Heartbeat simulation method and system for organ perfusion

Abstract

The invention discloses a heartbeat simulation method and a heartbeat simulation system for organ perfusion, rotating speeds corresponding to diastolic pressure and systolic pressure set by a user are calculated through a PID (Proportion Integration Differentiation) control algorithm, and a real-time rotating speed sequence is constructed based on a standard blood pressure value sequence, so that a heartbeat process can be accurately simulated. Meanwhile, according to the method and the system disclosed by the invention, only the adjustment of the PID control algorithm is carried out twice when the diastolic pressure and the systolic pressure are set by the user, and the operation is carried out by referring to the real-time rotating speed sequence in the subsequent working time, so that the pressure change caused by vascular obstruction or vascular rupture can be ensured under the condition of unattended operation. The organ perfusion equipment cannot adjust the rotating speed according to the current pressure feedback, so that secondary injury of blood vessels caused by PID rotating speed overshoot is avoided.

Description

Technical Field

[0001] The invention belongs to the medical field, and in particular relates to a heartbeat simulation method and system for organ perfusion. Background Art

[0002] Organ transplantation is an important means of treating patients with organ failure, and how to maintain the function and activity of the organ from organ harvesting to transplantation is a key factor affecting the success rate of transplantation. At present, organ preservation mainly relies on static cold preservation technology, which is to place the organ in a low-temperature preservation solution to reduce the metabolic rate to maintain the survival of the organ. However, this method cannot provide blood circulation, lacks oxygen and nutrient supply, and it is difficult to maintain the normal physiological state of the organ. It is also easy to cause ischemia-reperfusion injury under long-term preservation, which significantly limits the preservation time and functional integrity of the organ.

[0003] In order to overcome the limitations of traditional cold preservation, in vitro perfusion technology has gradually become one of the important means of organ preservation. This technology simulates blood circulation by placing the ex vivo organ in an oxygenated perfusion fluid to maintain the metabolic activity and function of the organ. Different from simple continuous flow perfusion, pulsatile perfusion can be closer to the physiological blood circulation state of the human body. Through periodic changes in blood flow pressure, it improves the microcirculation of the organ and the oxygen supply to the cells, thereby improving the preservation quality of the organ.

[0004] At present, the perfusion method of simulating heartbeat is mainly achieved through pulsating pumps, centrifugal pump regulation and pneumatic pulse systems. For example, the pulsating pump periodically drives the flow of perfusion fluid through a mechanical structure, directly generating blood flow with pulse characteristics; the centrifugal pump realizes periodic fluctuations in flow and pressure through continuous flow combined with a control device, thereby simulating the contraction and relaxation process of the heart. However, the existing heartbeat simulation technology still has certain limitations. It is unable to accurately simulate the blood flow waveform of a natural heartbeat, and the effect of pulsating perfusion is quite different from the physiological state of the human body. In addition, the complexity and stability of system control need to be further optimized, especially during long-term perfusion. If the pressure is not properly controlled, it may also cause damage to organ blood vessels.

[0005] Therefore, there is an urgent need for a more efficient, accurate and stable organ perfusion heartbeat simulation method that can truly restore the hemodynamic characteristics of the human heart in order to improve the quality of organ preservation and the success rate of transplantation. Summary of the invention

[0006] The present invention provides a heartbeat simulation method and system for organ perfusion, so as to solve the problem in the prior art that heartbeat simulation for organ perfusion cannot be provided efficiently, accurately and stably. In order to solve the above technical problems, the embodiments of the present invention disclose the following technical solutions: One aspect of the present invention provides a heartbeat simulation method for organ perfusion, which is applied to an organ perfusion device provided with a centrifugal pump, and the method comprises: After receiving the pressure adjustment instruction input by the user, the speed of the centrifugal pump is adjusted using a PID control algorithm according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and the current speed of the centrifugal pump is used as the diastolic pressure speed; Based on the systolic pressure value in the pressure adjustment instruction, the rotation speed of the centrifugal pump is adjusted by using a PID control algorithm until the pressure value of the blood pumped out by the centrifugal pump is equal to the systolic pressure value, and the current rotation speed of the centrifugal pump is used as the systolic pressure rotation speed; Construct a real-time speed sequence based on the diastolic speed, systolic speed and a preset standard blood pressure value sequence; Control the centrifugal pump to adjust the speed according to the real-time speed sequence.

