A method of detecting a non-invasive blood pressure waveform and a blood pressure measuring device

Abstract

The application provides a non-invasive blood pressure waveform detection method and a blood pressure measuring device. A cuff is used to be bound on a subject's limb. An inflation device is communicated with the cuff through an air path to inflate the cuff. A deflation device is communicated with the cuff through an air path to deflate the cuff. A cuff pressure sensor is located on the communication air path between the inflation device and the deflation device and the cuff to detect the gas pressure in the cuff in real time and obtain a pressure oscillation waveform. A controller is electrically connected with the inflation device, the deflation device and the cuff pressure sensor. The controller controls the inflation device, the deflation device and the cuff pressure sensor to perform the inflation and deflation process on the cuff according to the non-invasive blood pressure waveform detection method and generate an envelope curve of blood pressure. The scheme shortens the cycle time of blood pressure measurement.

Description

Technical Field

[0001] This invention relates to the field of medical monitoring technology, and in particular to a non-invasive method for detecting blood pressure waveforms and a blood pressure measuring device. Background Technology

[0002] Blood pressure measurement involves obtaining the maximum arterial pressure exerted during cardiac contraction and the minimum arterial pressure exerted during cardiac diastole, also known as systolic and diastolic pressure. Blood pressure parameters are important physiological parameters that reflect the functional status of the heart, cardiovascular system, and other systems, and are of high reference value for the prevention of various related diseases. Currently, blood pressure measurement methods are mainly divided into two types: invasive blood pressure (IBP) and non-invasive blood pressure (NIBP). IBP is accurate but has certain risks and is not suitable for daily measurement, and is mostly used only in critically ill patients. Non-invasive blood pressure, on the other hand, is non-invasive and its measurement is becoming increasingly accurate, convenient, and practical, so it is now widely used in daily measurement. Currently, NIBP measurement methods primarily focus on the oscillometric principle. This involves inflating and deflating a cuff wrapped around the upper arm to compress the blood vessel, while a pressure sensor collects real-time pulse wave data. The mean blood pressure (MPa), systolic blood pressure (Sp), diastolic blood pressure (Dp), and pulse rate (PR) are calculated based on the patterns of the pulse wave peak curve. The measurement results are then displayed through a human-machine interface. However, the pulse wave signal is weak and easily interfered with, and the measurement inevitably introduces a lot of noise, which negatively impacts the calculation of blood pressure parameters. The control of cuff inflation and deflation, as well as related processing during the inflation and deflation process, directly affects the accuracy, comfort, and applicability of blood pressure measurement.

[0003] Existing NIBP measurements based on the oscilloscope method typically employ step deflation. Step deflation measurement involves first inflating the device, maintaining the pressure, and then gradually deflating it. Each step deflation pressure stage requires a certain duration, resulting in disadvantages such as long measurement time and low measurement comfort. It is also not suitable for people who are sensitive to air pressure. Summary of the Invention

[0004] The purpose of this invention is to provide a non-invasive blood pressure waveform detection method and blood pressure measurement device to solve the problems of long time and poor comfort in the existing stepped deflation blood pressure measurement.

[0005] To address the aforementioned technical problems, this invention provides a non-invasive method for detecting blood pressure waveforms, the method comprising:

[0006] Inflate the cuffs strapped to the subject's limbs using an inflation device;

[0007] The gas pressure inside the cuff is detected in real time by a cuff pressure sensor.

[0008] After the gas pressure inside the cuff reaches the initial inflation pressure, the cuff is gradually deflated using a deflation device. The following steps are performed during the gradual deflation process:

[0009] The gas pressure inside the cuff is controlled to be maintained at the first step pressure, and the first pressure oscillation waveform is obtained in real time using the cuff pressure sensor.

[0010] At least two first pulse waveforms are detected from the first pressure oscillation waveform, the first pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat;

[0011] Based on the at least two first pulse waveforms, the fundamental wave of the first search pressure is determined;

[0012] The cuff is deflated using the aforementioned deflation device;

[0013] During the deflation process, the second pressure oscillation waveform is obtained in real time using the cuff pressure sensor;

[0014] Based on the first search pressure fundamental wave, the first second pulse waveform that matches the first search pressure fundamental wave in the second pressure oscillation waveform is detected in real time;

[0015] Based on the detected first second pulse waveform, at least two third pulse waveforms are detected from the second pressure oscillation waveform, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat;

[0016] The at least two first pulse waveforms and the at least two third pulse waveforms are converted into multiple sets of oscillation amplitude waveforms; and,

[0017] The multiple sets of oscillation amplitude waveforms obtained after multiple deflations are combined to generate the blood pressure envelope curve.

[0018] In one embodiment, the step of detecting, in real time, the first second pulse waveform in the second pressure oscillation waveform that matches the first search pressure fundamental wave, based on the first search pressure fundamental wave, further includes:

[0019] Stop deflation and maintain the current pressure value in the cuff, and perform the step of detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform.

[0020] In one embodiment, the method includes detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform, which comprises:

[0021] After detecting the first second pulse waveform, continue searching for the peaks and troughs in the second pressure oscillation waveform to obtain at least two consecutive pressure pulse waveforms;

[0022] Evaluate the similarity between the first second pulse waveform and the at least two consecutive pressure pulse waveforms; and,

[0023] If the similarity reaches a preset value, then some or all of the at least two consecutive pressure pulse waveforms, together with the first second pulse waveform, are taken as the at least two third pulse waveforms.

