Blood pressure measuring method and device, computer equipment and storage medium

Abstract

The invention relates to a blood pressure measuring method and device, computer equipment and a storage medium, and the method comprises the steps that a cuff pressurizing module is started, and an air pump assembly is used for inflating the cuff pressurizing module until the pressure of the cuff pressurizing module exceeds the systolic pressure of a measured person; in the process that the air pump assembly inflates the cuff pressurization module based on the preset inflation rate, cuff pressure data detected by the pressure sensor and PPG data collected by the PPG sensor module are obtained; and performing fusion calculation on the cuff pressure data and the PPG data by using a preset blood pressure calculation model to obtain a blood pressure measurement result. The blood pressure measuring precision and the air inflation rate can be improved, the measuring time is shortened, and then the problem that in the air inflation process, a measured person is pressed by the cuff for a long time, and consequently discomfort is caused can be solved.

Description

[0001] Blood pressure measurement methods, devices, computer equipment, and storage media Technical Field This application relates to the field of medical device technology, and in particular to a blood pressure measurement method, device, computer equipment, and storage medium. Background Technology

[0002] Currently, the most common non-invasive blood pressure measurement methods include the oscillometric method and the photoplethysmography (PPG) method.

[0003] Among these methods, the oscillometric method involves inflating the cuff to a pressure exceeding the systolic pressure of the brachial artery, thereby temporarily blocking blood flow; subsequently, the cuff is slowly deflated, and a pressure sensor collects minute pressure fluctuations within the cuff in real time to determine the blood pressure value. The photoplethysmography (PPG) method uses optical sensors to detect PPG data from locations such as the fingers, and then uses algorithms to estimate the blood pressure value.

[0004] However, the measurement accuracy of the oscilloscope method is greatly affected by the cuff binding state and user movements. Furthermore, excessive pressure rate can affect measurement accuracy. Therefore, in the traditional oscilloscope method, the inflation process takes a long time, causing discomfort to the subject's upper arm due to prolonged cuff compression. While the photoplethysmography method is simple to operate, it is easily affected by factors such as ambient light and skin condition, resulting in lower measurement accuracy. Summary of the Invention

[0005] This application provides a blood pressure measurement method, device, computer equipment, and storage medium, aiming to solve the problem of low measurement accuracy caused by traditional methods using a single oscilloscope or a single photoplethysmography method.

[0006] In a first aspect, embodiments of this application provide a blood pressure measurement method applied to a blood pressure measuring device. The blood pressure measuring device includes a blood pressure measuring device body and a cuff inflation module with a telescopic function. The blood pressure measuring device body is provided with an air pump assembly, a PPG sensor module, a pressure sensor, and a controller. The cuff inflation module can be connected to the air pump assembly and fixed to the arm of the subject. The pressure sensor is connected to the air pump assembly. The PPG sensor module is configured to detect the PPG data of the subject. The controller is electrically connected to the PPG sensor module, the pressure sensor, and the air pump assembly. The controller is used to execute the steps of the blood pressure measurement method, which includes: Activate the cuff pressurization module and use the air pump assembly to inflate the cuff pressurization module until the pressure of the cuff pressurization module exceeds the systolic pressure of the subject. During the process of the air pump assembly inflating the cuff pressurization module based on a preset inflation rate, the cuff pressure data detected by the pressure sensor and the PPG data collected by the PPG sensor module are acquired. The cuff pressure data and PPG data are fused and calculated using a preset blood pressure calculation model to obtain the blood pressure measurement result.

[0007] A further technical solution is that the blood pressure measurement result includes a target systolic blood pressure value and a target diastolic blood pressure value. The step of using a preset blood pressure calculation model to fuse the cuff pressure data and the PPG data to obtain the blood pressure measurement result includes: extracting target pulse wave features from the PPG data and extracting target cuff pressure features from the cuff pressure data. Calculate the first systolic pressure corresponding to the target pulse wave characteristics and the second systolic pressure corresponding to the target cuff pressure characteristics, respectively. Based on the first systolic blood pressure, the second systolic blood pressure, and preset first and second systolic weights, the target systolic blood pressure value is obtained; and Calculate the first diastolic pressure corresponding to the target pulse wave characteristics and the second diastolic pressure corresponding to the target cuff pressure characteristics, respectively. The target diastolic pressure value is obtained based on the first diastolic pressure, the second diastolic pressure, and the preset first diastolic weight and second diastolic weight.

[0008] A further technical solution is that, after determining the target pulse wave characteristics based on the PPG data, the method further includes: The target pulse wave features are subjected to a first filtering process using a high-pass filter to obtain a first PPG feature, wherein the first PPG feature is a PPG feature with baseline drift removed; The first PPG feature is subjected to a second filtering process using a low-pass filter to obtain a second PPG feature, wherein the second PPG feature is a PPG feature with high-frequency noise removed; The PPG data and the second PPG feature are input into a preset adaptive filter; The adaptive filter is used to perform a third filtering process on the PPG data based on the second PPG feature to obtain target PPG data. The second PPG feature is used as the desired data, and the weight coefficients of the adaptive filter are adjusted using the least mean square (LMS) algorithm so that the target PPG data output by the adaptive filter is close to the desired data. The target PPG data is PPG data after removing ambient light interference and motion interference.

[0009] A further technical solution is that the PPG sensor module includes a light source, a photodetector, and an optical shield, wherein the optical shield is disposed between the light source and the photodetector, and the method further includes: Calculate the signal amplitude and signal-to-noise ratio of the PPG data; The luminous intensity of the light source is dynamically adjusted based on the signal amplitude and / or the signal-to-noise ratio.

[0010] A further technical solution is that, after obtaining the blood pressure measurement result, the method further includes: Determine whether the blood pressure measurement result is valid; If the blood pressure measurement result is determined to be valid, then the blood pressure measurement result is displayed; If the blood pressure measurement result is determined to be invalid, the process returns to the step of activating the cuff pressurization module and inflating the cuff pressurization module using the air pump assembly.

