A dialyzer and a dialysis system

Abstract

The utility model discloses a dialyzer and dialysis system relates to dialysis technical field, wherein, dialyzer, include: casing, inside set hollow channel, support body is hollow structure for tubular, coaxial setting in hollow channel, membrane filament bundle includes the hollow channel in the inside and outside of the support body pipe wall respectively filled with a plurality of membrane filaments, and this dialyzer and dialysis system increase the support body, and effectively solve the tunnel effect when dialysate flows through the membrane filament bundle, guarantee the dialysis sufficiency of patient.

Description

Technical Field

[0001] This utility model relates to the field of dialysis technology, and more specifically, to a dialyzer. Furthermore, this utility model also relates to a dialysis system including the aforementioned dialyzer. Background Technology

[0002] Hemodialysis is currently the most critical renal replacement therapy. Low molecular weight uremic toxins are transferred from the blood chamber to the dialysate chamber through diffusion. In this process, the hollow fiber membrane is one of the core elements that determines the overall adequacy of dialysis.

[0003] However, in practical applications, when the dialysate enters the dialysate chamber from the inlet at one end of the dialyzer, its flow velocity increases accordingly as the flow space gradually narrows. At this time, the high-speed dialysate flowing through the outer region of the membrane bundle generates shear force, causing the outer membrane fibers to move towards the central region, ultimately leading to an increase in the membrane fiber packing density in the central region of the membrane bundle. During the flow process, the fluid preferentially passes through the outer region of the membrane bundle with a lower membrane fiber packing density, and then flows radially into the center of the membrane bundle, resulting in a low dialysate flow velocity in the central region of the membrane bundle, which in turn causes uneven dialysate flow distribution and produces a dialysate-side tunneling effect.

[0004] Because the effective contact area of ​​the dialysate on the cross-section of the membrane bundle is reduced and unevenly distributed, and the blood flow velocity within the membrane bundle is less affected by the tunneling effect, the tunneling effect causes a mismatch between the dialysate flow rate and the blood flow rate, which in turn leads to a decrease in solute clearance efficiency and affects the adequacy of dialysis for patients.

[0005] In summary, how to solve the tunneling effect when dialysate flows through the membrane fiber bundle in the dialyzer is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0006] In view of this, the purpose of this utility model is to provide a dialyzer that adds a support body to effectively solve the tunneling effect when the dialysate flows through the membrane fiber bundle, thereby ensuring the adequacy of dialysis for patients.

[0007] Another objective of this invention is to provide a dialysis system including the aforementioned dialyzer, which has the same technical features and can solve the same technical problems.

[0008] To achieve the above objectives, this utility model provides the following technical solution:

[0009] A dialyzer, comprising:

[0010] The shell has a hollow internal channel;

[0011] The support body is a tubular hollow structure, coaxially arranged within the hollow channel;

[0012] A membrane filament bundle, comprising several membrane filaments, is respectively filled in the hollow channels on the inner and outer sides of the support tube wall.

[0013] Preferably, the outer diameter of the support is K1 times the inner diameter of the hollow channel, where 1 / 3 ≤ K1 ≤ 2 / 3.

[0014] Preferably, the supporting rigidity of the middle section of the support body is greater than that of the two end sections.

[0015] Preferably, the hollowing ratio of the middle section of the support is less than that of the two end sections.

[0016] Preferably, one end of the support body is provided with an inlet fixing ring, and the inlet fixing ring is integrally formed with the support body;

[0017] The inlet fixing ring has a wide opening structure, and the minimum inner diameter of the inlet fixing ring is equal to the inner diameter of the support body.

[0018] Preferably, the angle between the generatrix of the conical surface of the inlet fixing ring and the end face of the support is α, where 94°≤α≤99°;

[0019] The maximum inner diameter of the inlet fixing ring is K2 times the inner diameter of the support body, where 1.07 ≤ K2 ≤ 1.16.

[0020] Preferably, an outlet fixing ring is provided at the other end of the support body, and the outlet fixing ring is integrally formed with the support body;

[0021] The outlet fixing ring has a constricted opening structure, and the maximum outer diameter of the outlet fixing ring is equal to the outer diameter of the support body.

[0022] Preferably, the angle between the generatrix of the conical surface of the outlet fixing ring and its own end face is b, 94°≤b≤99°;

[0023] The minimum inner diameter of the outlet fixing ring is K3 times the inner diameter of the support body, where 0.84≤K3≤0.93.

