CN117180610A

CN117180610A - Flushing fluid control method and device

Info

Publication number: CN117180610A
Application number: CN202311470474.8A
Authority: CN
Inventors: 陈仕章; 余顺周
Original assignee: Shenzhen Core Medical Technology Co Ltd
Current assignee: Shenzhen Core Medical Technology Co Ltd
Priority date: 2023-11-07
Filing date: 2023-11-07
Publication date: 2023-12-08
Anticipated expiration: 2043-11-07
Also published as: CN117180610B

Abstract

The application provides a flushing fluid control method and a flushing fluid control device, wherein the method comprises the following steps: acquiring a target current set, wherein the target current set is a current set sampled when the ventricular assist device operates at a target rotating speed in a target cycle time; judging whether the ventricular assist device is abnormal according to the target current set; when the ventricular assist device is abnormal, the flushing device is controlled to flush so as to enable the ventricular assist device to return to normal. According to the application, whether the ventricular assist device is abnormal or not is judged by monitoring the current of the ventricular assist device, and then the ventricular assist device is flushed by controlling the flushing device when the ventricular assist device is abnormal, so that the formation of blood blocking the ventricular assist device or thrombus can be prevented, further, the operation failure of the ventricular assist device caused by the blood entering the motor can be effectively prevented, and the continuous and effective operation of the ventricular assist device can be ensured.

Description

Flushing fluid control method and device

Technical Field

The application relates to the technical field of medical instruments, in particular to a flushing fluid control method and device.

Background

The interventional ventricular assist device has small volume, high rotating speed, easy implantation, small operation wound and short-term assistance, and is mainly used for the protection of high-risk percutaneous coronary intervention PCI operation. The impeller of the interventional ventricular assist device is connected with the motor through a transmission shaft, and gaps exist between the transmission shaft and the motor and between the transmission shaft and the shaft sleeve. When the ventricular assist device is operated, blood enters the gap due to the pressure of the blood, and the blood pump is stopped due to the destructive coagulation formed by the high-speed rotation of the transmission shaft, so that the pressure of the blood is maintained to be greater than that of the external blood and continuously washed outwards from the interior of the ventricular assist device through the gap between the transmission shaft and the shaft sleeve by using flushing liquid, so that the pressure barrier between the blood and the motor is maintained, and the blood is prevented from entering the motor.

At present, flushing fluid control adopted by an interventional pump ventricular assist device is a flushing mode with fixed pressure, and the flow of flushing fluid is not regulated according to the operation change of the ventricular assist device.

Disclosure of Invention

Based on the above, the embodiment of the application provides a flushing liquid control method and a flushing liquid control device, which improve the flushing effect and prevent blood damage caused by blood blockage or overhigh temperature rise.

In a first aspect, an embodiment of the present application provides a method for controlling a flushing fluid, applied to a ventricular assist system, where the ventricular assist system includes a ventricular assist device, and a flushing device connected to the ventricular assist device; the method comprises the following steps:

acquiring a target current set, wherein the target current set is a current set sampled when the ventricular assist device operates at a target rotating speed in a target period time;

judging whether the ventricular assist device is abnormal according to the target current set;

when the ventricular assist device is abnormal, the flushing device is controlled to flush so as to enable the ventricular assist device to return to normal;

wherein the determining whether the ventricular assist device is abnormal according to the target current set includes: calculating an ith current ratio, wherein the ith current ratio is a ratio of an ith+1 current to an ith current, the ith+1 current is an ith+1 sampling current in the target current set, the ith current is an ith sampling current in the target current set, and the i is a positive integer; let i=i+1, repeat the above steps until i is greater than or equal to m, where m is the sampling number; and if the ith current ratio is larger than a preset value, determining that the ventricular assist device operates abnormally, otherwise, determining that the ventricular assist device operates normally.

In a second aspect, an embodiment of the present application provides a control unit, where the control unit includes one or more processors, where the one or more processors are configured to:

when the ventricular assist device is abnormal, controlling the flushing device to flush so as to enable the ventricular assist device to return to normal;

wherein, in judging whether the ventricular assist device is abnormal according to the target current set, the control unit is specifically configured to: calculating an ith current ratio, wherein the ith current ratio is a ratio of an ith+1 current to an ith current, the ith+1 current is an ith+1 sampling current in the target current set, the ith current is an ith sampling current in the target current set, and the i is a positive integer; let i=i+1, repeat the above steps until i is greater than or equal to m, where m is the sampling number; and if the ith current ratio is larger than a preset value, determining that the ventricular assist device operates abnormally, otherwise, determining that the ventricular assist device operates normally.