[0011] A further technical solution is that determining whether the blood pressure measurement result is valid includes: During the blood pressure measurement process, determine whether the collected cuff pressure data and PPG data meet the preset requirements; If both the cuff pressure data and the PPG data meet the preset requirements, the blood pressure measurement result is deemed valid; and / or Determine whether the blood pressure measurement results meet the preset physiological requirements; If the blood pressure measurement result meets the preset physiological requirements, the blood pressure measurement result is deemed valid.

[0012] A further technical solution is that the blood pressure measurement result includes a target systolic blood pressure value and a target diastolic blood pressure value, and the determination of whether the blood pressure measurement result meets the preset physiological requirements includes: Determine whether the target systolic blood pressure value and the target diastolic blood pressure value are both within a preset pressure range; and whether the difference between the target systolic blood pressure value and the target diastolic blood pressure value is less than a preset difference; If both the target systolic blood pressure and the target diastolic blood pressure are within a preset pressure range, and the difference between the target systolic blood pressure and the target diastolic blood pressure is less than a preset difference, then the blood pressure measurement result is determined to meet the preset physiological requirements.

[0013] Secondly, embodiments of this application also provide a blood pressure measuring device, which includes a unit for performing the above-described method.

[0014] Thirdly, embodiments of this application also provide a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the above-described method.

[0015] Fourthly, embodiments of this application also provide a computer-readable storage medium storing a computer program that, when executed by a processor, can implement the above-described method.

[0016] This application provides a blood pressure measurement method, device, computer equipment, and storage medium. The method includes: activating the cuff inflation module; inflating the cuff inflation module using an air pump assembly until the pressure of the cuff inflation module exceeds the systolic blood pressure of the subject; during the inflation of the cuff inflation module by the air pump assembly at a preset inflation rate, acquiring cuff pressure data detected by a pressure sensor and PPG data collected by a PPG sensor module; and fusing the cuff pressure data and the PPG data using a preset blood pressure calculation model to obtain a blood pressure measurement result.

[0017] This embodiment of the application acquires cuff pressure data detected by the pressure sensor and PPG data collected by the PPG sensor module simultaneously during the inflation of the cuff by the air pump assembly. The blood pressure calculation model then fuses and calculates the cuff pressure data and PPG data. This allows for comprehensive analysis based on both data, improving blood pressure measurement accuracy and overcoming the low accuracy issues associated with traditional methods that rely on either single cuff pressure or single PPG data. Furthermore, the improved blood pressure measurement accuracy allows for a higher inflation rate, enabling the setting of a higher preset inflation rate and shortening the measurement time. This addresses the discomfort caused by prolonged cuff compression during inflation. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0021] Figure 1 A schematic diagram of the assembly structure of a blood pressure measuring device body at one angle, provided in this application; Figure 2 This is a schematic diagram of the assembly structure of a blood pressure measuring device body from another angle, as provided in this application. Figure 3 An exploded structural diagram of the body of a blood pressure measuring device provided in this application; Figure 4 This application provides a schematic diagram of the internal structure connection of a blood pressure measuring device body; Figure 5 This application provides a schematic diagram of the structure of a PPG sensor module in the body of a blood pressure measuring device. Figure 6 This is a schematic flowchart of an embodiment of a blood pressure measurement method provided in this application; Figure 7 This is a schematic diagram of the structure of a computer device provided in an embodiment of this application.

[0022] Explanation of icon numbers: The blood pressure measuring device includes: main body 10, housing 20, acquisition area 21, charging interface 22, cuff connection port 23, air pump assembly 100, air pump 101, air tube 102, air path connection and vent seat 103, vent valve 104, air inlet 105, PPG sensor module 200, light source 201, photodetector 202, pressure sensor 300, and battery 500. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0025] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described feature, integral, step, operation, element and / or component, but do not exclude the presence or addition of one or more other feature, integral, step, operation, element, component and / or collection thereof.

[0026] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0027] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0028] As used in this specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if [described condition or event] is detected" may be interpreted, depending on the context, as "once determined," "in response to determination," "once [described condition or event] is detected," or "in response to detection of [described condition or event]."

[0029] Currently, the most common non-invasive blood pressure measurement methods include the oscillometric method and the photoplethysmography (PPG) method.

[0030] Among these methods, the oscillometric method involves inflating the cuff to a pressure exceeding the systolic pressure of the brachial artery, thereby temporarily blocking blood flow; subsequently, the cuff is slowly deflated, and a pressure sensor collects minute pressure fluctuations within the cuff in real time to determine the blood pressure value. The photoplethysmography (PPG) method uses optical sensors to detect PPG data from locations such as the fingers, and then uses algorithms to estimate the blood pressure value.

[0031] However, the measurement accuracy of the oscilloscope method is greatly affected by the cuff binding state and user movements. Furthermore, excessive pressure rate can affect measurement accuracy. Therefore, in the traditional oscilloscope method, the inflation process takes a long time, causing discomfort to the subject's upper arm due to prolonged cuff compression. While the photoplethysmography method is simple to operate, it is easily affected by factors such as ambient light and skin condition, resulting in lower measurement accuracy.

[0032] To address the aforementioned issues, this application provides a blood pressure measurement method that improves measurement accuracy and inflation rate, shortens measurement time, and thus resolves the problem of discomfort caused by prolonged cuff compression during inflation.

