Blood purification apparatus and storage medium

Abstract

This application discloses a blood purification device and storage medium. The blood purification device includes a memory and a processor. When the processor executes a computer program, it performs the following: In the pre-charge test phase, it controls a heating plate to heat the replacement fluid in the fluid replenishment branch. When the detected first temperature of the replacement fluid is within a preset safe temperature range, it switches to the blood treatment phase. Then, it controls the heating plate to start heating at the initial heating temperature, receives the user-set heating target temperature, and obtains the first flow rate of the fluid replenishment branch based on the detected rotation speed of the first peristaltic pump. It determines a temperature lookup table based on the first flow rate, finds the corresponding first heating temperature of the heating plate in the temperature lookup table based on the heating target temperature, and adjusts the heating power of the heating plate using PI control feedback based on the detected actual heating temperature and the first heating temperature. In this way, this application can improve the stability and accuracy of intelligent control of the temperature of the replacement fluid in the fluid replenishment branch.

Description

Technical Field

[0001] This application relates to the field of blood purification technology, and more particularly to a blood purification device and storage medium. Background Technology

[0002] During the operation of blood purification equipment, a fluid replenishment step is required, and the replenished fluid needs to be heated. Related technologies have begun to research intelligent control functions for heating during blood purification treatment; however, these technologies face at least the following technical problems when intelligently controlling the temperature during blood purification treatment: it is difficult to adjust the temperature to the user's desired stable state during intelligent temperature control; the intelligently adjusted fluid temperature has a relatively large error; and the intelligent temperature control process is very complex, which greatly reduces the applicability of intelligent temperature control. Summary of the Invention

[0003] Based on this, embodiments of this application provide a blood purification device and storage medium that can improve the intelligent control stability and control accuracy of the replacement fluid temperature in the fluid replacement branch, improve the anti-interference performance of temperature control, and have a wider range of applications and compatibility.

[0004] In a first aspect, this application provides a blood purification device, comprising: a first temperature sensor, a second temperature sensor, a first peristaltic pump, a heating plate, a blood circuit, a fluid replacement branch, and a fluid replacement bag; the blood circuit is connected between the patient's artery and vein, a first end of the fluid replacement branch is connected to the fluid replacement bag, a second end of the fluid replacement branch is connected to the blood circuit, a heating plate is disposed on the fluid replacement branch, the first peristaltic pump is disposed on the fluid replacement branch, the first temperature sensor is disposed at the inlet of the heating plate, the second temperature sensor is disposed at the outlet of the heating plate, the fluid replacement bag is used to store replacement fluid, and the first peristaltic pump is used to control the fluid replacement branch to output replacement fluid to the blood circuit; the blood purification device further comprises: a memory and a processor, the memory being used to store a computer program, and the processor being used to execute the computer program and, when executing the computer program, to implement the following control method for the blood purification device:

[0005] When the blood purification device is in the pre-flushing test stage, the heating plate is controlled to heat the replacement fluid in the fluid infusion branch. The second temperature sensor is used to detect the temperature of the replacement fluid in the fluid infusion branch to obtain the first detection temperature. When the first detection temperature is within the preset safe temperature range, the blood purification device is controlled to switch to the blood treatment stage.

[0006] When the blood purification device switches to the blood treatment stage, it controls the heating plate to start heating the replacement fluid in the fluid infusion branch according to the preset initial heating temperature, receives the heating target temperature set by the user, detects the rotation speed of the first peristaltic pump, and obtains the first flow rate of the fluid infusion branch based on the rotation speed of the first peristaltic pump.

[0007] A temperature lookup table is determined based on the first flow rate, wherein the temperature lookup table includes the correspondence between the temperature of the displacement fluid and the heating temperature of the heating plate;

[0008] The heating temperature of the heating plate is found in the temperature lookup table according to the target heating temperature, and is used as the first heating temperature of the heating plate.

[0009] The actual heating temperature of the heating plate is detected, and the heating power of the heating plate is adjusted by PID feedback based on the actual heating temperature and the first heating temperature.

[0010] Secondly, this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, causes the processor to implement the control method for the blood purification device as described above.

[0011] This application provides a blood purification device and storage medium. During the pre-filling test phase, the replacement fluid in the infusion branch is directly heated to a preset safe temperature range. When switching to the blood therapy phase, a seamless transition to the safe infusion procedure of the infusion branch is achieved. In the blood therapy phase, the device locates the corresponding heating plate temperature based on the user-set target heating temperature. Then, based on the located heating plate temperature and the actual heating plate temperature, the heating power of the heating plate is adjusted using PID feedback. This ensures that the temperature of the replacement fluid in the infusion branch is stably maintained after heating. By setting the target heating temperature as desired by the user, the stability and accuracy of intelligent control of the replacement fluid temperature within the rehydration branch are improved. The heated replacement fluid can be continuously output to the blood circuit through the rehydration branch. Furthermore, in this embodiment, the heating temperature of the heating plate is directly determined based on the user-set target heating temperature. This avoids interference caused by factors such as the heating efficiency of the heating plate and the flow rate of the rehydration branch on the feedback adjustment process of the replacement fluid temperature. This greatly improves the anti-interference performance of the rehydration control method in this embodiment, which has a wider range of applicability and compatibility. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the blood purification device of this application;

[0013] Figure 2 This is a detailed working principle diagram of an embodiment of the blood purification device of this application;

[0014] Figure 3 This is a schematic flowchart of an embodiment of the control method for the blood purification device of this application;

[0015] Figure 4 This is a schematic diagram showing the relationship between the rotational speed of the first peristaltic pump and the flow rate of the replacement fluid in the fluid replenishment branch in one embodiment of the blood purification device of this application;

[0016] Figure 5 This is a schematic diagram of the heating area of ​​the hot plate in one embodiment of the blood purification device of this application;

[0017] Figure 6 This is a schematic diagram of a PID feedback control model in one embodiment of the blood purification device of this application;

[0018] Figure 7 This is a flowchart illustrating the control logic of PID feedback regulation in one embodiment of the blood purification device of this application;

[0019] Figure 8 This is a schematic diagram of the response curve of the heating power of the heating plate being adjusted by PID feedback in one embodiment of the blood purification device of this application;

[0020] Figure 9 This is a schematic diagram showing the change curve of the rotational speed of the second peristaltic pump and the fourth detection temperature in one embodiment of the blood purification device of this application. Detailed Implementation

[0021] The technical solutions of 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 embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0022] The flowchart shown in the attached diagram is for illustrative purposes only and does not necessarily include all content and operations / steps, nor does it necessarily have to be performed in the order described. For example, some operations / steps can be broken down, combined, or partially merged, so the actual execution order may change depending on the actual situation.

[0023] Blood purification equipment is a type of medical device that enables continuous renal replacement therapy. When performing blood purification treatment using this equipment, it is necessary to integrate and safely control all its systems (such as fluid replacement, heating, temperature control, fluid balance, and pump speed regulation) to ensure that the patient's blood is properly purified.

[0024] To improve the safety and accuracy of blood purification treatment for patients, relevant technicians have been researching and applying intelligent control of various systems in blood purification equipment. Taking the fluid replacement system of blood purification equipment as an example, during operation, the equipment needs to perform fluid replacement, and the replenished fluid needs to be heated. Research has begun on intelligent control functions for heating during blood purification treatment. However, when intelligently controlling the temperature during blood purification treatment, the technology faces at least the following technical problems: it is difficult to adjust the temperature to the user's desired stable state; the intelligently adjusted fluid temperature has a relatively large error; the intelligent temperature control process is affected by factors such as the heating plate structure and blood flow rate in the tubing, making the process very complex; all of these significantly reduce the applicability of intelligent temperature control.

[0025] In this embodiment, the replacement fluid in the rehydration branch is directly heated to a preset safe temperature range during the pre-fluidation test phase. When switching to the blood treatment phase, a seamless transition to the safe rehydration step in the rehydration branch is achieved instantly. When the blood purification device is in the blood treatment phase, the heating temperature of the corresponding heating plate is determined based on the user-set heating target temperature. Then, the heating power of the heating plate is adjusted using PID feedback based on the found heating plate temperature and the actual heating temperature of the heating plate. This ensures that the temperature of the replacement fluid in the rehydration branch is stably maintained at the user-expected heating target temperature, thus improving the intelligent control stability and accuracy of the replacement fluid temperature in the rehydration branch. The heated replacement fluid is continuously output to the blood circuit through the rehydration branch. Furthermore, this embodiment directly determines the heating temperature of the heating plate based on the user-set heating target temperature, thus avoiding interference from factors such as the heating efficiency of the heating plate and the flow rate of the rehydration branch on the feedback adjustment process of the replacement fluid temperature. This greatly improves the anti-interference performance of the rehydration control method in this embodiment, which has a wider range of applicability and compatibility.

[0026] This application discloses a control method for a blood purification device. To better illustrate the specific implementation of the control method for the blood purification device in this application, further details are provided. Figure 1The diagram shows the overall structure of the blood purification equipment. Figure 2 This demonstrates the specific working principle of the blood purification equipment; combined with Figure 1 and Figure 2 The blood purification device includes: a first temperature sensor, a second temperature sensor, a first peristaltic pump, a heating plate, a blood circuit, a fluid replenishment branch, and a fluid replenishment bag; the blood circuit is connected between the patient's artery and vein, and is used to transfer the patient's blood; wherein the blood circuit includes: a blood purifier, an arterial line, a venous line, and a venous reservoir, etc., the first end of the arterial line is connected to the patient's artery, the second end of the arterial line is connected to the blood input end of the blood purifier, the first end of the venous line is connected to the blood output end of the blood purifier, the second end of the venous line is connected to the patient's vein, and the venous reservoir is connected in series in the venous line. The arterial line outputs the patient's blood to the blood purifier, and after the blood purifier purifies the patient's blood, the venous line returns the purified blood to the patient's body, wherein the venous reservoir is set in the venous line, and the venous reservoir can play a technical role in replenishing fluids and removing air bubbles in the blood.

