Pressure control method and device based on infusion device

Abstract

This application proposes a pressure control method and apparatus based on an infusion device. The method includes: acquiring n first voltages and n second voltages corresponding to n preset pressures in the infusion tube, wherein the n preset pressures are arranged in ascending order; determining a target mapping relationship between voltage and pressure based on the n preset pressures, n first voltages, and n second voltages; acquiring a target voltage of the fluid in the infusion tube detected by a pressure sensor when the pump assembly is working; determining a target pressure corresponding to the target voltage based on the target mapping relationship; and adjusting the rotational speed of the pump assembly according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range. This application fits the mapping relationship between pressure and voltage in the infusion tube during both increasing and decreasing pressure, making it more consistent with the dynamic changes of the infusion tube during actual operation, reducing the mapping error between voltage and pressure, and improving the accuracy of pressure detection.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a pressure control method and device based on an infusion device. Background Technology

[0002] A ventricular assist system mainly consists of an interventional ventricular assist device (VAD), a controller, and an infusion device. The interventional ventricular assist device (VAD) is primarily used for protection during high-risk percutaneous coronary intervention (PCI) procedures. The infusion device maintains a voltage barrier between the blood and the motor, using a voltage generated by a flushing fluid flowing in the opposite direction to the blood flow to isolate the blood from the motor and prevent blood from entering the motor.

[0003] In the clinical application of interventional VAD (Ventricular Assist Device) for treatment, it is required to detect the voltage in the infusion line as accurately as possible in order to provide stable and reliable back pressure and flushing fluid for the VAD. Summary of the Invention

[0004] This application provides a pressure control method and apparatus based on an infusion device, which can increase the detection accuracy of the pressure inside the flushing tube, thereby improving the reliability of pressure control.

[0005] In a first aspect, embodiments of this application provide a pressure control method based on an infusion device, the infusion device comprising an infusion tube for conveying fluid, a pressure sensor disposed on the outer surface of the infusion tube, and a pump assembly for driving fluid flow; the method includes:

[0006] Obtain n first voltages and n second voltages corresponding to n preset pressures of the infusion tube. The n preset pressures are arranged in ascending order. The first voltage is the voltage detected by the pressure sensor during the process of pressure increase in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the process of pressure decrease in the infusion tube. The n is an integer greater than 1.

[0007] The target mapping relationship between voltage and pressure is determined based on the n preset pressures, the n first voltages, and the n second voltages;

[0008] When the pump assembly is operating, the target voltage of the fluid in the infusion tube detected by the pressure sensor is acquired;

[0009] The target voltage is determined based on the target mapping relationship;

[0010] The pump assembly speed is adjusted according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range.

[0011] Secondly, an embodiment of this application provides an infusion device, which includes an infusion tube for conveying fluid, a pressure sensor disposed on the outer surface of the infusion tube, a pump assembly for driving fluid flow, and a control circuit electrically connected to the pump assembly; the control circuit is used for:

[0012] Obtain n first voltages and n second voltages corresponding to n preset pressures of the infusion tube. The n preset pressures are arranged in ascending order. The first voltage is the voltage detected by the pressure sensor during the process of pressure increase in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the process of pressure decrease in the infusion tube. The n is an integer greater than 1.

[0013] The target mapping relationship between voltage and pressure is determined based on the n preset pressures, the n first voltages, and the n second voltages;

[0014] When the pump assembly is operating, the target voltage of the fluid in the infusion tube detected by the pressure sensor is acquired;

[0015] The target voltage is determined based on the target mapping relationship;

[0016] The pump assembly speed is adjusted according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range.

[0017] Thirdly, embodiments of this application provide a ventricular assist system, the ventricular assist system comprising:

[0018] Ventricular assist device;

[0019] An infusion device mechanically connected to the ventricular assist device, the infusion device comprising an infusion tubing for delivering fluid, a pressure sensor disposed on the outer surface of the infusion tubing, and a pump assembly for driving fluid flow;

[0020] And a control device communicatively connected to the ventricular assist device and the infusion device, the control device being used for:

[0021] Obtain n first voltages and n second voltages corresponding to n preset pressures of the infusion tube. The n preset pressures are arranged in ascending order. The first voltage is the voltage detected by the pressure sensor during the process of pressure increase in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the process of pressure decrease in the infusion tube. The n is an integer greater than 1.

[0022] The target mapping relationship between voltage and pressure is determined based on the n preset pressures, the n first voltages, and the n second voltages;

[0023] When the pump assembly is operating, the target voltage of the fluid in the infusion tube detected by the pressure sensor is acquired;

[0024] The target voltage is determined based on the target mapping relationship;

[0025] The pump assembly speed is adjusted according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range.

[0026] Fourthly, embodiments of this application provide a medical device, the medical device including a processor, a memory, a communication interface, and one or more programs, the one or more programs being stored in the memory and configured to be executed by the processor, the programs including instructions for performing some or all of the steps described in the method described in the first aspect above.

[0027] Fifthly, embodiments of this application provide a computer-readable storage medium storing a computer program for electronic data interchange, wherein the computer program causes a computer to perform some or all of the steps described in the method described in the first aspect above.

