Long-term hemodialysis catheter tip structure

Abstract

The utility model discloses a long -term hemodialysis catheter tip structure, including the pipe body, the pipe cavity of pipe body is provided with the baffle along the axial direction extension of pipe body, the baffle will the pipe cavity divide into the artery cavity and the venous cavity of independent each other, the end of pipe body is provided with C / D type tip or S type tip. The present application improves the hemodialysis efficiency from the physical structure, reduces the catheter thrombosis, reduces the infection incidence.

Description

Technical Field

[0001] This utility model relates to the field of medical catheter instrument technology, specifically to a tip structure for a long-term hemodialysis catheter. Background Technology

[0002] Hemodialysis is a crucial treatment for patients with end-stage renal disease, and the hemodialysis catheter is the essential pathway for this process. Currently available long-term hemodialysis catheters have both venous and arterial lumenes. When a patient needs hemodialysis, blood is drawn from the patient's body through the arterial lumen of the catheter to the hemodialysis machine. The hemodialysis machine operates based on the properties of a semipermeable membrane, allowing only small molecules to pass through while large molecules cannot. During dialysis, blood flows through the thin tubing inside the dialyzer, while the outside of the dialyzer is the dialysate, creating a concentration gradient. Harmful small molecules in the blood, such as urea nitrogen and creatinine, diffuse from the blood into the dialysate due to this concentration gradient, while water also permeates out, thus removing excess fluid. Simultaneously, electrolytes and other beneficial substances in the dialysate diffuse into the blood to maintain electrolyte balance. Finally, the purified blood is returned to the patient through the venous lumen of the catheter.

[0003] Chinese utility model patent CN212575345U discloses a hemodialysis catheter with a first through-hole and a second through-hole respectively on the arterial and venous cavities. This side-hole structure effectively prevents the hemodialysis catheter from adhering to the blood vessel wall, thus preventing reduced flow or even blockage. However, the side holes can cause blood to stagnate locally. This stagnant blood, in prolonged contact with the catheter surface, further activates the coagulation system, eventually leading to thrombus formation. Once a thrombus forms, it gradually blocks the catheter, and in severe cases, it may even detach and enter the bloodstream, endangering the patient's life. Existing technologies mostly rely on anticoagulant coatings to reduce the risk of thrombosis, but these coatings may detach or trigger allergic reactions.

[0004] Furthermore, traditional long-term hemodialysis catheters often have small openings, excessively rigid tips, or sharp edges. During blood flow, these small openings can easily become blocked, reducing blood flow and causing further blockages, resulting in low dialysis efficiency. Over long-term use, these sharp tips may also puncture the vascular endothelium, causing not only pain but also inflammation and increasing the risk of infection.

[0005] Due to defects in the tip structure of traditional long-term hemodialysis catheters, uneven pressure between the arterial and venous cavities can easily occur, leading to catheter deformation or blood flow disturbances and affecting dialysis efficiency. Utility Model Content

[0006] Therefore, this utility model provides a long-term hemodialysis catheter tip structure to solve the problems of small catheter tip opening, easy thrombosis caused by side holes, and hemodynamic instability in the existing technology.

[0007] To achieve the above objectives, this application provides the following technical solution:

[0008] A long-term hemodialysis catheter tip structure includes a tube body, in which a baffle extending along the axial direction of the tube body is disposed in the lumen of the tube body, the baffle dividing the lumen into an independent arterial lumen and a venous lumen, and the end of the tube body is provided with a C / D type tip or an S type tip.

[0009] Furthermore, the arterial cavity and the venous cavity are arranged symmetrically.

[0010] Furthermore, the port of the C / D-shaped tip corresponding to the venous cavity is a C-shaped opening, and the port corresponding to the arterial cavity is a D-shaped opening.

[0011] Furthermore, the port of the corresponding venous cavity of the C / D-shaped tip is provided with a first guide surface, and the port of the corresponding arterial cavity of the C / D-shaped tip is provided with a second guide surface. The angle between the first guide surface, the second guide surface and the axial direction of the tube body is 30°-60°, and the distance between the second guide surface and the first guide surface is 18mm-30mm.