[0027] The first end of the fluid replacement branch is connected to the fluid replacement bag, and the second end of the fluid replacement branch is connected to the blood circuit. The heating plate is disposed on the fluid replacement branch, the first peristaltic pump is disposed on the fluid replacement branch, the first temperature sensor is disposed at the inlet of the heating plate, the second temperature sensor is disposed at the outlet of the heating plate, the fluid replacement bag is used to store replacement fluid, and the first peristaltic pump is used to control the fluid replacement branch to output replacement fluid to the blood circuit.

[0028] Specifically, when there is flowing blood in the blood circuit, the first peristaltic pump operates to provide driving force for the fluid resuscitation branch. The fluid resuscitation branch outputs replacement fluid to the blood circuit, and the blood circuit returns the replacement fluid and purified blood together to the patient's vein. The rotation of the first peristaltic pump can control the output rate of the replacement fluid in the fluid resuscitation branch. In some embodiments, the replacement fluid may contain: nutrients required by the patient or substances that have a therapeutic effect on the patient's disease; the step of outputting replacement fluid to the blood circuit through the fluid resuscitation branch is the fluid resuscitation step in the blood purification treatment process. The fluid resuscitation step can improve the effect of the patient's blood purification treatment and is also an essential step in the patient's blood purification treatment process.

[0029] During the fluid resuscitation process, the replacement fluid in the resuscitation circuit needs to be heated using a heating plate. Since the replacement fluid is an external fluid, the temperature of the purified blood needs to reach the body's safe physiological temperature, such as 35.6℃-36.8℃. The replacement fluid is stored in resuscitation bags, and in clinical practice, to maintain the physiological activity of the fluid within these bags, they need to be stored at low temperatures, typically below 10℃. During blood therapy, the replacement fluid in the resuscitation bags needs to be heated to the body's safe physiological temperature before being output to the blood circuit via the resuscitation circuit. The heated replacement fluid is then reinfused into the patient along with the blood. Without the heating plate, the resuscitation circuit would directly output unheated replacement fluid to the blood circuit, causing a rapid drop in blood temperature. If this blood, not reaching the body's safe physiological temperature, is reinfused into the patient, it can cause discomfort and, in severe cases, even endanger the patient's life. Therefore, heating the replacement fluid in the infusion line using a heating plate is an essential step in the patient's blood purification treatment.

[0030] It should be noted that the first peristaltic pump is an existing electronic device in this technical field, and its specific structure and working principle will not be discussed in detail here.

[0031] The blood purification device further includes a memory and a processor; the memory is used to store a computer program, and the processor is used to execute the computer program and, when executing the computer program, implement the control method of the blood purification device as described below.

[0032] See Figure 3 The control method of the blood purification device according to the embodiments of this application includes the following steps:

[0033] Step S101: When the blood purification device is in the pre-flushing test stage, the heating plate is controlled to heat the replacement fluid in the fluid replenishment branch. The second temperature sensor is used to detect the temperature of the replacement fluid in the fluid replenishment branch to obtain a first detection temperature. When the first detection temperature is within the preset safe temperature range, the blood purification device is controlled to switch to the blood treatment stage.

[0034] Specifically, the working process of a blood purification device can be divided into the following stages: tube installation, pre-flushing test, blood treatment, and blood return. In the tube installation stage, components of the blood purification device need to be installed according to the selected blood purification treatment mode, such as the blood circuit, fluid supply line, and fluid bag. In the pre-flushing test stage, the blood circuit, fluid supply line, and other components need to be flushed with pre-flushing fluid to remove impurities and air. In the blood treatment stage, blood is connected to the blood circuit for blood purification treatment, and the fluid supply line outputs heated replacement fluid to the blood circuit. In the blood return stage, the patient's blood purification treatment process needs to be completed, and all remaining blood in the blood circuit needs to be returned to the patient's body.

[0035] When the blood purification equipment is in the pre-flushing test stage, the first peristaltic pump is controlled to operate, so that the replacement fluid is connected to the replenishment branch. The heating plate heats the replacement fluid in the replenishment branch. The heated replacement fluid is in the preheating step and is used for standby. When switching to the blood treatment stage, the preheated replacement fluid can be directly output to the blood circuit, avoiding the temperature error of the replacement fluid caused by the switching between the blood purification equipment in the pre-flushing test stage and the blood treatment stage.

[0036] The preset safe temperature range is used to evaluate whether the replacement fluid in the rehydration circuit, after being heated, has reached the safe blood temperature standard for the human body. The preset safe temperature range is a value set by the user in advance, such as 35℃-37℃. When the replacement fluid in the rehydration circuit is heated by the heating plate, the heated replacement fluid will be safely output to the blood circuit only when its temperature is within the preset safe temperature range. This ensures the safety of the heated replacement fluid output to the blood circuit and allows for a smooth switch between the pre-flush test stage and the blood treatment stage.

[0037] During the pre-charge test, if the first temperature detected by the second temperature sensor is not within the preset safe temperature range, the blood purification equipment cannot switch to the blood treatment stage. This indicates that the heating process of the replacement fluid in the fluid replacement branch by the heating plate is not qualified, and the temperature of the heated replacement fluid is too high or too low. At this time, the heating process of the heating plate needs to be readjusted until the temperature of the heated replacement fluid is within the preset safe temperature range.

[0038] Step S102: When the blood purification device switches to the blood treatment stage, the heating plate is controlled to start heating the replacement fluid in the fluid replenishment branch according to the preset initial heating temperature, the user-set heating target temperature is received, the rotation speed of the first peristaltic pump is detected, and the first flow rate of the fluid replenishment branch is obtained according to the rotation speed of the first peristaltic pump.

[0039] Specifically, when the blood purification equipment switches to the blood therapy stage, the blood pump installed in the blood circuit starts to rotate, providing driving force to the blood circuit, which then transports blood. The blood flow rate within the blood circuit changes according to the user's instructions. Blood purification treatment can be performed on the patient's blood through the blood circuit. The heating plate is controlled to heat the replacement fluid in the rehydration branch at a preset initial heating temperature, thus initiating the heating step of the rehydration branch. It should be noted that the initial heating temperature refers only to the temperature of the heating plate at the moment heating begins; the actual heating temperature will change during the heating process. The target heating temperature is the user's desired temperature for the replacement fluid, for example, 36.5℃, which is a standard value set by the user based on clinical experience.

[0040] The rotational speed of the first peristaltic pump can be detected using a Hall sensor, which is an electronic component in related technologies. The specific steps of "detecting the rotational speed of the first peristaltic pump using a Hall sensor" are equivalent to the specific steps of "detecting the rotational speed of the motor using a Hall sensor." The specific principle of "detecting the rotational speed of the first peristaltic pump using a Hall sensor" will not be explained in detail here.

[0041] When the first peristaltic pump rotates, it provides driving force to the replenishment branch, causing the replacement fluid within the branch to flow at a specific flow rate. There is a direct correlation between the rotational speed of the first peristaltic pump and the flow rate of the replacement fluid in the replenishment branch; this correlation is analogous to the correlation between the rotational speed of the motor and the flow rate of the replacement fluid in the replenishment branch. Therefore, once the rotational speed of the first peristaltic pump is detected, the flow rate of the replacement fluid in the replenishment branch (i.e., the first flow rate) can be obtained. Specifically, the method for obtaining the first flow rate of the replenishment branch based on the rotational speed of the first peristaltic pump can be as follows: Technicians can obtain the flow rate of the replacement fluid in the replenishment branch by conducting multiple clinical trials on the rotational speed of the first peristaltic pump. Through these multiple clinical trials, a curve showing the relationship between the rotational speed of the first peristaltic pump and the flow rate of the replacement fluid in the replenishment branch can be obtained, such as... Figure 4 As shown. Therefore, once the rotational speed of the first peristaltic pump is detected, according to Figure 4 The corresponding first flow rate (i.e., the flow rate of the displacement fluid in the replenishment branch) can be found immediately from the relationship curve in the figure; therefore, this embodiment will immediately obtain the heating target temperature and the first flow rate, so as to set the parameters in advance for the subsequent PID control.

[0042] It should be noted that, Figure 4The relationship curves in the diagram are obtained by those skilled in the art after conducting multiple clinical trials. For example, during clinical trials, by adjusting the speed of the first peristaltic pump, the flow rate of the replacement fluid in the rehydration branch is measured at different pump speeds. This yields two values: "speed of the first peristaltic pump" and "flow rate of the replacement fluid in the rehydration branch" (essentially, points on a coordinate system). After multiple clinical trials, multiple points are obtained on the coordinate system. Connecting these points yields a curve similar to... Figure 4 The relationship curve in the middle.

[0043] Step S103: Determine a temperature lookup table based on the first flow rate, wherein the temperature lookup table includes the correspondence between the temperature of the displacement fluid and the heating temperature of the heating plate.

[0044] When the replacement fluid in the replenishment branch is heated by a heating plate, the heating principle is as follows: the heating plate generates heat, and when the replacement fluid in the replenishment branch flows through the heating area of ​​the heating plate, the heating plate transfers heat to the replacement fluid in the replenishment branch (for information on the heating area of ​​the heating plate, please refer to...). Figure 5 When the heating plate heats the displacement fluid in the replenishment branch, the temperature of the displacement fluid output from the heating plate outlet is affected by two factors: 1. the heating temperature of the heating plate; 2. the heating efficiency of the heating plate. The heating efficiency of the heating plate refers to the time it takes for the displacement fluid to flow through the heating area of ​​the heating plate. The longer the time, the longer the heating plate heats the displacement fluid in the replenishment branch, and the longer the displacement fluid takes to heat up in the replenishment branch. Conversely, the shorter the time, the shorter the heating plate heats the displacement fluid in the replenishment branch, and the shorter the displacement fluid takes to heat up in the replenishment branch.

