Pressure self-adaption method and device

Abstract

The invention provides a pressure self-adaption method and device.The method comprises the steps that after a flushing device is connected with a ventricular assist device, first pressure is obtained, and the first pressure is flushing pipeline pressure when a pump assembly drives flushing fluid at the first flushing fluid flow speed; calculating a target flushing fluid flow rate flowing into the flushing pipeline according to the first pressure; target pressure is calculated according to the target flushing fluid flow velocity, so that outlet pressure of the flushing pipeline is larger than second pressure, and the second pressure is environment pressure of the flushing pipeline. The appropriate flushing fluid flow velocity is calculated according to the currently detected flushing pipeline pressure, and then the optimal flushing pipeline pressure is calculated according to the flushing fluid flow velocity, so that the pressure of the flushing fluid output by the flushing pipeline is larger than the environment pressure in real time, and a pressure barrier between blood and a motor in the ventricular assist device is kept in a stable state; and safe operation of the ventricular auxiliary device is ensured.

Description

Technical Field

[0001] The present application relates to the field of medical device technology, and in particular to a pressure adaptive method and device. Background Art

[0002] The ventricular assist system mainly includes an interventional ventricular assist device, a controller and a flushing device. The interventional ventricular assist device (VAD) is mainly used for protection in high-risk percutaneous coronary intervention (PCI) surgery. The flushing device is used to maintain the pressure barrier between the blood and the motor. It uses the pressure formed by the flushing fluid in the opposite direction of blood flow to isolate the blood from the motor and prevent blood from entering the motor. However, current flushing devices generally directly set a fixed pressure and maintain the flushing device at the fixed pressure. However, when the blood pressure in the ventricular assist device changes, the flushing device cannot be adjusted in time, affecting the operation of the ventricular assist device. Summary of the invention

[0003] The embodiments of the present application provide a pressure adaptive method and device, which can adaptively control the pressure in the flushing circuit according to the ambient pressure, so that the pressure barrier between the blood and the motor in the ventricular assist device remains in a stable state, thereby ensuring the safe operation of the ventricular assist device.

[0004] In a first aspect, an embodiment of the present application provides a pressure adaptation method, the method comprising:

[0005] After the flushing device and the ventricular assist device are in operation, obtaining a first pressure, the first pressure being the flushing line pressure when the pump assembly drives the flushing fluid at a first flushing fluid flow rate;

[0006] calculating a target flushing liquid flow rate flowing into the flushing pipeline according to the first pressure;

[0007] The target pressure is calculated according to the target flushing liquid flow rate so that the outlet pressure of the flushing pipeline is greater than a second pressure, where the second pressure is the ambient pressure of the flushing pipeline.

[0008] In a second aspect, an embodiment of the present application provides a control circuit of a flushing device, wherein the flushing device includes a flushing pipeline for conveying a flushing liquid and a pump assembly for driving the flushing liquid to flow, and the control circuit includes one or more processors, wherein the one or more processors are used to:

[0009] After the flushing device and the ventricular assist device are in operation, obtaining a first pressure, the first pressure being the flushing line pressure when the pump assembly drives the flushing fluid at a first flushing fluid flow rate;

[0010] calculating a target flushing liquid flow rate flowing into the flushing pipeline according to the first pressure;

[0011] The target pressure is calculated according to the target flushing liquid flow rate so that the outlet pressure of the flushing pipeline is greater than a second pressure, where the second pressure is the ambient pressure of the flushing pipeline.

[0012] In a third aspect, an embodiment of the present application provides a ventricular assist system, the ventricular assist system comprising:

[0013] ventricular assist device;

[0014] a flushing device for providing flushing fluid to the ventricular assist device, the flushing device comprising a flushing pipeline for conveying the flushing fluid and a pump assembly for driving the flushing fluid to flow;

[0015] A control circuit for controlling the operation of the ventricular assist device and the pump assembly, wherein the control circuit is used to execute the steps in the method described in the first aspect above.

[0016] In a fourth aspect, an embodiment of the present application provides a medical device, comprising a processor, a memory, a communication interface, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the processor, and the program includes instructions for executing some or all of the steps described in the method described in the first aspect above.

[0017] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program for electronic data exchange, wherein the computer program enables a computer to execute some or all of the steps described in the method described in the first aspect above.

[0018] In a sixth aspect, an embodiment of the present application provides a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, and the computer program is operable to cause a computer to execute some or all of the steps described in the method described in the first aspect of the embodiment of the present application. The computer program product may be a software installation package.