[0024] In one embodiment, if the similarity reaches a preset value, the cuff is deflated again using the deflation device.

[0025] In one embodiment, the step of obtaining a first pressure oscillation waveform in real time using the cuff pressure sensor, or obtaining a second pressure oscillation waveform in real time using the cuff pressure sensor, includes:

[0026] The initial pressure oscillation waveform is obtained in real time using the cuff pressure sensor.

[0027] Slide the first moving window to acquire sample segments on the initial pressure oscillation waveform one by one;

[0028] Extract the odd number of waveform data points within the sampled segment, sort them, and obtain the waveform data located in the middle position;

[0029] Replace the last sample point data in the moving window with the waveform data;

[0030] After processing each sampling point on the initial pressure oscillation waveform using the first moving window, a pressure trend signal is obtained; and,

[0031] The first pressure oscillation waveform or the second pressure oscillation waveform is obtained by subtracting the pressure trend signal from the initial pressure oscillation waveform.

[0032] In one embodiment, the step of generating a blood pressure envelope curve from the multiple sets of oscillation amplitude waveforms obtained after multiple deflations includes:

[0033] The multiple sets of oscillation amplitude waveforms obtained after multiple deflations are collected and arranged in chronological order to form a collection with time on the horizontal axis and amplitude on the vertical axis.

[0034] Extract the first waveform data set of several oscillation amplitude waveforms before and after the first moment;

[0035] The amplitude values ​​of the first waveform data set are weighted and averaged to obtain the first curve point, and the first curve point is associated with the first time point.

[0036] Extract the second waveform data set of several oscillation amplitude waveforms before and after the second time point;

[0037] The amplitude values ​​of the second waveform data set are weighted and averaged to obtain the second curve points, and the second curve points are associated with the second time point.

[0038] The first waveform data set and the second waveform data set overlap but are not the same; and,

[0039] Connect the first curve point and the second curve point to generate part or all of the envelope curve of the blood pressure.

[0040] In one embodiment, the process of converting the at least two first pulse waveforms and the at least two third pulse waveforms into multiple sets of oscillation amplitude waveforms includes:

[0041] The at least two first pulse waveforms are combined to obtain the first oscillation pressure amplitude corresponding to the first step pressure;

[0042] The at least two third pulse waveforms are combined to obtain the second oscillation pressure amplitude corresponding to the first step pressure; and,

[0043] The sampling time points corresponding to the first and second oscillation pressure amplitudes are associated and marked to form the multiple sets of oscillation amplitude waveforms.

[0044] In one embodiment, the present invention also provides a non-invasive blood pressure measurement device, the device comprising:

[0045] Cuffs are used to bind the subject's limbs;

[0046] An inflation device, which is connected to the cuff via an air passage, is used to inflate the cuff;

[0047] An air release device is connected to the cuff via an air passage and is used to release air from the cuff.

[0048] A cuff pressure sensor, located on the air path connecting the inflation and deflation devices to the cuff, is used to detect the gas pressure inside the cuff in real time and obtain a pressure oscillation waveform; and,

[0049] A controller, electrically connected to the inflation device, deflation device, and cuff pressure sensor, controls the inflation device, deflation device, and cuff pressure sensor to perform the following process:

[0050] The inflatable device is used to inflate the cuffs strapped to the subject's limbs;

[0051] The gas pressure inside the cuff is detected in real time by the cuff pressure sensor.

[0052] After the gas pressure inside the cuff reaches the initial inflation pressure, the deflation device is used to gradually deflate the cuff. During the gradual deflation process, the following steps are performed:

[0053] The gas pressure inside the cuff is controlled to be maintained at the first step pressure, and the first pressure oscillation waveform is obtained in real time using the cuff pressure sensor.

[0054] At least two first pulse waveforms are detected from the first pressure oscillation waveform, the first pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat;

[0055] Based on the at least two first pulse waveforms, the fundamental wave of the first search pressure is determined;

[0056] The cuff is deflated using the aforementioned deflation device;

[0057] During the deflation process, the second pressure oscillation waveform is obtained in real time using the cuff pressure sensor;

[0058] Based on the first search pressure fundamental wave, the first second pulse waveform that matches the first search pressure fundamental wave in the second pressure oscillation waveform is detected in real time;

[0059] Based on the detected first second pulse waveform, at least two third pulse waveforms are detected from the second pressure oscillation waveform, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat;

[0060] The at least two first pulse waveforms and the at least two third pulse waveforms are converted into multiple sets of oscillation amplitude waveforms;

[0061] The multiple sets of oscillation amplitude waveforms obtained after multiple deflations are combined to generate the blood pressure envelope curve.

[0062] In one embodiment, the device further includes an air container, which is a cavity structure containing multiple air holes. The multiple air holes are respectively connected to the cuff, the inflation device, the deflation device, and the cuff pressure sensor through air tubes.