[0007] Optionally, before executing the step of, after receiving the pressure adjustment instruction input by the user, adjusting the rotation speed of the centrifugal pump using a PID control algorithm according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and using the current rotation speed of the centrifugal pump as the diastolic pressure rotation speed, the method further includes: Determine whether a pressure adjustment instruction input by the user is received, If yes, obtain the diastolic pressure value and the systolic pressure value in the pressure adjustment instruction; If not, the centrifugal pump is controlled to adjust the speed according to the current real-time speed sequence.

[0008] Optionally, after receiving the pressure adjustment instruction input by the user, the rotation speed of the centrifugal pump is adjusted using a PID control algorithm according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and the current rotation speed of the centrifugal pump is used as the diastolic pressure rotation speed, including: Compare the pressure value of the blood currently pumped out by the centrifugal pump with the diastolic pressure value in the pressure adjustment instruction, and adjust the speed of the centrifugal pump using a PID control algorithm according to the comparison result; The pressure value of the blood pumped out by the centrifugal pump is continuously monitored, and the speed of the centrifugal pump corresponding to the pressure value being equal to the diastolic pressure value in the pressure adjustment instruction is used as the diastolic pressure speed.

[0009] Optionally, the adjusting the rotation speed of the centrifugal pump using a PID control algorithm based on the systolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped out by the centrifugal pump is equal to the systolic pressure value, and using the current rotation speed of the centrifugal pump as the systolic pressure rotation speed, includes: Compare the pressure value of the blood currently pumped out by the centrifugal pump with the systolic pressure value in the pressure adjustment instruction, and adjust the speed of the centrifugal pump using a PID control algorithm according to the comparison result; The pressure value of the blood pumped out by the centrifugal pump is continuously monitored, and the corresponding centrifugal pump speed when the pressure value is equal to the systolic pressure value in the pressure adjustment instruction is used as the systolic pressure speed.

[0010] Optionally, before executing the step of constructing a real-time rotation speed sequence based on the diastolic pressure rotation speed, the systolic pressure rotation speed and a preset standard blood pressure value sequence, the method further includes: Obtain the arterial blood pressure waveform curve of a single heartbeat in healthy people; Deleting the portion of the waveform curve where the blood pressure value is less than a preset lower limit; Selecting a preset number of segmentation points on the remaining waveform curves at the same time interval; All segmentation points and the start and end points of the waveform curve are regarded as sequence points; In order from the starting point to the ending point, a standard blood pressure value sequence is constructed based on the blood pressure value corresponding to each sequence point.

[0011] Optionally, selecting a preset number of segmentation points at the same time interval on the remaining waveform curve includes: The remaining waveform curve is digitized to obtain discrete data points, each of which corresponds to a blood pressure value; A preset point plotting method is used to obtain a characteristic point from all data points, wherein the blood pressure value corresponding to the characteristic point is greater than the blood pressure values ​​of two adjacent data points, or the blood pressure value corresponding to the characteristic point is less than the blood pressure values ​​of two adjacent data points; Multiple groups of segmentation points are set on the waveform curve, the number of segmentation points in different groups is different, and the time intervals between adjacent segmentation points in the group are the same; The number of feature points in each group of segmentation points is obtained, and the group whose number of feature points exceeds a preset threshold and has the least number of segmentation points is selected as the segmentation point.

[0012] Optionally, the real-time rotation speed sequence is constructed based on the diastolic pressure rotation speed, the systolic pressure rotation speed and a preset standard blood pressure value sequence, including: Construct a real-time speed sequence as follows : in, is a preset standard blood pressure value sequence, , s is the number of sequence points in the standard blood pressure value sequence, and the elements in the sequence are blood pressure values; Diastolic speed; is the systolic pressure speed; is the maximum value in the standard blood pressure value sequence; is the minimum value in the standard blood pressure value sequence; It is a real-time speed sequence, and the elements in the sequence are speeds.

[0013] Optionally, controlling the centrifugal pump to adjust the speed according to the real-time speed sequence includes: The moment when the centrifugal pump changes speed when simulating a heartbeat is obtained using the following modulo formula: Wherein, t is the current running time of the centrifugal pump; T is the interval time of the centrifugal pump changing the speed; s is the number of sequence points in the standard blood pressure value sequence; S is the total number of sequence points contained per minute; F is the preset heart rate; During the operation of the centrifugal pump, the remainder of the current operation time t of the centrifugal pump to the speed change interval T is continuously calculated, and each moment corresponding to the remainder being 0 is used as the moment when the centrifugal pump changes its speed. ; will be s Moments as a cycle, The moments correspond one-to-one to the elements in the real-time speed sequence, where the first The moment corresponds to the first element in the real-time speed sequence, and so on, until the sth After the last element in the real-time speed sequence corresponds to the moment, the next cycle The time corresponds to the real-time speed sequence; Control centrifugal pumps at each Always adjust to the corresponding speed.

