JP2008296061A - Circulatory dynamics measuring instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circulatory dynamics measuring instrument which enters wave motions from a biological surface noninvasively, analyzes the condition of blood and so on from movement and location by reflecting it on a body fluid flowing through a living body, and measures circulatory dynamics correctly without being affected by blood pressure when assessing health condition seeking the circulatory dynamics. <P>SOLUTION: A circulatory dynamics measuring instrument has a means which sends and receives wave motion from a skin surface and detects circulatory dynamics in a living body noninvasively and a means which detects the blood pressure of a measurement site as basic construction. The measurement is carried out precisely by using a correction coefficient calculated from a vascular diameter and average blood-pressure value calculated from a maximum blood-pressure value and a minimum blood-pressure value for correction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a body fluid that circulates in a living body and a tissue measuring device that constitutes a circulatory organ, and more particularly to a technique for grasping the state of blood and evaluating health, diagnosing diseases, evaluating drug effects, and the like.

Conventionally, various methods using blood information have been performed in order to evaluate the health of a living body, diagnose a disease, grasp the influence of a drug on a living body, and the like. For example, medically, there is a method in which blood is collected from a living body, and the blood is applied to a component analyzer to obtain a circulatory dynamic from the ratio of various blood components contained in the blood to evaluate the health state. As a conventional example, a method announced by Keiji Kikuchi in the title of “Measurement of whole blood fluidity using a capillary model”, that is, a microchannel that is collected from a subject and manufactured using a lithographic technique A method for measuring blood rheology from the passage time of blood flow under constant pressure using an array is known. (For example, see Non-Patent Document 1)
Keiji Kikuchi, “Rapid and Quantitative Evaluation of Food Functionality Using Blood Rheology Measurement Device MC-FAN”, Food Research Result Information, National Food Research Institute, 1998, No. 11

  The problem to be solved by the present invention is to evaluate health condition and circulatory dynamics in consideration of individual differences without blood collection.

  In the conventional blood rheology measurement method using a microchannel array, in order to collect blood from a subject, blood must be collected by inserting a needle into the elbow using an injection needle. Therefore, even if an in vivo test is performed to see the effect of food ingredients on blood rheology, blood cannot be collected from the same person several times a day, and there is a problem that continuous tests are difficult. In addition, even if an individual leaves the medical institution to collect blood at home or the like and perform blood rheology measurement, one method using a microchannel array as in the conventional example cannot place the device at home. There is also a problem that measurement cannot be performed only at a medical institution because appropriate processing cannot be performed.

  Means for solving the above problem is to detect and detect the flow velocity of blood flowing through a blood vessel in the form of a Doppler shift signal by transmitting ultrasonic waves reflected from the skin surface of a living body and receiving the reflected ultrasonic waves. This is a means for obtaining a temporal change component of the blood flow velocity from the Doppler shift signal and measuring a blood rheology which is one of the circulatory dynamics from the change component to evaluate the health condition. Specifically, blood rheology is obtained from the maximum velocity component of the blood flow velocity component during a single pulse, and as a result, if the result is that the blood rheology is small, an evaluation method is performed to give an evaluation that the blood is healthy. .

  Here, when determining blood rheology, it is important to accurately determine the flow velocity of blood flowing through a blood vessel. However, blood flow is greatly affected by blood pressure. Therefore, in order to accurately determine the blood flow, it is necessary to correct the influence of blood pressure. This can be easily inferred from the following Poire's equation.

Q = πr ⁴・ △ P / (8ηl) (Formula 1)
Here, Q is the flow rate, r is the inner diameter of the tube, η is the viscosity of the fluid, l is the length of the tube, and ΔP is the pressure difference. Q is the maximum speed Vm and the inner diameter r of the rod,
Q = πr ² Vm / 2 (Formula 2)
It can be expressed as. If these two formulas are arranged, formula 3 is obtained.