[0063] In one embodiment, the method includes detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform, which comprises:

[0064] After detecting the first second pulse waveform, continue searching for the peaks and troughs in the second pressure oscillation waveform to obtain at least two consecutive pressure pulse waveforms;

[0065] Evaluate the similarity between the first second pulse waveform and the at least two consecutive pressure pulse waveforms; and,

[0066] If the similarity reaches a preset value, then some or all of the at least two consecutive pressure pulse waveforms, together with the first second pulse waveform, are taken as the at least two third pulse waveforms.

[0067] And / or, the step of obtaining a first pressure oscillation waveform in real time using the cuff pressure sensor, or obtaining a second pressure oscillation waveform in real time using the cuff pressure sensor, includes:

[0068] The initial pressure oscillation waveform is obtained in real time using the cuff pressure sensor.

[0069] Slide the first moving window to acquire sample segments on the initial pressure oscillation waveform one by one;

[0070] Extract the odd number of waveform data points within the sampled segment, sort them, and obtain the waveform data located in the middle position;

[0071] Replace the last sample point data in the moving window with the waveform data;

[0072] After processing each sampling point on the initial pressure oscillation waveform using the first moving window, a pressure trend signal is obtained; and,

[0073] The first pressure oscillation waveform or the second pressure oscillation waveform is obtained by subtracting the pressure trend signal from the initial pressure oscillation waveform.

[0074] And / or, the step of generating a blood pressure envelope curve from the multiple sets of oscillation amplitude waveforms obtained after multiple deflations of the set includes:

[0075] The multiple sets of oscillation amplitude waveforms obtained after multiple deflations are collected and arranged in chronological order to form a collection with time on the horizontal axis and amplitude on the vertical axis.

[0076] Extract the first waveform data set of several oscillation amplitude waveforms before and after the first moment;

[0077] The amplitude values ​​of the first waveform data set are weighted and averaged to obtain the first curve point, and the first curve point is associated with the first time point.

[0078] Extract the second waveform data set of several oscillation amplitude waveforms before and after the second time point;

[0079] The amplitude values ​​of the second waveform data set are weighted and averaged to obtain the second curve points, and the second curve points are associated with the second time point.

[0080] The first waveform data set and the second waveform data set overlap but are not the same; and,

[0081] Connect the first curve point and the second curve point to generate part or all of the envelope curve of the blood pressure.

[0082] The non-invasive blood pressure waveform detection method provided by this invention achieves rapid detection by detecting pulse waveforms under adjacent step pressures, without having to wait for the deflation step pressure to stabilize before pulse wave detection can begin. This saves the time spent waiting for pressure stabilization before sampling during each deflation process. In addition, it avoids abnormal waveform interference caused by deflation, thus connecting the last pressure wave of the previous pressure plateau with the first pressure wave of the next pressure plateau, thereby achieving seamless and continuous connection of pressure signals, shortening the blood pressure measurement cycle time, shortening the pressure holding time of step deflation, and improving comfort. Attached Figure Description

[0083] Figure 1 This is a schematic diagram of the blood pressure measuring device in this invention.

[0084] Figure 2 This is a schematic flowchart of the non-invasive blood pressure waveform detection method of the present invention.

[0085] Figure 3 This is a schematic diagram of the process waveforms of the detection method of the present invention, wherein (a) is the initial pressure oscillation waveform; (b) the oscillation waveform after processing; (c) the amplitude change waveform; and (d) the blood pressure envelope curve. Detailed Implementation

[0086] Typical embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations herein are for illustrative purposes only and not intended to limit the present invention.

[0087] To further illustrate the principles and structure of the present invention, preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0088] This invention is based on an improvement of a non-invasive blood pressure measurement device, and in particular on an improvement of the non-invasive blood pressure waveform detection method in the non-invasive blood pressure measurement device.

[0089] like Figure 1 As shown, a non-invasive blood pressure measurement device includes: a cuff 310, a controller 320, an inflation device 330, a deflation device 340, a cuff pressure sensor 350, and a display 360;

[0090] The cuff 310 is used to bind the subject's limbs;

[0091] The inflation device 330 is connected to the cuff 310 through an air passage and is used to inflate the cuff 310.

[0092] The venting device 340 is connected to the cuff 310 through an air passage and is used to vent the cuff 310.

[0093] The cuff pressure sensor 350 is located on the air path connecting the inflation device 330 and the deflation device 340 with the cuff 310, and is used to detect the gas pressure in the cuff in real time and obtain the pressure oscillation waveform.

[0094] The controller 320 is electrically connected to the inflation device 330, deflation device 340, and cuff pressure sensor 350. The controller 320 controls the inflation device 330, deflation device 340, and cuff pressure sensor 350 to perform inflation and deflation processes on the cuff 310 according to the non-invasive blood pressure waveform detection method proposed in this invention, and generates a blood pressure envelope curve (e.g., ...). Figure 3 As shown in Figure 800, blood pressure measurements are obtained based on the envelope curve and displayed on the display 360. The mean blood pressure, diastolic pressure, and systolic pressure values ​​can be calculated based on the peak value, rising edge, and falling edge of the blood pressure envelope curve 800. The deflation device 340 is connected to the outside. When the deflation device 340 is opened, it connects to the atmosphere to deflate the cuff. When the deflation device 340 is closed, it disconnects from the atmosphere, preventing the cuff from deflating.