In a third aspect, embodiments of the present application provide a ventricular assist system comprising:

a ventricular assist device;

flushing device

A controller for:

wherein, in judging whether the ventricular assist device is abnormal according to the target current set, the controller is specifically configured to: calculating an ith current ratio, wherein the ith current ratio is a ratio of an ith+1 current to an ith current, the ith+1 current is an ith+1 sampling current in the target current set, the ith current is an ith sampling current in the target current set, and the i is a positive integer; let i=i+1, repeat the above steps until i is greater than or equal to m, where m is the sampling number; and if the ith current ratio is larger than a preset value, determining that the ventricular assist device operates abnormally, otherwise, determining that the ventricular assist device operates normally.

In a fourth aspect, embodiments of the present application provide a medical device comprising a processor, a memory, a communication interface, and one or more programs stored in the memory and configured to be executed by the processor, the programs comprising instructions for performing part or all of the steps described in the method of the first aspect above.

In a fifth aspect, embodiments of the present application provide a computer-readable storage medium storing a computer program for electronic data exchange, wherein the computer program causes a computer to execute some or all of the steps described in the method of the first aspect.

In a sixth aspect, embodiments of the present application provide a computer program product, wherein the computer program product comprises a non-transitory computer readable storage medium storing a computer program, the computer program being operable to cause a computer to perform some or all of the steps described in the method according to the first aspect of the embodiments of the present application. The computer program product may be a software installation package.

According to the technical scheme provided by the application, a target current set is obtained, wherein the target current set is a current set sampled when the ventricular assist device operates at a target rotating speed in a target period time; judging whether the ventricular assist device is abnormal according to the target current set; when the ventricular assist device is abnormal, the flushing device is controlled to flush so as to enable the ventricular assist device to return to normal. According to the application, whether the ventricular assist device is abnormal or not is judged by monitoring the current of the ventricular assist device, and then the ventricular assist device is flushed by controlling the flushing device when the ventricular assist device is abnormal, so that the formation of blood blocking the ventricular assist device or thrombus can be prevented, further, the operation failure of the ventricular assist device caused by the blood entering the motor can be effectively prevented, and the continuous and effective operation of the ventricular assist device can be ensured.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a block diagram of a ventricular assist system provided in an embodiment of the application;

FIG. 2 is a block diagram of a flushing device according to an embodiment of the present application;

FIG. 3 is a schematic flow chart of a method for controlling rinse liquid according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a medical device according to an embodiment of the present application.

Detailed Description

For better understanding of the technical solutions of the present application by those skilled in the art, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the description of the embodiments of the application without making any inventive effort, are intended to fall within the scope of the application.

The terms first, second and the like in the description and in the claims and in the above-described figures are used for distinguishing between different objects and not necessarily for describing a sequential or chronological order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, software, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In the present application, as shown in fig. 1, the ventricular assist system includes a ventricular assist device, a control device, and an irrigation device. The ventricular assist device is implanted in a patient, percutaneously inserted into the aorta through the femoral artery, and passed through the aorta into the left ventricle such that a proximal end of the ventricular assist device is positioned within the aorta and a distal end of the ventricular assist device is positioned within the left ventricle, whereby blood within the left ventricle is pumped into the aorta through the ventricular assist device to provide partial or complete assistance to the circulatory system of the heart. For example, the ventricular assist device may be percutaneously inserted into the aorta via the axillary artery and passed through the aorta into the left ventricle.

Wherein the controller and the flushing device are located outside the body, and the controller is electrically connected with the ventricular assist device and the flushing device respectively. The controller is used for realizing the functions of controlling and displaying data of the ventricular assist device and the flushing device, fault detection and alarming, data recording and the like. The irrigation device is used to maintain a pressure barrier between the blood and the motor. The flushing line of the flushing device is connected to the motor bearing in the ventricular assist device, and the blood is isolated from the motor by the fluid pressure formed by the flushing fluid in the opposite direction to the blood flow, preventing the blood from entering the motor.

As shown in fig. 2, the above-mentioned flushing device includes a flushing liquid bag, a driving motor, a flushing chamber and a flushing pipe. The flushing liquid bag is connected with a flushing pipeline which is connected with the flushing cavity. The flushing pipeline passes through the driving motor, so that the flow speed of flushing liquid is controlled by controlling the movement of the driving motor, wherein the rotation of the driving motor drives the shaft to rotate after passing through the mechanical transmission device (gear reduction mechanism), the peristaltic sheet is enabled to generate wave-shaped movement by the cam on the shaft according to a certain time sequence, the flushing pipeline between the peristaltic sheet and the extrusion plate is extruded by the peristaltic sheet, and liquid in the flushing pipeline is enabled to be subjected to a continuous thrust force related to the movement time sequence of the peristaltic sheet, so that the liquid flows, and the effect of flushing liquid flowing is achieved. The flushing liquid is input into the flushing cavity through the flushing pipeline, an output port of the flushing cavity is connected with a transmission shaft in the ventricular assist device, and the flushing liquid flowing into the transmission shaft and opposite to the flowing direction of the blood also forms certain pressure through the fluid pressure in the flushing cavity, so that the blood is isolated from the motor, and the blood is prevented from entering the motor.