Vm / △ P = A ・ 1 / η (A = r ² / 4l) (Formula 3)
As shown in Equation 3, it can be seen that there is a relationship between the flow rate, the pressure difference, and the viscosity. When this is replaced with biological information, it can be said that there is a correlation between the flow velocity flowing through the blood vessel, blood pressure, and blood rheology. For example, even blood having similar blood rheology has different blood flow rates when blood pressure is different, and it is difficult to obtain accurate blood rheology only from the flow velocity flowing through the blood vessels. That is, when obtaining in-vivo information, it can be said that it is difficult to obtain accurate circulation dynamics from the flow velocity of blood flowing through a blood vessel without considering blood pressure.

  In addition, when correcting the influence of blood pressure, it is not known what blood pressure value (for example, maximum blood pressure value or minimum blood pressure value) should be used for correction. In the present invention, when correction is performed, an average blood pressure value is considered as a representative value of the person's blood pressure. The average blood pressure value is expressed by Equation 4 published in standard physiology and the like.

Pm = Pd + Pp / 3 (Formula 4)
Here, Pm is an average blood pressure value, Pd is a diastolic blood pressure, and Pp is a pulse pressure. However, this equation agrees with the measurement at the upper arm. For example, it cannot be applied to the aorta such as the carotid artery or the arteriole at the fingertip. That is, Equation 4 is an average blood pressure value measured at the upper arm region, but is not an average blood pressure value measured at other regions. This is because, as shown in FIG. 12, the blood pressure waveform varies depending on the region, and the average blood pressure value that is the center of gravity of the waveform also varies.

  Therefore, in order to perform correction using the average blood pressure value obtained by Equation 4 and accurately obtain the blood rheology, there is a limitation that the upper arm portion must always be measured.

  Therefore, the following means are used to select the measurement site, to obtain the average blood pressure value, and to obtain the blood rheology accurately.

  First, a hemodynamic measurement unit is provided in the blood pressure measurement unit. As a result, the blood pressure measurement unit and the circulatory dynamics measurement unit match, so that when blood rheology is evaluated, the influence of blood pressure can be accurately corrected.

  An average blood pressure value is used as a blood pressure value for correcting the influence of blood pressure. Since it cannot be said that the person's blood pressure can be expressed only by the maximum blood pressure value or the minimum blood pressure value, the average blood pressure value is obtained and used by an expression including both.

  It has been empirically known that when the blood pressure measurement unit is the upper arm, it can be obtained by Equation 4. This is also confirmed from the blood pressure waveform at the upper arm region. However, since blood pressure waveforms are different in other parts, an expression for obtaining an average blood pressure value corresponding thereto is prepared.

  The average blood pressure value used for correction is obtained from Equation 5 using the maximum blood pressure value and minimum blood pressure value obtained by the blood pressure measurement unit and the correction coefficient C determined from the blood vessel diameter obtained by the circulation dynamics measurement unit.

Pm = Pd + (Ps-Pd) / C (Formula 5)
Here, Pd is the minimum blood pressure value, Ps is the maximum blood pressure value, and C is a correction coefficient obtained from the blood vessel diameter. For example, in the case of the upper arm part, C = 3 may be used. Further, C = 2 may be used for the aorta, and C = 4 may be used for the peripheral artery. When these values are used, the average blood pressure value obtained from the center of gravity of the blood pressure waveform is the same.

  Moreover, it is described in standard physiology etc. that a blood vessel diameter and a blood pressure are related, and a blood pressure waveform can be estimated by measuring a blood vessel diameter. The average blood pressure value of the estimated blood pressure waveform is obtained by Equation 5. Since the correction coefficient C depends on the blood pressure waveform, the correction coefficient C can be determined by measuring the blood vessel diameter. Therefore, by using Equation 5, it is possible to obtain an average blood pressure value without selecting a region, and to obtain blood rheology with high accuracy.

  As a result, the blood pressure measurement unit and the circulatory dynamics measurement unit are not limited, and the health condition can be accurately evaluated regardless of the measurement site.

