JP6001683B2 - Blood pressure measurement device - Google Patents

Description

  The present invention relates to a blood pressure measurement device capable of evaluating a vascular endothelial function of a subject.

  Vascular endothelial dysfunction is a disorder that appears from the stage before the organic change of arteriosclerosis occurs, and is caused by factors such as increased LDL (bad cholesterol) in the blood, increased blood pressure, and increased oxidative stress. In general, when the vascular endothelial function decreases, the production of vasodilators such as NO (nitrogen monoxide) decreases, and the function of the blood vessel as an organ is impaired.

  In recent years, a flow-dependent dilation test (FMD) has attracted attention as a test for evaluating vascular endothelial function. The blood flow-dependent vasodilator test evaluates how much NO (nitrogen monoxide), a vasodilator, is released from the vascular endothelium by “shear stress” due to increased blood flow after the arm is clamped with a cuff. Is.

  Since how much NO (nitrogen monoxide) has been released can be determined by measuring how much the blood vessel clamped by the cuff has dilated after resumption of blood flow, The evaluation was performed by measuring the blood vessel diameter using an ultrasonic echo. Also, a dedicated compression device was used to tighten the blood vessel with the cuff.

JP 2009-219716 A

  However, the method using ultrasonic echoes for measuring the blood vessel diameter has a problem that the cost is high and the variation of the measurement value due to the measurer's procedure is large and the reproducibility is lacking. For this reason, it is desired to be able to evaluate the vascular endothelial function by a simpler method regardless of the measurer's procedure.

  In addition, if the blood pressure measurement can be performed together with the evaluation of the vascular endothelial function, the workload of the measurer can be reduced. For this reason, it is considered that more efficient measurement can be performed by using a blood pressure measurement device instead of using a dedicated compression device as a device for tightening a blood vessel with a cuff.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a blood pressure measurement device capable of realizing highly accurate vascular endothelial function evaluation by a simple method.

A blood pressure measurement device according to one aspect of the present invention is attached to a body surface of a site where a blood vessel is anastomosed with an artery and vein, and a first temperature detection unit that detects first temperature data, and the blood vessel is connected to the artery and vein A second part that is attached to the body surface upstream of the position where the first temperature detection unit is attached, and detects second temperature data. Together with a temperature detection unit, a pressurizing pump that pressurizes a cuff unit that compresses a portion upstream of the position where the second temperature detection unit is attached in the blood flow direction, and the first temperature detection unit A first pulse wave detection unit that is mounted and detects first pulse wave data; a second pulse wave detection unit that is mounted together with the second temperature detection unit and detects second pulse wave data; During the pressurization by the pressurization pump, the pressure of the part compressed by the cuff part is detected. A first calculating means for calculating a minimum blood pressure value and a maximum blood pressure value based on an output of the pressure sensor, and a second calculating means for calculating an evaluation value related to the vascular endothelial function, wherein the second calculating means Is the difference between the first temperature data and the second temperature data detected after the blood flow is resumed when the blood flow is resumed after being blocked by the cuff portion for a predetermined time. Means for calculating a first evaluation value related to the vascular endothelial function based on the value, each pulse wave included in the first pulse wave data detected after the blood flow is resumed, and the second pulse wave data Means for calculating a second evaluation value related to the vascular endothelial function based on a delay time that is a time difference between each corresponding pulse wave.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the blood-pressure measuring apparatus which can implement | achieve highly accurate vascular endothelial function evaluation by a simple method.

  Other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings. In the accompanying drawings, the same or similar components are denoted by the same reference numerals.

The accompanying drawings are included in the specification, constitute a part thereof, show an embodiment of the present invention, and are used to explain the principle of the present invention together with the description.
FIG. 1 is a diagram showing an external configuration of a blood pressure measurement device 100 according to the first embodiment of the present invention. FIG. 2 is a diagram illustrating a functional configuration of the blood pressure measurement device 100. FIG. 3 is a diagram illustrating an example of the temperature measured by the peripheral blood vessel measurement unit. FIG. 4 is a diagram illustrating a state in which blood pressure measurement processing and vascular endothelial function evaluation processing are executed using the blood pressure measurement device 100. FIG. 5 is a diagram showing a time change of an evaluation parameter used for calculating an evaluation value indicating a vascular endothelial function and a time change of pressure data used for calculating a blood pressure measurement value. FIG. 6A is a sequence diagram showing the flow of blood pressure measurement processing and vascular endothelial function evaluation processing. FIG. 6B is a sequence diagram illustrating the flow of blood pressure measurement processing and vascular endothelial function evaluation processing. FIG. 7 is a diagram illustrating a functional configuration of the blood pressure measurement device 700. FIG. 8 is a diagram illustrating an example of a pulse wave measured by the peripheral blood vessel measurement unit. FIG. 9 shows a time change of an evaluation parameter used for calculating an evaluation value indicating vascular endothelial function, a time change of pressure data used for calculating a blood pressure measurement value, and a time change of pulse wave data. FIG. FIG. 10A is a sequence diagram showing the flow of blood pressure measurement processing and vascular endothelial function evaluation processing. FIG. 10B is a sequence diagram showing the flow of blood pressure measurement processing and vascular endothelial function evaluation processing. FIG. 11 shows the measurement mode.

  First, an outline of each embodiment will be described. Of the following embodiments, the first embodiment focuses on the correlation between the degree of dilation of the blood vessel and the peripheral blood circulation in measuring how much the blood vessel clamped by the cuff portion has expanded after the blood flow is resumed. And measuring the temperature of the peripheral part after resumption of blood flow of the blood vessel clamped by the cuff part and the temperature of the peripheral part in a stable state not clamped by the cuff part, thereby evaluating the vascular endothelial function. I decided to do it.