Wherein the flushing liquid can be water, a mixture of water and glycerin in different proportions. For example, dextrose and heparin solutions may also be included in the rinse.

The irrigation device also includes a sensor assembly including a pressure sensor disposed within the irrigation chamber. During operation of the irrigation device, the pressure sensor monitors the pressure in the irrigation chamber in real time, and by control, maintains a pressure barrier between the blood and the motor.

During the operation of the ventricular assist device, blood enters into the gaps between the transmission shaft and the motor and between the transmission shaft and the shaft sleeve of the ventricular assist device, and the operation of the ventricular assist device is abnormal or even stopped due to the damage and solidification of the blood along with the high-speed rotation of the transmission shaft, so that the pressure of the blood is maintained to be larger than that of the external blood and the external blood is continuously flushed outwards through the gaps between the transmission shaft and the shaft sleeve by using flushing liquid to fill the interior of the ventricular assist device. The current control modes of the flushing fluid adopted by the ventricular assist device mainly comprise two modes, wherein the first mode is to set a fixed flushing fluid flow target value, and continuously pass through a gap between a transmission shaft and a shaft sleeve of the ventricular assist device at a fixed flushing fluid flow rate so as to ensure positive pressure inside and outside the ventricular assist device and prevent blood from entering the ventricular assist device; the second is to set a fixed target value of the flushing fluid pressure, and ensure that the flushing fluid pressure fluctuates around the set target value by finely adjusting the flushing fluid flow, so that the internal and external positive pressure of the ventricular assist device is always maintained. However, the first flushing fluid control method cannot adapt to the pressure difference caused by the individual difference of the ventricular assist device, i.e. a fixed flushing fluid flow is set, and the pressure difference caused by the different gaps between the transmission shaft and the shaft sleeve is different, so that when the pressure in the ventricular assist device cannot be greater than the ambient pressure, blood can enter the motor of the ventricular assist device. The second flushing fluid control mode is not related to the operation monitoring of the ventricular assist device, and the control of the flushing fluid cannot sense the operation state of the ventricular assist device, so that the abnormal change of the ventricular assist device cannot be changed, and the abnormal operation of the ventricular assist device is prevented.

Based on the above, the application provides a flushing fluid control method, which can improve the flushing effect of the flushing device on the ventricular assist device by monitoring the current change of the ventricular assist device and adjusting the flow and/or the pressure of the flushing fluid according to the current change, so as to prevent the ventricular assist device from being blocked by blood or form thrombus, further effectively prevent the problem of operation failure of the ventricular assist device caused by the blood entering the ventricular assist device, and ensure the continuous and effective operation of the ventricular assist device.

In connection with the above description, the present application is described below from the viewpoint of a method example.

Referring to fig. 3, fig. 3 is a flowchart of a flushing fluid control method according to an embodiment of the application, which is applied to the ventricular assist system shown in fig. 1. As shown in fig. 3, the method includes the following steps.

S310, acquiring a target current set, wherein the target current set is a current set sampled when the ventricular assist device operates at a target rotating speed in a target cycle time.

During operation of the ventricular assist device in the patient, the flow rate of the blood pumped through the ventricular assist device is dependent upon the resistance of the ventricular assist device to perform work to pump the blood from the left ventricle to the aorta. The amount of work done by the ventricular assist device can be quantified as the amount of current that needs to be provided to the motor, i.e., the motor current corresponds to the amount of current delivered to the motor of the ventricular assist device when the ventricular assist device is operating in a patient. The change in current flowing through the motor by the ventricular assist device can be used to characterize the operational state of the ventricular assist device.

For example, in normal operation of the ventricular assist device, the current flowing through the motor is proportional to the rotational speed of the ventricular assist device, and at the same rotational speed the current remains substantially the same, i.e., the current change is approximately equal to 0; when the ventricular assist device operates abnormally, for example, thrombus is formed at the bottom of the impeller or blood coagulation exists between the transmission shaft and the bearing clearance, the ventricular assist device needs to overcome more resistance to do work and needs to consume more power consumption, so that the current flowing through the motor can be gradually increased.

Wherein the target cycle time is greater than or equal to a cardiac cycle of a target user, the target user being a user using the ventricular assist device.

