Hemodialysis apparatus dialysate filter monitoring system

Abstract

The application discloses a hemodialysis equipment dialysate filter monitoring system and belongs to the field of medical devices. The system collects pressure fluctuation data generated by the periodic work of the balance cavity in the waterway balance system in real time, calculates a characteristic parameter (such as a pressure change rate) representing the pressure fluctuation amplitude, compares the characteristic parameter with a preset threshold value, and combines a jitter prevention counting logic to determine that the dialysate filter is blocked when a plurality of continuous periods meet the blocking condition. The application can dynamically and real-timely monitor the filter blocking state during the whole process of equipment self-checking and patient treatment without adding additional hardware, can early warn the flow abnormality caused by filter blocking, can guarantee treatment accuracy and patient safety, and can effectively avoid false alarms caused by single measurement errors.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a dialysate filter monitoring system for hemodialysis equipment, and more particularly to a system for real-time monitoring of the clogging status of dialysate filters in hemodialysis equipment. Background Technology

[0002] Hemodialysis is one of the main medical treatments for patients with end-stage renal disease. The water balance system of a hemodialysis machine is a core component that ensures the safety and stability of dialysis treatment. It typically relies on the balance chamber assembly to achieve volume balance of circulating blood outside the body. As a key component of the balance system, the dialysate filter's main function is to filter bacteria, endotoxins, and microparticles from the dialysate, preventing them from entering the patient's bloodstream. This is a crucial barrier to ensuring treatment safety.

[0003] Currently, the management of dialysis fluid filters mainly focuses on two aspects: firstly, during the equipment self-inspection phase or after installing a new filter, pressure testing is conducted by inflating the filter and observing the pressure drop to determine if there are major defects such as membrane rupture; secondly, the lifespan of the filter is managed according to the preset dialysis duration or number of dialysis sessions, reminding the user to replace it when it expires. These methods all target the filter's "endpoint" or "static" state and cannot dynamically monitor the filter's operational status during patient treatment.

[0004] However, another risk exists in clinical practice: due to abnormal upstream water quality, dialysate crystallization, or prolonged use, the dialysate filter may become progressively clogged, leading to a significant reduction in its flux. Filter clogging can cause abnormal water pressure, resulting in the dialysate or replacement fluid flow rate supplied to the dialyzer falling below the set value. Especially in hemodialysis filtration (HDF) treatment mode, this can lead to insufficient replacement fluid being added to the patient's blood, while the ultrafiltration system continues to operate according to the set dehydration target, resulting in the patient's actual dehydration volume far exceeding the prescribed target, severely affecting treatment accuracy and potentially endangering the patient's life. Existing hemodialysis equipment lacks real-time monitoring methods for this dynamic clogging state. Once such an anomaly occurs, the system often struggles to identify the specific cause in a timely manner, or although it may issue a vague alarm (such as "water path abnormality"), it cannot accurately pinpoint dialysate filter clogging.

[0005] Therefore, there is an urgent clinical need for a system that can monitor the dynamic operating status (especially the blockage status) of the dialysate filter in real time and accurately during the operation of hemodialysis equipment, especially during patient treatment, without adding complex hardware. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a dialysate filter monitoring system for hemodialysis equipment, which dynamically determines the clogging status by analyzing pressure fluctuation characteristic parameters, thereby solving the problem that the existing technology cannot monitor filter clogging in real time and accurately, and ensuring treatment safety and accuracy.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A dialysate filter monitoring system for a hemodialysis device is applied to the water balance system of the hemodialysis device. The water balance system includes an inlet pump, a balance chamber assembly, a dialysate filter, and an outlet pump. The inlet pump, the dialysate channel of the balance chamber assembly, and the dialysate filter are connected sequentially for supplying dialysis fluid to the extracorporeal blood purification system. The outlet pump is used to discharge dialysis waste fluid flowing out of the extracorporeal blood purification system through the dialysis waste fluid channel of the balance chamber assembly. A raw fluid branch is provided between the dialysate filter and the downstream side of the extracorporeal blood purification system. The dialysate filter monitoring system includes: The pressure detection unit includes an inlet pressure sensor located upstream of the dialysate filter and / or an outlet pressure sensor located downstream of the dialysate filter. The main control unit, electrically connected to the pressure detection unit, is configured to perform the following steps: Step 1: During the self-test phase and / or operation of the hemodialysis equipment, pressure data of the water balance system is continuously collected by a pressure sensor at a set sampling interval within each preset detection cycle, using a preset detection cycle as the time unit; the pressure sensor is the inlet pressure sensor and / or the outlet pressure sensor. Step Two: At the end of each testing cycle, based on all pressure data collected during that cycle, calculate the characteristic parameters used to characterize the pressure fluctuation amplitude during that cycle; the characteristic parameters include the pressure change rate, which is calculated as follows:

[0008]

[0009] in: This represents the rate of change of pressure. The difference between the maximum and minimum pressure values ​​within the detection cycle; The duration of the detection cycle; and These are the maximum and minimum pressure values ​​within the testing period, respectively. Step 3: Compare the feature parameters with the preset blockage determination threshold to determine whether the feature parameters meet the preset blockage conditions: if yes, increment the blockage count and proceed to Step 4; if no, clear the blockage count and proceed to Step 1. Step 4: Determine whether the cumulative value of the blockage count has reached the preset continuous anti-shake count threshold: if yes, then determine that the dialysate filter is blocked; if no, then repeat Step 1.

[0010] Furthermore, in step three, if the pressure change rate Less than the preset pressure change rate threshold This indicates abnormal pressure fluctuations in the current detection cycle, and an additional blockage count is added; if the pressure change rate... Greater than or equal to the preset pressure change rate threshold If the pressure fluctuation is normal during the current detection cycle, the blockage count will be reset to zero.

[0011] Furthermore, the pressure change rate threshold Set to 5~8 kPa / s.

[0012] Furthermore, the characteristic parameter also includes a pressure difference value, which is calculated as follows:

[0013]

[0014] in: This is the pressure difference; This represents the maximum pressure value within the detection cycle. This is the average value of all pressure data within the detection period; The first sample collected within the detection cycle One pressure data point; This refers to the number of pressure data collected during the detection period.

[0015] Furthermore, in step three, if the pressure difference... less than the preset pressure difference threshold This indicates abnormal pressure fluctuations in the current detection cycle, and an additional blockage count is added; if the pressure difference is... Pressure difference greater than or equal to the preset threshold value If the pressure fluctuation is normal during the current detection cycle, the blockage count will be reset to zero.

[0016] Furthermore, the pressure difference threshold Set to 3~6 kPa.

[0017] Furthermore, the duration of the detection cycle is configured to cover at least one complete working cycle of the balance cavity assembly; And / or, The range of the continuous stabilization count threshold is 3 to 5 times.

[0018] Furthermore, when it is determined that the dialysate filter is clogged, an audible and visual alarm is triggered, and the time and pressure data of the clog occurrence are recorded; And / or, If the dialysate filter is determined to be clogged during the operation of the hemodialysis equipment, treatment protection measures are implemented.

[0019] Furthermore, the dialysate filter includes a primary filter and a secondary filter connected in series and located upstream of the extracorporeal blood purification system. The primary filter is located upstream of the secondary filter. The inlet chambers of the primary filter and the secondary filter are respectively provided with a first branch and a second branch between themselves and the downstream side of the extracorporeal blood purification system. A first solenoid valve and a second solenoid valve are respectively provided on the first branch and the second branch. A third solenoid valve and a fourth solenoid valve are respectively provided at the inlet and outlet ends of the extracorporeal blood purification system. During the self-test phase of the hemodialysis equipment, if the dialysate filter is found to be clogged, a filter clogging judgment is also performed. The method is as follows: close the first, third, and fourth solenoid valves, open the second solenoid valve, and execute steps one to four. If the judgment result is that the filter is clogged, then the primary filter is clogged; otherwise, the secondary filter is clogged.

[0020] Furthermore, it also includes an alarm unit, which is used to trigger an audible and visual alarm when the dialysate filter is determined to be clogged, and to record the time and pressure data of the clog occurrence through the main control unit.