[0033] The blood pressure measurement method provided in this application is applied to blood pressure measurement equipment, see reference. Figures 1-5 The blood pressure measuring device includes a blood pressure measuring device body 10 and a cuff inflation module with telescopic function. The blood pressure measuring device body 10 is provided with an air pump assembly 100, a PPG sensor module 200, a pressure sensor 300, and a controller. The cuff inflation module can be connected to the air pump assembly 100 and fixed at the arm of the subject. The air pump assembly 100 is used to inflate and deflate the cuff inflation module. The pressure sensor 300 is connected to the air pump assembly 100. The PPG sensor module 200 is configured to detect the PPG data of the subject. The controller is electrically connected to the PPG sensor module 200, the pressure sensor 300, and the air pump assembly 100. The controller is used to execute the steps of the blood pressure measuring method provided in the following embodiments.

[0034] In some possible implementations, the PPG sensor module 200 includes a light source 201, a photodetector 202, and an optical shield (not shown in the figure). The optical shield is disposed between the light source 201 and the photodetector 202. The light source 201 emits light of a specific wavelength, and the photodetector 202 receives the reflected light from the surface of the finger skin, thereby obtaining a PPG signal. The optical shield is disposed between the light source 201 and the photodetector 202 to effectively isolate ambient light interference, thereby obtaining a purer and more stable PPG signal.

[0035] See Figures 1-5 The blood pressure measuring device body 10 includes a housing 20, which has an internal cavity. An air pump assembly 100 is disposed in the cavity. The air pump assembly 100 includes an air pump 101, an air tube 102, an air path connector and vent seat 103, and a vent valve 104. The air path connector and vent seat 103 have an air inlet 105. The housing 20 is provided with a cuff connection port 23. The cuff pressurization module is connected to the air inlet 105 through the cuff connection port 23, thus realizing the air path connection with the air pump assembly 100.

[0036] The housing 20 is also provided with a collection area 21. When the user places his finger in the collection area 21, the light source 201 emits light of a specific wavelength, and the photodetector 202 can receive the reflected light from the surface of the finger skin from the collection area 21. In this way, the collection of finger PPG data can be realized.

[0037] Furthermore, the housing 20 is equipped with a charging port 22, and a rechargeable battery 500 is integrated inside the housing 20. Thus, when the battery is low, it can be replenished in real time via the charging port 22 without replacing the battery 500, extending the device's continuous usage time; it also improves ease of use and battery reliability.

[0038] In some possible implementations, the light source 201 can be a single green light, or it can be a combination of green light with other light sources such as red light or infrared light to form a multi-wavelength PPG sensor module 200.

[0039] Since different wavelengths of light have varying depths of reflection in skin tissue and different sensitivities to blood components, by fusing multi-wavelength PPG signals, richer physiological information can be obtained, further improving the accuracy and reliability of blood pressure measurement. At the same time, it can also expand the measurement function of other physiological parameters such as blood oxygen saturation.

[0040] In some embodiments, an adaptive wavelength switching algorithm can be designed to automatically select the most suitable wavelength combination for signal acquisition based on different measurement environments and the skin characteristics of the subject, so as to optimize the measurement effect.

[0041] In some embodiments, since the PPG sensor module 200 does not need to penetrate the finger, it is suitable for people with large differences in finger thickness, such as children and the elderly, and can also be used to measure other parts such as the wrist and earlobe. Furthermore, because the PPG sensor module 200 is smaller in size, it reduces the feeling of restriction when wearing it on the finger, making it suitable for long-term dynamic monitoring.

[0042] In some embodiments, the PPG sensor module 200 can be contact-based, for example, the user can collect PPG data from the finger by pressing the finger on the corresponding acquisition area 21 of the blood pressure measuring device.

[0043] In some embodiments, the PPG sensor module 200 can be non-contact, for example, utilizing optical imaging principles to remotely collect green light reflected from the skin of the finger using a camera or other device, thus achieving non-contact PPG signal acquisition. Furthermore, deep learning algorithms can be combined to process and extract features from the non-contact acquired green PPG signal, establishing a non-contact blood pressure calculation model to ensure measurement accuracy. This avoids direct contact between the PPG sensor module 200 and the skin, improving the hygiene and convenience of the measurement, and making it suitable for special scenarios such as blood pressure measurement in patients with infectious diseases.

[0044] In some embodiments, the cuff compression module is made of a stretchable material that can deform during inflation and deflation, and the inflation and deflation rates can be controllably adjusted during measurement, thereby reducing the pressure on the user and improving wearing comfort and user experience.

[0045] In some embodiments, the reflective PPG sensor module can be designed as a patch module on the back of a watch, paired with a foldable micro cuff (wrapped around the radial artery above the wrist) to achieve portable measurement of "cuff pressure + wrist reflective PPG", suitable for daily health monitoring.

[0046] In some embodiments, a green PPG sensor module and a flexible pressure sensor can be integrated into clothing, particularly at the cuffs and finger areas. The elastic material of the clothing enables the cuff compression function, allowing real-time acquisition of pressure data at the brachial artery and green PPG signals from the fingers when the user wears the health monitoring garment, thus achieving dynamic blood pressure monitoring.

[0047] The blood pressure measurement device provided in this application can be used in hospital remote monitoring systems or home medical terminals.

[0048] One example is the hospital remote monitoring system, which connects blood pressure measuring devices to the hospital's remote monitoring system via a communication module. Medical staff can view real-time blood pressure data for multiple patients at the hospital's monitoring center. The system automatically alarms when abnormal blood pressure is detected, facilitating timely intervention.

[0049] Home healthcare terminal: A dedicated home healthcare terminal device can be developed, integrating this blood pressure measurement device and equipped with a large-screen display and voice interaction functions. This terminal device can connect with other medical devices in the home (such as blood glucose meters, electrocardiographs, etc.) to form a complete home health monitoring system. Measurement data can be automatically uploaded to the cloud for doctors to view and diagnose remotely.

[0050] The blood pressure measuring device provided in this application is compact and portable. Users only need to wear the device and start the measurement program according to the operation prompts to complete the blood pressure test. The operation process is simple, intuitive and easy to use.