[0028] Sixthly, embodiments of this application provide a computer program product, wherein the computer program product includes 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 described in the first aspect of embodiments of this application. The computer program product may be a software installation package.

[0029] The technical solution provided in this application acquires n first voltages and n second voltages corresponding to n preset pressures in the infusion tube, with the n preset pressures arranged in ascending order; determines a target mapping relationship between voltage and pressure based on the n preset pressures, n first voltages, and n second voltages; acquires the target voltage of the fluid in the infusion tube detected by the pressure sensor when the pump assembly is working; determines the target pressure corresponding to the target voltage based on the target mapping relationship; and adjusts the speed of the pump assembly according to the target pressure to stabilize the pressure in the infusion tube within the preset pressure range. This application measures the first and second voltages corresponding to the preset pressures during the increase and decrease of pressure in the infusion tube, respectively. By fitting the mapping relationship between pressure and voltage in the infusion tube using the first and second voltages, the mapping relationship better reflects the dynamic changes of the infusion tube during actual operation, reducing the mapping error between voltage and pressure, improving the accuracy of pressure detection, and thus improving the reliability of pressure control. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of an infusion device with the pump door closed, provided in an embodiment of this application;

[0032] Figure 2 This is a schematic diagram of the structure of an infusion device provided in this application when the pump door is omitted;

[0033] Figure 3 This is a schematic diagram of the structure of an infusion tube and pump door provided in an embodiment of this application;

[0034] Figure 4 This is a structural block diagram of an interventional ventricular assist system provided in an embodiment of this application;

[0035] Figure 5 This is a schematic flowchart of a pressure control method based on an infusion device provided in an embodiment of this application;

[0036] Figure 6 This is a schematic diagram of the mapping relationship between the pressure inside an infusion tube and the output voltage of a pressure sensor, provided in an embodiment of this application.

[0037] Figure 7 This is a schematic diagram of the structure of a medical device provided in an embodiment of this application. Detailed Implementation

[0038] To help those skilled in the art better understand the technical solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the description of the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0039] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, software, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but also includes steps or units not listed, or other steps or units inherent to such processes, methods, products, or apparatus.

[0040] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0041] In this application, as Figures 1-3 As shown, the infusion device 10 includes a base 200 and a pump door 120. A pump assembly and an infusion tube 400 connected to the pump assembly are installed inside the base 200. The pump door 120 is movably connected to the base 200, for example, by rotation. By rotating the pump door 120 relative to the base 200, the pump door 120 and the base 200 can be closed or opened.

[0042] Specifically, the infusion tubing 400 is at least partially located between the pump assembly and the pump gate 120. Specifically, the infusion tubing 400 has a first section 410 located between the pump assembly and the pump gate 120; when the pump gate 120 closes the base 200, the pump gate 120 and the pump assembly together compress the first section 410 in the infusion tubing 400.

[0043] For example, the pump assembly includes a peristaltic unit 140, and the base 200 is provided with a receiving cavity 220. When the pump door 120 closes or opens the base 200, it can be understood that the pump door 120 closes or opens the receiving cavity 220, and the peristaltic unit 140 can be at least partially accommodated in the receiving cavity 220. In addition, a clearance channel can be provided in the receiving cavity 220 for the infusion tube 400 to pass through.

[0044] In some embodiments, the peristaltic unit 140 is disposed on the base 200 and corresponds to the first segment 410 of the infusion tube 400. The peristaltic unit 140 has a plurality of peristaltic plates 141, which are arranged sequentially along the extension direction of the infusion tube 400. The peristaltic plates 141 and the pump gate 120 are distributed on two opposite sides of the radial direction of the infusion tube 400 (specifically the first segment 410) and can work together on the infusion tube 400.

[0045] In one embodiment, the pump assembly further includes a rotating shaft with multiple cams mounted on it. These cams are sequentially mounted axially on the shaft, and each cam is fitted with a peristaltic vane 141. The cams on the shaft cause the peristaltic vane 141 to move in a wave-like motion according to a certain timing sequence. Each peristaltic vane 141 can move back and forth radially along the infusion tube 400. When the peristaltic vane 141 moves towards the infusion tube 400, it can work together with the pump door 120 to squeeze the infusion tube 400, so that the fluid in the infusion tube 400 is subjected to a continuous thrust related to the movement sequence of the peristaltic vane 141, thereby causing the fluid to flow and achieving the effect of fluid delivery.

[0046] When the pump door 120 closes the base 200, the first pipe section 410 is located between the peristaltic unit 140 and the pump door 120. When the peristaltic unit 140 starts working, it moves towards the pump door 120, thereby working together with the pump door 120 to squeeze the infusion tube 400, squeezing out the liquid in the infusion tube 400, and finally realizing the pumping function of the infusion device 10.