[0019] The technical solution provided by the present application is to obtain a first pressure after the flushing device is connected to the ventricular assist device, the first pressure being the flushing line pressure when the pump assembly drives the flushing liquid at a first flushing liquid flow rate; calculate the target flushing liquid flow rate flowing into the flushing line according to the first pressure; calculate the target pressure according to the target flushing liquid flow rate, so that the outlet pressure of the flushing line is greater than the second pressure, the second pressure being the environmental pressure of the flushing line. The present application calculates a suitable flushing liquid flow rate according to the currently detected flushing line pressure, and then calculates the optimal flushing line pressure according to the flushing liquid flow rate, so that the flushing liquid pressure output by the flushing line is greater than its environmental pressure in real time, so that the pressure barrier between the blood and the motor in the ventricular assist device remains in a stable state, thereby ensuring the safe operation of the ventricular assist device. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 is a schematic diagram of a ventricular assist system provided in an embodiment of the present application;

[0022] Figure 2 It is a structural schematic diagram of a flushing device provided in an embodiment of the present application when the pump door is closed;

[0023] Figure 3 It is a schematic diagram of the structure of a flushing device provided in an embodiment of the present application when the pump door is omitted;

[0024] Figure 4 It is a structural schematic diagram of a flushing pipeline and a pump door provided in an embodiment of the present application;

[0025] Figure 5 is a flow chart of a pressure adaptation method provided in an embodiment of the present application;

[0026] Figure 6 It is a structural schematic diagram of a medical device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to help those skilled in the art better understand the technical solutions of the present application, the following is a clear and complete description of the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the description of the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0028] The terms "first", "second", etc. in the specification and claims of this application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, software, product, or device that includes a series of steps or units is not limited to the listed steps or units, but also includes steps or units that are not listed, or also includes other steps or units inherent to these processes, methods, products, or devices.

[0029] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0030] The medical equipment and pump involved in the present application may be a ventricular assist device (VAD), such as an implantable ventricular assist device, an interventional ventricular assist device, etc.; the ventricular assist device may include at least one blood pump, wherein the blood pump may be a centrifugal pump, an axial flow pump, a magnetic levitation pump, etc.

[0031] It should be noted that, in the present application, the term "proximal end" or "proximal side" refers to the end or side closer to the surgical operator; and the term "distal end" or "distal side" refers to the end or side farther from the surgical operator.

[0032] In this application, if Figure 1 As shown, the ventricular assist system includes a ventricular assist device 30, an external controller 10 and a flushing fluid device 10. The ventricular assist device 30 is implanted in the patient's body, crossing the aortic valve of the patient's heart, so that the proximal end of the ventricular assist device 30 is located in the aorta and the distal end of the ventricular assist device 30 is located in the left ventricle, so that the blood in the left ventricle is pumped into the aorta through the ventricular assist device 30 to provide partial or complete assistance to the cardiac circulatory system. The controller 20 and the flushing fluid device 10 are located outside the body, and the controller 20 is used to realize the control and data display of the ventricular assist device 30 and the flushing device 10, as well as the functions of fault detection alarm, data recording, etc. The flushing fluid device 10 is used to maintain a pressure barrier between the blood and the motor. By connecting the flushing pipeline of the flushing device 10 to the motor bearing in the ventricular assist device 30, the fluid pressure formed by the flushing fluid in the opposite direction of blood flow is used to isolate the blood from the motor to prevent blood from entering the motor.

[0033] like Figure 2-Figure 4 As shown, the flushing device 10 includes a base 200 and a pump door 120. The pump door 120 is movably connected to the base 200, for example, rotatably connected. The pump door 120 and the base 200 can be closed or opened by rotating the pump door 120 relative to the base 200.

[0034] A pump assembly and a flushing pipeline 400 are installed in the base 200. The flushing pipeline 400 is at least partially located between the pump assembly and the pump door 120. Specifically, the flushing pipeline 400 has a first pipe section 410, and the first pipe section 410 is located between the pump assembly and the pump door 120; when the pump door 120 covers the base 200, the pump door 120 and the pump assembly can jointly squeeze the first pipe section 410 in the flushing pipeline 400.

[0035] For example, the pump assembly includes a peristaltic unit 140, which is arranged on the base 200 and corresponds to the first pipe segment 410 of the flushing pipeline 400. The peristaltic unit 140 has a plurality of peristaltic sheets 141, and the plurality of peristaltic sheets 141 are arranged in sequence along the extension direction of the flushing pipeline 400. The peristaltic sheets 141 and the pump door 120 are distributed on two opposite sides of the radial direction of the flushing pipeline 400 (specifically the first pipe segment 410), and can act together on the flushing pipeline 400.

[0036] In one embodiment, the pump assembly further includes a rotating shaft, on which a plurality of cams are arranged, and the plurality of cams are sequentially driven and installed on the rotating shaft along the axial direction, and each cam is fitted with a peristaltic sheet 141, and the cams on the rotating shaft cause the peristaltic sheet 141 to produce a wave-like motion according to a certain timing, and each peristaltic sheet 141 can move back and forth along the radial direction of the flushing pipeline 400. When the peristaltic sheet 141 moves toward the direction close to the flushing pipeline 400, it can work together with the pump door 120 to squeeze the flushing pipeline 400, so that the fluid in the flushing pipeline 400 is subjected to a continuous thrust related to the movement timing of the peristaltic sheet 141, thereby causing the fluid to flow, and achieving the effect of conveying the fluid.