[0014] The heartbeat simulation method according to claim 1 is characterized in that a pressure sensor is provided at the outlet of the centrifugal pump, and the pressure value of the blood pumped out by the centrifugal pump is obtained according to the output data of the pressure sensor.

[0015] Another aspect of the present invention provides a heartbeat simulation system for organ perfusion, which is applied to an organ perfusion device provided with a centrifugal pump, and the system comprises: a diastolic pressure speed determination module, configured to, after receiving a pressure adjustment instruction input by a user, use a PID control algorithm to adjust the speed of the centrifugal pump according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and use the current speed of the centrifugal pump as the diastolic pressure speed; a systolic pressure speed determination module, configured to adjust the speed of the centrifugal pump using a PID control algorithm based on the systolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the systolic pressure value, and use the current speed of the centrifugal pump as the systolic pressure speed; A real-time rotation speed sequence building module is configured to build a real-time rotation speed sequence based on the diastolic pressure rotation speed, the systolic pressure rotation speed and a preset standard blood pressure value sequence; The speed adjustment module is configured to control the centrifugal pump to adjust the speed according to the real-time speed sequence.

[0016] The present invention discloses a heartbeat simulation method and system for organ perfusion, which calculates the rotation speed corresponding to the diastolic pressure and systolic pressure set by the user through a PID control algorithm, and derives a real-time rotation speed sequence based on a standard blood pressure value sequence, thereby being able to accurately simulate the heartbeat process.

[0017] At the same time, the method and system disclosed in the present invention only need to adjust the PID control algorithm twice when the user sets the diastolic pressure and the systolic pressure, and run with reference to the real-time speed sequence during the subsequent working time. This can ensure that when there is no one to watch over the device, when the pressure changes due to blood vessel obstruction or rupture, the organ perfusion device will not adjust the speed according to the current pressure feedback, thereby avoiding secondary damage to the blood vessels caused by PID speed overshoot.

[0018] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the disclosure, nor is it intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other objects, features and advantages of the present disclosure will become more apparent through a more detailed description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present disclosure.

[0020] Figure 1 A schematic flow chart of a heartbeat simulation method for organ perfusion provided by an embodiment of the present invention; Figure 2 A schematic flow chart of another heartbeat simulation method for organ perfusion provided by an embodiment of the present invention; Figure 3 An implementation provided for an embodiment of the present invention Figure 1 Schematic diagram of the process of step S100; Figure 4 An implementation provided for an embodiment of the present invention Figure 1 Schematic diagram of the process of step S200; Figure 5 A schematic flow chart of another heartbeat simulation method for organ perfusion provided by an embodiment of the present invention; Figure 6 An implementation provided for an embodiment of the present invention Figure 5 Schematic diagram of the process of step S033; Figure 7 A schematic diagram of an organ perfusion device with a heartbeat simulation system provided by an embodiment of the present invention; Figure 8 A schematic diagram of the overall process of a heartbeat simulation method for organ perfusion provided by an embodiment of the present invention; Fig. 9 A schematic diagram of the structure of a heartbeat simulation system for organ perfusion provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0021] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0022] As used herein, the term "including" and its variations mean open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "or" means "and / or". The term "based on" means "based at least in part on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0023] Figure 1 A schematic flow chart of a heartbeat simulation method for organ perfusion provided in an embodiment of the present invention is applied to an organ perfusion device provided with a centrifugal pump, wherein the centrifugal pump can drive liquid (eg, blood) to be perfused into the organ. Figure 1 As shown, the method comprises the following steps: Step S100: After receiving the pressure adjustment instruction input by the user, the speed of the centrifugal pump is adjusted using a PID control algorithm according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and the current speed of the centrifugal pump is used as the diastolic pressure speed.

[0024] In one embodiment disclosed in the present invention, before executing step S100, Figure 2 As shown, the following steps are required: Step S011: determining whether a pressure adjustment instruction input by a user is received.

[0025] When the user needs to adjust the blood pressure value perfused into the organ, the user inputs a pressure adjustment instruction, which includes the desired diastolic and systolic pressure values ​​to be adjusted, wherein the diastolic pressure is the lowest pressure in the artery during cardiac diastole, for example, 80 mmHg; the systolic pressure is the highest pressure in the artery during cardiac contraction, for example, 120 mmHg.

