CN110367959A - A kind of blood pressure measuring device based on pulse wave phase difference and pulse wave characteristic parameters - Google Patents

Abstract

The invention proposes a blood pressure measuring device based on pulse wave phase difference and pulse wave characteristic parameters. By designing the pulse wave phase difference signal acquisition module, the device realizes only placing the sensor at the same position of the human body and synchronously collects the pulse wave phase difference and other pulse wave information at the same position, which solves the traditional use of pulse wave arrival time measurement in multiple places on the human body. The portability of the electrocardiogram obtained by attaching the measuring electrodes is poor; the acquisition process of the lower computer is controlled through the upper computer system, and different characteristic parameters of the pulse wave are extracted, and the characteristic parameters, pulse wave phase difference and electronic sphygmomanometer data are gradually regressed The regression equation is obtained through analysis, and subsequent blood pressure measurement can directly use the regression equation and the pulse wave information collected by the pulse wave phase difference signal acquisition module to directly obtain the blood pressure value without stepwise regression analysis. The device can realize continuous measurement of blood pressure, and obtain abundant pulse wave information of different types at the same location.

Description

A blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters

Technical field:

The invention relates to the field of health monitoring of medical equipment, in particular to the field of blood pressure detection, and realizes a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters.

Background technique:

Non-invasive continuous blood pressure measurement is an indirect method of measuring human blood pressure. Compared with invasive measurement, it is more suitable for blood pressure measurement in daily life. Moreover, when non-invasive and continuous blood pressure is measured, a wealth of pulse wave information can be measured, which has important scientific research and clinical value for understanding the influence of external and internal factors on blood pressure, evaluating vascular parameters and preventing cardiovascular diseases. In addition, in China, cardiovascular disease is the number one natural enemy that affects the health of urban and rural residents, and hypertension is an important part of cardiovascular health. According to research estimates, there are currently 270 million people in my country suffering from high blood pressure, and most people have high blood pressure. This is not known. Therefore, the popularization of non-invasive continuous blood pressure monitoring will have positive significance for the control of hypertension and the improvement of national health, and the research on non-invasive continuous blood pressure monitoring technology has important health application value.

Noninvasive continuous blood pressure monitoring using pulse wave arrival time (PAT) has become popular in recent years. PAT is defined as the time difference between the peak R wave of the ECG and the peak point of the peripheral pulse wave. However, using this method will bring a series of disadvantages, firstly because the PAT includes the pre-fire period (PEP), which is determined by the ventricular electromechanical delay (VEMD) and the isovolumic systole period. In addition, the effect of smooth muscle (SM) contraction is not negligible in peripheral arteries, which will affect the relationship between PAT and blood pressure. Moreover, the measurement of the electrocardiogram requires at least two electrodes to be placed on the surface of the human skin, and the electrodes must be connected with wires inevitably, which will affect the convenience of measurement. These shortcomings limit the application and promotion of non-invasive continuous blood pressure measurement technology. In recent studies, non-invasive continuous blood pressure measurement using pulse wave phase difference is expected to improve the above shortcomings. The phase difference (PD) of pulse wave refers to two different types of pulse waves (such as pressure pulse wave and photoplethysmography wave), which propagate from the ventricle to the same position. Due to the difference in the propagation speed of different pulse waves, the peak value will be different A time difference, this time difference is the pulse wave phase difference. However, simply using the pulse wave phase difference for blood pressure measurement will produce large errors. Therefore, if the portability of the non-invasive continuous blood pressure measurement device can be improved, the placement of the sensor measurement on the human body can be reduced, and the pulse wave phase difference based on the pulse wave phase difference can be improved. The purpose of the accuracy of the measuring device can greatly facilitate the application of non-invasive continuous blood pressure measurement based on pulse wave phase difference in the field of blood pressure measurement. The research results can provide a basis for blood pressure measurement based on pulse wave phase difference and pulse wave characteristic parameters. A blood pressure device based on pulse wave phase difference and pulse wave characteristic parameters is formed, and a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters is established on this basis.

Aiming at the problems of poor portability and low accuracy of blood pressure measurement by simply using the pulse wave phase difference when measuring blood pressure based on the PAT principle, it is necessary to attach measuring electrodes to multiple places on the human body to obtain an electrocardiogram. A blood pressure measurement device based on phase difference and pulse wave characteristic parameters aims to reduce the position of electrodes placed on the human body and improve measurement accuracy, thereby improving the portability and accuracy of the device. It is based on pulse wave phase difference and pulse wave characteristic parameters. Provide the basis for blood pressure measurement, and form a blood pressure method based on pulse wave phase difference and pulse wave characteristic parameters. On this basis, establish a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters, which is a non-invasive continuous The promotion and application of blood pressure measurement provide assistance.