[0095] like Figure 1As shown, in some embodiments of the present invention, in order to ensure the stability of the air pressure in the connected air path and facilitate the collection of more accurate information, especially to capture the slight pressure changes in the cuff caused by heartbeat, an air container 380 can be added to the above-mentioned device. The air container 380 is a cavity structure containing multiple air holes. The multiple air holes are respectively connected to the cuff 310, the inflation device 330, the deflation device 340, and the cuff pressure sensor 350 through air tubes. That is to say, the cuff 310, the inflation device 330, the deflation device 340, and the cuff pressure sensor 350 are connected to each other through the air container 380.

[0096] like Figure 1 As shown, in some embodiments of the present invention, the inflation device 330 includes a pump, which is connected to the cuff 310 via an air path; the pump is electrically connected to the controller 320; the controller 320 sends a control signal to the pump to start or stop the pump. Based on this design, in some embodiments of the present invention, multiple air holes on the air container 380 are respectively connected to the cuff 310, the pump, and the cuff pressure sensor 350 via air pipes. When the pump is started and the deflation device is closed, it is used to inflate the cuff; when the pump is closed and the deflation device is open, it is used to deflate the cuff.

[0097] like Figure 1 As shown, in some embodiments of the present invention, the deflation device 340 includes a deflation valve, which is connected to the cuff 310 via an air path; the deflation valve is electrically connected to the controller 320; the controller 320 sends start and stop signals to the deflation valve to inflate and deflate the cuff 310 according to the non-invasive blood pressure waveform detection method proposed in this invention. When the inflation device (i.e., pump) is started and the deflation device is closed, it is used to inflate the cuff; when the inflation device (i.e., pump) is closed and the deflation device is opened, it is used to deflate the cuff. Based on this design, in some embodiments of the present invention, multiple air holes on the air container 380 are respectively connected to the cuff 310, the deflation valve, and the cuff pressure sensor 350 via air pipes.

[0098] like Figure 1As shown, in some embodiments of the present invention, the cuff pressure sensor 350 may include one or more pressure sensors. For example, the cuff pressure sensor 350 includes a cuff inflation pressure sensor 351 and a cuff deflation pressure sensor 352; the cuff inflation pressure sensor 351 and the cuff deflation pressure sensor 352 are electrically connected to the controller 320 and are used to transmit pressure signals (such as pressure values ​​and / or pressure oscillation waveforms) collected in the air path to the controller 320. The cuff inflation pressure sensor 351 is located in the air path connecting the inflation device 330 and the cuff 310. The cuff deflation pressure sensor 352 is located in the air path connecting the deflation device 340 and the cuff 310. Using separate air pressure sensors allows for more accurate and timely collection of cuff pressure values ​​and / or pressure oscillation waveforms. Based on this design, in some embodiments of the present invention, multiple air holes on the air container 380 are respectively connected to the cuff inflation pressure sensor 351 and the cuff deflation pressure sensor 352 through air tubes. For example, such as Figure 1 As shown, in some embodiments of the present invention, multiple air holes on the air container 380 are respectively connected to the cuff 310, the deflation valve, the pump, the cuff inflation pressure sensor 351, and the cuff deflation pressure sensor 352 via air pipes. In the above embodiments, the deflation device (such as the deflation valve) needs to be connected to atmospheric pressure to realize the inflation and deflation process. When the deflation valve is opened, the aforementioned air path is connected to atmospheric pressure to realize deflation; conversely, during inflation, the deflation valve is closed.

[0099] based on Figure 1 The blood pressure measuring device shown is, for example Figure 2 As shown, the present invention provides a method for detecting non-invasive blood pressure waveforms on the aforementioned non-invasive blood pressure measurement device. It mainly improves the speed of deflation measurement and increases the rate of step deflation blood pressure measurement. The method includes step 100: the controller 320 inflates the cuff 310 using the inflation device 330; and step 200: the controller 320 deflates the cuff 310 using the deflation device 340 and obtains the blood pressure envelope curve 800.

[0100] In step 100, during the process of inflating the cuff 310 using the inflation device 330, the controller 320 performs the following steps:

[0101] Step 110: Inflate the cuff 310 bound to the subject's limb using the inflation device 330;

[0102] Step 120: The gas pressure inside the cuff 310 is detected in real time by the cuff pressure sensor 350.

[0103] Step 130: Determine whether the gas pressure inside the cuff 310 has reached the initial inflation pressure; during step 200, when the controller 320 deflates the cuff 310 using the deflation device 340 and obtains the blood pressure envelope curve, after the gas pressure inside the cuff 310 reaches the initial inflation pressure, the controller 320 begins to deflate the cuff 310 sequentially using the deflation device 340. During the sequential deflation process, the controller 320 executes steps 210-290. If the gas pressure inside the cuff 310 has not yet reached the initial inflation pressure, the process returns to step 110: inflating the cuff 310 bound to the subject's limb using the inflation device 330.