  In the second embodiment, in measuring how much the blood vessel clamped by the cuff portion has expanded after resumption of blood flow, attention is paid to the correlation between the degree of vessel expansion and the transmission speed of the pulse wave. To evaluate vascular endothelial function by measuring the pulse wave transmission speed after resumption of blood flow in the blood vessel tightened by the cuff and the pulse wave transmission speed in a stable state not tightened by the cuff part It was.

  In this way, by replacing the degree of vascular dilation with the temperature or pulse wave transmission rate by peripheral blood circulation, it is simpler than the conventional method of directly measuring the vascular diameter with ultrasonic echoes. Moreover, it has become possible to achieve highly accurate evaluation of vascular endothelial function.

  In each of the following embodiments, the blood pressure measuring device is used instead of a dedicated compression device as a device for tightening the blood vessel with the cuff part. Further, the blood pressure of the subject is measured at the time of pressurization when the blood vessel of the upper arm is pressed to evaluate the vascular endothelial function. This makes it possible to efficiently perform vascular endothelial function evaluation and blood pressure measurement. Furthermore, in the case of measuring the degree of expansion of the blood vessel by replacing it with the transmission speed of the pulse wave, it is configured to monitor the presence or absence of the pulse wave during pressurization and stop the pressurization when the pulse wave is no longer detected It was. This makes it possible to avoid a situation in which the subject's blood vessel is compressed more than necessary.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiment described below is a preferred specific example of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise stated, the present invention is not limited to these embodiments.

[First Embodiment]
<1. Appearance configuration of blood pressure measurement device>
FIG. 1 is a diagram showing an external configuration of a blood pressure measurement device 100 according to the first embodiment of the present invention. As shown in FIG. 1, the blood pressure measurement device 100 includes a main body 110, a remote control unit 120 and a peripheral blood vessel measurement unit 130 that are detachably provided on the main body 110.

  The main body portion 110 is configured by a hollow housing so that the subject's arm can be inserted, and a cuff portion 111 for compressing the upper arm portion of the inserted subject's arm is arranged in the hollow portion. Has been. Further, a main body side operation unit 112 for inputting various instructions to the blood pressure measurement device 100 is provided.

  In addition to the calculated blood pressure value (maximum blood pressure value, minimum blood pressure value) and the evaluation value of the vascular endothelial function, the remote control unit 120 is provided with a display unit 121 that displays the internal state of the blood pressure measurement device 100. In addition, a remote control side operation unit 122 for inputting various instructions to the blood pressure measurement device 100 via the remote control unit 120 is disposed (hereinafter, the main body side operation unit 112 and the remote control side operation unit 122 are collectively referred to). And called the operation unit).

  The peripheral blood vessel measurement unit 130 is configured to be detachably connected to the main body unit 110 along a dotted arrow. The peripheral blood vessel measurement unit 130 is provided with a connector unit 131 for electrical connection to the main body unit 110. Also, a reference body temperature detector 133 that is attached to the wrist portion of the subject and detects the temperature of the body surface of the wrist portion, and a temperature of the body surface of the fingertip portion (constriction of blood vessels) is attached to the fingertip portion of the subject. -The temperature of the adjustment body temperature detection unit 134 that detects heat loss / diffusion through expansion and the temperature of the body temperature adjustment), the detection of temperature by the reference body temperature detection unit 133 and the adjustment body temperature detection unit 134 is controlled and detected. A detection control unit 132 that transmits temperature data to the main body unit 110 is arranged.

  The connector unit 131 and the detection control unit 132 are connected by a wiring 135, and the detection control unit 132, the reference body temperature detection unit 133, and the adjusted body temperature detection unit 134 are connected by a wiring 136.

<2. Functional Configuration of Blood Pressure Measuring Device 100>
Next, the functional configuration of the blood pressure measurement device 100 will be described. FIG. 2 is a diagram illustrating a functional configuration of the blood pressure measurement device 100.

  As shown in FIG. 2, the main body 110 and the remote controller 120 of the blood pressure measurement device 100 include a power supply unit 201 that supplies power, operation units 112 and 122 for inputting various instructions, blood pressure values and internal states. Is displayed, and a control unit 220 that controls the entire blood pressure measurement device 100 is provided.

  The control unit 220 stores a program that functions as the blood pressure measurement unit 221 and a program that functions as the vascular endothelial function evaluation unit 222 in a non-volatile memory by being executed by a CPU (not shown). And Further, triggered by an instruction from the operation units 112 and 122, the program is read into a RAM (not shown) that functions as a work area, and is executed by the CPU. Measurement data (temperature data in this embodiment) 224 is stored.

  The blood pressure measurement device 100 further includes a pressurizing pump 203 that pressurizes the cuff unit 111 by sending air to the cuff unit 111, an exhaust valve 204 that rapidly discharges air in the cuff unit 111, and a pressure in the cuff unit 111. And a filter / amplifier unit 205 that filters and amplifies the pressure signal detected by the pressure sensor 207 and transmits it to the control unit 220 as pressure data. Furthermore, a constant speed exhaust valve 208 for discharging the air in the cuff part 111 at a constant speed is provided.

  The control unit 220 is connected to a connector unit 202 for connecting to the peripheral blood vessel measurement unit 130.

  On the other hand, the peripheral blood vessel measurement unit 130 of the blood pressure measurement device 100 includes a reference body temperature detection unit 133 attached to the wrist portion of the subject, an adjustment body temperature detection unit 134 attached to the fingertip portion, and a reference body temperature detection unit 133. And a detection control unit 132 that transmits temperature data detected in each of the adjusted body temperature detection units 134 to the main body 110.

