Three-cavity hemodiafiltration device and hemodiafiltration method thereof

Abstract

The invention discloses a three-cavity hemodiafiltration device and a hemodiafiltration method thereof, relates to the technical field of medical instruments, and aims to solve the problem that an existing double-cavity hemodiafiltration device cannot flexibly switch a replacement mode, the three-cavity hemodiafiltration device comprises a hemodiafiltration device body, the dialysis filter body comprises a first cavity, a second cavity and a third cavity which are sequentially and coaxially arranged in the blood flowing direction and communicate with one another, the interiors of the first cavity, the second cavity and the third cavity are all connected with corresponding hollow fiber membrane bundles in a sealed mode, and the two ends of the side faces of the first cavity and the third cavity are each provided with a connector. A dialysate inlet and a dialysate outlet are formed in the two ends of the side face of the second cavity respectively, so that the filter can flexibly meet the switching requirements of a front replacement mode, a rear replacement mode and a mixed replacement mode, replacement liquid is filtered again, the purity of the replacement liquid is improved, and the method further has the function of improving the dialysis effect.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more specifically, to a three-chamber hemodialysis filter and a hemodialysis filtration method thereof. Background Technology

[0002] Hemodiafiltration (HDF) is an important treatment widely used for diseases such as chronic renal failure, acute renal failure, and drug poisoning. It combines the advantages of hemodialysis (HD) and hemofiltration (HF), removing medium-to-large molecular weight toxins and excess water from the blood through diffusion and convection, thereby reducing related complications and improving patients' quality of life and prognosis.

[0003] During HDF treatment, three replacement modes are typically available: pre-replacement, post-replacement, and hybrid replacement. However, the internal structure of existing dual-lumen hemofilters is relatively fixed, usually only allowing for pre-replacement or post-replacement modes. This structural limitation makes it difficult for the filter to simultaneously support mixed pre-replacement and post-replacement operations, failing to meet the precise control requirements of the replacement fluid in hybrid replacement modes.

[0004] Therefore, how to solve the problem that existing dual-chamber blood filters cannot flexibly switch replacement modes is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a three-chamber hemodialysis filter that can flexibly adapt to the switching requirements of pre-replacement mode, post-replacement mode and mixed replacement mode, realize the re-filtration of replacement fluid, improve the purity of replacement fluid and improve dialysis effect.

[0006] Another objective of this invention is to provide a hemodialysis filtration method including the above-mentioned three-chamber hemodialysis filter, which satisfies the diverse treatment needs of different patients, improves the efficiency of toxin removal, the utilization efficiency of dialysate and replacement fluid, and ensures the safety of dialysis treatment.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A three-chamber hemodialysis filter includes: a dialysis filter body, the dialysis filter body including a first chamber, a second chamber and a third chamber arranged coaxially and connected in sequence along the blood flow direction, the first chamber, the second chamber and the third chamber are all sealed with corresponding hollow fiber membrane bundles, the first chamber and the third chamber are provided with connectors at both ends of their sides, and the second chamber is provided with a dialysate inlet and a dialysate outlet at both ends of its side.

[0009] Preferably, there are multiple joints, which are evenly distributed around the first and third chambers.

[0010] Preferably, the connector includes a first connector and a second connector located on the side of the first chamber, and a first end cap is provided at one end of the first chamber, with a blood inlet on the first end cap.

[0011] Preferably, the connector further includes a third connector and a fourth connector located on the side of the third chamber, and a second end cap is provided at one end of the third chamber, with a blood outlet on the second end cap.

[0012] Preferably, the first chamber, the second chamber, and the third chamber are all cylindrical structures, and the second chamber is connected to the first chamber and the third chamber through a connector.

[0013] Preferably, the first end cap and the second end cap are connected by threads or ultrasonic welding to the corresponding first chamber and third chamber.

[0014] Preferably, when the first end cap and the second end cap are connected to the corresponding first chamber and third chamber by threads, a sealing ring is provided between the first end cap and the first chamber, and a sealing ring is also provided between the second end cap and the third chamber.

[0015] Preferably, the ends of the hollow fiber membrane bundle are sealed and bonded to the first chamber, the second chamber, and the third chamber with polyurethane adhesive.

[0016] Preferably, the hollow fiber membrane bundles in the first and third chambers are one or more of polysulfone, polyethersulfone, or polyester polymer composite membranes, and the hollow fiber membrane bundles in the second chamber are one or more of polysulfone, polyethersulfone, polyester polymer composite membranes, or cellulose triacetate membranes.

[0017] A hemodialysis filtration method using a three-chamber hemodialysis filter, applied to any of the three-chamber hemodialysis filters described above, the hemodialysis filtration method comprising:

[0018] The appropriate replacement mode is switched according to the treatment needs. Replacement modes include anterior replacement mode, posterior replacement mode, and hybrid replacement mode.