[0037] When the pump door 120 covers the base 200, the first pipe section 410 is located between the peristaltic unit 140 and the pump door 120. When the peristaltic unit 140 starts to work, the peristaltic unit 140 moves toward the pump door 120, thereby squeezing the flushing pipeline 400 together with the pump door 120, squeezing out the liquid in the flushing pipeline 400, and finally realizing the pumping function of the flushing device 10 on the liquid.

[0038] The flushing pipeline 400 further includes a second pipe section 420 in communication with the first pipe section 410. The flushing device 10 further includes a pressure sensor 130. The pressure sensor 130 is in contact with the second pipe section 420 in the flushing pipeline 400. In other words, the pressure sensor 130 is disposed on the outer wall of the flushing pipeline 400 (specifically, the second pipe section 420) to detect the pressure of the second pipe section 420. The second pipe section 420 is a section of the flushing pipeline 400 that is not squeezed by the pump door 120 and / or the peristaltic unit 140.

[0039] In one embodiment, the base 200 is provided with an installation channel 330 for the flushing pipeline 400 to pass through, and the pressure sensor 130 is at least partially located in the installation channel 330. The base 200 is provided with a cover plate 300, which covers a portion of the installation channel 330, and the second pipe section 420 is installed in the installation channel 330. The position of the second pipe section 420 corresponds to the position of the cover plate 300, and the position of the pressure sensor 130 also corresponds to the position of the cover plate 300, and the pressure sensor 130 is located between the cover plate 300 and the pressure sensor 130. When the flushing pipeline 400 is installed in the installation channel 330, the cover plate 300 makes the pressure sensor 130 contact with the second pipe section 420 in the flushing pipeline 400, so that the pressure sensor 130 can detect the pressure of the second pipe section 420.

[0040] For example, the flushing device 10 further includes a control circuit electrically connected to the peristaltic unit 140, and the control circuit can control the fluid pressure and fluid flow in the flushing pipeline 400 by controlling the running speed of the peristaltic unit 140. The faster the rotating shaft rotates, the faster the fluid delivery speed.

[0041] For example, the control circuit in the flushing device 10 can be integrated into the flushing device 10 (such as being disposed in the accommodating chamber 220), or can be integrated into the control device 20, which is not limited in the embodiments of the present application.

[0042] The ventricular assist device 30 has a sleeve, an impeller and a motor. The impeller is disposed in the sleeve. The motor shaft of the motor extends from an opening at the distal end of the motor housing and is connected to the impeller. The motor shaft rotates to drive the impeller to rotate. The motor shaft is supported by a bearing located in the motor housing. Usually, a radial bearing for supporting the motor shaft is disposed at the distal opening of the motor housing. However, since the motor of the interventional ventricular assist device 30 is disposed in the human body, blood will flow into the motor at the opening at the distal end of the motor housing from the gap between the motor shaft and the motor housing or the radial bearing at the distal end. A large amount of blood entering the motor will affect the normal operation of the motor, causing problems such as increased load and transmission failure. Therefore, in the interventional ventricular assist system, a flushing fluid is often used to prevent blood from entering the motor of the ventricular assist device 30. At the same time, the heat generated by the motor during operation can be discharged through the flushing fluid. One end of the flushing line 400 can be connected to an infusion bottle or an infusion bag, which can provide flushing fluids such as saline or heparin; the other end of the flushing line 400 can be accommodated in the catheter of the ventricular assist device 30, which is connected to the proximal end of the motor, so that the flushing line 400 is connected to the proximal end of the motor, and the distal end of the motor is connected to the sleeve. The flushing fluid entering the motor flows out from the distal end of the motor, so that the flow direction of the liquid transported by the flushing device 10 is opposite to the direction of blood pumping in the ventricular assist device 30, thereby achieving fluid sealing of the distal end of the motor of the ventricular assist device 30, preventing blood from entering the motor through the gap between the motor shaft and the motor housing or the radial bearing at the distal end, thereby causing motor failure.

[0043] To ensure the fluid sealing effect, the pressure at the outlet of the flushing line 400 needs to be continuously greater than or equal to the blood pressure to provide a reliable back pressure to the ventricular assist device 30 and ensure the safe operation of the ventricular assist device 30. However, for different users, the motor speed of the ventricular assist device 30 set by them will be different, and the user's own human blood pressure will also be different, so that the blood pressure pumped by the ventricular assist device 30 of each user is different, and the motor speed required in different scenarios (such as surgical scenarios, daily use scenarios) will be different, and the motor speed will also be adjusted according to the user's physical condition. Therefore, during the operation of the ventricular assist device 30, the blood pressure pumped by the ventricular assist device 30 will change, and this change will cause the pressure barrier formed between the flushing line pressure and the blood pressure to change, and the flushing line pressure set by the user may not be adjusted in time, and the flushing line pressure set too high may cause excessive anticoagulation due to the large flow of flushing fluid or affect the treatment of diabetic patients; while the flushing line pressure is too low, blood may enter the motor, increase the risk of thrombosis, and damage the motor.