  The reference body temperature detector 133 and the adjusted body temperature detector 134 are provided with temperature detectors 261 and 271 that measure the temperatures of the wrist portion and the fingertip portion of the subject, respectively. The temperature detection units 261 and 271 are configured to output an analog signal substantially linearly with respect to a temperature change. For example, the temperature of a semiconductor type having a temperature resolution of 0.05 ° C. between 35 ° C. and 42 ° C. Sensors and thermistors shall be used. Processing of the body temperature signal detected by the temperature detection units (for example, thermistors) 261 and 271 is executed by the calculation control units 251 and 252. The body temperature signal processed in the arithmetic control units 251 and 252 is input to the control unit 250 and transmitted to the main body unit 110 via the connector unit 131 as temperature data.

<3. Explanation of temperature data>
Next, temperature data (wrist part) and temperature data (fingertip part) detected by the peripheral blood vessel measurement unit 130 and transmitted to the main body 110 will be described. FIG. 3 is a diagram illustrating an example of temperature data detected by the peripheral blood vessel measurement unit 130.

  In general, the body temperature control of the human body is realized by two functions of a core and a shell, and the core is a central deep part of the body and is adjusted to about 37 ° C. On the other hand, the shell largely depends on the environmental temperature and peripheral blood circulation, and can be considered as a temperature-variable part. Among these, the heat regulation system in the vascular system that plays a major role in heat regulation is localized only to the part without hair, such as the palm (including fingertips), and mainly centers on arteriovenous anastomoses (AVA). The body temperature of the entire human body is adjusted by expanding the blood vessel collection (for example, when you want to lower the body temperature by removing heat, the palm skin temperature rises compared to other skin temperatures, When you want to increase body temperature by preventing disappearance, the skin temperature of the palm falls compared to other skin temperatures).

  In other words, as the degree of fluctuation of the skin temperature accompanying the fluctuation of the blood flow, the palm (including the fingertip (the part where the blood vessel is arteriovenous anastomosed)) and the wrist (the blood vessel is arteriovenous anastomosed) with a small degree of fluctuation By comparing with a portion other than the region where the blood flow has occurred, it is possible to indirectly grasp the fluctuation of the blood flow.

  For example, as shown by 3a in FIG. 3, in a steady state, temperature data 301 detected by the reference body temperature detector 133 attached to the wrist portion of the subject and an adjusted body temperature detector 134 attached to the fingertip portion. It is assumed that the temperature difference from the temperature data 302 detected in is the temperature difference indicated by the arrow 303. As the temperature data 301 and the temperature data 302, for example, an average value for six pieces of data sampled every 500 msec is used.

  From this state, for example, when the blood vessel in the upper arm portion of the subject is pressed and the blood flow is forcibly stopped for a certain period of time (when the blood is blocked), temperature adjustment by the blood flow is performed as shown in 3b of FIG. Therefore, the temperature difference between the temperature data 311 detected by the reference body temperature detection unit 133 and the temperature data 312 detected by the adjusted body temperature detection unit 134 is smaller than the arrow 303 as indicated by the arrow 313. .

  Further, as shown in 3b of FIG. 3, when the pressure of the blood vessel in the upper arm portion of the subject is released in a state where the temperature difference between the temperature data 311 and the temperature data 312 is reduced, the blood vessel in the upper arm portion which is blocked is released. Expands and blood flow resumes. At this time, since the blood vessel diameter becomes larger than that before ischemia, the temperature of the fingertip portion once increased due to ischemia is lower than the original temperature data 302 due to temperature adjustment by blood flow.

  Here, when the vascular endothelial function is damaged, the degree of the decrease is small. Even if the degree of decrease is the same, if the vascular endothelial function is damaged, the time to the lowest temperature becomes longer.

  Because of this, vascular endothelial function is evaluated by monitoring the temperature difference between the temperature of the wrist and fingertip of the subject after pressing the blood vessel in the upper arm of the subject for a certain period of time. can do.

<4. Method of blood pressure measurement and vascular endothelial function measurement>
Next, a method for blood pressure measurement and vascular endothelial function evaluation in the blood pressure measurement device 100 according to the present embodiment will be described. FIG. 4 is a diagram illustrating a state in which blood pressure measurement and vascular endothelial function evaluation are performed using the blood pressure measurement device 100.

  As shown in FIG. 4, with respect to a subject 400 in which the upper arm is inserted into the cuff unit 111 of the blood pressure measurement device 100, the measurer uses the reference of the peripheral blood vessel measurement unit 130 connected to the back surface of the blood pressure measurement device 100. The body temperature detector 133 is attached to the wrist portion of the subject 400, and the adjusted body temperature detector 134 is attached to the fingertip portion of the subject 400.

  In this state, the measurer operates the operation units 112 and 122 to activate the blood pressure measurement unit 221 and the vascular endothelial function evaluation unit 222. Thereby, blood pressure measurement and vascular endothelial function evaluation can be performed simultaneously.

<5. Explanation of each data in blood pressure measurement and vascular endothelial function evaluation>
Next, when blood pressure measurement and vascular endothelial function evaluation are performed, temperature data detected by the peripheral blood vessel measurement unit 130, temperature difference data calculated by the main body unit 110 based on the temperature data, and the main body unit 110 The pressure data detected in will be described with reference to FIG.