[0045] The time it takes for the displacement fluid to flow through the heating zone of the heating plate is affected by the flow rate of the displacement fluid in the replenishment branch. Generally, the flow rate of the displacement fluid in the replenishment branch and the time it takes for the displacement fluid to flow through the heating zone of the heating plate are inversely proportional.

[0046] Therefore, when the initial flow rate of the replenishment branch changes, the heating efficiency of the heating plate will change, and the relationship between the temperature of the replacement fluid and the heating temperature of the heating plate will also change. It is necessary to first determine the initial flow rate of the replenishment branch, and then determine a temperature lookup table based on the initial flow rate. The temperature lookup table contains the relationship between the temperature of the replacement fluid and the heating temperature of the heating plate. Based on this relationship, a convenient conversion between the temperatures of the replacement fluid and the heating temperature of the heating plate can be achieved.

[0047] It should be noted that the temperature lookup table is determined based on the first flow rate. The specific method for setting the temperature lookup table is as follows: after determining the flow rate of the replacement fluid in the replenishment branch, the flow rate of the replacement fluid in the replenishment branch is kept constant. The heating temperature of the heating plate is continuously adjusted, and then the temperature of the replacement fluid in the replenishment branch is detected by the second temperature sensor. In this way, the corresponding values ​​of the temperature of the replacement fluid and the heating temperature of the heating plate are obtained.

[0048] For example, when the flow rate of the replacement fluid in the replenishment branch (i.e., the first flow rate) is 3 ml / min, the resulting temperature lookup table is shown in Table 1 below:

[0049] Table 1

[0050]

[0051] For example, when the flow rate of the replacement fluid in the replenishment branch (i.e., the first flow rate) is 5 ml / min, the resulting temperature lookup table is shown in Table 2 below:

[0052] Table 2

[0053]

[0054] After the initial flow rate is determined, the temperature lookup table is directly determined based on the initial flow rate. The conversion relationship between the temperature of the displacement fluid and the heating temperature of the heating plate can be directly obtained from the temperature lookup table. Based on this conversion relationship, the heating temperature of the heating plate can be obtained, and the heating state of the heating plate can be directly adjusted by feedback. This overcomes the interference caused by factors such as the structure of the heating plate and the heating time of the heating plate in the PID feedback adjustment process, and improves the accuracy of feedback adjustment of the heating state of the heating plate.

[0055] Step S104: Find the corresponding heating temperature of the heating plate in the temperature lookup table according to the target heating temperature, and use it as the first heating temperature of the heating plate.

[0056] Step S105: Detect the actual heating temperature of the heating plate, and adjust the heating power of the heating plate using PID (Proportion Integral Differential) feedback based on the actual heating temperature and the first heating temperature.

[0057] Specifically, when the user sets the target heating temperature, which refers to the user's desired replacement fluid temperature, the heating temperature of the heating plate corresponding to the target heating temperature can be found based on the temperature lookup table mentioned above. This is the first heating temperature of the heating plate.

[0058] The actual heating temperature of the heating plate is detected by a temperature sensor. The heating power of the heating plate is adjusted by PID feedback based on the difference between the actual heating temperature and the first heating temperature. After the heating power of the heating plate is dynamically adjusted, the temperature of the replacement fluid at the outlet of the heating plate can always be close to the heating target temperature. This ensures that the temperature of the heated replacement fluid is always close to the user's desired heating target temperature. The fluid replenishment branch outputs the heated replacement fluid to the blood circuit to ensure the safety of blood flow in the blood circuit.

[0059] The following is a detailed explanation of PID feedback regulation:

[0060] The overall approach to PID feedback regulation is as follows: A closed-loop design, i.e., the PID algorithm, is employed. The CPU (Central Processing Unit) independently outputs a PWM (pulse width modulation) signal corresponding to the heating enable signal of the heating plate. A high level enables heating, and a low level disables it. The heating plate is independently controlled. The software calculates a suitable heating power based on the deviation between the actual heating temperature fed back by the temperature sensor on the heating plate and the initial heating temperature. This is achieved by adjusting the duty cycle (0%-100%) of the output PWM signal to regulate the temperature rise and fall of the heating plate. At regular intervals, the deviation between the actual heating temperature and the initial heating temperature is collected again to further calculate a suitable heating power. This process is repeated until the actual heating temperature of the heating plate approaches or equals the initial heating temperature, thus achieving the heating objective.

[0061] PID feedback control model, such as Figure 6 As shown, it linearly combines the proportional, integral, and derivative of the deviation e(t) between the given value r(t) and the actual output value y(t) to form the control quantity u(t) output. In this embodiment, the heating plate is the controlled object in the PID feedback regulation.

[0062] PID feedback control uses the error signal to control the heating plate. The control model of PID feedback control is itself the sum of the proportional, integral, and derivative components. Here, the parameters in PID feedback control at time t are defined as follows:

[0063] 1. Input quantity is r(t): first heating temperature.

[0064] 2. PID calculation output u(t): heating power of the heating plate.

[0065] 3. Output of PID feedback regulation y(t): The actual heating temperature of the heating plate.

[0066] 4. Deviation e(t) of PID feedback regulation: First heating temperature - actual heating temperature of heating plate.

[0067] Continuous state formula for PID feedback control:

[0068]

[0069] Based on the continuous state formula above, it can be directly concluded that PID feedback regulation is actually a process of controlling the deviation.

[0070] The practical meanings of the parameters in PID feedback control are as follows:

[0071] 1. Proportional term K p :

[0072] When the deviation e(t) is 0, the proportional term has no effect; the proportional term only takes effect when the deviation e(t) exists.

[0073] 2. Integral Term

[0074] The integral term is mainly used to eliminate steady-state error, which is the difference between the output and the setpoint after the control model of PID feedback regulation has stabilized. The integral term is actually the process of accumulating the deviation, adding the accumulated deviation to the original system to offset the steady-state error caused by the system.

[0075] 3. Differential term

[0076] The differential term reflects the pattern or trend of the deviation. Anticipatory adjustments are made based on the trend of the deviation, thereby increasing the system's responsiveness.

[0077] The above is the continuous-state formula for PID feedback control. Next, we will discretize the continuous system of PID feedback control to facilitate CPU processing. The discretized PID formula is as follows:

[0078] u(t) = K p (e(t)+K i K p ∑e(t)+K d K p (e(t)-e(t-1)))

[0079] Among them, the three parameters Kp, Ki, and Kd need to be tuned during the PID feedback regulation process to enable the PID feedback regulation to have the best temperature feedback regulation performance.

[0080] When using PID feedback regulation to control the heating process of the heating plate, the control logic of PID feedback regulation is as follows:

[0081] Combination Figure 7 Before the heating plate is activated, its heating power is 0. The heating function is only enabled after the blood purification equipment switches to the blood treatment stage. After setting the target heating temperature on the blood purification equipment's display screen, turning on the heating button will transmit the set speed of the first peristaltic pump and the target heating temperature of the replacement fluid to the lower-level STM32 microcontroller via CAN communication. Upon receiving these parameters, the lower-level STM32 microcontroller will find the corresponding heating temperature of the heating plate in the temperature lookup table, using it as the initial heating temperature. The initial heating temperature is then compared with the actual heating temperature of the heating plate collected by the CPU using a PID controller to calculate an appropriate heating power. The heating power is recalculated every second during the heating process, and the PID controller adjusts the power based on the initial heating temperature and the actual heating temperature of the heating plate. The temperature is intelligently adjusted. The heating power of the heating plate is calculated using proportional, integral, and differential methods based on the difference between the initial heating temperature and the actual heating temperature. When the difference is positive, the heating power gradually increases until it approaches 100%. When the difference is negative, the heating power gradually decreases until it approaches 0%. When the difference is zero, the heating power gradually tends to remain constant. After approximately 30 minutes of heating, the difference between the initial heating temperature and the actual heating temperature stabilizes within ±1℃, and the fluctuation range of the heating power narrows, thus reaching and maintaining the initial heating temperature. For easier understanding... Figure 8 The diagram shows the response curve of PID feedback regulation of the heating power of the heating plate.

[0082] It needs to be emphasized again that the first heating temperature is the heating temperature of the heating plate, which is not equal to the temperature of the displacement fluid at the outlet of the heating plate. The heating plate transfers heat to the displacement fluid in the replenishment branch for heating, and there will be energy loss. When the heating plate heats the displacement fluid in the replenishment branch according to the first heating temperature, it can ensure that the temperature of the displacement fluid at the outlet of the heating plate reaches the target heating temperature set by the user.

[0083] Therefore, in this embodiment, after switching between the temperature of the replacement fluid and the heating temperature of the heating plate, the heating power of the heating plate is adjusted by PID feedback based on the difference between the actual heating temperature and the first heating temperature. This feedback adjustment method eliminates the interference caused by factors such as the heating power of the heating plate and the flow rate of the fluid replenishment branch on the PID feedback adjustment process. The heating plate has higher heating control accuracy and heating control stability for the replacement fluid in the fluid replenishment branch. The heated replacement fluid can be safely output to the blood circuit, and the patient's blood purification treatment process can always be kept in a safe state.

[0084] In some embodiments, in step S105, when the heating power of the heating plate is adjusted by PID feedback based on the actual heating temperature and the first heating temperature, the control method further includes:

[0085] Step S106: Use the first temperature sensor to detect the temperature of the replacement fluid in the replenishment branch to obtain the second detection temperature.

[0086] Step S107: Use the second temperature sensor to detect the temperature of the replacement fluid in the replenishment branch to obtain the third detection temperature.