[0012] Furthermore, the port of the S-shaped tip corresponding to the venous cavity is an S-shaped opening, and the port of the S-shaped tip corresponding to the arterial cavity is an S-shaped opening.

[0013] Furthermore, the S-shaped tip is a symmetrical double S-shaped tip or a double S-shaped tip.

[0014] Furthermore, the symmetrical double S-shaped tip is symmetrically arranged relative to the baffle, the distance between the vertex of the S-side of the symmetrical double S-shaped tip and the starting end of the baffle is 3mm-9mm, and the distance between the low point of the S-side of the symmetrical double S-shaped tip and the starting end of the baffle is 6mm-18mm.

[0015] Furthermore, in the double S-shaped tip structure, the distance from the vertex of the S-side of the double S-shaped tip corresponding to the venous cavity to the starting end of the baffle is 3mm-9mm, and the distance from the lowest point of the S-side of the double S-shaped tip corresponding to the venous cavity to the starting end of the baffle is 6mm-18mm; the distance from the vertex of the S-side of the double S-shaped tip corresponding to the arterial cavity to the starting end of the baffle is 14mm-18.5mm, and the distance from the lowest point of the S-side of the double S-shaped tip corresponding to the arterial cavity to the starting end of the baffle is 18mm-24mm.

[0016] Furthermore, the port edge of the tip structure of the long-term hemodialysis catheter is rounded to form a smooth transition.

[0017] Furthermore, it also includes a polyester sleeve, a catheter hub, a catheter hub connector, a catheter clamp, an arterial lumen extension tube, a venous lumen extension tube, and a Luer connector. The polyester sleeve is fitted over the outside of the tube body. The end of the tube body away from the C / D-shaped tip or S-shaped tip is integrally formed with the catheter hub. The catheter hub connector is connected to the catheter hub. The arterial lumen extension tube is connected to the arterial lumen through the catheter hub connector. The venous lumen extension tube is connected to the venous lumen through the catheter hub connector. The catheter clamp and the Luer connector are respectively sequentially provided on the arterial lumen extension tube and the venous lumen extension tube. The Luer connector is located at the end of the arterial lumen extension tube and the venous lumen extension tube.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects:

[0019] 1. This application improves the efficiency of hemodialysis from a physical structure perspective, reduces catheter thrombosis, and lowers the incidence of infection. Essentially, it increases the contact area between the drainage and reinfusion ports of long-term hemodialysis catheters and blood, thereby improving hemodialysis efficiency and preventing patients from forming thrombi that block the catheter during hemodialysis.

[0020] 2. The symmetrical double-S-shaped tip ensures more uniform blood flow, reduces blood recirculation between the arterial and venous lumens, improves dialysis efficiency, reduces blood stagnation and turbulence, lowers the likelihood of thrombosis, and extends catheter lifespan. The cross-sectional area of ​​the arterial lumen in double-S-shaped and C / D-shaped tips is larger than that in the venous lumen. This results in a smaller difference in horizontal pressure between the arterial and venous lumens during dialysis, reducing catheter deformation caused by pressure imbalances between the two lumens.

[0021] 3. This application features a rounded port design for the tip structure to avoid damage to the vascular endothelium caused by excessive rigidity or sharp edges of the catheter tip. This design offers advantages such as reduced infection risk, improved dialysis efficiency, and enhanced stability.

[0022] The above overview is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of this application will become readily apparent from the accompanying drawings and the following detailed description. Attached Figure Description

[0023] To more intuitively illustrate the prior art and this application, exemplary drawings are provided below. It should be understood that the specific shapes and structures shown in the drawings should not generally be regarded as limiting conditions for implementing this application; for example, based on the technical concept disclosed in this application and the exemplary drawings, those skilled in the art are able to easily make conventional adjustments or further optimizations to the addition / reduction / classification, specific shapes, positional relationships, connection methods, size ratios, etc. of certain units (components).