  In 5a of FIG. 5, reference numeral 501 denotes temperature data detected by the reference body temperature detector 133 attached to the wrist portion of the subject, and temperature data detected by the adjusted body temperature detector 134 attached to the fingertip portion. The time change of the temperature difference is shown.

  As shown by 5a in FIG. 5, the temperature difference 501 is substantially constant during the resting time, but when the blood pressure is stopped by starting the compression of the blood vessel in the upper arm portion of the subject, Since temperature adjustment is not performed, the temperature difference is reduced. For this reason, the temperature difference gradually decreases during the ischemic time.

  Here, 5b of FIG. 5 shows the time change of the pressure data detected by the pressure sensor 207 in the ischemic time. By driving the pressure pump 203, the cuff part 111 is pressurized at a constant speed. Based on the pulse wave data superimposed on the pressure data detected during pressurization, the minimum blood pressure value and the maximum blood pressure value are calculated.

  When the cuff part 111 is pressurized to a predetermined pressure, the pressurized state is maintained for a predetermined time (for example, 2 minutes). When a predetermined time (for example, 2 minutes) elapses, the ischemic time is finished and the reactive hyperemia time is shifted to. Then, by rapidly exhausting through the exhaust valve 204, the pressure on the blood vessel of the upper arm portion of the subject is released and the blood vessel is expanded, so that blood flow is resumed.

  Returning to 5a of FIG. When the blood flow is resumed after the transition to the reactive hyperemia time, the temperature of the fingertip portion is adjusted, so that the temperature of the subject's fingertip portion returns to the state before ischemia. That is, due to thermal diffusion due to blood flow, the temperature of the fingertip portion decreases, and the temperature difference gradually increases. Thereafter, the blood vessel diameter further increases slightly, and after expanding to the maximum blood vessel diameter, the blood vessel diameter gradually returns to the resting time. For this reason, the blood flow rate once becomes larger than the blood flow rate at the resting time, and gradually approaches the blood flow rate at the resting time after reaching the maximum value, so that the temperature difference gradually increases after reaching the maximum value. In addition, the temperature difference approaches 511 in the resting time.

  Here, when the vascular endothelial function is impaired, the value of the maximum temperature difference (difference between the temperature difference in the resting time and the maximum temperature difference in the reactive hyperemia time) 521 becomes small. Even if the value of the maximum temperature difference 521 is the same, when the vascular endothelial function is damaged, the value of the time 522 until the maximum temperature difference 521 is reached increases. Further, when the blood vessel is hard, the value of the minimum temperature difference (the difference between the temperature difference in the resting time and the minimum temperature difference in the reactive hyperemia time) 523 becomes small.

  For this reason, the maximum temperature difference 521, the minimum temperature difference 523, and the time 522 are calculated as evaluation values indicating the vascular endothelial function based on the temperature difference that is the evaluation parameter, and displayed on the measurer. One can evaluate the subject's vascular endothelial function. In addition, the hardness of the blood vessel of the subject can also be evaluated.

  As described above, in measuring how much the blood vessel clamped by the cuff part 111 is expanded, the change in the temperature difference can be easily eliminated at a low cost by eliminating the influence of the measurer's procedure. It is extremely effective from the viewpoint of.

<6. Flow of blood pressure measurement process and vascular endothelial function evaluation process>
Next, the flow of blood pressure measurement processing and vascular endothelial function evaluation processing in the blood pressure measurement device 100 will be described. 6A and 6B are flowcharts showing the flow of blood pressure measurement processing and vascular endothelial function evaluation processing in the blood pressure measurement device 100.

  For the subject who has inserted the upper arm into the cuff portion 111 of the blood pressure measurement device 100 to which the peripheral blood vessel measurement unit 130 is connected, the measurer uses the reference body temperature detection unit 133 of the peripheral blood vessel measurement unit 130 as the subject's body. When the preparation for measurement is completed by attaching the adjusted body temperature detection unit 134 to the fingertip portion of the subject at the wrist, the blood pressure measurement unit 221 and the vascular endothelial function evaluation unit 222 are activated.

  When the blood pressure measurement unit 221 and the vascular endothelial function evaluation unit 222 are activated by the measurer, the main body 110 of the blood pressure measurement device 100 performs an initialization operation in step S601. Specifically, after the exhaust valve 204 is fully opened and the air in the cuff part 111 is discharged, the zero point of the output of the pressure sensor 207 is adjusted. Thereafter, the exhaust valve 204 is fully closed.

  In step S <b> 602, a temperature measurement start instruction is transmitted from the main body 110 to the peripheral blood vessel measurement unit 130. In step S621, the peripheral blood vessel measurement unit 130 that has received the temperature measurement start instruction starts temperature detection and starts processing for transmitting the detected temperature data to the main body unit 110. Specifically, the temperature data (wrist part) detected by the reference body temperature detector 133 and the temperature data (fingertip part) detected by the adjusted body temperature detector 134 are transmitted to the main body 110.

  In step S603, the calculation of the temperature difference is started based on each temperature data transmitted from the peripheral blood vessel measurement unit 130. Further, in step S604, a message indicating that the subject should be rested is displayed to the subject via the display unit 121. In step S605, counting of a predetermined time (rest time, for example, 3 minutes) is started. To do.

  If it is determined in step S605 that the predetermined time has elapsed, the process proceeds to step S606, and the average value of the temperature differences calculated within the rest time is calculated.

  In step S607, the pressurization pump 203 is driven to start pressurization of the cuff unit 111. In step S608, detection of pressure by the pressure sensor 207 is started.

  In step S609, it is determined whether or not the cuff unit 111 has been pressurized to a predetermined pressure value. If it is determined that the cuff unit 111 has not been pressurized to the predetermined pressure value, the drive of the pressurizing pump 203 is continued.

