A high-precision, rapid, non-invasive blood pressure measurement method and device

Abstract

The present invention relates to a high-precision, rapid, non-invasive blood pressure measurement method and device. This method continuously measures pulse waves, applies varying static pressure to the measurement site during the measurement process, obtains a measured pulse wave, extracts characteristic variables used to calculate blood pressure based on the measured pulse wave, and obtains blood pressure measurement results based on a blood pressure calculation model. The measurement device includes a cuff equipped with an airbag, a probe, and a host computer. The host computer controls the operation of the airbag inflation and deflation device and the probe to achieve the blood pressure measurement described above. The present invention can conveniently, rapidly, and accurately achieve blood pressure measurement.

Description

Technical Field

[0001] The present invention relates to a high-precision, rapid, non-invasive blood pressure measurement method and device, belonging to the technical field of non-invasive blood pressure measurement. Background Art

[0002] Blood pressure refers to the lateral pressure exerted by blood on the blood vessel wall when flowing in the blood vessels. It is an important physiological indicator reflecting cardiovascular function. It can be combined with other physiological indicators and diagnostic methods to judge related health and disease conditions. It is of great significance in disease diagnosis, observation of treatment effects, prognosis judgment and health management.

[0003] Existing blood pressure measurement methods can be broadly categorized into two main categories: invasive direct measurement and non-invasive indirect measurement. While invasive direct measurement provides the most accurate blood pressure data, it is technically demanding and somewhat invasive, making it suitable only for critically ill patients undergoing emergency treatment or major surgery. Indirect measurement, on the other hand, indirectly measures blood pressure by measuring parameters such as arterial wall pulsation and changes in vascular volume. Due to its simplicity and ease of use, indirect measurement methods are widely used in clinical practice.

[0004] Indirect blood pressure measurement methods can be further divided into two categories: intermittent and continuous. Continuous blood pressure measurement methods mainly include arterial tension, volume compensation, pulse wave velocity or pulse wave transit time, and pulse wave characteristic parameter determination.

[0005] The arterial tension method requires the sensor to have high sensitivity to displacement and pressure. The sensor must be pressed tightly against the artery close to the bone and the sensor measurement position must be kept relatively fixed. When the physiological state of the subject changes, measurement errors may occur due to inconsistencies between the external force and the change in mean pressure.

[0006] Volume compensation methods can be broadly categorized into two types: measurement based on external pressure applied by a balloon and fingertip measurement using photoelectric recording. While simple to use, continuous blood pressure measurement using a balloon pressurizes the arteries. However, the constant pressure from the balloon can cause venous congestion over time, causing discomfort for the subject. Fingertip blood pressure measurement using photoelectric recording can be subject to significant signal interference, instability, and low accuracy. Furthermore, the long-term application of a preset reference pressure can cause discomfort and compromise measurement accuracy.

[0007] Compared to arterial tension methods, pulse wave velocity or pulse wave transit time measurement requires less sensor positioning and is less uncomfortable. However, modeling the relationship between pulse wave velocity or transit time and blood pressure is complex, exhibits significant individual variability, and is challenging.

[0008] The pulse wave characteristic parameter measurement method estimates blood pressure by analyzing the characteristic parameters of the pulse wave. To identify the different characteristic parameters of the pulse wave, it requires complex signal processing and algorithms, as well as a large amount of data training and verification. Its accuracy and reliability vary among different populations.

[0009] Due to the unique characteristics of these existing technologies, they are suitable for their respective occasions and can obtain measurement data with corresponding accuracy, but they also have certain limitations. Therefore, it is necessary to develop a measurement method that is convenient and practical and can meet higher precision requirements. Summary of the Invention

[0010] The purpose of the present invention is to achieve blood pressure measurement conveniently, quickly and with high accuracy.

[0011] The technical solution of the present invention is: a high-precision, rapid, non-invasive blood pressure measurement method, which continuously performs pulse wave measurement and applies a changing static pressure to the measurement site during the measurement process to obtain a measured pulse wave. Based on the measured pulse wave, characteristic variables for calculating blood pressure are extracted, and the blood pressure measurement results are obtained according to a blood pressure calculation model.

[0012] The function expression of the blood pressure calculation model can usually be a linear function, and can also be a nonlinear function when necessary.

[0013] Preferably, the blood pressure calculation model can be constructed according to the following method:

[0014] i) Pulse wave measurement: Continuously measure the arterial pulse wave. During the measurement process, control the static pressure to increase in steps with a certain jump amplitude to form two or more static pressure states. In each static pressure state (static pressure value), measure no less than one pulse wave (a complete pulse wave). The maximum static pressure value is preferably lower than the static pressure value that can block blood flow;

[0015] ii) Pulse wave normalization: The pulse wave obtained under one of the static pressure states (e.g., the set maximum static pressure state, or a static pressure state lower than the maximum static pressure) is subjected to pulse rate normalization and amplitude normalization to form a normalized pulse wave. This is used as the reference pulse wave. The pulse waves obtained under other static pressure states are normalized relative to the reference pulse wave to form a relatively normalized normalized pulse wave.

[0016] For example, a normalized pulse rate and a normalized amplitude are set, the pulse rates of all pulse waves are normalized to the set normalized pulse rate, and the amplitude of the pulse wave used as a reference is normalized to the set normalized amplitude, thereby forming a reference pulse wave; the amplitude of the pulse wave not used as a reference is normalized according to the normalization coefficient of the pulse wave used as a reference, wherein the pulse wave used as a reference is the pulse wave at the maximum static pressure value;

[0017] iii) Constructing sample data: Extract the characteristic parameters of the normalized pulse wave, measure the corresponding blood pressure (blood pressure of the same subject), calculate the rate of change of the characteristic parameters under adjacent static pressure states, use the characteristic parameter change rate as the model input data, and the blood pressure as the model output data, to form a sample data;

[0018] iv) Constructing a blood pressure calculation model: Selecting a function expression for the blood pressure calculation model and fitting it with a number of sample data to form a blood pressure calculation model.

[0019] The characteristic parameter may be any one or more (including all) of the following characteristic parameters: changes in the normalized pulse wave amplitude under different static pressure states, changes in the area under the normalized pulse curve, changes in the duration of the normalized pulse wave rising edge, and changes in the slope of the normalized pulse wave rising edge from the starting point to the maximum amplitude point.

[0020] Preferably, the blood pressure calculation model can be constructed according to the following method:

[0021] i) Pulse wave measurement: Continuously perform photoplethysmography measurements. During the measurement process, control the static pressure to increase in steps with a certain jump amplitude to form two or more static pressure states. At each static pressure state (static pressure value), measure at least one pulse wave (a complete pulse wave). The maximum static pressure value is preferably lower than the static pressure value that can block blood flow. The static pressure value in the initial stage is zero.

[0022] ii) Pulse wave normalization: Pulse waves measured under one static pressure state (e.g., the set maximum static pressure state, or a static pressure state lower than the maximum static pressure) are subjected to pulse rate normalization and amplitude normalization to form a normalized pulse wave. This is used as the baseline pulse wave. Pulse waves measured under other static pressure states are normalized relative to the baseline pulse wave to form relatively normalized normalized pulse waves.

[0023] For example, a normalized pulse rate and a normalized amplitude are set, the pulse rates of all pulse waves are normalized to the set normalized pulse rate, and the amplitude of the pulse wave used as a reference is normalized to the set normalized amplitude, thereby forming a reference pulse wave; the amplitude of the pulse wave not used as a reference is normalized according to the normalization coefficient of the pulse wave used as a reference, wherein the pulse wave used as a reference is a pulse wave under zero static pressure;

[0024] iii) Constructing sample data: Extract the characteristic parameters of the normalized pulse wave, measure the corresponding blood pressure (blood pressure of the same subject), calculate the rate of change of the characteristic parameters under adjacent static pressure states, use the characteristic parameter change rate as the model input data, and the blood pressure as the model output data, to form a sample data;

[0025] iv) Constructing a blood pressure calculation model: Selecting a function expression for the blood pressure calculation model and fitting it with a number of sample data to form a blood pressure calculation model.

[0026] The characteristic parameter may be any one or more (including all) of the following characteristic parameters: change in amplitude of the normalized pulse wave under different static pressure states, change in area under the normalized pulse curve, change in duration of the rising edge of the normalized pulse wave, and change in slope of the rising edge of the normalized pulse wave from the starting point to the maximum amplitude point.

