JP5092885B2 - Electronic blood pressure monitor - Google Patents

Description

  The present invention relates to an electronic sphygmomanometer, and more particularly to an electronic sphygmomanometer that measures blood pressure according to an oscillometric method or a microphone method.

  Blood pressure is one of the indices for analyzing cardiovascular diseases, and risk analysis based on blood pressure is effective in preventing cardiovascular diseases such as stroke, heart failure and myocardial infarction. In particular, blood pressure measurement outside the hospital, such as at home, can be performed at the same time every day in a stable environment for a long period of time, which has proved to be highly predictive of cardiovascular diseases. . Therefore, there is a tendency to place importance on home blood pressure even in the medical field.

  The conventional electronic blood pressure monitor pressurizes the pressure in the cuff wound around the measurement site higher than the maximum blood pressure. Thereafter, in the process of gradually reducing the pressure in the cuff, the pulsation generated in the artery is detected by the pressure sensor through the cuff. A predetermined algorithm is applied to the pressure in the cuff (cuff pressure) and the magnitude of the pulsation (pulse wave amplitude) at that time to determine the maximum blood pressure and the minimum blood pressure (oscillometric method). The blood pressure calculation method according to the oscillometric method uses a characteristic that the pulse wave amplitude increases rapidly near the maximum blood pressure and rapidly decreases near the minimum blood pressure (for example, Patent Document 1).

  In addition, by detecting the blood flow sound (Korotkoff sound) that occurs and disappears depending on the change in blood flow during pressure increase / decrease in the cuff with a Korotkoff sound detector such as a microphone, the systolic blood pressure and the diastolic blood pressure are detected. Some of them determine (microphone method). The blood pressure calculation method according to the microphone method uses the feature that the Korotkoff sound occurs at the highest blood pressure and disappears (or is weak) near the lowest blood pressure (for example, Patent Document 2).

  There are the following two methods for reducing pressure in these conventional electronic blood pressure monitors. The first is a method of depressurizing at a constant speed (constant speed depressurization) (eg, Patent Documents 1 and 3). The second is a method of reducing pressure stepwise (step pressure reduction) at a constant interval (for example, Patent Document 4).

  The electronic sphygmomanometer according to the oscillometric method determines the blood pressure based on the change of the pulse wave amplitude that appears during the pressure increase / decrease as described above. Therefore, the greater the number of pulse wave amplitudes acquired during pressure increase / decrease, the better the measurement accuracy. In Patent Document 3, it is sufficient that there is information on five or more pulse wave amplitudes between the systolic blood pressure and the systolic blood pressure, that is, between the pulse pressures, and the decompression speed can be set based on such regulations. It is disclosed.

However, in actual measurement, information on pulse wave amplitude may become unusable due to the subject moving his body or irregular pulse waves. Further, noise may be mixed in the pulse wave amplitude or the pulse wave amplitude may be lost. In such a case, it is necessary to calculate the blood pressure after performing correction by a predetermined calculation (for example, spline function interpolation or the like) from information on other pulse wave amplitudes. For example, in Patent Document 5, a weighting factor is obtained from the pressure distance between the cuff pressure corresponding to the target pulse wave amplitude and the cuff pressure corresponding to the peripheral pulse wave amplitude, and the peripheral pulse wave amplitude is multiplied by the weighting factor and corrected. ing. The envelope of the pulse wave amplitude sequence used for blood pressure calculation is smoothed by performing a moving average calculation using the target pulse wave amplitude and the weighted peripheral amplitude.
Japanese Patent Publication No. 3-81375 Japanese Examined Patent Publication No. 2-39249 Japanese Patent No. 3149873 Japanese Patent Publication No. 5-54782 Japanese Patent Publication No. 5-317274

  When the pulse wave amplitude is corrected as in Patent Document 5, since correction is performed based on a small amount of information, an error may occur in the measured (calculated) blood pressure value. Therefore, in order to improve the measurement accuracy, it is necessary to depressurize (or pressurize) at the slowest possible speed so that correction is not necessary.

  The same applies when blood pressure is measured according to the microphone method. Since Korotkoff sounds are generated by pulsation, the decompression speed needs to be 2 to 3 mmHg per beat in order to detect all Korotkoff sounds.

  Although the above has been described with respect to constant pressure reduction, the same applies to step pressure reduction. That is, in order to improve measurement accuracy, it is necessary to make the pressure interval for depressurization as small as possible (specifically, 2 to 3 mmHg).

  However, regardless of which method is used, if the amount of change in pressure per unit time is reduced (decreasing pressure or pressurizing speed is reduced), the time for pressing the measurement site becomes longer. If it does so, a to-be-measured person will feel discomfort and a pain.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electronic device capable of measuring blood pressure with high accuracy in a short time by an oscillometric method or a microphone method. To provide a sphygmomanometer.

  An electronic sphygmomanometer according to an aspect of the present invention includes a cuff for wrapping around a predetermined measurement site of a measurement subject, an adjustment unit for adjusting the pressure in the cuff by pressurization and decompression, and detecting the pressure in the cuff A pressure detecting means for controlling the pressure in the cuff, and a control means for controlling the adjusting means to pressurize the pressure in the cuff to a specific pressure value. And a decompression control means for controlling the adjustment means to reduce the pressure in the cuff when the pressure reaches a specific pressure value. At least one of the first pressure interval including the equivalent value and the second pressure interval including the minimum blood pressure equivalent value is reduced by the first pressure change amount per unit time, and the third pressure interval is changed to the first pressure interval. 2nd pressure change amount greater than 1 pressure change amount Under reduced pressure, the control means during decompression by decompression control means, based on the output from the pressure detecting means, further comprising a calculating means for calculating the blood pressure value of the subject.

  Preferably, the control means further includes a determining means for determining the first and second pressure intervals, and the determining means sets a predetermined pressure range before and after the maximum blood pressure equivalent value as the first pressure interval, A predetermined pressure range before and after the blood pressure equivalent value is determined as the second pressure interval.

  Preferably, the third pressure section represents a section excluding the first and / or second pressure sections in the decompression control section starting from the specific pressure value.

  Preferably, the decompression control means includes means for calculating the first pressure change amount based on the pulse rate equivalent value and a predetermined first calculation formula.

  Preferably, the decompression control means includes means for calculating a second pressure change amount based on a pulse rate equivalent value, a systolic blood pressure equivalent value, a diastolic blood pressure equivalent value, and a predetermined second calculation formula.

  Preferably, the depressurization control means further depressurizes the fourth pressure section including the average blood pressure equivalent value by the first pressure change amount, and the third pressure section depressurizes the depressurization control section starting from the specific pressure value. Represents a section excluding the first, second and / or fourth pressure sections.