[0026] If a pressure adjustment instruction input by the user is received, step S012 is executed: the diastolic pressure value and the systolic pressure value in the pressure adjustment instruction are obtained.

[0027] If no pressure adjustment instruction input by the user is received, step S013 is executed.

[0028] Step S013: Control the centrifugal pump to adjust the speed according to the current real-time speed sequence.

[0029] During a heartbeat, the blood pressure value is constantly changing. Therefore, in the embodiment disclosed in the present invention, different blood pressure values ​​in multiple time segments of a single heartbeat are simulated by using multiple centrifugal pump speeds arranged in sequence in a real-time speed sequence. After completing a heartbeat simulation, the heartbeat simulation continues to be performed according to the same real-time speed sequence to improve the preservation quality of the organ through periodic changes in blood flow pressure.

[0030] The real-time speed sequence will be described in detail in subsequent embodiments and will not be elaborated here.

[0031] In one embodiment disclosed in the present invention, Figure 3 As shown, the following sub-steps are used to implement step S100: Step S101: comparing the pressure value of the blood currently pumped out by the centrifugal pump with the diastolic pressure value in the pressure adjustment instruction, and adjusting the rotation speed of the centrifugal pump using a PID control algorithm according to the comparison result.

[0032] The PID control algorithm is based on a combination of proportional (P), integral (I) and differential (D). It adjusts the input of the centrifugal pump motor driver to achieve closed-loop control through real-time feedback of the error between the actual speed and the set value.

[0033] First, obtain the pressure value of the blood currently pumped out by the centrifugal pump and the current speed of the centrifugal pump, and compare the current pressure value with the diastolic pressure value in the pressure adjustment instruction. If the current pressure value is large, set a speed smaller than the current speed of the centrifugal pump for the PID control algorithm to reduce the current pressure value; if the current pressure value is small, set a speed larger than the current speed of the centrifugal pump for the PID control algorithm to increase the current pressure value.

[0034] Then, set the control parameters of the PID control algorithm , and .

[0035] Monitor the actual speed of the centrifugal pump and calculate the error between the actual speed and the set speed. Use the PID formula output to adjust the PWM duty cycle to adjust the voltage of the drive motor, thereby changing the speed of the centrifugal pump.

[0036] Step S102: continuously monitor the pressure value of the blood pumped out by the centrifugal pump, and use the centrifugal pump speed corresponding to the pressure value equal to the diastolic pressure value in the pressure adjustment instruction as the diastolic pressure speed.

[0037] After the speed of the centrifugal pump is adjusted by the PID control algorithm, the real-time pressure value of the blood pumped by the centrifugal pump is monitored. If the real-time pressure value is still less than or greater than the diastolic pressure value, the speed of the centrifugal pump is adjusted in step S101 until the real-time pressure value is equal to the diastolic pressure value in the pressure adjustment instruction. The speed of the centrifugal pump at this time is taken as the diastolic pressure speed, which means that when the centrifugal pump runs at the diastolic pressure speed, the pressure value of the blood pumped is the diastolic pressure value set by the user.

[0038] Step S200: Based on the systolic pressure value in the pressure adjustment instruction, the rotation speed of the centrifugal pump is adjusted using a PID control algorithm until the pressure value of the blood pumped out by the centrifugal pump is equal to the systolic pressure value, and the current rotation speed of the centrifugal pump is used as the systolic pressure rotation speed.

[0039] In one embodiment disclosed in the present invention, after determining the diastolic pressure speed, as Figure 4 As shown, the following sub-steps are used to implement step S200: Step S201: Compare the pressure value of the blood currently pumped out by the centrifugal pump with the systolic pressure value in the pressure adjustment instruction, and adjust the rotation speed of the centrifugal pump using a PID control algorithm according to the comparison result.

[0040] In a manner similar to step S101, the pressure value of the blood currently pumped out by the centrifugal pump is compared with the systolic pressure value in the pressure adjustment instruction, and the rotation speed of the centrifugal pump is adjusted by using a PID control algorithm.

[0041] Step S202: continuously monitor the pressure value of the blood pumped out by the centrifugal pump, and when the pressure value is equal to the systolic pressure value in the pressure adjustment instruction, the corresponding centrifugal pump speed is used as the systolic pressure speed.

[0042] In a manner similar to step S102, the pressure value of the blood pumped out by the centrifugal pump is continuously compared with the systolic pressure value until the real-time pressure value is equal to the systolic pressure value set by the user, and the rotation speed of the centrifugal pump at this time is used as the systolic pressure rotation speed.