Invention content:

Aiming at the problems of poor portability of electrocardiogram obtained by attaching measurement electrodes to multiple places on the human body when using the PAT principle for blood pressure measurement and low accuracy of blood pressure measurement by simply using the pulse wave phase difference, the present invention proposes a pulse wave phase-based The blood pressure measuring device of difference and pulse wave characteristic parameters aims to reduce the position of electrodes placed on the human body and improve the measurement accuracy, thereby improving the portability and accuracy of the device, providing a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters Provide a basis for measurement, and form a blood pressure method based on pulse wave phase difference and pulse wave characteristic parameters, on this basis, establish a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters, which is a non-invasive continuous blood pressure Assist in measurement promotion and application.

A blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters includes pulse wave phase difference signal acquisition module, MCU control module, host computer system, power supply module; described pulse wave phase difference signal acquisition module and MCU control The modules are connected by wires; the MCU control module and the upper computer system are connected by bluetooth; the power supply module is connected with other modules by wires; the purpose of the pulse wave phase difference signal acquisition module is to Two different types of pulse waves are measured at the radial artery of the human body, so that the signals pass through the conditioning circuit; Perform A/D analog-to-digital conversion on different pulse wave signals, and send the converted digital signals to the host computer system via Bluetooth; the host computer system sends control instructions to the MCU control module, thereby controlling the pulse wave phase difference signal acquisition module Work. The host computer system can also store the pulse wave data collected from the pulse wave phase difference signal acquisition module, and extract the pulse wave phase difference, pulse wave characteristic parameters and blood pressure to fit a linear equation; the power supply module A stable voltage source can be provided for the rest of the modules.

Further, the pulse wave phase difference signal acquisition module includes a sensor module and a signal conditioning module. The sensor module includes two different types of sensors, which can simultaneously measure two different types of pulse waves at the radial artery of the human body; preferably, the two different types of sensors are photoelectric sensors and pressure sensors. The two sensors respectively reflect the filling degree of blood and the change of arterial pressure; the signal conditioning module includes a photoelectric pulse wave signal conditioning circuit module and a pressure pulse wave signal conditioning circuit module, and the two pulse wave signal conditioning circuit modules are controlled by a front Composed of an amplifier circuit, a low-pass filter circuit and a secondary amplifier circuit, the function is to amplify the detected pulse wave signal, filter out external high-frequency interference, and achieve a voltage suitable for A/D conversion.

Further, the host computer system sends a collection control command to the MCU control module to control the pulse wave phase difference signal acquisition module to collect two-way pulse waves; the host computer system includes a pulse wave signal preprocessing module , pulse wave waveform storage module, feature point extraction module, feature point storage module, phase difference calculation module, phase difference storage module, stepwise regression analysis module, electronic sphygmomanometer data storage module, regression equation storage module and blood pressure calculation module.

Further, the pulse wave signal preprocessing module is used to process the digital pulse wave signal from the MCU control module, mainly including eliminating special signals, digital filtering and removing baseline drift processing, so as to obtain pulse wave signals with less interference, Prepare for subsequent feature extraction; the pulse wave waveform storage module stores two pulse wave waveform signals processed by the pulse wave signal preprocessing module; the feature point extraction module is used to extract the pulse wave waveform storage The feature quantity of the pulse waveform stored by the module; the feature point storage module is used to store the feature quantity extracted by the feature point extraction module, and is formed with the electronic sphygmomanometer data stored by the electronic sphygmomanometer data storage module One-to-one correspondence; the phase difference calculation module is used to calculate the phase difference between the two pulse wave main wave peak points stored from the feature point storage module; the phase difference storage module is used to store from The phase difference between the two pulse wave main wave peak points calculated by the phase difference calculation module forms a one-to-one correspondence with the electronic sphygmomanometer data stored by the electronic sphygmomanometer data storage module; the step-by-step The regression analysis module analyzes the feature points stored in the feature point storage module and the phase difference stored in the phase difference storage module, and analyzes the linear relationship between the two and the blood pressure value stored in the electronic sphygmomanometer data storage module The regression equation storage module is used to store the regression equation obtained by the stepwise regression analysis module; the electronic sphygmomanometer data storage module is used to store the blood pressure value measured by the electronic sphygmomanometer; the blood pressure calculation module is used for Using the linear equation stored from the regression equation storage module, the pulse wave feature points stored from the feature point storage module and the pulse wave phase difference value stored from the phase difference storage module, the latter two data are substituted into the former Among them, the blood pressure can be measured.