[0051] See Figure 6 , Figure 6 This is a flowchart illustrating a first embodiment of a blood pressure measurement method provided in this application. The blood pressure measurement method includes the following steps: Step 110: Activate the cuff pressurization module and use the air pump assembly to inflate the cuff pressurization module until the pressure of the cuff pressurization module exceeds the systolic pressure of the subject.

[0052] Step 120: During the process of the air pump assembly inflating the cuff pressurization module based on a preset inflation rate, acquire the cuff pressure data detected by the pressure sensor and the PPG data collected by the PPG sensor module.

[0053] Step 130: Use a preset blood pressure calculation model to fuse the cuff pressure data and the PPG data to obtain the blood pressure measurement result.

[0054] This embodiment simultaneously acquires cuff pressure data detected by the pressure sensor and PPG data collected by the PPG sensor module during the inflation of the cuff by the air pump assembly. The blood pressure calculation model then fuses and calculates the cuff pressure and PPG data. This allows for comprehensive analysis based on both cuff pressure and PPG data, fully utilizing the advantages of both oscillometric and PPG methods to improve blood pressure measurement accuracy. It addresses the issue of low accuracy caused by traditional methods that rely solely on cuff pressure or PPG data. Furthermore, the improved accuracy allows for a higher inflation rate, enabling the setting of a higher preset inflation rate and shortening the measurement time. This effectively solves the problem of discomfort caused by prolonged cuff compression during inflation.

[0055] In some embodiments, this application can calculate systolic blood pressure, diastolic blood pressure, and pulse rate during the cuff compression completion stage.

[0056] Thus, by increasing the inflation rate, the measurement time can be shortened, thereby solving the problem of discomfort caused by prolonged cuff compression during inflation.

[0057] Referring to a second embodiment of a blood pressure measurement method provided in this application, the blood pressure measurement method includes the following steps: Step 210: Activate the cuff pressurization module and use the air pump assembly to inflate the cuff pressurization module until the pressure of the cuff pressurization module exceeds the systolic pressure of the subject.

[0058] Step 220: During the process of the air pump assembly inflating the cuff pressurization module based on a preset inflation rate, acquire the cuff pressure data detected by the pressure sensor and the PPG data collected by the PPG sensor module.

[0059] Step 230: Use a preset blood pressure calculation model to fuse the cuff pressure data and the PPG data to obtain the blood pressure measurement result.

[0060] In some possible implementations, the blood pressure measurement result includes a target systolic blood pressure value and a target diastolic blood pressure value. Step 230 involves using a preset blood pressure calculation model to fuse the cuff pressure data and the PPG data to obtain the blood pressure measurement result, which may specifically include the following: Step 231: Based on the PPG data, determine the target pulse wave characteristics and extract the target cuff pressure characteristics from the cuff pressure data.

[0061] This can involve processing the PPG signal to obtain a pulse wave, and then extracting feature parameters (such as pulse wave amplitude, pulse wave slope, and pulse wave area) from the pulse wave. In other words, the target pulse wave feature can be the pulse wave amplitude, pulse wave slope, or pulse wave area.

[0062] Step 232: Calculate the first systolic pressure corresponding to the target pulse wave feature and the second systolic pressure corresponding to the target cuff feature, respectively.

[0063] Systolic pressure represents the cuff pressure at which the PPG pulse wave disappears.

[0064] For example, the first systolic blood pressure corresponding to the target pulse wave characteristic can be found in the following formula 1: SBP PPG =k3×P cuff3 +b3, formula 1.

[0065] Among them, P cuff3 SBP refers to the systolic blood pressure corresponding to a pulse wave characteristic that matches the target pulse wave characteristic. PPG This is the first systolic pressure.

[0066] For example, the second contraction pressure corresponding to the target cuff pressure characteristic can be found in the following formula 2: SBP cuff =k1×P cuff1 +b1, formula 2.

[0067] Among them, SBP cuff为 Second systolic pressure, P cuff1 The pressure corresponding to the systolic pressure when the cuff pressure characteristics are met (i.e., the target cuff pressure characteristics).

[0068] Step 233: Based on the first systolic pressure, the second systolic pressure, and the preset first systolic weight and second systolic weight, obtain the target systolic pressure value.

[0069] For example, the target systolic blood pressure value can be found in the following formula 3: SBP=w1×SBP PPG +w2×SBP cuff , Formula 3.

[0070] Where w1 is the weight of the PPG pulse wave in the calculation of systolic blood pressure, i.e., the preset first systolic weight, and w2 is the weight of the cuff pressure characteristics in the calculation of systolic blood pressure, i.e., the preset second systolic weight.

[0071] Step 234: Calculate the first diastolic pressure corresponding to the target pulse wave characteristics and the second diastolic pressure corresponding to the target cuff pressure characteristics, respectively.

[0072] Diastolic pressure refers to the cuff pressure when the PPG pulse wave amplitude drops to 20% of the maximum PPG amplitude.

[0073] For example, the first diastolic pressure corresponding to the target pulse wave characteristic can be found in the following formula 4: DBP PPG =k4×P cuff4 +b4, Formula 4.

[0074] Among them, P cuff4 The diastolic blood pressure corresponding to a pulse wave characteristic that matches the target pulse wave characteristic, DBP. PPG This is the first diastolic pressure.

[0075] For example, the second diastolic pressure corresponding to the target cuff pressure characteristic can be found in the following formula 5: DBP cuff =k2×P cuff2 +b2, Formula 5.

[0076] Among them, P cuff2 The diastolic pressure corresponding to the cuff pressure characteristic meeting the target cuff pressure characteristic (DBP) cuff This is the second diastolic pressure.

[0077] Step 235: Based on the first diastolic pressure, the second diastolic pressure, and the preset first diastolic weight and second diastolic weight, obtain the target diastolic pressure value.