  On the other hand, if it is determined in step S609 that the pressure has been increased to the predetermined pressure value, the process proceeds to step S610, and the drive of the pressure pump 203 is stopped. Furthermore, in step S611, based on the pulse wave data superimposed on the pressure data detected after the pressurization of the cuff unit 111 is started, the minimum blood pressure value and the maximum blood pressure value are calculated, and the calculated minimum blood pressure value and The maximum blood pressure value is displayed on the display unit 121.

  Further, in step S612, counting for a predetermined time (blood occlusion time, for example, 2 minutes) is started. If it is determined in step S612 that the predetermined time has elapsed, the process proceeds to step S613, and the exhaust valve 204 is fully opened to forcibly exhaust the cuff part 111.

  In step S614, counting of a predetermined time (reactive hyperemia time, for example, 5 minutes) is started. If it is determined in step S614 that the predetermined time has elapsed, the process proceeds to step S615.

  In step S615, the maximum temperature difference 521, the minimum temperature difference 523, and the time 522 are calculated based on the average value of the temperature difference in the rest time calculated in step S606 and the temperature difference calculated after the forced exhaust in step S613. And displayed on the display unit 121 as an evaluation value.

  In step S616, the main body 110 transmits an end instruction to the peripheral blood vessel measurement unit 130. In step S622, the peripheral blood vessel measurement unit 130 ends temperature detection and transmission of the detected temperature data.

  As is clear from the above description, in the blood pressure measurement device 100 according to the present embodiment, when measuring how much the blood vessel of the upper arm portion compressed by the cuff unit 111 has expanded after resumption of blood flow, the degree of expansion of the blood vessel Focusing on the correlation between blood flow and peripheral blood circulation, a configuration is provided in which a reference body temperature detection unit 133 that is attached to the wrist portion and detects temperature, and an adjustment body temperature detection portion 134 that is attached to the fingertip portion and detects temperature did.

  The temperature difference (evaluation parameter) between the temperature detected by the reference body temperature detection unit 133 and the temperature detected by the adjusted body temperature detection unit 134 is calculated.

  Furthermore, the vascular endothelial function is quantitatively evaluated by calculating the maximum temperature difference, the minimum temperature difference, and the time until the maximum temperature difference after the blood flow is resumed as an evaluation value indicating the vascular endothelial function. The configuration.

  Further, the minimum blood pressure value and the maximum blood pressure value are calculated based on pressure data detected when the cuff portion 111 compresses the blood vessel of the upper arm portion.

  As a result, it has become possible to provide a blood pressure measurement device capable of realizing highly accurate vascular endothelial function evaluation by a simple method.

[Second Embodiment]
In the first embodiment, in measuring how much the blood vessel clamped by the cuff portion has expanded after resumption of blood flow, the reference body temperature detector 133 is focused on the correlation between the degree of blood vessel expansion and the peripheral blood circulation. However, the present invention is not limited to this.

  For example, paying attention to the correlation between the degree of vascular dilation and the transmission speed of the pulse wave, the vascular endothelial function is evaluated by measuring the transmission speed of the pulse wave after resuming the blood flow of the blood vessel clamped by the cuff part. You may do it. Details of this embodiment will be described below. Note that the following description will focus on the differences from the first embodiment.

<1. Functional Configuration of Blood Pressure Measuring Device 700>
First, the functional configuration of the blood pressure measurement device 700 according to the present embodiment will be described. FIG. 7 is a diagram illustrating a functional configuration of the blood pressure measurement device 700.

  In FIG. 7, the functional configurations of the main body 110 and the remote control unit 120 are the same as those in the first embodiment, and thus description thereof is omitted here.

  As shown in FIG. 7, the peripheral blood vessel measurement unit 730 includes an upstream pulse wave detection unit 733 attached to the wrist portion of the subject, a downstream pulse wave detection unit 734 attached to the fingertip portion, and upstream pulse wave detection. A measurement control unit 732 that transmits the pulse wave data detected in each of the unit 733 and the downstream pulse wave detection unit 734 to the main body unit 110.

  The upstream pulse wave detection unit 733 and the downstream pulse wave detection unit 734 respectively include infrared light emission units 761 and 771 that emit infrared rays, and infrared light reception units 762 and 772 that receive infrared rays. In the upstream pulse wave detection unit 733 attached to the subject's wrist, the infrared light receiving unit 762 receives the infrared light emitted from the infrared light emitting unit 761 and reflected by the blood vessels inside the wrist part.

  On the other hand, in the downstream pulse wave detector 734 attached to the subject's fingertip portion, the infrared light receiving portion 772 receives the infrared light emitted from the infrared light emitting portion 771 and transmitted through the blood vessel inside the subject's fingertip portion. To do.

  Infrared light emission by the infrared light emitting units 761 and 771 and processing of infrared signals received by the infrared light receiving units 762 and 772 are executed in the pulse wave sensor circuits 752 and 754, respectively. Infrared signals input to the pulse wave sensor circuits 752 and 754 are subjected to waveform shaping in the waveform shaping circuits 751 and 753, and then input to the control unit 750, where peripheral blood vessel measurement data (pulse wave data in this embodiment) is input. Is transmitted to the main body 110 via the connector portion 731.

  In the control unit 750, based on the pulse wave detection start instruction and the pulse wave detection end instruction transmitted from the main body unit 110 via the connector unit 731, light emission by the infrared light emission units 761 and 771, and infrared light reception units 762 and 772 are performed. Controls the reception of light.