  Preferably, the control means further includes an estimation means for estimating a maximum blood pressure equivalent value and a minimum blood pressure equivalent value based on an output from the pressure detection means during pressurization by the pressurization control means.

  Preferably, the estimating means further estimates at least one of a pulse rate equivalent value and an average blood pressure equivalent value.

  Preferably, the apparatus further comprises sound detection means for detecting Korotkoff sound emitted from the artery of the measurement site compressed by the cuff, and the calculation means is based on outputs from the pressure detection means and the sound detection means. Blood pressure value is calculated.

  An electronic sphygmomanometer according to another aspect of the present invention includes a cuff for winding around a predetermined measurement site of a person to be measured, an adjusting means for adjusting the pressure in the cuff by pressurization and decompression, and the pressure in the cuff. Pressure detecting means for detecting a representing pressure signal, and control means, the control means including pressurization control means for controlling the adjusting means to pressurize the pressure in the cuff to a specific pressure value. The pressurization control means performs the first pressure change per unit time in at least one of the first pressure interval including the measured blood pressure equivalent value and the second pressure interval including the diastolic blood pressure equivalent value. Pressurizing with the amount, pressurizing the third pressure section with the second pressure change amount larger than the first pressure change amount, and the control means from the pressure detection means during pressurization by the pressurization control means Based on the output, to calculate the blood pressure value of the subject Out further comprising means.

  Preferably, storage means for storing the blood pressure value calculated by the calculation means as measurement data is further provided, and the maximum blood pressure equivalent value, the minimum blood pressure equivalent value, the pulse rate equivalent value, and the average blood pressure equivalent value are stored in the storage means. It is a value based on the measured data.

  Preferably, the apparatus further includes input means for receiving an input of a maximum blood pressure equivalent value, a minimum blood pressure equivalent value, a pulse rate equivalent value, and an average blood pressure equivalent value from the outside.

  According to the present invention, blood pressure can be measured in a short time and with high accuracy.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

  The electronic sphygmomanometer (hereinafter referred to as “sphygmomanometer”) in the present embodiment measures blood pressure by an oscillometric method. First, a general blood pressure measurement method based on the oscillometric method will be described with reference to FIG.

  FIG. 15A shows the cuff pressure (unit: mmHg) gradually increased and decreased in the conventional blood pressure measurement method along the time axis, and FIG. 15B shows the same time axis. Along with this, the pulse wave amplitude (unit: mmHg) superimposed on the cuff pressure is partially shown.

  Referring to FIG. 15, in a conventional general sphygmomanometer, the cuff pressure is increased to a level not less than the maximum blood pressure (maximum blood pressure equivalent value) of the measurement subject (“PC1” in the figure), and then at a constant speed. Reduce pressure. Then, at the stage where pressure is gradually reduced, the systolic blood pressure and the diastolic blood pressure are calculated by applying a predetermined algorithm to the pulse wave amplitude superimposed on the detected cuff pressure. In the oscillometric method, it has been found that the cuff pressure corresponding to the point AMAX at which the pulse wave amplitude becomes maximum during the reduction (or pressurization) of the cuff pressure is the average blood pressure (“MAP” in the figure). When the maximum pulse wave amplitude point is detected, a value obtained by multiplying the maximum point AMAX by a predetermined constant (for example, 0.5) is set as a threshold TH_SYS, and a value obtained by multiplying the maximum point AMAX by a predetermined constant (for example, 0.7). Is a threshold TH_DIA. The cuff pressure higher than the mean blood pressure (MAP) corresponding to the point where the envelope 600 of the pulse wave amplitude and the threshold value TH_SYS intersect is determined as the maximum blood pressure (“SYS” in the figure). The cuff pressure lower than the mean blood pressure (MAP) corresponding to the point where the envelope 600 of the pulse wave amplitude and the threshold TH_DIA intersect is determined as the minimum blood pressure (“DIA” in the figure).

  When the pressure reduction rate (pressure change amount per unit time) is constant, the pulse wave amplitude detection interval is also constant. In order to increase blood pressure measurement accuracy, it is necessary to slow down the pressure reduction rate in order to increase the number of pulse wave amplitudes per unit time. However, in order to eliminate the discomfort of the measurement subject due to the compression of the measurement site for a long time, it is desirable to increase the decompression speed as described above.

  Therefore, the sphygmomanometer in the present embodiment measures blood pressure in a short period of time and with high accuracy by changing the amount of change in pressure per unit time between the value corresponding to the maximum blood pressure and the value corresponding to the minimum blood pressure, and other values. . In the present embodiment, the blood pressure is measured by changing the pressure reduction speed in the constant speed pressure reduction. Note that the blood pressure may be measured by changing the pressure interval in the step pressure reduction.

  In the present embodiment, the “maximum blood pressure equivalent value” and the “minimum blood pressure equivalent value” are values that can be acquired before blood pressure value measurement (calculation), respectively. It is assumed that the blood pressure value is expressed.

  Hereinafter, the blood pressure monitor in the present embodiment will be described in detail. Note that the sphygmomanometer in the present embodiment may measure blood pressure by the microphone method.

<Appearance and configuration>
First, the appearance and configuration of the sphygmomanometer 1 according to the embodiment of the present invention will be described.

(About appearance)
FIG. 1 is an external perspective view of a sphygmomanometer 1 according to an embodiment of the present invention.

  Referring to FIG. 1, a sphygmomanometer 1 includes a main body 10 and a cuff 20 that can be wound around a wrist of a person to be measured. The main body 10 is attached to the cuff 20. On the surface of the main body 10, there are arranged a display unit 40 made of, for example, liquid crystal and an operation unit 41 for receiving instructions from a user (typically a person to be measured). The operation unit 41 includes, for example, a plurality of switches.

  In the present embodiment, the cuff 20 is described as being attached to the wrist of the measurement subject. However, the site where the cuff 20 is worn (measurement site) is not limited to the wrist, and may be, for example, the upper arm.

  The blood pressure monitor 1 according to the present embodiment will be described by taking an example in which the main body 10 is attached to the cuff 20 as shown in FIG. However, the main body part 10 and the cuff 20 may be connected by an air tube (air tube 31 in FIG. 2) as used in an upper arm blood pressure monitor.

(About hardware configuration)
FIG. 2 is a block diagram showing a hardware configuration of sphygmomanometer 1 according to the embodiment of the present invention.

  Referring to FIG. 2, cuff 20 of sphygmomanometer 1 includes an air bag 21. The air bag 21 is connected to the air system 30 via the air tube 31.

  In addition to the display unit 40 and the operation unit 41 described above, the main body unit 10 controls the air system 30, a CPU (Central Processing Unit) 100 for centrally controlling each unit and performing various arithmetic processes, A memory unit 42 for storing a program for operating and various data, a non-volatile memory (for example, a flash memory) 43 for storing measured blood pressure, a power source 44 for supplying power to the CPU 100, and a timing It includes a clock unit 45 that operates and a data input / output unit 46 for receiving data input from the outside.