[0078] For example, the target diastolic blood pressure value can be found in the following formula 6: DBP=w3×DBP PPG +w4×DBP cuff , Formula 6.

[0079] Where w3 is the weight of the PPG pulse wave in the calculation of diastolic blood pressure, i.e., the preset first diastolic weight, and w4 is the weight of the cuff pressure characteristics in the calculation of diastolic blood pressure, i.e., the preset second diastolic weight.

[0080] In some embodiments, the cuff pressure signal (P) during the cuff compression process can be continuously acquired. cuff The amplitude-pressure curve (AP curve) is constructed using the pulse wave amplitude signal (A) and the pulse wave amplitude signal (A). Then, the P value is located using the characteristic points of the amplitude-pressure curve. cuff1 and P cuff2 Please refer to the following for details: Step 1: Acquire basic signals and construct AP curves; The cuff is pressurized at a constant rate (2-3 mmHg / s to ensure signal stability), while the pressure sensor collects the real-time cuff pressure and corresponding pulse wave amplitude hundreds of times per second; all collected P... cuff The A data is plotted as a curve to obtain the AP curve.

[0081] Step 2: Locating the key reference point—maximum amplitude (A) max ) and corresponding cuff pressure (P) max ); Specifically, on the AP curve, find the point with the largest amplitude (A). max The cuff pressure at that point is the cuff pressure corresponding to the mean arterial pressure (MAP) (P). max ).

[0082] Step 3: Determine P cuff1 ; P cuff1 Location is determined by an amplitude ratio threshold, following these rules: Define a systolic blood pressure amplitude ratio coefficient (k). SBP =0.4 (determined through clinical calibration), calculate the threshold amplitude A. SBP =k SBP ×A max When the amplitude first reaches A SBP Furthermore, the cuff pressure value corresponding to the first time the slope of the rising edge of the pulse wave exceeds the threshold is P. cuff1 .

[0083] Step 4: Determine P cuff2 ; Location is determined by amplitude ratio threshold, as follows: Define a diastolic blood pressure amplitude ratio coefficient (e.g., k). DBP =0.3 (determined through clinical calibration), calculate the threshold amplitude A. DBP =k DBP ×A max When the amplitude first drops to A DBP The corresponding cuff pressure value is P. cuff2 .

[0084] In addition, b1, b2, b3, and b4 in the above formula are intercept calibration coefficients, and k1, k2, k3, and k4 are intercept calibration coefficients.

[0085] Among them, b1, b2 and k1, k2 are calibration coefficients calculated through comparative experiments between the cuff blood pressure monitor (i.e., pressure sensor + cuff) and the medical standard blood pressure monitor (mercury blood pressure monitor), which are used to correct the deviation of the original measurement value of the cuff blood pressure monitor.

[0086] Specifically, k1 is used for systolic blood pressure calibration: the cuff blood pressure monitor detects the cuff pressure when the pulse wave amplitude reaches a threshold, i.e., P. cuff1 Indirect estimation of systolic blood pressure. P measured by the cuff. cuff The ratio difference between the blood pressure reading and the true systolic blood pressure (SBP) measured by a standard medical sphygmomanometer is corrected by k1, i.e., P cuff1 Multiply by k1. Similarly, k2 is used for diastolic blood pressure calibration to correct P. cuff2 The proportional deviation from the true diastolic blood pressure (DBP).

[0087] b1 is for shrinkage calibration: due to P measured by the cuff. cuff1 There is a fixed difference between P and the true systolic blood pressure (SBP). cuff1 Based on ×k1, b1 (b1 can be positive or negative) is set to offset this fixed offset, so that the result is equal to the true systolic pressure. Similarly, b2 corrects P for diastolic blood pressure calibration. cuff2 A fixed offset from the true diastolic pressure (DBP).

[0088] Specifically, b1, b2 and k1, k2 can be determined in the following ways: 1. Experimental data collection: Select a sufficient number of test subjects; simultaneously measure the blood pressure of each test subject using a cuff sphygmomanometer to be calibrated and a medical standard sphygmomanometer (mercury meter). Among them, the cuff blood pressure monitor records: the characteristic point pressure P corresponding to the systolic blood pressure. cuff1 Diastolic pressure corresponds to characteristic point pressure P cuff2 Medical standard blood pressure monitor records: true systolic blood pressure (SBP) and true diastolic blood pressure (DBP). 2. Linear Regression Coefficient Calculation: Since the cuff characteristic pressure (Pcuff) and true blood pressure (SBP / DBP) have a linear relationship within the physiological range, the data are linearly fitted using the "least squares method," for example, for P... cuff1 By fitting the line to SBP, we obtain the fitted straight line (i.e., the calibration formula): SBP = k1×P cuff1 + b1, at this point k1 (slope) and b1 (intercept) are the calibration coefficients for systolic blood pressure; Similarly, for P cuff2 By fitting the line to DBP, we obtain the straight line DBP = k2×P. cuff2 + b2, where k2 (slope) and b2 (intercept) are the calibration coefficients for diastolic blood pressure.

[0089] In addition, PPG signals are prone to motion interference during acquisition. When motion interference occurs, the movement and shaking of the body will change the contact between the PPG sensor module and the skin, thereby generating additional interference signals. The frequency and amplitude of these interference signals are uncertain.

[0090] Based on this, this application employs a motion artifact elimination algorithm to find the corresponding motion artifact part in the PPG signal according to the identified motion characteristics. An adaptive filtering algorithm is used to dynamically adjust the characteristics of the filter to adapt to changes in motion interference. See the following embodiments for details.

[0091] In addition, b3, b4 and k3, k4 were obtained by comparing the PPG sensor module with the mercury sphygmomanometer. For details, please refer to the relevant content of b1, b2 and k1, k2 above. This application will not repeat them here.