[0027] Preferably, the blood pressure calculation model can be constructed according to the following method:

[0028] i) Pulse wave measurement: Continuously measure the arterial pulse wave. During the measurement process, control the static pressure to increase uniformly from zero static pressure to the maximum static pressure (the set maximum static pressure) at a certain speed. The maximum static pressure value is preferably lower than the static pressure value that can block blood flow. Measure and obtain several pulse waves;

[0029] ii) Constructing a pulse wave envelope curve: constructing a pulse wave envelope curve based on each pulse wave obtained by measurement;

[0030] iii) Envelope curve normalization: performing amplitude normalization operation on the envelope curve to form a normalized envelope curve;

[0031] For example, a normalized amplitude is set, and the envelope curve value (amplitude) corresponding to a certain static pressure (for example, a set maximum static pressure, or, when appropriate, zero static pressure or a static pressure between zero static pressure and the maximum static pressure) on the envelope curve is normalized to the set normalized amplitude, and a corresponding normalization coefficient is recorded. The entire envelope curve is normalized using the normalization coefficient to form a normalized envelope curve that changes with static pressure;

[0032] iv) Constructing sample data: Extract the characteristic parameters of the normalized envelope curve, measure the corresponding blood pressure (blood pressure of the same subject), use the characteristic parameters as model input data, and blood pressure as model output data to form a sample data;

[0033] v) Construct a blood pressure calculation model: Select a function expression for the blood pressure calculation model and use a number of sample data for fitting to form a blood pressure calculation model.

[0034] The characteristic parameter may be any one or more (including all) of the following characteristic parameters: the change in the slope of the line between the reference point and the maximum static pressure point (the point where the static pressure value is the maximum static pressure value), the amplitude ratio of the maximum static pressure point to the reference point, and the static pressure value of the point with an amplitude of 1 / 2 (one half) of the amplitude of the maximum static pressure point, wherein the reference point is located between the zero static pressure point and the maximum static pressure point.

[0035] Preferably, the blood pressure calculation model can be constructed according to the following method:

[0036] i) Pulse wave measurement: Continuously perform photoplethysmography measurements. During the measurement process, control the static pressure to increase uniformly from zero static pressure to a maximum static pressure (the set maximum static pressure value) at a certain speed. The maximum static pressure value is preferably lower than the static pressure value that can block blood flow. Measure and obtain several pulse waves. Before the static pressure increases uniformly, perform or do not perform a pulse wave measurement at zero static pressure. The pulse wave measurement at zero static pressure and the pulse wave measurement at a uniformly increasing static pressure are performed continuously.

[0037] ii) Constructing a pulse wave envelope curve: constructing a pulse wave envelope curve based on each pulse wave obtained by measurement;

[0038] iii) Envelope curve normalization: performing amplitude normalization operation on the envelope curve to form a normalized envelope curve;

[0039] For example, a normalized amplitude is set, and the envelope curve value (amplitude) corresponding to a certain static pressure (for example, zero static pressure, or, when appropriate, the maximum static pressure or a static pressure between zero static pressure and the maximum static pressure) on the envelope curve is normalized to the set normalized amplitude, and the corresponding normalization coefficient is recorded. The normalization operation is performed on the entire envelope curve using the normalization coefficient to form a normalized envelope curve that changes with the static pressure;

[0040] iv) Constructing sample data: Extract the characteristic parameters of the normalized envelope curve, measure the corresponding blood pressure (blood pressure of the same subject), use the characteristic parameters as model input data, and blood pressure as model output data to form a sample data;

[0041] v) Construct a blood pressure calculation model: Select a function expression for the blood pressure calculation model and use a number of sample data for fitting to form a blood pressure calculation model.

[0042] The characteristic parameter can be any one or more (including all) of the following characteristic parameters: the slope of the line between the reference point and the maximum static pressure point (the point where the static pressure value is the maximum static pressure value), the amplitude ratio of the maximum static pressure point to the reference point, and the static pressure value at the point with the maximum slope, and the reference point is located between the zero static pressure point and the maximum static pressure point.

[0043] A high-precision, rapid, non-invasive blood pressure measurement device can be used to perform blood pressure measurement using any of the high-precision, rapid, non-invasive blood pressure measurement methods disclosed in the present invention, including:

[0044] A cuff, for being worn on (e.g., tied to) a measured part, provided with an air bag for applying static pressure to the measured part, the air bag being provided with an inflation and deflation device, the inflation and deflation device comprising an inflation pump for inflation and an inflation valve for controlling deflation;

[0045] A probe (sensor) for measuring the pulse wave of the measured part, wherein the probe may be a probe for measuring arterial pulse waves and / or a probe for measuring photoplethysmography;

[0046] The host is used to control and coordinate the operation of the inflation and deflation device and the probe, enter the blood pressure measurement working mode according to the external input blood pressure measurement command, control the probe to continuously collect the pulse wave signal, and control the inflation and deflation device of the airbag according to the static pressure application requirement to the measured part and the real-time pressure condition of the airbag to achieve the required inflation and deflation action to meet the inflation and deflation requirements. The measured pulse wave is formed based on the pulse wave signal from the probe, the characteristic variables used to calculate the blood pressure are extracted based on the measured pulse wave, and the blood pressure measurement results are obtained according to the blood pressure calculation model.

[0047] Preferably, the probe is a probe for measuring arterial pulse waves. The host controls the inflation and deflation device of the airbag to increase the static pressure in a step-by-step manner with a certain jump amplitude, forming two or more (including two) static pressure states. In each static pressure state (static pressure value), at least one measured pulse wave (a complete pulse wave) can be obtained (based on the pulse wave signal from the probe). The maximum static pressure value is preferably lower than the static pressure value that can block blood flow, and the static pressure value in the initial stage is greater than zero. The host performs pulse rate normalization and amplitude normalization operations on the pulse wave obtained in one of the static pressure states to form a normalized pulse wave, which is used as a reference pulse wave. The pulse waves obtained in other static pressure states are normalized relative to the reference pulse wave to form relatively normalized normalized pulse waves. The characteristic parameters of the normalized pulse waves are extracted, and the characteristic parameter change rates under adjacent static pressure states used for blood pressure calculation are calculated. Blood pressure data is obtained based on the blood pressure calculation model and the characteristic parameter change rates, which is used as the result of this blood pressure measurement.

[0048] In the above situation, the blood pressure calculation model is preferably a blood pressure calculation model obtained by the following method:

[0049] i) Pulse wave measurement: Continuously measure the arterial pulse wave. During the measurement process, control the static pressure to increase in steps with a certain jump amplitude to form two or more static pressure states. In each static pressure state (static pressure value), measure no less than one pulse wave (a complete pulse wave). The maximum static pressure value is preferably lower than the static pressure value that can block blood flow;

[0050] ii) Pulse wave normalization: The pulse wave measured under one static pressure state (e.g., the maximum static pressure state) is subjected to pulse rate normalization and amplitude normalization to form a normalized pulse wave, which is used as the reference pulse wave. The pulse waves obtained under other static pressure states are normalized relative to the reference pulse wave to form relatively normalized pulse waves.

[0051] For example, a normalized pulse rate and a normalized amplitude are set, the pulse rates of all pulse waves are normalized to the set normalized pulse rate, the amplitude of the pulse wave used as a reference is normalized to the set normalized amplitude, and the amplitude of the pulse wave not used as a reference is normalized according to the normalization coefficient of the pulse wave used as a reference, wherein the pulse wave used as a reference is the pulse wave at the maximum static pressure value;

[0052] iii) Constructing sample data: Extract the characteristic parameters of the normalized pulse wave, measure the corresponding blood pressure (blood pressure of the same subject), calculate the rate of change of the characteristic parameters under adjacent static pressure states, use the characteristic parameter change rate as the model input data, and the blood pressure as the model output data, to form a sample data;

[0053] iv) Constructing a blood pressure calculation model: Selecting a function expression for the blood pressure calculation model and fitting it with a number of sample data to form a blood pressure calculation model.

[0054] The characteristic parameter may be any one or more (including all) of the following characteristic parameters: change in amplitude of the normalized pulse wave under different static pressure states, change in area under the normalized pulse curve, change in duration of the rising edge of the normalized pulse wave, and change in slope of the rising edge of the normalized pulse wave from the starting point to the maximum amplitude point.