  The operation unit 41 includes a power switch 41A that receives an input of an instruction for turning on or off the power supply, a measurement switch 41B that receives an instruction to start measurement, a stop switch 41C that receives an instruction to stop measurement, and a flash And a memory switch 41D for receiving an instruction to read information such as blood pressure recorded in the memory 43. The operation unit 41 may further include an ID switch (not shown) that is operated to input ID (Identification) information for identifying the measurement subject. Thereby, measurement data can be recorded and read out for each person to be measured.

  The air system 30 includes a pressure sensor 32 for detecting the pressure (cuff pressure) in the air bag 21, a pump 51 for supplying air to the air bag 21 to pressurize the cuff pressure, and the air bag 21. And a valve 52 that is opened and closed to exhaust or enclose the air.

  The main body 10 further includes an oscillation circuit 33, a pump drive circuit 53, and a valve drive circuit 54 in association with the air system 30.

  The pressure sensor 32 is a capacitance-type pressure sensor, and the capacitance value changes depending on the cuff pressure. The oscillation circuit 33 outputs an oscillation frequency signal corresponding to the capacitance value of the pressure sensor 32 to the CPU 100. The CPU 100 detects a pressure by converting a signal obtained from the oscillation circuit 33 into a pressure. The pump drive circuit 53 controls the drive of the pump 51 based on a control signal given from the CPU 100. The valve drive circuit 54 performs opening / closing control of the valve 52 based on a control signal given from the CPU 100.

  The pump 51, the valve 52, the pump drive circuit 53, and the valve drive circuit 54 constitute an adjustment mechanism 50 for adjusting the cuff pressure. The device for adjusting the cuff pressure is not limited to these.

  The data input / output unit 46 reads and writes programs and data from, for example, a removable recording medium 132. In addition, the data input / output unit 46 may be able to transmit and receive programs and data from an external computer (not shown) via a communication line.

  Although the cuff 20 includes the air bladder 21, the fluid supplied to the cuff 20 is not limited to air, and may be a liquid or a gel, for example. Or it is not limited to fluid, Uniform microparticles, such as a microbead, may be sufficient.

  When the sphygmomanometer 1 measures blood pressure by the microphone method, the sphygmomanometer 1 receives a sound sensor 72 such as a microphone and a Korotkoff sound detection circuit 74 for receiving a signal from the sound sensor 72 and detecting Korotkoff sound. May be further provided. The sound sensor 72 is built in the cuff 20, and the Korotkoff sound detection circuit 74 is built in the main body 10. The Korotkoff sound detected by the Korotkoff sound detection circuit 74 is output to the CPU 100.

  In the present embodiment, in order to calculate the blood pressure by the oscillometric method, the measurement device 70 for the microphone method including the sound sensor 72 and the Korotkoff sound detection circuit 74 in FIG. Make it not exist.

(About functional configuration)
FIG. 3 is a functional block diagram showing a functional configuration of the sphygmomanometer 1 according to the embodiment of the present invention.

  Referring to FIG. 3, CPU 100 includes a pressurization control unit 102, a blood pressure estimation unit 104, a section determination unit 106, a decompression control unit 108, and a blood pressure calculation unit 110. In FIG. 3, only peripheral hardware that directly transmits and receives signals and data to and from these functional blocks is shown for ease of explanation.

  The pressurization control unit 102 controls the pump drive circuit 53 and the valve drive circuit 54 to perform pressurization control of the pressure in the cuff 20 up to a specific pressure value.

  The “specific pressure value” may be a predetermined value (for example, 200 mmHg) or higher by a predetermined value (for example, 40 mmHg) than the maximum blood pressure (maximum blood pressure equivalent value) estimated by the blood pressure estimation unit 104 described later. It may be a value. Alternatively, pressurization may be continued while the user (measured person) continues to press the measurement switch 41B. In this case, the specific pressure value is a cuff pressure at the time when the pressing of the measurement switch 41B is released. There may be. In the present embodiment, it is assumed that the specific pressure value is a predetermined value “PC1”.

  The pressurization control unit 102 pressurizes at a predetermined speed, that is, a constant speed. The amount of pressure change per unit time during pressurization is greater than the amount of pressure change per unit time during decompression. This is for shortening one blood pressure measurement time and reducing the discomfort of the measurement subject due to the measurement site compression.

  The blood pressure estimation unit 104 estimates (calculates) the maximum blood pressure, the minimum blood pressure, and the pulse rate by applying a predetermined algorithm during pressurization. The estimation of blood pressure and pulse rate during pressurization has been conventionally performed, and the method is not particularly limited. In the present embodiment, the blood pressure estimation method may be the same as the blood pressure calculation method described above with reference to FIG.

  The reason for “estimating” the maximum blood pressure and the minimum blood pressure at the time of pressurization is as follows. In the decompression measurement method, the cuff pressure needs to be increased to the maximum blood pressure or higher as quickly as possible. For this reason, the number of pulse wave amplitudes obtained during pressurization is very small, and only about 2 to 3 can be obtained, so accurate blood pressure measurement is impossible.

  As described above, the maximum blood pressure, the minimum blood pressure, and the pulse rate estimated by the blood pressure estimation unit 104 are referred to as a maximum blood pressure equivalent value, a minimum blood pressure equivalent value, and a pulse rate equivalent value, respectively.

  The section determining unit 106 determines a pressure section (hereinafter referred to as a “low-speed decompression section”) at which pressure is reduced at a low speed based on the maximum blood pressure equivalent value and the minimum blood pressure equivalent value estimated by the blood pressure estimation unit 104. More specifically, a predetermined interval before and after the maximum blood pressure equivalent value (for example, 5 mmHg) and a predetermined interval before and after the minimum blood pressure equivalent value (for example, 5 mmHg) are determined as the low-speed decompression interval.

  When the cuff pressure reaches a specific pressure value, the pressure reduction control unit 108 controls the valve driving circuit 54 to perform pressure reduction control of the cuff pressure. The depressurization control unit 108 decelerates the low-speed depressurization section determined by the section determination unit 106 at the first speed, and the second depressurization section other than the low-speed depressurization section in the depressurization control section is faster than the first speed. Depressurize at a rate of.

  Here, the “depressurization control section” represents a section starting from the specific pressure value and ending at the end of the minimum blood pressure or less. The end point of the decompression control section may be a predetermined value (for example, 0 mmHg), or may be the time when the minimum blood pressure is determined.

  The first speed and the second speed may each be a fixed value (for example, the first speed: 3 mmHg / sec, the second speed: 11 mmHg / sec). May be calculated based on the estimation result.