[0092] In some possible implementations, after step 231, i.e., determining the target pulse wave characteristics based on the PPG data, the method may further include: 1) The target pulse wave features are subjected to a first filtering process using a high-pass filter to obtain a first PPG feature, wherein the first PPG feature is a PPG feature with baseline drift removed.

[0093] The high-pass filter can be a first-order IIR Butterworth high-pass filter with a cutoff frequency of 0.5Hz.

[0094] 2) The first PPG feature is subjected to a second filtering process using a low-pass filter to obtain a second PPG feature, wherein the second PPG feature is a PPG feature with high-frequency noise removed.

[0095] The low-pass filter can be a 6th-order IIR Butterworth low-pass filter with a cutoff frequency of 10Hz. Specifically, it can be implemented by cascading three second-order sections (SOS), each of which is second-order, for a total of 6 orders, in order to improve the numerical stability and implementation accuracy of the filter.

[0096] 3) Input the PPG data and the second PPG feature into a preset adaptive filter; 4) The adaptive filter is used to perform a third filtering process on the PPG data based on the second PPG feature to obtain target PPG data. The second PPG feature is used as the desired data, and the weight coefficients of the adaptive filter are adjusted by the least mean square (LMS) algorithm so that the target PPG data output by the adaptive filter is close to the desired data. The target PPG data is PPG data after removing ambient light interference and motion interference.

[0097] Since the second PPG feature obtained after processing by the first-order IIR high-pass filter and the sixth-order IIR low-pass filter is relatively pure, the relatively pure second PPG feature is used as the desired signal d(n). The weight coefficients w(n) of the adaptive filter are updated by the LMS algorithm so that the target PPG data y(n) output by the adaptive filter is as close as possible to the desired signal d(n), i.e. the second PPG feature, thereby achieving adaptive suppression of interference.

[0098] Thus, by performing anti-interference processing on PPG signals (such as green PPG signals), the influence of external environmental factors on the measurement results is reduced, further improving the anti-interference capability of blood pressure measuring equipment.

[0099] In some embodiments, a reflected light feature extraction algorithm can be used. Specifically, feature parameters that can accurately reflect physiological characteristics and have high stability can be extracted from the reflected PPG signal. The reflected PPG features include peak interval, amplitude ratio, rise time, fall time, peak interval area, and exclusion of interference factors from feature extraction.

[0100] In some possible implementations, the stability of the PPG signal can be evaluated by analyzing the amplitude fluctuation range of the PPG signal within a time window; and the monitored PPG signal parameters can be compared with a preset ideal parameter range.

[0101] For example, in some embodiments, the signal amplitude and signal-to-noise ratio of the PPG data are calculated; and the luminous intensity of the light source is dynamically adjusted based on the signal amplitude and / or the signal-to-noise ratio.

[0102] For example, if the signal amplitude is too low or the signal-to-noise ratio is high, it indicates that the luminous intensity is insufficient. In this case, the driving current of the light-emitting element can be increased to improve the luminous intensity. If the signal amplitude is too high and saturation occurs, or the signal-to-noise ratio is low, the driving current of the light-emitting element can be reduced to reduce the luminous intensity.

[0103] In some embodiments, if the signal amplitude is too low and the signal-to-noise ratio is high, the driving current of the light-emitting element can be increased to improve the luminous intensity; if the signal amplitude is too high and the signal-to-noise ratio is low, the driving current of the light-emitting element can be decreased to reduce the luminous intensity.

[0104] In this way, by continuously repeating the above monitoring and feedback adjustment process, the quality of the PPG signal is always kept at a good level, reducing signal fluctuations caused by unsuitable light intensity.

[0105] Referring to a third embodiment of a blood pressure measurement method provided in this application, the blood pressure measurement method includes the following steps: Step 310: Activate the cuff pressurization module and use the air pump assembly to inflate the cuff pressurization module until the pressure of the cuff pressurization module exceeds the systolic pressure of the subject.

[0106] Step 320: During the process of the air pump assembly inflating the cuff pressurization module based on a preset inflation rate, acquire the cuff pressure data detected by the pressure sensor and the PPG data collected by the PPG sensor module.

[0107] Step 330: Use a preset blood pressure calculation model to fuse the cuff pressure data and the PPG data to obtain the blood pressure measurement result.

[0108] Step 340: Determine whether the blood pressure measurement result is valid.

[0109] Step 350: If the blood pressure measurement result is determined to be valid, then the blood pressure measurement result is displayed.

[0110] Step 360: If the blood pressure measurement result is determined to be invalid, return to the step of activating the cuff pressurization module and using the air pump assembly to inflate the cuff pressurization module.

[0111] In some possible implementations, step 340, namely determining whether the blood pressure measurement result is valid, includes: determining whether the cuff pressure data and PPG data collected during the blood pressure measurement process meet preset requirements; if both the cuff pressure data and the PPG data meet the preset requirements, then the blood pressure measurement result is determined to be valid.

[0112] For example, check whether the collection of PPG data and cuff pressure data is stable and complete. If there is signal interruption or abnormally large fluctuations during the collection process, it means that it does not meet the preset requirements and the calculated blood pressure value is unreliable. Therefore, the blood pressure measurement result under such circumstances can be determined to be invalid.

[0113] For example, it can be used to determine whether the waveform of the PPG signal conforms to normal physiological characteristics, whether there is obvious noise or distortion, and thus determine whether the blood pressure measurement result is valid.

[0114] Alternatively, after processing the PPG data using an anti-interference algorithm, it can be determined whether the interference in the processed PPG data has been effectively eliminated. If the processed PPG data still has strong interference, it will affect the accuracy of blood pressure measurement, and the blood pressure measurement result can also be determined to be invalid.

[0115] In some possible implementations, step 340, namely determining whether the blood pressure measurement result is valid, includes: determining whether the blood pressure measurement result meets preset physiological requirements; if the blood pressure measurement result meets preset physiological requirements, then the blood pressure measurement result is determined to be valid.