[0055] Preferably, the probe is a probe for measuring photoplethysmography. The host controls the inflation and deflation device of the airbag to increase the static pressure in a step-by-step manner with a certain jump amplitude, forming two or more (including two) static pressure states. In each static pressure state (static pressure value), at least one measured pulse wave (a complete pulse wave) can be obtained (based on the pulse wave signal from the probe). The maximum static pressure value is preferably lower than the static pressure value that can block blood flow, and the static pressure value in the initial stage is zero. The host performs pulse rate normalization and amplitude normalization operations on the pulse wave obtained in one of the static pressure states to form a normalized pulse wave, and uses this as a reference pulse wave. The pulse waves obtained in other static pressure states are normalized relative to the reference pulse wave to form relatively normalized normalized pulse waves. The characteristic parameters of the normalized pulse waves are extracted, and the characteristic parameter change rates under adjacent static pressure states used for blood pressure calculation are calculated. Blood pressure data is obtained based on the blood pressure calculation model and the characteristic parameter change rates, which are used as the result of this blood pressure measurement.

[0056] In the above situation, the blood pressure calculation model is preferably a blood pressure calculation model obtained by the following method:

[0057] i) Pulse wave measurement: Continuously perform photoplethysmography pulse wave measurement. During the measurement process, control the static pressure to increase in steps with a certain jump amplitude to form two or more static pressure states. In each static pressure state (static pressure value), measure no less than one pulse wave (complete pulse wave). The maximum static pressure value is preferably lower than the static pressure value that can block blood flow;

[0058] ii) Pulse wave normalization: The pulse wave measured under one static pressure state is normalized by pulse rate and amplitude normalization to form a normalized pulse wave, which is used as the reference pulse wave. The pulse waves obtained under other static pressure states are normalized relative to the reference pulse wave to form relatively normalized normalized pulse waves.

[0059] For example, a normalized pulse rate and a normalized amplitude are set, the pulse rates of all pulse waves are normalized to the set normalized pulse rate, the amplitude of the pulse wave used as a reference is normalized to the set normalized amplitude, and the amplitude of the pulse wave not used as a reference is normalized according to the normalization coefficient of the pulse wave used as a reference, wherein the pulse wave used as a reference is a pulse wave at zero static pressure.

[0060] iii) Constructing sample data: Extract the characteristic parameters of the normalized pulse wave, measure the corresponding blood pressure (blood pressure of the same subject), calculate the rate of change of the characteristic parameters under adjacent static pressure states, use the characteristic parameter change rate as the model input data, and the blood pressure as the model output data, to form a sample data;

[0061] iv) Constructing a blood pressure calculation model: Selecting a function expression for the blood pressure calculation model and fitting it with a number of sample data to form a blood pressure calculation model.

[0062] The characteristic parameter may be any one or more (including all) of the following characteristic parameters: changes in the amplitude of the normalized pulse wave under different static pressure states, changes in the area under the normalized pulse curve, changes in the duration of the rising edge of the normalized pulse wave, and changes in the slope of the rising edge of the normalized pulse wave from the starting point to the maximum amplitude point.

[0063] Preferably, the probe is a probe for measuring arterial pulse waves, and the host controls the inflation and deflation device of the airbag to increase the static pressure uniformly from zero static pressure to the maximum static pressure at a certain speed. The maximum static pressure value is preferably lower than the static pressure value that can block blood flow, and in this process, multiple pulse waves can be formed based on the pulse wave signal from the probe; the host constructs an envelope curve of the pulse wave based on each pulse wave obtained by measurement, performs amplitude normalization operation on the amplitude of the envelope curve obtained at one of the static pressure values, and normalizes the entire envelope curve with the normalization coefficient obtained thereby to form a normalized envelope curve that changes with the static pressure, extracts the characteristic parameters of the normalized envelope curve, and obtains blood pressure data based on the blood pressure calculation model and the characteristic parameters, which is used as the result of this blood pressure measurement.

[0064] In the above situation, the blood pressure calculation model is preferably a blood pressure calculation model obtained by the following method:

[0065] i) Pulse wave measurement: Continuously measure the arterial pulse wave. During the measurement process, control the static pressure to increase uniformly from zero static pressure to maximum static pressure at a certain speed, and measure and obtain multiple pulse waves;

[0066] ii) Constructing a pulse wave envelope curve: constructing a pulse wave envelope curve based on each pulse wave obtained by measurement;

[0067] iii) Envelope curve normalization: performing amplitude normalization operation on the envelope curve to form a normalized envelope curve;

[0068] For example, a normalized amplitude is set, and the envelope curve value (amplitude) corresponding to a certain static pressure (for example, a set maximum static pressure, or, when appropriate, zero static pressure or a static pressure between zero static pressure and the maximum static pressure) on the envelope curve is normalized to the set normalized amplitude, and a corresponding normalization coefficient is recorded. The entire envelope curve is normalized using the normalization coefficient to form a normalized envelope curve that changes with static pressure;

[0069] iv) Constructing sample data: Extract the characteristic parameters of the normalized envelope curve, measure the corresponding blood pressure (blood pressure of the same subject), use the characteristic parameters as model input data, and blood pressure as model output data to form a sample data;

[0070] v) Construct a blood pressure calculation model: Select a function expression for the blood pressure calculation model and use a number of sample data for fitting to form a blood pressure calculation model.

[0071] The characteristic parameter may be any one or more (including all) of the following characteristic parameters: the change in the slope of the line between the reference point and the maximum static pressure point (the point where the static pressure value is the maximum static pressure value), the amplitude ratio of the maximum static pressure point to the reference point, and the static pressure value of the point with an amplitude of 1 / 2 (one half) of the amplitude of the maximum static pressure point, wherein the reference point is located between the zero static pressure point and the maximum static pressure point.

[0072] Preferably, the probe is a probe for measuring photoelectric volumetric pulse waves, and the host controls the inflation and deflation device of the airbag to increase the static pressure uniformly from zero static pressure to the maximum static pressure at a certain speed. The maximum static pressure value is preferably lower than the static pressure value that can block blood flow, and in this process, multiple pulse waves can be formed based on the pulse wave signal from the probe; the host constructs an envelope curve of the pulse wave based on each pulse wave obtained by measurement, performs amplitude normalization operation on the amplitude of the envelope curve obtained at one of the static pressure values, and normalizes the entire envelope curve with the normalization coefficient obtained thereby to form a normalized envelope curve that changes with static pressure, extracts characteristic parameters of the normalized envelope curve, and obtains blood pressure data based on the blood pressure calculation model and the characteristic parameters, which is used as the result of this blood pressure measurement.

[0073] In the above situation, the blood pressure calculation model is preferably a blood pressure calculation model obtained by the following method:

[0074] i) Pulse wave measurement: Continuously perform photoplethysmography measurements. During the measurement process, control the static pressure to increase uniformly from zero static pressure to maximum static pressure at a certain speed, and obtain multiple pulse waves. A pulse wave measurement at zero static pressure may or may not be performed before the static pressure increases uniformly. The pulse wave measurement at zero static pressure and the pulse wave measurement at a uniformly increasing static pressure are performed continuously.

[0075] ii) Constructing a pulse wave envelope curve: constructing a pulse wave envelope curve based on each pulse wave obtained by measurement;

[0076] iii) Envelope curve normalization: performing amplitude normalization operation on the envelope curve to form a normalized envelope curve;

[0077] For example, a normalized amplitude is set, and the envelope curve value (amplitude) corresponding to a certain static pressure (for example, zero static pressure, or, when appropriate, the maximum static pressure or a static pressure between zero static pressure and the maximum static pressure) on the envelope curve is normalized to the set normalized amplitude, and the corresponding normalization coefficient is recorded. The normalization operation is performed on the entire envelope curve using the normalization coefficient to form a normalized envelope curve that changes with static pressure;

[0078] iv) Constructing sample data: Extract the characteristic parameters of the normalized envelope curve, measure the corresponding blood pressure (blood pressure of the same subject), use the characteristic parameters as model input data, and blood pressure as model output data to form a sample data;

[0079] v) Construct a blood pressure calculation model: Select a function expression for the blood pressure calculation model and use a number of sample data for fitting to form a blood pressure calculation model.

[0080] The characteristic parameter can be any one or more (including all) of the following characteristic parameters: the slope of the line between the reference point and the maximum static pressure point (the point where the static pressure value is the maximum static pressure value), the amplitude ratio of the maximum static pressure point to the reference point, and the static pressure value at the point with the maximum slope, and the reference point is located between the zero static pressure point and the maximum static pressure point.