  According to the present invention, a measuring device that detects information on the circulatory dynamics inside the living body by transmitting and receiving waves from the surface of the living body to the inside is provided with a function for detecting the circulatory dynamics and a function for detecting the blood pressure of the living body. By using the mean blood pressure value calculated using the correction coefficient obtained from the diameter, it is possible to obtain a highly accurate measurement of circulatory dynamics. In addition, since measurement can be performed without blood collection, continuous testing is facilitated, measurement is not limited, and measurement can be performed at home.

  The basic configuration of the circulatory dynamics measuring apparatus according to the present invention includes a means (circulation sensor) for non-invasively detecting circulatory dynamics in a living body by transmitting and receiving waves from the skin surface, and a means for detecting blood pressure at a measurement site (blood pressure measurement) Part).

  The circulation sensor detects biological information such as blood flow velocity, blood flow volume, blood vessel diameter, and blood vessel thickness by transmitting and receiving waves from the skin surface. The change in blood flow velocity is detected by measuring the amount of Doppler shift caused by the Doppler effect, and the blood vessel diameter is detected by measuring the time delay reflected back to the blood vessel. In general, an ultrasonic wave is used for a wave used for blood flow velocity detection, but other waves such as a laser may be used.

  In addition, by arranging a circulation sensor in the blood pressure measurement unit, the influence of blood pressure is accurately corrected. Further, the average blood pressure value used for correcting the blood pressure is obtained using Equation 5.

  Next, the measurement principle of the circulatory dynamics measuring apparatus of the present invention will be described. The method for measuring circulatory dynamics is to determine the circulatory dynamics from the form of the temporal change of the circulatory component that appears during the pulsation of the pulse. Specifically, blood rheology is sought as circulatory dynamics. FIG. 1 shows a graph of the time change associated with the pulsation of the blood flow velocity. A characteristic component of blood rheology is the maximum blood flow velocity Vx corrected by the average blood pressure value, and the blood rheology and the maximum blood flow velocity Vx are correlated.

Hereinafter, a circulatory dynamics measuring apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.
(Example)
FIG. 2 is a view showing the appearance of the living body 2 and the pressure measuring unit 4. Examples of the part of the living body 2 include relatively easily exposed places such as a neck, an upper arm, a wrist, and a fingertip.

  FIG. 3 shows an example of the living body 2, the circulation sensor 1 of the circulatory dynamics measuring device, the pressure measuring unit 4, and the blood vessel 21 in the living body. Circulation sensor 1 is installed so that the transmission / reception unit faces the living body, and is arranged so as to be in contact with the surface of the living body. In this embodiment, transmission and reception are performed using ultrasonic waves. The circulation sensor 1 is arranged in the pressure measurement unit 4 so that the blood pressure value of the blood flow measurement unit can be measured. If the microphone 42 and the circulation sensor 1 are at a position where the blood vessel 21 to be measured can be observed, there is no particular relationship with the direction of blood flow. That is, the microphone 42 or the circulation sensor 1 may be provided in the direction of blood flow (closer to the heart). There is no causal relationship between the order of the microphone 42 and the circulation sensor 1 and the measurement result.