Further, the pulse wave characteristic quantity includes pulse wave systolic relative time T1t=T1/T, systolic and diastolic time ratio T12=T1/T2, dicrotic wave time relative time Tft=Tf/T, pulse wave Main peak height H, descending isthmus height h, dicrotic wave height g, descending isthmus relative height Hh=h/H, dicrotic wave relative height Hg=g/H, systolic relative area S1S=S1/(S1+S2 ), the time ratio of systole and diastole S12=S1/S2, the main peak rise rate V, the characteristic value K and the cardiac output per stroke Z. in P _d is the value corresponding to the valley point of the pulse wave, P _s is the value corresponding to the peak point of the pulse wave, and P _m represents the average value of the pulse wave. The cardiac output Z per stroke is defined as Z=H(1+T12). H represents the main peak height of the pulse wave, and T12 represents the time ratio between systole and diastole.

Further, the described stepwise regression analysis can obtain the equation shown in the basic form as follows:

y＝a ₀ +a ₁ ×x ₁ +a ₂ ×x ₂ +...+a _n ×x _n

where y is the dependent variable, namely systolic and diastolic blood pressure. a ₀ is a constant term, and a ₁ , a ₂ ... a _n are partial regression coefficients. x ₁ , x ₂ ... x _n are independent variables, that is, characteristic parameters of PD and pulse wave.

The present invention further provides a method for using the device, comprising the following steps:

Step 1: Acquisition of two different types of pulse waves and measurement of electronic sphygmomanometer

Step 11: Wear the pulse wave phase difference signal acquisition module on the inner radial artery of the right hand, and use the host computer system to send an acquisition control command to the MCU control module;

Step 12: The MCU control module controls the sensor module in the pulse wave phase difference signal acquisition module to start collecting two different types of pulse waves;

Step 13: Amplify and filter the two-way pulse wave signal through the signal conditioning circuit module, and transmit the processed two-way pulse wave signal of different types to the MCU control module;

Step 14: The MCU control module performs A/D analog-to-digital conversion on the two-way pulse wave signal obtained by the pulse wave phase difference signal acquisition module, and sends the converted digital signal to the pulse wave in the host computer system via Bluetooth. In the signal preprocessing module;

Step 2: Processing of two different types of pulse wave signals

Step 21: Use the pulse wave signal preprocessing module in the host computer system to process the digital pulse wave signal from the MCU control module, mainly including eliminating special signals, digital filtering and removing baseline drift, and storing in the host Pulse wave waveform storage module in computer system;

Step 22: Use the feature point extraction module to extract the feature quantity of the pulse wave stored in the pulse wave waveform storage module;

Step 23: Use the feature point storage module to store the pulse wave feature quantity in the feature point extraction module, and form a one-to-one correspondence with the electronic sphygmomanometer data stored in the electronic sphygmomanometer data storage module;

Step 24: using the phase difference calculation module to calculate the phase difference between the two pulse wave main wave peak points stored in the feature point storage module;

Step 25: Use the phase difference storage module to store the phase difference data in the phase difference calculation module, and form a one-to-one correspondence with the electronic sphygmomanometer data stored in the electronic sphygmomanometer data storage module;

Step 26: Use the stepwise regression analysis module to analyze the feature points stored in the feature point storage module and the phase difference stored in the phase difference storage module, and analyze the relationship between the two and the electronic sphygmomanometer data storage The linear relationship between the blood pressure values stored in the module, and the obtained regression equation is stored in the regression equation storage module for subsequent use. Furthermore, the stepwise regression analysis module needs to be used only when using the invention for the first time;

Step 27: Use the blood pressure calculation module to use the linear equation analyzed from the stepwise regression analysis module, the pulse wave characteristics stored from the feature point storage module and the pulse wave stored from the phase difference storage module By substituting the latter two data into the former, the blood pressure can be continuously measured in the following time;

Step 3: Calibration

The present invention also provides a calibration method, which is used to improve the measurement accuracy of long-term continuous blood pressure measurement using the device, and determines the number of independent variables of the equation stored in the regression equation storage module to determine the number of steps to repeat step 1 and step 21 to step 25. The number of times to be repeated is the number of independent variables plus one. In addition, since the blood pressure of the human body is relatively stable for a period of time, the present invention adopts the method of changing the breathing rate, that is, changing the breathing rate when using an electronic sphygmomanometer to measure the blood pressure, to change the physiological state of the human body, so as to achieve as much as possible in a relatively short period of time. Obtain more different blood pressure and two-way pulse wave data of the human body.