[0081] The beneficial effects of the present invention are: since the blood pressure calculation model is constructed by extracting the characteristic parameters of the pulse wave or the pulse wave envelope curve, it is beneficial to improve measurement accuracy, and only a small number of pulse waves need to be measured to calculate the blood pressure measurement result. The maximum static pressure applied is significantly lower than the static pressure value that can block blood flow. Therefore, while ensuring measurement accuracy and precision, rapid blood pressure measurement can be achieved, and discomfort caused to the person being measured by high static pressure can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] Figure 1 It is a schematic diagram of the structure of the blood pressure measurement device;

[0083] Figure 2 This is a schematic diagram of static pressure and arterial pulse wave involved in blood pressure measurement based on arterial pulse wave in static pressure step-increase mode;

[0084] Figure 3 Schematic diagram of the normalized arterial pulse wave involved in blood pressure measurement based on the arterial pulse wave in the static pressure step-increase mode, wherein the solid line curve is the reference pulse wave P0(t) when the static pressure is SP, and the dotted line curve is the relatively normalized pulse wave P1(t) when the static pressure is SP1;

[0085] Figure 4 Schematic diagram of static pressure and arterial pulse wave involved in blood pressure measurement based on photoplethysmography in static pressure step-increase mode;

[0086] Figure 5 1 is a schematic diagram of the normalized photoplethysmography involved in blood pressure measurement based on photoplethysmography in the static pressure step-increase mode, wherein the dotted line curve is the normalized baseline pulse wave P0(t) when the static pressure is zero, and the solid line curve is the normalized pulse wave P1(t) when the static pressure increases by Δsp;

[0087] Figure 6is a schematic diagram of the photoplethysmography under constant static pressure;

[0088] Figure 7 Schematic diagram of static pressure and arterial pulse wave involved in blood pressure measurement based on arterial pulse wave in static pressure uniform increase mode, where the dotted curve is static pressure and the solid curve is arterial pulse wave;

[0089] Figure 8 Schematic diagram of a normalized envelope curve of an arterial pulse wave as it changes with static pressure in blood pressure measurement based on an arterial pulse wave in a static pressure uniform increase mode;

[0090] Figure 9 Figure 1 is a schematic diagram of the static pressure and arterial pulse wave involved in blood pressure measurement based on photoplethysmography in the static pressure uniform increase mode, where the dotted curve is the static pressure, the solid curve is the arterial pulse wave, and the vertical dotted line indicates the starting time of the static pressure uniform increase;

[0091] Figure 10 1 is a schematic diagram of a normalized envelope curve of photoplethysmography as it changes with static pressure in blood pressure measurement based on photoplethysmography in a static pressure uniform increase mode;

[0092] Figure 11 is a schematic diagram of a blood pressure measuring device according to the present invention;

[0093] Figure 12 is a schematic diagram of another blood pressure measuring device according to the present invention;

[0094] Figure 13 is a schematic diagram of a third blood pressure measurement device according to the present invention;

[0095] Figure 14 is a schematic diagram of a fourth blood pressure measuring device according to the present invention,

[0096] Markings in the figure: 1. External host; 2. Finger cuff; 3. Wrist cuff; 4. Integrated host; 5. Second cuff; 6. Cable connecting the probe and the host. DETAILED DESCRIPTION

[0097] See also Figure 1The present invention can be used as a blood pressure measuring device of the present invention by implementing any of the blood pressure prediction (or measurement) methods disclosed in the present invention on the basis of a conventional sphygmomanometer or other suitable sphygmomanometer with the support of corresponding software. This blood pressure measuring device is mainly composed of a cuff (air bag), a probe (for example, a pressure sensor, or a photoplethysmography probe, etc.), an air pump, a pressure relief valve (or an air release valve), and a control host, wherein the control host is provided with a signal processing and control module and a human-computer interaction interface (for example, a display, input buttons, etc.). The cuff is used to be worn (wrapped around and tied) on the measuring part such as the arm, wrist or fingertip. The air bag is inflated by the air pump, thereby applying pressure (static pressure) to the measuring part, and the corresponding measurement signal is collected by the probe. For example, the pressure sensor can sense the pressure change in the cuff, convert it into an electrical signal, send it to the control host for processing, and generate an arterial pulse wave; the photoplethysmography probe can sense the volume change of the measuring part caused by the pulse, convert it into an electrical signal, send it to the control host for processing, and generate a photoplethysmography (see Figure 6 ). The air release valve is used to control the discharge of gas in the cuff to achieve pressure adjustment (decompression). The air pump and the air release valve can be controlled by the control host (signal processing and control module) to achieve the required static pressure and static pressure change mode. The display screen is used to display the measured blood pressure value and other relevant information. The control host controls and coordinates the work of each component to ensure that the entire measurement process is carried out accurately and stably. The host controls the air pump and the pressure relief valve according to any high-precision, fast and non-invasive blood pressure measurement method disclosed in the present invention to control the static pressure to meet the static pressure requirements of the measurement process, and obtains the required pulse wave (pulse wave information / data) through probe measurement according to the corresponding measurement method. Based on the obtained pulse wave, data processing is performed under the corresponding measurement method to obtain the corresponding processing result, and the required blood pressure calculation model is constructed or the blood pressure detection result is obtained according to the blood pressure calculation model.

[0098] The static pressure can be changed by continuously increasing (or decreasing) it at a constant rate, or by increasing (or decreasing) it at a constant amplitude. During the process of the static pressure changing according to the set method, the pulse wave is continuously measured to obtain the pulse wave under the static pressure change. Based on the measured pulse wave, characteristic parameters related to blood pressure are extracted, and the blood pressure (data of any blood pressure indicator) under the corresponding state is accurately measured (using standard instruments or high-precision instruments). A blood pressure calculation model is constructed. Based on the constructed blood pressure calculation model, in actual blood pressure measurement, the measured pulse wave is obtained according to the same measurement method, and then the measured characteristic parameters are obtained according to the same data processing method. The measured characteristic parameters are substituted into the blood pressure calculation model to calculate the blood pressure measurement result.

[0099] The static pressure value can be controlled by controlling the inflation volume.

[0100] A blood pressure calculation model can be obtained by curve fitting based on a number of sample data. The number of subjects and the selection method can be based on existing technology or relevant regulations.

[0101] The blood pressure (or blood pressure index) to be measured can be any appropriate blood pressure index, such as diastolic pressure, systolic pressure, etc. The static pressure value does not need to reach the level that can block blood flow, and the measurement time is short, which helps to reduce discomfort for the person being measured.

[0102] The arterial pulse wave and the photoplethysmography can be measured using any suitable existing technology.

[0103] When collecting sample data for constructing a blood pressure calculation model, a standard or sufficiently accurate blood pressure measuring instrument may be used to measure the subject's blood pressure, which will serve as the subject's blood pressure data. The subject's blood pressure measurement may be performed simultaneously with the subject's pulse wave measurement to ensure consistency between the model input and output data in the sample data. Where appropriate, other methods (measurement methods and / or measurement times) may be used to obtain sufficiently accurate or standard blood pressure measurements, which will serve as the subject's blood pressure data.

[0104] Example 1. Blood Pressure Measurement Based on Arterial Pulse Waves in Static Pressure Step-Increase Mode

[0105] 1. Constructing a blood pressure calculation model:

[0106] 1) Pulse wave (arterial pulse wave) measurement:

[0107] like Figure 2 As shown, arterial (pressure) pulse waves (pulse waves) are continuously measured. During the measurement process, static pressure is controlled to increase in steps (usually with a constant amplitude) with a certain jump amplitude, forming multiple (for example, two or three) different static pressure states (different static pressure values). At least one complete pulse wave is collected at each static pressure value, and multiple pulse waves can also be collected.

[0108] The maximum static pressure value (the static pressure value at the last static pressure state) SP (or SP0) and the static pressure difference between adjacent static pressure states (equal to the magnitude of each static pressure increase / jump) Δsp can be set based on factors such as accuracy requirements and computational convenience. For example, SP can be 60 mmHg and Δsp can be 20 mmHg. Other manually set parameters involved in the present invention (including various embodiments) can also be set according to the same principles / methods. The starting static pressure value (the static pressure value at the first static pressure state) can be determined based on SP, Δsp, and the selected number of static pressure states (or the number of static pressure jumps).

[0109] When multiple pulse waves are collected at the same static pressure value, the multiple pulse waves can be accumulated and averaged (arithmetic mean) to be used as the pulse wave at the static pressure value.

[0110] 2) Pulse wave normalization:

[0111] Frequency normalization: Normalize the pulse rate of each collected pulse wave to a standard frequency, for example, 75 bpm, to reduce the impact of different heart rates of subjects on model construction and blood pressure measurement results.

[0112] Amplitude Normalization: Normalize the pulse wave amplitude at maximum static pressure to a standard amplitude (fixed value A0) to reduce the impact of varying blood pressure amplitudes across subjects (or individuals undergoing actual blood pressure measurements) on model construction and blood pressure measurement results. The fixed value A0 can be set based on accuracy requirements and computational convenience (for example, roughly equivalent to the average value of the corresponding indicator). The corresponding normalization coefficient can be denoted as k. After frequency normalization, pulse waves at other static pressures are amplitude normalized using the normalization coefficient k (multiplied by k).

