CN-121987879-A - Indwelling needle catheter with turbulence resistance and backflow resistance for hemodialysis

CN121987879ACN 121987879 ACN121987879 ACN 121987879ACN-121987879-A

Abstract

The invention discloses a detaining needle catheter with turbulence resistance and backflow resistance for hemodialysis, which belongs to the technical field of medical instruments, and comprises a catheter main body made of biocompatible materials, wherein the inside of the catheter main body is divided into an independent blood output channel and an independent blood input channel, two axially staggered hydrodynamic optimized side hole areas are arranged at the far-end implantation section of the catheter and are respectively used as a blood inlet and a blood outlet of the two channels, wherein the inlet area is positioned at the far end, the outlet area is positioned at the rear of the near end of the catheter main body, and unidirectional valve clack type backflow prevention devices are integrally arranged in the inside of each channel and behind the near end of the corresponding side hole area.

Inventors

LEI BING
CHEN HAO
HU GANG

Assignees

四川普瑞斯生物科技有限公司

Dates

Publication Date: 20260508
Application Date: 20260318

Claims (8)

1. The indwelling needle catheter for hemodialysis with turbulence resistance and backflow resistance functions is characterized by comprising a catheter main body, wherein an integrally formed separation membrane penetrating through the whole length of the catheter to a distal end is axially arranged in the catheter main body, and the separation membrane separates the interior of the catheter main body into a blood output channel and a blood input channel which are mutually independent; The cross sections of the blood output channel and the blood input channel are in a fit type asymmetric D shape, straight edges of the two channels are in seamless fit through the separation membrane, the separation membrane and the catheter main body are of an integrated structure made of the same material, and a fillet of the D-shaped cross section is in smooth arc transition without sharp edges; the proximal ends of the blood output channel and the blood input channel respectively extend out of an interface end for connecting an extracorporeal pipeline; the distal implantation section of the catheter body is provided with a first side hole area and a second side hole area which are staggered with each other in the axial direction: The first side hole area is formed by a plurality of side holes penetrating through the wall of the blood output channel and is used as a blood inlet of the blood output channel, and the first side hole area is positioned at the most distal end of the catheter; The second side hole area is formed by a plurality of side holes penetrating through the wall of the blood input channel and is used as a blood outlet of the blood input channel, and the second side hole area is positioned behind the proximal end of the first side hole area; A first backflow preventing device is integrally arranged in the blood output channel at a straight section of the tube cavity behind the edge of the proximal end of the first side hole area, the first backflow preventing device is an cantilever type elastic valve, a fixed end of the first backflow preventing device is integrally connected with the inner wall of the blood output channel, the fixed end is positioned at one side close to the first side hole area, and a free end of the first backflow preventing device extends towards the proximal direction of the tube; A second backflow preventing device is integrally arranged in the blood input channel at a straight section of the tube cavity behind the edge of the proximal end of the second side hole area, the second backflow preventing device is an cantilever type elastic valve, a fixed end of the second backflow preventing device is integrally connected with the inner wall of the blood input channel, the fixed end is positioned at one side close to the proximal end of the catheter, and a free end of the second backflow preventing device extends towards the direction of the second side hole area; The inner wall of the pipe cavity at the downstream of the first backflow preventing device and the second backflow preventing device is provided with an integrally formed annular step valve seat, the joint surface of the annular step valve seat is an arc concave surface matched with the free end of the corresponding valve clack, and the free end of the valve clack is elastically abutted to the arc concave surface in a normal state and is in seamless joint with the arc concave surface to form a surface sealing structure.
2. The indwelling needle catheter with turbulence resisting and backflow preventing functions for hemodialysis according to claim 1, wherein the side holes of the first side hole area and the second side hole area are a plurality of rows of side holes which are arranged in a staggered mode in the circumferential direction, the side holes of the same axial position are staggered in the circumferential direction, and the adjacent rows of side holes are distributed in a staggered mode in the axial direction; The distal end of the first side hole area is flush with the distal end face of the catheter main body, the distal end face of the catheter is provided with an arc chamfer, and the chamfer face and the outer wall of the catheter form a smooth face.