Step 31: Repeat Step 21 to Step 25 in a steady breathing state;

Step 32: After resting for one minute, repeat steps 21 to 25 while changing the breathing rate;

Step 33: Rest for another minute and repeat steps 21 to 25 while changing the breathing rate again. Until the number of repetitions is equal to the number of independent variables plus one.

The beneficial effects of the present invention are as follows:

1. A blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters proposed by the present invention has the advantages of strong portability, simple structure and high practical value, which is conducive to the promotion of non-invasive continuous blood pressure measurement technology.

2. A blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters proposed by the present invention can simultaneously measure two different types of pulse waves at the same site, and obtain a large amount of pulse wave information, which is beneficial for future analysis of different pulse waves Characteristic differences between waves.

3. A blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters proposed by the present invention uses pulse wave phase difference and pulse wave characteristic parameters to calculate blood pressure, which is beneficial to improve the accuracy of the calculated blood pressure.

Description of drawings:

Fig. 1 is a schematic diagram of a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters according to the present invention

Fig. 2 is a schematic diagram of modules included in the upper computer system of the present invention

Fig. 3 is a schematic diagram of modules included in the pulse wave phase difference signal acquisition module of the present invention

Fig. 4 is a schematic diagram of the pulse wave feature quantity according to the present invention

Detailed ways:

With reference to accompanying drawing, further illustrate the present invention:

Aiming at the problems of poor portability of electrocardiogram obtained by attaching measurement electrodes to multiple places on the human body when using the PAT principle for blood pressure measurement and low accuracy of blood pressure measurement by simply using the pulse wave phase difference, the present invention proposes a pulse wave phase-based The blood pressure measuring device of difference and pulse wave characteristic parameters aims to reduce the position of electrodes placed on the human body and improve the measurement accuracy, thereby improving the portability and accuracy of the device, providing a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters Provide a basis for measurement, and form a blood pressure method based on pulse wave phase difference and pulse wave characteristic parameters, on this basis, establish a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters, which is a non-invasive continuous blood pressure Assist in measurement promotion and application.

The present invention first proposes a blood pressure measurement device based on pulse wave phase difference signal and pulse wave characteristic parameters, as shown in Figure 1, including pulse wave phase difference signal acquisition module, MCU control module, host computer system, power supply module; The pulse wave phase difference signal acquisition module and the MCU control module are connected by wires; the MCU control module and the upper computer system are connected by bluetooth; the power supply module is connected with the remaining modules by wires; The purpose of the pulse wave phase difference signal acquisition module is to measure two different types of pulse waves at the radial artery of the human body at the same time, so that the signals pass through the conditioning circuit; the MCU control module accepts control instructions from the host computer system, and Carry out A/D analog-to-digital conversion to two different pulse wave signals obtained by the pulse wave phase difference signal acquisition module respectively, and send the converted digital signal to the host computer system via bluetooth; the host computer system sends control instructions to The MCU controls the module to control the pulse wave phase difference signal acquisition module to work. The host computer system can also store the pulse wave data collected from the pulse wave phase difference signal acquisition module, and extract the pulse wave phase difference, pulse wave characteristic parameters and blood pressure to fit a linear equation; the power supply module A stable voltage source can be provided for the rest of the modules.

Further, the pulse wave phase difference signal acquisition module is shown in FIG. 3 , which specifically includes a sensor module and a signal conditioning module. The sensor module includes two different types of sensors, which can simultaneously measure two different types of pulse waves at the radial artery of the human body; preferably, the two different types of sensors are photoelectric sensors and pressure sensors. The two sensors respectively reflect the filling degree of blood and the change of arterial pressure; the signal conditioning module includes a photoelectric pulse wave signal conditioning circuit module and a pressure pulse wave signal conditioning circuit module, and the two pulse wave signal conditioning circuit modules are controlled by a front Composed of an amplifier circuit, a low-pass filter circuit and a secondary amplifier circuit, the function is to amplify the detected pulse wave signal, filter out external high-frequency interference, and achieve a voltage suitable for A/D conversion.