[0113] After the above frequency normalization and amplitude normalization, a normalized pulse wave of the corresponding pulse wave is formed. The normalized pulse wave under the maximum static pressure can be used as the reference pulse wave P0(t) for calculation.

[0114] 3) Construct sample data:

[0115] The characteristic parameters of the normalized pulse wave are extracted. These characteristic parameters are related to blood pressure indicators and can be used to construct a blood pressure calculation model (mathematical model).

[0116] Any suitable existing technology or other technology may be used to select and extract feature parameters.

[0117] See also Figure 3 As a preferred embodiment, the characteristic parameters may include: the amplitude of the normalized pulse curve (normalized pulse wave) , the area under the normalized pulse curve (the curve of a single pulse wave) , Normalized pulse wave rising edge time (duration) The slope corresponding to the rising edge of the normalized pulse wave from the starting point to the maximum amplitude point (the slope of the line connecting the starting point of the rising edge to the maximum amplitude point) .

[0118] For the normalized pulse wave (reference pulse wave) P0(t) under the maximum static pressure SP (SP0), calculate the area under the normalized pulse curve (The rising edge starting point can be set as the coordinate origin), normalized pulse wave rising edge time T h_0 , the slope of the normalized pulse wave rising edge from the starting point to the maximum amplitude point The subscript 0 (including T h_0_0) in is represented as the characteristic parameter of the reference pulse wave P0(t).

[0119] For the relative normalized pulse wave under other static pressures, for example, the normalized pulse wave P1(t) under static pressure SP1=(SP-△sp), the normalized pulse wave amplitude A1 and the area under the normalized pulse curve are calculated. , Normalized pulse wave rising edge time T h_1 , the slope of the normalized pulse wave rising edge from the starting point to the maximum amplitude point etc. The subscript 1 in the symbols used to express each characteristic parameter (including T h_1 _1) in represents the characteristic parameters required for the normalized pulse wave P1(t) and other characteristic parameters.

[0120] Without loss of generality, for the static pressure SP i = Normalized pulse wave P under (SP-i△sp) i (t), calculate and obtain the normalized pulse wave amplitude A i (The normalized pulse wave amplitude A0 at maximum static pressure is set during amplitude normalization), the area under the normalized pulse curve , Normalized pulse wave rising edge time T h_i , the slope of the normalized pulse wave rising edge from the starting point to the maximum amplitude point etc., where i=0,1,2,3,......, is the static pressure (static pressure state) number, i=0 corresponds to the maximum static pressure, the larger the static pressure number, the smaller the static pressure value. The subscript i in the symbols used to express each characteristic parameter (including T h_i The _i in the equation represents the normalized pulse wave P i (t) characteristic parameters.

[0121] Calculate the change (rate of change) of pulse wave characteristic parameters under adjacent static pressures (therefore, data under at least two different static pressures are required) as model input (model output data, which can be regarded as independent variables). This includes:

[0122] Amplitude change: ;

[0123] Area change: ;

[0124] Change in pulse wave rising edge time: ;

[0125] Change in the slope of the pulse wave's rising edge: .

[0126] When there are only two static pressure values (measurement data at only two static pressure values), one set of pulse wave characteristic parameter change data at adjacent static pressures can be obtained. When there are only three static pressure values, two sets of characteristic parameter change data at adjacent static pressures can be obtained, and so on. When there are multiple sets of characteristic parameter change data at adjacent static pressures, the average of the characteristic parameter change data can be used as the corresponding characteristic parameter change data for the subject.

[0127] While performing the aforementioned pulse wave measurement, blood pressure can be measured using a precision (standard) blood pressure measuring instrument, with the measured blood pressure (BP value) serving as the model output data (BP data). Where appropriate, precise or standard blood pressure (BP value) measured by other means can also be used as the model output data.

[0128] A sample data is constructed by combining the above corresponding model input data and model output data (model input data and model output data of the same subject).

[0129] 4) Fitting to obtain the blood pressure calculation model:

[0130] The following linear model is used as a mathematical model for calculating blood pressure (BP):

[0131]

[0132] A number of sample data are collected (adopted), and the model coefficients k1, k2, k3, k4 and k5 are fitted by least square fitting or other methods, thereby establishing a blood pressure calculation model.

[0133] According to actual needs, you can also use only 、 、 、 Part of (one or more variables in it), establish only 、 、 、 As can be understood, a calculation model including all the above independent variables can obtain a more accurate blood pressure calculation result.

[0134] In the blood pressure calculation model, only 、 、 、 When a part of the variables is used as an independent variable, there is no need to calculate the variables (data) that are not used as independent variables.

[0135] The number and selection of subjects used to construct the blood pressure calculation model can be based on existing technologies to ensure the accuracy, precision and wide adaptability of the blood pressure calculation model.

[0136] 2. Blood pressure measurement

[0137] Based on the same pulse wave measurement and corresponding data processing method as the aforementioned blood pressure calculation model (the pulse wave measurement and corresponding data processing method implemented on a single subject), the pulse waves when the static pressure is SP1=SP-△sp and SP are measured (if necessary, pulse waves under more static pressure states can also be measured). These pulse waves can be called measured pulse waves. The model independent variables ( 、 、 and or part of it, and / or other independent variables, which may be referred to as measured model independent variables depending on the calculation model used), the measured model independent variable data is brought into the blood pressure calculation model to calculate and obtain the blood pressure data as the result of this blood pressure measurement.

[0138] During pulse wave measurement, at least one complete pulse wave is measured at each static pressure value, though two or more are acceptable, but not necessarily more. Since only a limited number of pulse waves are required to obtain a blood pressure result, measurement time is shortened, efficiency is high, and there is no need to apply a high static pressure value to block blood flow, reducing discomfort for the person being measured.

[0139] Example 2. Blood Pressure Measurement Based on Photoplethysmography in Static Pressure Step-Increase Mode

[0140] 1. Constructing a blood pressure calculation model:

[0141] 1) Pulse wave (photoplethysmography) measurement:

[0142] like Figure 4 As shown, the measurement of photoplethysmography (abbreviated as pulse wave) is continuously implemented. During the measurement process, the static pressure is controlled to increase in a step-by-step manner with a certain jump amplitude (usually a constant amplitude increase) to form multiple (for example, two or three) different (different static pressure values) static pressure states. At least one complete pulse wave is collected at each static pressure value, and multiple pulse waves can also be collected.

[0143] The static pressure value at the starting point (the first static pressure state) is zero. The static pressure difference between adjacent static pressure states (equal to the amplitude of each static pressure increase / jump) △sp can be set based on factors such as accuracy requirements and calculation convenience. For example, △sp can be 20 mmHg.

[0144] When multiple pulse waves are collected at the same static pressure value, the multiple pulse waves can be accumulated and averaged (arithmetic mean) to be used as the pulse wave at the static pressure value.

[0145] 2) Pulse wave normalization:

[0146] Frequency normalization: Normalize the pulse rate of each collected pulse wave to a standard frequency, for example, 75 bpm, to reduce the impact of different heart rates of subjects on model construction and blood pressure measurement results.

[0147] Amplitude Normalization: Normalize the pulse wave amplitude at zero static pressure to a standard amplitude (fixed value A0) to reduce the impact of varying blood pressure amplitudes across subjects (or individuals undergoing actual blood pressure measurements) on model construction and blood pressure measurement results. The fixed value A0 can be set based on accuracy requirements and computational convenience (for example, roughly equivalent to the average value of the corresponding indicator). The corresponding normalization coefficient is denoted as k. After frequency normalization, pulse waves at other static pressures are amplitude normalized using the normalization coefficient k (multiplied by k).

[0148] After the above frequency normalization and amplitude normalization, a normalized pulse wave of the corresponding pulse wave is formed. The normalized pulse wave under zero static pressure is used as the reference pulse wave P0(t) for calculation.

[0149] 3) Construct sample data:

[0150] The characteristic parameters of the normalized pulse wave are extracted. These characteristic parameters are related to blood pressure indicators and can be used to construct a blood pressure calculation model (mathematical model).

[0151] Any suitable existing technology or other technology may be used to select and extract feature parameters.

[0152] See also Figure 5 As a preferred embodiment, the characteristic parameters may include: the amplitude of the normalized pulse curve (normalized pulse wave) , the area under the normalized pulse curve (the curve of a single pulse wave) , Normalized pulse wave rising edge time The slope corresponding to the normalized pulse wave rising edge from the starting point to the maximum amplitude point .