  The circulation sensor 1 shown in FIG. 3 is an example in which the transmission piezoelectric element 11 and the reception piezoelectric element 12 are fixed in the resin 13, but the circulation sensor 1 shown in FIG. In the circulation sensor 1 shown in FIG. 4, a transmitting piezoelectric element 11 and a receiving piezoelectric element 12 are fixed with a conductive adhesive 15 on a substrate 14 that attenuates the propagation of ultrasonic waves. An example of the substrate to be used is a glass epoxy substrate. The piezoelectric element can be arranged with higher accuracy than the method of fixing the piezoelectric element in the resin, the noise can be suppressed by using a substrate that attenuates the ultrasonic wave, and the circulation sensor 1 having a high SN ratio can be manufactured. The transmitting piezoelectric element 11 and the receiving piezoelectric element 12 are connected to a pattern (not shown) on the substrate 14 by a wire bond 16 so that the transmitting piezoelectric element 11 and the receiving piezoelectric element 12 can be driven. The transmitting piezoelectric element 11 and the receiving piezoelectric element 12 are coated with a resin 17. The resin 13 protects the transmitting piezoelectric element 11 and the receiving piezoelectric element 12 and further transmits and receives ultrasonic waves efficiently in the living body by achieving acoustic matching with the living body. The resin 13 may have a multi-layer structure, and if a soft resin that eliminates the wrinkles of the living body or the air layer due to skin phosphorus is used for the layer in contact with the living body, the ultrasonic wave is not attenuated by the air layer, and transmission and reception can be performed efficiently.

  FIG. 5 shows a block diagram showing an internal configuration of the signal processing unit 3 of the circulatory dynamics measuring apparatus according to the embodiment and a connection state of the signal processing unit 3, the circulation sensor 1 and the pressure measuring unit 4. As shown in the figure, the signal processing unit 3 is roughly configured by a drive unit 31, a reception unit 32, a signal calculation unit 33, an output unit 34, and a pressure signal reception unit 35.

  The driving unit 31 according to the embodiment vibrates the transmitting piezoelectric element 11 installed in the circulation sensor 1 and transmits a driving voltage for making an ultrasonic wave incident on the blood vessel 21. The receiving unit 32 receives a voltage generated when the receiving piezoelectric element 12 installed in the circulation sensor 1 receives an ultrasonic wave. The blood pressure value measured by the pressure measuring unit 4 is converted into a voltage, and the pressure signal receiving unit 35 receives the signal. The pressure measurement unit 4 includes a compression band 41, a pressure operation unit (not shown), and a microphone 42. The pressure of the compression band 41 is adjusted by the pressure operation unit. Further, the pressure operation unit measures the pressure value of the compression band 41. When the pressure of the compression band 41 is set to be equal to or higher than the maximum blood pressure value of the living body 2, the blood flow in the blood vessel 21 is stopped, and sound from the blood vessel is eliminated. Further, even if the pressure of the compression band 41 is set to be equal to or lower than the minimum blood pressure value of the living body 2, there is no sound from the blood vessels. This sound is detected by the microphone 42, and the pressure signal receiving unit 35 sends the data of the maximum blood pressure value and the minimum blood pressure value to the signal calculation unit 33.

  The pressure measuring unit 4 may be as shown in FIG. The pressure measurement unit 4 in FIG. 6 includes a compression band 41, a pressure operation unit (not shown), and a vibration sensor 43. The pressure of the compression band 41 is adjusted by the pressure operation unit. In addition, the pressure operation unit measures the pressure value of the compression band 41. When the pressure in the compression band 41 is made higher than the maximum blood pressure value of the living body 2, the blood flow in the blood vessel 21 stops. Thereafter, when the pressure of the compression band 41 is lowered, the vibration increases with the blood flow, and when further lowered, the vibration suddenly decreases. This vibration is detected by the vibration sensor 46, and the pressure signal receiving unit 35 transmits a signal to the signal calculating unit 33 with the pressure at which the vibration is increased as the highest blood pressure value and the pressure at which the vibration is reduced as the lowest blood pressure value. With the structure as shown in FIG. 6, the vibration sensor 43 is connected to the compression band 41 with a pipe as shown in the figure, and if vibration is transmitted, there is no need to be near the compression band 41 and the structure can be simplified. There are advantages.

  Further, the pressure measuring unit 4 may be as shown in FIG. The pressure measurement unit 4 in FIG. 7 includes a compression band 41, a pressure operation unit (not shown), and a pressure sensor 44. In the compression band 41, the pressure is adjusted to be equal to or lower than the maximum blood pressure value of the living body by the pressure operation unit. The compression band 41 can press the living body 2 flatly, and a pressure sensor 44 disposed on the blood vessel 21 detects a pressure corresponding to the pulsation of the blood vessel 21, that is, a pulse pressure. With this method, it is possible to obtain a pressure waveform for each heartbeat while non-invasive. The pressure signal receiver 35 transmits a pressure waveform signal to the signal calculator 33.

