Non-invasive blood pressure waveform detection method and blood pressure measurement equipment

Abstract

The invention provides a non-invasive blood pressure waveform detection method and blood pressure measurement equipment. A cuff is used for being bound to a limb of a subject; the inflating device is communicated with the cuff through an air path and is used for inflating the cuff; the deflation device is communicated with the cuff through an air path and is used for deflating the cuff; the cuff pressure sensor is positioned on a communication air path between the inflating device and the cuff and between the deflating device and the cuff and is used for detecting the air pressure in the cuff in real time to obtain a pressure oscillation waveform; the controller is electrically connected with the inflation device, the deflation device and the cuff pressure sensor, and the controller controls the inflation device, the deflation device and the cuff pressure sensor to execute inflation and deflation processes for the cuff according to the non-invasive blood pressure waveform detection method provided by the invention, and generates an envelope curve of blood pressure. According to the scheme, the cycle time of blood pressure measurement is shortened.

Description

Technical Field

[0001] The present invention relates to the field of medical monitoring technology, and in particular to a non-invasive blood pressure waveform detection method and a blood pressure measurement device. Background Art

[0002] Blood pressure measurement includes obtaining the maximum arterial pressure caused by cardiac contraction and the minimum arterial pressure value during cardiac diastole, that is, systolic pressure and diastolic pressure. Blood pressure parameters are important physiological parameters that can reflect the various functional conditions of the human heart, cardiovascular and cerebrovascular systems, and have a high reference value for preventing various related diseases. Currently, the methods for measuring blood pressure are mainly divided into two measurement methods: invasive blood pressure (Invasive Blood Pressure, IBP) and non-invasive blood pressure (None Invasive Blood Pressure, NIBP). IBP measurement is accurate, but it is somewhat harmful and not conducive to daily measurement. It is only used more in critically ill patients. Non-invasive blood pressure is non-invasive, and the measurement is becoming more and more accurate, convenient and practical, so it is currently widely used in daily measurements. The current NIBP measurement method is mainly based on the principle of oscillometric method. The principle is to squeeze the blood vessels by inflating and deflation of the cuff wrapped around the upper arm, and collect the real-time pulse wave change curve through the pressure sensor. The mean pressure (Mp), systolic pressure (Sp), diastolic pressure (Dp) and pulse rate (PR) of blood pressure are calculated according to the law of the pulse wave peak curve, and finally the measurement results are displayed through the human-computer interface. Because the pulse wave signal is weak and easily interfered, and the measurement inevitably introduces a lot of noise, this has an adverse effect on the calculation of blood pressure parameters. The control of the inflation and deflation of the cuff and the related processing during the inflation and deflation process are also directly related to the accuracy, comfort and applicability of blood pressure measurement.

[0003] Existing NIBP measurement based on the oscillometric method usually adopts step-deflation. Step-deflation measurement is to first inflate, maintain pressure, and then gradually deflate. Each step-deflation pressure stage needs to be maintained for a certain time, resulting in disadvantages such as long measurement time and low measurement comfort, and is not conducive to people who are sensitive to air pressure pressure. Summary of the invention

[0004] The object of the present invention is to provide a non-invasive blood pressure waveform detection method and a blood pressure measurement device to solve the problems of long time and poor comfort of step-deflation blood pressure measurement in the prior art.

[0005] In order to solve the above technical problems, the present invention provides a method for detecting a non-invasive blood pressure waveform, the method comprising:

[0006] Inflate a cuff tied to a limb of the subject using an inflating device;

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

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

[0009] Controlling the gas pressure in the cuff to maintain at a first step pressure, and obtaining a first pressure oscillation waveform in real time using the cuff pressure sensor;

[0010] detecting at least two first pulse waveforms from the first pressure oscillation waveform, the first pulse waveform being pressure fluctuations caused by pressure changes in the cuff due to a heartbeat of the subject;

[0011] determining a first search pressure fundamental wave based on the at least two first pulse waveforms;

[0012] Deflating the cuff using the deflation device;

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

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

[0015] detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff caused by a heartbeat of the subject;

[0016] converting the at least two first pulse waveforms and the at least two third pulse waveforms into a plurality of sets of oscillation amplitude waveforms; and,

[0017] The multiple groups of oscillation amplitude waveforms obtained after multiple deflations are collected to generate an envelope curve of blood pressure.