[0087] Step S108: When the absolute value of the temperature difference between the second detection temperature and the third detection temperature is less than the preset start-up difference, a first alarm signal is issued.

[0088] Specifically, the second detection temperature represents the temperature of the replacement fluid before heating, and the third detection temperature represents the temperature of the replacement fluid after heating. The absolute value of the temperature difference between the second and third detection temperatures represents the degree of temperature change of the replacement fluid in the replenishment branch caused by the heating process of the heating plate. The larger the absolute value of the temperature difference between the second and third detection temperatures, the more obvious the heating effect of the heating plate on the replacement fluid in the replenishment branch, and the greater the temperature rise of the replacement fluid in the replenishment branch. The smaller the absolute value of the temperature difference between the second and third detection temperatures, the less obvious the heating effect of the heating plate on the replacement fluid in the replenishment branch, and the smaller the temperature rise of the replacement fluid in the replenishment branch.

[0089] The heating efficiency of the heating plate is determined based on the absolute value of the temperature difference between the second and third detection temperatures. If the absolute value of the temperature difference between the second and third detection temperatures is less than the preset start-up difference, it indicates that the heating efficiency of the heating plate is too low. The heating plate does not play a significant role in heating the replacement fluid in the replenishment branch, or the heating effect is negligible. This situation is usually caused by the temperature of the replacement fluid in the replenishment bag being already very high, close to the user-set heating target temperature. In this case, it is no longer necessary for the heating plate to heat the replacement fluid in the replenishment branch.

[0090] It should be noted that the preset start-up difference represents the minimum change amplitude. This preset start-up difference is used to determine whether the temperature change of the replacement fluid before and after heating meets the heating requirements of the heating plate. The preset start-up difference can be set based on clinical experience; for example, a preset start-up difference of 1℃. Only when the absolute value of the temperature difference between the second and third detection temperatures is greater than or equal to the preset start-up difference is the heating plate in normal operating condition, and the heating plate is performing its normal heating function. When the absolute value of the temperature difference between the second and third detection temperatures is less than the preset start-up difference, it indicates that the heating process of the heating plate has not caused a significant change in the temperature of the replacement fluid in the replenishment branch, and the heating plate is not providing significant heating effect. The heating plate is ineffective in heating the replacement fluid in the replenishment branch, and a first alarm signal (e.g., an audible and visual alarm) is issued. Upon noticing the first alarm signal, the user will immediately address the ineffective heating state of the heating plate.

[0091] Therefore, this embodiment can determine whether the heating state of the heating plate on the replacement fluid in the replenishment branch is ineffective, and when it is determined that the heating state of the heating plate is ineffective, it will immediately issue a first alarm signal to issue a prompt message; in this way, the ineffective heating state of the heating plate can be identified in time, reducing the power consumption of the heating plate.

[0092] It should be noted that the first temperature sensor detects the temperature of the replacement fluid in the replenishment branch in real time according to the first sampling period, and the second temperature sensor detects the temperature of the replacement fluid in the replenishment branch in real time according to the second sampling period. At the same time, the first temperature sensor and the second temperature sensor respectively detect the temperature of the replacement fluid in the replenishment branch. Then, by comparing the temperature sampling value of the first temperature sensor (that is, the second detection temperature) and the temperature sampling value of the second temperature sensor (that is, the third detection temperature), it is possible to determine whether the heating state of the heating plate is invalid.

[0093] In some embodiments, step S105, which involves adjusting the heating power of the heating plate according to the actual heating temperature and the first heating temperature using PID feedback, may include: setting a PID controller, tuning the parameters of the PID controller, using the first heating temperature as the input of the PID controller, using the actual heating temperature as the feedback of the PID controller, and using the heating power of the heating plate as the adjustment of the PID controller.

[0094] Specifically, the structural model of the PID controller can be found in [reference needed]. Figure 6 As shown, the structural model of the PID controller can be represented by the following mathematical formula:

[0095]

[0096] In the above formula, s is a complex variable, and K P K is the proportionality coefficient. T K is the integral coefficient. D K is the differential coefficient. P K T K D All three of these are parameters of the PID controller. Once the parameters of the PID controller are tuned, the heating process of the heating plate can be PID-controlled so that the temperature of the displacement fluid in the replenishment branch after being heated by the heating plate can quickly approach the target heating temperature and maintain the temperature of the heated displacement fluid in a stable state.

[0097] It should be noted that PID controller parameter tuning can employ methods from relevant technologies, such as the Ziegler-Nichols (ZN) tuning method. The ZN tuning method is currently the most widely used parameter tuning method for PID controllers. This method determines the critical gain and critical period of the controlled object through physical experiments to complete the parameter tuning process. Besides the ZN tuning method, genetic algorithms, backpropagation (BP) neural network technology, and other methods can also be used for PID controller parameter tuning. Since the parameter tuning methods for PID controllers are all traditional methods in this technical field, the specific working principles of these methods will not be discussed in detail here.

[0098] In some embodiments, when the blood purification device switches to the blood therapy stage, the control method may further include:

[0099] Step S109: Detect the flow time of the replacement fluid from the inlet of the heating plate to the outlet of the heating plate.

[0100] Step S110: Tune the parameters of the PID controller according to the flow time.

[0101] Specifically, during the blood therapy phase, the operation of the first peristaltic pump is controlled, and the first flow rate of the fluid replenishment branch is obtained based on the rotational speed of the first peristaltic pump. The fluid replenishment branch outputs the replacement fluid to the blood circuit according to the first flow rate. The flow time represents the time the replacement fluid stays in the heating area of ​​the heating plate. The flow time is the continuous heating time of the replacement fluid by the heating plate. Since the heating area of ​​the heating plate remains unchanged, the flow time is determined by the first flow rate of the fluid replenishment branch. When the first flow rate is larger, the flow time is smaller; when the first flow rate is smaller, the flow time is larger.

[0102] The flow time and the PID feedback regulation of the heating plate are directly related. When the replacement fluid in the replenishment branch is heated by the heating plate, the flow time and the response time of the PID controller are proportional. For example, the response time of the PID controller = preset coefficient * flow time. Therefore, when the response time of the PID controller is obtained based on the flow time, the proportional coefficient, integral coefficient, and derivative coefficient of the PID controller are configured respectively. After the configuration is completed, the parameter tuning process of the PID controller is finished. It should be noted that how to set the proportional coefficient, integral coefficient, and derivative coefficient of the PID controller based on the response time involves the specific steps in the parameter tuning method of related technologies. Therefore, the specific steps of "parameter tuning of the PID controller based on the response time of the PID controller" will not be described in detail here.

[0103] In this embodiment, the parameters of the PID controller are tuned according to the flow time of the displacement fluid, which can improve the flexibility of PID feedback adjustment for the heating process of the heating plate. The heating temperature of the heating plate after PID feedback adjustment can fully meet the heating requirements of the displacement fluid, and the temperature of the displacement fluid after heating has higher safety.

[0104] In some embodiments, the blood purification device further includes: a third temperature sensor, a fourth temperature sensor, a second peristaltic pump, a waste liquid branch, and a waste liquid bag; the first end of the waste liquid branch is connected to the blood circuit, the second end of the waste liquid branch is connected to the waste liquid bag, the second peristaltic pump is disposed on the waste liquid branch, the fourth temperature sensor is disposed on the blood circuit, the third temperature sensor is disposed on the waste liquid bag, the waste liquid bag is used to store waste liquid, and the second peristaltic pump is used to control the waste liquid branch to output the waste liquid generated by the blood circuit to the waste liquid bag.

[0105] When blood is flowing within the blood circuit, blood purification of the patient's blood removes excess water and harmful substances. These excess water and harmful substances form waste fluid, which is discharged through a waste fluid branch to a waste fluid bag for storage. During blood purification treatment, a third temperature sensor detects the temperature of the waste fluid in the waste fluid bag, representing the heat lost from the patient's blood. A fourth temperature sensor detects the temperature of the blood within the blood circuit, representing the patient's blood temperature.

[0106] At this time, the control method may further include:

[0107] Step S111: When the blood purification device switches to the blood treatment stage, the rotation speed of the second peristaltic pump is detected.

[0108] The rotational speed of the second peristaltic pump represents the driving force it provides to the waste liquid branch. Generally, the higher the rotational speed of the second peristaltic pump, the greater the driving force it provides to the waste liquid branch, and the greater the waste liquid flow rate in the waste liquid branch (and the greater the second flow rate in the waste liquid branch). When the blood purification equipment switches to the blood treatment stage, the second peristaltic pump is controlled to rotate to drive the waste liquid branch to output waste liquid to the waste liquid bag. The specific value of the rotational speed of the second peristaltic pump is affected by the blood flow rate in the blood circuit. When the blood flow rate in the blood circuit is greater, the rotational speed of the second peristaltic pump is also greater, and the driving force provided to the waste liquid branch by the rotation of the second peristaltic pump is greater, and the blood flow rate in the waste liquid branch is also greater.

[0109] After detecting the rotational speed of the second peristaltic pump, the second flow rate of the waste liquid branch can also be obtained based on the rotational speed of the second peristaltic pump. It should be noted that obtaining the second flow rate of the waste liquid branch based on the rotational speed of the second peristaltic pump can refer to the specific implementation method of "obtaining the first flow rate of the replenishment branch based on the rotational speed of the first peristaltic pump" in the above text.

[0110] Step S112: Use the third temperature sensor to detect the temperature of the waste liquid inside the waste liquid bag to obtain the fourth detection temperature.

[0111] Step S113: Use the fourth temperature sensor to detect the blood temperature in the blood circuit to obtain the fifth detection temperature.

[0112] Step S114: Use the second temperature sensor to detect the temperature of the replacement fluid in the replenishment branch to obtain the third detection temperature.