[0024] Preferably, end caps are provided at both ends of the housing, and the end caps are provided with flow ports that communicate with the internal channels of the membrane filaments;

[0025] The length of the support is not greater than the length of the membrane fiber bundle, and the support is fixedly connected to the end of the membrane fiber bundle;

[0026] Liquid flow ports are provided at both ends of the side of the shell, which are connected to the hollow channel.

[0027] A dialysis system comprising the dialyzer described in any one of the preceding claims.

[0028] The dialyzer provided by this invention has at least the following advantages compared with the prior art:

[0029] 1. By embedding a support body in the hollow channel of the shell and filling the inner and outer walls of the support body with membrane fibers, the support body provides radial support to the outer membrane fibers, thereby preventing the membrane fibers from moving towards the central area after being subjected to the shear force of the dialysate. This prevents the filling density in the central area of ​​the membrane fiber bundle from increasing, reduces the difference in dialysate flow rate between the central area and the peripheral area, and ensures a stable relationship between the blood flow rate inside the membrane fibers and the dialysate flow rate outside the membrane fibers, thus ensuring adequate dialysis for the patient.

[0030] 2. The support adopts a tubular hollow structure, which provides radial support to the external membrane fibers while not affecting the exchange of dialysate between the inner and outer sides of the tube wall, thus reducing the difference in dialysate flow rate between the central and outer regions of the membrane fiber bundle.

[0031] The dialysis system provided by this utility model includes the dialyzer described above and has the same beneficial effects. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the specific dialyzer provided by this utility model;

[0034] Figure 2 This is a cross-sectional schematic diagram of the specific dialyzer provided by this utility model;

[0035] Figure 3 A schematic diagram of the specific support structure provided by this utility model;

[0036] Figure 4 This is a front view of the specific support body provided by this utility model.

[0037] In the picture:

[0038] 1. Inlet retaining ring; 2. Support body; 3. Outlet retaining ring; 4. Shell; 5. End cap; 6. Membrane fiber.

[0039] 'a' is the angle between the generatrix of the cone surface of the inlet fixing ring and the end face of the support body;

[0040] b is the angle between the generatrix of the cone surface of the outlet fixed ring and its own end face;

[0041] d1 is the maximum inner diameter of the inlet retaining ring;

[0042] d2 is the inner diameter of the support;

[0043] d3 is the minimum inner diameter of the outlet retaining ring. Detailed Implementation

[0044] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0045] The core of this invention is to provide a dialyzer that adds a support body to effectively solve the tunneling effect when the dialysate flows through the membrane fiber bundle, thus ensuring adequate dialysis for patients.

[0046] Another core aspect of this invention is to provide a dialysis system that includes the aforementioned dialyzer, possessing the same technical features and capable of solving the same technical problems.

[0047] Please refer to Figures 1-4 A dialyzer comprising:

[0048] Shell 4, with a hollow channel inside;

[0049] Support 2 is a tubular hollow structure, coaxially arranged inside the hollow channel;

[0050] The membrane fiber bundle, comprising several membrane fibers 6, is filled in the hollow channels on the inner and outer sides of the support body 2.

[0051] like Figure 1 As shown, the shell 4 is a tubular structure with a hollow channel inside. The hollow channel is filled with membrane fiber bundles. The outer diameter of the support 2 is smaller than the inner diameter of the hollow channel, and the support 2 is coaxially arranged in the hollow channel. The inside and outside of the support 2 are filled with membrane fibers 6.

[0052] When the dialysate enters the hollow channel of the housing 4, it flows from the inlet end to the outlet end. Part of the dialysate flows axially along the membrane fibers, and part flows radially towards the central region of the membrane fiber bundle. When the outer membrane fibers 6 are subjected to radial shear force, the support 2 provides a supporting force in the opposite direction to the outer membrane fibers 6, thereby preventing the outer membrane fibers 6 from collapsing towards the central region. This ensures that the filling density of the membrane fibers 6 in the central region of the membrane fiber bundle does not change due to the movement of the outer membrane fibers 6, allowing part of the dialysate to flow rapidly radially into the central region of the membrane fiber bundle. This reduces the difference in dialysate flow rate between the central and outer regions of the membrane fiber bundle, ensuring a stable relationship between the blood flow rate inside the membrane fibers 6 and the dialysate flow rate outside the membrane fibers 6, thus guaranteeing adequate dialysis for the patient.