[0116] In some possible implementations, the blood pressure measurement result includes a target systolic blood pressure value and a target diastolic blood pressure value, and the determination of whether the blood pressure measurement result meets preset physiological requirements includes: 1) Determine whether the target systolic blood pressure value and the target diastolic blood pressure value are both within a preset pressure range; and whether the difference between the target systolic blood pressure value and the target diastolic blood pressure value is less than a preset difference.

[0117] 2) If the target systolic blood pressure and the target diastolic blood pressure are both within the preset pressure range, and the difference between the target systolic blood pressure and the target diastolic blood pressure is less than the preset difference, then the blood pressure measurement result is determined to meet the preset physiological requirements.

[0118] For example, the preset difference can be 18 mmHg, 20 mmHg, etc., and can be set according to the actual situation. This application does not limit it here.

[0119] For example, if the difference between the target systolic blood pressure and the target diastolic blood pressure is less than 18 mmHg, the target systolic blood pressure exceeds the range of 60 mmHg-260 mmHg, and the target diastolic blood pressure exceeds the range of 40 mmHg-220 mmHg, then the blood pressure measurement result is considered not to meet the preset physiological requirements, and the blood pressure measurement result is determined to be invalid.

[0120] Thus, through the above judgment logic, when it is found that the quality of the collected data is poor, the algorithm calculation results are abnormal, or the interference is not effectively eliminated, the blood pressure measurement result is automatically determined to be invalid, thereby triggering a "re-measurement prompt"; otherwise, if all the requirements are met, it is determined to be valid, and subsequent display, storage and other operations are performed.

[0121] In some possible implementations, step 340, namely determining whether the blood pressure measurement result is valid, may involve determining whether the collected cuff pressure data and PPG data meet preset requirements, and whether the blood pressure measurement result meets preset physiological requirements. In this way, the accuracy of blood pressure measurement can be improved.

[0122] Based on the above embodiments, a blood pressure measurement method provided in this application may include the following steps: 1) System initialization; 2) The user wears a cuff with a pressure-applying module; 3) Determine whether to begin measurement; If so, then execute step 4). 4) Activate the cuff pressurization module; 5) Initialize the pressure sensor and PPG sensor module, and use the pressure sensor to collect cuff pressure data and the PPG sensor module to collect PPG data; 6) Preprocess the cuff pressure data and PPG data; This includes noise reduction of cuff pressure data and preliminary filtering of PPG data.

[0123] 7) Perform signal amplification and data synchronization calibration on the preprocessed cuff pressure data and PPG data to obtain calibrated cuff pressure data and PPG data, and cache the calibrated cuff pressure data and PPG data.

[0124] 8) Feature extraction algorithms are used to extract features from the calibrated cuff pressure data and PPG data to obtain target pulse wave features and target cuff pressure features; Specifically, the PPG signal can be sequentially processed by IIR filter, wavelet transform, peak detection, and pulse wave feature parameter extraction to obtain the target pulse wave features; and a smoothing filter can be used to smooth the cuff pressure data, and the target cuff pressure features can be obtained by identifying cuff pressure feature points.

[0125] Among them, wavelet transform processing is used to decompose the signal to obtain different frequency components, and peak detection is used to identify characteristic points during systole and diastole.

[0126] 9) An anti-interference algorithm is used to process the target pulse wave characteristics; The anti-interference algorithms include motion artifact elimination, etc. For details, please refer to the relevant content of the above embodiments, which will not be repeated here.

[0127] 10) Input the target pulse wave characteristics and target cuff pressure characteristics into the preset blood pressure calculation model; 11) The cuff pressure data and the PPG data are fused and calculated using a preset blood pressure calculation model to obtain the blood pressure measurement result.

[0128] 10) Determine whether the blood pressure measurement result is valid; If the result is valid, the blood pressure measurement result will be displayed to the user through the interactive interface; if the result is invalid, the process will return to step 3.

[0129] Corresponding to the above blood pressure measurement methods, this application also provides a blood pressure measuring device. This blood pressure measuring device includes a unit for performing the above blood pressure measurement methods, and can be configured in a desktop computer, tablet computer, laptop computer, or other terminal.

[0130] like Figure 7 As shown in the figure, this application provides a computer device including a processor 111, a communication interface 112, a memory 113, and a communication bus 114, wherein the processor 111, the communication interface 112, and the memory 113 communicate with each other through the communication bus 114. Memory 113 is used to store computer programs; In one embodiment of this application, when the processor 111 executes the program stored in the memory 113, it implements the blood pressure measurement method provided in any of the foregoing method embodiments, including: Activate the cuff pressurization module and use the air pump assembly to inflate the cuff pressurization module until the pressure of the cuff pressurization module exceeds the systolic pressure of the subject. During the process of the air pump assembly inflating the cuff pressurization module based on a preset inflation rate, the cuff pressure data detected by the pressure sensor and the PPG data collected by the PPG sensor module are acquired. The cuff pressure data and PPG data are fused and calculated using a preset blood pressure calculation model to obtain the blood pressure measurement result.

[0131] It will be understood by those skilled in the art that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program may be stored in a storage medium, which is a computer-readable storage medium. The computer program is executed by at least one processor in the computer system to implement the process steps of the embodiments of the above methods.

[0132] Therefore, embodiments of this application also provide a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the blood pressure measurement method provided in any of the foregoing method embodiments, including: Activate the cuff pressurization module and use the air pump assembly to inflate the cuff pressurization module until the pressure of the cuff pressurization module exceeds the systolic pressure of the subject. During the process of the air pump assembly inflating the cuff pressurization module based on a preset inflation rate, the cuff pressure data detected by the pressure sensor and the PPG data collected by the PPG sensor module are acquired. The cuff pressure data and PPG data are fused and calculated using a preset blood pressure calculation model to obtain the blood pressure measurement result.