[0019] When switching to pre-displacement mode, replacement fluid is introduced into the first chamber, and dialysate is introduced into the second and third chambers. The replacement fluid first enters the first chamber for filtration and dilutes the blood flowing through the first chamber. The diluted blood then passes through the second and third chambers in sequence. The dialysate in the second and third chambers performs dialysis on the diluted blood. The dialyzed blood then flows out from the third chamber.

[0020] When switching to post-displacement mode, dialysate is introduced into the first and second chambers respectively, and replacement fluid is introduced into the third chamber. Blood passes through the first and second chambers in sequence. The dialysate in the first and second chambers performs dialysis on the blood. The dialyzed blood enters the third chamber. The replacement fluid in the third chamber, after being filtered, dilutes the dialyzed blood flowing through the third chamber. The diluted blood then flows out of the third chamber.

[0021] When switching to the mixed replacement mode, replacement fluid is introduced into the first and third chambers, and dialysate is introduced into the second chamber. The replacement fluid enters the first and third chambers for filtration. The replacement fluid in the first chamber dilutes the blood flowing through it. The diluted blood then enters the second chamber, where the dialysate performs dialysis. The dialyzed blood then enters the third chamber, where the filtered replacement fluid further dilutes the dialyzed blood. The diluted blood then flows out of the third chamber.

[0022] The three-chamber hemodialysis filter provided by this invention includes a dialysis filter body, which comprises a first chamber, a second chamber, and a third chamber arranged coaxially and connected along the blood flow direction. This allows blood to pass through multiple chambers with different functions during dialysis. The three-chamber design can more fully utilize the diffusion and convection effects of the hollow fiber membrane bundles, thereby significantly improving the toxin removal rate in the blood, especially for medium and large molecular toxins, providing patients with more effective treatment. The first, second, and third chambers are all sealed with corresponding hollow fiber membrane bundles. This sealed connection ensures that the blood can only exchange substances with the dialysate or replacement fluid through the hollow fiber membrane bundles in each chamber, ensuring the precision of the dialysis and filtration process, avoiding non-selective loss of blood components, and preventing external contaminants from entering the blood. This ensures the safety and effectiveness of the dialysis process and reduces the occurrence of complications such as infection.

[0023] The first and third chambers each have connectors at both ends of their sides, while the second chamber has dialysate inlets and outlets at both ends of its side. This allows the filter to adapt to pre-replacement, post-replacement, and mixed replacement modes. In pre-replacement mode, the replacement fluid enters through the connector in the first chamber, pre-diluting the blood and reducing the risk of clotting. In post-replacement mode, the replacement fluid enters through the connector in the third chamber, diluting the concentrated blood and improving toxin removal efficiency. In mixed replacement mode, the replacement fluid enters through connectors in both the first and third chambers, combining the advantages of both pre-replacement and post-replacement, thus improving treatment flexibility and effectiveness and meeting the personalized needs of different patients. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of the three-chamber hemodialysis filter provided by the present invention;

[0026] Figure 2 This is a cross-sectional view of the three-chamber hemodialysis filter provided by the present invention;

[0027] Figure 3 This is a schematic diagram of the connector of the three-chamber hemodialysis filter provided by the present invention;

[0028] Figure 4 This diagram illustrates the steps of a hemodialysis filtration method using the three-chamber hemodialysis filter provided by the present invention.

[0029] Figure label:

[0030] 1-First chamber; 2-Second chamber; 3-Third chamber; 4-Hollow fiber membrane bundle; 5-Dialysis fluid inlet; 6-Dialysis fluid outlet; 7-First connector; 8-Second connector; 9-First end cap; 10-Third connector; 11-Fourth connector; 12-Second end cap; 13-Connector. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] It should be noted that the directional terms such as "up" and "down" in the following text are defined based on the accompanying drawings in the instruction manual.

[0034] The core of this invention is to provide a three-chamber hemodialysis filter that can flexibly adapt to the switching requirements of pre-replacement, post-replacement, and mixed replacement modes, achieving re-filtration of the replacement fluid, improving the purity of the replacement fluid, and simultaneously enhancing dialysis efficacy. Another core aspect of this invention is to provide a hemodialysis filtration method incorporating the aforementioned three-chamber hemodialysis filter, thereby meeting the diverse treatment needs of different patients, improving toxin removal efficiency, dialysate and replacement fluid utilization efficiency, and ensuring the safety of dialysis treatment.

[0035] Please refer to Figure 1 and Figure 2 A three-chamber hemodialysis filter includes a dialysis filter body.

