CN117282019A

CN117282019A - Abnormal position detection method and device

Info

Publication number: CN117282019A
Application number: CN202311579059.6A
Authority: CN
Inventors: ***; 余顺周
Original assignee: Shenzhen Core Medical Technology Co Ltd
Current assignee: Shenzhen Core Medical Technology Co Ltd
Priority date: 2023-11-24
Filing date: 2023-11-24
Publication date: 2023-12-26
Anticipated expiration: 2043-11-24
Also published as: CN117282019B

Abstract

The application provides an abnormal position detection method and device, wherein the method comprises the following steps: collecting a plurality of first operating parameter sets of the ventricular assist device at a first time; determining whether a target anomaly is present in a secondary flow path of the ventricular assist device, the secondary flow path being a region through which fluid flows from a gap between the impeller and the housing, according to the plurality of first operating parameter sets; collecting a plurality of second operation parameter sets of the ventricular assist device in a second time when the target abnormal object exists in the secondary flow channel; and determining the position of the target abnormal object according to the plurality of second operation parameter sets. According to the method, whether abnormal objects such as particles or thrombus exist between the impeller and the shell gap or not is judged through the operation parameters of the ventricular assist device, and then the specific position of the abnormal object in the gap is determined when the abnormal objects exist, so that the abnormal objects can be accurately positioned under the condition that the complexity of the mechanical design of the pump is not increased or the pump efficiency is reduced, and the follow-up accurate flushing of the abnormal objects such as the particles or thrombus is facilitated.

Description

Abnormal position detection method and device

Technical Field

The application relates to the technical field of medical equipment, in particular to an abnormal position detection method and device.

Background

Pumps used as mechanical circulatory support devices include pumping mechanisms for pumping fluid from one location to another, such as centrifugal, axial or magnetic suspension pumps for pumping blood from the heart to other parts of the body, by including impellers disposed in the pump housing to convey fluid through the pump housing from the inflow end to the outflow end of the pump, thereby performing the pumping function of the fluid.

Some current mechanical circulatory support devices use non-contact impeller suspension techniques to address support and energy consumption issues in high-level mechanical designs. During operation of the pump, high shear forces generated by the high speed rotation of the impeller can cause blood damage and clot to form thrombi in the bearing gap between the suspended impeller and the pump housing, thereby compromising blood compatibility and affecting operation of the pump.

Disclosure of Invention

The embodiment of the application provides an abnormal position detection method and device, which can realize accurate positioning of an abnormal object.

In a first aspect, an embodiment of the present application provides an abnormal position detection method applied to a ventricular assist device, where the ventricular assist device includes a housing, an impeller disposed in the housing and rotating in a suspended manner, and a sensor for detecting a distance between the impeller and the housing; the method comprises the following steps:

Acquiring a plurality of first operating parameter sets of the ventricular assist device over a first time period;

determining whether a target anomaly is present in a secondary flow path of the ventricular assist device according to the plurality of first operating parameter sets, the secondary flow path being a region through which fluid flows from a gap between the impeller and the housing;

collecting a plurality of second operating parameter sets of the ventricular assist device during a second time when the target anomaly exists in the secondary flow path, wherein the first time is longer than the second time;

and determining the position of the target abnormal object according to the plurality of second operation parameter sets.

In a second aspect, embodiments of the present application provide a control unit, where the control unit includes one or more processors configured to:

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

a housing;

an impeller disposed within the housing and configured to rotate in a suspended manner;

a sensor for detecting a distance between the impeller and the housing;

and a control unit for controlling the suspension rotation of the impeller, the control unit being configured to:

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, where the computer program causes a computer to perform 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, a plurality of first operation parameter sets of the ventricular assist device in the first time are collected; determining whether a target anomaly is present in a secondary flow path of the ventricular assist device, the secondary flow path being a region through which fluid flows from a gap between the impeller and the housing, according to the plurality of first operating parameter sets; collecting a plurality of second operation parameter sets of the ventricular assist device in a second time when the target abnormal object exists in the secondary flow channel; and determining the position of the target abnormal object according to the plurality of second operation parameter sets. According to the method, whether abnormal objects such as particles or thrombus exist between the impeller and the shell gap or not is judged through the operation parameters of the ventricular assist device, and then the specific position of the abnormal object in the gap is determined when the abnormal objects exist, so that the abnormal objects can be accurately positioned under the condition that the complexity of the mechanical design of the pump is not increased or the pump efficiency is reduced, and the follow-up accurate flushing of the abnormal objects such as the particles or thrombus is facilitated.

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 schematic diagram of a ventricular assist system according to an embodiment of the present disclosure;

FIG. 2 is a schematic cross-sectional view of a ventricular assist device according to an embodiment of the present disclosure;

FIG. 3 is a schematic cross-sectional view of an impeller resting on a first housing provided in an embodiment of the present application;

FIG. 4 is a schematic cross-sectional view of an impeller according to an embodiment of the present application resting on a second housing;

fig. 5 is a flow chart of an abnormal position detection method according to an embodiment of the present application;

fig. 6 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 are 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 without the exercise of inventive faculty, are intended to be within the scope of protection of the present application based on the description of the embodiments herein.

The terms first, second and the like in the description and in the claims of the present application and in the above-described figures, are used for distinguishing between different objects and not for describing a particular sequential 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 present 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.