  In parallel with the pressure reduction control by the pressure reduction control unit 108, the blood pressure calculation unit 110 calculates the maximum blood pressure and the minimum blood pressure by the blood pressure calculation method described with reference to FIG. The blood pressure calculation unit 110 may further calculate the pulse rate by a known method. Each calculated value is displayed on the display unit 40 and stored as measurement data in the measurement result storage area 431 of the flash memory 43. An example of the data structure of the measurement result storage area 431 is shown in FIG.

  Referring to FIG. 4, records in which measurement values are associated with measurement dates are stored as measurement data M1 to Mm (where m = 1, 2, 3,...). Each measurement data includes systolic blood pressure data SBP indicating the maximum blood pressure, average blood pressure data MAP indicating the average blood pressure, minimum blood pressure data DBP indicating the minimum blood pressure, pulse rate data PLS indicating the pulse rate, and measurement date / time data T. It is. The measurement date / time data T is data for specifying the period in which the pulse wave information is detected, and is, for example, the current date / time (output data from the time measuring unit 45) when the measurement switch 41B is pressed. .

  Note that the measurement value and the measurement date and time need only be stored in association with each other, and are not limited to a storage format using a record. In the present embodiment, the average blood pressure data MAP may not be recorded as a measurement value.

  The operation of each functional block included in the CPU 100 may be realized by executing software stored in the memory unit 42, and at least one of these functional blocks is realized by hardware. May be.

<About operation>
FIG. 5 is a flowchart showing blood pressure measurement processing executed by sphygmomanometer 1 according to the embodiment of the present invention. The processing shown in the flowchart of FIG. 5 is stored in advance in the memory unit 42 as a program, and the blood pressure measurement processing function is realized by the CPU 100 reading and executing this program.

  Referring to FIG. 5, first, CPU 100 determines whether or not power switch 41A has been pressed (step S102). CPU 100 waits until power switch 41A is pressed (NO in step S102). When CPU 100 determines that power switch 41A has been pressed (YES in step S102), the process proceeds to step S104.

  In step S104, the CPU 100 performs an initialization process. Specifically, a predetermined area of the memory unit 42 is initialized, the air in the air bladder 21 is exhausted, and the pressure sensor 32 is corrected.

  When the measurement switch 41B is pressed, the pressurization control unit 102 pressurizes the cuff pressure (Step S106). Specifically, the pressurization control unit 102 performs control to close the valve 52 and gradually increase the cuff pressure to a predetermined value by the pump 51.

  In parallel with the pressurization control by the pressurization control unit 102, the blood pressure estimation unit 104 determines whether or not the blood pressure has been estimated (step S108). That is, it is determined whether all of the maximum blood pressure (maximum blood pressure equivalent value), the minimum blood pressure (minimum blood pressure equivalent value), and the pulse rate (pulse rate equivalent value) have been estimated. When it is determined that the blood pressure has not been estimated (NO in step S108), blood pressure estimating unit 104 estimates the blood pressure and the pulse rate (step S110). The blood pressure estimation process in step S110 will be described in detail later with reference to FIGS.

When the blood pressure estimation process ends, the process proceeds to step S114.
If it is determined in step S108 that blood pressure has been estimated (YES in step S108), the section determining unit 106 determines a low-speed decompression section based on the blood pressure estimation result (step S112). Specifically, the range from “maximum blood pressure equivalent value + predetermined pressure” to “maximum blood pressure equivalent value−predetermined pressure” is set as the first low-speed decompression section. A range from “minimum blood pressure equivalent value + predetermined pressure” to “minimum blood pressure equivalent value−predetermined pressure” is set as the second low-speed decompression section.

  Thus, in other sections, i) from a specific pressure value to “maximum blood pressure equivalent value + predetermined pressure”, ii) from “maximum blood pressure equivalent value−predetermined pressure” to “minimum blood pressure equivalent value + predetermined pressure”, And iii) A predetermined value (for example, 0 mmHg) from “minimum blood pressure equivalent value—predetermined pressure” is determined as a pressure section (hereinafter referred to as “high-speed decompression section”) for reducing the cuff pressure at a higher speed than the low-speed decompression section. In the present embodiment, the “predetermined pressure” is, for example, 5 mmHg.

  The section determination unit 106 may calculate a pressure range based on each blood pressure equivalent value according to the pulse pressure value at the time of blood pressure estimation (maximum blood pressure equivalent value−minimum blood pressure equivalent value). In this case, for example, a data table in which the pulse pressure and the pressure width are associated in advance is stored in the memory unit 42. Then, the section determination unit 106 reads out the pressure width associated with the difference value (that is, the pulse pressure) between the maximum blood pressure equivalent value and the minimum blood pressure equivalent value estimated by the blood pressure estimation unit 104, so that each pressure section Can be determined.

When the low-speed decompression section is determined, the process proceeds to step S114.
In step S114, it is determined whether or not the cuff pressure is equal to or higher than PC1. Until the cuff pressure reaches PC1, the processing of steps S106 to S112 is repeated. Note that once the low-pressure decompression section determination process (S112) is performed, it does not have to be executed after the next time.

  If it is determined in step S114 that the cuff pressure is equal to or higher than PC1 (“≧ predetermined pressure” in step S114), the process proceeds to step S115.

  In step S115, the pressure reduction control unit 108 calculates the pressure reduction speed in each pressure section. Specifically, for example, the decompression speed is calculated by the following equation (1).

  Where Pc: pressure difference in the speed calculation section, E_PLS: pulse rate estimated during pressurization, n: pulse wave number to be secured during decompression.

  By adjusting the pulse wave number (n) to be secured during decompression, the decompression speed can be changed. In the present embodiment, the pressure difference in each low-speed decompression section is 10 mmHg. Here, for example, a pulse wave of 5 beats is secured in the low-speed decompression section. On the other hand, for example, a 3-beat pulse wave is secured in the high-speed decompression section of ii). In that case, the speed Va in the low-speed decompression section and the speed Vb in the high-speed decompression section are calculated by the following equations (2) and (3), respectively.

  The speeds of the other high-speed decompression sections i) and iii) may also be the speeds calculated by the equation (3). Note that the pulse wave number to be ensured in the high-speed decompression section may be calculated according to the magnitude of the pulse pressure (maximum blood pressure equivalent value−minimum blood pressure equivalent value).

  Conventionally, it was considered that there should be a pulse wave of 5 beats between pulse pressures (usually about 30 to 80 mmHg), but in this embodiment, in the section (low pressure decompression section) with a pressure difference of 10 mmHg, Since a pulse wave of 5 beats is secured for each, blood pressure calculation accuracy can be increased. Further, it is sufficient to secure a pulse wave of 3 beats during the high-speed decompression section of ii) (usually a pressure difference of about 20 to 70 mmHg). Therefore, the high-speed decompression section decompresses at a speed faster than the conventional constant decompression speed. In this way, by reducing the speed only in a section where a sufficient number of pulse waves is required, it is possible to shorten the conventional measurement time (time required for decompression) as a result.