[0036] Specifically, the dialysis filter body includes a first chamber 1, a second chamber 2, and a third chamber 3 arranged coaxially and connected along the blood flow direction. This allows blood to pass through multiple chambers with different functions during dialysis. The three-chamber design can more fully utilize the diffusion and convection effects of the hollow fiber membrane bundles 4, thereby significantly improving the removal rate of toxins in the blood, especially for medium and large molecular toxins, providing patients with more effective treatment. The first chamber 1, the second chamber 2, and the third chamber 3 are all sealed with corresponding hollow fiber membrane bundles 4. By sealing the hollow fiber membrane bundles 4, it is ensured that the blood can only exchange substances with the dialysate or replacement fluid through the hollow fiber membrane bundles 4 in each chamber. This ensures the precision of the dialysis and filtration process, avoids non-selective loss of blood components, and prevents external contaminants from entering the blood, ensuring the safety and effectiveness of the dialysis process and reducing the occurrence of complications such as infection.

[0037] The first chamber 1 and the third chamber 3 are equipped with connectors at both ends of their sides, and the second chamber 2 is equipped with a dialysate inlet 5 and a dialysate outlet 6 at both ends of its side. This allows the filter to adapt to pre-replacement, post-replacement, and mixed replacement modes. In pre-replacement mode, the replacement fluid enters through the connector in the first chamber 1 to dilute the blood in advance and reduce the risk of coagulation. In post-replacement mode, the replacement fluid enters through the connector in the third chamber 3 to dilute the concentrated blood and improve the efficiency of toxin removal. In mixed replacement mode, the replacement fluid enters through the connectors in both the first chamber 1 and the third chamber 3, combining the advantages of pre-replacement and post-replacement, improving the flexibility and effectiveness of treatment, and meeting the personalized needs of different patients.

[0038] The dialysate inlet 5 is located on the lower side of the second chamber 2, serving as the channel for pure dialysate to enter the second chamber 2. As the dialysate flows in through the inlet 5, it comes into contact with the hollow fiber membrane bundle 4 within the second chamber 2, undergoing efficient convection exchange through the membrane's micropores to remove small and medium-sized toxins from the blood. Simultaneously, the dialysate outlet 6 is located on the upper side of the second chamber 2, serving as the channel for dialysis waste fluid discharge. After convection exchange, the dialysis waste fluid carrying toxins and excess water is discharged through the outlet 6, ensuring the continuity and effectiveness of the dialysis process. This design not only optimizes the flow path of the dialysate but also improves dialysis efficiency, ensuring the safety and effectiveness of the treatment.

[0039] The three-chamber hemodialysis filter designed in the above manner filters the replacement fluid through the chambers at both ends of the filter, achieving secondary filtration of the replacement fluid. This significantly improves the purity of the replacement fluid, effectively reduces the content of endotoxins and other toxic substances, and decreases the incidence of hemodialysis complications. At the same time, it can meet the clinical requirements for multiple treatment modes of HDF technology, namely pre-replacement mode, post-replacement mode, and mixed replacement mode, and also improves the dialysis effect.

[0040] In the above embodiments, multiple connectors are provided, and the multiple connectors are evenly distributed around the first chamber 1 and the third chamber 3.

[0041] It should be noted that the multiple connectors evenly distributed around the first chamber 1 and the third chamber 3 ensure a more uniform distribution of the replacement fluid upon entering the chambers, preventing the fluid from concentrating in one area. This improves the uniformity of the mixing between the replacement fluid and blood, enhances the dilution effect of the replacement fluid, and improves the treatment outcome. The even distribution of multiple connectors also reduces pressure differences when the replacement fluid enters the chambers, helping to maintain pressure balance within the chambers and preventing damage to the hollow fiber membrane bundles 4 or a decrease in filtration efficiency due to uneven pressure, thus improving the stability and reliability of dialysis. This design allows for pre-dilution of the blood in pre-replacement mode, reducing the risk of coagulation; in post-replacement mode, it better dilutes concentrated blood, improving toxin removal efficiency; and in mixed replacement mode, it combines the advantages of both pre- and post-replacement methods, further optimizing the treatment effect.

[0042] Preferably, the connector includes a first connector 7 and a second connector 8 located on the side of the first chamber 1. One end of the first chamber 1 is provided with a first end cap 9, and the first end cap 9 is provided with a blood inlet. The first connector 7 is located on the upper side of the first chamber 1 (that is, the side of the first chamber 1 closest to the first end cap 9), and the second connector 8 is located on the lower side of the first chamber 1 (that is, the side of the first chamber 1 furthest from the first end cap 9).