[0021] The beneficial effects of this invention are as follows: The dialysate filter monitoring system for hemodialysis equipment of the present invention continuously collects pressure data of the water balance system at a preset detection cycle during the self-test and operation of the hemodialysis equipment, calculates characteristic parameters characterizing the pressure fluctuation amplitude, and combines anti-shake counting logic to achieve real-time, dynamic monitoring of the dialysate filter blockage status. Specifically, compared with the existing technology that can only perform static pressure holding tests before treatment or rely solely on usage time for lifespan management, the present invention achieves the following technical advantages: (1) Real-time dynamic monitoring: It can monitor the status of the dialysis fluid filter in real time during the patient's treatment process, and promptly capture the gradual blockage caused by abnormal water quality or crystallization, thus solving the blind spot that the existing technology cannot provide early warning during operation; (2) Improve early warning sensitivity: By analyzing the attenuation characteristics of pressure fluctuation amplitude, it is possible to make a judgment in the early stage of blockage, avoid the deviation of treatment accuracy due to abnormal flow, and ensure the dialysis effect and patient safety. (3) Enhance the system’s anti-interference capability: The introduction of “anti-shake counting” logic effectively avoids false alarms caused by single measurement or accidental pressure fluctuations, and significantly improves the reliability and accuracy of monitoring results; (4) Low cost and easy to implement: It can directly utilize the existing pressure sensors and control units of the equipment without adding extra hardware, and is easy to upgrade or integrate on existing equipment.

[0022] In summary, this invention effectively solves the technical challenge of online dynamic monitoring of dialysate filters, providing a safer, more accurate, and reliable means of ensuring hemodialysis treatment. Attached Figure Description

[0023] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the following figures are provided for illustration: Figure 1 This is a schematic diagram of the water balance system. Figure 2 This is a schematic diagram of the structure of the balance chamber assembly; Figure 3 A flowchart of the steps executed by the main control unit; Figure 4 This is a graph showing the pressure changes on the inlet side during normal treatment. Figure 5 This is a graph showing the pressure changes on the inlet side when the system is blocked.

[0024] Explanation of reference numerals in the attached figures: 10-Dialysis fluid preparation module; 11-Inlet pump; 12-Balance chamber assembly; 121-Balance chamber; 122-Flexible dialysis membrane; 123-Dialysis fluid chamber; 124-Dialysis waste fluid chamber; 13-Primary filter; 131-First branch; 132-First solenoid valve; 14-Secondary filter; 141-Second branch; 142-Second solenoid valve; 15-Extracorporeal blood purification system; 151-Third solenoid valve; 152-Fourth solenoid valve; 16-Outlet pump; 17-Dialysis waste fluid discharge module; 18-Inlet pressure sensor; 19-Outlet pressure sensor. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0026] Hemodialysis uses a dialyzer to purify blood, replacing damaged kidneys. Currently, clinically used dialyzers generally use hollow fiber membranes as the filter. Based on membrane flux, pore size, and molecular weight cutoff, they are classified as dialyzers or hemodialysis filters. A dialyzer is divided into a blood chamber and a dialysate chamber by a hollow fiber membrane. Dialysate and the patient's blood flow in opposite directions across the hollow fiber membrane. Utilizing the principles of diffusion, convection, and ultrafiltration, toxins in the patient's blood cross the membrane and enter the dialysis waste fluid, thus being excreted. The blood chamber is connected to the patient's blood system via extracorporeal circulation tubing, forming an extracorporeal circulation loop, allowing purified blood to return to the body. The dialysate chamber is connected to the hemodialysis equipment's dialysate tubing and dialysis waste fluid tubing. Fresh dialysate supplied by the hemodialysis equipment enters the dialyzer through the dialysate tubing, while dialysis waste fluid flowing out of the dialyzer returns to the hemodialysis equipment through the dialysis waste fluid tubing. The balance of incoming and outgoing fluids is managed by the internal water balance system of the hemodialysis equipment. In addition, the dialysis fluid that has undergone two stages of filtration is generally called replacement fluid. It has a very high purity and can be directly injected into the extracorporeal blood circulation circuit to enter the human body. Then, through the action of the ultrafiltration pump of the hemodialysis equipment, the fluid containing toxins is transported across the membrane from the blood to the dialysis waste fluid and discharged. This process is called filtration therapy.

[0027] The extracorporeal blood purification system 15 of this invention includes a dialyzer and an extracorporeal blood circulation pipeline connected thereto. The inlet of the extracorporeal blood purification system 15 refers to the dialysate inlet of the dialyzer, and may also include a replacement fluid interface of the extracorporeal blood circulation pipeline, through which the replacement fluid is injected into the extracorporeal blood flow path and flows through the blood chamber of the dialyzer. The outlet refers to the dialysis waste fluid outlet of the dialyzer, through which the dialysis waste fluid is discharged and returned to the water balance system. The dialysis fluids of this invention include dialysate and replacement fluid.