[0044] In response to the above problems, the present application proposes a pressure adaptive method, which determines the ambient pressure of the flushing circuit in the ventricular assist device 30 according to the pressure-flow characteristic curve of the flushing circuit 400, and adaptively adjusts the flushing liquid flow and pressure according to the ambient pressure. While ensuring the fluid sealing effect of the flushing liquid, the optimal pressure of the flushing device 10 is automatically determined to ensure the pressure barrier between the blood and the motor in the ventricular assist device 30, avoid excessive or insufficient pressure in the flushing circuit, and ensure the safe operation of the ventricular assist device 30.

[0045] In combination with the above description, the present application is described below from the perspective of method examples.

[0046] See also Figure 5 , Figure 5 A schematic diagram of a pressure adaptation method provided in an embodiment of the present application is applied to Figure 1-Figure 4 The flushing device 10 shown. Figure 5 As shown, the method includes the following steps.

[0047] S510. After the flushing device and the ventricular assist device are in operation, a first pressure is obtained, where the first pressure is the flushing line pressure when the pump assembly drives the flushing fluid at a first flushing fluid flow rate.

[0048] After leaving the factory, the flushing circuit 400 of the flushing device 10 is connected to the motor in the ventricular assist device 30 to provide flushing fluid to the motor through the flushing device 10 to form a fluid seal at the distal end of the motor. After the ventricular assist device 30 is implanted in the patient's body, the ventricular assist device 30 and the flushing device 10 are started, wherein the ventricular assist device 30 can be operated at the set target speed, and the flushing device 10 can be operated at the preset default flushing fluid flow rate (i.e., the first flushing fluid flow rate). During the operation of the flushing device 10 at the first flushing fluid flow rate, the first pressure can be obtained by the pressure sensor 130 disposed in the flushing cavity. The first pressure is the flushing circuit pressure detected when the flushing fluid is input into the flushing circuit 400 at the first flushing fluid flow rate, that is, the pressure detected by the pressure sensor 130.

[0049] The flow rate of the flushing liquid is related to the movement speed of the pump assembly, wherein the faster the pump assembly rotates, the faster the flow rate of the flushing liquid will be. When the outflow rate of the flushing pipeline 400 remains unchanged and the pressure in the flushing pipeline 400 is kept balanced, when the flushing liquid inflow rate is increased by increasing the rotation speed of the pump assembly, the pressure in the flushing pipeline 400 will gradually increase, thereby increasing the fluid pressure of the flushing liquid flowing into the motor. Similarly, when the outflow rate of the flushing pipeline 400 remains unchanged and the pressure in the flushing pipeline 400 is kept balanced, when the flushing liquid inflow rate is reduced by reducing the rotation speed of the pump assembly, the pressure in the flushing pipeline 400 will gradually decrease, thereby also reducing the fluid pressure of the flushing liquid flowing into the motor.

[0050] The present application can first control the operation of the flushing device 10 at a default flushing fluid flow rate, and estimate the optimal flushing fluid flow rate and flushing pipeline pressure of the flushing device 10 at the current target rotation speed by detecting the flushing fluid flow rate, thereby improving the operating efficiency of the flushing device 10 while ensuring the safe operation of the ventricular assist device 30.

[0051] S520. Calculate a target flushing liquid flow rate flowing into the flushing pipeline according to the first pressure.

[0052] Among them, when the ventricular assist system is in operation, the pressure of the flushing liquid output by the flushing circuit 400 needs to be greater than the blood pressure in the ventricular assist device 30 (i.e., the blood pressure in the cannula of the ventricular assist device 30) in real time. In other words, the flushing circuit pressure depends on the blood pressure in the ventricular assist device 30. Therefore, the control circuit can estimate the current blood pressure in the ventricular assist device 30 (i.e., the ambient pressure of the flushing circuit 400) according to the first pressure, wherein the ambient pressure of the flushing circuit is the ambient pressure at one end of the flushing circuit 400 accommodated in the catheter of the ventricular assist device 30. The flushing circuit pressure is roughly estimated according to the blood pressure in the ventricular assist device 30, and then the flow rate of the flushing liquid flowing into the flushing circuit 400 is determined, so that the flushing circuit pressure can reach the flushing circuit pressure estimated by the rough cloth.

[0053] For example, calculating the target flushing liquid flow rate flowing into the flushing pipeline based on the first pressure includes: obtaining a first pressure curve, the first pressure curve being a curve of the relationship between the second pressure and the flushing pipeline pressure at the first flushing liquid flow rate; determining a third pressure corresponding to a preset pressure from the first pressure curve; and calculating the target flushing liquid flow rate based on the first pressure and the third pressure.

[0054] In the present application, before the ventricular assist system leaves the factory, the relationship curve between the ambient pressure of the flushing line 400 contained in the catheter of the ventricular assist device 30 and the flushing line pressure can be measured by placing the ventricular assist device 30 in a test environment and measuring different flushing liquid flow rates, and then the pressure curve at each flushing liquid flow rate is stored in the control circuit. When the ventricular assist device 30 and the flushing device 10 are in operation, the first pressure curve at the first flushing liquid flow rate is obtained from the control circuit, and then the flushing line pressure (i.e., the third pressure) when the ambient pressure of the flushing line 400 is 0 can be determined according to the first pressure curve. The third pressure is the flushing line pressure when the ambient pressure of the flushing line 400 is 0, that is, the flushing line pressure when there is no blood in the motor in the ventricular assist device 30.