[0104] like Figure 2 and Figure 3 As shown, during the successive venting process, the controller 320 executes the following steps 210-290, as detailed below:

[0105] Step 210: Control the gas pressure in the cuff 310 to maintain the first step pressure 410, and use the cuff pressure sensor 350 to obtain the first pressure oscillation waveform 610 in real time;

[0106] Step 220: Detect at least two first pulse waveforms from the first pressure oscillation waveform 610, the first pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat;

[0107] Step 230: Based on the at least two first pulse waveforms, determine the first search pressure fundamental wave 620;

[0108] Step 240: Depress the cuff 310 using the deflator 340;

[0109] Step 250: During the deflation process, the second pressure oscillation waveform 640 is obtained in real time using the cuff pressure sensor 350;

[0110] Step 260: Based on the first search pressure fundamental wave 620, detect in real time the first second pulse waveform 630 in the second pressure oscillation waveform 640 that matches the first search pressure fundamental wave 620;

[0111] Step 270: Based on the detected first second pulse waveform 630, at least two third pulse waveforms are detected from the second pressure oscillation waveform 640, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat;

[0112] Step 280: Convert the at least two first pulse waveforms 610 and the at least two third pulse waveforms 640 into multiple sets of oscillation amplitude waveforms 700;

[0113] Step 290: Combine the multiple sets of oscillation amplitude waveforms 700 obtained after multiple deflations to generate the blood pressure envelope curve 800.

[0114] In some embodiments of the present invention, during the above steps 210-290, the controller 320 may use the cuff deflation pressure sensor 352 to obtain the first pressure oscillation waveform 510 and the second pressure oscillation waveform 520 in real time.

[0115] The non-invasive blood pressure waveform detection method provided by this invention achieves rapid detection by detecting pulse waveforms under adjacent pressure steps, eliminating the need to wait for the pressure steps to stabilize before pulse wave detection can begin. This saves time waiting for pressure stabilization during each deflation process. Furthermore, it avoids interference from abnormal waveforms introduced by deflation, thus seamlessly connecting the last pressure wave of the preceding pressure plateau with the first pressure wave of the following pressure plateau, shortening the blood pressure measurement cycle time. This invention also shortens the pressure holding time during step deflation, improving comfort.

[0116] In some embodiments of the present invention, such as Figure 3 As shown, in step 260 above, based on the first search pressure fundamental wave, the controller 320 detects in real time the first second pulse waveform in the second pressure oscillation waveform that matches the first search pressure fundamental wave, and then further includes:

[0117] Stop deflation and maintain the current pressure value in the cuff, which is the second-step pressure 420. Then, perform step 270: based on the detected first second pulse waveform, detect at least two third pulse waveforms from the second pressure oscillation waveform.

[0118] Of course, in some embodiments of the present invention, the process of detecting the first second pulse waveform 630 that matches the first search pressure fundamental wave 620 in the second pressure oscillation waveform 640 in real time based on the first search pressure fundamental wave 620 in step 260 can be implemented in the following way:

[0119] Search for the peaks and troughs in the second pressure oscillation waveform 640 one by one to obtain the pressure pulse waveform;

[0120] Determine whether the searched pressure pulse waveform is similar to the first searched pressure fundamental wave 620. If it is similar, then the currently searched pressure pulse waveform is regarded as the first second pulse waveform 630. If it is not similar, then repeat the step of searching for the peaks and troughs in the second pressure oscillation waveform 640 one by one to obtain the pressure pulse waveform, until the step of determining whether the searched pressure pulse waveform is similar to the first searched pressure fundamental wave 620.

[0121] Of course, if the controller 320 can continuously obtain multiple similar pulse waveforms after detecting the first second pulse waveform in the second pressure oscillation waveform that matches the fundamental wave of the first search pressure in real time, then the process of stopping the deflation and maintaining the current pressure value in the cuff does not need to be performed. In other words, the deflation can be achieved again without maintaining the second step pressure 420 for too long during the detection process. Alternatively, multiple similar pressure pulse waveforms can be obtained in an extremely short time after searching for the first second pulse waveform, so the second step pressure 420 does not need to be maintained, and continuous deflation can be achieved. This further shortens the deflation detection time.

[0122] In some embodiments of the present invention, such as Figure 3 As shown, the process of detecting at least two first pulse waveforms 610 from the first pressure oscillation waveform 510 in the aforementioned step 220 is as follows:

[0123] Search for the peaks and troughs in the first pressure oscillation waveform 610 one by one to obtain at least three pressure pulse waveforms;

[0124] If the amplitude and frequency of two adjacent pressure pulse waveforms among the at least three pressure pulse waveforms searched are similar, and they are similar, it indicates that at least two first pulse waveforms have been detected, and at least two of the at least three pressure pulse waveforms searched are selected as the at least two first pulse waveforms; otherwise, if they are not similar, the step of searching for the peaks and troughs in the first pressure oscillation waveform 610 one by one to obtain at least three pressure pulse waveforms is repeated until the step of determining whether the amplitude and frequency of two adjacent pressure pulse waveforms among the at least three pressure pulse waveforms searched are similar is performed.

[0125] In some embodiments of the present invention, such as Figure 3 As shown, step 230 above: Based on the at least two first pulse waveforms, the first search pressure fundamental wave 620 is determined, which is achieved through the following process:

[0126] The at least two first pulse waveforms are combined to determine the fundamental wave 620 of the first search pressure. The merging method can be averaging; or...

[0127] Select the one with the most recent time from the at least two first pulse waveforms as the first search pressure fundamental wave 620.

[0128] This method is simple and reliable, and can quickly filter out interference signals or jitter interference in pressure oscillation waveforms.