  In FIG. 5, the depressurization rate is calculated after the pressurization process is finished. However, the depressurization rate may be calculated during pressurization (for example, after the section is determined in step S112).

  When the process of step S115 is completed, the pressure reduction control unit 108 stops the pump 51, controls the opening amount of the valve 52, and gradually reduces the cuff pressure (step S116). The cuff pressure reduction control in the present embodiment will be described in detail later with reference to FIGS. 9 and 10.

  In parallel with the cuff pressure reduction control, the blood pressure calculation unit 110 executes a blood pressure calculation process (step S118). In the present embodiment, for example, the maximum blood pressure and the minimum blood pressure are calculated by the blood pressure calculation method described with reference to FIG. Moreover, the blood pressure calculation unit 110 calculates the pulse rate. These detailed calculation methods will be described later.

  Next, it is determined whether or not blood pressure (maximum blood pressure and minimum blood pressure) has been determined (step S120). Until the blood pressure is determined (NO in step S120), the cuff pressure reduction control and the blood pressure calculation process are repeated.

  When the blood pressure is determined (YES in step S120), the decompression control unit 108 controls the valve drive circuit 54 to completely open the valve 52 and exhaust the air (step S122).

  CPU 100 displays the determined blood pressure value (maximum blood pressure and minimum blood pressure) and the pulse rate on display unit 40 (step S124). An example of the screen displayed in step S124 is shown in FIG.

  Referring to FIG. 6, measurement date and time is displayed in area 401 of display unit 40. In regions 402, 403, and 404, the systolic blood pressure, the diastolic blood pressure, and the pulse rate calculated in the blood pressure calculation process (step S118) are displayed, respectively.

  Further, the CPU 100 associates the determined blood pressure value and pulse rate with the date and time and records them in the measurement result storage area 431 of the flash memory 43 (step S126).

This is the end of the blood pressure measurement process.
In this embodiment, the blood pressure calculation process is executed in real time. However, based on the pulse wave information recorded in the internal memory after the cuff pressure is reduced to a predetermined value (for example, 0 mmHg). The blood pressure may be calculated.

  Next, blood pressure estimation processing (step S110), pressure reduction control (step S116), and blood pressure calculation processing (step S118) in the present embodiment will be described in detail.

(Blood pressure estimation process)
The blood pressure estimation process will be described with reference to FIGS.

  FIG. 7 is a flowchart showing blood pressure estimation processing in the embodiment of the present invention. FIG. 8 is a diagram for explaining blood pressure estimation processing. FIG. 8A shows the cuff pressure (unit: mmHg) gradually increased along the time axis, and FIG. 8B is superimposed on the cuff pressure along the same time axis. The pulse wave amplitude (unit: mmHg) is partially shown.

  Referring to FIG. 7, blood pressure estimation unit 104 extracts the pulse wave amplitude superimposed on the cuff pressure based on the output from oscillation circuit 33 (step S202). Subsequently, the blood pressure estimation unit 104 determines whether or not the maximum value of the pulse wave amplitude has been detected (step S204). If it is determined that the maximum value of the pulse wave amplitude has not been detected (NO in step S204), the process returns to the main routine.

  When it is determined that the maximum value of the pulse wave amplitude has been detected (YES in step S204), the cuff pressure corresponding to the maximum value of the pulse wave amplitude (“E_AMAX” in FIG. 8) is calculated as an average blood pressure equivalent value (in FIG. 8). "E_MAP") (step S206).

  The blood pressure estimation unit 104 calculates threshold values ETH_DIA and ETH_SYS (step S208). Specifically, a value obtained by multiplying the maximum point E_AMAX by a predetermined constant (for example, 0.5) is defined as a threshold value ETH_SYS, and a value obtained by multiplying the maximum point E_AMAX by a predetermined constant (for example, 0.7) is defined as a threshold value ETH_DIA.

  Next, the blood pressure estimation unit 104 calculates a cuff pressure lower than the average blood pressure equivalent value (E_MAP) corresponding to the point where the envelope 610 of the pulse wave amplitude and the threshold value ETH_DIA intersect with each other (8 “E_DIA” in the figure). ]) (Step S210). The determined minimum blood pressure equivalent value is recorded in the internal memory of the CPU 100, for example.

  In addition, when the cuff pressure increases higher than the average blood pressure equivalent value (E_MAP), the blood pressure estimation unit 104 extracts a point where the envelope 610 of the pulse wave amplitude and the threshold value ETH_SYS intersect. Is determined as the maximum blood pressure equivalent value (“E_SYS” in FIG. 8) (step S212). The determined systolic blood pressure equivalent value is recorded in the internal memory of the CPU 100, for example.

  Further, the blood pressure estimation unit 104 calculates a pulse rate equivalent value by a known method (step S214). When this process ends, the process returns to the main routine.

  In FIG. 7, for the sake of simplicity, the procedure is such that both the minimum blood pressure equivalent value and the maximum blood pressure equivalent value can be determined when the maximum value of the pulse wave amplitude is detected. At the time when the maximum value of the amplitude is detected, the maximum blood pressure equivalent value cannot be determined. When the processes after step S204 are executed for the second time or later, the processes of steps S204 to S210 may be skipped.

  Further, in the blood pressure estimation process during pressurization, since the number of detected pulse waves is small, the maximum blood pressure equivalent value and the minimum blood pressure equivalent value may be calculated after correcting the pulse wave amplitude (envelope 610). .

(Decompression control)
The cuff pressure reduction control in the present embodiment will be described in detail with reference to FIG. 9 and FIG.

FIG. 9 is a flowchart showing the pressure reduction control in the embodiment of the present invention.
Referring to FIG. 9, the decompression control unit 108 determines whether the cuff pressure is a high-speed decompression section or a low-speed decompression section (step S302). If it is determined that the cuff pressure is in the high-speed decompression section (“high-speed decompression section” in step S302), the decompression speed is set to a high speed (step S304). On the other hand, when it is determined that the cuff pressure is in the low speed decompression section (“low speed decompression section” in step S302), the decompression speed is set to low speed (step S306).

  Next, the decompression control unit 108 reduces the cuff pressure according to the set speed (step S308). That is, the depressurization control unit 108 performs the cuff pressure depressurization control at the speed Va calculated in step S115 during the low-speed depressurization section, and performs the cuff pressure depressurization control at the speed Vb calculated in step S115 during the high-speed depressurization section.

When the process of step S308 ends, the process returns to the main routine.
FIG. 10 is a diagram for explaining the pressure reduction control in the embodiment of the present invention. FIG. 10A shows the cuff pressure (unit: mmHg) gradually increased and decreased along the time axis, and FIG. 10B shows the cuff pressure along the same time axis. The pulse wave amplitude (unit: mmHg) superimposed on is partially shown.