"proximal" is defined herein as the end proximal to the operator; the "distal end" is defined as the end that is remote from the operator, i.e. the end that is close to the heart of the patient.

The medical apparatus to which the present application relates may be a ventricular assist device (Ventricular Assist Devices, VAD), such as an interventional ventricular assist device, an implantable ventricular assist device, or the like; the ventricular assist device may be a left ventricular assist device, a right ventricular assist device, or a biventricular assist device; 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 suspension pump, or the like.

The ventricular assist device may be attached to the heart via a ventricular connection assembly (e.g., a top ring, a ventricular cuff) that may be sutured to the heart and coupled to a blood pump, the other end of which may be connected to the ascending aorta via an outlet tube and/or an artificial blood vessel connected to the outlet tube, such that the VAD may effectively divert blood from the weakened ventricle and advance it to the aorta, thereby circulating to the remainder of the patient's vascular system, providing the patient with ventricular assist functions.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a ventricular assist system according to an embodiment of the present disclosure. As shown in fig. 1, the ventricular assist system includes a ventricular assist device 100, an external controller 200, and a transmission assembly 300 connecting the ventricular assist device 100 to the external controller 200. One end of the transmission assembly 300 is connected to a motor within the ventricular assist device 100 and the other end is connected through the abdominal skin of the patient to an external controller 200 disposed outside the body. The external controller 200 is used for monitoring the ventricular assist device 100, and can realize functions of controlling and displaying data, detecting faults, alarming, recording data and the like of the ventricular assist device 100. The transmission assembly 300 may be a percutaneous cable that may include one or more power supply cables, and one or more communication cables.

As shown in fig. 2-4, ventricular assist device 100 includes a housing assembly having an inlet tube and an impeller 20 for propelling a fluid. The housing assembly comprises a first housing and a second housing connected with the first housing, a cavity 10 is formed by the first housing and the second housing, a fluid inlet 14 and a fluid outlet 15 which are communicated with the cavity 10 are respectively formed in the housing assembly, and the fluid inlet 14 is formed in the first housing. The impeller 20 is capable of rotating in suspension within the chamber 10, and rotation of the impeller 20 is capable of generating centrifugal force to transport fluid so that fluid can enter the chamber 10 from the fluid inlet 14 and be output from the fluid outlet 15. Wherein a levitated rotation of the impeller 20 means that the impeller 20 is not in contact with the cavity wall of the chamber 10 when rotating.

Among other things, ventricular assist device 100 further includes a motor 30 and a sensor 40 for driving impeller 20 in levitating rotation. The second housing includes a first side wall 11, the first housing includes a second side wall 12, and the motor 30 includes a stator 31 and a rotor 32 arranged on both sides of the first side wall 11. Wherein, the stator 31 is fixed on the outer side of the first side wall 11 opposite to the chamber 10, and the corresponding rotor 32 is positioned in the chamber 10. Further, the rotor 32 is fixedly connected to the impeller 20, and when the stator 31 drives the rotor 32 to rotate in the chamber 10, the impeller 20 also rotates in synchronization with the rotor 32 in the chamber 10. The rotation of the impeller 20 can pressurize the fluid in the chamber 10, so that the fluid in the chamber 10 has a higher pressure, thereby realizing the fluid pressurizing effect of the blood pump.

In the embodiment of fig. 2, the first side wall 11 and the second side wall 12 are disposed parallel to each other, and the rotation axis 21 of the impeller 20 is perpendicular to both the first side wall 11 and the second side wall 12. The first sidewall 11 includes a first face 111 adjacent the chamber 10 and a second face 112 opposite the first face 111.

The ventricular assist device 100 further comprises a control unit 33, a sensor 40 being fixedly arranged between the stator 31 and the second face 112, the sensor 40 being arranged to measure the distance of the impeller 20 along the rotation axis 21 relative to the first face 111, the sensor 40 transmitting the measured distance value to the control unit 33. The control unit 33 is electrically connected to the stator 32 and the sensor 40, respectively, and the control unit 33 can determine the position of the impeller 20 in the chamber 10 according to the received distance value, that is, determine the distance between the impeller 20 and the first housing and the second housing, and further control the magnetic force between the stator 31 and the rotor 32 by controlling the current flowing through the stator 31, so as to control the rotation speed and the levitation position of the impeller 20.

The impeller 20 is annular in shape, the impeller 20 having a central bore 25, and the fluid inlet 14 is directly opposite the central bore 25 of the impeller 20. Impeller 20 further includes opposed first and second surfaces 22, 23, and a flow passage 24. The first surface 22 is opposite the second side wall 12, the second surface 23 is opposite the first side wall 11, and the central hole 25 penetrates the first surface 22 and the second surface 23. The flow channels 24 are plural, and the plural flow channels 24 extend radially along the annular impeller 20. The flow channel 24 is disposed between the first surface 22 and the second surface 23. The flow channel 24 communicates with the center hole 25, and after the fluid enters the center hole 25 of the impeller 20 from the fluid inlet 14, the fluid flows out of the impeller 20 from the flow channel 24, and the flow channel 24 is a main flow channel of the fluid. Adjacent flow channels 24 are separated by the vanes of the impeller 20. The fluid increases in flow velocity with the rotation of the impeller 20 within the flow passage 24, thereby achieving a pressurizing effect, and then flows out of the fluid outlet 15. The first surface 22 is located on the side of the impeller 20 facing the second side wall 12. The rotor 32 is accommodated in the impeller 20; specifically, the rotor 32 is disposed within the impeller 20 and proximate the second surface 23. When the impeller 20 is rotated in suspension within the chamber 10, a gap exists between the first surface 22 of the impeller 20 and the second sidewall 12, and a gap exists between the second surface 23 of the impeller 20 and the first sidewall 11 of the second housing. A secondary flow path is formed between the first surface 22 and the second side wall 12, and between the second surface 23 and the first side wall 11. After the fluid flows into the impeller 20, a small portion of the fluid flows out of the flow passage 24 of the impeller 20, and does not flow directly to the fluid outlet 15, but is re-introduced into the primary flow passage through the secondary flow passage.