Further, the host computer system is shown in FIG. 2 . The upper computer system sends acquisition control instructions to the MCU control module to control the pulse wave phase difference signal acquisition module to collect two-way pulse waves; the upper computer system includes a pulse wave signal preprocessing module, a pulse wave waveform storage module, feature point extraction module, feature point storage module, phase difference calculation module, phase difference storage module, stepwise regression analysis module, electronic sphygmomanometer data storage module, regression equation storage module and blood pressure calculation module.

Further, the pulse wave signal preprocessing module is used to process the digital pulse wave signal from the MCU control module, mainly including eliminating special signals, digital filtering and removing baseline drift processing, so as to obtain pulse wave signals with less interference, Prepare for subsequent feature extraction; the pulse wave waveform storage module stores two pulse wave waveform signals processed by the pulse wave signal preprocessing module; the feature point extraction module is used to extract the pulse wave waveform storage The feature quantity of the pulse waveform stored by the module; the feature point storage module is used to store the feature quantity extracted by the feature point extraction module, and is formed with the electronic sphygmomanometer data stored by the electronic sphygmomanometer data storage module One-to-one correspondence; the phase difference calculation module is used to calculate the phase difference between the two pulse wave main wave peak points stored from the feature point storage module; the phase difference storage module is used to store from The phase difference between the two pulse wave main wave peak points calculated by the phase difference calculation module forms a one-to-one correspondence with the electronic sphygmomanometer data stored by the electronic sphygmomanometer data storage module; the step-by-step The regression analysis module analyzes the feature points stored in the feature point storage module and the phase difference stored in the phase difference storage module, and analyzes the linear relationship between the two and the blood pressure value stored in the electronic sphygmomanometer data storage module The regression equation storage module is used to store the regression equation obtained by the stepwise regression analysis module; the electronic sphygmomanometer data storage module is used to store the blood pressure value measured by the electronic sphygmomanometer; the blood pressure calculation module is used for Using the linear equation stored from the regression equation storage module, the pulse wave feature points stored from the feature point storage module and the pulse wave phase difference value stored from the phase difference storage module, the latter two data are substituted into the former Among them, the blood pressure can be measured.

Further, the pulse wave feature quantity is shown in Figure 4, including pulse wave systolic relative time T1t=T1/T, systolic and diastolic time ratio T12=T1/T2, dicrotic wave time relative time Tft= Tf/T, pulse wave main peak height H, descending isthmus height h, dicrotic wave height g, descending isthmus relative height Hh=h/H, dicrotic wave relative height Hg=g/H, systolic relative area S1S= S1/(S1+S2), time ratio of systole and diastole S12=S1/S2, main peak rise rate V=CC'/BC', characteristic value K and cardiac output per stroke Z. in P _d is the corresponding value of the pulse wave trough point, which is the ordinate of the B point in Fig. 4, and P _s is the corresponding value of the pulse wave peak point, which is the ordinate of the C point shown in Fig. 4, and P _m represents the average value, is the value obtained by dividing the integral value from B to B' in Figure 4 by the period. The cardiac output Z per stroke is defined as Z=H(1+T12). H represents the main peak height of the pulse wave, and T12 represents the time ratio between systole and diastole.

Further, the described stepwise regression analysis can obtain the equation shown in the basic form as follows:

y＝a ₀ +a ₁ ×x ₁ +a ₂ ×x ₂ +...+a _n ×x _n

where y is the dependent variable, namely systolic and diastolic blood pressure. a ₀ is a constant term, and a ₁ , a ₂ ... a _n are partial regression coefficients. x ₁ , x ₂ ... x _n are independent variables, that is, characteristic parameters of PD and pulse wave.