In the present application, the current flowing through the motor may be measured by providing a phase current detection circuit or any other suitable means, such as a current sensor. In the operation process of the ventricular assist device, the current detection device can detect the current flowing through the motor in real time and feed the current back to the control unit for storage and analysis, and the control unit can sample the current in each target period time to obtain a target current set, so that whether the current ventricular assist device is abnormal in operation or not is judged according to the target current set.

The target cycle time may also be set to a value that is greater than the range of normal human cardiac cycles, such as 1s, 1.2s, 1.5s, etc., for example.

S320, judging whether the ventricular assist device is abnormal according to the target current set.

In the application, the impeller rotating speed is slowed down or even stopped due to the entering of blood in the gap between the transmission shaft and the shaft sleeve, and in the process, more power consumption is required by the motor to maintain the rotating speed of the impeller, so that whether the operation of the current ventricular assist device is abnormal can be judged through the change of current.

Optionally, the determining whether the ventricular assist device is abnormal according to the target current set includes: calculating an ith current ratio, wherein the ith current ratio is a ratio of an ith+1 current to an ith current, the ith+1 current is an ith+1 sampling current in the target current set, the ith current is an ith sampling current in the target current set, and the i is a positive integer; let i=i+1, repeat the above steps until i is greater than or equal to m, the m sampling times; and if the ith current ratio is larger than a preset value, determining that the ventricular assist device operates abnormally, otherwise, determining that the ventricular assist device operates normally.

Among other things, ventricular assist device abnormalities may include: the gap between the transmission shaft and the shaft sleeve is coagulated with blood, the gap between the transmission shaft and the stator of the motor is coagulated with blood, and the bottom of the impeller is thrombosed.

The control unit may arrange the sampling currents in the target current set in ascending order of time sequence, and determine the change of the current by calculating the ratio of adjacent currents. When the rotating speed of the ventricular assist device is unchanged and the current flowing through the motor is continuously increased in the target cycle time, determining that the current ventricular assist device is abnormal; otherwise, the current ventricular assist device is considered to be functioning properly.

Specifically, the control unit calculates the ratio S2/S1 of the second sampled current S2 to the first sampled current S1, if the value of S2/S1 is greater than the preset value p, then calculates the ratio S3/S2 of the third sampled current S3 to the second sampled current S2 again, if the value of S3/S2 is also greater than the preset value p, then continues to calculate the ratio S4/S3 of the fourth sampled current S4 to the third sampled current S3 until the ratio Sm/S (m-1) of the mth sampled current Sm to the mth-1 sampled current S (m-1) is calculated, and if the value of Sm/S (m-1) is also greater than the preset value p, then determines that the current ventricular assist device is abnormal in operation, that is, there is a problem that there is blood coagulation in the gap between the transmission shaft and the shaft sleeve, blood in the gap between the transmission shaft and the stator of the motor, and/or thrombus formation in the impeller bottom, the effect of the flushing device needs to be improved, and the blood blocking or thrombus formation is prevented; if any one of S2/S1, S3/S2, S4/S3, … … Sm/S (m-1) is less than or equal to the preset value p, the current ventricular assist device is considered to be operating normally.

In one possible example, the i-th current ratio is the ratio of the i+j-th current to the i-j-th current, where j is a positive integer.

Specifically, the control unit may calculate the ratio S (m/2)/S (m/2-1) of the current Sm/2 sampled for the m/2 th time to the current S m/2-1 sampled for the m/2-1 th time, if the value of S (m/2)/S (m/2-1) is greater than the preset value p or exceeds the preset threshold range, continuously compare the ratio S (m/2+1) of the current S (m/2+1) sampled for the m/2+1 th time with the current S (m/2-1) sampled for the m/2-1 th time, if the value of S (m/2+1)/S (m/2-1) is also greater than the preset value p or exceeds the preset threshold range, then the ratio S (m/2+2)/S (m/2-2) of the current S (m/2+2) of the m/2-2 th sampling to the current S (m/2-2) of the m/2-2 th sampling is calculated again until the ratio Sm/S1 of the current Sm of the m-th sampling to the current S1 of the 1 st sampling is calculated, if Sm/S1 is also larger than a preset value p or exceeds a preset threshold range, the abnormal operation of the current ventricular assist device is determined, namely the problems that blood coagulation exists in a gap between a transmission shaft and a shaft sleeve, blood exists in a gap between the transmission shaft and a stator of a motor, and/or thrombus exists at the bottom of an impeller exist, the flushing effect of the flushing device needs to be improved, preventing blood blockage or thrombosis; if any one of S (m/2)/S (m/2-1), S (m/2+1)/S (m/2-1), S (m/2+2)/S (m/2-2), … … Sm/S1 is less than or equal to a preset value p or exceeds a preset threshold range, the current ventricular assist device is considered to be operating normally.