  Referring to FIG. 10A, in the present embodiment, low-speed decompression section 502 near the systolic blood pressure and low-speed decompression section 504 near the systolic blood pressure are the high-speed decompression sections 501, 503, and 505 of i) to iii) above. The pressure is reduced at a lower speed. As a result, as shown in FIG. 10B, when the cuff pressure is in the sections 502 and 504 (time T2 to T3, T4 to T5), the number of pulse wave amplitudes extracted is in the other sections. More than a certain time (time T1-T2, T3-T4, T5-T6).

(Blood pressure calculation process)
The blood pressure calculation process in the present embodiment will be described with reference to FIG. 11 and FIG.

FIG. 11 is a flowchart showing blood pressure calculation processing in the embodiment of the present invention.
Referring to FIG. 11, blood pressure calculation unit 110 extracts the pulse wave amplitude superimposed on the cuff pressure based on the output from oscillation circuit 33 (step S402). Subsequently, the blood pressure calculation unit 110 determines whether or not the maximum value of the pulse wave amplitude has been detected (step S404). If it is determined that the maximum value of the pulse wave amplitude has not been detected (NO in step S404), the process returns to the main routine.

  If it is determined that the maximum value of the pulse wave amplitude has been detected (YES in step S404), the cuff pressure corresponding to the maximum value of the pulse wave amplitude is specified as the average blood pressure (step S406).

  In addition, the blood pressure calculation unit 110 calculates threshold values TH_DIA and TH_SYS (step S408). Specifically, a value obtained by multiplying the maximum point detected in step S404 by a predetermined constant (for example, 0.5) is set as a threshold TH_SYS, and a value obtained by multiplying the maximum point by a predetermined constant (for example, 0.7) is set. The threshold value is ETH_DIA.

  Next, the blood pressure calculation unit 110 determines the cuff pressure that is higher than the average blood pressure and that corresponds to the point at which the envelope 620 of the pulse wave amplitude and the threshold value TH_SYS intersect as the maximum blood pressure (step S410). The determined systolic blood pressure is recorded in the internal memory of the CPU 100, for example.

  In addition, the blood pressure calculation unit 110 determines the cuff pressure that is lower than the average blood pressure and that corresponds to the point where the envelope 620 of the pulse wave amplitude and the threshold value TH_DIA intersect with each other as the minimum blood pressure (step S412). The determined minimum blood pressure is recorded in the internal memory of the CPU 100, for example.

  Furthermore, the blood pressure calculation unit 110 calculates the pulse rate by a known method (step S414). When this process ends, the process returns to the main routine.

  In this way, by reducing the cuff pressure in the vicinity of the maximum blood pressure equivalent value and the minimum blood pressure equivalent value to low speed, the pulse wave amplitude information in the vicinity of each equivalent value, that is, in the vicinity of the threshold values TH_SYS and TH_DIA can be obtained densely. Thereby, the reliability of the parts 621 and 622 used for blood pressure determination in the envelope 620 of the pulse wave amplitude is increased. Therefore, it is not necessary to correct the pulse wave amplitude information (envelope) as in the prior art. As a result, no error due to correction occurs, so that the accuracy of blood pressure calculation can be improved. Furthermore, by setting the other pressure section (high-speed decompression section) faster than the conventional constant decompression speed, the overall measurement time can be made shorter than before. That is, the times T0 to T6 in FIG. 10 can be made shorter than the times T0 to TE in FIG.

  As a result, according to the present embodiment, the systolic blood pressure and the diastolic blood pressure can be measured in a short time and with high accuracy.

  In the present embodiment, the vicinity of both the systolic blood pressure and the diastolic blood pressure is reduced at low speed. However, at least one of the blood pressure values may be reduced at a low speed. In this case, the blood pressure estimation unit 104 only has to estimate one of the maximum blood pressure and the minimum blood pressure, and the section determination unit 106 determines only the pressure section near the estimated one blood pressure value as the low speed deceleration section. do it.

<Modification 1>
In the above embodiment, the systolic blood pressure and the diastolic blood pressure are estimated at the time of pressurization, and the vicinity of these pressure values is set as the low-speed decompression section. As described above, according to the oscillometric method, the maximum value of the pulse wave amplitude corresponding to the average blood pressure is detected, and the maximum blood pressure and the minimum blood pressure are calculated and estimated based on the detected maximum value. Therefore, it is important to accurately detect the maximum value of the pulse wave amplitude. Therefore, it is preferable that the number of pulse wave amplitudes around the average blood pressure is also large.

  In the first modification of the present embodiment, the average blood pressure is also estimated at the time of pressurization, and the vicinity of the average blood pressure equivalent value is also set as the low-speed decompression section. Note that the configuration and basic operation of the sphygmomanometer in the present modification are the same as those in the above-described embodiment, and will be described using the reference numerals in FIGS.

Only differences from the above embodiment will be described below.
In this modification, an average blood pressure equivalent value is estimated in the blood pressure estimation process (step S110 in FIG. 5, FIG. 7). The specification of the average blood pressure equivalent value in step S206 in FIG. 7 corresponds to the estimation of the average blood pressure equivalent value.

  In step S112 of FIG. 5, the section determination unit 106 further determines a section from “average blood pressure equivalent value + predetermined pressure” to “average blood pressure equivalent value−predetermined pressure” as the third low-speed decompression section. This predetermined pressure may also be 5 mmHg, for example. Then, a part of the pressure section (from “maximum blood pressure equivalent value−predetermined pressure” to “minimum blood pressure equivalent value + predetermined pressure”) that is the high-speed decompression section of ii) in the above embodiment becomes the low-speed decompression section. .

  The decompression control unit 108 performs cuff pressure decompression control according to the determination result by the section determination unit 106. The pressure reduction control (step S116 in FIG. 5, FIG. 9) in this modification is as shown in FIG.

  FIG. 12 is a diagram for explaining the pressure reduction control in the first modification of the embodiment of the present invention. FIG. 12A shows the cuff pressure (unit: mmHg) gradually increased and decreased along the time axis, and FIG. 12B shows the cuff pressure along the same time axis. The pulse wave amplitude (unit: mmHg) superimposed on is partially shown.

  Referring to FIG. 12A, in the present embodiment, low-speed decompression section 502 near the maximum blood pressure, low-speed decompression section 503b near the average blood pressure, and low-speed decompression section 504 near the minimum blood pressure are slower than the other sections. At reduced pressure. That is, the pressure section 501 of i), the pressure section 505 of iii), the section 503a from “maximum blood pressure equivalent value—predetermined pressure” to “average blood pressure equivalent value + predetermined pressure”, “average blood pressure equivalent value—predetermined pressure” ”To“ minimum blood pressure equivalent value + predetermined pressure ”is a high-speed decompression section.