[0047] The infusion tubing 400 also includes a second tubing segment 420 communicating with the first tubing segment 410. The infusion device 10 also includes a pressure sensor 130, which is in contact with the second tubing segment 420 in the infusion tubing 400. In other words, the pressure sensor 130 is disposed on the outer wall of the infusion tubing 400 (specifically the second tubing segment 420) to detect the voltage of the second tubing segment 420. The second tubing segment 420 is a section of the infusion tubing 400 that is not subjected to compression by the pump door 120 and / or the peristaltic unit 140.

[0048] In one embodiment, the base 200 is provided with an installation channel 330 for the infusion tube 400 to pass through, and the pressure sensor 130 is at least partially located within the installation channel 330. A cover plate 300 is installed on the base 200, covering a portion of the installation channel 330. A second tube segment 420 is installed within the installation channel 330, with the position of the second tube segment 420 corresponding to the position of the cover plate 300. The position of the pressure sensor 130 also corresponds to the position of the cover plate 300, and the pressure sensor 130 is located between the cover plate 300 and the second tube segment 420. When the infusion tube 400 is installed in the installation channel 330, the cover plate 300 brings the pressure sensor 130 into contact with the second tube segment 420 in the infusion tube 400, enabling the pressure sensor 130 to detect the voltage of the second tube segment 420.

[0049] For example, the infusion device 10 also includes a control circuit electrically connected to the pump assembly, which controls the fluid pressure and flow rate in the infusion tubing 400 by controlling the operating speed of the pump assembly. The faster the shaft rotates, the faster the fluid is delivered.

[0050] In some scenarios, such as Figure 4 As shown, in an interventional ventricular assist system, the system includes a ventricular assist device 30, a control device 20, and an infusion device 10. The ventricular assist device 30 is implanted in the patient's body, crossing the aortic valve of the heart, with its proximal end located within the aorta and its distal end within the left ventricle. This allows the ventricular assist device 30 to pump blood from the left ventricle into the aorta, providing partial or complete assistance to the cardiac circulatory system. The control device 20 and the infusion device 10 are located externally. The control device 20 is used to control and display data on the ventricular assist device 30 and the infusion device 10, as well as perform functions such as fault detection alarms and data recording.

[0051] For example, the control circuit in the infusion device 10 can be integrated into the infusion device 10 or into the control device 20. This application embodiment does not limit this.

[0052] The infusion device 10 is connected to the ventricular assist device 30. One end of the infusion tubing 400 can be connected to an infusion bottle or bag, which can provide flushing solutions such as saline or heparin. The other end of the infusion tubing 400 can be connected to the motor of the ventricular assist device 30, so that the flushing solution delivered by the infusion tubing 400 enters the motor of the ventricular assist device 30 and then flows into the aorta, fluidly sealing the motor and preventing blood from entering the motor through gaps, which could cause motor malfunction.

[0053] To ensure a proper fluid seal, the voltage at the final outlet of the infusion device 10 delivering the flushing fluid must consistently be greater than or equal to the blood flow voltage. The control circuit estimates the current pressure within the infusion tubing 400 based on the voltage value detected by the pressure sensor 130, and then controls the pump assembly's rotation speed based on this estimated pressure to accelerate the peristaltic plate 141 and increase the fluid flow rate within the infusion tubing 400. However, since the infusion devices 10 in current ventricular assist systems are primarily assembled manually, assembly and manufacturing issues result in a certain deviation in the mapping relationship between the voltage detected by the pressure sensor and the pressure in each infusion device 10. This deviation affects the accuracy of pressure control within the infusion device, thus impacting the precision requirements of medical equipment such as ventricular assist systems.

[0054] Based on this, this application proposes a pressure control method based on an infusion device. The method measures a first voltage and a second voltage corresponding to a preset pressure during the process of increasing and decreasing the pressure in the infusion tube. By fitting the mapping relationship between the pressure and voltage in the infusion tube using the first voltage and the second voltage, the mapping relationship is made more consistent with the dynamic changes of the infusion tube during actual operation, reducing the mapping error between voltage and pressure, improving the accuracy of pressure detection, and thus improving the reliability of pressure control.

[0055] Based on the above description, this application will now be described from the perspective of method examples.

[0056] Please see Figure 5 , Figure 5 This application provides a schematic flowchart of a pressure control method based on an infusion device, applicable to, for example... Figures 1-4 The infusion device 10 is shown. (Example) Figure 5 As shown, the method includes the following steps.

[0057] S510. Obtain n first voltages and n second voltages corresponding to n preset pressures of the infusion tube. The n preset pressures are arranged in ascending order. The first voltage is the voltage detected by the pressure sensor during the pressure increase process in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the pressure decrease process in the infusion tube. The n is an integer greater than 1.

[0058] Before the infusion device 10 leaves the factory or before the ventricular assist system is started, the mapping relationship between the voltage value detected by the pressure sensor 130 in the infusion device 10 and the pressure inside the infusion tube 400 can be determined. Then, the voltage value detected by the pressure sensor 130 can be adjusted by adjusting the speed of the pump assembly, so that the pressure inside the infusion tube 400 is kept within a stable working pressure range, thereby maintaining the safe operation of the ventricular assist device 30.