S330, when the ventricular assist device is abnormal, controlling the flushing device to flush so as to enable the ventricular assist device to recover to be normal

When detecting that the ventricular assist device is abnormal in operation, namely that thrombus is formed at the bottom of the impeller or that blood is coagulated between the transmission shaft and the bearing clearance is detected, the effect of flushing the bearing clearance of the ventricular assist device and the bottom of the impeller can be achieved by changing the flow and/or the pressure of flushing liquid, so that the thrombus at the bottom of the impeller can be prevented, the operation failure of the ventricular assist device caused by the blood entering the motor can be prevented, the service life of the ventricular assist device can be prolonged, and longer assist time can be provided.

Optionally, when the ventricular assist device is abnormal, the flushing device is controlled to flush, so as to make the ventricular assist device return to normal, including: controlling the flow rate of the flushing liquid to be increased to a second flow rate, wherein the second flow rate is n times of the first flow rate when the pressure of the flushing liquid is greater than or equal to a pressure alarm threshold value, and the first flow rate is the average flushing liquid flow rate in the target period time; controlling the flow rate of the flushing liquid to be reduced from the second flow rate to the first flow rate until the flushing liquid pressure is equal to a preset pressure value; repeating the steps until the ventricular assist device operates normally.

Wherein, when the current abnormality in the operation of the ventricular assist device is determined, the abnormality can be prevented from being worsened by flushing the flushing liquid. Specifically, the flushing device is controlled to adjust the flushing fluid flow to n times of the current flushing fluid flow or n times of the average flushing fluid flow in the target period time, namely, the flushing fluid flow is increased from the first flow to the second flow, and the flushing device is controlled to continue for a period of time until the flushing fluid pressure is detected to reach a preset pressure alarm threshold value. And after the flushing liquid pressure reaches the preset pressure alarm threshold value, controlling the flushing device to adjust the flushing liquid flow to the flushing liquid flow before changing, namely reducing the flushing liquid flow from the first flow to the second flow for a period of time until the flushing liquid pressure is restored to the flushing liquid pressure before changing or the preset flushing liquid pressure. The ventricular assist device is repeatedly flushed for k times according to the flushing mode, so that the abnormal condition of the ventricular assist device is prevented from deteriorating, blood is prevented from being filled in the ventricular assist device, the service life of the ventricular assist device is prolonged, and the safety of a user is ensured.

In one possible example, the controlling the flushing device to flush the ventricular assist device to restore the ventricular assist device to the normal state when the ventricular assist device is abnormal includes: controlling the pressure of the flushing liquid to be increased to a second pressure which is n times of the first pressure, wherein the first pressure is the pressure of the flushing liquid when the ventricular assist device operates normally, and the first time is less than the target cycle time; controlling the flushing liquid pressure to be reduced to the first pressure and maintaining a second time period, wherein the first time period is longer than the second time period; repeating the steps until the ventricular assist device operates normally.

The flushing device can flush the ventricular assist device by adjusting the flow of flushing liquid, and can flush the ventricular assist device by adjusting the pressure of the flushing liquid.

Specifically, the control unit controls the flushing device to adjust the flushing liquid pressure to n times the current flushing liquid pressure or n times the average flushing liquid pressure in the target cycle time, i.e., to increase the flushing liquid pressure from the first pressure to the second pressure for a certain period of time, such as 2s, 5s, 10s, etc. And then controlling the flushing device to adjust the flushing liquid pressure to the flushing liquid pressure before changing, namely reducing the flushing liquid pressure from the first pressure to the second pressure for a period of time until the flushing liquid pressure returns to the flushing liquid pressure before changing or the preset flushing liquid pressure. The ventricular assist device is repeatedly flushed for k times according to the flushing mode, so that the abnormal condition of the ventricular assist device is prevented from deteriorating, blood is prevented from being filled in the ventricular assist device, the service life of the ventricular assist device is prolonged, and the safety of a user is ensured.

The second pressure is, for example, less than or equal to a preset pressure alarm threshold.

Optionally, the method further comprises: calculating a target average current and a target mean square error, wherein the target average current is a current average value in the target period time, and the target mean square error is a current variance value in the target period time; determining a target adjustment coefficient according to the target mean square error; and determining the n according to a target difference value and the target regulating coefficient, wherein the target difference value is a difference value between the target average current and a normal current, and the normal current is a current when the ventricular assist device operates normally at the target rotating speed.