Further, the rotor 32 may be composed of a plurality of magnets arranged at equal angular intervals along the same circle so that adjacent magnetic poles are different from each other. That is, magnets with N poles toward the motor 30 side and magnets with S poles toward the motor 30 side are alternately arranged at equal angular intervals along the same circle. The stator 31 may include a plurality of magnetic bodies provided along the same circle at equal angular intervals so as to face the plurality of magnets of the rotor 32, and the base ends of the plurality of magnetic bodies may be joined to one yoke, and each magnetic body may be wound with a coil. The adjacent magnetic bodies of the plurality of magnetic bodies in the stator 31 have opposite magnetic properties on the side facing the rotor 32, and the adjacent magnetic bodies of the plurality of magnetic bodies in the rotor 32 have opposite magnetic properties on the side facing the stator 31. That is, the magnetic bodies having the same magnetism in the stator 31 and the rotor 32 are symmetrically placed at intervals.

Further, the Control unit 33 is used for monitoring and controlling the start-up and subsequent running operations of the motor 30, including performing a three-phase Field Oriented Control (FOC) method. The control unit 33 may be a module independent of the stator 31 or may be built into the stator 31. In the embodiment of fig. 2, the control unit 33 is an independent module, and the control unit 33 is electrically connected to the sensor 40 and the stator 31, respectively. The control unit 33 is configured to control the current flowing through the stator 31 after receiving the distance value detected by the position sensor 40, and further control the power of the stator 31, i.e. control the magnetic force between the stator 31 and the rotor 32. Because the rotor 32 is fixedly connected with the impeller 20, the magnetic force control of the stator 31 on the rotor 32 can also play a role in controlling the rotating speed and the suspension position of the impeller 20 by the stator 31.

The control unit 33 includes hardware and software for controlling various aspects of the operation of the motor 30. The control unit 33 may be coupled to the motor 30 through an interface for collecting at least one data of the motor 30. The at least one datum may include measured current flowing through the stator 31, measured data from the sensor 40, motor speed, pressure differential across the pump, flow pulsatility, fluid flow rate, etc.

For example, the sensor 40 may employ a hall plate on which a plurality of hall sensors are provided, which can be used to measure the distance value of the impeller 20 with respect to the first sidewall 11 and transmit the distance value to the control unit 33 through a flexible data line. Specifically, the hall sensor is disposed opposite the path followed by the rotor 32 on the impeller 20. Since the hall sensor outputs a sinusoidal change in signal level representing the magnetic flux intensity when the S pole and N pole of the rotor alternately pass the vicinity of the hall sensor by rotating the impeller 20, the positional relationship between the rotor 32 and the stator 31 can be detected by detecting the time change of the output signal of the hall sensor, and the rotational speed of the impeller 20 in which the current flows through the stator can be calculated.

The high shear forces during rotation of the impeller 20 can damage blood cells, causing more platelets to reside in the secondary flow path, which in turn can coagulate and adhere to the secondary flow path, thereby forming a thrombus.

Based on the above, the application provides a method for detecting the abnormal position, which judges whether an abnormal object exists at present through the operation parameters of the ventricular assist device, and further determines the accurate position of the abnormal object by collecting the operation parameters of the impeller at different axial positions when the abnormal object exists, so that the subsequent flushing operation can be determined according to the accurate position of the abnormal object, the thrombus blocking risk can be reduced under the condition that the complexity of the mechanical design of the pump is not increased or the pump efficiency is reduced, and the blood compatibility is improved.

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

Referring to fig. 5, fig. 5 is a flowchart of an abnormal position detection method according to an embodiment of the present application, which is applied to the ventricular assist device shown in fig. 1-4. As shown in fig. 5, the method includes the following steps.

S510, collecting a plurality of first operation parameter sets of the ventricular assist device in a first time.

During operation of the ventricular assist device 100, the control unit 33 may collect the operation parameters of the ventricular assist device in real time according to the sampling period, and detect whether abnormal objects such as particles or thrombus exist in the secondary flow path of the fluid according to the operation parameters.

Further, to ensure reliability of the operation parameters, the control unit 33 may acquire the first operation parameter set at a first time after determining that the rotational speed of the ventricular assist device 100 is stable. Wherein determining rotational speed stabilization may include: the set rotational speed of the ventricular assist device 100 and the detected actual rotational speed are acquired, and if the absolute value of the difference between the actual rotational speed and the set rotational speed is smaller than a preset value, the current rotational speed of the ventricular assist device 100 is determined to be stable.