[0043] Specifically, the uppermost end of the dialysis filter body is provided with a first end cap 9, which is specifically designed to connect to the arterial segment of the extracorporeal circulation circuit. The patient's blood flows into the first end cap 9 through the blood inlet on the first end cap 9 via the arterial segment of the extracorporeal circulation circuit, and then smoothly enters the interior of the dialysis filter body. The lower end of the first end cap 9 is tightly connected to the first chamber 1. The first chamber 1 not only provides a stable filling space for the hollow fiber membrane bundle 4, but also creates the necessary channel for the flow of replacement fluid. A first connector 7 and a second connector 8 are designed at both ends of the side of the first chamber 1, respectively, to maximize the flow of the filtered replacement fluid. The replacement fluid is mixed with blood to reduce the risk of clotting. The main function of the first connector 7 and the second connector 8 is to connect to the replacement fluid catheter. The replacement fluid, which has been initially filtered by two microparticle filters in the dialysis device, enters the first chamber 1 precisely through the first connector 7 and / or the second connector 8. After entering the first chamber 1, the replacement fluid will be finely filtered again by the hollow fiber membrane bundle 4 in the first chamber 1, effectively intercepting harmful substances such as endotoxins in the replacement fluid. After this key filtration step, the replacement fluid becomes purer and then enters the interior of the hollow fiber membrane bundle 4, where it is fully mixed with the blood in the membrane to ensure the safety and effectiveness of the treatment.

[0044] Understandably, one end of the first chamber 1 is provided with a first end cap 9, and the first end cap 9 has a blood inlet. The patient's blood enters the first end cap 9 through the blood inlet, and then enters the first chamber 1 to mix thoroughly with the replacement fluid. By providing a first connector 7 and a second connector 8 on the first chamber 1, the first chamber 1 can be used as a replacement fluid filter in the pre-replacement mode and the mixed replacement mode, and as a dialyzer in the post-replacement mode.

[0045] Furthermore, the connector also includes a third connector 10 and a fourth connector 11 located on the side of the third chamber 3. One end of the third chamber 3 is provided with a second end cap 12, which has a blood outlet. The third connector 10 is located on the upper side of the third chamber 3 (that is, the side of the third chamber 3 away from the second end cap 12), and the fourth connector 11 is located on the lower side of the third chamber 3 (that is, the side of the third chamber 3 close to the second end cap 12).

[0046] Specifically, the third chamber 3 has a third connector 10 and a fourth connector 11 at its two ends on the sides, which maximizes the mixing of the filtered replacement fluid and blood, improving the efficiency of toxin removal. The main function of the third connector 10 and the fourth connector 11 is to connect to the replacement fluid catheter. The replacement fluid, which has been initially filtered by two microparticle filters in the dialysis device, enters the third chamber 3 precisely through the third connector 10 and / or the fourth connector 11. After entering the third chamber 3, the replacement fluid is further filtered by the hollow fiber membrane bundle 4 in the third chamber 3, effectively intercepting endotoxins and other harmful substances in the replacement fluid. After this key filtration step, the replacement fluid becomes purer and then enters the interior of the hollow fiber membrane bundle 4, where it mixes thoroughly with the blood inside the membrane, ensuring the safety and effectiveness of the treatment. The lower end of the third chamber 3 is fixedly installed with the second end cap 12, which is used to connect to the external circulation venous segment of the body 13. The purified blood flows out through the second end cap 12 and is then reinfused into the patient.

[0047] It should be noted that one end of the third chamber 3 is equipped with a second end cap 12, which has a blood outlet, allowing purified blood to flow out of the third chamber 3 and be returned to the patient through the blood outlet on the second end cap 12. By providing a third connector 10 and a fourth connector 11 on the third chamber 3, it can be used as a replacement fluid filter in post-replacement and mixed replacement modes, and as a dialyzer in pre-replacement mode.