The application can also determine the abnormal condition of the ventricular assist device according to the amplitude of the current change, calculate the current average value and the current mean square error in the target period time, and the current mean square error can reflect the change degree of the current. The control unit may store a mapping relationship between a preset mean square error and an adjustment coefficient in advance, and further determine a target adjustment coefficient corresponding to the target mean square error according to the mapping relationship. For example, the value range of the adjustment coefficient may be 0 to 1.

The control unit calculates a difference between the target average current and the normal current, which can reflect the degree of abnormality of the current, and the greater the difference between the target average current and the normal current, the greater the abnormality of the ventricular assist device. The control unit may calculate n, n= (1+ target adjustment coefficient) target difference value according to the target difference value and the target mean square error.

Furthermore, the application can also determine the flushing times k of the ventricular assist device according to the target difference value, wherein the larger the target difference value is, the larger the flushing times k are.

The method further comprises the steps of: calculating a target current ratio, wherein the target current ratio is the ratio of the ith current to a first current, the first current is a current value at a first moment, and the first moment is later than the target period time; if the target current ratio is larger than the preset value, controlling the flushing device to flush; otherwise, let i=i+1 until i=m.

In the application, after the flushing of the ventricular assist device is completed, the current in the current time and the current in the target period time can be compared, and whether the abnormality of the current ventricular assist device is relieved or solved is determined according to the ratio.

Specifically, comparing current Si at the current moment with current Sm adopted for the mth time in a target preset period, and if Si/Sm exceeds a set threshold range or a preset value p, flushing the ventricular assist device again according to the flushing mode; otherwise, the current ventricular assist device is considered to have resumed normal operation. The application judges the current operation state of the ventricular assist device by monitoring the current change of the ventricular assist device in real time, thereby starting the dynamic flushing of the flushing device when the ventricular assist device operates abnormally, preventing blood from entering the ventricular assist device and ensuring the effective operation of the ventricular assist device.

In the application, if the control unit adjusts the flushing fluid pressure or the flushing fluid flow of the flushing device to flush the ventricular assist device k times, the control unit can give an alarm when the current change of the ventricular assist device is still abnormal.

Illustratively, the method further comprises: when detecting that the rotation speed of the ventricular assist device changes, calculating a rotation speed difference value between a target rotation speed and a current rotation speed, and increasing the flushing fluid flow rate from the first flow rate to a third flow rate or increasing the flushing fluid pressure from the first pressure to the third pressure according to the rotation speed difference value.

Wherein as the rotational speed of the ventricular assist device increases, the flow rate pumped by the ventricular assist device increases, and thus the pressure of the blood within the ventricular assist device also increases, at which time the fluid pressure of the flushing device needs to be increased to maintain a pressure barrier between the blood and the motor. Similarly, when the rotation speed of the ventricular assist device is reduced, the flow of the flushing liquid is reduced to avoid the excessive flushing liquid from entering the human body, thereby causing injury to the human body.

The third flow and the third pressure are calculated according to a target formula, which can be expressed as:

wherein->For the third pressure>For the first pressure, +>For the difference in rotation speed>For flushing fluid viscosity +.>For the radius of the connection of the flushing line to the ventricular assist device, < >>And b is a fixed coefficient.

After the control unit calculates the third pressure according to the target formula, the control unit can further determine a third flow corresponding to the third pressure according to a mapping relation between the pre-stored pressure and the flushing flow. Wherein when the target rotation speed is reduced, the target formula is thatThe method comprises the steps of carrying out a first treatment on the surface of the When the target rotation speed increases, the target formula is +.>。

In one possible example, the method further comprises: and when the rotating speed of the ventricular assist device is synchronous with the cardiac cycle of the target user, acquiring the current cardiac cycle of the target user, and dynamically controlling the flushing fluid flow or the flushing fluid pressure of the flushing device according to the cardiac cycle.

In the present application, the ventricular assist device is a pulsatile ventricular assist device, i.e., the rotational speed of the ventricular assist device changes the same as the cardiac cycle of the patient. During ventricular systole, the rotational speed of the ventricular assist device increases and increases to a maximum value; during ventricular diastole, the rotational speed of the ventricular assist device is reduced and reduced to a minimum. The control unit may also control the irrigation fluid pressure or the change in the irrigation fluid flow rate of the irrigation device in synchronization with the change in the rotational speed of the ventricular assist device in order to maintain a pressure barrier between the blood and the motor. Namely, the flushing liquid pressure or flushing liquid flow rate is increased in the ventricular systole; the irrigation fluid pressure or irrigation fluid flow is reduced during ventricular diastole.