[0053] Moreover, the support body 2 is arranged coaxially with the hollow channel, which ensures that the radial shear force on the outer periphery of the support body 2 is equal in all directions, thus achieving force balance and ensuring the stability of the relative position of the support body 2 and the shell 4 during use.

[0054] In some embodiments, the outer diameter of the support 2 is K1 times the inner diameter of the hollow channel, where 1 / 3 ≤ K1 ≤ 2 / 3.

[0055] like Figure 2 As shown, the outer diameter of the support 2 is set to 1 / 3, 1 / 2, or 2 / 3 of the inner diameter of the hollow channel, so that it provides radial support to the membrane filaments 6 in the membrane bundle and prevents them from undergoing radial displacement.

[0056] If the outer diameter of the support body 2 is set to be 1 / 2 of the inner diameter of the hollow channel, then all membrane fibers 6 located outside the support body 2 will be radially supported. When the dialysate flows through the membrane fibers 6 and generates radial shear force, the support body 2 can provide radial support to the membrane fibers 6 located outside the support body 2, preventing them from radially compressing the membrane fibers 6 located inside the support body 2. This ensures that the membrane fiber packing density of the membrane fiber bundle inside the support body 2 does not change, maintains the gap between adjacent membrane fibers 6, and keeps the resistance to dialysate flow stable. This reduces the difference in dialysate flow rate between the membrane fiber bundle inside the support body 2 and the membrane fiber bundle outside the support body 2, thereby making the dialysate flow rate of the membrane fiber bundle in each area of ​​the hollow channel balanced and matching the blood flow rate in the membrane fibers 6. This ensures the uniformity of substance exchange between blood and dialysate and guarantees the adequacy of dialysis for the patient.

[0057] In some embodiments, the support rigidity of the middle section of the support body 2 is greater than that of the two end sections.

[0058] In practical use, such as Figure 1As shown, the dialysate inlet and outlet are located at the two ends of the side of the shell 4, respectively. The dialysate tends to flow quickly from the inlet to the outlet, allowing the dialysate near the inlet and outlet ends to fully cover the surrounding membrane fiber area, resulting in a high volume distribution. However, in the middle section of the dialyzer, especially in the central area of ​​the membrane fiber bundle, the dialysate has difficulty reaching smoothly, resulting in the lowest volume distribution. The membrane fibers 6 inside the shell 4 are arranged in a regular and conventional manner. If there is no special structure to disperse the filling of the membrane fibers 6 in the middle section, the filling will be more dense, which further hinders the dialysate from penetrating to the center of the membrane fiber bundle, resulting in a low dialysate volume in the middle section.

[0059] Meanwhile, in order to make the inner lumen of the membrane filament 6 connected with the blood channel, the two ends of the membrane filament bundle are usually fixed to the two ends of the shell 4 with sealant and cut off at the ends. The shear deformation resistance of the fixed two end sections is greater than that of the middle section. Therefore, when designing the support body 2, it is preferable to increase the support rigidity of the middle section to avoid radial displacement of the membrane filament bundle outside the support body 2.

[0060] In some embodiments, the hollowing ratio of the middle section of the support 2 is less than that of the two end sections.

[0061] like Figure 4 As shown, the hollowing ratio of the middle section of the support body 2 is reduced to improve the support rigidity of the middle section;

[0062] In some embodiments, the same function can be achieved by increasing the wall thickness of the middle section or by adding annular ribs to the middle section.

[0063] like Figure 4 As shown, the shape of the perforated part of the support body 2 is preferably, but not limited to, rhombus, circle, ellipse and triangle. By adjusting the perforation rate, i.e. the perforation density, the mechanical support strength and dialysate permeability of the support body 2 are adjusted. Under the premise of ensuring the dialysate permeability, sufficient radial support force is provided for the membrane filaments 6 outside the support body 2 to prevent them from moving towards the central area under the action of radial shear force.

[0064] If the total opening ratio on the support body 2 is 72%~90%, preferably 81%~89%, the support body 2 is divided into three parts I, II and III along the length of the membrane filament 6. The opening ratio of the second part is 72%~80%, preferably 81%~84%, and the opening ratio of the other two parts is 80%~90%, preferably 84%~89%. That is, by reducing the opening ratio of the second part, the mechanical support performance of the second part is improved.

[0065] In some embodiments, an inlet fixing ring 1 is provided at one end of the support body 2, and the inlet fixing ring 1 is integrally formed with the support body 2;

[0066] The inlet fixing ring 1 has a wide opening structure, and the minimum inner diameter of the inlet fixing ring 1 is equal to the inner diameter of the support body 2.