[0129] In some embodiments of the present invention, such as Figure 3 As shown, in the method, step 270, which involves detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform, includes:

[0130] After detecting the first second pulse waveform 630, continue to search for the peaks and troughs in the second pressure oscillation waveform 610 to obtain at least two consecutive pressure pulse waveforms;

[0131] Evaluate the similarity between the first second pulse waveform 630 and the at least two consecutive pressure pulse waveforms;

[0132] If the similarity reaches a preset value, then some or all of the at least two consecutive pressure pulse waveforms, together with the first second pulse waveform 630, are taken as the at least two third pulse waveforms.

[0133] The similarity between the first second pulse waveform 630 and the at least two consecutive pressure pulse waveforms can be evaluated by comparing the similarity of various features such as waveform amplitude, frequency of adjacent waveforms, and waveform shape. The similarity comparison can be approximately the same or completely identical.

[0134] Based on the first second pulse waveform 630, pressure pulse waveforms on the same stepped pressure platform can be quickly identified by waveform similarity judgment.

[0135] In some embodiments of the present invention, such as Figure 3 As shown, to further improve measurement speed, in step 270, if the similarity between the first second pulse waveform 620 and the at least two consecutive pressure pulse waveforms reaches a preset value, the cuff 310 is immediately deflated again using the deflation device 340. Therefore, by comparing the similarity with adjacent waveforms (waveforms below the previous pressure plateau), a rapid deflation strategy can be implemented, eliminating the need to continuously wait for the pressure plateau and calculate the DC component, thus shortening the measurement time.

[0136] In some embodiments of the present invention, such as Figure 3As shown, in the method, the step 210 above, which involves obtaining the first pressure oscillation waveform in real time using the cuff pressure sensor, or the step 250 above, which involves obtaining the second pressure oscillation waveform in real time using the cuff pressure sensor, includes the following process:

[0137] The initial pressure oscillation waveform is obtained in real time using the cuff pressure sensor 350. For example, in step 210, the first pressure oscillation waveform 510 is obtained in real time using the cuff pressure sensor 350; or, in step 250, the second pressure oscillation waveform 520 is obtained in real time using the cuff pressure sensor 350.

[0138] Slide the first moving window 910 to acquire the sample segments on the initial pressure oscillation waveform (510, 520) one by one;

[0139] Extract the odd number of waveform data points within the sampled segment, sort them, and obtain the waveform data located in the middle position;

[0140] Replace the last sample point data in the moving window with the waveform data;

[0141] After processing each sampling point on the initial pressure oscillation waveform (510, 520) using the first moving window 910, a pressure trend signal is obtained;

[0142] The pressure trend signal is subtracted from the initial pressure oscillation waveform (510, 520) to obtain the first pressure oscillation waveform 610 or the second pressure oscillation waveform 640.

[0143] By processing the initial pressure oscillation waveforms (510, 520) in this way, the influence of blood echo waves can be eliminated, and the effective signal of the cardiac ejection segment can be extracted. Furthermore, the large drop signal during the deflation phase between pressure platforms can be quickly suppressed. This allows the last pressure wave of the previous platform to be connected with the first pressure wave of the subsequent platform, thus achieving a seamless and continuous connection of pressure signals and shortening the platform cycle.

[0144] In some embodiments of the present invention, such as Figure 3 As shown, in the method, the process of converting the at least two first pulse waveforms and the at least two third pulse waveforms into multiple sets of oscillation amplitude waveforms in step 280 includes:

[0145] The at least two first pulse waveforms detected on the first pressure oscillation waveform 610 are combined to obtain the first oscillation pressure amplitude 710 corresponding to the first step pressure 410.

[0146] The at least two third pulse waveforms detected on the second pressure oscillation waveform 640 are combined to obtain the second oscillation pressure amplitude 720 corresponding to the second stepped pressure 420; and,

[0147] By associating and marking the sampling time points corresponding to the first oscillation pressure amplitude 710 and the second oscillation pressure amplitude 720 respectively, the multiple sets of oscillation amplitude waveforms 700 are formed, as shown below. Figure 3 (c) in the middle.

[0148] In some embodiments of the present invention, such as Figure 3 As shown, in the method, the step of generating the blood pressure envelope curve 800 by collecting the multiple sets of oscillation amplitude waveforms 700 obtained after multiple deflations in step 290 includes:

[0149] The multiple sets of oscillation amplitude waveforms 700 obtained after multiple deflations are collected and arranged in chronological order to form a collection with time on the horizontal axis and amplitude on the vertical axis. Figure 3 (d) in the middle;

[0150] Extract the first waveform data set of several oscillation amplitude waveforms before and after the first moment A;

[0151] The amplitude values ​​of the first waveform data set are weighted and averaged to obtain the first curve point E, and the first curve point E is associated with the first time point A.

[0152] Extract the second waveform data set of several oscillation amplitude waveforms before and after the second time point B;

[0153] A weighted average of the amplitude values ​​in the second waveform data set is calculated to obtain the second curve point F, and the second curve point F is associated with the second time point B; and,

[0154] Connecting the first curve point E and the second curve point F generates part or all of the envelope curve 800 of the blood pressure. The first waveform data set and the second waveform data set overlap but are not identical. The advantage of the above curve fitting method is that it can retain the trend information of the data while eliminating noise. In some embodiments of the present invention, the number of the aforementioned extracted oscillation amplitude waveforms is at least greater than 5. Using a weighted average of five or more adjacent data points to calculate the smoothed data points can retain the trend information of the data while eliminating noise and reducing the amount of data computation.