It can be seen that the application provides a flushing fluid control method, which acquires a target current set, wherein the target current set is a current set sampled when a ventricular assist device operates at a target rotating speed in a target cycle time; judging whether the ventricular assist device is abnormal according to the target current set; when the ventricular assist device is abnormal, the flushing device is controlled to flush so as to enable the ventricular assist device to return to normal. According to the application, whether the ventricular assist device is abnormal or not is judged by monitoring the current of the ventricular assist device, and then the ventricular assist device is flushed by controlling the flushing device when the ventricular assist device is abnormal, so that the formation of blood blocking the ventricular assist device or thrombus can be prevented, further, the operation failure of the ventricular assist device caused by the blood entering the motor can be effectively prevented, and the continuous and effective operation of the ventricular assist device can be ensured.

The foregoing description of the embodiments of the present application has been presented primarily in terms of a method-side implementation. It will be appreciated that the network device, in order to implement the above-described functions, includes corresponding hardware structures and/or software modules that perform the respective functions. Those of skill in the art will readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The present application provides, by way of example, a control unit comprising a controller having one or more processors configured to: acquiring a target current set, wherein the target current set is a current set sampled when the ventricular assist device operates at a target rotating speed in a target period time; judging whether the ventricular assist device is abnormal according to the target current set; when the ventricular assist device is abnormal, the flushing device is controlled to flush so as to enable the ventricular assist device to return to normal;

The present application also provides, as an example, a ventricular assist system including:

a ventricular assist device;

a flushing device;

a controller for:

The application also provides, as an example, a medical device comprising the control unit or the ventricular assist system described above.

Wherein, the control unit and the control device of each scheme have the function of realizing the corresponding steps executed by the medical equipment in the method; the functions may be implemented by hardware, or may be implemented by hardware executing corresponding software.

In an embodiment of the application, the control unit may also be a chip or a system of chips, for example: system on chip (SoC).

Referring to fig. 4, fig. 4 is a schematic structural diagram of a medical device according to an embodiment of the present application, where the medical device includes: 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 memory and configured to be executed by the one or more processors.

The program includes instructions for performing the steps of:

wherein said determining whether the ventricular assist device is abnormal based on the set of target currents comprises: calculating an ith current ratio, wherein the ith current ratio is a ratio of an ith+1 current to an ith current, the ith+1 current is an ith+1 sampling current in the target current set, the ith current is an ith sampling current in the target current set, and the i is a positive integer; let i=i+1, repeat the above steps until i is greater than or equal to m, where m is the sampling number; and if the ith current ratio is larger than a preset value, determining that the ventricular assist device operates abnormally, otherwise, determining that the ventricular assist device operates normally.

All relevant contents of each scenario related to the above method embodiment may be cited to the functional description of the corresponding functional module, which is not described herein.

It should be appreciated that the memory described above may include read only memory and random access memory and provide instructions and data to the processor. A portion of the memory may also include non-volatile random access memory. For example, the memory may also store information of the device type.

In an embodiment of the present application, the processor of the above apparatus may be a central processing unit (Central Processing Unit, CPU), which may also be other general purpose processors, digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

It should be understood that references to "at least one" in embodiments of the present application mean one or more, and "a plurality" means two or more. "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: a alone, a and B together, and B alone, wherein a, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (one) of a, b, or c may represent: a, b, c, a-b, a-c, b-c, or a-b-c, wherein a, b, c may be single or plural.

And, unless specified to the contrary, references to "first," "second," etc. ordinal words of embodiments of the present application are used for distinguishing between multiple objects and are not used for limiting the order, timing, priority, or importance of the multiple objects. For example, the first information and the second information are only for distinguishing different information, and are not indicative of the difference in content, priority, transmission order, importance, or the like of the two information.

In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in a processor or by instructions in the form of software. The steps of the method disclosed in connection with the embodiments of the present application may be embodied directly in a hardware processor for execution, or in a combination of hardware and software elements in the processor for execution. The software elements may be located in a random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in a memory, and the processor executes instructions in the memory to perform the steps of the method described above in conjunction with its hardware. To avoid repetition, a detailed description is not provided herein.

The embodiment of the present application also provides a computer storage medium storing a computer program for electronic data exchange, where the computer program causes a computer to execute some or all of the steps of any one of the methods described in the above method embodiments.

Embodiments of the present application also provide a computer program product comprising a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform part or all of the steps of any one of the methods described in the method embodiments above. The computer program product may be a software installation package.

It should be noted that, for simplicity of description, the foregoing method embodiments are all described as a series of acts, but it should be understood by those skilled in the art that the present application is not limited by the order of acts described, as some steps may be performed in other orders or concurrently in accordance with the present application. Further, those skilled in the art will also appreciate that the embodiments described in the specification are all preferred embodiments, and that the acts and modules referred to are not necessarily required for the present application.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to related descriptions of other embodiments.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and the division of elements, such as those described above, is merely a logical function division, and may be implemented in other manners, such as multiple elements or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, or may be in electrical or other forms.