  Then, as shown in FIG. 12B, when the cuff pressure is in the pressure sections 502, 503b and 504 (time T2 to T3, T4a to T5a, T6a to T7a), the number of pulse wave amplitudes extracted is More than when it is in other sections (time T1-T2, T3-T4a, T5a-T6a, T7a-T8a).

  As a result, the detection accuracy of the maximum value of the pulse wave amplitude can be increased in the blood pressure calculation process (step S118 in FIG. 5 and FIG. 11) (step S404 in FIG. 11). Accordingly, the reliability of the systolic blood pressure and the diastolic blood pressure calculated on the basis of the maximum value of the pulse wave amplitude can be improved as compared with the above embodiment.

<Modification 2>
In the above-described embodiment and Modification 1, each blood pressure equivalent value serving as a reference value for determining the low-speed decompression section is estimated during pressurization. In the second modification of the present embodiment, each blood pressure equivalent value is a value based on past measurement data.

  The configuration and basic operation of the sphygmomanometer in the present modification are the same as those in the above embodiment, and will be described using the reference numerals in FIGS.

Only differences from the embodiment will be described below.
FIG. 13 is a functional block diagram of the sphygmomanometer 1 according to the second modification of the embodiment of the present invention.

  Referring to FIG. 13, CPU 100 does not include blood pressure estimation unit 104 shown in FIG. The section determination unit 106a determines a low-speed decompression section based on the measurement data stored in the measurement result storage area 431 (FIG. 4) of the flash memory 43. Specifically, for example, the systolic blood pressure data SBP and the diastolic blood pressure data DBP of the latest measurement data of the measured person become the systolic blood pressure equivalent value and the diastolic blood pressure equivalent value, respectively. Alternatively, the section determination unit 106a may set the average values of the highest blood pressure data SBP and the lowest blood pressure data DBP of the measurement subject's latest multiple times (for example, five times) as the highest blood pressure equivalent value and the lowest blood pressure equivalent value. In the latter case, the section determination unit 106a reads the maximum blood pressure data SBP and the minimum blood pressure data DBP that have been measured a plurality of times (for example, five times) closest to the measurement subject, and calculates an average value for each type (maximum, minimum). Shall.

  The blood pressure measurement process in the present modification is the same as the above embodiment except that the process related to blood pressure estimation (steps S108 and S110 in FIG. 5) is not required and the section determination process (step S112 in FIG. 5) is different.

  As described above, even if the blood pressure value estimated in the series of blood pressure measurement processes is not used, the low-speed decompression section can be appropriately determined by using the measurement data of the measurement subject.

  When the two speeds in the decompression control section are calculated using the pulse rate equivalent value, the pulse rate equivalent value may also be a value based on the pulse rate data PLS included in the measurement data.

  When using a past stored value as in this modification, the blood pressure may be calculated in the process of increasing the cuff pressure. In other words, a pressure section for pressurizing at a low speed and a pressure section for pressurizing at a high speed may be determined, and pressurization control may be performed based on the determined pressure section.

  Or you may combine this modification and the previous modification 1. FIG. In this case, the average blood pressure equivalent value may also be a value based on the average blood pressure data MAP included in the measurement data.

<Modification 3>
In the second modification, the low-speed decompression section is determined based on the measurement data stored inside, but may be determined based on the input from the outside. In Modification 3, the input of the maximum blood pressure equivalent value and the minimum blood pressure equivalent value is accepted from the outside.

  The configuration and basic operation of the sphygmomanometer in the present modification are the same as those in the above embodiment, and will be described using the reference numerals in FIGS.

  Since the operation of the sphygmomanometer 1 in the present modification is similar to that of the second modification, only differences from the second modification of the embodiment will be described below.

FIG. 14 is a functional block diagram of the sphygmomanometer 1 according to the third modification of the embodiment of the present invention.
In the present modification, the section determination unit 106b performs low-speed decompression based on the systolic blood pressure and the diastolic blood pressure (and average blood pressure and pulse rate) input from the user (typically the person to be measured) via the operation unit 41. Determine the interval. That is, in this modification, various blood pressure equivalent values and pulse rate equivalent values are values input by the user, for example.

  Alternatively, the section determining unit 106b may determine a low-speed decompression section based on data obtained from the data input / output unit 46. For example, the data input / output unit 46 reads the systolic blood pressure data and the diastolic blood pressure data (and average blood pressure data and pulse rate data) recorded on the removable recording medium 132, and outputs them to the section determining unit 106b. In this case, various blood pressure equivalent values and pulse rate equivalent values are values read from the recording medium 132. It is assumed that each data recorded on the recording medium 132 is past measurement data of the measurement subject.

  Alternatively, the data input / output unit 46 receives systolic blood pressure data and diastolic blood pressure data (and average blood pressure data, pulse rate data) from an external computer (not shown) via a communication line (not shown), and It outputs to the determination part 106b. In this case, various blood pressure equivalent values and pulse rate equivalent values are values received from an external computer. In addition, each data preserve | saved at the external computer shall be a measurement person's past measurement data.

  As described above, the low-speed decompression section can be appropriately determined based on the input value from the outside.

<Modification 4>
In the above embodiment and each modification, blood pressure calculation according to the oscillometric method has been described, but the present invention can also be applied to the case where blood pressure is calculated according to the microphone method.

  The configuration and basic operation of the sphygmomanometer in the present modification are also the same as those in the above embodiment, and will be described using the reference numerals in FIGS. Only differences from the above embodiment will be described below.

  When calculating blood pressure according to the microphone method, the blood pressure calculation unit 110 determines the maximum blood pressure and the minimum blood pressure based on the output from the Korotkoff sound detection circuit 74. Specifically, the cuff pressure when the Korotkoff sound starts to occur is determined as the maximum blood pressure, and the cuff pressure when the Korotkoff sound disappears (or weakly) is determined as the minimum blood pressure.

  Also in this case, since the pressure interval in which the maximum blood pressure and the minimum blood pressure are expected to be detected is reduced at a lower speed than the other pressure intervals, the maximum blood pressure and the minimum blood pressure can be accurately determined.