[0028] The complete process of hemodialysis treatment generally includes the following stages: hemodialysis equipment startup self-test, installation of the extracorporeal blood purification system 15, pre-filling preparation, blood priming, treatment, blood return, and equipment draining and disinfection. In the pre-filling preparation stage, the hemodialysis equipment is pre-filled and vented by injecting dialysate or replacement fluid into the dialyzer and extracorporeal blood circulation tubing. In the blood priming stage, the arterial end of the extracorporeal blood circulation tubing is connected to the patient's fistula artery, and the venous end is connected to the patient's fistula vein, drawing the patient's blood into the extracorporeal blood circulation tubing and the blood chamber of the dialyzer to establish an extracorporeal circulation loop. In the treatment stage, hemodialysis or diafiltration is performed. The blood return stage, i.e., the patient's discharge stage, involves injecting replacement fluid to push the blood in the extracorporeal blood circulation loop back into the patient's body. The operation of the hemodialysis equipment as described in this invention refers to the processes of pre-filling preparation, blood priming, treatment, and blood return.

[0029] This embodiment aims to propose a dialysate filter monitoring system for hemodialysis equipment, which is applied to the water balance system of hemodialysis equipment. Its core is to use the inherent pressure fluctuation characteristics generated by the periodic operation of the water balance system to determine the clogging status of the dialysate filter in real time.

[0030] like Figure 1 As shown, in this embodiment, the water balance system includes a dialysate preparation module 10, an inlet pump 11, a balance chamber assembly 12, a dialysate filter, an extracorporeal blood purification system 15, an outlet pump 16, and a dialysis waste discharge module 17. The inlet pump 11, the dialysate channel of the balance chamber assembly 12, and the dialysate filter are connected sequentially to supply dialysis fluid to the extracorporeal blood purification system. The outlet pump 16 is used to discharge the dialysis waste flowing out of the extracorporeal blood purification system through the dialysis waste channel of the balance chamber assembly 12. A raw material branch is provided between the dialysate filter and the downstream side of the extracorporeal blood purification system.

[0031] The dialysate filter includes a primary filter 13 and a secondary filter 14 connected in series. The primary filter 13 is located upstream of the secondary filter 14, and both the primary filter 13 and the secondary filter 14 are located upstream of the extracorporeal blood purification system 15. For self-checking to locate blockages, this embodiment includes a first branch 131 and a second branch 141, referred to as the raw fluid branch, which allows the liquid entering the dialysate filter to be directly discharged to the dialysis waste channel without passing through the membrane filter. One end of the first branch 131 is connected to the inlet chamber of the primary filter 13, and the other end is connected to the inlet side of the outlet pump 16. A first solenoid valve 132 is installed on the first branch 131. One end of the second branch 141 is connected to the inlet chamber of the secondary filter 14, and the other end is also connected to the inlet side of the outlet pump 16. A second solenoid valve 142 is installed on the second branch 141. A third solenoid valve 151 and a fourth solenoid valve 152 are respectively installed at the inlet and outlet ends of the extracorporeal blood purification system 15.