[0024] Figure 1 A schematic diagram of the structure of a long-term hemodialysis catheter provided by this utility model;

[0025] Figure 2 A schematic diagram of the C / D type tip structure of a long-term hemodialysis catheter tip structure provided by this utility model;

[0026] Figure 3 A top view schematic diagram of the C / D type tip structure of a long-term hemodialysis catheter tip structure provided by this utility model;

[0027] Figure 4 A three-dimensional structural diagram of a C / D type tip for a long-term hemodialysis catheter tip structure provided by this utility model;

[0028] Figure 5 A top view schematic diagram of a symmetrical double-S-shaped tip structure of a long-term hemodialysis catheter tip structure provided by this utility model;

[0029] Figure 6 A three-dimensional structural diagram of a symmetrical double-S-shaped tip for a long-term hemodialysis catheter tip structure provided by this utility model;

[0030] Figure 7 A top view schematic diagram of the double S-shaped tip structure of a long-term hemodialysis catheter tip structure provided by this utility model;

[0031] Figure 8 A bottom view of the double S-shaped tip structure of a long-term hemodialysis catheter tip structure provided by this utility model;

[0032] Figure 9 This is a three-dimensional structural diagram of a double S-shaped tip for a long-term hemodialysis catheter tip structure provided by this utility model.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Tube body; 2. Arterial cavity; 3. Venous cavity; 4. Polyester sheath; 5. Catheter seat; 6. Catheter seat connector; 7. Catheter clamp; 8. Arterial cavity extension tube; 9. Venous cavity extension tube; 10. Luer connector. Detailed Implementation

[0035] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this application. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0036] Example 1

[0037] like Figure 1 As shown, a long-term hemodialysis catheter tip structure includes a polyester sleeve 4 (also known as a clasp) fitted onto the outside of the catheter body 1. The polyester sleeve 4 can adhere to the subcutaneous tissue, fixing the catheter in place. The adhered tissue acts as a barrier, isolating bacteria and reducing the risk of infection. One end of the catheter body 1 is integrally formed with the catheter seat 5. The catheter seat connector 6 connects to the catheter seat 5. The arterial lumen extension tube 8 is connected to the arterial lumen 2 via the catheter seat connector 6, and the venous lumen extension tube 9 is connected to the venous lumen 3 via the catheter seat connector 6. A catheter clamp 7 and a Luer connector 10 are sequentially installed on the arterial lumen extension tube 8 and the venous lumen extension tube 9, respectively. The Luer connector 10 is located at the ends of the arterial lumen extension tube 8 and the venous lumen extension tube 9.

[0038] like Figures 2-4As shown, a baffle extending along the axial direction of the tube body 1 is provided in the lumen of the tube body 1, dividing the lumen into an independent arterial cavity 2 and a venous cavity 3, which are symmetrically arranged. A C / D-shaped tip is provided at the end of the tube body 1 away from the catheter seat 5. In this embodiment, the C / D-shaped tip is formed by hot-melt process, precision cutting tool, or laser cutting, and processed according to the designed length and shape of the catheter body. The port of the venous cavity 3 is beveled to form a first guide surface, thereby forming a C-shaped opening at the port of the venous cavity 3; the port of the arterial cavity 2 is beveled to form a second guide surface, thereby forming a D-shaped opening at the port of the arterial cavity 2. The angles between the first guide surface, the second guide surface, and the axial direction of the tube body 1 are both 30°-60°, and the distance between the second guide surface and the first guide surface is 18mm-30mm. In this embodiment, appropriate angles and spacing guide blood in the arterial cavity 2 and venous cavity 3 to flow at a more reasonable angle and direction, reducing turbulence and vortex formation at the tip. This allows for smoother blood drainage and reinfusion, improving the efficiency of substance exchange between blood and dialysate during hemodialysis, thereby enhancing the overall dialysis effect. When blood flow is stable and orderly, clotting components such as platelets are less likely to aggregate, maintaining good blood flow and reducing the possibility of thrombus formation at the catheter tip. Reduced thrombus formation can prevent catheter blockage, extend catheter lifespan, and reduce the frequency and risk of catheter replacements due to catheter problems. Rounding the tip ensures a smooth tip, preventing damage to the vascular endothelium.