[0048] In one feasible implementation, please refer to Figure 1 and Figure 2A first connector 7 is located at the upper side of the first chamber 1, and a second connector 8 is located at the lower side. A third connector 10 is located at the upper side of the third chamber 3, and a fourth connector 11 is located at the lower side. A dialysate outlet 6 is located at the upper side of the second chamber 2, and a dialysate inlet 5 is located at the lower side. In this configuration, during pre-displacement therapy, the second connector 8 is closed, and the dialysate inlet 5, fourth connector 11, dialysate outlet 6, and third connector 10 are connected to the dialysate inlet and outlet lines on the dialysis machine, respectively. The replacement fluid enters the first chamber 1 through the first connector 7 and is further intercepted by the hollow fiber membrane bundle 4 in the first chamber 1 before entering the blood inside the hollow fiber membrane bundle 4. The blood filtered by the hollow fiber membrane bundle 4 in the second chamber 2 enters the hollow fiber membrane bundle 4 in the third chamber 3. The purified dialysate carries away the toxins in the blood and removes them from the body through the second chamber 2 and the third chamber 3. During pre-replacement HDF treatment, the third chamber 3 below the three-chamber hemodialysis filter is used as the dialyzer, increasing the efficiency of toxin removal, while the first chamber 1 above is used as the replacement fluid filter to ensure the purity of the replacement fluid. During post-replacement treatment, the fourth connector 11 is closed, and the dialysate inlet 5, second connector 8, dialysate outlet 6, and first connector 7 are connected to the dialysate inlet and outlet lines on the dialysis machine, respectively. Pure dialysate carries away toxins from the blood through the first chamber 1 and the second chamber 2. Blood filtered by the hollow fiber membrane bundles 4 in the first chamber 1 and the second chamber 2 enters the hollow fiber membrane bundle 4 in the third chamber 3. The replacement fluid enters the third chamber 3 through the third connector 10 and is further intercepted by the hollow fiber membrane bundle 4 in the third chamber 3, mixing with the blood inside the hollow fiber membrane bundle 4 to dilute the concentrated blood. In post-replacement HDF treatment, the upper chamber 1 of the three-chamber hemodialysis filter functions as the dialyzer, increasing the efficiency of toxin removal, while the lower chamber 3 functions as the replacement fluid filter, ensuring the purity of the replacement fluid. In mixed replacement therapy mode, the second connector 8 and the fourth connector 11 are closed. The replacement fluid enters the first chamber 1 and the third chamber 3 through the first connector 7 and the third connector 10, respectively. It is further filtered by the hollow fiber membrane bundles 4 in the first chamber 1 and the third chamber 3, respectively, to remove endotoxins before entering the blood within the hollow fiber membrane bundles 4 in the first chamber 1 and the third chamber 3. In other words, during mixed replacement HDF treatment, both the first chamber 1 and the third chamber 3 of the three-chamber hemodialysis filter function as replacement fluid filters, achieving secondary filtration of the replacement fluid and significantly improving its purity. This effectively enhances toxin removal efficiency without increasing the risk of coagulation, providing patients with a more efficient and safer treatment method.

[0049] It should be noted that when performing the pre-replacement treatment mode, the replacement fluid can also enter the first chamber 1 simultaneously through the first connector 7 and the second connector 8; when performing the post-replacement treatment mode, the replacement fluid can also enter the third chamber 3 simultaneously through the third connector 10 and the fourth connector 11; when performing the mixed replacement treatment mode, the replacement fluid can enter the corresponding chamber simultaneously through the first connector 7, the second connector 8, the third connector 10 and the fourth connector 11.

[0050] Please refer to Figure 1 , Figure 2 and Figure 3 The first chamber 1, the second chamber 2 and the third chamber 3 are all cylindrical structures, and the second chamber 2 is connected to the first chamber 1 and the third chamber 3 through the connector 13.

[0051] It is understandable that a connecting body 13 is provided between the first chamber 1 and the second chamber 2. The upper end of the connecting body 13 connects to the lower end of the first chamber 1, and the lower end of the connecting body 13 connects to the upper end of the second chamber 2. The connecting body 13 is a hollow cylindrical structure, which not only provides a stable connection between the first chamber 1 and the second chamber 2, but also provides the necessary space for the flow of mixed blood. Through this design, blood can flow smoothly between the chambers, ensuring the continuity and efficiency of the entire dialysis process. A connecting body 13 is also provided between the second chamber 2 and the third chamber 3. The upper end of the connecting body 13 connects to the lower end of the second chamber 2, and the lower end of the connecting body 13 connects to the upper end of the third chamber 3. The connecting body 13 also adopts a hollow cylindrical structure, which not only provides a stable connection between the second chamber 2 and the third chamber 3, but also provides the necessary space for the flow of mixed blood. This design not only ensures the smooth flow of blood between the chambers, but also reduces pressure loss during blood flow through a reasonable structural layout, thereby improving the efficiency of the entire dialysis process. The first chamber 1, the second chamber 2, and the third chamber 3 provide loading space for the hollow fiber membrane bundle 4. The first chamber 1 and the third chamber 3 provide flow space for the replacement fluid or dialysate, while the second chamber 2 provides flow space for the dialysate. The design of the first chamber 1 and the third chamber 3 ensures that the replacement fluid can be effectively filtered again, further improving its purity. The design of the second chamber 2 ensures that the dialysate can effectively exchange with toxins in the blood via convection, achieving a toxin removal effect.

[0052] It should be noted that the first chamber 1, the second chamber 2, and the third chamber 3 all adopt a cylindrical structure, making the entire dialysis filter more compact and maximizing space utilization. The cylindrical structure not only facilitates manufacturing and assembly but also ensures smoother liquid flow within the chambers, reducing dead zones and eddies, and improving filtration efficiency. The cylindrical structure also contributes to the uniform distribution of replacement fluid and dialysate within the chambers, reducing pressure loss during fluid entry and exit, ensuring uniform and stable fluid flow, and improving the utilization efficiency of both dialysate and replacement fluid.