[0059] Optionally, obtaining n first voltages and n second voltages corresponding to n preset pressures of the infusion tube includes: sequentially increasing the pressure in the infusion tube to the n preset pressures until a preset alarm pressure is reached; recording the first voltages measured by the pressure sensor after the pressure in the infusion tube reaches the preset pressure at a first time; sequentially decreasing the pressure in the infusion tube from the preset alarm pressure to the n preset pressure points, and recording the second voltages measured by the pressure sensor after the pressure in the infusion tube reaches the preset pressure at a first time.

[0060] When determining the mapping relationship between the voltage value detected by the pressure sensor 130 in the infusion device 10 and the pressure inside the infusion tube 400, a pressure detector can be set up to detect the pressure inside the infusion tube 400. The pressure detector is an automatically calibrated instrument with accurate pressure measurement, which can detect the pressure inside the infusion tube 400 in real time and feed the detected pressure inside the infusion tube 400 back to the control unit in real time. The pressure sensor 130 in the infusion device 10 can detect the pressure value inside the infusion tube 400 in real time and feed the output voltage value back to the control circuit in real time.

[0061] Specifically, the control circuit can set multiple preset pressures for the calibration voltage points, arranged in ascending order. The control circuit can increase the pressure within the infusion tubing 400 by increasing the pump assembly's rotational speed. The pressure detector and pressure sensor 130 can feed back the detected pressure and voltage values ​​within the infusion tubing 400 to the control circuit in real time. When the control circuit detects that the current pressure within the infusion tubing 400 has reached the preset pressure for the calibration voltage point, it can immediately read and store the voltage value measured by the pressure sensor 130, i.e., the first voltage. Following this method, the control circuit gradually increases the pressure within the infusion tubing 400 until it reaches the preset alarm pressure. Then, the control circuit reduces the pump assembly's rotational speed to gradually decrease the pressure within the infusion tubing 400 from the preset alarm pressure. During the pressure reduction process within the infusion tubing 400, if the pressure reaches the preset pressure required for calibration, the control circuit reads and stores the voltage value measured by the pressure sensor 130 after a certain time, i.e., the second voltage. Following this method, the control circuit gradually reduces the pressure within the infusion tubing 400 until the initial pressure is reached. Thus, n first voltages and n second voltages corresponding to n preset pressures during the pressure increase and decrease processes of the infusion tubing 400 can be obtained.

[0062] The first time interval can be set to 5s, 10s, 15s, etc. Since the fluid flow rate in the infusion tube 400 continues to increase even when the fluid pressure reaches the preset pressure, the fluid pressure in the infusion tube 400 will continue to increase for a period of time. During this time, the voltage value measured by the pressure sensor may have some error compared to the actual value. Therefore, to avoid this problem, the control unit can wait for the first time interval when the pressure in the infusion tube 400 reaches the preset pressure, and maintain the pressure in the infusion tube 400 near the preset pressure during this first time interval. The control unit will then read the voltage value output by the pressure sensor 130 when the pressure in the infusion tube 400 stabilizes at the preset pressure. For example, the control circuit can calculate the average value of the voltage value output by the pressure sensor 130 during the first time interval when the pressure in the infusion tube 400 reaches the preset pressure, and use this average voltage value as the voltage value corresponding to the preset pressure.

[0063] This application uses a pressure detector and a pressure sensor 130 to collect pressure and voltage values ​​in the infusion tube 400 during the pressure increase and decrease processes, respectively. Then, it performs curve fitting on the collected pressure and voltage values ​​to obtain the mapping relationship between the voltage value output by the pressure sensor in the infusion device and the pressure in the infusion tube 400. Thus, when the ventricular assist system is running, the control circuit controls the pressure and fluid flow rate in the infusion tube 400 according to the voltage value fed back by the pressure sensor 130.

[0064] The infusion device 10 has a pressure increase and a pressure decrease process during actual operation. Therefore, this application uses the voltage value during the pressure increase process and the voltage value during the pressure decrease process corresponding to the same pressure point to determine the mapping relationship between voltage and pressure, so that the pressure value mapped from the voltage is more accurate when the ventricular assist system is running.

[0065] For example, the method further includes: obtaining the working pressure range of the infusion device; determining the acquisition range of the preset pressure based on the working pressure range; and determining the interval between the preset pressures based on the preset pressure accuracy.

[0066] In this application, in order to reduce the time required to determine the mapping relationship between voltage and pressure within the infusion tube 400 and to increase the accuracy of the mapping relationship, the control circuit can select the value of the preset pressure and the interval between adjacent preset pressures based on the working pressure range of the infusion device 100.

[0067] Specifically, the control circuit acquires the pressure range required to be maintained by the infusion device 10 during normal operation of the ventricular assist device 30, and determines the preset pressure acquisition range based on this pressure range. For example, the preset pressure acquisition range can be set to the operating pressure range of the infusion device 10. In another example, the preset pressure acquisition range can be set to be greater than the operating pressure range of the infusion device 10; for example, the minimum value of the preset pressure acquisition range can be 0.8 times the minimum value of the operating pressure range, and the maximum value can be the preset alarm pressure.

[0068] In one example, the operating pressure range of the infusion device 10 can be 450 mmHg to 600 mmHg.