[0032] During normal operation, liquid is pushed into the balance chamber assembly 12 by the inlet pump 11. The first solenoid valve 132 in the first branch 131 and the second solenoid valve 142 in the second branch 141 are closed. After the liquid passes through the dialysate filter and completes transmembrane filtration, the third solenoid valve 151 and the fourth solenoid valve 152 open, and the liquid flows through the extracorporeal blood purification system 15, finally being discharged by the outlet pump 16. Dialysis fluid and / or replacement fluid are introduced into the blood purifier through the extracorporeal blood purification system 15, and then the dialysis waste fluid is discharged. Both the dialysate generated from the dialysate preparation system and the dialysis waste fluid returned from the extracorporeal blood purification system 15 flow through the balance chamber assembly 12. The balance of inlet and outlet fluids is achieved by controlling the capacity of the balance chamber. Figure 2As shown, the balancing chamber assembly 12 includes two balancing chambers 121. Each balancing chamber 121 includes a dialysate chamber 123 and a dialysis waste fluid chamber 124 separated by a flexible dialysis membrane 122. When one of the balancing chambers 121 is filled with liquid, it pushes the flexible dialysis membrane 122 to deflect towards the dialysis waste fluid chamber 124, increasing the volume of the dialysate chamber 123 and decreasing the volume of the dialysis waste fluid chamber 124, thus discharging the dialysis waste fluid. The two balancing chambers 121 alternately perform filling and draining operations, realizing continuous liquid intake and output to the extracorporeal blood purification system 15. Specifically, when the dialysate filter of the water circuit balancing system is working normally, the liquid flows smoothly across the membrane. The inlet pump 11 and the outlet pump 16 push the liquid to generate obvious periodic pressure fluctuations (due to the periodic filling and draining characteristics of the balancing chamber assembly 12, the pressure exhibits regular fluctuations, such as...). Figure 4 (As shown in the example); when the dialysate filter becomes clogged, the fluid flow is impeded, and the pressure fluctuation amplitude is significantly reduced (e.g.) Figure 5 (As shown in the example), or even tend to stabilize. By monitoring and analyzing the characteristics of pressure fluctuations, the clogging status of the dialysate filter can be accurately determined.

[0033] Specifically, the dialysate filter monitoring system of the hemodialysis equipment in this embodiment includes a pressure detection unit, a main control unit, and an alarm unit. The pressure detection unit includes an inlet pressure sensor 18 located upstream of the dialysate filter and / or an outlet pressure sensor 19 located downstream of the dialysate filter. The main control unit is electrically connected to the pressure detection unit. The alarm unit is used to trigger an audible and visual alarm when it is determined that the dialysate filter is clogged.

[0034] like Figure 1 As shown, in this embodiment, an inlet pressure sensor 18 and an outlet pressure sensor 19 are respectively provided on the upstream and downstream sides of the extracorporeal blood purification system 15. The pressure data collected by the inlet pressure sensor 18 and the outlet pressure sensor 19 can corroborate each other. That is, during normal treatment or self-examination, only the pressure data collected by the inlet pressure sensor 18 can be used for judgment, or the pressure data collected by the inlet pressure sensor 18 and the outlet pressure sensor 19 can be used simultaneously for mutual corroboration. Of course, in some other embodiments, only the inlet pressure sensor 18 can be provided on the upstream side of the extracorporeal blood purification system 15, or only the outlet pressure sensor 19 can be provided on the downstream side of the extracorporeal blood purification system 15. Of course, if only one pressure sensor is provided, it is preferable to provide the inlet pressure sensor 18 on the upstream side of the extracorporeal blood purification system 15, because when the dialysate filter is blocked, abnormal pressure changes at the inlet end will be detected earlier. In this embodiment, the inlet pressure sensor 18 is located between the inlet pump 11 and the balance chamber assembly 12, and the outlet pressure sensor 19 is located between the outlet pump 16 and the balance chamber assembly 12.

[0035] like Figure 3As shown, the main control unit in this embodiment is configured to perform the following steps to achieve real-time, dynamic monitoring of the clogging status of the dialysate filter.

[0036] Step 1: Periodic Data Acquisition. During the self-test phase and / or operation of the hemodialysis equipment, pressure data of the water balance system is continuously acquired by a pressure sensor at a set sampling interval t (in milliseconds) within each preset detection cycle T. Specifically, the duration of the detection cycle T must be configured to cover at least one complete working cycle of the balance chamber assembly 12. The balance chamber assembly 12 operates as follows: one chamber of one balance chamber 121 is filled with dialysate while simultaneously discharging dialysate waste from the other chamber to the dialysate waste discharge module 17. Simultaneously, one chamber of the other balance chamber 121 supplies dialysate to the downstream extracorporeal blood purification system 15 while simultaneously filling the other chamber with dialysate waste from the extracorporeal blood purification system 15. The filling and discharging directions of the two chambers alternate. A working cycle, as referred to in this invention, means the time it takes for any balance chamber 121 to complete dialysate filling or dialysate waste discharge, i.e., ... Figure 4 The duration of a complete pressure pulse fluctuation is shown. The sampling interval t can be 1~200 milliseconds, such as 2 milliseconds, 5 milliseconds, 10 milliseconds, 20 milliseconds, 30 milliseconds, 50 milliseconds, 100 milliseconds, etc.