  The signal calculation unit 33 executes various processes related to the measurement of circulatory dynamics by executing a processing program stored in a storage area (not shown) provided therein, and outputs the processing results to the output unit 34. . In addition, the signal calculation unit 33 calculates the Doppler effect due to blood flow by comparing the frequency of the ultrasonic wave emitted from the receiving piezoelectric element 12 with the frequency of the received ultrasonic wave. Then, the blood flow velocity flowing through the blood vessel 21 is calculated from the change in frequency, and the time change of the velocity is obtained. Further, in the signal calculation unit 33, the blood flow velocity changes as the blood pressure in the living body changes due to tension or the like, and therefore the time change of the velocity is calculated using the signal obtained from the pressure measurement unit 4. Execute the calculation to be corrected. Therefore, it is possible to correct the influence of tension or the like and the influence of blood pressure due to individual differences, and an accurate blood rheology can be obtained. For example, if the blood flow rate is different because the blood pressure values are different while actually having the same blood rheology, the blood rheology will be different from the blood flow rate only from the blood flow rate, and accurate judgment cannot be made. By measuring the blood pressure value, this can be prevented. Also, when measuring the blood flow measurement unit and the blood pressure measurement unit at different sites, for example, if blood pressure measurement is performed at the upper arm part and blood flow measurement is performed at the fingertip part, the blood pressure values at the upper arm part and the fingertip part are Because it is different, it cannot be accurately reflected in determining blood rheology. However, these problems can be solved by using the present embodiment. The shape of the temporal change in blood flow velocity that appears during the pulsation of the pulse has a correlation with the rheology of blood, and the blood rheology is obtained as the circulation dynamics from the change in blood flow velocity that appears during the pulsation. For example, if the blood flow change is large, it can be said that the blood has a low viscosity.

  When obtaining the average blood pressure value Pm by the signal calculation unit 33, Expression 5 is used.

  C transmits ultrasonic waves in a pulse from the transmitting piezoelectric element 11 of the circulation sensor 1 and measures the time of reception by the receiving piezoelectric element 12, thereby measuring the diameter of the blood vessel and determining C. C does not need to be an integer, and Pm is determined by using an appropriate C such as C = 3.5 according to the blood vessel diameter. By calculating the average blood pressure value as in Expression 5, the average blood pressure value can be determined in Expression 5 regardless of the measurement site. Using this average blood pressure value, blood flow velocity is corrected and blood rheology is obtained.

  Next, the results of the rheology measurement apparatus using the apparatus of the present invention and the results of the evaluation of accuracy are shown. As reference data, the measurement results of a blood rheology measurement device (MC-FAN) using the microchannel array described in the conventional example were used. MC-FAN is a device that allows blood collected to flow through a microchannel array and evaluates blood rheology from the passage time of blood. FIG. 11 shows measurement data of whole blood passage time, maximum blood flow velocity Vx, and blood pressure values (maximum blood pressure value and minimum blood pressure value) in MC-FAN of 10 subjects. The measurement site was the left index finger. The maximum blood flow velocity Vx was obtained from the Doppler shift amount obtained from the circulation sensor 1.

  FIG. 8 shows the result when the blood pressure value is not corrected, and FIG. 10 shows the result obtained by this method. Even when the blood pressure value was not corrected, there was a correlation between the maximum blood flow velocity Vx and the whole blood passage time, but an abnormal value was observed. This is due to the influence of individual differences in blood pressure, and such a problem can be eliminated by using this method.