3. The indwelling needle catheter with turbulence resisting and backflow preventing functions for hemodialysis according to claim 1, wherein the roots of the cantilever beam type elastic valve of the first backflow preventing device and the second backflow preventing device are provided with reinforced cambered surface transition structures, the cantilever beam type elastic valve body is in a sheet shape, the back surface of the free end of the cantilever beam type elastic valve body is provided with the cambered surface, the annular step valve seat is a circumferential continuous convex ring, the cross section of the convex ring is arc-shaped or triangular, the convex ring and the cambered surface of the free end of the cantilever beam type elastic valve form line contact or surface contact sealing, and the cambered surface roughness of the valve seat is lower than that of the cantilever beam type elastic valve body.
4. The indwelling needle catheter with turbulence resisting and backflow preventing functions for hemodialysis according to claim 1, wherein the first backflow preventing device and the second backflow preventing device are one of an cantilever beam type elastic valve, a duckbill valve or a pressure setting valve, the fixed end of the cantilever beam type elastic valve is a widened annular base, the base is integrally adhered or embedded with the inner wall of a lumen, two symmetrical arc-shaped elastic folds are arranged on the main body of the valve, the folds are arranged along the blood flow direction, a thickened arc lip is arranged at the valve port of the duckbill valve, the lip is in a water drop shape in cross section, the lips at two sides are tightly attached in a non-pressure state, the valve core of the pressure setting valve is in a hollow elastic ball structure, the thickness of the ball wall is in gradient change, and the thickness of the proximal side wall is larger than that of the distal side wall.
5. The indwelling needle catheter with turbulence and reflux resisting functions for hemodialysis according to claim 4, wherein the cantilever type elastic valve is of a double-layer composite structure, the inner layer is a high-elasticity core layer, the outer layer is a low-friction wear-resistant layer, the two layers are connected in a seamless mode through molecular bonding, the free end edge of the valve is subjected to thinning circular arc treatment, the thickness of a thinned area is one third to one half of the thickness of a valve main body, the double-layer composite structure extends to the widened annular substrate, and the outer layer of the substrate area is thickened to form a reinforcing ring.
6. The indwelling needle catheter with turbulence resistance and backflow prevention functions for hemodialysis according to claim 5, wherein at least one independent additional function cavity is formed in the catheter main body, the additional function cavity penetrates through the whole length of the catheter main body, the cross section of the additional function cavity is crescent-shaped, oval-shaped or triangular, the additional function cavity is attached to the outer edge outline of the blood output channel or the blood input channel, a distal opening of the additional function cavity is arranged beside an arc chamfer of the most distal end of the catheter, an independent interface end extends out of the proximal end of the additional function cavity, the additional function cavity is completely isolated from the blood output channel and the blood input channel through the separation membrane or the independent membrane, one or more grooves are formed in the inner wall of the lumen of the additional function cavity in the axial direction, flexible sensing wires are embedded in the grooves, the surface of the sensing wires is flush with the inner wall of the lumen, and a proximal interface of the additional function cavity is of a multi-way structure and can be used for simultaneously connecting at least two of an injector, a pressure sensor and an infusion tube.
7. The indwelling needle catheter with turbulence resisting and backflow preventing functions for hemodialysis according to claim 6, wherein a separation rib is arranged in the additional functional cavity along the axial direction and divides the additional functional cavity into a plurality of subchambers, the proximal end of each subchamber is respectively provided with an independent interface, the distal end of each subchamber is respectively provided with an independent opening, and the openings of each subchamber are mutually staggered in the axial direction or are positioned at the same axial position but are staggered in the circumferential direction; The miniature one-way valve film is integrated at the far-end opening of the additional function cavity, the one-way valve film is of a slit type self-sealing structure, is kept in a closed state when no external force is injected, is elastically opened under the action of injection pressure, is integrally formed with the inner wall of the additional function cavity or is connected with the inner wall of the additional function cavity through secondary injection molding, and is used for injecting medicine, measuring pressure, taking blood or implanting a sensor.
8. The indwelling needle catheter with turbulence resistance and backflow resistance for hemodialysis according to any one of claims 1 to 7, wherein the walls of the first side hole area and the second side hole area are of double-layer thickened structures, the inner layer is a base layer made of the same material as the catheter body, the outer layer is a high-elasticity wear-resistant layer, radial reinforcing ribs are arranged between the two layers, and the reinforcing ribs are uniformly distributed along the circumference of the side hole and are in seamless connection with the side hole wall; The side holes penetrate through the double-layer pipe wall, and the hole wall is subjected to smooth polishing treatment without burrs.