[0055] Optionally, calculating the target flushing fluid flow rate based on the first pressure and the third pressure includes: obtaining a second pressure curve, the second pressure curve being a relationship curve between the flushing fluid flow rate and the flushing pipeline pressure when the flushing device is not connected to the ventricular assist device; determining the first pipeline pressure drop corresponding to the first flushing fluid flow rate according to the second pressure curve; calculating the second pressure according to the first pressure and the third pressure; obtaining a third pressure curve, the third pressure curve being a relationship curve between the flushing fluid flow rate and the flushing pipeline pressure under the second pressure; calculating an estimated pressure according to the first pipeline pressure drop and the second pressure; and determining the target flushing fluid flow rate corresponding to the estimated pressure from the third pressure curve.

[0056] The first pressure is the flushing line pressure under the environmental pressure of the flushing line 400. The characteristics of the polymer material of the flushing line 400 will cause a certain pressure loss in the flushing line 400 itself, that is, there is a certain difference between the pressure detected by the pressure sensor 130 and the pressure of the flushing liquid output by the flushing line 400, and the difference is determined by the characteristics of the flushing line itself. Therefore, by calculating the difference between the first pressure and the third pressure, the blood pressure (i.e., the second pressure) in the ventricular assist device 30 at the current speed can be determined. In other words, the difference between the first pressure and the third pressure is the second pressure.

[0057] In the present application, before the ventricular assist system leaves the factory, the ventricular assist device 30 can be placed in a test environment, and a second pressure curve between the flushing fluid flow rate in the flushing device 10 and the flushing line pressure can be measured when the flushing device 10 is not connected to the ventricular assist device 30, and then the second pressure curve can be stored in the control circuit. The second pressure curve can reflect the relationship between the pressure drop in the flushing line 400 and the flushing fluid flow rate. When the flushing device 10 is running, the control circuit can determine the line pressure drop corresponding to the current first flushing fluid flow rate from the second pressure curve. The first line pressure drop is the pressure loss in the flushing line 400 at the first flushing fluid flow rate.

[0058] In order to prevent the blood in the ventricular assist device 30 from entering its motor, the pressure of the flushing liquid output by the flushing pipeline 400 in the flushing device 10 needs to be greater than the blood pressure in the ventricular assist device 30 (or the blood pressure in the cannula). Considering the pipeline pressure drop of the flushing pipeline 400 itself, the required flushing pipeline pressure (i.e., estimated pressure) can be roughly estimated according to the second pressure and the first pipeline pressure drop. The estimated pressure is equal to the sum of the second pressure and the first pipeline pressure drop.

[0059] In the present application, before the ventricular assist system leaves the factory, the ventricular assist device 30 can be placed in a test environment, and the relationship curve between the flushing fluid flow rate in the flushing device 10 and the flushing line pressure can be measured under different environmental pressures of the flushing line 400, and then the pressure curve under each environmental pressure is stored in the control circuit. When the ventricular assist device 30 and the flushing device 10 are in operation, the control circuit obtains a third pressure curve corresponding to the second pressure from the multiple pressure curves, and determines the flushing fluid flow rate (i.e., the target flushing fluid flow rate) when the flushing line pressure reaches the estimated pressure according to the third pressure curve.

[0060] S530, calculating a target pressure according to the target flushing liquid flow rate, so that the outlet pressure of the flushing pipeline 400 is greater than a second pressure, where the second pressure is the ambient pressure of the flushing pipeline.

[0061] The estimated pressure is a rough estimate, and its deviation may be large. If the flushing line pressure is too high, a large amount of flushing fluid will enter the patient's body, resulting in excessive anticoagulation and affecting the patient's treatment; if the flushing line pressure is too low, it will not be able to form a fluid seal for the motor, causing blood to enter the motor and damage the motor. Therefore, after estimating the estimated pressure, the control circuit can further estimate the flushing line pressure according to the target flushing fluid flow rate to calculate a more accurate target pressure and achieve precise control of the flushing line pressure.

[0062] Wherein, the target pressure is within a preset pressure range, and the preset pressure range is 300 mmHg to 1100 mmHg. Due to its material properties, the pressure that the flushing pipeline can withstand is fixed. When the flushing pipeline pressure is greater than the maximum pressure it can withstand, the flushing pipeline 400 will rupture due to the excessive pressure. Therefore, during the operation of the flushing device 10, in order to ensure the service life of the flushing pipeline 400, the target pressure needs to be within a preset pressure range, which is the pressure range that the flushing pipeline 400 can withstand.

[0063] Optionally, calculating the target pressure according to the target flushing liquid flow rate includes: determining a second pipeline pressure drop corresponding to the target flushing liquid flow rate from the second pressure curve; substituting the second pipeline pressure drop and the second pressure into a target formula to calculate the target pressure, and the target formula is P=k(ΔP+P b ), ΔP is the pipeline pressure drop, and P b is the ambient pressure of the flushing pipeline, k is the adjustment coefficient, and k is greater than 1.