Wherein each first set of operating parameters includes a target flow difference, a target power difference, and a target sensor amplitude difference. After the rotational speed of ventricular assist device 100 stabilizes, control unit 33 may acquire flow, power, and amplitude data fed back by sensor 40 for the ventricular assist device at a first time period.

During operation of the ventricular assist device 100 in a patient, the flow rate of pumping through the ventricular assist device 100 is dependent upon the resistance of the ventricular assist device 100 to perform work to pump blood from the left ventricle to the aorta. The amount of work done by ventricular assist device 100 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 ventricular assist device 100 when ventricular assist device 100 is operating in a patient. When the pressure differential in the patient's heart changes, the motor current will also change to keep the rotor speed constant. For example, as the flow rate of blood into the aorta increases (e.g., during systole), the current required by the motor will increase. The change in motor current can therefore help characterize cardiac performance. That is, during operation of ventricular assist device 100, ventricular assist device 100 has a current-flow characteristic, wherein the greater the current, the more ventricular assist device 100 performs, i.e., the greater the pumping flow of ventricular assist device 100.

The current of ventricular assist device 100 may be measured by a phase current detection circuit provided or by any other suitable means, such as a current sensor. The current-flow characteristic curve may be stored in the control unit 33 in advance, and before the ventricular assist device 100 leaves the factory, it may be placed in a test system to test the relationship curve of the pumping flow of the ventricular assist device 100 with the current at different rotational speeds, respectively, so that the current-flow characteristic curve is stored in the control unit 33. The control unit 33 may store the sensed current in real time to calculate the power of the motor 30 and may determine the flow rate of the ventricular assist device based on the current rotational speed and the current-flow characteristic.

The target power difference may be, for example, a difference in power obtained in adjacent sampling periods or a difference in average power obtained in adjacent sampling periods, for example, the control unit 33 obtains the power value of the ventricular assist device 100 from the storage unit every 2 minutes within 6 minutes, and then takes the calculated difference in power obtained in adjacent 2 minutes as the target power difference. Alternatively, the control unit 33 acquires the power value of the ventricular assist device 100 for 6 minutes from the storage unit, then calculates the average value of the power every 2 minutes, and sets the difference between the average values of the power for adjacent 2 minutes as the target power difference. Similarly, the calculation manner of the target flow difference and the target sensor amplitude difference is the same as that of the target power difference, and the description thereof will not be repeated here.

S520, determining whether a target abnormal object exists in a secondary flow channel of the ventricular assist device according to the plurality of first operation parameter sets, wherein the secondary flow channel is a region through which fluid flows from a gap between the impeller and the shell.

During operation of the ventricular assist device 100, a PMC pulsation control function may be activated that periodically and intermittently moves the impeller 20 along the rotational axis 21 within a preset equilibrium range. The control unit 33 may control to move the impeller 20 for at least a few seconds per minute, or to move the impeller 20 based on a triggering event, or to move the impeller 20 based on the impeller 20 exceeding a speed threshold. The speed threshold may be a low speed threshold. The trigger event may be based on a low speed threshold and a time threshold.

Wherein the preset balance range is between the first balance position and the second balance position, and the control unit 33 can control the impeller 20 to repeatedly translate between the first balance position and the second balance position. Further, the impeller 20 spends substantially equal time in the first equilibrium position and the second equilibrium position. Illustratively, the amount of time the impeller spends in the first equilibrium position and the second equilibrium position is inversely proportional to the size of the gap between the impeller 20 and the first and second housings. Thrombosis can be prevented to some extent by controlling the impeller 20 to translate repeatedly within a preset equilibrium range.

Further, the plurality of first operating parameter sets acquired by the control unit 33 are parameters acquired when the ventricular assist device 100 initiates the PMC pulsation control.

Optionally, the determining whether the target abnormality exists in the secondary flow path of the ventricular assist device according to the first operation parameter sets includes: if each target flow difference value in each first operation parameter set is larger than a flow threshold value, each target power difference value is larger than preset power, and each target sensor amplitude value difference value is larger than a first threshold value, determining that the target abnormal object exists in the secondary flow channel; otherwise, determining that the target abnormal object does not exist in the secondary flow channel.

In the present application, the control unit 33 may compare each target flow difference calculated by sampling at a first time with a flow threshold, each target power difference with a preset power, and each target sensor amplitude difference with a first threshold. If all the target flow difference values in the first time are larger than the flow threshold value, all the target power difference values are larger than the preset power, and all the target sensor amplitude value difference values are larger than the first threshold value, judging that the running of the impeller is blocked by the presence of thrombus or particles and other abnormal objects in the current secondary flow channel; otherwise, it is determined that no abnormality exists in the secondary flow path of the ventricular assist device 100.

Specifically, when thrombus or particles exist in the secondary flow passage to prevent the impeller from rotating, the motor 20 needs to overcome more resistance to do work, so that the current flowing through the stator 31 is increased, the flow of the ventricular assist device is increased, the power consumed by the motor is also increased, and the impeller 20 can be repeatedly translated between the first balance position and the second balance position.

Wherein the power threshold may be set to 1W, the flow threshold may be set to 1L/min, the first threshold may be set to 20, 25, 30, 40, etc.