<2. Explanation of pulse wave data>
Next, pulse wave data (wrist part) and pulse wave data (fingertip part) detected by the peripheral blood vessel measurement unit 130 and transmitted to the main body 110 will be described. FIG. 8 is a diagram illustrating an example of pulse wave data detected by the peripheral blood vessel measurement unit 730.

  As shown in FIG. 8, the upstream pulse wave detection unit 733 located on the upstream side with respect to the blood flow direction and the downstream pulse wave detection unit 734 located on the downstream side have a difference in detection timing of the corresponding pulse waves. Arise. In FIG. 8, 801 is a pulse wave detected by the upstream pulse wave detection unit 733, and 802 is a pulse wave detected by the downstream pulse wave detection unit 734.

  Here, the time difference between the pulse wave 801 and the corresponding pulse wave 802 (hereinafter, the time difference is referred to as “delay time”) is determined by the mounting position of the upstream pulse wave detection unit 733 and the downstream pulse wave detection unit 734. In addition to the distance to the mounting position, it depends on the degree of expansion of the blood vessel of the upper arm portion compressed by the cuff 111.

  That is, when the blood vessel clamped by the cuff part 111 does not expand and the intra-arterial pressure is larger than the arteriole, the pulse wave transmission speed is slowed down. Be fast enough.

  Therefore, when the distance between the mounting position of the upstream pulse wave detection unit 733 and the mounting position of the downstream pulse wave detection unit 734 is constant, the delay time is set when the blood vessel clamped by the cuff unit 111 is not expanded. Becomes longer. On the contrary, when the blood vessel is sufficiently dilated, the delay time is shortened.

  Thus, in measuring how much the blood vessel clamped by the cuff part 111 is expanded, monitoring the change in the delay time can be easily realized at a low cost by eliminating the influence of the measurer's procedure. It is extremely effective from the viewpoint of.

<3. Explanation of each data in blood pressure measurement and vascular endothelial function evaluation>
Next, when blood pressure measurement and vascular endothelial function evaluation are performed, the pulse wave data detected in the peripheral blood vessel measurement unit 730, the delay time calculated in the main body unit 110 based on the pulse wave data, and the main body unit The pressure data detected at 110 will be described with reference to FIG.

  In 9a of FIG. 9, reference numeral 901 is detected in the downstream pulse wave detection unit 734 attached to the fingertip portion with respect to the pulse wave data detected in the upstream pulse wave detection unit 733 attached to the wrist portion of the subject. The delay time of the corresponding pulse wave data is shown.

  As indicated by 9a in FIG. 9, the delay time 901 is substantially constant during the rest period. In addition, 911 has shown the average value of the delay time in rest time.

  On the other hand, when compression of the blood vessel in the upper arm portion of the subject is started and blood flow is stopped (that is, during the ischemic time), the pulse wave data is not detected, so that the calculation of the delay time is also temporarily stopped. For this reason, there is no data on the delay time during the ischemic time.

  Here, 9b in FIG. 9 shows the time change of the pressure data detected by the pressure sensor 207 during the ischemic time. By driving the pressure pump 203, the cuff part 111 is pressurized at a constant speed. Based on the pulse wave data superimposed on the pressure data detected during pressurization, the minimum blood pressure value and the maximum blood pressure value are calculated.

  9c of FIG. 9 has shown the pulse wave data detected in the upstream pulse wave detection part 733 and the downstream pulse wave detection part 734 in the ischemic time. By driving the pressurizing pump 203, the blood vessel in the upper arm portion of the subject is compressed, so that the amplitude of the pulse wave data decreases as the pressure increases, and the pulse wave data cannot be detected.

  The blood pressure measurement device 700 according to the present embodiment is configured to stop the pressurization pump 203 when the upstream pulse wave detection unit 733 and the downstream pulse wave detection unit 734 can no longer detect pulse wave data. It shall be. Thus, the amplitude of the pulse wave data detected by the upstream pulse wave detection unit 733 and the downstream pulse wave detection unit 734 is monitored, and when the amplitude of the pulse wave data becomes zero (or less than a predetermined value), By adopting a configuration in which the pressurizing pump 203 is stopped, it is possible to reduce the load applied to the upper arm portion of the subject as compared with the case where the pressurization pump 203 is pressurized to a certain pressure regardless of the subject.

  When the pressurization pump 203 is stopped when the pulse wave data cannot be detected, the pressurization state is maintained for a predetermined time (for example, 2 minutes). And after a pressurization state is maintained for a predetermined time (for example, 2 minutes), the ischemic time is ended, and it shifts to the reactive hyperemia time. Then, by performing quick exhaust through the exhaust valve 204, the pressure on the blood vessel in the upper arm portion of the subject is released and the blood vessel is expanded, so that blood flow is resumed.

  Returning to 9a of FIG. When the blood flow is resumed after the transition to the reactive hyperemia time, the blood vessel dilates and the delay time becomes longer than the delay time in the rest time. Thereafter, the blood vessel diameter further increases slightly, and after expanding to the maximum blood vessel diameter, the blood vessel diameter gradually returns to the resting time. For this reason, the delay time also slightly increases after shifting to the reactive hyperemia time, and gradually approaches the rest time after reaching the maximum value.

  Here, when the vascular endothelial function is damaged, the value of the difference value (difference between the delay time in the resting time and the maximum delay time in the reactive hyperemia time) 922 becomes small. Even if the difference value 922 is the same, the value of the time 923 increases when the vascular endothelial function is damaged. Furthermore, when the blood vessel is hard, the value of the difference value 921 becomes small.