[0064] Since the pipeline pressure drop of the flushing pipeline 400 is different at different flushing liquid flow rates, after determining the target flushing liquid flow rate, the pipeline pressure drop can be further determined according to the target flushing liquid flow rate to reduce the deviation of the target pressure.

[0065] The control circuit determines the second pipeline pressure drop corresponding to the target flushing liquid flow rate from the second pressure curve, and then re-estimates the flushing pipeline pressure based on the second pipeline pressure drop and the second pressure. Specifically, the control circuit substitutes the second pipeline pressure drop and the second pressure into the target formula to calculate the target pressure. Since it is necessary to ensure that the flushing liquid pressure output by the flushing pipeline 400 is greater than the second pressure in real time, the sum of the second pipeline pressure drop and the second pressure is multiplied by k so that the flushing liquid forms a fluid seal in the motor, where k is greater than 1. For example, k is greater than or equal to 1.5, for example, k is 1.5, 1.7, 1.8, etc.

[0066] In the present application, the control circuit can automatically determine the maximum flushing line pressure of the flushing device 10 when the ventricular assist device 30 is currently operating at the target speed through a pre-measured pressure curve and a default flushing fluid flow rate, thereby reducing the impact of the flushing fluid on the patient while ensuring the safe operation of the ventricular assist device 30.

[0067] In one possible example, the method further includes: adjusting the flushing fluid flow rate to maintain the flushing circuit pressure at the target pressure; and recalculating the target pressure when the rotation speed of the ventricular assist device changes or the fluctuation value of the flushing circuit pressure exceeds a preset value.

[0068] After calculating the target pressure, the control circuit can adjust the flushing fluid flow rate to maintain the flushing line pressure at the target pressure. When the rotation speed of the ventricular assist device 30 changes, the pumping flow of the ventricular assist device 30 will also change, causing the blood pressure in the ventricular assist device 30 to change. Therefore, during the operation of the flushing device 10, if the rotation speed of the ventricular assist device 30 changes, the control circuit can use the pressure detected by the pressure sensor 130 after the rotation speed of the ventricular assist device 30 changes as the first pressure, and then use the above method to recalculate the target pressure.

[0069] The flushing liquid delivered by the flushing device 10 has a certain viscosity. After the flushing device 10 has been running for a period of time, the flushing liquid in the flushing pipeline 400 may coagulate together, or the flushing liquid may stick or adhere to the inner wall of the pipeline, the filter screen arranged in the pipeline, and the gap of the motor, or the blood in the human body may coagulate or stick to the gap of the motor. This situation may cause a blocking tendency in the flushing pipeline 400, that is, due to the coagulation, sticking, and adhesion of the flushing liquid, the flushing liquid in the flushing pipeline 400 is blocked but does not reach a blocking state, or due to the coagulation, sticking, and adhesion of blood, the gap of the motor is blocked but does not reach a blocking state, that is, the pipeline in an abnormal state can also deliver flushing liquid, but the flow rate of the delivered flushing liquid is less than the fluid flow rate corresponding to the current flushing pipeline outlet pressure. When there is blockage in the flushing pipeline 400 or the motor gap, the flushing pipeline pressure will gradually increase. Therefore, during the operation of the flushing device 10, the control circuit can monitor the flushing pipeline pressure in real time. If the flushing pipeline pressure suddenly increases by a preset value, it can be considered that there is a blockage in the current flushing pipeline 400 or the motor gap. The control circuit can use the pressure detected by the current pressure sensor 130 as the first pressure to recalculate the target pressure.

[0070] In an embodiment of the present application, the control circuit recalculates the target pressure when the flushing line pressure changes or the ambient pressure of the flushing line 400 changes, and can maintain the pressure barrier between the blood in the cannula of the ventricular assist device 30 and the distal end of the motor in real time, avoiding excessive or insufficient flushing line pressure, thereby ensuring the safe operation of the ventricular assist device 30.

[0071] In a possible example, when it is necessary to deliver a target drug, the method further includes: acquiring a concentration of the target drug; and re-determining the target flushing fluid flow rate according to the concentration of the target drug.

[0072] When the patient needs to precisely control the input of the target drug, the control circuit can calculate the target flushing fluid flow rate according to the concentration of the target drug, and then determine the target pressure according to the target flushing fluid flow rate. For example, the target drug can be heparin anticoagulant drugs, glucose, vascular drugs, diuretics, etc.

[0073] For example, when a patient needs to accurately control the infusion of heparin at 150 IU / h, if the current heparin concentration of the flushing fluid is 25 IU / ml, the target flushing fluid flow rate is 6 mL / h. The control circuit can determine the second pipeline pressure drop corresponding to the target flushing fluid flow rate from the second pressure curve, and then substitute the second pressure and the re-determined second pipeline pressure drop into the target formula to recalculate the target pressure.