[0113] Step S115: When the difference between the fourth and third detected temperatures is greater than the product of the fifth detected temperature multiplied by a first preset percentage (e.g., 10%) (i.e., fourth detected temperature - third detected temperature > fifth detected temperature * first preset percentage), a second alarm signal is issued; when the difference between the third and fourth detected temperatures is greater than the product of the fifth detected temperature multiplied by a second preset percentage (e.g., 20%) (i.e., third detected temperature - fourth detected temperature > fifth detected temperature * second preset percentage), a third alarm signal is issued; when the difference between the fourth and fifth detected temperatures is greater than the product of the fifth detected temperature multiplied by a second preset percentage (e.g., 20%) (i.e., third detected temperature - fourth detected temperature > fifth detected temperature * second preset percentage), a third alarm signal is issued; when the difference between the fourth and fifth detected temperatures is greater than the product of the fifth detected temperature multiplied by a first preset percentage (e.g., 10%), a second alarm signal is issued; when the difference between the fourth and fifth detected temperatures is greater than the product of the fifth detected temperature multiplied by a first preset percentage (e.g., 10%), a third alarm signal is issued; when the difference between the fifth and fifth detected temperatures is greater than the product of the fifth detected temperature multiplied by a first preset percentage (e.g., 20%), a third alarm signal is issued; when the difference between the fifth ... When the difference between the fourth and third detected temperatures is less than or equal to the product of the fifth detected temperature multiplied by a first preset percentage (e.g., 10%) (i.e., fourth detected temperature - third detected temperature ≤ fifth detected temperature * first preset percentage), and the difference between the third and fourth detected temperatures is less than or equal to the product of the fifth detected temperature multiplied by a second preset percentage (e.g., 20%) (i.e., third detected temperature - fourth detected temperature ≤ fifth detected temperature * second preset percentage), the curve showing the change in the rotational speed of the second peristaltic pump versus the fourth detected temperature is plotted.

[0114] Specifically, the fourth detection temperature represents the heat lost from the patient's blood, the fifth detection temperature represents the blood temperature inside the patient's body, and the third detection temperature represents the heat added to the patient's blood. Therefore, the absolute value of the difference between the fourth and third detection temperatures represents the degree of change in blood temperature within the blood circuit caused by the fluid replenishment and waste fluid removal steps during blood purification treatment. When the fourth detection temperature is greater than the third detection temperature, it indicates that the heat lost from the blood is greater than the heat added to the blood, causing a decrease in blood temperature within the blood circuit. When the fourth detection temperature is less than the third detection temperature, it indicates that the heat lost from the blood is less than the heat added to the blood, causing an increase in blood temperature within the blood circuit. Therefore, this embodiment compares the difference between the fourth and third detection temperatures and determines whether the heat lost and the heat added during blood purification treatment are within a normal range.

[0115] Specifically, this embodiment uses the fifth detection temperature as a reference benchmark. Based on this benchmark, it is possible to quantitatively determine whether the heat within the blood circuit is fluctuating. The fifth detection temperature multiplied by the first preset percentage (e.g., 10%) represents the allowable value for a decrease in blood temperature within the blood circuit. The fifth detection temperature multiplied by the second preset percentage (e.g., 20%) represents the allowable value for an increase in blood temperature within the blood circuit. When the fourth detection temperature minus the third detection temperature exceeds the fifth detection temperature multiplied by the first preset percentage, it indicates that the heat loss from the blood in the blood circuit is too great, exceeding the safe value. In this case, the second alarm signal will be issued to alert the user to the fault. Upon noticing the second alarm signal, the user will immediately address the fault in the blood temperature within the blood circuit to ensure that the blood in the blood circuit remains in a normal flow state.

[0116] If the third detection temperature minus the fourth detection temperature exceeds the fifth detection temperature multiplied by the second preset percentage, it indicates that the heat added to the blood circuit is too high and exceeds the safe value. In this case, the third alarm signal will be issued to the user to indicate the fault. Once the user notices the third alarm signal, they will immediately address the fault in the blood temperature within the blood circuit.

[0117] The values ​​“first preset percentage (e.g., 10%)” and “second preset percentage (e.g., 20%)” are derived by those skilled in the art based on clinical experience. Therefore, the specific principles behind the determination of these two values ​​will not be described in detail here.

[0118] When the fourth detection temperature - the third detection temperature ≤ the fifth detection temperature * the first preset percentage, and the third detection temperature - the fourth detection temperature ≤ the fifth detection temperature * the second preset percentage, this indicates that the heat lost from the blood in the blood circuit and the heat replenished in the blood circuit are in equilibrium. By plotting the change curves of the second peristaltic pump speed and the fourth detection temperature, the fluctuation state between the waste liquid temperature in the waste bag and the speed of the second peristaltic pump can be obtained. Furthermore, the change curves of the second peristaltic pump speed and the fourth detection temperature are displayed on the screen of the blood purification equipment, as shown below. Figure 9 As shown, users can see the curves of these two changes on the display screen. Based on these curves, users can conduct in-depth research on whether the change in the speed of the second peristaltic pump affects the temperature of the waste liquid generated during the blood purification treatment process. Based on the curves of the change in the speed of the second peristaltic pump and the fourth detection temperature, users can monitor the patient's blood purification treatment status in real time.

[0119] In some embodiments, the control method may further include:

[0120] Step S116: Calibrate the heating target temperature according to the fifth detection temperature.

[0121] At this time, step S104, which involves finding the corresponding heating temperature of the heating plate in the temperature lookup table based on the heating target temperature, as the first heating temperature of the heating plate, may include: finding the corresponding heating temperature of the heating plate in the temperature lookup table based on the calibrated heating target temperature, as the first heating temperature of the heating plate.

[0122] Specifically, in S102, the user will set the heating target temperature according to the clinical treatment standards. The heating target temperature is a standard value. During the blood treatment stage, when the patient's blood is purified, the heating target temperature needs to be calibrated according to the fifth detection temperature. After calibration, the heating target temperature can be closer to the patient's blood temperature, which improves the heating safety of the replacement fluid in the fluid replacement step.

[0123] For example, the heating target temperature is calibrated based on the fifth detection temperature, and the specific calibration method can be expressed by the following formula:

[0124] The calibrated target heating temperature = (the target heating temperature before calibration + the fifth detection temperature) / 2;

[0125] As per the formula above, when the fifth detected temperature is greater than the target heating temperature, the target heating temperature is increased; when the fifth detected temperature is less than the target heating temperature, the target heating temperature is decreased. The corresponding heating temperature of the heating plate can be found in the temperature lookup table based on the calibrated target heating temperature. The heating process of the heating plate is then PID-regulated based on the calibrated first heating temperature. This ensures that the temperature of the replacement fluid after heating by the heating plate fully meets the safety requirements of the patient's blood purification treatment, reducing the heating error of the replacement fluid in the fluid replacement circuit.

[0126] In some embodiments, the blood purification device further includes: a second weighing sensor; the second weighing sensor is disposed at the bottom of the blood purification device, the waste liquid bag is suspended on the second weighing sensor, and the second weighing sensor is used to weigh the waste liquid bag.

[0127] At this time, the control method may further include:

[0128] Step S117: Plot the temperature change curve of the fifth detected temperature over time. The temperature change curve can also be displayed.

[0129] Step S118: Weigh the waste liquid bag using the second weighing sensor to obtain a second weight detection value.

[0130] Step S119: Detect whether the fifth detection temperature is within a preset normal temperature range, which is set according to the patient's physiological characteristic parameters.

[0131] Step S120: When the fifth detected temperature is not within the normal temperature range, a fourth alarm signal is issued.

[0132] Step S121: When the fifth detection temperature is within the normal temperature range, calculate the weight increase rate of the waste liquid bag based on the second weight detection value, calculate the ratio between the fifth detection temperature and the weight increase rate, and adjust the rotation speed of the second peristaltic pump according to the ratio.

[0133] Specifically, the patient's physiological characteristics include: the patient's gender, age, heart rate, temperature, and blood temperature. Based on these physiological characteristics, a normal temperature range can be set. Those skilled in the art can select the normal temperature range based on some technical common sense in the field, such as a normal temperature range of 35.9℃-36.8℃.

[0134] It should be noted that there is a significant difference between the normal temperature range and the preset safe temperature range. The preset safe temperature range is used to determine whether the temperature of the replacement fluid in the rehydration circuit is within the normal range; the normal temperature range is used to determine whether the blood temperature in the blood circuit is within the normal range. Therefore, the normal temperature range and the preset safe temperature range are used to determine whether the temperature of different fluids is normal.

[0135] Specifically, when the fifth detection temperature is within the normal temperature range, it indicates that the blood temperature in the blood circuit is normal; the weight increase rate of the waste bag represents the rate at which waste fluid is generated during the blood purification treatment.

[0136] Ratio = Fifth detection temperature / Weight increase rate.

[0137] If the patient's blood is in a normal blood purification treatment process, the fifth detection temperature remains stable, the weight increase rate of the waste fluid bag will also remain stable, and the ratio will also remain stable. If the ratio suddenly increases or decreases, it indicates that the blood temperature in the blood circuit and / or the rate at which waste fluid enters the waste fluid branch has changed drastically. In this embodiment, the ratio between the fifth detection temperature and the weight increase rate is used to determine whether the patient's blood purification treatment process is in a normal state, and the rotation speed of the second peristaltic pump is adjusted based on the ratio between the fifth detection temperature and the weight increase rate, so that the rotation speed of the second peristaltic pump after feedback adjustment affects the weight increase rate of the waste fluid bag and the heat lost by the blood in the blood circuit.

[0138] In this embodiment, the rotation speed of the second peristaltic pump is adjusted based on the ratio between the fifth detected temperature and the weight gain rate. This allows for more comprehensive control of the rotation speed of the second peristaltic pump, ensuring the safety of both blood temperature and blood flow in the blood circuit during the blood treatment phase.