  Thus, based on the delay time that is the evaluation parameter, the difference values 921 and 922 and the time 923 are calculated as evaluation values indicating the vascular endothelial function and displayed to the measurer. A person's vascular endothelial function can be evaluated. In addition, the hardness of the blood vessel of the subject can also be evaluated.

<4. Flow of blood pressure measurement process and vascular endothelial function evaluation process>
Next, the flow of blood pressure measurement processing and vascular endothelial function evaluation processing in the blood pressure measurement device 700 will be described. 10A and 10B are flowcharts showing the flow of blood pressure measurement processing and vascular endothelial function evaluation processing in the blood pressure measurement device 700.

  For the subject who has inserted the upper arm into the cuff part 111 of the blood pressure measurement device 100 to which the peripheral blood vessel measurement unit 730 is connected, the measurer uses the upstream pulse wave detection unit 733 of the peripheral blood vessel measurement unit 730 as the subject. When the preparation for measurement is completed by attaching the downstream pulse wave detection unit 734 to the fingertip portion of the subject at the wrist portion of the subject, the blood pressure measurement unit 221 and the vascular endothelial function evaluation unit 222 are activated.

  When the blood pressure measurement unit 221 and the vascular endothelial function evaluation unit 222 are activated by the measurer, the main body 110 of the blood pressure measurement device 700 performs an initialization operation in step S1001. Specifically, after the exhaust valve 204 is fully opened and the air in the cuff part 111 is discharged, the zero point of the output of the pressure sensor 207 is adjusted. Thereafter, the exhaust valve 204 is fully closed.

  In step S <b> 1002, a pulse wave detection start instruction is transmitted from the main body 110 to the peripheral blood vessel measurement unit 730. In step S1021, the peripheral blood vessel measurement unit 730 that has received the pulse wave detection start instruction starts pulse wave detection and starts processing for transmitting the detected pulse wave data to the main body unit 110. Specifically, the pulse wave data (wrist part) detected by the upstream pulse wave detector 733 and the pulse wave data (fingertip part) detected by the downstream pulse wave detector 734 are transmitted to the main body 110. .

  In step S1003, the calculation of the delay time is started based on each pulse wave data transmitted from the peripheral blood vessel measurement unit 730. In step S1004, a message indicating that the subject should be rested is displayed to the subject via the display unit 121. In step S1005, counting of a predetermined time (rest time, for example, 3 minutes) is started. To do.

  If it is determined in step S1005 that the predetermined time has elapsed, the process proceeds to step S1006, and the average value of the delay times calculated within the rest time is calculated.

  In step S1007, the calculation of the delay time is once stopped. In step S1008, the pressurization pump 203 is driven to start pressurization of the cuff unit 111. In step S1009, pressure detection by the pressure sensor 207 is started.

  In step S1010, it is determined whether or not the pulse wave data is detected in the peripheral blood vessel measurement unit 730. If it is determined that the pulse wave data is detected, the drive of the pressurizing pump 203 is continued.

  On the other hand, if it is determined in step S1010 that the pulse wave data is no longer detected, the process proceeds to step S1011 and the driving of the pressurizing pump 203 is stopped. Further, in step S1012, the minimum blood pressure value and the maximum blood pressure value are calculated based on the pulse wave data superimposed on the pressure data detected after the pressurization of the cuff unit 111 is started, and the calculated minimum blood pressure value and The maximum blood pressure value is displayed on the display unit 121.

  Furthermore, in step S1013, counting of a predetermined time (ischemic time, for example, 2 minutes) is started. If it is determined in step S1013 that the predetermined time has elapsed, the process proceeds to step S1014, and the exhaust valve 204 is fully opened to forcibly exhaust the cuff part 111.

  In step S1015, calculation of the delay time is restarted, and in step S1016, counting of a predetermined time (reactive hyperemia time, for example, 5 minutes) is started. If it is determined in step S1016 that the predetermined time has elapsed, the process proceeds to step S1017.

  In step S1017, based on the average value of the delay time in the rest time calculated in step S1006 and the delay time calculated after forced exhaust in step S1014, difference values 921, 922 and time 923 are calculated, and the evaluation value Is displayed on the display unit 121.

  In step S1018, the main body 110 transmits an end instruction to the peripheral blood vessel measurement unit 730. In step S1022, the peripheral blood vessel measurement unit 730 ends the pulse wave detection and transmission of the detected pulse wave data.

  As is clear from the above description, in the blood pressure measurement device 700 according to the present embodiment, the degree of dilation of the blood vessel is measured in measuring how much the blood vessel of the upper arm compressed by the cuff unit 111 has dilated after resumption of blood flow. Focusing on the correlation between the pulse wave transmission time and the pulse wave transmission time, the upstream pulse wave detection unit that is attached to the wrist part and detects the pulse wave, and the downstream pulse wave detection part that is attached to the fingertip part and detects the pulse wave, It was set as the structure to distribute.

  The time difference between the pulse wave detected by the upstream pulse wave detection unit and the corresponding pulse wave detected by the downstream pulse wave detection unit is calculated as a delay time (evaluation parameter).

  Furthermore, by calculating the difference value between the delay time after resumption of blood flow and the delay time in the resting time, and the time until the difference value is maximized as an evaluation value indicating the vascular endothelial function, the vascular endothelial function Was configured to be evaluated quantitatively.

  Further, the minimum blood pressure value and the maximum blood pressure value are calculated based on pressure data detected when the cuff portion 111 compresses the blood vessel of the upper arm portion.

  Further, the pressurization pump that is driven by the cuff unit 111 to compress the blood vessel in the upper arm portion is configured to stop depending on the presence or absence of a pulse wave detected by the peripheral blood vessel measurement unit 730.