[0039] Example 2

[0040] Example 2 is basically the same as Example 1, with the main difference being as follows: Figures 5-6 As shown, a symmetrical double S-shaped tip is provided at the end of the tube body 1 away from the catheter seat 5. The port of the venous cavity 3 corresponding to the S-shaped tip is an S-shaped opening, and the port of the arterial cavity 2 corresponding to the S-shaped tip is also an S-shaped opening. The S-shaped opening design makes blood flow more uniform and reduces blood recirculation. The symmetrical double S-shaped tips are symmetrically arranged relative to the baffle. For example, the distance from the vertex of the S-side of the venous cavity 3 to the starting end of the baffle is 3mm-9mm, and the distance from the lowest point of the S-side of the venous cavity 3 to the starting end of the baffle is 6mm-18mm. Because of the symmetrical arrangement, the distance from the vertex of the S-side of the arterial cavity 2 to the starting end of the baffle is 3mm-9mm, and the distance from the lowest point of the S-side of the arterial cavity 2 to the starting end of the baffle is 6mm-18mm.

[0041] In this embodiment, the symmetrical double S-shaped tip is formed by thermoforming, precision machining, or laser cutting, and the ends of the catheter's venous cavity 3 and arterial cavity 2 are cut according to the designed length and shape. The special shape of the symmetrical double S-shaped tip allows blood to be more evenly distributed in the arterial cavity 2 and venous cavity 3 as it flows through the catheter tip. Compared to other tip shapes, this design avoids localized excessively fast or slow blood flow, reduces turbulence and eddies in blood flow, and significantly reduces blood recirculation between the arterial and venous cavities, thereby improving the stability and smoothness of blood flow within the catheter. During hemodialysis, the catheter will not exert excessive pressure or friction on the vessel wall due to uneven force, thus reducing the risk of damage to the vascular endothelium, protecting the integrity of the blood vessel, and reducing the probability of complications such as inflammation and stenosis caused by vascular damage. Combined with the rounded tip, the catheter tip becomes smoother, further preventing scratches or punctures to the vascular endothelium caused by excessive tip rigidity or sharp edges. This not only reduces the risk of infection but also minimizes damage to the blood vessel walls, providing better protection for the vascular access of long-term hemodialysis patients and helping to maintain normal vascular function.

[0042] Example 3

[0043] Example 3 is basically the same as Example 2, with the main difference being as follows: Figures 7-9 As shown, a double S-shaped tip is provided at the end of the tube body 1 away from the catheter seat 5. In the double S-shaped tip structure, the distance from the vertex of the S-side of the double S-shaped tip of the venous lumen 3 to the starting end of the baffle is 3mm-9mm, and the distance from the lowest point of the S-side of the double S-shaped tip of the venous lumen 3 to the starting end of the baffle is 6mm-18mm; the distance from the vertex of the S-side of the double S-shaped tip of the arterial lumen 2 to the starting end of the baffle is 14mm-18.5mm, and the distance from the lowest point of the S-side of the double S-shaped tip of the arterial lumen 2 to the starting end of the baffle is 18mm-24mm.

[0044] In this embodiment, the special design of the double S-shaped tips ensures that the vertices of the S-shaped edges of the venous cavity 3 and the arterial cavity 2 are within a specific distance range from the starting end of the baffle. This design provides a more rational path for blood flow within the catheter. During hemodialysis, it guides blood to flow more smoothly into the venous cavity 3 and the arterial cavity 2 respectively, reducing turbulence and eddies within the catheter, thereby improving the efficiency of hemodialysis and ensuring the stability of blood flow during dialysis.

[0045] Under the impact of blood flow, the double S-shaped tip, through its unique structure, can better disperse the force of blood flow, reducing catheter swaying and displacement, ensuring that the catheter remains in the proper position during long-term use and maintaining normal hemodialysis function. The double S-shaped tip is also formed using a thermoforming process, precision machining, or laser cutting. The catheter's venous lumen 3 and arterial lumen 2 ports are cut according to the designed length and shape, and the tip is subsequently rounded to make it smoother.

