating the blood pressure using the oscillometric method from the sitting position algorithm to the supine position algorithm.

3. The sphygmomanometer according to claim 1 or 2, wherein: have: The third switching unit, when the blood pressure measurement corresponding to the inserted blood pressure measurement instruction is completed, is set to switch the algorithm used to calculate the blood pressure using the oscillometric method from the algorithm for the sitting position to the algorithm for the supine position as long as there is another blood pressure measurement scheduled according to the schedule.

4. The sphygmomanometer according to claim 1 or 2, wherein: have: The fourth switching unit is configured to switch the algorithm for calculating the blood pressure using the oscillometric method from the algorithm for the supine position to the algorithm for the sitting position when all the blood pressure measurements specified in the schedule are completed.

5. The sphygmomanometer according to claim 1 or 2, wherein: The blood pressure monitor includes a control unit. The control unit is configured as follows: After all blood pressure measurements specified in the schedule have been completed, maintaining the algorithm set for oscillometric blood pressure calculations, When the power of the sphygmomanometer is turned on again after being temporarily turned off, the algorithm used for calculating the blood pressure using the oscillometric method is set to the sitting algorithm by default.

6. The sphygmomanometer according to claim 1 or 2, wherein: The main body is equipped with the algorithm storage unit, each switching unit, a pressure control unit that controls the pressure of the blood pressure measurement cuff, and the blood pressure calculation unit.

7. A blood pressure calculation method, used for the sphygmomanometer according to claim 1, wherein: The blood pressure calculation method includes the following processing: When the mode operation unit switches from the normal blood pressure measurement mode to the nighttime blood pressure measurement mode, the first switching unit is configured to switch the algorithm for calculating the blood pressure using the oscillometric method from the sitting position algorithm to the supine position algorithm. In the nighttime blood pressure measurement mode, when a blood pressure measurement instruction is inputted in an interpolated manner by operating the single measurement switch, unlike the predetermined schedule, the second switching unit uses only the interpolated input blood pressure measurement instruction as a trigger to switch the algorithm for calculating the blood pressure using the oscillometric method from the algorithm for the supine position to the algorithm for the sitting position, so as to perform the blood pressure measurement corresponding to the interpolated blood pressure measurement instruction. When the blood pressure measurement cuff is in a pressurization process or a depressurization process, the blood pressure calculation unit calculates the blood pressure value based on the pressure of the blood pressure measurement cuff using an algorithm currently set for blood pressure calculation using the oscillometric method. 8 . A storage medium storing a program for causing a computer to execute the blood pressure calculation method according to claim 7 .

Images