[0153] For the normalized pulse wave (reference pulse wave) P0(t) under zero static pressure, calculate the area under the normalized pulse curve (The rising edge starting point can be set as the coordinate origin), normalized pulse wave rising edge time T h_0 , the slope of the normalized pulse wave rising edge from the starting point to the maximum amplitude point The subscript 0 (including T h_0 _0) in is represented as the characteristic parameter of the reference pulse wave P0(t).

[0154] For normalized pulse waves under other static pressures, for example, normalized pulse wave P1(t) under static pressure SP1=△sp, calculate the normalized pulse wave amplitude A1 and the area under the normalized pulse curve , Normalized pulse wave rising edge time T h_1 , the slope of the normalized pulse wave rising edge from the starting point to the maximum amplitude point etc. The subscript 1 in the symbols used to express each characteristic parameter (including T h_1 The _1) in represents the characteristic parameter of the normalized pulse wave P1(t) relative to the reference pulse wave.

[0155] Without loss of generality, for the static pressure SP i = Normalized pulse wave P under i△sp i (t), calculate and obtain the normalized pulse wave amplitude A i (The normalized pulse wave amplitude A0 at zero static pressure is set during amplitude normalization), the area under the normalized pulse curve , Normalized pulse wave rising edge time T h_i , the slope of the normalized pulse wave rising edge from the starting point to the maximum amplitude point etc., where i=0,1,2,3,......, is the static pressure (static pressure state) number, i=0 corresponds to zero static pressure, the larger the static pressure number, the larger the static pressure value. h_i The _i in the equation represents the normalized pulse wave P i (t) characteristic parameters.

[0156] Calculate the change (rate of change) of pulse wave characteristic parameters under adjacent static pressures (therefore, data under at least two different static pressures are required) as model input (which can be regarded as independent variables). This includes:

[0157] Amplitude change: ;

[0158] Area change: ;

[0159] Change in pulse wave rising edge time: ;

[0160] Change in the slope of the pulse wave's rising edge: .

[0161] When there are only two static pressure values (measurement data at only two static pressure values), one set of pulse wave characteristic parameter change data at adjacent static pressures can be obtained. When there are only three static pressure values, two sets of characteristic parameter change data at adjacent static pressures can be obtained, and so on. When there are multiple sets of characteristic parameter change data at adjacent static pressures, the average of the characteristic parameter change data can be used as the corresponding characteristic parameter change data for the subject.

[0162] While performing the aforementioned pulse wave measurement, blood pressure can be measured using a precision (standard) blood pressure measuring instrument, with the measured blood pressure (BP value) serving as the model output data (BP data). Where appropriate, precise or standard blood pressure (BP value) measured by other means can also be used as the model output data.

[0163] A sample data is constructed by combining the above corresponding model input data and model output data (model input data and model output data of the same subject).

[0164] 4) Fitting to obtain the blood pressure calculation model:

[0165] The following linear model is used as a mathematical model (or blood pressure calculation model) for calculating blood pressure BP:

[0166]

[0167] A number of sample data are collected (adopted), and the model coefficients k1, k2, k3, k4 and k5 are fitted by least square fitting or other methods, thereby establishing a blood pressure calculation model.

[0168] According to actual needs, you can also use only 、 、 、 Part of (one or more variables in it), establish only 、 、 、 As can be understood, a calculation model including all the above independent variables can obtain a more accurate blood pressure calculation result.

[0169] In the blood pressure calculation model, only 、 、 、 When a part of the variables is used as an independent variable, there is no need to calculate the variables (data) that are not used as independent variables.

[0170] The number and selection of subjects used to construct the blood pressure calculation model can be based on existing technologies to ensure the accuracy, precision and wide adaptability of the blood pressure calculation model.

[0171] 2. Blood pressure measurement

[0172] Based on the same pulse wave measurement and corresponding data processing method as the aforementioned blood pressure calculation model (the pulse wave measurement and corresponding data processing method implemented on a single subject), the pulse waves at zero static pressure and static pressure SP1=△sp are measured (if necessary, pulse waves under more static pressure states can also be measured). These pulse waves can be called measured pulse waves. The model independent variables ( 、 、 and or part of it, and / or other independent variables, which may be referred to as measured model independent variables depending on the calculation model used), the measured model independent variable data is brought into the blood pressure calculation model to calculate and obtain the blood pressure data as the result of this blood pressure measurement.

[0173] During pulse wave measurement, at least one complete pulse wave is measured at each static pressure value, though two or more are acceptable, but not necessarily more. Since only a limited number of pulse waves are required to obtain a blood pressure result, measurement time is shortened, efficiency is high, and there is no need to apply a high static pressure value to block blood flow, reducing discomfort for the person being measured.

[0174] Example 3. Blood Pressure Measurement Based on Arterial Pulse Wave in Static Pressure Constant Increase Mode

[0175] 1. Constructing a blood pressure calculation model:

[0176] 1) Pulse wave (arterial pulse wave) measurement:

[0177] like Figure 7 As shown, arterial (pressure) pulse waves (pulse waves for short) are continuously measured. During the measurement process, static pressure is controlled to increase uniformly from a starting static pressure to a maximum static pressure (SPm) at a constant rate (time rate of change), obtaining multiple (for example, 4, 5, 6, 7, or 8) pulse waves. The starting static pressure is zero (zero static pressure), and the ending static pressure can be recorded as SPm (mmHg).

[0178] The static pressure increase rate and maximum static pressure value (SPm) can be set based on factors such as accuracy requirements and computational convenience, so that the desired number (e.g., 4, 5, 6, 7, or 8) of pulse waves can be measured when the static pressure increases from zero (SPm). For example, the SPm can be set to 60 mmHg.

[0179] 2) Constructing the pulse wave envelope curve

[0180] Based on each measured pulse wave (all pulse waves measured during the process of static pressure increasing uniformly from the starting static pressure to the maximum static pressure SPm), an envelope curve of the pulse wave as it changes with static pressure (referred to as a pulse wave envelope curve, or simply envelope curve) is calculated. The pulse wave envelope curve can be a pulse amplitude envelope curve or a pulse area envelope curve. The pulse amplitude envelope curve can be derived using an appropriate calculation method based on the amplitude values of the rising and falling edges of each pulse wave; the pulse area envelope curve can be derived using an appropriate calculation method based on the area of the pulse curve calculated through numerical integration.

[0181] 3) Envelope curve normalization:

[0182] The pulse wave envelope curve is amplitude normalized so that its envelope value when the static pressure is at the maximum static pressure value SPm is Am. Am can be set based on factors such as computational convenience, and the corresponding normalization coefficient can be denoted by k. When the horizontal axis of the coordinate system used for the pulse wave and envelope curve represents static pressure, the envelope curve value is the variable value represented by the vertical axis. For convenience, it can be simply referred to as amplitude and represented by the symbol A.

[0183] 4) Construct sample data:

[0184] The characteristic parameters related to blood pressure of the normalized envelope curve are extracted. These characteristic parameters are related to blood pressure indicators and can be used to construct a blood pressure calculation model (mathematical model) as model input (model output data, which can be regarded as independent variables).

[0185] Any suitable existing technology or other technology may be used to select and extract feature parameters.

[0186] See also Figure 8 As a preferred embodiment, the characteristic parameters may include: the slope change when the static pressure value is SP1 (the amplitude change rate between the point with the maximum static pressure value and the point with the static pressure value of SP1) , the amplitude change ratio when the static pressure value is SP1 (the amplitude ratio of the point with the maximum static pressure value to the point with the static pressure value of SP1) And the envelope curve value (amplitude) is A m Static pressure value at / 2 ,in A1 is the envelope curve value when the static pressure value is SP1. △sp is set according to actual needs, for example, it can be 20 mmHg. When setting SP1 (or △sp), the accuracy of the measurement results and the convenience and accessibility of the calculation should be considered.

[0187] While performing the aforementioned pulse wave measurement, blood pressure can be measured using a precision (standard) blood pressure measuring instrument, with the measured blood pressure (BP value) serving as the model output data (BP data). Where appropriate, precise or standard blood pressure (BP value) measured by other means can also be used as the model output data.

[0188] A sample data is constructed by combining the above corresponding model input data and model output data (model input data and model output data of the same subject).

[0189] 5) Fitting to obtain the blood pressure calculation model:

[0190] The following linear model is used as a mathematical model for calculating blood pressure (BP):

[0191]

[0192] A number of sample data are collected (adopted), and the model coefficients k1, k2, k3 and k4 are fitted by least square fitting or other methods, thereby establishing a blood pressure calculation model.