[0046] The technical features of the above embodiments can be combined in any way (as long as there is no contradiction in the combination of these technical features). For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; these embodiments not explicitly written should also be considered to be within the scope of this specification.

Claims

1. A long-term hemodialysis catheter tip structure, characterized by, The tube includes a tube body (1), and a baffle extending along the axial direction of the tube body (1) is provided in the lumen of the tube body (1). The baffle divides the lumen into an independent arterial cavity (2) and a venous cavity (3). The end of the tube body (1) is provided with a C / D type tip or an S type tip.

2. The long-term hemodialysis catheter tip structure of claim 1, wherein, The arterial cavity (2) and the venous cavity (3) are arranged symmetrically.

3. The long-term hemodialysis catheter tip structure of claim 1, wherein, The port of the C / D-shaped tip corresponding to the venous cavity (3) is a C-shaped opening, and the port corresponding to the arterial cavity (2) is a D-shaped opening.

4. The long-term hemodialysis catheter tip structure of claim 3, wherein, The port of the corresponding venous cavity (3) of the C / D-type tip is provided with a first guide surface, and the port of the corresponding arterial cavity (2) of the C / D-type tip is provided with a second guide surface. The angle between the first guide surface, the second guide surface and the axial direction of the tube (1) is 30°-60°, and the distance between the second guide surface and the first guide surface is 18mm-30mm.

5. The long-term hemodialysis catheter tip structure of claim 1, wherein, The port of the S-shaped tip corresponding to the venous cavity (3) is an S-shaped opening, and the port of the S-shaped tip corresponding to the arterial cavity (2) is an S-shaped opening.

6. The long-term hemodialysis catheter tip structure of claim 5, wherein, The S-shaped tip is a symmetrical double S-shaped tip or a double S-shaped tip.

7. The tip structure of the long-term hemodialysis catheter according to claim 6, characterized in that, The symmetrical double S-shaped tip is symmetrically arranged relative to the baffle. The distance between the vertex of the S-side of the symmetrical double S-shaped tip and the starting end of the baffle is 3mm-9mm, and the distance between the low point of the S-side of the symmetrical double S-shaped tip and the starting end of the baffle is 6mm-18mm.

8. The long-term hemodialysis catheter tip structure of claim 5, wherein, In the double S-shaped tip structure, the distance between the vertex of the S-side of the double S-shaped tip corresponding to the vein cavity (3) and the starting end of the baffle is 3mm-9mm, and the distance between the low point of the S-side of the double S-shaped tip corresponding to the vein cavity (3) and the starting end of the baffle is 6mm-18mm; the distance between the vertex of the S-side of the double S-shaped tip corresponding to the arterial cavity (2) and the starting end of the baffle is 14mm-18.5mm, and the distance between the low point of the S-side of the double S-shaped tip corresponding to the arterial cavity (2) and the starting end of the baffle is 18mm-24mm.

9. The long-term hemodialysis catheter tip structure of claim 1, wherein, The port edge of the tip structure of the long-term hemodialysis catheter is rounded to form a smooth transition.

10. The long-term hemodialysis catheter tip structure of claim 1, wherein, It also includes a polyester sleeve (4), a catheter seat (5), a catheter seat connector (6), a catheter clamp (7), an arterial cavity extension tube (8), a venous cavity extension tube (9), and a Luer connector (10). The polyester sleeve (4) is sleeved on the outside of the tube body (1). The end of the tube body (1) away from the C / D-shaped tip or S-shaped tip is integrally formed with the catheter seat (5). The catheter seat connector (6) is connected to the catheter seat (5). The arterial cavity extension tube (8) is connected to the arterial cavity (2) through the catheter seat connector (6). The venous cavity extension tube (9) is connected to the venous cavity (3) through the catheter seat connector (6). The catheter clamp (7) and the Luer connector (10) are respectively arranged on the arterial cavity extension tube (8) and the venous cavity extension tube (9). The Luer connector (10) is located at the end of the arterial cavity extension tube (8) and the venous cavity extension tube (9).

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