[0074] It can be seen that the present application proposes a pressure adaptive method. After the flushing device is connected to the ventricular assist device, a first pressure is obtained, which is the flushing line pressure when the pump assembly drives the flushing liquid at a first flushing liquid flow rate; a target flushing liquid flow rate flowing into the flushing line is calculated according to the first pressure; a target pressure is calculated according to the target flushing liquid flow rate, so that the outlet pressure of the flushing line is greater than a second pressure, which is the environmental pressure of the flushing line. The present application calculates a suitable flushing liquid flow rate according to the currently detected flushing line pressure, and then calculates the optimal flushing line pressure according to the flushing liquid flow rate, so that the outlet pressure of the flushing line is greater than its environmental pressure in real time, so that the pressure barrier between the blood and the motor in the ventricular assist device remains in a stable state, thereby ensuring the safe operation of the ventricular assist device.

[0075] The above mainly introduces the scheme of the embodiment of the present application from the perspective of the execution process on the method side. It is understandable that in order to realize the above functions, the network device includes a hardware structure and / or software module corresponding to each function. Those skilled in the art should easily realize that, in combination with the units and algorithm steps of each example described in the embodiment provided in this article, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0076] By way of example, the present application also provides a control circuit for a flushing device, wherein the flushing device includes a flushing pipeline for conveying flushing fluid and a pump assembly for driving the flow of flushing fluid, and the control circuit includes one or more processors, and the one or more processors are used to: obtain a first pressure after the flushing device and the ventricular assist device are in operation, the first pressure being the flushing pipeline pressure when the pump assembly drives the flushing fluid at a first flushing fluid flow rate; calculate a target flushing fluid flow rate flowing into the flushing pipeline based on the first pressure; calculate a target pressure based on the target flushing fluid flow rate so that the outlet pressure of the flushing pipeline is greater than a second pressure, the second pressure being the ambient pressure of the flushing pipeline.

[0077] For example, the present application also provides a ventricular assist system, the ventricular assist system comprising:

[0078] ventricular assist device;

[0079] a flushing device for providing flushing fluid to the ventricular assist device, the flushing device comprising a flushing pipeline for conveying the flushing fluid and a pump assembly for driving the flushing fluid to flow;

[0080] A control circuit for controlling the operation of the ventricular assist device and the pump assembly, wherein the control circuit is used to execute part or all of the steps described in the above method.

[0081] Among them, the control circuit of each of the above schemes has the function of implementing the corresponding steps performed by the medical device in the above method; the functions can be implemented by hardware, or by hardware executing corresponding software.

[0082] In the embodiments of the present application, the control circuit may also be a chip or a chip system, such as a system on chip (SoC).

[0083] See also Figure 6 , Figure 6 It is a structural diagram of a medical device provided in an embodiment of the present application, wherein the medical device comprises: one or more processors, one or more memories, one or more communication interfaces, and one or more programs; the one or more programs are stored in the memories and are configured to be executed by the one or more processors.

[0084] The above program includes instructions for performing the following steps:

[0085] After the flushing device and the ventricular assist device are in operation, obtaining a first pressure, the first pressure being the flushing line pressure when the pump assembly drives the flushing fluid at a first flushing fluid flow rate;

[0086] calculating a target flushing liquid flow rate flowing into the flushing pipeline according to the first pressure;

[0087] The target pressure is calculated according to the target flushing liquid flow rate so that the outlet pressure of the flushing pipeline is greater than a second pressure, where the second pressure is the ambient pressure of the flushing pipeline.

[0088] Among them, all relevant contents of each scenario involved in the above method embodiment can be referred to the functional description of the corresponding functional module, which will not be repeated here.

[0089] It should be understood that the above-mentioned memory may include a read-only memory and a random access memory, and provide instructions and data to the processor. A portion of the memory may also include a non-volatile random access memory. For example, the memory may also store information about the device type.

[0090] In the embodiment of the present application, the processor of the above-mentioned device may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0091] It should be understood that the "at least one" involved in the embodiments of the present application refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0092] Furthermore, unless otherwise specified, ordinal numbers such as "first" and "second" mentioned in the embodiments of the present application are used to distinguish multiple objects, and are not used to limit the order, timing, priority or importance of multiple objects. For example, the first information and the second information are only used to distinguish different information, and do not indicate the difference in content, priority, sending order or importance of the two types of information.

[0093] In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in a processor or an instruction in the form of software. The steps of the method disclosed in conjunction with the embodiment of the present application can be directly embodied as a hardware processor for execution, or a combination of hardware and software units in a processor for execution. The software unit can be located in a storage medium mature in the art such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor executes the instructions in the memory, and completes the steps of the above method in conjunction with its hardware. To avoid repetition, it is not described in detail here.

[0094] An embodiment of the present application also provides a computer storage medium, wherein the computer storage medium stores a computer program for electronic data exchange, and the computer program enables a computer to execute part or all of the steps of any method recorded in the above method embodiments.

[0095] The present application also provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program, and the computer program is operable to cause a computer to execute some or all of the steps of any method described in the above method embodiment. The computer program product may be a software installation package.