And S530, when the target abnormal object exists in the secondary flow channel, collecting a plurality of second operation parameter sets of the ventricular assist device in a second time, wherein the first time is longer than the second time.

After detecting the presence of an anomaly in the secondary flow path, the control unit 33 detects the position of the thrombus to ensure that the subsequent flushing operation can accurately exclude the anomaly from the ventricular assist device 100.

Wherein each second set of operating parameters includes a detection power and a detection sensor amplitude, the second set of operating parameters having a different acquisition period than the first set of operating parameters. The second operation parameter set is a parameter set collected when the impeller is controlled to suspend at a first position, and the first operation parameter set is a parameter set collected when the impeller is controlled to repeatedly translate in an upward balance position range of the rotating shaft.

Specifically, the control unit 33 may turn off the PMC pulsation control function and then set the levitation position of the impeller 20. After the levitation position of the impeller 20 is set to the first position, the operational parameters are collected during the operation of the ventricular assist device 100 for a second time.

The second set of operating parameters may include a detected power and a detected sensor amplitude sampled at the acquisition cycle, the detected power and the detected sensor amplitude being the power and the sensor amplitude acquired during the second time when the impeller 20 is positioned in the first position and the ventricular assist device 100 is controlled to operate.

Further, the detected power may be the power collected at each sampling period in the second time, or may be the average power in the sampling period. For example, the control unit 33 acquires the power value of the ventricular assist device 100 from the storage unit once every 100ms within 500ms, or the control unit 33 acquires the power value every 100ms from the storage unit, and uses the calculated average power value every 100ms as the detection power. Similarly, the detection sensor amplitude is obtained in the same manner, and is not described in detail herein.

Wherein the first time is longer than the second time, and the sampling period of the first operation parameter set is longer than the sampling period of the second operation parameter set. For example, the first time may be 20min, 16min, 12min, 10min, 8min, 6min, etc., and the second time may be 1s, 0.8s, 0.6s, 0.5s, etc. The sampling period of the first set of operating parameters may be set to 1min, 2min, 4min, etc., and the sampling period of the second set of operating parameters may be set to 50ms, 100ms, 200ms, etc.

S540, determining the position of the target abnormal object according to the plurality of second operation parameter sets.

The target abnormal substance may be thrombus, particles due to friction, tissue, or the like. The location of the target anomaly may be the area of secondary flow path between the impeller 20 and the first housing, where fluid tends to stagnate, causing fluid to stagnate, and the impeller 20 and the second housing.

Optionally, the determining the location of the target anomaly according to the plurality of second operation parameter sets includes: obtaining reference power, wherein the reference power is detection power for controlling the impeller to suspend at a target balance position; if the first difference value is greater than the preset power and the second difference value is smaller than a second threshold value, determining that the target abnormal object is located at the first position, and the volume of the target abnormal object is smaller than or equal to a target value, wherein the first difference value is the difference value between target detection power and the reference power, the target detection power is any detection power in the plurality of second operation parameter sets, the second difference value is the absolute value of the difference value between the first position and the target detection sensor amplitude, and the target detection sensor amplitude is any detection sensor amplitude in the plurality of second operation parameter sets; if the first difference is greater than the preset power, the second difference is greater than the second threshold, and the third difference is less than the second threshold, determining that the target abnormal object is located at the first position, and the volume of the target abnormal object is greater than a target value, wherein the third difference is an absolute value of a difference between the target detection sensor amplitudes of adjacent sampling periods.

In the present application, the control unit 33 suspends the impeller 20 set at the first position, and then determines whether the impeller 20 is suspended to the specified position, i.e., the first position, based on the second operation parameter set. If the impeller 20 can be suspended to the first position, it can be confirmed that no abnormal substance such as particles or thrombus exists in the secondary flow path of the ventricular assist device 100; if the impeller 20 cannot be suspended to the first position, it may be determined that an anomaly is present in the secondary flow path of the ventricular assist device 100, and further the magnitude of the anomaly may be determined based on the second set of operating parameters.

Wherein the first position is a position of the impeller at a target distance from the first housing or the second housing. The target distance is in the range of 0.02mm-0.05mm, i.e. the distance between the impeller 20 and the second surface 23 and the first side wall 11 is in the range of 0.02mm-0.05mm, or the distance between the impeller 20 and the first surface 22 and the second side wall 12 is in the range of 0.02mm-0.05 mm.

It should be noted that the first position is not within the preset balance range, and the target balance position is within the preset balance range. The preset equilibrium range may be set to 0.05mm-0.5mm, i.e. the distance between the second surface 23 and the first side wall 11 or the first surface 22 and the second side wall 12 is in the range of 0.05mm-0.5 mm.

The control unit 33 obtains the reference power specifically as follows: after turning off the PMC pulsation control function, the control unit 33 controls the levitation position of the impeller 20 at the target equilibrium position, records the current rotational speed of the ventricular assist device 100, and calculates the average amplitude of the sensor 40 and the average power of the ventricular assist device per a preset period, which may be set to 50ms, 100ms, 200ms, etc. If the difference between the average amplitude of the ith preset period and the average amplitude of the ith preset period is smaller than the second threshold value, the average power recorded in the ith preset period is used as the reference power.

In particular, the target equilibrium position may be an intermediate position between the first equilibrium position and the second equilibrium position, i.e. the target equilibrium position is equidistant from the first equilibrium position and the second equilibrium position. The reference power is the impeller 20 in the neutral position of the chamber 10.