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

[0019] Stop deflation and maintain the current pressure value in the cuff, and execute 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, 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 comprises:

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

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

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

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

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

[0026] Using the cuff pressure sensor to obtain an initial pressure oscillation waveform in real time;

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

[0028] Extracting an odd number of waveform data in the sampling segment, sorting them, and obtaining waveform data located in the middle position;

[0029] Replace the last sampling 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 an envelope curve of blood pressure by combining the multiple groups of oscillation amplitude waveforms obtained after multiple deflations comprises:

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

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

[0035] Performing weighted average calculation on the amplitude values ​​of the first waveform data set to obtain a first curve point, and associating the first curve point with the first moment;

[0036] Extracting a second waveform data set of several oscillation amplitude waveforms before and after a second moment;

[0037] Performing weighted average calculation on the amplitude values ​​of the second waveform data set to obtain a second curve point, and associating the second curve point with the second moment;

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

[0039] The first curve point and the second curve point are connected 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 a plurality of sets of oscillation amplitude waveforms comprises:

[0041] Combining the at least two first pulse waveforms to obtain a first oscillation pressure amplitude corresponding to the first step pressure;

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

[0043] The sampling time points corresponding to the first oscillation pressure amplitude and the second oscillation pressure amplitude are respectively marked in association to form the multiple groups of oscillation amplitude waveforms.

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

[0045] A cuff, for strapping around a subject's limb;

[0046] An inflating device, the inflating device is connected to the cuff through an air path and is used to inflate the cuff;

[0047] a deflation device, the deflation device being in communication with the cuff via an air path and being used for deflation of the cuff;

[0048] a cuff pressure sensor, the cuff pressure sensor being located on the communicating air path between the inflation device and the deflation device and the cuff, and being used for detecting the gas pressure in the cuff in real time to obtain a pressure oscillation waveform; and,

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

[0050] Using the inflation device to inflate the cuff tied to the subject's limb;

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

[0052] After the gas pressure in the cuff reaches the initial inflation pressure, the cuff is gradually deflated by using the deflation device, and the following steps are performed during the gradual deflation process:

[0053] Controlling the gas pressure in the cuff to maintain at a first step pressure, and obtaining a first pressure oscillation waveform in real time using the cuff pressure sensor;

[0054] detecting at least two first pulse waveforms from the first pressure oscillation waveform, the first pulse waveform being pressure fluctuations caused by pressure changes in the cuff due to a heartbeat of the subject;

[0055] determining a first search pressure fundamental wave based on the at least two first pulse waveforms;

[0056] Deflating the cuff using the deflation device;

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

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

[0059] detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff caused by a heartbeat of the subject;

[0060] converting the at least two first pulse waveforms and the at least two third pulse waveforms into a plurality of groups of oscillation amplitude waveforms;

[0061] The multiple groups of oscillation amplitude waveforms obtained after multiple deflations are collected to generate an envelope curve of blood pressure.

[0062] In one embodiment, the device further comprises an air container, which is a cavity structure, and the cavity structure comprises a plurality of air holes, and the plurality of air holes are respectively connected to the cuff, the inflation device, the deflation device and the cuff pressure sensor through an air tube for air communication.