[0037] Step 2: At the end of each detection cycle T, calculate the characteristic parameters used to characterize the pressure fluctuation amplitude within that detection cycle based on all the pressure data collected during that detection cycle T.

[0038] In this embodiment, the characteristic parameter is the pressure change rate. Specifically, the pressure change rate is calculated as follows:

[0039]

[0040] in: This represents the rate of change of pressure. The difference between the maximum and minimum pressure values ​​within the detection cycle; The duration of the detection cycle; and These are the maximum and minimum pressure values ​​within the testing period, respectively.

[0041] Step 3: Compare the feature parameters with the preset blockage determination threshold to determine whether the feature parameters meet the preset blockage conditions: if yes, increment the blockage count and proceed to Step 4; if no, clear the blockage count and proceed to Step 1.

[0042] Specifically, in this embodiment, the calculated Compared with the preset pressure change rate threshold Compare them. If the rate of change of pressure... Less than the preset pressure change rate threshold This indicates abnormal pressure fluctuations in the current detection cycle, and an additional blockage count is added; if the pressure change rate... Greater than or equal to the preset pressure change rate threshold If the pressure fluctuation is normal during the current detection cycle, the blockage count will be reset to zero.

[0043] Specifically, the pressure change rate threshold In this embodiment, the pressure is set to 5~8 kPa / s. Set to 6 kPa / s.

[0044] Step 4: Determine whether the cumulative value of the blockage count K has reached the preset continuous anti-shake count threshold N: If yes, then determine that the dialysate filter is blocked; if no, then repeat Step 1.

[0045] Specifically, if K ≥ N, then it is determined that the dialysate filter has indeed become clogged. At this point, an audible and visual alarm is triggered via the equipment display screen and buzzer, and the time and pressure data of the clog are recorded for medical staff to investigate.

[0046] If K < N, it is determined that the dialysate filter is not clogged, and data acquisition continues in the next detection cycle T.

[0047] Specifically, the continuous image stabilization count threshold N ranges from 3 to 5 times. In this embodiment, N is set to 4 times. This means that the condition must be met in 4 consecutive detection cycles (i.e., 4 consecutive times). Only after this process is completed will the system confirm the blockage, thus effectively avoiding false alarms caused by single measurement errors or instantaneous pressure disturbances.

[0048] Specifically, when the pressure change rate is a characteristic parameter, it is more sensitive to the rate of change of pressure fluctuations and can capture the trend of pressure signal stabilization more quickly. However, it should be noted that it requires a higher sampling frequency from the pressure sensor.

[0049] Of course, in this embodiment, the characteristic parameter may also include the pressure difference. Specifically, the pressure difference is calculated as follows:

[0050]

[0051] in: This is the pressure difference; This represents the maximum pressure value within the detection cycle. This is the average value of all pressure data within the detection period; The first sample collected within the detection cycle One pressure data point; This refers to the number of pressure data collected during the detection period.

[0052] Specifically, in step three, the pressure difference calculated for that cycle can also be... Pressure difference threshold Comparison. For example... Figure 4 As shown, when the dialysate filter is working normally, the pressure exhibits obvious periodic fluctuations, and the calculated pressure difference... Larger, usually meets At this point, it indicates that the pressure fluctuation is normal, thus resetting the blockage counter K to zero and continuing with the next detection cycle.

[0053] like Figure 5 As shown, when the dialysate filter becomes clogged, the fluid flow is impeded, the pressure fluctuation amplitude decreases significantly, and the pressure curve tends to flatten. The calculated pressure difference at this time... It will become smaller, satisfying This indicates abnormal pressure fluctuations in the current detection cycle, suggesting possible filter blockage. Therefore, a blockage count increment operation is performed: K = K+1.

[0054] Specifically, pressure difference threshold The pressure is set to 3~6 kPa. In this embodiment, The pressure was set to 5 kPa based on the equipment calibration results.

[0055] Specifically, in step four, the continuous image stabilization count threshold N ranges from 3 to 5 times. In this embodiment, N is set to 4 times. This means that the condition must be met in 4 consecutive detection cycles (i.e., 4 consecutive times). Only after this process is completed will the system confirm the blockage, thus effectively avoiding false alarms caused by single measurement errors or instantaneous pressure disturbances.