Further, in the case of correction using the average blood pressure value, FIG. 9 shows the result when using the generally known expression 4, and FIG. 10 shows the result obtained by this method. As a specific method of correction, it was obtained by multiplying the maximum blood flow velocity Vx by the reciprocal of the obtained average blood pressure value. In FIG. 10, 2.5 is used as the correction coefficient obtained from the blood vessel diameter. Comparing the correlation coefficient R ² in this case, when corrected by equation 4 for R ² = .7195, results of the present method was R ² = .7255. From this, it can be said that it is effective to correct the maximum blood flow velocity Vx with the average blood pressure value obtained by this method.

It is a graph of the time change accompanying the pulse beat of the blood flow velocity which the circulatory dynamics measuring device of the present invention measures. It is the figure which showed the external appearance of the biological body and the blood-pressure measurement part about a present Example. It is the figure which showed the relationship between a biological body, a circulation sensor, and a blood-pressure measurement part about an Example. It is a figure which shows one example of a circulation sensor. It is a block diagram which shows the connection state of the internal structure of a signal processing part, and a circulation sensor and a blood-pressure measurement part about an Example. It is a figure which shows one example of a blood-pressure measurement part. It is a figure which shows one example of a blood-pressure measurement part. It is a figure which shows the relationship between the maximum blood flow velocity Vx when not correct | amending, and the whole blood passage time. It is a figure which shows the relationship between the maximum blood flow velocity Vx when corrected with the average blood pressure value calculated | required using Formula 4, and whole blood passage time. It is a figure which shows the relationship between the maximum blood flow velocity Vx when corrected using this method, and whole blood passage time. It is the figure which showed the table | surface of measurement data. It is the figure which showed the relationship between the blood vessel diameter and a pressure waveform.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Circulation sensor 2 Living body 3 Signal processing part 4 Pressure measurement part 11 Transmission piezoelectric element 12 Reception piezoelectric element 13 Resin 14 Substrate 15 Conductive adhesive 16 Wire bond 21 Blood vessel 31 Drive part 32 Reception part 33 Signal calculation part 34 Output part 35 Pressure Signal Receiver 41 Compression Belt 42 Microphone 43 Vibration Sensor 44 Pressure Sensor

Claims (7)