[0096] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0097] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0098] In the several embodiments provided in the present application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are only schematic, such as the division of the above-mentioned units, which is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0099] The units described above as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0100] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0101] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or all or part of the technical solution, can be embodied in the form of a software product, which is stored in a memory and includes several instructions for a computer device (which can be a personal computer, server or TRP, etc.) to execute all or part of the steps of the various embodiments of the present application. The aforementioned memory includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.

[0102] A person skilled in the art may understand that all or part of the steps in the various methods of the above embodiments may be completed by instructing the relevant hardware through a program, and the program may be stored in a computer-readable memory, which may include a flash drive, ROM, RAM, a magnetic disk or an optical disk, etc.

[0103] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A pressure adaptive method, characterized in that: Applied to a flushing device, the flushing device includes a flushing pipeline for conveying a flushing liquid and a pump assembly for driving the flushing liquid to flow, the method includes: After the flushing device and the ventricular assist device are in operation, obtaining a first pressure, the first pressure being the flushing line pressure when the pump assembly drives the flushing fluid at a first flushing fluid flow rate; calculating a target flushing liquid flow rate flowing into the flushing pipeline according to the first pressure; The target pressure is calculated according to the target flushing liquid flow rate so that the outlet pressure of the flushing pipeline is greater than a second pressure, where the second pressure is the ambient pressure of the flushing pipeline.

2. The method according to claim 1, characterized in that The step of calculating a target flushing liquid flow rate flowing into the flushing pipeline according to the first pressure includes: Acquire a first pressure curve, where the first pressure curve is a curve of the relationship between the second pressure and the flushing pipeline pressure at the first flushing liquid flow rate; Determining a third pressure corresponding to the preset pressure from the first pressure curve; The target flushing fluid flow rate is calculated according to the first pressure and the third pressure.

3. The method according to claim 2, characterized in that The step of calculating the target flushing liquid flow rate according to the first pressure and the third pressure includes: Acquire a second pressure curve, where the second pressure curve is a curve of the relationship between the flushing fluid flow rate and the flushing line pressure when the flushing device is not connected to the ventricular assist device; determining a first pipeline pressure drop corresponding to the first flushing liquid flow rate according to the second pressure curve; calculating the second pressure according to the first pressure and the third pressure; Acquire a third pressure curve, wherein the third pressure curve is a curve of the relationship between the flushing liquid flow rate and the flushing pipeline pressure under the second pressure; calculating an estimated pressure based on the first pipeline pressure drop and the second pressure; The target flushing fluid flow rate corresponding to the estimated pressure is determined from the third pressure curve.

4. The method according to claim 3, characterized in that The step of calculating the target pressure according to the target flushing fluid flow rate comprises: Determining a second pipeline pressure drop corresponding to the target flushing liquid flow rate from the second pressure curve; Substitute the second pipeline pressure drop and the second pressure into the target formula to calculate the target pressure. The target formula is P=k(ΔP+P b ), ΔP is the pipeline pressure drop, Pb is the ambient pressure of the flushing pipeline, k is the adjustment coefficient, and k is greater than 1.

5. The method according to claim 1, characterized in that The method further comprises: adjusting the flushing liquid flow rate of the flushing device to maintain the flushing line pressure at the target pressure; When the rotation speed of the ventricular assist device changes or the fluctuation value of the flushing circuit pressure exceeds a preset value, the target pressure is recalculated.

6. The method according to claim 1, characterized in that When it is necessary to deliver the target drug, the method further comprises: obtaining the concentration of the target drug; The target flushing fluid flow rate is re-determined according to the concentration of the target drug.

7. The method according to any one of claims 1 to 6, characterized in that: The target pressure is within a preset pressure range, and the preset pressure range is 300 mmHg to 1100 mmHg.

8. A control circuit for a flushing device, characterized in that: The flushing device includes a flushing pipeline for conveying a flushing liquid and a pump assembly for driving the flushing liquid to flow, and the control circuit includes one or more processors, and the one or more processors are used to: After the flushing device and the ventricular assist device are in operation, obtaining a first pressure, the first pressure being the flushing line pressure when the pump assembly drives the flushing fluid at a first flushing fluid flow rate; calculating a target flushing liquid flow rate flowing into the flushing pipeline according to the first pressure; The target pressure is calculated according to the target flushing liquid flow rate so that the outlet pressure of the flushing pipeline is greater than a second pressure, where the second pressure is the ambient pressure of the flushing pipeline.

9. A ventricular assist system, characterized in that: The ventricular assist system comprises: ventricular assist device; A flushing device for providing flushing fluid to the ventricular assist device, the flushing device comprising a flushing pipeline for conveying the flushing fluid and a pump assembly for driving the flushing fluid to flow; A control circuit for controlling the operation of the ventricular assist device and the pump assembly, wherein the control circuit is used to perform the steps in the method according to any one of claims 1 to 7.

10. A medical device, characterized in that: The method comprises a processor, a memory and a communication interface, wherein the memory stores one or more programs, and the one or more programs are executed by the processor, and the one or more programs include instructions for executing the steps in the method according to any one of claims 1 to 7.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program for electronic data exchange, wherein the computer program enables a computer to execute the steps of the method according to any one of claims 1 to 7.

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