[0139] In some embodiments, step S121, which involves adjusting the rotational speed of the second peristaltic pump based on the ratio, may include:

[0140] Sub-step S1211: If the ratio is greater than the first preset ratio value, then the speed of the second peristaltic pump is increased.

[0141] Sub-step S1212: If the ratio is less than or equal to the second preset ratio value, then reduce the rotational speed of the second peristaltic pump.

[0142] Sub-step S1213: If the ratio is greater than the second preset ratio value and less than or equal to the first preset ratio value, then the rotation speed of the second peristaltic pump is kept constant; wherein, the first preset ratio value is greater than the second preset ratio value.

[0143] Specifically, the first preset ratio value represents the upper limit of the normal range of the ratio (i.e., the ratio between the fifth detection temperature and the weight gain rate), and the second preset ratio value represents the lower limit of the normal range of the ratio. Both the first and second preset ratio values ​​can be determined based on clinical experience, for example, the first preset ratio value is 3.7 and the second preset ratio value is 3.5. The normal range of the ratio is greater than 3.5 and less than or equal to 3.7. When the ratio fluctuates within the normal range, the patient's blood purification treatment process will be in a normal and stable state. In this case, it is only necessary to keep the speed of the second peristaltic pump constant to maintain the safety of the patient's blood purification treatment.

[0144] If the ratio is less than or equal to the second preset ratio value, it indicates that the fifth detection temperature is too low or the weight increase rate is too high. In this case, the speed of the second peristaltic pump needs to be reduced, the waste liquid flow rate in the waste liquid branch will be reduced, the rate at which the waste liquid bag enters the waste liquid will also be reduced, and the heat lost from the blood in the blood circuit will also be reduced. According to the above ratio calculation formula, the ratio will increase until the increased ratio can return to the normal ratio range.

[0145] If the ratio is greater than the first preset ratio value, it indicates that the fifth detection temperature is too high or the weight increase rate is too low. In this case, the speed of the second peristaltic pump needs to be increased, the waste liquid flow rate in the waste liquid branch increases, the rate at which the waste liquid bag enters the waste liquid also increases, and the heat lost from the blood in the blood circuit also increases. According to the above ratio calculation formula, the ratio will decrease until the reduced ratio can return to the normal ratio range.

[0146] It should be noted that there are many ways to increase or decrease the speed of the second peristaltic pump; only one method is listed here: A speed change amount ΔR is pre-selected, for example, ΔR = 2 r / min. If the ratio is greater than a first preset ratio value, the speed of the second peristaltic pump is increased by ΔR until the reduced ratio returns to the normal range. If the ratio is less than or equal to the second preset ratio value, the speed of the second peristaltic pump is decreased by ΔR until the increased ratio returns to the normal range.

[0147] The above only lists one way to increase or decrease the speed of the second peristaltic pump. Of course, there are other methods to increase or decrease the speed of the second peristaltic pump, but these other methods will not be described in detail here.

[0148] This embodiment uses the ratio between the fifth detected temperature and the weight gain rate to adjust the rotational speed of the second peristaltic pump. This feedback adjustment method takes into account both the blood temperature in the blood circuit and the waste liquid flow rate in the waste liquid branch. If either the blood temperature in the blood circuit or the waste liquid flow rate in the waste liquid branch changes abnormally, the calculated ratio between the fifth detected temperature and the weight gain rate will also change abnormally. By adjusting the rotational speed of the second peristaltic pump based on this ratio, both parameters can be changed simultaneously. This ensures that both the blood temperature in the blood circuit and the waste liquid flow rate in the waste liquid branch remain stable and safe, improving the control precision and response accuracy of the feedback adjustment of the second peristaltic pump's rotational speed. For example, if the rotational speed of the second peristaltic pump is adjusted only based on the fifth detected temperature, or only based on the weight gain rate, it will not take into account both the blood temperature in the blood circuit and the waste liquid flow rate in the waste liquid branch, leading to significant errors in the feedback adjustment.

[0149] In some embodiments, in S101, when the blood purification device is in the pre-fluidation test stage, controlling the heating plate to heat the replacement fluid in the fluid replenishment branch may include: setting the initial heating temperature; when the blood purification device is in the pre-fluidation test stage, controlling the heating plate to heat the replacement fluid in the fluid replenishment branch according to the initial heating temperature.

[0150] As described above, during the pre-flush test, the replacement fluid is connected to the infusion branch, and the replacement fluid in the infusion branch is preheated by a heating plate. The initial heating temperature represents the initial heating temperature of the heating plate during the preheating process. During the pre-flush test, the replacement fluid in the infusion branch after heating is not directly output to the blood circuit. Therefore, the initial heating temperature does not need to be set very precisely. Users can choose any suitable initial heating temperature. It is only necessary to control the heating plate to heat the replacement fluid in the infusion branch according to the initial heating temperature, and the temperature of the heated replacement fluid should be within the preset safe temperature range. It should be noted that the set initial heating temperature refers to the heating temperature of the heating plate.

[0151] Once the initial heating temperature is set, during the pre-charge test phase, the heating plate will be controlled to heat at the initial heating temperature, and the heating temperature of the heating plate will remain at the initial heating temperature.

[0152] In some embodiments, the blood purification device further includes: a waste fluid branch, a waste fluid bag, a first weighing sensor, and a second weighing sensor; the first end of the waste fluid branch is connected to the blood circuit, and the second end of the waste fluid branch is connected to the waste fluid bag, which is used to store waste fluid; the first weighing sensor is disposed at the top of the blood purification device, and the replenishment bag is suspended on the first weighing sensor, which is used to weigh the replenishment bag; the second weighing sensor is disposed at the bottom of the blood purification device, and the waste fluid bag is suspended on the second weighing sensor, which is used to weigh the waste fluid bag. During the blood treatment phase, the replenishment bag outputs replacement fluid to the blood circuit through the replenishment branch, and the waste fluid branch outputs waste fluid to the waste fluid bag. The first weighing sensor detects the weight reduction of the replenishment bag, and the second weighing sensor detects the weight increase of the waste fluid bag. Based on the relative magnitude of the weight reduction of the replenishment bag and the weight increase of the waste fluid bag, it is possible to determine whether the patient's body fluids are balanced during the blood purification treatment and to identify the patient's blood purification treatment status.

[0153] At this time, the control method may further include:

[0154] Step S122: When the blood purification device switches to the blood treatment stage, the first weighing sensor is used to weigh the infusion bag to obtain a first weight detection value.

[0155] Step S123: Weigh the waste liquid bag using the second weighing sensor to obtain a second weight detection value.

[0156] Step S124: Plot the first weight detection value as a function of time, which is the first weighing change curve.

[0157] Step S125: Plot the second weight detection value as a function of time, which is the second weighing change curve.

[0158] Step S126: Determine whether the blood purification device has been impacted by an external force based on the degree of difference between the tangent slope of the first weighing change curve and the tangent slope of the second weighing change curve.

[0159] In some embodiments, step S126, determining whether the blood purification device has been impacted by an external force based on the degree of difference between the tangent slope of the first weighing change curve and the tangent slope of the second weighing change curve, may include:

[0160] Sub-step S1261: When the first condition and / or the second condition are met, determine that the blood purification device has been impacted by an external force.

[0161] Sub-step S1262: If the first and second conditions are not met, determine that the blood purification device has not been impacted by an external force.

[0162] The first condition is: |absolute value of the slope of the tangent line of the first weighing change curve - absolute value of the slope of the tangent line of the second weighing change curve| < a first preset value, and |slope of the tangent line of the first weighing change curve| > a second preset value; the second condition is: |absolute value of the slope of the tangent line of the first weighing change curve - absolute value of the slope of the tangent line of the second weighing change curve| < a first preset value, and |slope of the tangent line of the second weighing change curve| > a second preset value.

[0163] Specifically, the slope of the tangent line of the first weighing change curve represents the weight change trend of the replenishment bag, and the slope of the tangent line of the second weighing change curve represents the weight change trend of the waste liquid bag. The absolute values ​​of the tangent lines of the first and second weighing change curves are set. The purpose of setting these absolute values ​​is to allow for a comparison between the two: since the first weight detection value gradually decreases over time, the slope of the tangent line of the first weighing change curve is less than 0; and since the second weight detection value gradually increases over time, the slope of the tangent line of the second weighing change curve is greater than 0. In this embodiment, taking the absolute value of the tangent lines allows for a unified standard to determine the difference in the weight change trends of the replenishment bag and the waste liquid bag.

[0164] If the first condition and / or the second condition are met (i.e., the first condition is met, or the second condition is met, or both the first and second conditions are met), it indicates that the weight change trends of the replenishment bag and the waste bag are synchronized, and the weight of the replenishment bag changes drastically, or the weight of the waste bag changes drastically. In this case, the drastic weight change is because the blood purification equipment is subjected to an external impact, causing the replenishment bag and the waste bag to shake synchronously, resulting in drastic changes in the weighing results of the first and second weighing sensors.

[0165] Conversely, if neither the first nor the second condition is met, it indicates that the weight change trends of the infusion bag and the waste bag are not synchronized, or that neither of them exhibits drastic weight changes. In this case, it can be determined that the blood purification equipment has not been impacted by external forces. For example, if neither the weight of the infusion bag nor the waste bag changes drastically, it means that both the first and second weighing sensors are in normal weighing condition and there has been no external impact. Or, if only one of the infusion bag or the waste bag exhibits a drastic weight change, it indicates that the blood purification equipment has not been impacted by external forces; it is possible that only one of the infusion bag or the waste bag is shaking, leading to a drastic weight change in only one of them (because multiple experiments have verified that if the blood purification equipment is impacted by external forces, the weights of both the infusion bag and the waste bag attached to the blood purification equipment will change drastically).