[0133] The storage medium is a physical, non-transient storage medium, such as a USB flash drive, external hard drive, read-only memory (ROM), magnetic disk, or optical disk, or any other physical storage medium capable of storing program code. The computer-readable storage medium can be non-volatile or volatile.

[0134] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this application.

[0135] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of each unit is merely a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some feature points may be ignored or not executed.

[0136] The steps in the methods of this application embodiment can be adjusted, merged, or deleted according to actual needs. The units in the apparatus of this application embodiment can be merged, divided, or deleted according to actual needs. Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0137] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, a terminal, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application.

[0138] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0139] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Since these modifications and variations fall within the scope of the claims and their equivalents, this application also intends to include these modifications and variations.

[0140] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for measuring blood pressure, characterized in that, An applicable blood pressure measuring device includes a blood pressure measuring device body and a cuff inflation module with a telescopic function. The blood pressure measuring device body is equipped with an air pump assembly, a PPG sensor module, a pressure sensor, and a controller. The cuff inflation module can be connected to the air pump assembly and fixed to the arm of the subject. The pressure sensor is connected to the air pump assembly. The PPG sensor module is configured to detect the subject's PPG data. The controller is electrically connected to the PPG sensor module, the pressure sensor, and the air pump assembly. The controller is used to execute the steps of the blood pressure measurement method, which includes: Activate the cuff pressurization module and use the air pump assembly to inflate the cuff pressurization module until the pressure of the cuff pressurization module exceeds the systolic pressure of the subject. During the process of the air pump assembly inflating the cuff pressurization module based on a preset inflation rate, the cuff pressure data detected by the pressure sensor and the PPG data collected by the PPG sensor module are acquired. The cuff pressure data and PPG data are fused and calculated using a preset blood pressure calculation model to obtain the blood pressure measurement result.

2. The method according to claim 1, characterized in that, The blood pressure measurement result includes a target systolic blood pressure value and a target diastolic blood pressure value. The step of using a preset blood pressure calculation model to fuse the cuff pressure data and the PPG data to obtain the blood pressure measurement result includes: extracting target pulse wave features from the PPG data and extracting target cuff pressure features from the cuff pressure data. Calculate the first systolic pressure corresponding to the target pulse wave characteristics and the second systolic pressure corresponding to the target cuff pressure characteristics, respectively. Based on the first systolic blood pressure, the second systolic blood pressure, and preset first and second systolic weights, the target systolic blood pressure value is obtained; and Calculate the first diastolic pressure corresponding to the target pulse wave characteristics and the second diastolic pressure corresponding to the target cuff pressure characteristics, respectively. The target diastolic pressure value is obtained based on the first diastolic pressure, the second diastolic pressure, and the preset first diastolic weight and second diastolic weight.

3. The method according to claim 1, characterized in that, After determining the target pulse wave characteristics based on the PPG data, the method further includes: The target pulse wave features are subjected to a first filtering process using a high-pass filter to obtain a first PPG feature, wherein the first PPG feature is a PPG feature with baseline drift removed; The first PPG feature is subjected to a second filtering process using a low-pass filter to obtain a second PPG feature, wherein the second PPG feature is a PPG feature with high-frequency noise removed; The PPG data and the second PPG feature are input into a preset adaptive filter; The adaptive filter is used to perform a third filtering process on the PPG data based on the second PPG feature to obtain target PPG data. The second PPG feature is used as the desired data, and the weight coefficients of the adaptive filter are adjusted using the least mean square (LMS) algorithm so that the target PPG data output by the adaptive filter is close to the desired data. The target PPG data is PPG data after removing ambient light interference and motion interference.

4. The method according to claim 1, characterized in that, The PPG sensor module includes a light source, a photodetector, and an optical shield, wherein the optical shield is disposed between the light source and the photodetector, and the method further includes: Calculate the signal amplitude and signal-to-noise ratio of the PPG data; The luminous intensity of the light source is dynamically adjusted based on the signal amplitude and / or the signal-to-noise ratio.

5. The method according to claim 1, characterized in that, After obtaining the blood pressure measurement result, the method further includes: Determine whether the blood pressure measurement result is valid; If the blood pressure measurement result is determined to be valid, then the blood pressure measurement result is displayed; If the blood pressure measurement result is determined to be invalid, the process returns to the step of activating the cuff pressurization module and inflating the cuff pressurization module using the air pump assembly.

6. The method according to claim 5, characterized in that, The determination of whether the blood pressure measurement result is valid includes: During the blood pressure measurement process, determine whether the collected cuff pressure data and PPG data meet the preset requirements; If both the cuff pressure data and the PPG data meet the preset requirements, the blood pressure measurement result is deemed valid; and / or Determine whether the blood pressure measurement results meet the preset physiological requirements; If the blood pressure measurement result meets the preset physiological requirements, the blood pressure measurement result is deemed valid.

7. The method according to claim 6, characterized in that, The blood pressure measurement results include target systolic blood pressure and target diastolic blood pressure. Determining whether the blood pressure measurement results meet preset physiological requirements includes: Determine whether the target systolic blood pressure value and the target diastolic blood pressure value are both within a preset pressure range; and whether the difference between the target systolic blood pressure value and the target diastolic blood pressure value is less than a preset difference; If both the target systolic blood pressure and the target diastolic blood pressure are within a preset pressure range, and the difference between the target systolic blood pressure and the target diastolic blood pressure is less than a preset difference, then the blood pressure measurement result is determined to meet the preset physiological requirements.

8. A blood pressure measuring device, characterized in that, Includes a unit for performing the method as described in any one of claims 1-7.

9. A computer device, characterized in that, The computer device includes a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The storage medium stores a computer program that, when executed by a processor, can implement the method as described in any one of claims 1-7.

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