[0069] In another example, the operating pressure range of the infusion device 10 can be 700 mmHg to 1000 mmHg.

[0070] To ensure that the mapping error between the voltage value detected by the pressure sensor 130 and the pressure meets the preset error, the control circuit can determine the interval between preset pressures based on the preset pressure accuracy, and thus determine the value of n. The smaller the preset pressure accuracy, i.e., the smaller the error, the smaller the interval between preset pressure values ​​and the larger the value of n.

[0071] In this application, the required pressure accuracy can be determined according to the application scenario of the infusion device 10, the sampling range of the preset pressure can be determined according to the working pressure in the infusion tube 400, and the sampling frequency of the preset pressure can be determined according to the pressure accuracy, so that the infusion device 10 can meet different application requirements while reducing the detection error of the pressure sensor 130.

[0072] S520. Determine the target mapping relationship between voltage and pressure based on the n preset pressures, the n first voltages, and the n second voltages.

[0073] In this application, the control unit can use the least squares method to perform multiple polynomial curve fittings on n preset pressures, n first voltages and n second voltages to obtain the mapping relationship between the pressure inside the infusion tube 400 and the output voltage value of the pressure sensor 130.

[0074] Optionally, determining the target mapping relationship between voltage and pressure based on the n preset pressures, the n first voltages, and the n second voltages includes: calculating n average voltages, where the average voltage is the average of the first voltage and the second voltage corresponding to the preset pressure; substituting the n preset pressures and the n average voltages into a first formula to perform polynomial curve fitting to obtain k candidate formulas, where the candidate formulas are m-th degree polynomials and m is a positive integer; and determining the target mapping relationship from the k candidate formulas based on the preset pressure accuracy.

[0075] The first formula is:

[0076] Among them, the The average voltage, the For the preset pressure, the These are the polynomial coefficients.

[0077] The first and second voltages corresponding to the same preset pressure may be different. For example, as Figure 6 As shown, the curve fitted between the preset pressure and the first voltage during the pressurization process is steeper than the curve fitted between the preset pressure and the second voltage during the depressurization process. During the operation of the infusion device 10, there are often operations involving increases and decreases in the pressure within the infusion tube 400. Therefore, to make the mapping relationship between the pressure within the infusion tube 400 and the pressure sensor 130 more consistent with actual needs, the control circuit can calculate the average voltage of the first voltage and the second voltage corresponding to each preset pressure. Then, each group ( , Substituting the value into the first formula, we obtain the mapping relationship between the pressure inside the infusion tube 400 and the output voltage value of the pressure sensor. This is the pressure value measured by the pressure testing instrument. To detect the first output voltage during the pressurization process, pressure sensor 130 The pressure sensor 130 detects the second voltage output during the pressure reduction process.

[0078] The first formula above can be written as AW=B, calculated based on the preset pressure, the first voltage, and the second voltage respectively. j=0,1,2,…,2m; and calculate respectively j=0,1,2,…,2m; and substitute them into matrices A and B constructed in the first formula respectively, and calculate the coefficients of the polynomial by solving the system of linear equations. .

[0079] After calculating the polynomial coefficients Afterwards, multiple different polynomial fitting curves can be obtained, such as cubic, quartic, and quintic polynomial fitting curves, i.e., polynomial fitting curves corresponding to different values ​​of m. Then, based on the pressure accuracy required by the current infusion device 10, the formula that satisfies the preset pressure accuracy can be selected from these multiple fitted candidate formulas, i.e., a suitable value of m can be selected. For example, as... Figure 6 In the figure, 16 sets of pressure and voltage values ​​were fitted to obtain the final fourth-order polynomial curve. The horizontal axis represents the voltage value in mV, and the vertical axis represents the pressure value in mmHg. The final fourth-order polynomial curve between the pressure within the 400mm infusion tube and the output voltage of the pressure sensor 130 is determined to be: y = -0.00000000049x 4 +0.0000025x 3 -0.0044x 2 +4.76x-1574.45.

[0080] This application uses a first formula to perform polynomial fitting on the preset pressure and average voltage. This not only meets the needs of the infusion device in different application scenarios, but also satisfies the nonlinear fitting requirement between the pressure within the infusion tube 400 and the output voltage of the pressure sensor 130. Furthermore, it improves upon the deficiency in the linear fitting of the pressure-voltage relationship in the infusion device 10, where the pressure accuracy cannot meet the requirements for the entire measurement range. Polynomial curve fitting can cover linear fitting, improving pressure detection accuracy and expanding the coverage range.

[0081] S530. When the pump assembly is working, acquire the target voltage of the fluid in the infusion tube detected by the pressure sensor.

[0082] When the ventricular assist system is used by a patient, to save costs and facilitate patient movement, a pressure detector will no longer be used to monitor the pressure inside the infusion tubing 400. During operation of the ventricular assist system, the pressure sensor 130 in the infusion device 10 monitors the pressure in the infusion tubing 400 in real time and transmits the output voltage to the control circuit for processing and storage.

[0083] S540. Determine the target pressure corresponding to the target voltage according to the target mapping relationship.