Illustratively, the first position is a position of the impeller 20 at a target distance from the first housing, as shown in FIG. 3. At this time, the gap between the impeller 20 and the first casing is reduced, and the gap between the impeller 20 and the second casing is increased. When an anomaly exists in the secondary flow channel, the power of the ventricular assist device is increased, so that if the difference between the power at the first position and the reference power is detected to be larger than the preset power, namely, the difference between the target detection power and the reference power is detected to be larger than the preset power, the anomaly can be judged to exist in the secondary flow channel; if the difference between the target detection power and the reference power is smaller than the preset power, it can be judged that no abnormal object exists in the secondary flow channel.

When an abnormal object exists in the secondary flow passage, the volume of the abnormal object can be further judged according to the suspension position of the impeller. The volume can be quantified based on the difference between the current sensor detected impeller levitation position and the set impeller levitation position. The method comprises the following steps: if the difference between the position of the impeller 20 detected by the current sensor 40 and the first position of the first housing is smaller than the second threshold, that is, the detected impeller suspension position and the set impeller suspension position have smaller differences, the volume of the anomaly is smaller. If the difference between the detected position of the impeller 20 relative to the first housing and the first position is greater than the second threshold, and the absolute value of the difference between the target detection sensor amplitude of the ith sampling period and the target detection sensor amplitude of the (i-1) th sampling period is smaller than the second threshold, that is, the detected impeller suspension position and the set impeller suspension position have a larger difference at this time, and the impeller suspension position in the adjacent sampling period has a smaller change, the volume of the anomaly is determined to be larger, so that the impeller suspension position always cannot reach the set first position.

Similarly, the first position is a position where the impeller 20 is at a target distance from the second housing, as shown in fig. 4. At this time, the gap between the impeller 20 and the second casing is reduced, and the gap between the impeller 20 and the first casing is increased. The control unit 33 may determine whether an anomaly exists in the secondary flowpath according to a difference between the target detection power and the reference power. When an abnormal object exists in the secondary flow passage, the size of the abnormal object is determined by comparing the difference value between the impeller suspension position detected by the sensor and the set impeller suspension position, namely, according to the difference value between the detected position of the impeller 20 relative to the first shell and the first position. The comparison method can refer to the above, and is not repeated here.

It should be noted that, the second threshold may be set according to an actual application scenario, and the value of the second threshold depends on the tolerance of the user to the size of the anomaly. The larger the second threshold, the larger the anomaly volume and the higher the tolerance of the user to the anomaly.

After determining that an anomaly is present and determining the exact location of the anomaly, the control unit 33 may move the impeller 20 within the chamber 10 in the direction of the axis of rotation 21 to increase the clearance between the impeller 20 and the first housing or the second housing, and/or increase the rotational speed of the ventricular assist device, increase the flush rate to clear the anomaly from the secondary flow path, and reduce or prevent the anomaly from jeopardizing the ventricular assist device 100 and the user.

Optionally, the method further comprises: if the target abnormal object is determined to be positioned at the first position, controlling the impeller to move from the first position to a second position, wherein the second position is different from the first position; and controlling the rotating speed of the ventricular assist device to flush the target abnormal object so as to move the target abnormal object out of the ventricular assist device.

The first position is a position of the impeller 20 at a target distance from the first housing, and the second position is a position of the impeller 20 at a target distance from the second housing. When an anomaly is located in the gap between the impeller 20 and the first housing, the control unit 33 may move the impeller 20 from the first position to the second position to increase the gap between the impeller 20 and the first housing.

The first position is a position of the impeller 20 at a target distance from the second housing, and the second position is a position of the impeller 20 at a target distance from the first housing. When an anomaly is located in the gap between the impeller 20 and the second housing, the control unit 33 may move the impeller 20 from the first position to the second position to increase the gap between the impeller 20 and the second housing.

Optionally, the controlling the rotational speed of the ventricular assist device to flush the target anomaly includes: increasing the rotational speed of the ventricular assist device to a first rotational speed for a first duration; reducing the ventricular assist device from a first rotational speed to a second rotational speed for the first period of time; repeating the steps m times, wherein m is a positive integer; setting the rotational speed of the ventricular assist device to a target rotational speed that is a rotational speed at which the impeller is controlled to float at the target equilibrium position.

The control unit 33 moves the impeller 20 from the first position to the second position according to the position of the anomaly, and then increases the rotational speed of the ventricular assist 100 to wash the anomaly. The method comprises the following steps: the rotational speed of the ventricular assist device 100 is accelerated to the first rotational speed at a first acceleration and the anomaly is flushed for a first period of time. Then, at the reduced speed, the ventricular assist device is reduced to a second rotational speed at a second acceleration for a second duration. The above cycle is repeated m times with this as one cycle, and intermittent flushing of abnormal objects is realized. After the flushing is completed, the rotation speed of the ventricular assist device is reset to the target rotation speed, and the ventricular assist device is detected in the first time according to the method set forth above, if an abnormal object can still be detected, the control unit 33 can control to alarm, so as to prompt that the abnormal object exists in the current flow channel and cannot be flushed. If no anomaly is detected within the first time, the control unit 33 may activate the PMC pulsation control function and the ventricular assist device may operate normally.