The units described above as separate components may or may not be physically separate, and components shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiment of the present application.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units described above, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable memory. Based on such understanding, the technical solution of the present application may be embodied essentially or partly in the form of a software product or all or part of the technical solution, which is stored in a memory, and includes several instructions for causing a computer device (which may be a personal computer, a server, or TRP, etc.) to perform all or part of the steps of the method of the embodiments of the present application. And the aforementioned memory includes: a U-disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a removable hard disk, a magnetic disk, or an optical disk, or other various media capable of storing program codes.

Those of ordinary skill in the art will appreciate that all or a portion of the steps in the various methods of the above embodiments may be implemented by a program that instructs associated hardware, and the program may be stored in a computer readable memory, which may include: flash disk, ROM, RAM, magnetic or optical disk, etc.

The foregoing has outlined rather broadly the more detailed description of embodiments of the application, wherein the principles and embodiments of the application are explained in detail using specific examples, the above examples being provided solely to facilitate the understanding of the method and core concepts of the application; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present application, the present description should not be construed as limiting the present application in view of the above.

Claims

1. A method of controlling flushing fluid, characterized by being applied to a ventricular assist system comprising a ventricular assist device, a flushing device connected to the ventricular assist device; the method comprises the following steps:

2. The method according to claim 1, wherein the method further comprises:

calculating a target current ratio, wherein the target current ratio is the ratio of the ith current to a first current, the first current is a current value at a first moment, and the first moment is later than the target period time;

If the target current ratio is larger than the preset value, controlling the flushing device to flush;

otherwise, let i=i+1 until i=m.

3. The method of claim 1, wherein controlling the flushing device to flush to return the ventricular assist device to normal when the ventricular assist device is abnormal comprises:

controlling the flow rate of the flushing liquid to be increased to a second flow rate, wherein the second flow rate is n times of the first flow rate when the pressure of the flushing liquid is greater than or equal to a pressure alarm threshold value, and the first flow rate is the average flushing liquid flow rate in the target period time;

controlling the flow rate of the flushing liquid to be reduced from the second flow rate to the first flow rate until the flushing liquid pressure is equal to a preset pressure value;

the above steps are repeated k times.

4. The method of claim 1, wherein controlling the flushing device to flush to return the ventricular assist device to normal when the ventricular assist device is abnormal comprises:

controlling the pressure of the flushing liquid to be increased to a second pressure which is n times of the first pressure, wherein the first pressure is the pressure of the flushing liquid when the ventricular assist device operates normally, and the first time is less than the target cycle time;

Controlling the flushing liquid pressure to be reduced to the first pressure and maintaining a second time period, wherein the first time period is longer than the second time period;

the above steps are repeated k times.

5. The method of any of claims 1-4, wherein the target cycle time is greater than or equal to a cardiac cycle of a target user, the target user being a user using the ventricular assist device.

6. The method of claim 5, wherein the method further comprises:

calculating a target average current and a target mean square error, wherein the target average current is a current average value in the target period time, and the target mean square error is a current variance value in the target period time;

determining a target adjustment coefficient according to the target mean square error;

and determining the n according to a target difference value and the target regulating coefficient, wherein the target difference value is a difference value between the target average current and a normal current, and the normal current is a current when the ventricular assist device operates normally at the target rotating speed.

7. The method according to claim 4, wherein the method further comprises:

when detecting that the rotation speed of the ventricular assist device changes, calculating a rotation speed difference value between the target rotation speed and the current rotation speed;

And increasing the flushing fluid pressure from the first pressure to a third pressure according to the rotating speed difference value.

8. The method of claim 7, wherein the third pressure is calculated according to a target formula, the target formula expressed as:wherein, said->For said third pressure, said +.>For said first pressure, said +.>For the rotational speed difference, the +.>For flushing fluid viscosity, said->For the radius of the connection of the flushing line in the flushing device with the ventricular assist device, the +.>And b is a fixed coefficient.

9. A control unit comprising one or more processors configured to:

10. A ventricular assist system, the ventricular assist system comprising:

a ventricular assist device;

a flushing device;

a controller for:

11. A medical device comprising a processor, a memory and a communication interface, the memory storing one or more programs, and the one or more programs being executed by the processor, the one or more programs comprising instructions for performing the steps in the method of any of claims 1-8.

12. A computer readable storage medium storing a computer program for electronic data exchange, wherein the computer program causes a computer to perform the steps of the method according to any one of claims 1-8.