[0053] In the above case, the first end cap 9 and the second end cap 12 are connected by thread or ultrasonic welding to the corresponding first chamber 1 and third chamber 3.

[0054] It should be noted that the first end cap 9 and the second end cap 12 are connected to the corresponding first chamber 1 and third chamber 3 via threaded connections. This connection method provides high-strength mechanical fixation, ensuring that the connections between components will not loosen even under high pressure or high flow conditions during dialysis, thus enhancing the stability and reliability of the equipment. The threaded connection, through its tight thread fit, effectively prevents liquid leakage, ensuring the sealing of dialysate and blood within the chambers. Ultrasonic welding is a highly efficient connection method that uses the heat generated by high-frequency vibration to weld materials together, forming a strong connection. This welding method not only offers high connection strength but also high welding speed, improving production efficiency while reducing the risk of loosening and leakage that may occur with mechanical connections. Ultrasonic welding can create seamless connections, further improving sealing performance. The heat generated during welding melts and fuses the materials together, forming a continuous sealing surface that effectively prevents liquid leakage, improving the safety and reliability of the equipment.

[0055] In practical applications, there are no restrictions on the connection method between the end cap and the chamber.

[0056] In the above embodiments, when the first end cover 9 and the second end cover 12 are connected to the corresponding first chamber 1 and third chamber 3 by threads, a sealing ring is provided between the first end cover 9 and the first chamber 1, and a sealing ring is also provided between the second end cover 12 and the third chamber 3.

[0057] It is understandable that sealing rings are provided between the first end cap 9 and the first chamber 1, and between the second end cap 12 and the third chamber 3, which can effectively prevent liquid leakage at the connection, ensure the sealing of dialysate and blood in the chamber, and improve the safety and reliability of dialysis.

[0058] In a preferred embodiment, the ends of the hollow fiber membrane bundle 4 are sealed and bonded to the first chamber 1, the second chamber 2 and the third chamber 3 with polyurethane adhesive.

[0059] It should be noted that the ends of the hollow fiber membrane bundle 4 are sealed and bonded to the first chamber 1, the second chamber 2, and the third chamber 3 with polyurethane adhesive. This bonding method provides extremely high sealing performance. The polyurethane adhesive has excellent adhesion and sealing properties, effectively preventing leakage of blood and dialysate at the connection between the hollow fiber membrane bundle 4 and the chambers, ensuring the sealing of the entire dialysis process. The polyurethane adhesive also has good durability and anti-aging properties, ensuring the stability and reliability of the hollow fiber membrane bundle 4 during long-term use.

[0060] In the above case, the hollow fiber membrane bundles 4 in the first chamber 1 and the third chamber 3 are one or more of polysulfone, polyethersulfone, or polyester polymer composite membranes, and the hollow fiber membrane bundles 4 in the second chamber 2 are one or more of polysulfone, polyethersulfone, polyester polymer composite membranes, or cellulose triacetate membranes.

[0061] Specifically, the hollow fiber membrane bundle 4 in the first chamber 1 is made of one or more of polysulfone, polyethersulfone, or polyester polymer composite membrane. Polyurethane adhesive is provided above and below the first chamber 1. The polyurethane adhesive is used to fix the upper and lower ends of the hollow fiber membrane bundle 4 in the first chamber 1. During the assembly process, the polyurethane adhesive is cut by a precision cutting knife to open the upper inlet and lower outlet of the hollow fiber membrane bundle 4 in the first chamber 1, and at the same time obtain a smooth, mirror-like end face. The hollow fiber membrane bundle 4 in the second chamber 2 is made of one or more of the following materials: polysulfone, polyethersulfone, polyester polymer composite membrane, or cellulose triacetate membrane. Small molecules such as urea and creatinine and medium molecules such as β2-microglobulin in the blood are discharged from the body through the micropores on the hollow fiber membrane bundle 4 in the second chamber 2. Alkaline ions in the dialysate enter the blood to correct the body's acid-base balance. Polyurethane adhesive is provided at the top and bottom of the second chamber 2. The polyurethane adhesive is used to fix the upper and lower ends of the hollow fiber membrane bundle 4 in the second chamber 2. During the assembly process, the polyurethane adhesive is cut with a precision cutting knife to open the upper inlet and lower outlet of the second hollow fiber membrane bundle 4, and at the same time obtain a smooth, mirror-like end face. The hollow fiber membrane bundle 4 in the third chamber 3 is made of one or more of polysulfone, polyethersulfone, or polyester polymer composite membrane. The upper and lower parts of the hollow fiber membrane bundle 4 in the third chamber 3 are fixed with polyurethane adhesive. During the assembly process, the polyurethane adhesive is cut by a precision cutting knife, and the upper inlet and lower outlet of the hollow fiber membrane bundle 4 in the third chamber 3 are opened, thus obtaining a smooth, mirror-like end face.