[0063] In one embodiment, 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 comprises:

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

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

[0066] If the similarity reaches a preset value, part or all of the at least two continuous pressure pulse waveforms, together with the first second pulse waveform, are used as the at least two third pulse waveforms;

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

[0068] Using the cuff pressure sensor to obtain an initial pressure oscillation waveform in real time;

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

[0070] Extracting an odd number of waveform data in the sampling segment, sorting them, and obtaining waveform data located in the middle position;

[0071] Replace the last sampling 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] Subtracting the pressure trend signal from the initial pressure oscillation waveform to obtain the first pressure oscillation waveform or the second pressure oscillation waveform;

[0074] And / or, the step of generating an envelope curve of blood pressure from the multiple groups of oscillation amplitude waveforms obtained after multiple deflations comprises:

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

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

[0077] Performing weighted average calculation on the amplitude values ​​of the first waveform data set to obtain a first curve point, and associating the first curve point with the first moment;

[0078] Extracting a second waveform data set of several oscillation amplitude waveforms before and after a second moment;

[0079] Performing weighted average calculation on the amplitude values ​​of the second waveform data set to obtain a second curve point, and associating the second curve point with the second moment;

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

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

[0082] The non-invasive blood pressure waveform detection method provided by the present invention realizes rapid detection through the pulse waveform detected under adjacent step pressures, without having to wait for the deflation step pressure to stabilize during the deflation process before starting the pulse wave detection. Doing so can save the time of waiting for the pressure to stabilize before sampling during each deflation process. In addition, it can also avoid abnormal waveform interference caused by deflation, thereby stringing together the last pressure wave of the previous pressure platform and the first pressure wave of the next pressure platform, thereby realizing seamless and continuous connection of pressure signals, shortening the cycle time of blood pressure measurement, shortening the pressure holding time of step deflation, and improving comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 It is a structural schematic diagram of the blood pressure measuring device in the present invention.

[0084] Figure 2 It is a flow chart of the non-invasive blood pressure waveform detection method of the present invention.

[0085] Figure 3 Schematic diagram of the process waveform of the detection method of the present invention, wherein (a) is the initial pressure oscillation waveform; (b) the oscillation waveform after treatment; (c) the amplitude change waveform; and (d) the envelope curve of blood pressure. DETAILED DESCRIPTION

[0086] Typical embodiments that embody 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 changes in different embodiments without departing from the scope of the present invention, and the descriptions and illustrations therein are essentially used for illustration purposes rather than for limiting the present invention.

[0087] In order to further illustrate the principle and structure of the present invention, preferred embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0088] The present invention is based on the improvement of a non-invasive blood pressure measuring device, and in particular is aimed at improving a non-invasive blood pressure waveform detection method in the non-invasive blood pressure measuring 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 be tied to the subject's limb;

[0091] The inflating device 330 is in communication with the cuff 310 via an air path, and is used to inflate the cuff 310;

[0092] The deflation device 340 is in communication with the cuff 310 via an air path, and is used to deflate the cuff 310;

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

[0094] The controller 320 is electrically connected to the inflation device 330, the deflation device 340 and the cuff pressure sensor 350, and the controller 320 controls the inflation device 330, the deflation device 340 and the cuff pressure sensor 350 to perform inflation and deflation processes for the cuff 310 according to the non-invasive blood pressure waveform detection method proposed by the present invention, and generates an envelope curve of the blood pressure (such as Figure 3 800), based on the envelope curve, a blood pressure measurement value is obtained for display on the display 360. Based on the peak value, rising edge and falling edge of the blood pressure envelope curve 800, the average blood pressure, diastolic pressure and systolic pressure values ​​can be calculated. The deflation device 340 is connected to the outside. When the deflation device 340 is opened, the deflation device 340 is connected to the atmosphere to deflate the cuff. When the deflation device 340 is closed, the deflation device 340 is not connected to the atmosphere, and the cuff is prohibited from deflation.