The present invention further provides a method for using the device, comprising the following steps:

Step 1: Acquisition of two different types of pulse waves and measurement of electronic sphygmomanometer

Step 11: Wear the pulse wave phase difference acquisition module on the medial radial artery of the right hand, and use the host computer system to send an acquisition control command to the MCU control module;

Step 12: the MCU control module controls the sensor module in the pulse wave phase difference acquisition module to start collecting two different types of pulse waves;

Step 13: Amplify and filter the two-way pulse wave signal through the signal conditioning circuit module, and transmit the processed two-way pulse wave signal of different types to the MCU control module;

Step 14: The MCU control module performs A/D analog-to-digital conversion on the two-way pulse wave signal obtained by the pulse wave phase difference acquisition module, and sends the converted digital signal to the pulse wave signal in the host computer system via Bluetooth In the preprocessing module;

Step 2: Processing of two different types of pulse wave signals

Step 21: Use the pulse wave signal preprocessing module in the host computer system to process the digital pulse wave signal from the MCU control module, mainly including eliminating special signals, digital filtering and removing baseline drift, and storing in the host Pulse wave waveform storage module in computer system;

Step 22: Use the feature point extraction module to extract the feature quantity of the pulse wave stored in the pulse wave waveform storage module;

Step 23: Use the feature point storage module to store the pulse wave feature quantity in the feature point extraction module, and form a one-to-one correspondence with the electronic sphygmomanometer data stored in the electronic sphygmomanometer data storage module;

Step 24: using the phase difference calculation module to calculate the phase difference between the two pulse wave main wave peak points stored in the feature point storage module;

Step 25: Use the phase difference storage module to store the phase difference data in the phase difference calculation module, and form a one-to-one correspondence with the electronic sphygmomanometer data stored in the electronic sphygmomanometer data storage module;

Step 26: Use the stepwise regression analysis module to analyze the feature points stored in the feature point storage module and the phase difference stored in the phase difference storage module, and analyze the relationship between the two and the electronic sphygmomanometer data storage The linear relationship between the blood pressure values stored in the module, and the obtained regression equation is stored in the regression equation storage module for subsequent use. Furthermore, the stepwise regression analysis module needs to be used only when using the invention for the first time;

Step 27: Use the blood pressure calculation module to use the linear equation analyzed from the stepwise regression analysis module, the pulse wave characteristics stored from the feature point storage module and the pulse wave stored from the phase difference storage module By substituting the latter two data into the former, the blood pressure can be continuously measured in the following time;

Step 3: Calibration

The present invention also provides a calibration method, which is used to improve the measurement accuracy of long-term continuous blood pressure measurement using the device, and determines the number of independent variables of the equation stored in the regression equation storage module to determine the number of steps to repeat step 1 and step 21 to step 25. The number of times to be repeated is the number of independent variables plus one. In addition, since the blood pressure of the human body is relatively stable for a period of time, the present invention adopts the method of changing the breathing rate, that is, changing the breathing rate when using an electronic sphygmomanometer to measure the blood pressure, to change the physiological state of the human body, so as to achieve as much as possible in a relatively short period of time. Obtain more different blood pressure and two-way pulse wave data of the human body;

Step 31: Repeat Step 21 to Step 25 in a steady breathing state;

Step 32: After resting for one minute, repeat steps 21 to 25 while changing the breathing rate;

Step 33: Rest for another minute and repeat steps 21 to 25 while changing the breathing rate again. Until the number of repetitions is equal to the number of independent variables plus one.

For example, if the obtained regression equation is y=a ₀ +a ₁ ×PD+a ₂ ×K, the systolic blood pressure measured by an electronic sphygmomanometer in a steady breathing state is 110mmHg, and the systolic blood pressure is 76mmHg. The PD measured by the device is 50ms, and the K measured using the device of the present invention is 0.54, then it can be obtained

110＝a ₀ +a ₁ ×50+a ₂ ×0.54

76＝a ₀ ^* +a ₁ ^* ×50+a ₂ ^* ×0.54

If the systolic blood pressure measured by the electronic sphygmomanometer is 120mmHg after changing the respiratory rate for the first time, the systolic blood pressure is 80mmHg, the PD measured by the device of the present invention is 46ms, and the K measured by the device of the present invention is 0.50, then available

120＝a ₀ +a ₁ ×46+a ₂ ×0.50

80＝a ₀ ^* +a ₁ ^* ×46+a ₂ ^* ×0.50

If the systolic blood pressure measured by the electronic sphygmomanometer is 130mmHg after changing the respiratory rate for the second time, the systolic blood pressure is 86mmHg, the PD measured by the device of the present invention is 40ms, and the K measured by the device of the present invention is 0.45, then available

130＝a ₀ +a ₁ ×40+a ₂ ×0.45

86＝a ₀ ^* +a ₁ ^* ×40+a ₂ ^* ×0.45

Each coefficient can be obtained by solving the above equation.