[0193] According to actual needs, you can also use only △K, R, Part of (one or more variables), establish only △K, R, As can be understood, a calculation model including all the above independent variables can obtain a more accurate blood pressure calculation result.

[0194] In the blood pressure calculation model, only △K, R, When a part of the variables is used as an independent variable, there is no need to calculate the variables (data) that are not used as independent variables.

[0195] The number and selection of subjects used to construct the blood pressure calculation model can be based on existing technologies to ensure the accuracy, precision and wide adaptability of the blood pressure calculation model.

[0196] 2. Blood pressure measurement

[0197] Based on the same pulse wave measurement and corresponding data processing method as the aforementioned blood pressure calculation model (pulse wave measurement and corresponding data processing method implemented on a single subject), the pulse waves of static pressure from the starting static pressure (zero static pressure) to the maximum static pressure value SPm are measured. These pulse waves can be called measured pulse waves. The model independent variables (△K, R and or part of it, and / or other independent variables, which may be referred to as measured model independent variables depending on the calculation model used), the measured model independent variable data is brought into the blood pressure calculation model to calculate and obtain the blood pressure data as the result of this blood pressure measurement.

[0198] Since only a limited number of pulse waves need to be measured to obtain the blood pressure measurement results in actual blood pressure measurement, the measurement time is short and the efficiency is high. There is no need to apply a high static pressure value to block blood flow, which reduces the discomfort of the person being measured.

[0199] Example 4. Blood Pressure Measurement Based on Photoplethysmography in Static Pressure Constant-Rate Increasing Mode

[0200] 1. Constructing a blood pressure calculation model:

[0201] 1) Pulse wave (photoplethysmography) measurement:

[0202] like Figure 9 As shown, photoplethysmography (PPE), or volume wave or pulse wave, is continuously measured. During the measurement, static pressure is controlled to increase uniformly at a certain rate (time rate of change) from a starting static pressure to a maximum static pressure (SPm), obtaining multiple (e.g., 4, 5, 6, 7, or 8) pulse waves. The starting static pressure is zero (zero static pressure), and the ending static pressure can be recorded as SPm (mmHg).

[0203] Before the static pressure increases at a constant rate, a pulse wave measurement at zero static pressure can be performed. This pulse wave measurement at zero static pressure can be performed consecutively with the pulse wave measurement during the constant static pressure increase to enhance the stability and accuracy of the measured data. For calculation purposes, the starting point of the constant static pressure increase can be considered the origin of time (t=0) for ease of calculation.

[0204] 2) Constructing the pulse wave envelope curve

[0205] Based on each measured pulse wave (all pulse waves measured during the process of static pressure increasing uniformly from the starting static pressure to the maximum static pressure SPm), an envelope curve of the pulse wave as it changes with static pressure (referred to as a pulse wave envelope curve, or simply envelope curve) is calculated. The pulse wave envelope curve can be a pulse amplitude envelope curve or a pulse area envelope curve. The pulse amplitude envelope curve can be derived using an appropriate calculation method based on the amplitude values of the rising and falling edges of each pulse wave; the pulse area envelope curve can be derived using an appropriate calculation method based on the area of the pulse curve calculated through numerical integration.

[0206] 3) Envelope curve normalization:

[0207] The pulse wave envelope curve is amplitude normalized so that its envelope value when the static pressure is at the maximum static pressure value SPm is Am. Am can be set based on factors such as computational convenience, and the corresponding normalization coefficient can be denoted by k. When the horizontal axis of the coordinate system used for the pulse wave and envelope curve represents static pressure, the envelope curve value is the variable value represented by the vertical axis. For convenience, it can be simply referred to as amplitude and represented by the symbol A.

[0208] 4) Construct sample data:

[0209] The characteristic parameters related to blood pressure of the normalized envelope curve are extracted. These characteristic parameters are related to blood pressure indicators and can be used to construct a blood pressure calculation model (mathematical model) as model input (model output data, which can be regarded as independent variables).

[0210] Any suitable existing technology or other technology may be used to select and extract feature parameters.

[0211] See also Figure 10 As a preferred embodiment, the characteristic parameters may include: the slope change when the static pressure value is SP1 (the amplitude change rate between the point with the maximum static pressure value and the point with the static pressure value of SP1) , the amplitude change ratio when the static pressure value is SP1 (the amplitude ratio of the point with the maximum static pressure value to the point with the static pressure value of SP1) and the static pressure value SP at the point with the largest slope on the envelope curve km ,in A1 is the envelope curve value when the static pressure value is SP1. △sp is set according to actual needs, for example, it can be 20 mmHg. When setting SP1 (or △sp), the accuracy of the measurement results and the convenience and accessibility of the calculation should be considered.

[0212] While performing the aforementioned pulse wave measurement, blood pressure can be measured using a precision (standard) blood pressure measuring instrument, with the measured blood pressure (BP value) serving as the model output data (BP data). Where appropriate, precise or standard blood pressure (BP value) measured by other means can also be used as the model output data.

[0213] A sample data is constructed by combining the above corresponding model input data and model output data (model input data and model output data of the same subject).

[0214] 5) Fitting to obtain the blood pressure calculation model:

[0215] The following linear model is used as a mathematical model for calculating blood pressure (BP):

[0216]

[0217] A number of sample data are collected (adopted), and the model coefficients k1, k2, k3 and k4 are fitted by least square fitting or other methods, thereby establishing a blood pressure calculation model.

[0218] According to actual needs, you can also use only △K, R, SP km Part of (one or more variables), establish only △K, R, SP km As can be understood, a calculation model including all the above independent variables can obtain a more accurate blood pressure calculation result.

[0219] In the blood pressure calculation model, only △K, R, SP km When a part of the variables is used as an independent variable, there is no need to calculate the variables (data) that are not used as independent variables.

[0220] The number and selection of subjects used to construct the blood pressure calculation model can be based on existing technologies to ensure the accuracy, precision and wide adaptability of the blood pressure calculation model.

[0221] 2. Blood pressure measurement

[0222] Based on the same pulse wave measurement and corresponding data processing method as the aforementioned blood pressure calculation model (pulse wave measurement and corresponding data processing method implemented on a single subject), the pulse waves of static pressure from the starting static pressure (zero static pressure) to the maximum static pressure value SPm are measured. These pulse waves can be called measured pulse waves. The model independent variables (△K, R, SP km or part of it, and / or other independent variables, which may be referred to as measured model independent variables depending on the calculation model used), the measured model independent variable data is brought into the blood pressure calculation model to calculate and obtain the blood pressure data as the result of this blood pressure measurement.

[0223] Since only a limited number of pulse waves need to be measured to obtain the blood pressure measurement results in actual blood pressure measurement, the measurement time is short and the efficiency is high. There is no need to apply a high static pressure value to block blood flow, which reduces the discomfort of the person being measured.

[0224] See also Figure 11-14 , based on the existing arterial pulse wave sphygmomanometer or photoplethysmometer, any of the blood pressure measurement methods disclosed in the present invention can be used to implement continuous non-invasive blood pressure measurement. The blood pressure measurement device can be divided into or set to two measurement modes, one is a precise measurement mode, and the other is a rapid measurement mode. The precise measurement mode uses a relatively long inflation / measurement time and a relatively high maximum static pressure value to obtain relatively more pulse waves or a relatively complete / higher precision envelope curve to obtain characteristic parameters with higher accuracy; the rapid measurement mode does not require a large static pressure value and a long inflation time to achieve blood pressure measurement.

[0225] You can choose to wear it at a suitable measurement site on the body, such as the fingertips, fingertips, wrist, or arm. The cuff and the airbag in the cuff can be selected / designed based on the specific measurement site.

[0226] Figure 11 The illustrated measurement device is used for measuring blood pressure at the finger. It includes an external host 1 and a fingertip cuff 2 equipped with an airbag. The external host performs control, signal processing, and display functions. The fingertip cuff secures the airbag at the measurement site. The airbag is inflated to apply static pressure, and a probe collects arterial pulse waves, enabling accurate and rapid blood pressure measurement. A photoelectric PPG probe (which can be either transmissive or reflective) can be installed on the cuff 2 to detect / collect the photoelectric pulse wave. Alternatively, a combined probe capable of measuring both photoplethysmography and arterial pulse waves (for example, a combined photoplethysmography probe and arterial pulse wave probe, or separate probes) can be installed on the cuff to simultaneously collect both the arterial pulse wave and the photoelectric pulse wave, enabling accurate and rapid blood pressure measurement.