For example, after the control unit 33 moves the impeller 20 from the first position to the second position, the first step is: the speed of the ventricular assist device 100 was set to 4300rpm, after which the rotational speed of the ventricular assist device 100 was accelerated to 4300rpm at an acceleration of 300, and the rotational speed of the ventricular assist device was 4300rpm for 2s. And a second step of: the rotational speed of the ventricular assist device was set to 2200rpm, and the rotational speed of the ventricular assist device 100 was decelerated to 2200rpm with the acceleration 300, and maintained for 2S. After repeating the first and second steps 5 times, the flushing operation is ended.

The number m of flushing repetition times can be 5, 8, 10 and the like, and specific values can be determined according to actual users and application scenes.

In the early stage of thrombus formation, the thrombus is flushed out through flushing operation, so that the problem that the ventricular assist device 100 cannot operate due to the fact that the thrombus is further generated to be large to block the impeller can be prevented, and the service life of the ventricular assist device 100 is prolonged.

It can be seen that the present application proposes an abnormal position detection method, which collects a plurality of first operation parameter sets of a ventricular assist device in a first time; determining whether a target anomaly is present in a secondary flow path of the ventricular assist device, the secondary flow path being a region through which fluid flows from a gap between the impeller and the housing, according to the plurality of first operating parameter sets; collecting a plurality of second operation parameter sets of the ventricular assist device in a second time when the target abnormal object exists in the secondary flow channel; and determining the position of the target abnormal object according to the plurality of second operation parameter sets. According to the method, whether abnormal objects such as particles or thrombus exist between the impeller and the shell gap or not is judged through the operation parameters of the ventricular assist device, and then the specific position of the abnormal object in the gap is determined when the abnormal objects exist, so that the abnormal objects can be accurately positioned under the condition that the complexity of the mechanical design of the pump is not increased or the pump efficiency is reduced, and the follow-up accurate flushing of the abnormal objects such as the particles or thrombus is facilitated.

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 elements and algorithm steps described in connection with the embodiments disclosed herein may be embodied as hardware or a combination 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.

By way of example, the present application provides a control unit comprising a controller having one or more processors configured to: acquiring a plurality of first operating parameter sets of the ventricular assist device over a first time period; determining whether a target anomaly is present in a secondary flow path of the ventricular assist device according to the plurality of first operating parameter sets, the secondary flow path being a region through which fluid flows from a gap between the impeller and the housing; collecting a plurality of second operating parameter sets of the ventricular assist device during a second time when the target anomaly exists in the secondary flow path, wherein the first time is longer than the second time; and determining the position of the target abnormal object according to the plurality of second operation parameter sets.

Optionally, each first set of operating parameters includes a target flow difference, a target power difference, and a target sensor amplitude difference.

Optionally, in determining whether a target anomaly is present in the secondary flow path of the ventricular assist device according to the plurality of first operating parameter sets, the control unit is specifically configured to: if each target flow difference value in each first operation parameter set is larger than a flow threshold value, each detection power difference is larger than preset power, and each target sensor amplitude difference value is larger than a first threshold value, determining that the target abnormal object exists in the secondary flow channel; otherwise, determining that the target abnormal object does not exist in the secondary flow channel.

Optionally, each second operating parameter set includes a detection power and a detection sensor amplitude, and a collection period of the second operating parameter set is different from a collection period of the first operating parameter set; the second operation parameter set is a parameter set collected when the impeller is controlled to suspend at a first position, and the first operation parameter set is a parameter set collected when the impeller is controlled to repeatedly translate in an upward balance position range of the rotating shaft.

Optionally, in determining the position of the target anomaly according to the plurality of second operating parameter sets, the control unit is specifically configured to: obtaining reference power, wherein the reference power is detection power for controlling the impeller to suspend at a target balance position; if the first difference value is greater than the preset power and the second difference value is smaller than a second threshold value, determining that the target abnormal object is located at the first position, and the volume of the target abnormal object is smaller than or equal to a target value, wherein the first difference value is the difference value between target detection power and the reference power, the target detection power is any detection power in the plurality of second operation parameter sets, the second difference value is the absolute value of the difference value between the first position and the target detection sensor amplitude, and the target detection sensor amplitude is any detection sensor amplitude in the plurality of second operation parameter sets; if the first difference is greater than the preset power, the second difference is greater than the second threshold, and the third difference is less than the second threshold, determining that the target abnormal object is located at the first position, and the volume of the target abnormal object is greater than a target value, wherein the third difference is an absolute value of a difference between the target detection sensor amplitudes of adjacent sampling periods.

Optionally, the first position is a position of the impeller at a target distance from the first housing or the second housing.

Optionally, the target distance is in the range of 0.02mm-0.05 mm.

Optionally, the control unit is further configured to: if the target abnormal object is determined to be positioned at the first position, controlling the impeller to move from the first position to a second position, wherein the second position is different from the first position; and controlling the rotating speed of the ventricular assist device to flush the target abnormal object so as to move the target abnormal object out of the ventricular assist device.

Optionally, in controlling the flushing of the target anomaly by the rotational speed of the ventricular assist device, the control unit is specifically configured to: increasing the rotational speed of the ventricular assist device to a first rotational speed for a first duration; reducing the ventricular assist device from a first rotational speed to a second rotational speed for the first period of time; repeating the steps m times, wherein m is a positive integer; setting the rotational speed of the ventricular assist device to a target rotational speed that is a rotational speed at which the impeller is controlled to float at the target equilibrium position.