  In addition, since the driving sound of the pump 51 is generated when the cuff pressure is increased, it is difficult to estimate the blood pressure by the microphone method when the cuff pressure is increased. Therefore, when calculating (determining) blood pressure by the microphone method, it is preferable to combine with Modification 2 or Modification 3. Alternatively, the oscillometric method may be used only for blood pressure estimation.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is an external perspective view of a sphygmomanometer according to an embodiment of the present invention. It is a block diagram showing the hardware constitutions of the blood pressure meter which concerns on embodiment of this invention. It is a functional block diagram which shows the function structure of the blood pressure meter which concerns on embodiment of this invention. It is a figure which shows the example of a data structure of a measurement result storage area. It is a flowchart which shows the blood-pressure measurement process which the blood pressure meter in embodiment of this invention performs. It is a figure which shows an example of the screen displayed by step S124 of FIG. It is a flowchart which shows the blood-pressure estimation process in embodiment of this invention. It is a figure for demonstrating the blood-pressure estimation process in embodiment of this invention. It is a flowchart which shows the pressure reduction control in embodiment of this invention. It is a figure for demonstrating pressure reduction control in embodiment of this invention. It is a flowchart which shows the blood-pressure calculation process in embodiment of this invention. It is a figure for demonstrating pressure reduction control in the modification 1 of embodiment of this invention. It is a functional block diagram of the sphygmomanometer in the modification 2 of embodiment of this invention. It is a functional block diagram of the sphygmomanometer in the modification 3 of embodiment of this invention. It is a figure for demonstrating the general blood-pressure measuring method by an oscillometric method.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Blood pressure monitor, 10 Main-body part, 20 cuff, 21 Air bag, 30 Air system, 31 Air tube, 32 Pressure sensor, 33 Oscillator circuit, 40 Display part, 41 Operation part, 41A Power switch, 41B Measurement switch, 41C Stop switch , 41D memory switch, 42 memory section, 43 flash memory, 44 power supply, 45 clocking section, 46 data input / output section, 50 adjustment mechanism, 51 pump, 52 valve, 53 pump drive circuit, 54 valve drive circuit, 72 sound sensor, 74 Korotkoff sound detection circuit, 100 CPU, 102 pressurization control unit, 104 blood pressure estimation unit, 106, 106a, 106b section determination unit, 108 decompression control unit, 110 blood pressure calculation unit, 132 recording medium, 431 measurement result storage area, 600 , 610, 620 Envelope.

Claims (12)

A cuff for wrapping around a predetermined measurement site of the subject,
Adjusting means for adjusting the pressure in the cuff by pressurization and decompression;
Pressure detecting means for detecting the pressure in the cuff;
Control means,
The control means includes
Pressurizing control means for controlling the adjusting means to perform control for pressurizing the pressure in the cuff to a specific pressure value;
Pressure reduction control means for controlling the adjustment means to reduce the pressure in the cuff when the pressure in the cuff reaches the specific pressure value;
The depressurization control means performs at least one of a first pressure interval including a value corresponding to the systolic blood pressure and a second pressure interval including a value corresponding to the diastolic blood pressure on the first pressure change per unit time. Depressurizing by an amount, depressurizing a third pressure section with a second pressure change amount greater than the first pressure change amount,
The decompression control means includes
Means for calculating the first pressure change amount based on a pulse rate equivalent value and a predetermined first calculation formula;
Means for calculating the second pressure change amount based on the pulse rate equivalent value, the systolic blood pressure equivalent value, the diastolic blood pressure equivalent value, and a predetermined second calculation formula ;
The control means includes
An electronic sphygmomanometer, further comprising calculation means for calculating a blood pressure value of the measurement subject based on an output from the pressure detection means during pressure reduction by the pressure reduction control means. The control means further includes a determination means for determining the first and second pressure sections,
The determining means determines a predetermined pressure width before and after the systolic blood pressure equivalent value as the first pressure interval, and determines the predetermined pressure width before and after the diastolic blood pressure equivalent value as the second pressure interval. The electronic blood pressure monitor according to claim 1.   3. The electron according to claim 1, wherein the third pressure section represents a section excluding the first and / or second pressure section in a decompression control section starting from the specific pressure value. Sphygmomanometer. The depressurization control means further depressurizes the fourth pressure section including the average blood pressure equivalent value by the first pressure change amount,
It said third pressure zone, of the pressure reduction control section that starts the specific pressure value, representing the first, section excluding the second and / or fourth pressure section of claim 1-3 The electronic blood pressure monitor according to any one of the above. The control means further includes estimation means for estimating the maximum blood pressure equivalent value and the minimum blood pressure equivalent value based on an output from the pressure detection means during pressurization by the pressurization control means. Item 5. The electronic blood pressure monitor according to any one of Items 1 to 4 . It said estimating means further estimates at least one of the pulse rate corresponding value and the average blood pressure value corresponding electronic blood pressure meter according to claim 5. Sound detection means for detecting Korotkoff sound emitted from the artery of the measurement site compressed by the cuff;
Said calculation means, based on the output from the pressure detecting means and the sound detecting means, said calculating a blood pressure value of the subject, the electronic sphygmomanometer according to any one of claims 1-6. A cuff for wrapping around a predetermined measurement site of the subject,
Adjusting means for adjusting the pressure in the cuff by pressurization and decompression;
Pressure detecting means for detecting a pressure signal representative of the pressure in the cuff;
Control means,
The control means includes a pressurization control means for controlling the adjustment means to pressurize the pressure in the cuff to a specific pressure value,
The pressurization control means sets at least one of a first pressure interval including a maximum blood pressure equivalent value of the subject and a second pressure interval including a minimum blood pressure equivalent value to a first pressure per unit time. Pressurizing with a change amount, pressurizing the third pressure section with a second pressure change amount larger than the first pressure change amount,
The pressure control means includes
Means for calculating the first pressure change amount based on a pulse rate equivalent value and a predetermined first calculation formula;
Means for calculating the second pressure change amount based on the pulse rate equivalent value, the systolic blood pressure equivalent value, the diastolic blood pressure equivalent value, and a predetermined second calculation formula;
The control means includes
During pressurization by said pressurization control means, based on the output from the pressure detecting means, further saw including a calculating means for calculating the blood pressure value of the subject,
Storage means for storing the blood pressure value calculated by the calculation means as measurement data;
The maximum blood pressure equivalent value, the minimum blood pressure equivalent value, and the pulse rate equivalent value are values based on the measurement data stored in the storage means or values received by external input . E Bei memory means for storing the blood pressure value calculated by said calculating means as measurement data,
The systolic blood pressure value corresponding the minimum blood pressure equivalent value and the pulse rate corresponding value, the a the value based on measurement data stored in the storage means, the electronic sphygmomanometer according to any one of claims 1-4. Storage means for storing the blood pressure value calculated by the calculation means as measurement data;
The electronic sphygmomanometer according to claim 4, wherein the average blood pressure equivalent value is a value based on the measurement data stored in the storage unit. The externally systolic blood pressure value corresponding the accepting an input of the minimum blood pressure equivalent value and the pulse rate corresponding value, the electronic sphygmomanometer according to any one of claims 1-4. The electronic sphygmomanometer according to claim 4, wherein an input of the average blood pressure equivalent value is accepted from outside.

Images