Description

Indwelling needle catheter with turbulence resistance and backflow resistance for hemodialysis Technical Field The invention belongs to the technical field of medical appliances, and particularly relates to an indwelling needle catheter with turbulence resistance and backflow resistance for hemodialysis. Background Hemodialysis is a critical treatment for life support in end stage renal patients and relies on a stable, efficient extracorporeal blood circulation pathway. Central venous indwelling catheters have become one of the important vascular access types because of their ability to rapidly establish large flow pathways, particularly for patients who are unable to establish autologous arteriovenous fistulae. Hemodialysis catheters widely used in clinic at present generally adopt a double-cavity or multi-cavity structure to achieve the leading-out and feedback of blood, however, the catheters still face a plurality of key technical challenges in long-term use, and influence the safety and efficiency of treatment, namely turbulent flow, vortex flow and local high shear force are easy to generate when blood flows through the openings at high speed. This undesirable flow pattern not only increases blood flow resistance, but also causes mechanical damage to blood cells, and activates platelets and clotting factors, significantly exacerbating the risk of thrombus formation within the catheter. Thrombosis can further reduce blood flow, affect dialysis adequacy, and may even cause serious complications such as thromboembolism. At present, most catheters do not have an active backflow prevention mechanism, and the prevention of the backflow of blood in the intermittent period of treatment or the cross contamination of blood and dialysate in treatment mainly depends on the correct use of an external clamping device, heparin cap sealing pipes and strict adherence to operation rules of medical staff. This approach is passive in nature and relies on manual manipulation, which, once inadvertent or malfunctioning of the external device, may lead to blood reflux, air ingress, or reverse flow of dialysate into the blood, thereby posing serious medical risks of infection, air embolism, and thrombosis. Disclosure of Invention The invention aims to provide an indwelling needle catheter for hemodialysis with turbulence resistance and backflow resistance, which can be realized by the following technical scheme: The indwelling needle catheter for hemodialysis with turbulence resistance and backflow resistance functions is characterized by comprising a catheter main body, wherein an integrally formed separation membrane penetrating through the whole length of the catheter to a distal end is axially arranged in the catheter main body, and the separation membrane separates the interior of the catheter main body into a blood output channel and a blood input channel which are mutually independent; The cross sections of the blood output channel and the blood input channel are in a fit type asymmetric D shape, straight edges of the two channels are in seamless fit through the separation membrane, the separation membrane and the catheter main body are of an integrated structure made of the same material, and a fillet of the D-shaped cross section is in smooth arc transition without sharp edges; the proximal ends of the blood output channel and the blood input channel respectively extend out of an interface end for connecting an extracorporeal pipeline; the distal implantation section of the catheter body is provided with a first side hole area and a second side hole area which are staggered with each other in the axial direction: The first side hole area is formed by a plurality of side holes penetrating through the wall of the blood output channel and is used as a blood inlet of the blood output channel, and the first side hole area is positioned at the most distal end of the catheter; The second side hole area is formed by a plurality of side holes penetrating through the wall of the blood input channel and is used as a blood outlet of the blood input channel, and the second side hole area is positioned behind the proximal end of the first side hole area; A first backflow preventing device is integrally arranged in the blood output channel at a straight section of the tube cavity behind the edge of the proximal end of the first side hole area, the first backflow preventing device is an cantilever type elastic valve, a fixed end of the first backflow preventing device is integrally connected with the inner wall of the blood output channel, the fixed end is positioned at one side close to the first side hole area, and a free end of the first backflow preventing device extends towards the proximal direction of the tube; A second backflow preventing device is integrally arranged in the blood input channel at a straight section of the tube cavity behind the edge of the proximal end of the second side hole area, the second backflow preve