[0062] It should be noted that the hollow fiber membrane bundles 4 in the first chamber 1 and the third chamber 3 are made of one or more of polysulfone, polyethersulfone, or polyester polymer composite membranes. These materials have excellent filtration performance, effectively intercepting endotoxins and other harmful substances in the replacement fluid, ensuring the high purity of the replacement fluid, and can also remove small and medium molecular weight toxins from the blood, improving the dialysis effect. The hollow fiber membrane bundle 4 in the second chamber 2 is made of one or more of polysulfone, polyethersulfone, polyester polymer composite membranes, or cellulose triacetate membranes. These materials not only have highly efficient filtration performance, but also effectively remove small and medium molecular weight toxins from the blood, improving the dialysis effect.

[0063] Please refer to Figure 4 A hemodialysis filtration method using a three-chamber hemodialysis filter, applied to the aforementioned three-chamber hemodialysis filter, the hemodialysis filtration method comprising:

[0064] Step S1: Switch to the corresponding replacement mode according to the treatment needs. Replacement modes include anterior replacement mode, posterior replacement mode, and hybrid replacement mode.

[0065] Step S2: When switching to the pre-displacement mode, replacement fluid is introduced into the first chamber 1, and dialysate is introduced into the second chamber 2 and the third chamber 3. The replacement fluid first enters the first chamber 1 for filtration and dilutes the blood flowing through the first chamber 1. The diluted blood then passes through the second chamber 2 and the third chamber 3 in sequence. The dialysate in the second chamber 2 and the third chamber 3 performs dialysis on the diluted blood. The dialyzed blood then flows out from the third chamber 3.

[0066] Step S3: When switching to post-displacement mode, dialysate is introduced into the first chamber 1 and the second chamber 2 respectively, and replacement fluid is introduced into the third chamber 3. Blood passes through the first chamber 1 and the second chamber 2 in sequence. The dialysate in the first chamber 1 and the second chamber 2 performs dialysis on the blood. The dialyzed blood enters the third chamber 3. The replacement fluid in the third chamber 3, after filtration, dilutes the dialyzed blood flowing through the third chamber 3. The diluted blood flows out from the third chamber 3.

[0067] Step S4: When switching to the mixed replacement mode, replacement fluid is introduced into the first chamber 1 and the third chamber 3 respectively, and dialysate is introduced into the second chamber 2. The replacement fluid enters the first chamber 1 and the third chamber 3 respectively for filtration. The replacement fluid in the first chamber 1 dilutes the blood flowing through the first chamber 1. The diluted blood enters the second chamber 2. The dialysate in the second chamber 2 performs dialysis on the diluted blood. The dialyzed blood enters the third chamber 3. The replacement fluid in the third chamber 3, after filtration, dilutes the dialyzed blood flowing through the third chamber 3. The diluted blood flows out from the third chamber 3.

[0068] It should be noted that in the pre-replacement mode, the replacement fluid enters through the connector of the first chamber 1, effectively diluting toxins in the blood and improving toxin removal efficiency. In the post-replacement mode, the replacement fluid enters through the connector of the third chamber 3, diluting the concentrated blood and further improving toxin removal efficiency. In the mixed replacement mode, the replacement fluid enters through the connectors of both the first chamber 1 and the third chamber 3, combining the advantages of pre-replacement and post-replacement. This ensures efficient utilization of the replacement fluid while reducing the risk of filter clogging, improving treatment flexibility and effectiveness, meeting the personalized needs of different patients, and providing more options and greater flexibility for clinical treatment. This method meets the diverse treatment needs of different patients, improves toxin removal efficiency, dialysate and replacement fluid utilization efficiency, and ensures the safety of dialysis treatment. The specific structure of the three-chamber hemodialysis filter in this method is described in [reference needed]. Figure 1 and Figure 2 The description will not be repeated here.

[0069] In summary, the three-chamber hemodialysis filter provided by this invention meets the needs of various clinical treatment modes, especially for mixed-replacement hemodialysis filtration therapy. It overcomes the limitations of existing dual-chamber filters that can only achieve pre-replacement or post-replacement treatment modes, adapting to the switching requirements of pre-replacement, post-replacement, and mixed-replacement modes, improving treatment flexibility and meeting the personalized needs of different patients. The hemodialysis filtration method of the three-chamber hemodialysis filter provided by this invention satisfies the diverse treatment needs of different patients, improves toxin removal efficiency, dialysate and replacement fluid utilization efficiency, and ensures the safety of dialysis treatment.