[0227] Figure 12 and Figure 13 The measuring device shown is for measuring blood pressure at the wrist (or arm). Figure 12 The embodiment shown is Figure 11 As shown in the embodiment, an external host 1 is set up. Figure 13 In the illustrated embodiment, the host 4 is integrated with the cuff. This configuration is referred to as an integrated host. The host (external or integrated) performs control, signal processing, and display functions. The wrist cuff 3 is equipped with an airbag and a probe to secure the airbag at the measurement site. The airbag is inflated to apply static pressure, and the probe collects arterial pulse waves, enabling accurate and rapid blood pressure measurement. A photoelectric PPG probe (e.g., a reflective probe) can be provided on the wrist cuff 3 to detect / collect photoelectric pulse waves. Alternatively, a combined probe capable of measuring both photoplethysmography and arterial pulse waves (e.g., a photoplethysmography probe and an arterial pulse wave probe integrated / combined together, or separately provided on the cuff) can be provided on the wrist cuff 3 to simultaneously collect both arterial and photoelectric pulse waves, enabling accurate and rapid blood pressure measurement.

[0228] Figure 14 The measuring device shown is provided with a first cuff and a second cuff, wherein the first cuff is a wrist cuff 3 and the second cuff 6 is a fingertip cuff, which can be worn on the wrist (or arm) and the finger respectively. The specific wearing and measuring methods are respectively the same as Figure 11 The illustrated embodiments and Figure 12 、 Figure 13The embodiment shown is the same. The host used can be an external host 1 or an integrated host 4 provided on the wrist cuff, which is used to implement control, signal processing, and display functions. The output of the probe on the cuff can be connected to the host (e.g., the integrated host 4) via a connecting cable (e.g., a corresponding data cable) 6 between the probe and the host.

[0229] Unless otherwise specified or when one preferred or optional technical means is a further limitation of another technical means, the preferred and optional technical means disclosed in the present invention can be arbitrarily combined to form several different specific implementation methods.

Claims

1. A high-precision, rapid, non-invasive blood pressure measurement method, comprising: continuously measuring pulse waves, applying a varying static pressure to the measurement site during the measurement process, obtaining a measured pulse wave, extracting pulse wave characteristic variables for calculating blood pressure based on the measured pulse wave, and obtaining a blood pressure measurement result using a blood pressure calculation model, wherein the input to the blood pressure calculation model is the pulse wave characteristic variables, and wherein: The blood pressure calculation model is constructed according to the following method: i) Pulse wave measurement: Continuously measure the arterial pulse wave. During the measurement process, control the static pressure to increase in steps with a certain jump amplitude to form two or more static pressure states. At each static pressure state, measure at least one pulse wave; ii) Pulse wave normalization: The pulse wave obtained under one of the static pressure states is subjected to pulse rate normalization and amplitude normalization operations to form a normalized pulse wave, which is used as the reference pulse wave. The pulse waves obtained under other static pressure states are normalized relative to the reference pulse wave to form relatively normalized normalized pulse waves. iii) Constructing sample data: Extract the characteristic parameters of the normalized pulse wave, measure the corresponding blood pressure, calculate the rate of change of the characteristic parameters under adjacent static pressure states, use the characteristic parameter change rate as the model input data, and use the blood pressure as the model output data to form a sample data; iv) Constructing a blood pressure calculation model: Selecting a function expression of the blood pressure calculation model, fitting it with a number of sample data, and forming a blood pressure calculation model.

2. A high-precision, rapid, non-invasive blood pressure measurement method, comprising: continuously measuring pulse waves, applying a varying static pressure to the measurement site during the measurement process, obtaining a measured pulse wave, extracting pulse wave characteristic variables for calculating blood pressure based on the measured pulse wave, and obtaining a blood pressure measurement result using a blood pressure calculation model, wherein the input to the blood pressure calculation model is the pulse wave characteristic variables, and wherein: The blood pressure calculation model is constructed according to the following method: i) Pulse wave measurement: Continuously perform photoplethysmography measurements. During the measurement process, control the static pressure to increase in steps with a certain jump amplitude to form two or more static pressure states. At each static pressure state, measure at least one pulse wave. The static pressure value in the initial stage is zero. ii) Pulse wave normalization: The pulse wave measured under one of the static pressure states is subjected to pulse rate normalization and amplitude normalization to form a normalized pulse wave, which is used as the reference pulse wave. The pulse waves obtained under other static pressure states are normalized relative to the reference pulse wave to form relatively normalized normalized pulse waves. iii) Constructing sample data: Extract the characteristic parameters of the normalized pulse wave, measure the corresponding blood pressure, calculate the rate of change of the characteristic parameters under adjacent static pressure states, use the characteristic parameter change rate as the model input data, and use the blood pressure as the model output data to form a sample data; iv) Constructing a blood pressure calculation model: Selecting a function expression of the blood pressure calculation model, fitting it with a number of sample data, and forming a blood pressure calculation model.

3. A high-precision, rapid, non-invasive blood pressure measurement device, characterized in that include: A cuff, for wearing on the measured part, provided with an air bag for applying static pressure to the measured part, the air bag being provided with an inflation and deflation device, the inflation and deflation device comprising an inflation pump for inflation and an deflation valve for controlling deflation; A probe, used to measure the pulse wave of the measured part; The host is used to control and coordinate the operation of the inflation and deflation device and the probe, enter the blood pressure measurement working mode according to the external input blood pressure measurement instruction, control the probe to continuously collect the pulse wave signal, and implement the control of the inflation and deflation device of the airbag according to the static pressure application requirement to the measured part and the real-time pressure status of the airbag. The measured pulse wave is formed based on the pulse wave signal from the probe, and the pulse wave characteristic variable used for calculating the blood pressure is extracted based on the measured pulse wave. The blood pressure measurement result is calculated according to the blood pressure calculation model. The input of the blood pressure calculation model is the pulse wave characteristic variable. Its characteristics are: The probe is a probe for measuring arterial pulse waves. The host controls the inflation and deflation device of the airbag to increase the static pressure in a step-by-step manner with a certain jump amplitude, forming more than two static pressure states, and at least one measured pulse wave can be obtained in each static pressure state; the host performs pulse rate normalization and amplitude normalization operations on the pulse wave obtained in one of the static pressure states to form a normalized pulse wave, and uses this as a reference pulse wave. The pulse waves obtained in other static pressure states are normalized relative to the reference pulse wave to form a relatively normalized normalized pulse wave, extract characteristic parameters of the normalized pulse wave, calculate the characteristic parameter change rate under adjacent static pressure states used for blood pressure calculation, and obtain blood pressure data based on the blood pressure calculation model and the characteristic parameter change rate calculation as the result of this blood pressure measurement.

4. A high-precision, rapid, non-invasive blood pressure measurement device, characterized in that include: A cuff, for wearing on the measured part, provided with an air bag for applying static pressure to the measured part, the air bag being provided with an inflation and deflation device, the inflation and deflation device comprising an inflation pump for inflation and an deflation valve for controlling deflation; A probe, used to measure the pulse wave of the measured part; The host is used to control and coordinate the operation of the inflation and deflation device and the probe, enter the blood pressure measurement working mode according to the external input blood pressure measurement instruction, control the probe to continuously collect the pulse wave signal, and implement the control of the inflation and deflation device of the airbag according to the static pressure application requirement to the measured part and the real-time pressure status of the airbag. The measured pulse wave is formed based on the pulse wave signal from the probe, and the pulse wave characteristic variable used for calculating the blood pressure is extracted based on the measured pulse wave. The blood pressure measurement result is calculated according to the blood pressure calculation model. The input of the blood pressure calculation model is the pulse wave characteristic variable. Its characteristics are: The probe is a probe for measuring photoplethysmography. The host controls the inflation and deflation device of the airbag to increase the static pressure in a step-by-step manner with a certain jump amplitude, forming more than two static pressure states, and at least one measured pulse wave can be obtained in each static pressure state. The host performs pulse rate normalization and amplitude normalization operations on the pulse wave obtained in one of the static pressure states to form a normalized pulse wave, and uses this as a reference pulse wave. The pulse waves obtained in other static pressure states are normalized relative to the reference pulse wave to form relatively normalized normalized pulse waves, and characteristic parameters of the normalized pulse waves are extracted. The change rate of the characteristic parameters in adjacent static pressure states used for blood pressure calculation is calculated. Blood pressure data is obtained based on the blood pressure calculation model and the characteristic parameter change rate calculation, and used as the result of this blood pressure measurement.

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