By way of example, the present application also provides a ventricular assist device comprising:

a housing;

a sensor for detecting a distance between the impeller and the housing;

The present application also provides, for example, a medical device comprising the control unit or the ventricular assist device described above.

The control circuit of each scheme has 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 the embodiments of the present application, the control circuit may also be a chip or a chip system, for example: system on chip (SoC).

Referring to fig. 6, fig. 6 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:

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.

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

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 some 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 expressed as a series of action combinations, but it should be understood by those skilled in the art that the present application is not limited by the order of actions described, as some steps may be performed in other order or simultaneously 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 in 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.

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 in part or all of the technical solution contributing to the prior art or in the form of a software product stored in a memory, comprising 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 methods of the various 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 present application, wherein specific examples are provided herein to illustrate the principles and embodiments of the present application, the above examples being provided solely to assist in the understanding of the methods of the present application and the core ideas thereof; meanwhile, as those skilled in the art will have modifications 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. An abnormal position detection method is characterized by being applied to a ventricular assist device, wherein the ventricular assist device comprises a shell, an impeller which is arranged in the shell and rotates in a suspending way, and a sensor for detecting the distance between the impeller and the shell; the method comprises the following steps:

2. The method of claim 1, wherein each first set of operating parameters includes a target flow difference value, a target power difference value, and a target sensor amplitude difference value;

the determining whether a target anomaly is present in a secondary flow path of the ventricular assist device according to the plurality of first operating parameter sets includes:

if each target flow difference value in each first operation parameter set is larger than a flow threshold value, each target power difference value is larger than preset power, and each target sensor amplitude value difference value is larger than a first threshold value, determining that the target abnormal object exists in the secondary flow channel;

otherwise, determining that the target abnormal object does not exist in the secondary flow channel.

3. The method of claim 2, wherein each second set of operating parameters includes a detection power and a detection sensor amplitude, the second set of operating parameters having a different acquisition period than the first set of operating parameters;

the second operation parameter set is a parameter set collected when the impeller is controlled to suspend at a first position, and the first operation parameter set is a parameter set collected when the impeller is controlled to repeatedly translate in an upward balance position range of the rotating shaft.

4. A method according to claim 3, wherein said determining the location of the target anomaly from the plurality of second sets of operating parameters comprises:

obtaining reference power, wherein the reference power is detection power for controlling the impeller to suspend at a target balance position;

if the first difference value is greater than the preset power and the second difference value is smaller than a second threshold value, determining that the target abnormal object is located at the first position, and the volume of the target abnormal object is smaller than or equal to a target value, wherein the first difference value is the difference value between target detection power and the reference power, the target detection power is any detection power in the plurality of second operation parameter sets, the second difference value is the absolute value of the difference value between the first position and the target detection sensor amplitude, and the target detection sensor amplitude is any detection sensor amplitude in the plurality of second operation parameter sets;

If the first difference is greater than the preset power, the second difference is greater than the second threshold, and the third difference is less than the second threshold, determining that the target abnormal object is located at the first position, and the volume of the target abnormal object is greater than a target value, wherein the third difference is an absolute value of a difference between the target detection sensor amplitudes of adjacent sampling periods.

5. The method of claim 4, wherein the housing has a first side wall and a second side wall opposite the first side wall, the second side wall having a fluid inlet opening therein;

the first position is a position of the impeller at a target distance from the first sidewall or the second sidewall.

6. The method of claim 5, wherein the target distance is in the range of 0.02mm-0.05 mm.

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

if the target abnormal object is determined to be positioned at the first position, controlling the impeller to move from the first position to a second position, wherein the second position is different from the first position;

and controlling the rotating speed of the ventricular assist device to flush the target abnormal object so as to move the target abnormal object out of the ventricular assist device.

8. The method of claim 7, wherein said controlling the rotational speed of the ventricular assist device to flush the target anomaly comprises:

increasing the rotational speed of the ventricular assist device to a first rotational speed for a first duration;

reducing the ventricular assist device from a first rotational speed to a second rotational speed for the first period of time;

repeating the steps m times, wherein m is a positive integer;

setting the rotational speed of the ventricular assist device to a target rotational speed that is a rotational speed at which the impeller is controlled to float at the target equilibrium position.

9. The method of claim 1, wherein the housing has a first side wall and a second side wall opposite the first side wall, the second side wall having a fluid inlet opening therein; the impeller is located between the first side wall and the second side wall, the impeller is provided with a first surface, a second surface, a central hole and a flow channel, the first surface is opposite to the second side wall, the second surface is opposite to the first side wall, the central hole penetrates through the first surface and the second surface, the central hole is opposite to the fluid inlet, the flow channel is arranged between the first surface and the second surface, the flow channel is communicated with the central hole, and a secondary flow channel is formed between the first surface and the second side wall, and between the second surface and the first side wall.

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

collecting a plurality of first operating parameter sets of the ventricular assist device at a first time;

11. A ventricular assist device, the ventricular assist device comprising:

a housing;

a sensor for detecting a distance between the impeller and the housing;

12. 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 1-9.

13. 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 1-9.