[0070] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0071] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0072] The above provides a detailed description of a three-chamber hemodialysis filter and its hemodialysis filtration method provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are merely for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. A three-chamber hemodialysis filter, characterized in that, include: The dialysis filter body includes a first chamber (1), a second chamber (2) and a third chamber (3) arranged coaxially and connected in sequence along the blood flow direction. The first chamber (1), the second chamber (2) and the third chamber (3) are all sealed with corresponding hollow fiber membrane bundles (4). The first chamber (1) and the third chamber (3) are provided with connectors at both ends of their sides. The second chamber (2) is provided with a dialysate inlet (5) and a dialysate outlet (6) at both ends of its side.

2. The three-chamber hemodialysis filter according to claim 1, characterized in that, The connector is provided in multiple ways, and the multiple connectors are evenly arranged around the first chamber (1) and the third chamber (3).

3. The three-chamber hemodialysis filter according to claim 1, characterized in that, The connector includes a first connector (7) and a second connector (8) located on the side of the first chamber (1). One end of the first chamber (1) is provided with a first end cap (9), and the first end cap (9) is provided with a blood inlet.

4. The three-chamber hemodialysis filter according to claim 3, characterized in that, The connector also includes a third connector (10) and a fourth connector (11) located on the side of the third chamber (3). One end of the third chamber (3) is provided with a second end cap (12), and the second end cap (12) is provided with a blood outlet.

5. The three-chamber hemodialysis filter according to claim 1, characterized in that, The first chamber (1), the second chamber (2) and the third chamber (3) are all cylindrical structures. The second chamber (2) is connected to the first chamber (1) and the third chamber (3) through a connector (13).

6. The three-chamber hemodialysis filter according to claim 4, characterized in that, The first end cap (9) and the second end cap (12) are connected by thread or ultrasonic welding to the corresponding first chamber (1) and third chamber (3).

7. The three-chamber hemodialysis filter according to claim 6, characterized in that, When the first end cap (9) and the second end cap (12) are connected to the corresponding first chamber (1) and third chamber (3) by thread, a sealing ring is provided between the first end cap (9) and the first chamber (1), and the sealing ring is also provided between the second end cap (12) and the third chamber (3).

8. The three-chamber hemodialysis filter according to claim 1, characterized in that, The hollow fiber membrane bundle (4) is sealed and bonded to the first chamber (1), the second chamber (2) and the third chamber (3) by polyurethane adhesive.

9. The three-chamber hemodialysis filter according to claim 1, characterized in that, The hollow fiber membrane bundles (4) in the first chamber (1) and the third chamber (3) are one or more of polysulfone, polyethersulfone or polyester polymer composite membranes, and the hollow fiber membrane bundles (4) in the second chamber (2) are one or more of polysulfone, polyethersulfone, polyester polymer composite membrane or triacetate cellulose membrane.

10. A hemodialysis filtration method using a three-chamber hemodialysis filter, characterized in that, Applied to the three-chamber hemodialysis filter according to any one of claims 1-9, the hemodialysis filtration method comprises: The replacement mode is switched to the corresponding mode according to the treatment needs. The replacement modes include anterior replacement mode, posterior replacement mode and hybrid replacement mode. When switching to the pre-displacement mode, the first chamber (1) is filled with replacement fluid, and the second chamber (2) and the third chamber (3) are filled with dialysate. The replacement fluid first enters the first chamber (1) for filtration and dilutes the blood flowing through the first chamber (1). The diluted blood then passes through the second chamber (2) and the third chamber (3) in sequence. The dialysate in the second chamber (2) and the third chamber (3) performs dialysis on the diluted blood. The dialyzed blood then flows out from the third chamber (3). When switching to the post-displacement mode, dialysate is introduced into the first chamber (1) and the second chamber (2) respectively, and replacement fluid is introduced into the third chamber (3). Blood passes through the first chamber (1) and the second chamber (2) in sequence. The dialysate in the first chamber (1) and the second chamber (2) performs dialysis on the blood. The dialyzed blood enters the third chamber (3). The replacement fluid in the third chamber (3) after filtration dilutes the dialyzed blood flowing through the third chamber (3). The diluted blood flows out from the third chamber (3). When switching to the hybrid replacement mode, replacement fluid is introduced into the first chamber (1) and the third chamber (3) respectively, and dialysate is introduced into the second chamber (2). The replacement fluid enters the first chamber (1) and the third chamber (3) respectively for filtration. The replacement fluid in the first chamber (1) dilutes the blood flowing through the first chamber (1). The diluted blood enters the second chamber (2). The dialysate in the second chamber (2) performs dialysis on the diluted blood. The dialyzed blood enters the third chamber (3). The replacement fluid in the third chamber (3) after filtration dilutes the dialyzed blood flowing through the third chamber (3). The diluted blood flows out from the third chamber (3).

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