[0043] Step S300: constructing a real-time rotation speed sequence based on the diastolic pressure rotation speed, the systolic pressure rotation speed and a preset standard blood pressure value sequence.

[0044] In one embodiment disclosed in the present invention, before executing step S300, Figure 5 As shown, the following steps are required: Step S031: Obtaining an arterial blood pressure waveform curve of a single heartbeat of a healthy population.

[0045] Obtain multiple arterial blood pressure waveform graphs of healthy people, and draw the arterial blood pressure waveform curve of a single heartbeat using a point drawing method or other methods.

[0046] Step S032: Delete the portion of the waveform curve where the blood pressure value is less than a preset lower limit.

[0047] The lowest point of the arterial blood pressure waveform is preset, for example, 60 mmHg, and the portion of the waveform curve that is less than 60 mmHg is deleted.

[0048] Step S033: selecting a preset number of segmentation points on the remaining waveform curves at the same time interval.

[0049] In one embodiment disclosed in the present invention, Figure 6 As shown, step S033 is implemented in the following manner: Step S0331: digitize the remaining waveform curve to obtain discrete data points, each of which corresponds to a blood pressure value.

[0050] After the remaining waveform curve is digitized, discrete data points with time and blood pressure value characteristics are obtained.

[0051] Step S0332: Use a preset point mapping method to obtain feature points from all data points.

[0052] The feature points are selected using a preset point drawing method. The blood pressure value corresponding to the feature point is greater than the blood pressure values ​​of the two adjacent data points, or the blood pressure value corresponding to the feature point is less than the blood pressure values ​​of the two adjacent data points. That is, the feature point is a peak point or a valley point in the small area where it is located. A waveform curve can be expressed by connecting the feature points.

[0053] Step S0333: setting a plurality of groups of segmentation points on the waveform curve, wherein the number of segmentation points in different groups is different and the time intervals between adjacent segmentation points in a group are the same.

[0054] For example, 6 groups of segmentation points are set, namely, 30 segmentation points in group A, 25 segmentation points in group B, 20 segmentation points in group C, 15 segmentation points in group D, 10 segmentation points in group E, and 5 segmentation points in group F. Each group of segmentation points can evenly segment the waveform curve in the time dimension, that is, the time intervals between adjacent segmentation points in the same group are the same.

[0055] Step S0334: Obtain the number of feature points in each group of segmentation points, and select the group with the least number of segmentation points and the number of feature points exceeding a preset threshold as the selected segmentation point.

[0056] For the segmentation points of groups A to F, it is checked whether there are feature points obtained in step S0332 in the segmentation points. If yes, the number of segmentation points that are feature points is counted.

[0057] After obtaining the number of feature points in each group of segmentation points, the groups whose number of feature points exceeds a preset threshold (eg, 6) are compared, and the group with the least number of segmentation points is selected.

[0058] For example, group A has 8 feature points, group B has 7 feature points, group C has 6 feature points, group D has 6 feature points, group E has 6 feature points, and group F has 4 feature points. Among the AE groups exceeding the preset threshold, the number of segmentation points of group E is 10, which is less than that of the other groups, so the segmentation points of group E are selected as the required segmentation points.

[0059] In another embodiment disclosed by the present invention, the number of segmentation points input by the user may also be used.

[0060] After the segmentation point is selected, continue to execute step S034.

[0061] Step S034: All segmentation points and the starting point and the ending point of the waveform curve are taken as sequence points.

[0062] The segmentation points (for example, 10) divide the waveform curve according to the same time interval, which means that the intermediate process of a single heartbeat is divided into 11 equal time parts. The starting point, the end point and all the segmentation points of the waveform curve represent the complete process of a single heartbeat. In the embodiment disclosed in the present invention, these points are used as sequence points, and the corresponding centrifugal pump speed is set for each sequence point in the subsequent embodiments.

[0063] Step S035: Constructing a standard blood pressure value sequence based on the blood pressure value corresponding to each sequence point in order from the starting point to the ending point.

[0064] For example, there are 12 sequence points, of which the starting point is in the order of 1, the first split point is in the order of 2, and so on, the ending point is in the order of 12. Each sequence point is sorted in descending order, and a standard blood pressure value sequence is constructed based on the blood pressure value corresponding to each sequence point, and the elements in the sequence are blood pressure values ​​arranged in order.

[0065] After the standard blood pressure value sequence is obtained, step S300 is executed to construct a real-time rotation speed sequence based on the diastolic pressure rotation speed, the systolic pressure rotation speed and the preset standard blood pressure value sequence.