[0084] According to the determined target mapping relationship, the control circuit maps the voltage value fed back by the pressure sensor 130 in real time into a pressure value, and transmits the pressure value to the control device 20 for display on the display screen of the control device 20, so that medical staff can understand the operation of the infusion device 10 based on the displayed pressure.

[0085] S550. Adjust the rotational speed of the pump assembly according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range.

[0086] In this application, to maintain the voltage barrier between the blood and the motor, the pressure within the infusion tubing 400 should be stabilized within a preset pressure range. When the current pressure is detected to be outside the preset pressure range, the control circuit can control the rotational speed of the pump assembly to decrease or increase the fluid flow rate within the infusion tubing 400, thereby increasing or decreasing the pressure within the infusion tubing 400.

[0087] Specifically, when the target pressure is lower than the preset pressure range, the control circuit increases the speed of the pump assembly to increase the fluid flow rate in the infusion tube 400 until the target pressure is within the preset pressure range. When the target pressure is higher than the preset pressure range, the control circuit decreases the speed of the pump assembly to decrease the fluid flow rate in the infusion tube 400 until the target pressure is within the preset pressure range.

[0088] For example, the method further includes: obtaining a target rotational speed of the ventricular assist device; determining a preset pressure range based on the target rotational speed, wherein the value of the preset pressure range is proportional to the target rotational speed.

[0089] Furthermore, the preset pressure range is the operating pressure range of the infusion tubing 400 when the ventricular assist device operates at a preset speed. When the speed of the ventricular assist device changes, for example, when the flow rate pumped by the ventricular assist device increases, causing an increase in the pressure driving blood into the motor, the pressure within the infusion tubing 400 also increases with the increase in the speed of the ventricular assist device to maintain the voltage barrier between the blood and the motor. Therefore, the preset pressure range of the infusion tubing 400 can be determined by the speed of the ventricular assist device. The higher the speed of the ventricular assist device, the higher the pressure value within this preset pressure range, but the maximum value within the preset pressure range is less than the preset alarm pressure.

[0090] As can be seen, this application proposes a pressure control method based on an infusion device. It acquires n first voltages and n second voltages corresponding to n preset pressures in the infusion tube, with these n preset pressures arranged in ascending order. A target mapping relationship between voltage and pressure is determined based on the n preset pressures, n first voltages, and n second voltages. When the pump assembly is working, the target voltage of the fluid inside the infusion tube detected by the pressure sensor is acquired. The target pressure corresponding to the target voltage is determined based on the target mapping relationship. The pump assembly speed is adjusted according to the target pressure to stabilize the pressure inside the infusion tube within the preset pressure range. This application measures the first and second voltages corresponding to the preset pressures during the increase and decrease of pressure in the infusion tube. By fitting the mapping relationship between pressure and voltage inside the infusion tube using the first and second voltages, the mapping relationship better reflects the dynamic changes of the infusion tube during actual operation, reducing the mapping error between voltage and pressure, improving the accuracy of pressure detection, and thus improving the reliability of pressure control.

[0091] The above primarily describes the solutions of the embodiments of this application from the perspective of the method execution process. It is understood that, in order to achieve the above functions, the network device includes corresponding hardware structures and / or software modules for executing each function. Those skilled in the art should readily recognize that, in conjunction with the units and algorithm steps of the various examples described in the embodiments provided herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0092] For example, this application also provides an infusion device 10, which includes an infusion tube 400 for delivering fluid, a pressure sensor 130 disposed on the outer surface of the infusion tube 400, a pump assembly for driving fluid flow, and a control circuit electrically connected to the pump assembly.

[0093] The control circuit is used to: acquire n first voltages and n second voltages corresponding to n preset pressures of the infusion tube, wherein the n preset pressures are arranged in ascending order, the first voltage is the voltage detected by the pressure sensor during the pressure increase process in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the pressure decrease process in the infusion tube, wherein n is an integer greater than 1; determine a target mapping relationship between voltage and pressure based on the n preset pressures, the n first voltages, and the n second voltages; acquire the target voltage of the fluid in the infusion tube detected by the pressure sensor when the pump assembly is working; determine the target pressure corresponding to the target voltage based on the target mapping relationship; and adjust the rotational speed of the pump assembly according to the target pressure to stabilize the pressure in the infusion tube within the preset pressure range.

[0094] For example, this application also provides a ventricular assist system, which includes:

[0095] Ventricular assist device 30;

[0096] The infusion device 10 is mechanically connected to the ventricular assist device 30. The infusion device 10 includes an infusion tube 400 for delivering fluid, a pressure sensor 130 disposed on the outer surface of the infusion tube 400, and a pump assembly for driving the fluid flow.

[0097] and a control device 20 communicatively connected to the ventricular assist device 30 and the infusion device 10, the control device 20 being used for:

[0098] Obtain n first voltages and n second voltages corresponding to n preset pressures of the infusion tube. The n preset pressures are arranged in ascending order. The first voltage is the voltage detected by the pressure sensor during the process of pressure increase in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the process of pressure decrease in the infusion tube. The n is an integer greater than 1.