[0155] In the similarity evaluation or matching judgment mentioned in the method of this invention, the similarity judgment can be made by comparing the waveform's amplitude, amplitude variation, frequency, waveform shape, etc., with a threshold or preset waveform. The similarity judgment can be identical or approximately identical.

[0156] As can be seen from the above technical solution, the advantages and positive effects of this invention are as follows: Rapid detection is achieved by detecting pulse waveforms under adjacent step pressures, eliminating the need to wait for the pressure to stabilize during deflation before pulse wave detection can begin. This saves the time spent waiting for pressure stabilization before sampling during each deflation process. Furthermore, it avoids interference from abnormal waveforms caused by deflation, thus connecting the last pressure wave of the previous pressure platform with the first pressure wave of the next pressure platform, achieving seamless and continuous pressure signal connection and shortening the blood pressure measurement cycle time. It also filters out interference information such as motion, reducing data computation, shortening data computation time, shortening the pressure holding time during step deflation, and improving comfort.

[0157] Although the invention has been described with reference to several typical embodiments, it should be understood that the terminology used is illustrative and exemplary, and not restrictive. Since the invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A method for detecting non-invasive blood pressure waveforms, characterized in that, The method includes: Inflate the cuffs strapped to the subject's limbs using an inflation device; The gas pressure inside the cuff is detected in real time by a cuff pressure sensor. After the gas pressure inside the cuff reaches the initial inflation pressure, the cuff is gradually deflated using a deflation device. The following steps are performed during the gradual deflation process: The gas pressure inside the cuff is controlled to be maintained at the first step pressure, and the first pressure oscillation waveform is obtained in real time using the cuff pressure sensor. At least two first pulse waveforms are detected from the first pressure oscillation waveform, the first pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat; Based on the at least two first pulse waveforms, a first search pressure fundamental wave is determined, wherein the step of determining the first search pressure fundamental wave based on the at least two first pulse waveforms is: merging the at least two first pulse waveforms to determine the first search pressure fundamental wave; The cuff is deflated using the aforementioned deflation device; During the deflation process, the second pressure oscillation waveform is obtained in real time using the cuff pressure sensor; Based on the first search pressure fundamental wave, the first second pulse waveform that matches the first search pressure fundamental wave in the second pressure oscillation waveform is detected in real time; Stop deflating and maintain the current pressure value in the cuff, which is the second-step pressure; Based on the detected first second pulse waveform, at least two third pulse waveforms are detected from the second pressure oscillation waveform, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat; The at least two first pulse waveforms and the at least two third pulse waveforms are converted into multiple sets of oscillation amplitude waveforms; and, The multiple sets of oscillation amplitude waveforms obtained after multiple deflations are combined to generate the blood pressure envelope curve.

2. The method for detecting non-invasive blood pressure waveforms according to claim 1, characterized in that, In the method, the step of detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform includes: After detecting the first second pulse waveform, continue searching for the peaks and troughs in the second pressure oscillation waveform to obtain at least two consecutive pressure pulse waveforms; Evaluate the similarity between the first second pulse waveform and the at least two consecutive pressure pulse waveforms; and, If the similarity reaches a preset value, then some or all of the at least two consecutive pressure pulse waveforms, together with the first second pulse waveform, are taken as the at least two third pulse waveforms.

3. The method for detecting non-invasive blood pressure waveforms according to claim 2, characterized in that, If the similarity reaches a preset value, the cuff is deflated again using the deflation device.

4. The method for detecting non-invasive blood pressure waveforms according to claim 1, characterized in that, In the method, the step of obtaining a first pressure oscillation waveform in real time using the cuff pressure sensor, or obtaining a second pressure oscillation waveform in real time using the cuff pressure sensor, includes: The initial pressure oscillation waveform is obtained in real time using the cuff pressure sensor. Slide the first moving window to acquire sample segments on the initial pressure oscillation waveform one by one; Extract the odd number of waveform data points within the sampled segment, sort them, and obtain the waveform data located in the middle position; Replace the last sample point data in the moving window with the waveform data; After processing each sampling point on the initial pressure oscillation waveform using the first moving window, a pressure trend signal is obtained; and, The first pressure oscillation waveform or the second pressure oscillation waveform is obtained by subtracting the pressure trend signal from the initial pressure oscillation waveform.

5. The method for detecting non-invasive blood pressure waveforms according to claim 1, characterized in that, The step of generating a blood pressure envelope curve from the multiple sets of oscillation amplitude waveforms obtained after multiple deflations includes: The multiple sets of oscillation amplitude waveforms obtained after multiple deflations are collected and arranged in chronological order to form a collection with time on the horizontal axis and amplitude on the vertical axis. Extract the first waveform data set of several oscillation amplitude waveforms before and after the first moment; The amplitude values ​​of the first waveform data set are weighted and averaged to obtain the first curve point, and the first curve point is associated with the first time point. Extract the second waveform data set of several oscillation amplitude waveforms before and after the second time point; The amplitude values ​​of the second waveform data set are weighted and averaged to obtain the second curve points, and the second curve points are associated with the second time point. The first waveform data set and the second waveform data set overlap but are not the same; and, Connect the first curve point and the second curve point to generate part or all of the envelope curve of the blood pressure.