[0066] In one embodiment disclosed in the present invention, step S300 is implemented in the following manner: Construct a real-time speed sequence as follows : in, is a preset standard blood pressure value sequence, , s is the number of sequence points in the standard blood pressure value sequence, and the elements in the sequence are blood pressure values; Diastolic speed; is the systolic speed; is the maximum value in the standard blood pressure value sequence; is the minimum value in the standard blood pressure value sequence; It is a real-time speed sequence, and the elements in the sequence are speeds.

[0067] The real-time speed sequence corresponds to the elements in the standard blood pressure value sequence one by one, and the time intervals between sequence elements are also the same. The constructed real-time speed sequence can indicate the change in the centrifugal pump speed at fixed intervals (i.e., the time interval between sequence points) during the simulation of a single heartbeat. Step S400: Control the centrifugal pump to adjust the speed according to the real-time speed sequence.

[0068] In one embodiment disclosed in the present invention, step S400 is implemented in the following manner: The moment when the centrifugal pump changes speed when simulating a heartbeat is obtained using the following modulo formula: Among them, t is the current running time of the centrifugal pump; T is the interval time for the centrifugal pump to change the speed, which is the same as the time interval between sequence points; s is the number of sequence points in the standard blood pressure value sequence; S is the total number of sequence points contained per minute; F is the pre-set heart rate.

[0069] During the operation of the centrifugal pump, the remainder of the current operation time t of the centrifugal pump to the speed change interval T is continuously calculated, and each moment corresponding to the remainder being 0 is used as the moment when the centrifugal pump changes its speed. .

[0070] will be s Moments as a cycle, The moments correspond one-to-one to the elements in the real-time speed sequence, where the first The moment corresponds to the first element in the real-time speed sequence, and so on, until the sth After the last element in the real-time speed sequence corresponds to the moment, the next cycle The time corresponds to the real-time speed sequence.

[0071] Control centrifugal pumps at each Always adjust to the corresponding speed.

[0072] For example, when a centrifugal pump starts running, t=0. When the running time t reaches T, The current moment t=T is the moment when the centrifugal pump changes its speed ,Should As the first element in the cycle, corresponding to the first element in the real-time speed sequence, the centrifugal pump is controlled to run at the speed of the first element in the real-time speed sequence at this moment.

[0073] The centrifugal pump continues to run. When the running time t reaches 2T, , the current moment t=2T is the moment when the centrifugal pump changes its speed ,Should As the second element in the cycle, corresponding to the second element in the real-time speed sequence, the centrifugal pump is controlled to run at the speed of the second element in the real-time speed sequence at this moment; and so on, until the running time t of the centrifugal pump reaches sT, the centrifugal pump is controlled to run at the speed of the last element in the real-time speed sequence at this moment.

[0074] The centrifugal pump continues to run. When the running time t reaches (s+1)T, , the current moment As the first element of the next cycle, it corresponds to the first element in the real-time speed sequence again. At all times, the centrifugal pump is controlled to run at the corresponding speed in the real-time speed sequence until the user inputs a pressure adjustment instruction again, and the method disclosed in the above embodiment is used to update the real-time speed sequence, and the centrifugal pump runs according to the updated real-time speed sequence.

[0075] In the embodiment disclosed in the present invention, a pressure sensor is provided at the outlet of the centrifugal pump, and the pressure value of the blood pumped out by the centrifugal pump can be obtained according to the output data of the pressure sensor.

[0076] For ease of understanding, the following diagram illustrates the entire heartbeat simulation method: like Figure 7 As shown, the organ perfusion equipment includes an organ bin, a blood storage tank, a centrifugal pump, and also includes a pressure sensor and a heartbeat simulation system proposed in an embodiment of the present invention (please refer to subsequent embodiments). The pressure sensor monitors the pressure value of the blood pumped out by the centrifugal pump in real time and feeds back to the heartbeat simulation system. The system controls the speed of the centrifugal pump according to the real-time pressure value.

[0077] Figure 8 The overall process of the heartbeat simulation method is shown. After the heartbeat simulation starts, the system first runs in the working mode and continues to determine whether the pressure instruction (i.e., the pressure adjustment instruction) sent by the user is received. If not, it continues to determine whether the current moment is the moment to change the speed. If so, the speed of the centrifugal pump is changed according to the current real-time speed sequence. If it is not the moment to change the speed, the centrifugal pump maintains the current speed and waits for the running time to reach the moment to change the speed.