[0166] Both the first and second preset values ​​can be pre-set based on clinical experience. The first preset value is used to determine whether the weight change trends of the infusion bag and the waste bag are synchronized. The second preset value is used to determine whether there are drastic changes in the weight of the infusion bag or the waste bag. For example, the first preset value = 0.6 and the second preset value = 0.8.

[0167] This embodiment uses the weighing detection results of the first weighing sensor and the second weighing sensor to make a dual judgment on whether the blood purification equipment has been impacted by an external force, thereby reducing the judgment error of whether the blood purification equipment has been impacted by an external force.

[0168] In some embodiments, the blood purification device further includes a second peristaltic pump, which is disposed on the waste liquid branch and is used to control the waste liquid branch to output the waste liquid generated by the blood circuit to the waste liquid bag.

[0169] At this point, sub-step S1261, which determines that the blood purification device has been impacted by an external force when the first condition and / or the second condition are met, may further include:

[0170] Sub-step S12611: When the blood purification device switches to the blood treatment stage, start recording the cumulative operating time of the first peristaltic pump and the cumulative operating time of the second peristaltic pump.

[0171] It should be noted that "cumulative operating time" is an accumulated quantity. For example, when the first peristaltic pump stops and then restarts, its cumulative operating time will not be reset to zero. Instead, it will be the sum of all the operating times of the first peristaltic pump. When the blood purification equipment switches from the pre-flushing test stage to the blood treatment stage, the first and second peristaltic pumps operate synchronously. The cumulative operating time of the first peristaltic pump represents the cumulative time that the fluid replacement branch outputs replacement fluid to the blood circuit, and the cumulative operating time of the second peristaltic pump represents the cumulative time that the waste fluid branch outputs waste fluid to the waste fluid bag.

[0172] Sub-step S12612: When the cumulative operating time of the first peristaltic pump is greater than the cumulative operating time of the second peristaltic pump, and the first condition is met, it is determined that the blood purification device has been impacted by an external force.

[0173] When the cumulative operating time of the first peristaltic pump is greater than that of the second peristaltic pump, and the cumulative operating time of the replacement fluid output from the replenishment bag is greater than that of the waste fluid receiving bag, then the blood purification equipment can be judged by whether there is a drastic change in the weight of the replenishment bag. This is because when the cumulative operating time of the replacement fluid output from the replenishment bag is greater than that of the waste fluid receiving bag, the change in the weight of the replenishment bag has higher reference value. Therefore, the change in the weight of the replenishment bag can be used to more accurately determine whether the blood purification equipment has been impacted by an external force.

[0174] Sub-step S12613: When the cumulative operating time of the first peristaltic pump is less than the cumulative operating time of the second peristaltic pump, and the second condition is met, it is determined that the blood purification device has been impacted by an external force.

[0175] If the cumulative operating time of the first peristaltic pump is less than the cumulative operating time of the second peristaltic pump, and the cumulative time of the replacement fluid output from the replenishment bag is less than the cumulative time of the waste fluid receiving bag, then it can be determined whether the blood purification equipment has been impacted by an external force based on whether the weight of the waste fluid bag changes drastically.

[0176] Sub-step S11614: When the cumulative operating time of the first peristaltic pump is equal to the cumulative operating time of the second peristaltic pump, and the first condition and the second condition are met, it is determined that the blood purification device has been impacted by an external force.

[0177] When the cumulative operating time of the first peristaltic pump equals the cumulative operating time of the second peristaltic pump, and the cumulative time of the replacement fluid output from the replenishment bag equals the cumulative time of the waste fluid receiving bag, it is necessary to simultaneously determine whether the blood purification equipment has been impacted by external force based on whether the weight of the waste fluid bag and the weight of the replenishment bag have changed drastically. This greatly improves the accuracy of determining whether the blood purification equipment has been impacted by external force during the blood treatment stage.

[0178] It should be noted that during blood therapy, the operation of both the first and second peristaltic pumps is determined based on the patient's clinical needs. For example, if the user determines that the patient does not require replacement fluid for a certain period, the first peristaltic pump will be stopped, halting the fluid replacement pathway. After this period, the first peristaltic pump will be restarted. Similarly, when there is flowing blood in the blood circuit, the circuit purifies the patient's blood. If the purification efficiency is low, resulting in minimal waste fluid, the second peristaltic pump will stop for a period before restarting. Therefore, during blood therapy, there is a relative relationship between the cumulative operating time of the first and second peristaltic pumps. This embodiment distinguishes the relative magnitudes of the cumulative operating time of the first peristaltic pump and the cumulative operating time of the second peristaltic pump, and uses different judgment conditions to determine whether the blood purification equipment has been impacted by an external force. This makes the judgment of the blood purification equipment being impacted by an external force more accurate and reduces the judgment error.

[0179] It should be noted that when the cumulative operating time of the first peristaltic pump is greater than the cumulative operating time of the second peristaltic pump, the second condition is met but the first condition is not met, and it is determined that the blood purification equipment has not been impacted by an external force.

[0180] When the cumulative operating time of the first peristaltic pump is less than the cumulative operating time of the second peristaltic pump, the first condition is met but the second condition is not met, and it is determined that the blood purification equipment has not been impacted by an external force.

[0181] When the cumulative operating time of the first peristaltic pump is equal to the cumulative operating time of the second peristaltic pump, the first condition is met but the second condition is not met, or the second condition is met but the first condition is not met, then it is determined that the blood purification equipment has not been impacted by an external force.

[0182] In some embodiments, when the blood purification device switches to the blood treatment stage, the control method further includes:

[0183] Step S127: Weigh the replenishment bag using the first weighing sensor to obtain the cumulative weight reduction value of the replenishment bag.

[0184] Step S128: Weigh the waste liquid bag using the second weighing sensor to obtain the cumulative weight increase of the waste liquid bag.

[0185] Step S129: When the absolute value of the difference between the cumulative weight reduction of the replenishment bag and the cumulative weight increase of the waste bag is greater than the preset weight safety value, control both the first peristaltic pump and the second peristaltic pump to stop operating.

[0186] Specifically, the cumulative weight reduction value represents the total amount of replacement fluid output from the rehydration line to the blood circuit during the blood therapy phase. The cumulative weight increase value represents the total amount of waste fluid output from the blood circuit to the waste bag during the blood therapy phase. If the patient's body fluids are in equilibrium, the cumulative weight reduction value of the rehydration bag and the cumulative weight increase value of the waste bag will be in equilibrium. The total amount of waste fluid lost from the patient's blood and the total amount of replacement fluid replenished into the patient's blood will remain in equilibrium, that is: |cumulative weight reduction value of the rehydration bag - cumulative weight increase value of the waste bag| ≤ preset safety weight value.

[0187] When the cumulative weight reduction of the replacement fluid bag minus the cumulative weight increase of the waste fluid bag exceeds the preset safe weight value, the total amount of waste fluid lost from the patient's blood and the total amount of replacement fluid replenished into the patient's blood are out of balance. This means either too much fluid is lost from the patient's blood or too much fluid is replenished into the patient's blood. In this situation, it is necessary to stop both the first and second peristaltic pumps to terminate the patient's blood purification treatment. This prevents the patient from continuing blood purification treatment while in a state of fluid imbalance, thus compromising the safety of the blood purification treatment.

[0188] The preset weight safety value represents the allowable error in the absolute value of the difference between the total amount of waste fluid lost and the total amount of replacement fluid replenished during blood therapy. The preset weight safety value can be set based on clinical experience, for example, the preset weight safety value = 300g. When |cumulative weight reduction of the replacement bag - cumulative weight increase of the waste bag| ≤ 300g, the difference between the total amount of waste fluid lost from the patient's blood and the total amount of replacement fluid replenished into the patient's blood is within the user's allowable error range, and the patient's body fluids are in a state of equilibrium. If the cumulative weight decrease of the infusion bag minus the cumulative weight increase of the waste fluid bag > 300g, the difference between the total amount of waste fluid lost from the patient's blood and the total amount of replacement fluid replenished into the patient's blood exceeds the user-allowed error range, indicating that the patient's body fluids are in a state of imbalance. If the cumulative weight decrease of the infusion bag minus the cumulative weight increase of the waste fluid bag > 300g, it indicates that too much fluid has been replenished into the patient's blood. If the cumulative weight increase of the waste fluid bag minus the cumulative weight decrease of the infusion bag > 300g, it indicates that the total amount of waste fluid lost from the patient's blood is too much.

[0189] It should be noted that the sequence numbers of the above steps (such as S101, S102, etc.) are only used to refer to each step and do not mean that the steps in this embodiment will be executed in the order of the sequence numbers. The steps in this embodiment will be executed in the logical order of the technical solution.

[0190] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, causes the processor to implement the control method for the blood purification device as described above. For detailed descriptions of the related content, please refer to the relevant content of the above methods, which will not be repeated here.

[0191] The computer-readable storage medium can be an internal storage unit of the aforementioned blood purification device, such as a hard drive or memory. Alternatively, it can be an external storage device, such as an external hard drive, smart memory card, secure digital card, flash memory card, etc.

[0192] It should be understood that the terminology used in this application specification is for the purpose of describing particular embodiments only and is not intended to limit the application.