In a circulatory dynamics measuring device that detects the circulatory dynamics of blood circulating inside the living body by transmitting and receiving waves from the surface of the living body to the blood inside the living body,
A circulation sensor for detecting the circulation dynamics;
A drive unit for driving the circulation sensor;
A circulation signal receiver for receiving a signal from the circulation sensor;
A blood flow state detection unit that is disposed on the side of the circulation sensor and used to measure the blood pressure of the living body;
A pressure signal receiving unit that receives a signal from a blood pressure measurement unit that measures blood pressure based on the detection of the blood flow state detection unit;
A signal calculation unit that executes a processing program related to the circulation dynamics using data obtained from the drive unit, the circulation signal reception unit, and the pressure signal reception unit;
An output unit that outputs a processing result by the signal calculation unit;
The signal calculation unit includes a value correlated with a blood flow velocity flowing through the blood vessel in the living body detected by the circulation sensor, a blood pressure value obtained from the blood pressure measurement unit, and a blood vessel diameter of the blood vessel measured by the circulation sensor. A circulatory dynamics measuring device characterized in that blood rheology is obtained using an average blood pressure value calculated using a correction coefficient determined by using the correction coefficient. In a circulatory dynamics measuring device that detects the circulatory dynamics of blood circulating inside the living body by transmitting and receiving waves from the surface of the living body to the blood inside the living body,
A circulation sensor for detecting the circulation dynamics;
A drive unit for driving the circulation sensor;
A circulation signal receiver for receiving a signal from the circulation sensor;
A microphone disposed on the side of the circulation sensor and used to measure blood pressure of the living body;
A pressure signal receiving unit that receives a signal from a blood pressure measurement unit that measures blood pressure based on detection of the microphone;
A signal calculation unit that executes a processing program related to the circulation dynamics using data obtained from the drive unit, the circulation signal reception unit, and the pressure signal reception unit;
An output unit that outputs a processing result by the signal calculation unit;
The signal calculation unit includes a value correlated with a blood flow velocity flowing through the blood vessel in the living body detected by the circulation sensor, a blood pressure value obtained from the blood pressure measurement unit, and a blood vessel diameter of the blood vessel measured by the circulation sensor. A circulatory dynamics measuring device characterized in that blood rheology is obtained using an average blood pressure value calculated using a correction coefficient determined by using the correction coefficient. In a circulatory dynamics measuring device that detects the circulatory dynamics of blood circulating inside the living body by transmitting and receiving waves from the surface of the living body to the blood inside the living body,
A circulation sensor for detecting the circulation dynamics;
A drive unit for driving the circulation sensor;
A circulation signal receiver for receiving a signal from the circulation sensor;
A vibration sensor which is disposed on the side of the circulation sensor and used to measure blood pressure of the living body;
A pressure signal receiving unit that receives a signal from a blood pressure measurement unit that measures blood pressure based on detection of the vibration sensor;
A signal calculation unit that executes a processing program related to the circulation dynamics using data obtained from the drive unit, the circulation signal reception unit, and the pressure signal reception unit;
An output unit that outputs a processing result by the signal calculation unit;
The signal calculation unit includes a value correlated with a blood flow velocity flowing through the blood vessel in the living body detected by the circulation sensor, a blood pressure value obtained from the blood pressure measurement unit, and a blood vessel diameter of the blood vessel measured by the circulation sensor. A circulatory dynamics measuring device characterized in that blood rheology is obtained using an average blood pressure value calculated using a correction coefficient determined by using the correction coefficient. In a circulatory dynamics measuring device that detects the circulatory dynamics of blood circulating inside the living body by transmitting and receiving waves from the surface of the living body to the blood inside the living body,
A circulation sensor for detecting the circulation dynamics;
A drive unit for driving the circulation sensor;
A circulation signal receiver for receiving a signal from the circulation sensor;
A pressure sensor disposed on the side of the circulation sensor and used to measure blood pressure of the living body;
A pressure signal receiving unit that receives a signal from a blood pressure measurement unit that measures blood pressure based on detection of the pressure sensor;
A signal calculation unit that executes a processing program related to the circulation dynamics using data obtained from the drive unit, the circulation signal reception unit, and the pressure signal reception unit;
An output unit that outputs a processing result by the signal calculation unit;
The signal calculation unit includes a value correlated with a blood flow velocity flowing through the blood vessel in the living body detected by the circulation sensor, a blood pressure value obtained from the blood pressure measurement unit, and a blood vessel diameter of the blood vessel measured by the circulation sensor. A circulatory dynamics measuring device characterized in that blood rheology is obtained using an average blood pressure value calculated using a correction coefficient determined by using the correction coefficient. In the circulatory dynamics measuring device according to any one of claims 1 to 4,
The signal calculation unit, when the average blood pressure value is Pm, the minimum blood pressure value obtained from the blood pressure value is Pd, the maximum blood pressure value is Ps, and the correction coefficient is C,
Pm = Pd + (Ps-Pd) / C
The mean blood pressure value Pm is calculated by the formula represented by
The circulatory dynamics measuring device characterized in that the signal calculation unit obtains blood rheology using a value correlated with the blood flow velocity flowing through a blood vessel in the living body and the average blood pressure value Pm. In the circulatory dynamics measuring device according to any one of claims 1 to 5,
The said signal calculating part calculates | requires a blood rheology by multiplying the reciprocal number of the said average blood pressure value by the value correlated with the said blood flow velocity, The circulatory dynamics measuring apparatus characterized by the above-mentioned. In the circulatory dynamics measuring device according to any one of claims 1 to 6,
The circulatory dynamics measuring device, wherein the circulatory sensor is inside the blood pressure measuring unit.

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