6. The method for detecting non-invasive blood pressure waveforms according to claim 1, characterized in that, The process of converting the at least two first pulse waveforms and the at least two third pulse waveforms into multiple sets of oscillation amplitude waveforms includes: The at least two first pulse waveforms are combined to obtain the first oscillation pressure amplitude corresponding to the first step pressure; The at least two third pulse waveforms are combined to obtain the second oscillation pressure amplitude corresponding to the second step pressure; and, The sampling time points corresponding to the first and second oscillation pressure amplitudes are associated and marked to form the multiple sets of oscillation amplitude waveforms.

7. A non-invasive blood pressure measurement device, characterized in that, The device includes: Cuffs are used to bind the subject's limbs; An inflation device, which is connected to the cuff via an air passage, is used to inflate the cuff; An air release device is connected to the cuff via an air passage and is used to release air from the cuff. A cuff pressure sensor, located on the air path connecting the inflation and deflation devices to the cuff, is used to detect the gas pressure inside the cuff in real time and obtain a pressure oscillation waveform; and, A controller, electrically connected to the inflation device, deflation device, and cuff pressure sensor, controls the inflation device, deflation device, and cuff pressure sensor to perform the following process according to the method of claim 1: The inflatable device is used to inflate the cuffs strapped to the subject's limbs; The gas pressure inside the cuff is detected in real time by the cuff pressure sensor. After the gas pressure inside the cuff reaches the initial inflation pressure, the deflation device is used to gradually deflate the cuff. During the gradual deflation process, the following steps are performed: The gas pressure inside the cuff is controlled to be maintained at the first step pressure, and the first pressure oscillation waveform is obtained in real time using the cuff pressure sensor. At least two first pulse waveforms are detected from the first pressure oscillation waveform, the first pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat; Based on the at least two first pulse waveforms, a first search pressure fundamental wave is determined, wherein the step of determining the first search pressure fundamental wave based on the at least two first pulse waveforms is: merging the at least two first pulse waveforms to determine the first search pressure fundamental wave; The cuff is deflated using the aforementioned deflation device; During the deflation process, the second pressure oscillation waveform is obtained in real time using the cuff pressure sensor; Based on the first search pressure fundamental wave, the first second pulse waveform that matches the first search pressure fundamental wave in the second pressure oscillation waveform is detected in real time; Stop deflating and maintain the current pressure value in the cuff, which is the second-step pressure; Based on the detected first second pulse waveform, at least two third pulse waveforms are detected from the second pressure oscillation waveform, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff due to the subject's heartbeat; The at least two first pulse waveforms and the at least two third pulse waveforms are converted into multiple sets of oscillation amplitude waveforms; The multiple sets of oscillation amplitude waveforms obtained after multiple deflations are combined to generate the blood pressure envelope curve.

8. A non-invasive blood pressure measuring device according to claim 7, characterized in that: The device also includes an air container, which is a cavity structure containing multiple air holes. These air holes are connected to the cuff, inflation device, deflation device, and cuff pressure sensor via air tubes.

9. A non-invasive blood pressure measuring device according to claim 7, characterized in that: The detection of at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform includes: After detecting the first second pulse waveform, continue searching for the peaks and troughs in the second pressure oscillation waveform to obtain at least two consecutive pressure pulse waveforms; Evaluate the similarity between the first second pulse waveform and the at least two consecutive pressure pulse waveforms; and, If the similarity reaches a preset value, then some or all of the at least two consecutive pressure pulse waveforms, together with the first second pulse waveform, are taken as the at least two third pulse waveforms. And / or, the step of obtaining a first pressure oscillation waveform in real time using the cuff pressure sensor, or obtaining a second pressure oscillation waveform in real time using the cuff pressure sensor, includes: The initial pressure oscillation waveform is obtained in real time using the cuff pressure sensor. Slide the first moving window to acquire sample segments on the initial pressure oscillation waveform one by one; Extract the odd number of waveform data points within the sampled segment, sort them, and obtain the waveform data located in the middle position; Replace the last sample point data in the moving window with the waveform data; After processing each sampling point on the initial pressure oscillation waveform using the first moving window, a pressure trend signal is obtained; and, The first pressure oscillation waveform or the second pressure oscillation waveform is obtained by subtracting the pressure trend signal from the initial pressure oscillation waveform. And / or, the step of generating a blood pressure envelope curve from the multiple sets of oscillation amplitude waveforms obtained after multiple deflations of the set includes: The multiple sets of oscillation amplitude waveforms obtained after multiple deflations are collected and arranged in chronological order to form a collection with time on the horizontal axis and amplitude on the vertical axis. Extract the first waveform data set of several oscillation amplitude waveforms before and after the first moment; The amplitude values ​​of the first waveform data set are weighted and averaged to obtain the first curve point, and the first curve point is associated with the first time point. Extract the second waveform data set of several oscillation amplitude waveforms before and after the second time point; The amplitude values ​​of the second waveform data set are weighted and averaged to obtain the second curve points, and the second curve points are associated with the second time point. The first waveform data set and the second waveform data set overlap but are not the same; and, Connect the first curve point and the second curve point to generate part or all of the envelope curve of the blood pressure.

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