The content described in the embodiments of this specification is only an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms stated in the embodiments. Equivalent technical means that a person can think of based on the concept of the present invention.

Claims (4)

1. A blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameter, is characterized in that comprising: pulse wave phase difference signal acquisition module, MCU control module, upper computer system, power supply module; Described pulse wave phase The difference signal acquisition module and the MCU control module are connected by wires; the MCU control module and the upper computer system are connected by bluetooth; the power supply module is connected with the remaining modules by wires; the pulse wave phase difference The signal acquisition module measures two different types of pulse waves at the radial artery of the human body at the same time, so that the signals pass through the conditioning circuit; the MCU control module accepts control instructions from the upper computer system, and respectively transmits the pulse wave phase difference to the signal acquisition module The obtained two different pulse wave signals are subjected to A/D analog-to-digital conversion, and the converted digital signal is sent to the host computer system via Bluetooth; the host computer system sends control instructions to the MCU control module, thereby controlling the pulse wave phase The difference signal acquisition module works; the host computer system can also store the pulse wave data collected from the pulse wave phase difference signal acquisition module, and extract the pulse wave phase difference, pulse wave characteristic parameters and blood pressure to fit a linear equation; The power supply module can provide a stable voltage source for the remaining modules; the pulse wave phase difference signal acquisition module includes a sensor module and a signal conditioning module; the sensor module includes two different types of sensors, which can simultaneously Two different types of pulse waves are measured at the radial artery of the human body; the signal conditioning module includes a photoelectric pulse wave signal conditioning circuit module and a pressure pulse wave signal conditioning circuit module, and the two pulse wave signal conditioning circuit modules are preamplified circuit, a low-pass filter circuit and a secondary amplifier circuit, which will amplify the detected pulse wave signal, filter out external high-frequency interference at the same time, and achieve a voltage suitable for A/D conversion; the host computer system Including pulse wave signal preprocessing module, pulse wave waveform storage module, feature point extraction module, feature point storage module, phase difference calculation module, phase difference storage module, stepwise regression analysis module, electronic sphygmomanometer data storage module, regression equation storage module and a blood pressure calculation module; the pulse wave signal preprocessing module is used to process the digital pulse wave signal from the MCU control module, mainly including eliminating special signals, digital filtering and removing baseline drift processing; the pulse wave waveform storage module stores Two pulse wave waveform signals processed by the pulse wave signal preprocessing module; the feature point extraction module extracts the feature quantity of the pulse wave waveform stored in the pulse wave waveform storage module; the feature point storage module stores the The feature quantity extracted by the feature point extraction module described above forms a one-to-one correspondence with the electronic sphygmomanometer data stored in the electronic sphygmomanometer data storage module; The phase difference between the stored two-way pulse wave main wave peak points; the phase difference storage module stores the phase difference between the two pulse wave main wave peak points calculated from the phase difference calculation module, and with The electronic The electronic sphygmomanometer data stored in the sphygmomanometer data storage module forms a one-to-one correspondence; the stepwise regression analysis module analyzes the feature points stored in the feature point storage module and the phase difference stored in the phase difference storage module, and analyzes The linear relationship between the two and the blood pressure value stored in the electronic sphygmomanometer data storage module; the regression equation stored in the stepwise regression analysis module in the described regression equation storage module; The blood pressure value measured by the electronic sphygmomanometer; the blood pressure calculation module uses the linear equation stored from the regression equation storage module, the pulse wave feature point stored from the feature point storage module and the phase difference storage module stored Blood pressure can be measured by substituting the latter two data into the former. 2. A blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters as claimed in claim 1, characterized in that: the host computer system sends acquisition control instructions to the MCU control module, and the control unit The pulse wave phase difference signal acquisition module described above collects two-way pulse waves. 