[0067] like Figure 2 , Figure 3 and Figure 4 As shown, an inlet fixing ring 1 is provided at the inlet end of the support body 2 to increase the end rigidity of the support body 2 and improve its mechanical support performance. At the same time, the inlet fixing ring 1 adopts a wide-mouth structure, which facilitates the insertion of the membrane filament 6 inside the support body 2. Moreover, the minimum inner diameter of the inlet fixing ring 1 is equal to the inner diameter d2 of the support body 2, that is, the inner wall of the connection between the inlet fixing ring 1 and the support body 2 is smooth, which helps to reduce the insertion resistance of the membrane filament 6.

[0068] In some embodiments, the angle between the generatrix of the conical surface of the inlet fixing ring 1 and the end face of the support 2 is α, where 94°≤α≤99°;

[0069] The maximum inner diameter of the inlet fixing ring 1 is K2 times the inner diameter of the support body 2, where 1.07≤K2≤1.16.

[0070] like Figure 4 As shown, the maximum inner diameter d1 of the inlet fixing ring 1 is greater than the minimum inner diameter, and the minimum inner diameter of the inlet fixing ring 1 is equal to the inner diameter d2 of the support. Therefore, the inlet fixing ring 1 has a conical structure as a whole, and the maximum inner diameter is K2 times the minimum inner diameter. In the design, the axial length of the inlet fixing ring 1 is obtained by designing the K2 value and the included angle α. This satisfies the radial support of the membrane filament 6 while reducing interference with the radial transmission of the dialysate.

[0071] In some embodiments, an outlet fixing ring 3 is provided at the other end of the support body 2, and the outlet fixing ring 3 is integrally formed with the support body 2.

[0072] The outlet fixing ring 3 has a constricted opening structure, and the maximum outer diameter of the outlet fixing ring 3 is equal to the outer diameter of the support body 2.

[0073] like Figure 2 , Figure 3 and Figure 4 As shown, an outlet fixing ring 3 is provided at the outlet end of the support body 2 to increase the end rigidity of the support body 2 and improve its mechanical support performance. The maximum inner diameter of the outlet fixing ring 3 is equal to the inner diameter d2 of the support body 2, and the minimum inner diameter d3 of the outlet fixing ring 3 is less than d2. That is, the outlet fixing ring 3 adopts a constricted structure, which can axially limit the membrane filaments 6 inside the support body 2. At the same time, the outer periphery of the outlet fixing ring 3 and the inner wall of the hollow channel of the shell 4 form a wide opening, which facilitates the insertion of the membrane filaments 6 between the support body 2 and the inner wall of the hollow channel of the shell 4 from the outlet end. Moreover, the maximum outer diameter of the outlet fixing ring 3 is equal to the outer diameter of the support body 2. That is, the outer surface of the connection position between the outlet fixing ring 3 and the support body 2 is smooth, which helps to reduce the insertion resistance of the membrane filaments 6.

[0074] In some embodiments, the angle between the generatrix of the conical surface of the outlet fixing ring 3 and its own end face is b, where 94°≤b≤99°;

[0075] The minimum inner diameter of the outlet fixing ring 3 is K3 times the inner diameter of the support body 2, where 0.84≤K3≤0.93.

[0076] like Figure 4 As shown, the outlet fixing ring 3 has an overall conical structure, and the minimum inner diameter is K3 times the maximum inner diameter. During the design, the axial length of the outlet fixing ring 3 is obtained by designing the K3 value and the included angle b, which satisfies the radial support of the membrane filament 6 while reducing interference with the radial transmission of the dialysate.

[0077] In some embodiments, end caps 5 are respectively provided at both ends of the housing 4, and the end caps 5 are provided with flow ports, which are connected to the internal channels of the membrane filaments 6.

[0078] The length of the support 2 is not greater than the length of the membrane fiber bundle, and the support 2 is fixedly connected to the end of the membrane fiber bundle;

[0079] Liquid flow ports are provided at both ends of the side of the shell 4, which are connected to the hollow channel.

[0080] like Figure 1 As shown, both end caps 5 are provided with flow ports, which are connected to the inside of the membrane fiber 6 to allow blood to flow in the membrane fiber 6. Liquid flow ports are provided at both ends of the side of the shell 4 for the entry and exit of dialysate.