[0078] If a pressure adjustment instruction is received from the user, the system will run in pressure mode. First, it will determine whether the current pressure value is equal to the diastolic pressure value in the pressure adjustment instruction. If so, the current speed of the centrifugal pump will be used as the diastolic pressure speed (min_w). If not, the PID control algorithm will be used to adjust the speed of the centrifugal pump until the current pressure is equal to the diastolic pressure value. Then, it will be determined whether the current pressure is equal to the systolic pressure value in the pressure adjustment instruction. If so, the current speed of the centrifugal pump will be used as the systolic pressure speed (max_w). If not, the PID control algorithm will be used to adjust the speed of the centrifugal pump until the current pressure is equal to the systolic pressure value. The real-time speed sequence is obtained using the diastolic pressure speed and the systolic pressure speed, and then the real-time speed sequence is provided to the working mode as a reference for the speed of the centrifugal pump during the heartbeat simulation process.

[0079] Fig. 9 A heartbeat simulation system for organ perfusion provided by an embodiment of the present invention is applied to an organ perfusion device provided with a centrifugal pump, such as Fig. 9 As shown, the system includes the following modules: The diastolic pressure speed determination module 1 is configured to, after receiving the pressure adjustment instruction input by the user, adjust the speed of the centrifugal pump using a PID control algorithm according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and use the current speed of the centrifugal pump as the diastolic pressure speed; The systolic pressure speed determination module 2 is configured to adjust the speed of the centrifugal pump using a PID control algorithm based on the systolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the systolic pressure value, and use the current speed of the centrifugal pump as the systolic pressure speed; A real-time speed sequence building module 3 is configured to build a real-time speed sequence based on the diastolic pressure speed, the systolic pressure speed and a preset standard blood pressure value sequence; The speed adjustment module 4 is configured to control the centrifugal pump to adjust the speed according to the real-time speed sequence.

[0080] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A heartbeat simulation method for organ perfusion, applied to an organ perfusion device provided with a centrifugal pump, characterized in that: The method comprises: After receiving the pressure adjustment instruction input by the user, the speed of the centrifugal pump is adjusted using a PID control algorithm according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and the current speed of the centrifugal pump is used as the diastolic pressure speed; Based on the systolic pressure value in the pressure adjustment instruction, the rotation speed of the centrifugal pump is adjusted by using a PID control algorithm until the pressure value of the blood pumped out by the centrifugal pump is equal to the systolic pressure value, and the current rotation speed of the centrifugal pump is used as the systolic pressure rotation speed; Construct a real-time speed sequence based on the diastolic speed, systolic speed and a preset standard blood pressure value sequence; Control the centrifugal pump to adjust the speed according to the real-time speed sequence.

2. The heartbeat simulation method according to claim 1, characterized in that: Before executing the step of, after receiving the pressure adjustment instruction input by the user, adjusting the rotation speed of the centrifugal pump by using a PID control algorithm according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and using the current rotation speed of the centrifugal pump as the diastolic pressure rotation speed, the method further includes: Determine whether a pressure adjustment instruction input by the user is received, If yes, obtain the diastolic pressure value and the systolic pressure value in the pressure adjustment instruction; If not, the centrifugal pump is controlled to adjust the speed according to the current real-time speed sequence.

3. The heartbeat simulation method according to claim 1 or 2, characterized in that: After receiving the pressure adjustment instruction input by the user, the rotation speed of the centrifugal pump is adjusted by using a PID control algorithm according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and the current rotation speed of the centrifugal pump is used as the diastolic pressure rotation speed, including: Compare the pressure value of the blood currently pumped out by the centrifugal pump with the diastolic pressure value in the pressure adjustment instruction, and adjust the speed of the centrifugal pump using a PID control algorithm according to the comparison result; The pressure value of the blood pumped out by the centrifugal pump is continuously monitored, and the speed of the centrifugal pump corresponding to the pressure value being equal to the diastolic pressure value in the pressure adjustment instruction is used as the diastolic pressure speed.

4. The heartbeat simulation method according to claim 3, characterized in that: The method of adjusting the rotation speed of the centrifugal pump by using a PID control algorithm based on the systolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped out by the centrifugal pump is equal to the systolic pressure value, and using the current rotation speed of the centrifugal pump as the systolic pressure rotation speed includes: Compare the pressure value of the blood currently pumped out by the centrifugal pump with the systolic pressure value in the pressure adjustment instruction, and adjust the speed of the centrifugal pump using a PID control algorithm according to the comparison result; The pressure value of the blood pumped out by the centrifugal pump is continuously monitored, and the corresponding centrifugal pump speed when the pressure value is equal to the systolic pressure value in the pressure adjustment instruction is used as the systolic pressure speed.