[0095] like Figure 1As shown, in some embodiments of the present invention, in order to ensure the stability of the air pressure on the connected air path, to facilitate the collection of more accurate information, especially to capture the slight pressure change in the cuff caused by the heartbeat, an air container 380 may be added to the above device. The air container 380 is a cavity structure, and the cavity structure includes a plurality of air holes. The plurality of air holes are respectively connected to the cuff 310, the inflation device 330, the deflation device 340 and the cuff pressure sensor 350 through the air tube. In other words, the cuff 310, the inflation device 330, the deflation device 340 and the cuff pressure sensor 350 are connected to the cuff 310 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, and the pump is connected to the cuff 310 through an air circuit; the pump is electrically connected to the controller 320; and 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, the multiple air holes on the air container 380 are connected to the cuff 310, the pump, and the cuff pressure sensor 350 through an air pipe. 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 opened, 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 through an air path; the deflation valve is electrically connected to the controller 320; the controller 320 sends a start and a stop signal to the deflation valve, so as to realize the inflation and deflation of the cuff 310 in the non-invasive blood pressure waveform detection method proposed in the present invention. When the inflation device (i.e., the pump) is started and the deflation device is turned off, the cuff is inflated; when the inflation device (i.e., the pump) is turned off and the deflation device is turned on, the cuff is deflated. Based on this design, in some embodiments of the present invention, the multiple air holes on the air container 380 are respectively connected to the cuff 310, the deflation valve and the cuff pressure sensor 350 through the trachea for air path.

[0098] like Figure 1As shown, in some embodiments of the present invention, the cuff pressure sensor 350 may include one pressure sensor, or multiple 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 the pressure signal (such as pressure value and / or pressure oscillation waveform) collected on the air path to the controller 320, and the cuff inflation pressure sensor 351 is located on the air path connecting the inflation device 330 and the cuff 310. The cuff deflation pressure sensor 352 is located on the air path connecting the deflation device 340 and the cuff 310. The use of separate air pressure sensors can collect cuff pressure values ​​and / or pressure oscillation waveforms more accurately and timely. Based on this design, in some embodiments of the present invention, the multiple air holes on the air container 380 are connected to the cuff inflation pressure sensor 351 and the cuff deflation pressure sensor 352 through the air tube for air path communication. For example, Figure 1 As shown, in some embodiments of the present invention, the multiple air holes on the air container 380 are connected to the cuff 310, the deflation valve, the pump, the cuff inflation pressure sensor 351 and the cuff deflation pressure sensor 352 through the air pipe. In the above embodiments, the deflation device (such as the deflation valve) needs to be connected to the atmospheric pressure to realize the inflation and deflation process. When the deflation valve is opened, the aforementioned communication air path is connected to the atmospheric pressure to realize deflation. Conversely, when inflating, the deflation valve is closed.

[0099] based on Figure 1 Blood pressure measuring equipment such as Figure 2 As shown, the present invention provides a method for detecting a non-invasive blood pressure waveform on the aforementioned non-invasive blood pressure measurement device, which 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 uses the inflation device 330 to inflate the cuff 310; and step 200: the controller 320 uses the deflation device 340 to deflate the cuff 310 and obtains the envelope curve 800 of the blood pressure.

[0100] In step 100, when the controller 320 uses the inflation device 330 to inflate the cuff 310, the controller 320 adopts the following steps:

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

[0102] Step 120 : Detect the gas pressure in the cuff 310 in real time via the cuff pressure sensor 350 .

[0103] Step 130: Determine whether the gas pressure in the cuff 310 has reached the initial inflation pressure; in step 200, the controller 320 uses the deflation device 340 to deflate the cuff 310 and obtain the envelope curve of the blood pressure. After the gas pressure in the cuff 310 has reached the initial inflation pressure, the deflation device 340 is used to successively deflate the cuff 310. During the successive deflation process, the controller 320 performs the following steps 210 to 290. If the gas pressure in the cuff 310 has not reached the initial inflation pressure, return to step 110: inflate the cuff 310 tied to the subject's limb using the inflation device 330.