[0056] In particular, the dialysate filter monitoring system of this embodiment has unique advantages during the equipment's self-test phase upon startup. Please refer to... Figure 1 and Figure 3When a blockage is detected during the self-test phase based on the above steps, a further blockage detection process can be performed to pinpoint the specific filter causing the blockage. The method is as follows: Close the first solenoid valve 132, the third solenoid valve 151, and the fourth solenoid valve 152, while simultaneously opening the second solenoid valve 142. At this point, the fluid path changes: the dialysate from the primary filter 13 no longer passes through the membrane of the secondary filter 14, but instead flows directly to the outlet pump 16 via the second branch 141. In this state, the fluid only needs to flow through the primary filter 13, bypassing the secondary filter 14 and the extracorporeal blood purification system 15. Then, the main control unit executes steps one through four again to achieve real-time, dynamic monitoring of the dialysate filter blockage status.

[0057] If the result is still "blockage" at this time, it indicates that the blockage source is located in the primary filter 13.

[0058] If the result is normal (no blockage) at this time, it indicates that the blockage source is located in the secondary filter 14.

[0059] Through this simple switching process, the system can accurately locate the faulty filter and guide operators to replace it efficiently. It should be noted that the above fluid path switching diagnostic is only performed during the device's power-on self-test phase. During the self-test phase, since the device is not connected to a patient, the above test is feasible. However, during normal treatment, if blockage occurs, to ensure patient safety, the device will directly implement preset protective measures (such as reducing the ultrafiltration rate, issuing a high-level alarm, etc.) and will not perform this fluid path switching diagnostic to avoid interfering with the ongoing treatment.

[0060] Furthermore, even if a brief switch in the fluid circuit is necessary during treatment due to special circumstances, it is feasible to maintain a low blood flow rate to prevent clotting, as anticoagulants are routinely used in hemodialysis. Therefore, even if a switch causes a temporary interruption of dialysate or replacement fluid supply for several seconds to tens of seconds, it will not pose a risk of clotting to the patient's blood. Treatment can be resumed after the fault is resolved, and those skilled in the art will understand that such brief, controlled fluid circuit operations are clinically safe. If the fault cannot be resolved by pausing, the patient must be weaned off the machine.

[0061] In summary, this invention cleverly utilizes the inherent pressure fluctuation characteristics of the dialysis equipment's water balance system to achieve low-cost, high-precision, and interference-resistant real-time monitoring of the dialysate filter's clogging status. This system operates throughout the entire process of equipment self-checking and treatment, significantly improving the safety and reliability of hemodialysis treatment.

[0062] In this article, "and / or" represents two logical relationships: "and" and "or". For example, "A and / or B" means "A and B" and "A or B".

[0063] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A dialysate filter monitoring system for a hemodialysis device, applied to the water balance system of a hemodialysis device, the water balance system comprising an inlet pump, a balance chamber assembly, a dialysate filter, and an outlet pump, wherein the inlet pump, the dialysate channel of the balance chamber assembly, and the dialysate filter are sequentially connected for supplying dialysis fluid to an extracorporeal blood purification system, and the outlet pump is used to discharge dialysis waste fluid flowing from the extracorporeal blood purification system through the dialysis waste fluid channel of the balance chamber assembly; a raw fluid branch is provided between the dialysate filter and the downstream side of the extracorporeal blood purification system; characterized in that: The dialysate filter monitoring system includes: The pressure detection unit includes an inlet pressure sensor located upstream of the dialysate filter and / or an outlet pressure sensor located downstream of the dialysate filter. The main control unit, electrically connected to the pressure detection unit, is configured to perform the following steps: Step 1: During the self-test phase and / or operation of the hemodialysis equipment, pressure data of the water balance system is continuously collected by a pressure sensor at a set sampling interval within each preset detection cycle, using a preset detection cycle as the time unit; the pressure sensor is the inlet pressure sensor and / or the outlet pressure sensor. Step Two: At the end of each detection cycle, based on all pressure data collected during that cycle, using the same inlet or outlet pressure sensor, calculate a characteristic parameter characterizing the pressure fluctuation amplitude during that cycle. This characteristic parameter includes the pressure change rate, which is calculated as follows: in: This represents the rate of change of pressure. The difference between the maximum and minimum pressure values ​​within the detection cycle; The duration of the detection cycle; and These are the maximum and minimum pressure values ​​within the testing period, respectively. Step 3: Compare the feature parameters with the preset blockage determination threshold to determine whether the feature parameters meet the preset blockage conditions: if yes, increment the blockage count and proceed to Step 4; if no, clear the blockage count and proceed to Step 1. Step 4: Determine whether the cumulative value of the blockage count has reached the preset continuous anti-shake count threshold: if yes, then determine that the dialysate filter is blocked; if no, then repeat Step 1.