  As a result, it has become possible to provide a blood pressure measurement device capable of realizing highly accurate vascular endothelial function evaluation by a simple method.

[Third Embodiment]
In the first embodiment, a thermistor is arranged as the peripheral blood vessel measurement unit 130, and in the second embodiment, a pulse wave sensor is arranged as the peripheral blood vessel measurement unit 730. However, the present invention is limited to this. Instead, both the thermistor and the pulse wave sensor may be arranged in the peripheral blood vessel measurement unit.

  In the first and second embodiments, the blood pressure measurement process and the vascular endothelial function evaluation process are performed at the same time. However, the present invention is not limited to this, and any one of the processes can be executed individually. It may be configured.

  In the first embodiment, the pressure is applied until the cuff part 111 reaches a predetermined pressure value. In the second embodiment, the pressure is applied until no pulse wave data is detected. It is not limited. When a pulse wave sensor is attached as a peripheral blood vessel measurement unit, it is possible to select whether to pressurize the cuff unit 111 until a predetermined pressure value is reached or until no pulse wave sensor is detected. It may be configured.

  FIG. 11 illustrates the relationship between the modes when the measurement modes can be selected. In FIG. 11, “blood pressure measurement mode” is a mode in which only the blood pressure measurement process is executed. In this mode, the cuff unit 111 is automatically pressurized to a predetermined pressure value. When the blood pressure measurement mode is selected, the minimum blood pressure value and the maximum blood pressure value may be calculated based on the pressure data measured during pressurization, or the constant speed exhaust valve 208 may be The maximum blood pressure value and the minimum blood pressure value may be calculated based on pressure data measured at the time of pressure reduction.

  The “vascular endothelial function evaluation mode” is a mode in which only the vascular endothelial function evaluation process is executed. In the case where a pulse wave sensor is attached as a peripheral blood vessel measurement unit, It is configured so that “variable blood pressure control mode” can be selected. The ischemic pressure fixing mode is a mode in which pressurization is performed to a predetermined pressure value, and the ischemic pressure variable mode is a mode in which pressurization is performed until no pulse wave data is detected.

  The “blood pressure measurement + vascular endothelial function evaluation mode” is a mode in which both the blood pressure measurement process and the vascular endothelial function evaluation process are executed. In this mode as well, when a pulse wave sensor is attached as a peripheral blood vessel measurement unit, the “ischemic blood pressure fixing mode” and the “ischemic blood pressure variable mode” can be selected. And

  When the variable ischemic blood pressure mode is selected, it is determined whether or not the pulse wave data is correctly transmitted from the peripheral blood vessel measurement unit before the pressurization pump is driven. In this case, an error message may be displayed and the blood pressure measurement process may be stopped or automatically switched to the anti-spasmodic pressure mode.

[Fourth Embodiment]
In the second embodiment, the upstream pulse wave detection unit is attached to the wrist part and the downstream pulse wave detection part is attached to the fingertip part. However, the present invention is not limited to this and is attached along the blood flow direction. If it does, you may comprise so that it may mount | wear to another part.

  The present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Therefore, in order to make the scope of the present invention public, the following claims are attached.

Claims (6)

A first temperature detection unit that is attached to the body surface of the site where the blood vessel is anastomosed with an artery and vein, and detects first temperature data;
It is a part other than the part where the blood vessel is anastomosed and is attached to the body surface upstream of the position where the first temperature detection unit is attached, and the second temperature data is obtained. A second temperature detector for detecting;
A pressurizing pump that pressurizes a cuff that compresses a portion upstream of the position where the second temperature detection unit is attached in the blood flow direction;
A first pulse wave detection unit mounted with the first temperature detection unit and detecting first pulse wave data;
A second pulse wave detection unit that is mounted together with the second temperature detection unit and detects second pulse wave data;
During pressurization by said pressurizing pump, based on the output of the pressure sensor for detecting the pressure of a portion which is pressed by the cuff, a first calculation means for calculating a minimum blood pressure value and systolic blood pressure value,
A second calculating means for calculating an evaluation value related to the vascular endothelial function,
The second calculation means includes:
After the ischemic over a predetermined time by pressing by the cuff, in a case where to resume blood flow, the difference value between the first temperature data detected after reperfusion and the second temperature data Means for calculating a first evaluation value related to the vascular endothelial function based on :
Based on a delay time that is a time difference between each pulse wave included in the first pulse wave data detected after the resumption of blood flow and each corresponding pulse wave included in the second pulse wave data. Means for calculating a second evaluation value relating to vascular endothelial function;
Blood pressure measuring device which comprises a. The first evaluation value is a maximum value of a difference value between the first temperature data and the second temperature data detected after resumption of blood flow, and the first value detected before being compressed by the cuff part. The blood pressure measurement device according to claim 1, comprising a difference between a difference value between the temperature data of 1 and the second temperature data. The first evaluation value includes a time until a difference value between the first temperature data and the second temperature data detected after resumption of blood flow becomes maximum. The blood pressure measurement device described. The second evaluation value includes a difference between a maximum value of the delay time after resumption of blood flow and the delay time before being compressed by the cuff part . 1. The blood pressure measurement device according to item 1 . The blood pressure measurement device according to any one of claims 1 to 3, wherein the second evaluation value includes a time until the delay time becomes maximum after resumption of blood flow. Pressure by the pressurizing pump, according to claim 1 to 5, characterized in that said first pulse wave data and / or said second pulse wave data is controlled to stop when it becomes impossible to detect The blood pressure measurement device according to any one of the above.

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