[0104] like Figure 2 and Figure 3 As shown, during the process of successive deflation, the controller 320 performs the following steps 210 to 290, which are as follows:

[0105] Step 210: Control the gas pressure in the cuff 310 to maintain at the first step pressure 410, and use the cuff pressure sensor 350 to obtain a 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, wherein the first pulse waveform is a pressure fluctuation caused by a pressure change in the cuff caused by the heartbeat of the subject;

[0107] Step 230: Determine a first search pressure fundamental wave 620 based on the at least two first pulse waveforms;

[0108] Step 240: Deflate the cuff 310 using the deflation device 340;

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

[0110] Step 260: Based on the first search pressure fundamental wave 620, real-time detection of 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, detecting at least two third pulse waveforms from the second pressure oscillation waveform 640, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff caused by 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 a plurality of groups of oscillation amplitude waveforms 700;

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

[0114] In some embodiments of the present invention, during the above-mentioned steps 210 to 290 , the controller 320 may utilize 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 the present invention realizes rapid detection through the pulse waveform detected under adjacent step pressures, without having to wait for the deflation step pressure to stabilize before starting the pulse wave detection. This can save the time of waiting for the pressure to stabilize before sampling during each deflation process. In addition, it can also avoid abnormal waveform interference caused by deflation, thereby stringing the last pressure wave of the front pressure platform with the first pressure wave of the next pressure platform, thereby realizing seamless and continuous connection of the pressure signal and shortening the cycle time of blood pressure measurement. The present invention also shortens the pressure holding time of step deflation and improves comfort.

[0116] In some embodiments of the present invention, Figure 3 As shown, in the aforementioned step 260, 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, execute 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 in real time the first second pulse waveform 630 matching the first search pressure fundamental wave 620 in the second pressure oscillation waveform 640 based on the first search pressure fundamental wave 620 in the aforementioned step 260 can be implemented in the following manner:

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

[0120] Determine whether the searched pressure pulse waveform is similar to the first searched pressure fundamental wave 620. If similar, the currently searched pressure pulse wave is regarded as the first second pulse waveform 630. If not similar, repeat the step of searching 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 real-time detection of the first second pulse waveform matching the first search pressure fundamental wave in the second pressure oscillation waveform, it is not necessary to perform the above-mentioned process of stopping deflation and maintaining the current pressure value in the cuff, that is, it is not necessary to maintain the second step pressure 420 for too long to achieve deflation again, or it is possible to obtain multiple similar pressure pulse waveforms in an extreme time after searching for the first second pulse waveform, so it is not necessary to maintain the second step pressure 420, and continuous deflation can be achieved. This further shortens the deflation detection time.

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

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

[0124] Determine whether the amplitude and frequency between two adjacent pressure pulse waveforms among the at least three pressure pulse waveforms searched are similar. If so, it indicates that the at least two first pulse waveforms have been detected, and select at least two from the at least three pressure pulse waveforms searched as the at least two first pulse waveforms. Otherwise, if not similar, repeat 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, until the step of determining whether the amplitude and frequency between two adjacent pressure pulse waveforms among the at least three pressure pulse waveforms searched are similar.

[0125] In some embodiments of the present invention, Figure 3 As shown, the aforementioned step 230: determining the first search pressure fundamental wave 620 based on the at least two first pulse waveforms is implemented by the following process:

[0126] The at least two first pulse waveforms are combined to determine the first search pressure fundamental wave 620, and the combination may be performed by averaging; or,

[0127] From the at least two first pulse waveforms, one closest in time is selected 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 the pressure oscillation waveform.

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

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

[0131] evaluating 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, part or all of the at least two continuous pressure pulse waveforms, together with the first second pulse waveform 630, are used as the at least two third pulse waveforms.

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

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

[0135] In some embodiments of the present invention, Figure 3 As shown, in order to further improve the measurement speed, in the aforementioned 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 by using the deflation device 340. Therefore, by comparing the similarity with the adjacent waveform (the waveform under the previous step pressure platform), a fast deflation strategy can be implemented without the problem of continuously waiting for the step pressure platform and without calculating the DC direct current component, thereby shortening the measurement time.

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

[0137] The cuff pressure sensor 350 is used to obtain an initial pressure oscillation waveform in real time. For example, in step 210, the cuff pressure sensor 350 is used to obtain a first pressure oscillation waveform 510 in real time. For example, in step 250, the cuff pressure sensor 350 is used to obtain a second pressure oscillation waveform 520 in real time.