5. The heartbeat simulation method according to claim 1, characterized in that: Before executing the step of constructing a real-time rotation speed sequence based on the diastolic pressure rotation speed, the systolic pressure rotation speed and a preset standard blood pressure value sequence, the method further includes: Obtain the arterial blood pressure waveform curve of a single heartbeat in healthy people; Deleting the portion of the waveform curve where the blood pressure value is less than a preset lower limit; Selecting a preset number of segmentation points on the remaining waveform curves at the same time interval; All segmentation points and the start and end points of the waveform curve are regarded as sequence points; In order from the starting point to the ending point, a standard blood pressure value sequence is constructed based on the blood pressure value corresponding to each sequence point.

6. The heartbeat simulation method according to claim 5, characterized in that: The step of selecting a preset number of segmentation points on the remaining waveform curve at the same time interval includes: The remaining waveform curve is digitized to obtain discrete data points, each of which corresponds to a blood pressure value; A preset point plotting method is used to obtain a characteristic point from all data points, wherein the blood pressure value corresponding to the characteristic point is greater than the blood pressure values ​​of two adjacent data points, or the blood pressure value corresponding to the characteristic point is less than the blood pressure values ​​of two adjacent data points; Multiple groups of segmentation points are set on the waveform curve, the number of segmentation points in different groups is different, and the time intervals between adjacent segmentation points in the group are the same; The number of feature points in each group of segmentation points is obtained, and the group whose number of feature points exceeds a preset threshold and has the least number of segmentation points is selected as the segmentation point.

7. The heartbeat simulation method according to claim 1, characterized in that: The real-time speed sequence is constructed based on the diastolic pressure speed, the systolic pressure speed and a preset standard blood pressure value sequence, including: Construct a real-time speed sequence as follows : in, is a preset standard blood pressure value sequence, , s is the number of sequence points in the standard blood pressure value sequence, and the elements in the sequence are blood pressure values; Diastolic speed; is the systolic pressure speed; is the maximum value in the standard blood pressure value sequence; is the minimum value in the standard blood pressure value sequence; It is a real-time speed sequence, and the elements in the sequence are speeds.

8. The heartbeat simulation method according to claim 6, characterized in that: The controlling the centrifugal pump to adjust the speed according to the real-time speed sequence comprises: The moment when the centrifugal pump changes speed when simulating a heartbeat is obtained using the following modulo formula: Wherein, t is the current running time of the centrifugal pump; T is the interval time of the centrifugal pump changing the speed; s is the number of sequence points in the standard blood pressure value sequence; S is the total number of sequence points contained per minute; F is the preset heart rate; During the operation of the centrifugal pump, the remainder of the current operation time t of the centrifugal pump to the speed change interval T is continuously calculated, and each moment corresponding to the remainder being 0 is used as the moment when the centrifugal pump changes its speed. ; will be s Moments as a cycle, The moments correspond one-to-one to the elements in the real-time speed sequence, where the first The moment corresponds to the first element in the real-time speed sequence, and so on, until the sth After the last element in the real-time speed sequence corresponds to the moment, the next cycle The time corresponds to the real-time speed sequence; Control centrifugal pumps at each Always adjust to the corresponding speed.

9. The heartbeat simulation method according to claim 1, characterized in that: A pressure sensor is provided at the outlet of the centrifugal pump, and the pressure value of the blood pumped out by the centrifugal pump is obtained according to the output data of the pressure sensor.

10. A heartbeat simulation system for organ perfusion, applied to an organ perfusion device provided with a centrifugal pump, characterized in that: The system comprises: a diastolic pressure speed determination module, configured to, after receiving a pressure adjustment instruction input by a user, use a PID control algorithm to adjust the speed of the centrifugal pump according to the diastolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the diastolic pressure value, and use the current speed of the centrifugal pump as the diastolic pressure speed; a systolic pressure speed determination module, configured to adjust the speed of the centrifugal pump using a PID control algorithm based on the systolic pressure value in the pressure adjustment instruction until the pressure value of the blood pumped by the centrifugal pump is equal to the systolic pressure value, and use the current speed of the centrifugal pump as the systolic pressure speed; A real-time rotation speed sequence building module is configured to build a real-time rotation speed sequence based on the diastolic pressure rotation speed, the systolic pressure rotation speed and a preset standard blood pressure value sequence; The speed adjustment module is configured to control the centrifugal pump to adjust the speed according to the real-time speed sequence.

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