2. The hemodialysis equipment dialysate filter monitoring system according to claim 1, characterized in that: In step three, if the pressure change rate Less than the preset pressure change rate threshold This indicates abnormal pressure fluctuations in the current detection cycle, and an additional blockage count is added; if the pressure change rate... Greater than or equal to the preset pressure change rate threshold If the pressure fluctuation is normal during the current detection cycle, the blockage count will be reset to zero.

3. The hemodialysis equipment dialysate filter monitoring system according to claim 2, characterized in that: The inlet pressure sensor is disposed between the inlet pump and the balance chamber assembly. When the inlet pressure sensor is used to monitor the pressure change rate, the pressure change rate threshold is... Set to 5~8 kPa / s.

4. The hemodialysis equipment dialysate filter monitoring system according to any one of claims 1-3, characterized in that: The characteristic parameters are calculated using pressure data acquired by the same inlet pressure sensor or outlet pressure sensor and include a pressure difference value. The pressure difference is calculated as follows: in: This is the pressure difference; This represents the maximum pressure value within the detection cycle. This is the average value of all pressure data within the detection period; The first sample collected within the detection cycle One pressure data point; This refers to the number of pressure data collected during the detection period.

5. The hemodialysis equipment dialysate filter monitoring system according to claim 4, characterized in that: In step three, if the pressure difference is less than the preset pressure difference threshold If the pressure fluctuation in the current detection cycle is abnormal, an additional blockage count will be added; if the pressure difference is... Greater than or equal to the preset pressure difference threshold If the pressure fluctuation is normal during the current detection cycle, the blockage count will be reset to zero.

6. The hemodialysis equipment dialysate filter monitoring system according to claim 5, characterized in that: The inlet pressure sensor is disposed between the inlet pump and the balance chamber assembly. When the inlet pressure sensor is used to monitor the pressure difference, the pressure difference threshold is... Set to 3~6 kPa.

7. The hemodialysis equipment dialysate filter monitoring system according to claim 1, characterized in that: The duration of the detection cycle is configured to cover at least one full working cycle of the balance cavity assembly; And / or, The range of the continuous stabilization count threshold is 3 to 5 times.

8. The hemodialysis equipment dialysate filter monitoring system according to any one of claims 1-3, 7, characterized in that: When the dialysate filter is determined to be clogged, an audible and visual alarm is triggered, and the time and pressure data of the clogging are recorded. And / or, If the dialysate filter is determined to be clogged during the operation of the hemodialysis equipment, treatment protection measures are implemented.

9. The hemodialysis equipment dialysate filter monitoring system according to any one of claims 1-3, 7, characterized in that: The dialysate filter includes a primary filter and a secondary filter connected in series and located upstream of the extracorporeal blood purification system. The primary filter is located upstream of the secondary filter. The inlet chambers of the primary filter and the secondary filter are respectively provided with a first branch and a second branch between themselves and the downstream side of the extracorporeal blood purification system. A first solenoid valve and a second solenoid valve are respectively provided on the first branch and the second branch. A third solenoid valve and a fourth solenoid valve are respectively provided at the inlet and outlet ends of the extracorporeal blood purification system. During the self-test phase of the hemodialysis equipment, if the dialysate filter is found to be clogged, a filter clogging judgment is also performed. The method is as follows: close the first, third, and fourth solenoid valves, open the second solenoid valve, and execute steps one to four. If the judgment result is that the filter is clogged, then the primary filter is clogged; otherwise, the secondary filter is clogged.

10. The hemodialysis equipment dialysate filter monitoring system according to any one of claims 1-3, 7, characterized in that: It also includes an alarm unit, which is used to trigger an audible and visual alarm when the dialysate filter is determined to be clogged, and to record the time and pressure data of the clog occurrence through the main control unit.

Images