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

[0139] Extracting an odd number of waveform data in the sampling segment, sorting them, and obtaining waveform data located in the middle position;

[0140] Replace the last sampling 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] After processing the initial pressure oscillation waveform (510, 520) in this way, the influence of the blood echo wave can be eliminated and the effective signal of the cardiac ejection segment can be extracted; moreover, the large drop signal in the deflation stage between the pressure platforms can be quickly suppressed; thereby, the last pressure wave of the front platform and the first pressure wave of the rear platform are connected in series, thereby realizing seamless and continuous connection of the pressure signal and shortening the platform cycle.

[0144] In some embodiments of the present invention, 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 groups of oscillation amplitude waveforms in the aforementioned step 280 includes:

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

[0146] Combining the at least two third pulse waveforms detected on the second pressure oscillation waveform 640 to obtain a second oscillation pressure amplitude 720 corresponding to the second step pressure 420; and,

[0147] The sampling time points corresponding to the first oscillation pressure amplitude 710 and the second oscillation pressure amplitude 720 are respectively marked in association to form the plurality of groups of oscillation amplitude waveforms 700, such as Figure 3 (c) in .

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

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

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

[0151] Performing weighted average calculation on the amplitude values ​​of the first waveform data set to obtain a first curve point E, and associating the first curve point E with the first moment A;

[0152] Extracting a second waveform data set of several oscillation amplitude waveforms before and after a second moment B;

[0153] Performing weighted average calculation on the amplitude values ​​of the second waveform data set to obtain a second curve point F, and associating the second curve point F with the second moment B; and,

[0154] The first curve point E and the second curve point F are connected to generate part or all of the envelope curve 800 of the blood pressure, and the first waveform data set and the second waveform data set overlap, but are not the same. The above curve fitting method has the advantage 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 the weighted average of more than five adjacent data points to calculate the smoothed data points can retain the trend information of the data while eliminating noise and reduce the amount of data calculation.

[0155] In the similarity evaluation or matching judgment mentioned in the method of the present invention, the amplitude, amplitude change, frequency, waveform shape, etc. of the waveform can be compared with a threshold or a preset waveform to perform similarity judgment. The similarity judgment can be the same or approximately the same.

[0156] It can be seen from the above technical scheme that the advantages and positive effects of the present invention are: rapid detection is achieved through the pulse waveform detected under adjacent step pressures, without having to wait for the deflation step pressure to stabilize before starting the pulse wave detection. This can save the time of waiting for the pressure to stabilize before sampling during each deflation process. In addition, it can also avoid abnormal waveform interference caused by deflation, thereby stringing the last pressure wave of the front pressure platform with the first pressure wave of the next pressure platform, thereby achieving seamless and continuous connection of the pressure signal and shortening the cycle time of blood pressure measurement. It can also filter out interference information such as movement, reduce the amount of data calculation, shorten the data calculation time, shorten the pressure holding time of step deflation, and improve comfort.

[0157] Although the present invention has been described with reference to several typical embodiments, it should be understood that the terms used are illustrative and exemplary, rather than restrictive. Since the present invention can be embodied in a variety of 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, so all changes 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 a non-invasive blood pressure waveform, characterized in that: The method comprises: Inflate a cuff tied to a limb of the subject using an inflating device; The gas pressure in the cuff is detected in real time by a cuff pressure sensor. After the gas pressure in the cuff reaches the initial inflation pressure, the cuff is gradually deflated using the deflation device, and the following steps are performed during the gradual deflation process: Controlling the gas pressure in the cuff to maintain at a first step pressure, and obtaining a first pressure oscillation waveform in real time using the cuff pressure sensor; detecting at least two first pulse waveforms from the first pressure oscillation waveform, the first pulse waveform being pressure fluctuations caused by pressure changes in the cuff due to a heartbeat of the subject; determining a first search pressure fundamental wave based on the at least two first pulse waveforms; Deflating the cuff using the deflation device; During the deflation process, a second pressure oscillation waveform is obtained in real time using the cuff pressure sensor; Based on the first search pressure fundamental wave, real-time detection of the first second pulse waveform in the second pressure oscillation waveform that matches the first search pressure fundamental wave; detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff caused by a heartbeat of the subject; converting the at least two first pulse waveforms and the at least two third pulse waveforms into a plurality of sets of oscillation amplitude waveforms; and, The multiple groups of oscillation amplitude waveforms obtained after multiple deflations are collected to generate an envelope curve of blood pressure.