[0193] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0194] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and such modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A blood purification device, characterized in that, The blood purification device includes: a first temperature sensor, a second temperature sensor, a first peristaltic pump, a heating plate, a blood circuit, a fluid resuscitation branch, and a fluid resuscitation bag; the blood circuit is connected between the patient's artery and vein; the first end of the fluid resuscitation branch is connected to the fluid resuscitation bag, and the second end of the fluid resuscitation branch is connected to the blood circuit; the heating plate is disposed on the fluid resuscitation branch; the first peristaltic pump is disposed on the fluid resuscitation branch; the first temperature sensor is disposed at the inlet of the heating plate; the second temperature sensor is disposed at the outlet of the heating plate; the fluid resuscitation bag is used to store replacement fluid; and the first peristaltic pump is used to control the fluid resuscitation branch to output replacement fluid to the blood circuit; the blood purification device further includes: a memory and a processor; the memory is used to store a computer program; and the processor is used to execute the computer program and, when executing the computer program, implement the following control method for the blood purification device: When the blood purification device is in the pre-flushing test stage, the heating plate is controlled to heat the replacement fluid in the fluid infusion branch. The second temperature sensor is used to detect the temperature of the replacement fluid in the fluid infusion branch to obtain the first detection temperature. When the first detection temperature is within the preset safe temperature range, the blood purification device is controlled to switch to the blood treatment stage. When the blood purification device switches to the blood treatment stage, it controls the heating plate to start heating the replacement fluid in the fluid infusion branch according to the preset initial heating temperature, receives the heating target temperature set by the user, detects the rotation speed of the first peristaltic pump, and obtains the first flow rate of the fluid infusion branch according to the rotation speed of the first peristaltic pump. A temperature lookup table is determined based on the first flow rate, wherein the temperature lookup table includes the correspondence between the temperature of the displacement fluid and the heating temperature of the heating plate; The heating temperature of the heating plate is found in the temperature lookup table according to the target heating temperature, and is used as the first heating temperature of the heating plate. The actual heating temperature of the heating plate is detected, and the heating power of the heating plate is adjusted by PID feedback based on the actual heating temperature and the first heating temperature.

2. The blood purification device according to claim 1, characterized in that, When the heating power of the heating plate is adjusted using PID feedback based on the actual heating temperature and the first heating temperature, the processor executes the computer program and, while executing the computer program, implements the following control method for the blood purification device: The temperature of the replacement fluid in the replenishment branch is detected using the first temperature sensor to obtain the second detection temperature; The temperature of the replacement fluid in the replenishment branch is detected using the second temperature sensor to obtain the third detection temperature; When the absolute value of the temperature difference between the second detection temperature and the third detection temperature is less than the preset start-up difference, a first alarm signal is issued.

3. The blood purification device according to claim 1, characterized in that, The processor is used to execute the computer program and, when executing the computer program, to implement the following control method for the blood purification device: A PID controller is set up, and the parameters of the PID controller are tuned. The first heating temperature is used as the input of the PID controller, the actual heating temperature is used as the feedback of the PID controller, and the heating power of the heating plate is used as the adjustment of the PID controller. Specifically, the parameter tuning of the PID controller includes: When the blood purification device is switched to the blood treatment stage, the flow time of the replacement fluid from the inlet of the heating plate to the outlet of the heating plate is detected; The parameters of the PID controller are tuned based on the flow time.

4. The blood purification device according to claim 1, characterized in that, The blood purification device further includes: a third temperature sensor, a fourth temperature sensor, a second peristaltic pump, a waste liquid branch, and a waste liquid bag; the first end of the waste liquid branch is connected to the blood circuit, the second end of the waste liquid branch is connected to the waste liquid bag, the second peristaltic pump is disposed on the waste liquid branch, the fourth temperature sensor is disposed on the blood circuit, the third temperature sensor is disposed on the waste liquid bag, the waste liquid bag is used to store waste liquid, and the second peristaltic pump is used to control the waste liquid branch to output the waste liquid generated by the blood circuit to the waste liquid bag; the processor is used to execute the computer program and, when executing the computer program, implement the following control method for the blood purification device: When the blood purification device switches to the blood treatment stage, the rotational speed of the second peristaltic pump is detected; The third temperature sensor is used to detect the temperature of the waste liquid inside the waste liquid bag to obtain the fourth detection temperature; The fourth temperature sensor is used to detect the blood temperature in the blood circuit to obtain the fifth detection temperature; The temperature of the replacement fluid in the replenishment branch is detected using the second temperature sensor to obtain the third detection temperature; When the difference between the fourth and third detected temperatures is greater than the product of the fifth detected temperature multiplied by the first preset percentage, a second alarm signal is issued; when the difference between the third and fourth detected temperatures is greater than the product of the fifth detected temperature multiplied by the second preset percentage, a third alarm signal is issued; when the difference between the fourth and third detected temperatures is less than or equal to the product of the fifth detected temperature multiplied by the first preset percentage, and the difference between the third and fourth detected temperatures is less than or equal to the product of the fifth detected temperature multiplied by the second preset percentage, a curve showing the change in the rotational speed of the second peristaltic pump versus the fourth detected temperature is plotted.

5. The blood purification device according to claim 4, characterized in that, The blood purification device further includes: a second weighing sensor; the second weighing sensor is disposed at the bottom of the blood purification device, the waste liquid bag is suspended on the second weighing sensor, and the second weighing sensor is used to weigh the waste liquid bag; The processor is used to execute the computer program and, when executing the computer program, to implement the following control method for the blood purification device: Plot the temperature change curve of the fifth detection temperature over time; The waste liquid bag is weighed using the second weighing sensor to obtain a second weight detection value; The fifth detection temperature is checked to see if it is within a preset normal temperature range, which is set according to the patient's physiological characteristic parameters; When the fifth detected temperature is not within the normal temperature range, a fourth alarm signal is issued; When the fifth detection temperature is within the normal temperature range, the weight increase rate of the waste liquid bag is calculated based on the second weight detection value, the ratio between the fifth detection temperature and the weight increase rate is calculated, and the rotation speed of the second peristaltic pump is adjusted based on the ratio.

6. The blood purification device according to claim 5, characterized in that, The processor is used to execute the computer program and, when executing the computer program, to implement the following control method for the blood purification device: If the ratio is greater than the first preset ratio value, the speed of the second peristaltic pump will be increased; If the ratio is less than or equal to the second preset ratio value, the rotational speed of the second peristaltic pump will be reduced. If the ratio is greater than the second preset ratio value and less than or equal to the first preset ratio value, then the rotational speed of the second peristaltic pump will be kept constant. Wherein, the first preset ratio value is greater than the second preset ratio value.

7. The blood purification device according to claim 1, characterized in that, The blood purification device further includes: a waste liquid branch, a waste liquid bag, a first weighing sensor, and a second weighing sensor; the first end of the waste liquid branch is connected to the blood circuit, and the second end of the waste liquid branch is connected to the waste liquid bag, which is used to store waste liquid; the first weighing sensor is located at the top of the blood purification device, and the replenishment bag is suspended on the first weighing sensor, which is used to weigh the replenishment bag; the second weighing sensor is located at the bottom of the blood purification device, and the waste liquid bag is suspended on the second weighing sensor, which is used to weigh the waste liquid bag. The processor is used to execute the computer program and, when executing the computer program, to implement the following control method for the blood purification device: When the blood purification device switches to the blood treatment stage, the first weighing sensor is used to weigh the infusion bag to obtain a first weight detection value. The waste liquid bag is weighed using the second weighing sensor to obtain a second weight detection value; Plot the first weight detection value as a function of time, resulting in a first weighing change curve. Plot the second weighing curve of the second weight detection value over time; The degree of difference between the tangent slope of the first weighing change curve and the tangent slope of the second weighing change curve determines whether the blood purification device has been impacted by an external force. Determining whether the blood purification equipment has been impacted by an external force based on the degree of difference between the tangent slopes of the first and second weighing change curves includes: When the first condition and / or the second condition are met, it is determined that the blood purification device has been impacted by an external force. If the first and second conditions are not met, it is determined that the blood purification device has not been impacted by an external force. The first condition is: |absolute value of the slope of the tangent line of the first weighing change curve - absolute value of the slope of the tangent line of the second weighing change curve| < the first preset value, and |slope of the tangent line of the first weighing change curve| > the second preset value; The second condition is: |absolute value of the slope of the tangent line of the first weighing change curve - absolute value of the slope of the tangent line of the second weighing change curve| < the first preset value, and |slope of the tangent line of the second weighing change curve| > the second preset value.

8. The blood purification device according to claim 7, characterized in that, The blood purification device further includes: a second peristaltic pump, which is disposed on the waste liquid branch and is used to control the waste liquid branch to output the waste liquid generated by the blood circuit to the waste liquid bag; The processor is used to execute the computer program and, when executing the computer program, to implement the following control method for the blood purification device: When the blood purification device switches to the blood treatment stage, it begins to record the cumulative operating time of the first peristaltic pump and the cumulative operating time of the second peristaltic pump. When the cumulative operating time of the first peristaltic pump is greater than the cumulative operating time of the second peristaltic pump, and the first condition is met, it is determined that the blood purification device has been impacted by an external force. When the cumulative operating time of the first peristaltic pump is less than the cumulative operating time of the second peristaltic pump, and the second condition is met, it is determined that the blood purification device has been impacted by an external force. When the cumulative operating time of the first peristaltic pump is equal to the cumulative operating time of the second peristaltic pump, and the first and second conditions are met, it is determined that the blood purification device has been impacted by an external force.

9. The blood purification device according to claim 7, characterized in that, The blood purification device further includes: a second peristaltic pump, which is disposed on the waste liquid branch and is used to control the waste liquid branch to output the waste liquid generated by the blood circuit to the waste liquid bag; When the blood purification device switches to the blood treatment stage, the processor executes the computer program and, while executing the computer program, implements the following control method for the blood purification device: The first weighing sensor is used to weigh the replenishment bag to obtain the cumulative weight reduction value of the replenishment bag; The waste liquid bag is weighed using the second weighing sensor to obtain the cumulative weight increase of the waste liquid bag; When the absolute value of the difference between the cumulative weight decrease of the replenishment bag and the cumulative weight increase of the waste bag is greater than a preset weight safety value, both the first peristaltic pump and the second peristaltic pump are controlled to stop operating.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, causes the processor to implement the control method of the blood purification device as described in any one of claims 1-9.

Images