[0081] Preferably, the length of the support 2 is equal to the length of the membrane fiber bundle, and the ends of the support 2 and the ends of the membrane fiber bundle are fixedly disposed at both ends of the housing 4 by sealant.

[0082] Under in vitro conditions, the connection device was connected to the dialyzer of this application and a regular dialyzer, respectively. Vitamin B12 solution was used as the simulated solution, and the blood flow rate QB=200 mL / min, dialysate flow rate QD=500 mL / min, and dehydration rate QF=10 mL / min were set. Samples were taken from the inlet and outlet of the blood chamber. After the operation was stable for 10 minutes, the vitamin B12 clearance rate was tested according to industry standard YY0053.

[0083] In this application, the dialyzer has K1=1 / 2. The inlet fixing ring 1, the support body 2, and the outlet fixing ring 3 are integrally injection molded and are made of the same material as the shell 4, such as polypropylene or polycarbonate. The included angle a of the inlet fixing ring 1 is 97° and the included angle b of the outlet fixing ring 3 is 95°. The rest are the same as the parameters of a conventional dialyzer.

[0084] The test results are as follows:

[0085] Using the dialyzer described in this application, the vitamin B12 clearance rate was 158.27 mL / min;

[0086] A standard dialyzer showed a vitamin B12 clearance rate of 140.66 mL / min.

[0087] In summary, the vitamin B12 clearance rate using the dialyzer described in this application is significantly higher than that of a conventional dialyzer.

[0088] In addition to the dialyzers disclosed in the above embodiments, this utility model also provides a dialysis system including the dialyzers described above. The structures of other parts of the dialysis system are described in the prior art and will not be repeated here.

[0089] 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.

[0090] The dialyzer and dialysis system provided by this utility model have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this utility model. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this utility model. It should be noted that those skilled in the art can make several improvements and modifications to this utility model without departing from the principles of this utility model, and these improvements and modifications also fall within the protection scope of the claims of this utility model.

Claims

1. A dialyzer, characterized in that, include: The shell (4) has a hollow channel inside; The support (2) is a tubular hollow structure, coaxially arranged in the hollow channel; The membrane fiber bundle, comprising several membrane fibers (6), is filled in the hollow channels on the inner and outer sides of the support (2) tube wall.

2. The dialyzer according to claim 1, characterized in that, The outer diameter of the support (2) is K1 times the inner diameter of the hollow channel, and 1 / 3≤K1≤2 / 3.

3. The dialyzer according to claim 1, characterized in that, The support rigidity of the middle section of the support body (2) is greater than that of the two end sections.

4. The dialyzer according to claim 1, characterized in that, The hollowing rate of the middle section of the support (2) is less than that of the two end sections.

5. The dialyzer according to claim 1, characterized in that, An inlet fixing ring (1) is provided at one end of the support body (2), and the inlet fixing ring (1) is integrally formed with the support body (2); The inlet fixing ring (1) has a wide opening structure, and the minimum inner diameter of the inlet fixing ring (1) is equal to the inner diameter of the support body (2).

6. The dialyzer according to claim 5, characterized in that, The angle between the generatrix of the conical surface of the inlet fixing ring (1) and the end face of the support (2) is α, 94°≤a≤99°; The maximum inner diameter of the inlet fixing ring (1) is K2 times the inner diameter of the support (2), where 1.07≤K2≤1.

16.

7. The dialyzer according to claim 1, characterized in that, An outlet fixing ring (3) is provided at the other end of the support body (2), and the outlet fixing ring (3) is integrally formed with the support body (2); The outlet fixing ring (3) has a constricted opening structure, and the maximum outer diameter of the outlet fixing ring (3) is equal to the outer diameter of the support body (2).

8. The dialyzer according to claim 7, characterized in that, The angle between the generatrix of the cone surface of the outlet fixing ring (3) and its own end face is b, 94°≤b≤99°; The minimum inner diameter of the outlet fixing ring (3) is K3 times the inner diameter of the support (2), where 0.84≤K3≤0.

93.

9. The dialyzer according to any one of claims 1-8, characterized in that, The shell (4) is provided with end caps (5) at both ends, and the end caps (5) are provided with flow ports, which are connected to the internal channels of the membrane filaments (6); The length of the support (2) is not greater than the length of the membrane fiber bundle, and the support (2) is fixedly connected to the end of the membrane fiber bundle; Liquid flow ports are provided at both ends of the side of the shell (4), which are connected to the hollow channel.

10. A dialysis system, characterized in that, Includes the dialyzer as described in any one of claims 1-9.

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