2. The method for detecting a non-invasive blood pressure waveform according to claim 1, characterized in that: Based on the first search pressure fundamental wave, the first second pulse waveform matching the first search pressure fundamental wave in the second pressure oscillation waveform is detected in real time, and then the method further includes: Stop deflation and maintain the current pressure value in the cuff, and execute the step of detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform.

3. A non-invasive blood pressure waveform detection method according to claim 1 or 2, 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 comprises: After detecting the first second pulse waveform, continue searching for peaks and troughs in the second pressure oscillation waveform to obtain at least two consecutive pressure pulse waveforms; evaluating the similarity of the first second pulse waveform and the at least two consecutive pressure pulse waveforms; and, If the similarity reaches a preset value, part or all of the at least two continuous pressure pulse waveforms, together with the first second pulse waveform, are used as the at least two third pulse waveforms.

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

5. The method for detecting a non-invasive blood pressure waveform according to claim 1, characterized in that: In the method, the step of obtaining the first pressure oscillation waveform in real time by using the cuff pressure sensor, or obtaining the second pressure oscillation waveform in real time by using the cuff pressure sensor comprises: Using the cuff pressure sensor to obtain an initial pressure oscillation waveform in real time; Sliding the first moving window to acquire sampling segments on the initial pressure oscillation waveform one by one; Extracting an odd number of waveform data in the sampling segment, sorting them, and obtaining waveform data located in the middle position; Replace the last sampling 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.

6. The method for detecting a non-invasive blood pressure waveform according to claim 1, characterized in that: The step of collecting the multiple groups of oscillation amplitude waveforms obtained after multiple deflations to generate an envelope curve of blood pressure comprises: The multiple groups of oscillation amplitude waveforms obtained after multiple deflations are collected and arranged in chronological order to form a collection with the horizontal axis being time and the vertical axis being amplitude; Extracting a first waveform data set of several oscillation amplitude waveforms before and after a first moment; Performing weighted average calculation on the amplitude values ​​of the first waveform data set to obtain a first curve point, and associating the first curve point with the first moment; Extracting a second waveform data set of several oscillation amplitude waveforms before and after a second moment; Performing weighted average calculation on the amplitude values ​​of the second waveform data set to obtain a second curve point, and associating the second curve point with the second moment; The first waveform data set and the second waveform data set overlap but are not identical; and, The first curve point and the second curve point are connected to generate part or all of the envelope curve of the blood pressure.

7. The method for detecting a non-invasive blood pressure waveform 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 a plurality of groups of oscillation amplitude waveforms comprises: Combining the at least two first pulse waveforms to obtain a first oscillation pressure amplitude corresponding to the first step pressure; combining the at least two third pulse waveforms to obtain a second oscillation pressure amplitude corresponding to the second step pressure; and, The sampling time points corresponding to the first oscillation pressure amplitude and the second oscillation pressure amplitude are respectively marked in association to form the multiple groups of oscillation amplitude waveforms.