3. A kind of blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameter as claimed in claim 1, it is characterized in that: described pulse wave characteristic quantity comprises pulse wave systolic phase relative time T1t=T1/T, The time ratio of systole and diastole T12=T1/T2, the relative time of dicrotic wave time Tft=Tf/T, the main peak height of pulse wave H, the height of descending isthmus h, the height of dicrotic wave g, the relative height of descending isthmus Hh =h/H, relative height of dicrotic wave Hg=g/H, relative area of systole S1S=S1/(S1+S2), time ratio of systole and diastole S12=S1/S2, main peak rising rate V, characteristic K value and cardiac output per stroke Z; where P _d is the corresponding value of the pulse wave trough point, P _s is the corresponding value of the pulse wave peak point, P _m represents the average value of the pulse wave; the cardiac output per stroke Z is defined as Z=H(1+T12); H represents the pulse wave The height of the main peak, T12 represents the time ratio between systole and diastole. 4. A method of blood pressure measurement based on pulse wave phase difference and pulse wave characteristic parameters, using a blood pressure measurement device based on pulse wave phase difference and pulse wave characteristic parameters as claimed in claim 1, characterized in that it comprises the following step: Step 1: Acquisition of two different types of pulse waves and measurement of electronic sphygmomanometer Step 11: Wear the pulse wave phase difference signal acquisition module on the inner radial artery of the right hand, and use the host computer system to send an acquisition control command to the MCU control module; Step 12: The MCU control module controls the sensor module in the pulse wave phase difference signal acquisition module to start collecting two different types of pulse waves; Step 13: Amplify and filter the two-way pulse wave signal through the signal conditioning circuit module, and transmit the processed two-way pulse wave signal of different types to the MCU control module; Step 14: The MCU control module performs A/D analog-to-digital conversion on the two-way pulse wave signal obtained by the pulse wave phase difference signal acquisition module, and sends the converted digital signal to the pulse wave in the host computer system via Bluetooth. In the signal preprocessing module; Step 2: Processing of two different types of pulse wave signals Step 21: Use the pulse wave signal preprocessing module in the host computer system to process the digital pulse wave signal from the MCU control module, mainly including eliminating special signals, digital filtering and removing baseline drift, and storing in the host Pulse wave waveform storage module in computer system; Step 22: Use the feature point extraction module to extract the feature quantity of the pulse wave stored in the pulse wave waveform storage module; Step 23: Use the feature point storage module to store the pulse wave feature quantity in the feature point extraction module, and form a one-to-one correspondence with the electronic sphygmomanometer data stored in the electronic sphygmomanometer data storage module; Step 24: using the phase difference calculation module to calculate the phase difference between the two pulse wave main wave peak points stored in the feature point storage module; Step 25: Use the phase difference storage module to store the phase difference data in the phase difference calculation module, and form a one-to-one correspondence with the electronic sphygmomanometer data stored in the electronic sphygmomanometer data storage module; Step 26: Use the stepwise regression analysis module to analyze the feature points stored in the feature point storage module and the phase difference stored in the phase difference storage module, and analyze the relationship between the two and the electronic sphygmomanometer data storage The linear relationship between the blood pressure values stored in the module, and the obtained regression equation is stored in the regression equation storage module for subsequent use; The described stepwise regression analysis can obtain the regression equation of basic form as follows: y＝a ₀ +a ₁ ×x ₁ +a ₂ ×x ₂ +...+a _n ×x _n Among them, y is the dependent variable, that is, systolic blood pressure and diastolic blood pressure; a ₀ is a constant item, a ₁ , a ₂ ... a _n are partial regression coefficients; x ₁ , x ₂ ... x _n are independent variables, That is, PD and pulse wave characteristic parameters; in addition, only need to use stepwise regression analysis module when using the present invention for the first time; Step 27: Use the blood pressure calculation module to use the linear equation analyzed from the stepwise regression analysis module, the pulse wave feature points stored from the feature point storage module and the pulse stored from the phase difference storage module By substituting the latter two data into the former, the blood pressure can be continuously measured in the following time; Step 3: Calibration A calibration method, used to improve the measurement accuracy of long-term continuous blood pressure measurement using the device, according to the number of independent variables of the equation stored in the regression equation storage module, to determine the number of times to repeat step 1 and step 21 to step 25, need to repeat The number of times is the number of independent variables plus one; in addition, because the blood pressure of the human body is relatively stable within a period of time, the present invention adopts the method of changing the respiratory rate, that is, changing the respiratory rate when using an electronic sphygmomanometer to measure blood pressure, to change the physiological state of the human body, thereby Obtain as much blood pressure and two-way pulse wave data as possible in a relatively short period of time; Step 31: Repeat Step 21 to Step 25 in a steady breathing state; Step 32: After resting for one minute, repeat steps 21 to 25 while changing the breathing rate; Step 33: Take a rest for another minute, and repeat steps 21 to 25 while changing the breathing rate again; until the number of repetitions and the number of independent variables add one.