[0099] The target mapping relationship between voltage and pressure is determined based on the n preset pressures, the n first voltages, and the n second voltages;

[0100] When the pump assembly is operating, the target voltage of the fluid in the infusion tube detected by the pressure sensor is acquired;

[0101] The target voltage is determined based on the target mapping relationship;

[0102] The pump assembly speed is adjusted according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range.

[0103] For example, the ventricular assist device in this application may be a mechanical circulatory support device such as a left ventricular blood pump, a right ventricular blood pump, a kidney pump, a lung pump, a dual-heart pump, or a cardiopulmonary pump, and this application does not limit it to this.

[0104] For example, this application also provides a medical device that includes the infusion device 10 or ventricular assist system described above.

[0105] The control circuits of the above-mentioned schemes have the function of implementing the corresponding steps performed by the medical device in the above-mentioned methods; the function can be implemented by hardware or by hardware executing corresponding software.

[0106] In embodiments of this application, the control circuit may also be a chip or a chip system, such as a system on chip (SoC).

[0107] Please see Figure 7 , Figure 7 This is a schematic diagram of the structure of a medical device provided in an embodiment of this application. 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 memories and configured to be executed by the one or more processors.

[0108] The above procedure includes instructions for performing the following steps: acquiring n first voltages and n second voltages corresponding to n preset pressures of the infusion tubing, wherein the n preset pressures are arranged in ascending order, the first voltages are the voltages detected by the pressure sensor during the pressure increase process in the infusion tubing, and the second voltages are the voltages detected by the pressure sensor during the pressure decrease process in the infusion tubing, wherein n is an integer greater than 1; determining a target mapping relationship between voltage and pressure based on the n preset pressures, the n first voltages, and the n second voltages; acquiring the target voltage of the fluid in the infusion tubing detected by the pressure sensor when the pump assembly is working; determining the target pressure corresponding to the target voltage based on the target mapping relationship; and adjusting the rotational speed of the pump assembly based on the target pressure to stabilize the pressure in the infusion tubing within a preset pressure range.

[0109] All relevant content in each scenario involved in the above method embodiments can be referenced from the functional description of the corresponding functional module, and will not be repeated here.

[0110] It should be understood that the aforementioned memory may include read-only memory and random access memory, and provides 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 about the device type.

[0111] In the embodiments of this application, the processor of the above-described device may be a central processing unit (CPU), or it may 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. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0112] It should be understood that "at least one" in the embodiments of this application refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0113] In implementation, each step of the above method can be completed by integrated logic circuits in the processor's hardware or by instructions in software. The steps of the method disclosed in the embodiments of this application can be directly manifested as execution by a hardware processor, or as a combination of hardware and software units within the processor. The software units can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory, and the processor executes the instructions in the memory, combining them with its hardware to complete the steps of the above method. To avoid repetition, detailed descriptions are omitted here.

[0114] This application also provides a computer storage medium storing a computer program for electronic data interchange, which causes a computer to perform some or all of the steps of any of the methods described in the above method embodiments.

[0115] This application also provides a computer program product, which includes 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 of the methods described in the above method embodiments. This computer program product can be a software installation package.

[0116] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0117] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0118] In the several embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical or other forms.

[0119] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the embodiments of this application, depending on actual needs.

[0120] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0121] If the aforementioned integrated units are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or TRP, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0122] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage device, which may include a flash drive, ROM, RAM, disk, or optical disk, etc.

[0123] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A pressure control method based on an infusion device, characterized in that, The infusion device includes an infusion tube for conveying fluid, a pressure sensor disposed on the outer surface of the infusion tube, and a pump assembly for driving fluid flow; the method includes: Obtain n first voltages and n second voltages corresponding to n preset pressures of the infusion tube. The n preset pressures are arranged in ascending order. The first voltage is the voltage detected by the pressure sensor during the process of pressure increase in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the process of pressure decrease in the infusion tube. The n is an integer greater than 1. The target mapping relationship between voltage and pressure is determined based on the n preset pressures, the n first voltages, and the n second voltages; When the pump assembly is operating, the target voltage of the fluid in the infusion tube detected by the pressure sensor is acquired; The target voltage is determined based on the target mapping relationship; The pump assembly speed is adjusted according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range. The determination of the target mapping relationship between voltage and pressure based on the n preset pressures, the n first voltages, and the n second voltages includes: The least squares method is used to perform multiple polynomial curve fittings on the n preset pressures, the n first voltages, and the n second voltages to obtain multiple mapping relationships between the pressure in the infusion tube and the output voltage value of the pressure sensor, and the target mapping relationship is determined from the multiple mapping relationships.

2. The method according to claim 1, characterized in that, The step of obtaining n first voltages and n second voltages corresponding to n preset pressures of the infusion tube includes: The pressure inside the infusion tube is sequentially increased to the n preset pressures until the preset alarm pressure is reached. Record the first voltage measured by the pressure sensor after the first time when the pressure in the infusion tube reaches the preset pressure. The pressure inside the infusion tube is sequentially reduced from the preset alarm pressure to the n preset pressure points, and the second voltage measured by the pressure sensor is recorded after the pressure inside the infusion tube reaches the preset pressure at the first time.