8. A non-invasive blood pressure measurement device, characterized in that: The device comprises: A cuff, for strapping around a subject's limb; An inflating device, the inflating device is connected to the cuff through an air path and is used to inflate the cuff; a deflation device, the deflation device being in communication with the cuff via an air path and being used for deflation of the cuff; a cuff pressure sensor, the cuff pressure sensor being located on the communicating air path between the inflation device and the deflation device and the cuff, and being used for detecting the gas pressure in the cuff in real time to obtain a pressure oscillation waveform; and, A controller is electrically connected to the inflation device, the deflation device and the cuff pressure sensor, and the controller controls the inflation device, the deflation device and the cuff pressure sensor to perform the following process: Using the inflation device to inflate the cuff tied to the subject's limb; The gas pressure in the cuff is detected in real time by the cuff pressure sensor. After the gas pressure in the cuff reaches the initial inflation pressure, the cuff is gradually deflated by using the deflation device, and the following steps are performed during the gradual deflation process: Controlling the gas pressure in the cuff to maintain at a first step pressure, and obtaining a first pressure oscillation waveform in real time using the cuff pressure sensor; detecting at least two first pulse waveforms from the first pressure oscillation waveform, the first pulse waveform being pressure fluctuations caused by pressure changes in the cuff due to a heartbeat of the subject; determining a first search pressure fundamental wave based on the at least two first pulse waveforms; Deflating the cuff using the deflation device; During the deflation process, a second pressure oscillation waveform is obtained in real time using the cuff pressure sensor; Based on the first search pressure fundamental wave, real-time detection of the first second pulse waveform in the second pressure oscillation waveform that matches the first search pressure fundamental wave; detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform, the third pulse waveforms being pressure fluctuations caused by pressure changes in the cuff caused by a heartbeat of the subject; converting the at least two first pulse waveforms and the at least two third pulse waveforms into a plurality of groups of oscillation amplitude waveforms; The multiple groups of oscillation amplitude waveforms obtained after multiple deflations are collected to generate an envelope curve of blood pressure.

9. The non-invasive blood pressure measurement device according to claim 1, characterized in that: The device also includes an air container, which is a cavity structure. The cavity structure includes a plurality of air holes, and the plurality of air holes are respectively connected to the cuff, the inflation device, the deflation device and the cuff pressure sensor through air pipes.

10. The non-invasive blood pressure measurement device according to claim 1, characterized in that: The detecting at least two third pulse waveforms from the second pressure oscillation waveform based on the detected first second pulse waveform comprises: After detecting the first second pulse waveform, continue searching for peaks and troughs in the second pressure oscillation waveform to obtain at least two consecutive pressure pulse waveforms; evaluating the similarity of the first second pulse waveform and the at least two consecutive pressure pulse waveforms; and, If the similarity reaches a preset value, part or all of the at least two continuous pressure pulse waveforms, together with the first second pulse waveform, are used as the at least two third pulse waveforms; And / or, the step of obtaining the first pressure oscillation waveform in real time by using the cuff pressure sensor, or obtaining the second pressure oscillation waveform in real time by using the cuff pressure sensor includes: Using the cuff pressure sensor to obtain an initial pressure oscillation waveform in real time; Sliding the first moving window to acquire sampling segments on the initial pressure oscillation waveform one by one; Extracting an odd number of waveform data in the sampling segment, sorting them, and obtaining waveform data located in the middle position; Replace the last sampling 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, Subtracting the pressure trend signal from the initial pressure oscillation waveform to obtain the first pressure oscillation waveform or the second pressure oscillation waveform; And / or, the step of generating an envelope curve of blood pressure from the multiple groups of oscillation amplitude waveforms obtained after multiple deflations comprises: The multiple groups of oscillation amplitude waveforms obtained after multiple deflations are collected and arranged in chronological order to form a collection with the horizontal axis being time and the vertical axis being amplitude; Extracting a first waveform data set of several oscillation amplitude waveforms before and after a first moment; Performing weighted average calculation on the amplitude values ​​of the first waveform data set to obtain a first curve point, and associating the first curve point with the first moment; Extracting a second waveform data set of several oscillation amplitude waveforms before and after a second moment; Performing weighted average calculation on the amplitude values ​​of the second waveform data set to obtain a second curve point, and associating the second curve point with the second moment; The first waveform data set and the second waveform data set overlap but are not identical; and, The first curve point and the second curve point are connected to generate part or all of the envelope curve of the blood pressure.

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