3. The method according to claim 1, characterized in that, The process involves using the least squares method to perform multiple polynomial curve fittings on the n preset pressures, the n first voltages, and the n second voltages to obtain multiple mapping relationships between the pressure inside the infusion tube and the output voltage value of the pressure sensor. The target mapping relationship is then determined from these multiple mapping relationships, including: Calculate n average voltages, where the average voltage is the average of the first voltage and the second voltage corresponding to a preset pressure; Substituting the n preset pressures and the n average voltages into the first formula, polynomial curve fitting is performed to obtain k candidate formulas, where each candidate formula is an m-th degree polynomial and m is a positive integer. The target mapping relationship is determined from the k candidate formulas based on a preset pressure accuracy; The first formula is: ; Among them, the The average voltage, the For the preset pressure, the These are the polynomial coefficients.

4. The method according to claim 1, characterized in that, The step of adjusting the rotational speed of the pump assembly according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range includes: When the target pressure is lower than the preset pressure range, the rotation speed of the pump assembly is increased to increase the fluid flow rate in the infusion tube until the target pressure is within the preset pressure range. When the target pressure is higher than the preset pressure range, the speed of the pump assembly is reduced to decrease the fluid flow rate in the infusion tube until the target pressure is within the preset pressure range.

5. The method according to claim 1, characterized in that, The method further includes: Obtain the operating pressure range of the infusion device; The sampling range of the preset pressure is determined based on the working pressure range; The interval between the preset pressures is determined based on the preset pressure accuracy.

6. The method according to claim 1, characterized in that, The infusion tubing is connected to the motor of the ventricular assist device; the method further includes: Obtain the target rotational speed of the ventricular assist device; The preset pressure range is determined based on the target rotational speed, and the value of the preset pressure range is proportional to the target rotational speed.

7. An infusion device, characterized in that, The infusion device includes an infusion tube for delivering fluid, a pressure sensor disposed on the outer surface of the infusion tube, a pump assembly for driving fluid flow, and a control circuit electrically connected to the pump assembly; the control circuit is used for: Obtain n first voltages and n second voltages corresponding to n preset pressures of the infusion tube. The n preset pressures are arranged in ascending order. The first voltage is the voltage detected by the pressure sensor during the process of pressure increase in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the process of pressure decrease in the infusion tube. The n is an integer greater than 1. The target mapping relationship between voltage and pressure is determined based on the n preset pressures, the n first voltages, and the n second voltages; When the pump assembly is operating, the target voltage of the fluid in the infusion tube detected by the pressure sensor is acquired; The target voltage is determined based on the target mapping relationship; The pump assembly speed is adjusted according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range. Specifically, in determining the target mapping relationship between voltage and pressure based on the n preset pressures, the n first voltages, and the n second voltages, the control circuit is used for: The least squares method is used to perform multiple polynomial curve fittings on the n preset pressures, the n first voltages, and the n second voltages to obtain multiple mapping relationships between the pressure in the infusion tube and the output voltage value of the pressure sensor, and the target mapping relationship is determined from the multiple mapping relationships.

8. A ventricular assist system, characterized in that, The ventricular assist system includes: Ventricular assist device; An infusion device mechanically connected to the ventricular assist device, the infusion device comprising an infusion tubing for delivering fluid, a pressure sensor disposed on the outer surface of the infusion tubing, and a pump assembly for driving fluid flow; And a control device communicatively connected to the ventricular assist device and the infusion device, the control device being used for: Obtain n first voltages and n second voltages corresponding to n preset pressures of the infusion tube. The n preset pressures are arranged in ascending order. The first voltage is the voltage detected by the pressure sensor during the process of pressure increase in the infusion tube, and the second voltage is the voltage detected by the pressure sensor during the process of pressure decrease in the infusion tube. The n is an integer greater than 1. The target mapping relationship between voltage and pressure is determined based on the n preset pressures, the n first voltages, and the n second voltages; When the pump assembly is operating, the target voltage of the fluid in the infusion tube detected by the pressure sensor is acquired; The target voltage is determined based on the target mapping relationship; The pump assembly speed is adjusted according to the target pressure to stabilize the pressure in the infusion tube within a preset pressure range. Specifically, in determining the target mapping relationship between voltage and pressure based on the n preset pressures, the n first voltages, and the n second voltages, the control device is used for: The least squares method is used to perform multiple polynomial curve fittings on the n preset pressures, the n first voltages, and the n second voltages to obtain multiple mapping relationships between the pressure in the infusion tube and the output voltage value of the pressure sensor, and the target mapping relationship is determined from the multiple mapping relationships.

9. A medical device, characterized in that, The method includes a processor, a memory, and a communication interface, wherein the memory stores one or more programs, and the one or more programs are executed by the processor, the one or more programs including instructions for performing the steps of the method as described in any one of claims 1-6.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program for electronic data interchange, wherein the computer program causes a computer to perform the steps of the method as described in any one of claims 1-6.

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