CN116099101A

CN116099101A - Medical catheter

Info

Publication number: CN116099101A
Application number: CN202310383331.7A
Authority: CN
Inventors: 王磊; 吕纬岩; 张超; 杨尚; 澹台楚娟; 黄春磊
Original assignee: Beijing Jiushi Shenkang Medical Technology Co ltd
Current assignee: Beijing Jiushi Shenkang Medical Technology Co ltd
Priority date: 2023-04-12
Filing date: 2023-04-12
Publication date: 2023-05-12

Abstract

The invention relates to a medical catheter, which sequentially comprises a catheter seat, a stress release piece, a hypotube and a composite tube body from a proximal end to a distal end; the distal end of the hypotube is inserted into the composite tube body, and the proximal end of the hypotube is connected with the catheter seat; the hypotube has a through cavity of the same diameter from the proximal end to the distal end, and the hypotube has a proximal outer diameter that is greater than the distal outer diameter. When the invention is matched with a long sheath or a guiding catheter, the cavity at the superposition position of the long sheath or the guiding catheter is larger, so that larger suction force and catheter flow can be provided, and the near end can provide larger supporting performance.

Description

Medical catheter

Technical Field

The invention relates to the field of medical instruments, in particular to a medical catheter for vascular interventional therapy.

Background

In the treatment of stroke, the catheter-like device for interventional therapy needs to be as close to the vascular access of the lesion site as possible, so that the subsequent thrombus removing device or other therapeutic devices can reach the lesion site rapidly for corresponding treatment. In general, the distal end of the vascular access device needs to be compliant to pass through tortuous vessels, while the proximal end needs to be relatively stiff to provide a strong support for the subsequent device to ensure that it is in place successfully. While most vascular access devices are sufficiently flexible at the distal end, the proximal end does not provide adequate support; or the proximal end may provide sufficient support that the distal end is too stiff to be successfully placed in position through tortuous vessels. Meanwhile, due to the limitation of the size of the inner cavity of the catheter, when the catheter is combined with the thrombus taking device for thrombus taking, the catheter usually needs to be subjected to negative pressure suction, and the larger suction force becomes the key of successful thrombus taking. It is therefore necessary to design a distal access catheter with a distal end that is flexible enough to be in place successfully, a proximal end that is rigid enough to provide strong support, and a large suction force.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a medical catheter aiming at the defects.

The invention is realized by the following technical scheme:

a medical catheter, which comprises a catheter seat, a stress release piece, a hypotube and a composite tube body from a proximal end to a distal end in sequence; the distal end of the hypotube is inserted into the composite tube body, and the proximal end of the hypotube is connected with the catheter seat; the hypotube has a through cavity of the same diameter from the proximal end to the distal end, and the hypotube has a proximal outer diameter that is greater than the distal outer diameter.

Further, the composite tube body is of a cavity structure and comprises a lubricating inner layer, a middle reinforcing layer and an elastic outer layer from inside to outside in the radial direction; the elastic outer layer is processed outside the middle reinforcing layer by adopting a hot compress process.

Further, according to the medical catheter, the elastic outer layer is of a segmented structure, adjacent sections are connected in a thermal butt joint mode, and the Shore hardness difference of the adjacent sections is not more than 20D.

Further, in the medical catheter, the lubricating inner layer is made of PTFE or HDPE.

Further, the medical catheter is characterized in that the middle reinforcing layer is formed by braiding at least one super-elastic metal wire with shape memory.

Further, in the medical catheter, the elastic outer layer is made of at least one of polyamide, polyether amide and polyurethane, and a developing material is added.

Further, in the medical catheter, the proximal end and the distal end of the composite catheter body are respectively provided with a developing mark which does not project light, and the developing marks are in an open loop or closed loop structure and are embedded between the elastic outer layer and the middle reinforcing layer.

Further, in the medical catheter, a hydrophilic coating is further arranged outside the elastic outer layer of the composite catheter body.

Further, in the medical catheter, the outer diameter of the distal end of the hypotube is smaller than the inner diameter of the composite tube body, and the outer wall of the distal end of the hypotube is tightly attached to the inner wall of the composite tube body; the proximal end of the composite tube body is open and smoothly and gradually transitions to the hypotube.

Further, in the medical catheter, the proximal end of the composite tube body is transited to the hypotube through a connecting arc member.

The invention has the advantages and effects that:

1. the medical catheter provided by the invention has the advantages that the outer diameter of the proximal end of the hypotube is larger than the outer diameter of the distal end, and the distal end of the hypotube is inserted into the composite catheter body, so that when the hypotube is matched with a long sheath or a guiding catheter for use, the cavity at the position overlapping with the long sheath or the guiding catheter is larger, larger suction force and catheter flow can be provided, and the proximal end can provide larger supporting performance;

2. the medical catheter provided by the invention combines the composite tube body with soft distal end and the proximal end rigid hypotube, so that the medical catheter can provide soft distal end to potential energy and stronger proximal end supporting capability when passing through a tortuous blood vessel.

Drawings

FIG. 1 shows a schematic structural view of a medical catheter provided by the invention;

FIG. 2 shows a schematic structural view of a composite body of a medical catheter provided by the invention;

FIG. 3 is a schematic view showing the connection mode of a hypotube and a composite tube body of the medical catheter provided by the invention;

FIG. 4 shows a schematic view of the structure of a hypotube of a medical catheter provided by the present invention;

FIG. 5 shows a schematic structural view of a connecting arc member of a medical catheter provided by the present invention;

FIG. 6 is a schematic view showing the use state of the medical catheter according to the present invention;

fig. 7 shows a cross-sectional view A-A in fig. 6.

Reference numerals illustrate: 1-a catheter holder; 2-stress relief; 3-hypotubes; 31-the distal end of the hypotube; a proximal end of the 32-hypotube; 33-cutting grooves; 41-first developing marks; 42-a second development mark; 5-a composite pipe body; 6-a lubricating inner layer; 7-an intermediate reinforcing layer; 8-an elastic outer layer; 9-connecting the arc members; 10-the joint of the composite pipe body and the connecting arc part; 11-long sheath or guide catheter; a cavity between the 12-hypotube and the long sheath or guide catheter.

Detailed Description

In order to make the purposes, technical solutions and advantages of the implementation of the present invention more clear, the technical solutions in the embodiments of the present invention are described in more detail below with reference to the accompanying drawings in the embodiments of the present invention. The described embodiments are some, but not all, embodiments of the invention. The embodiments described below by referring to the drawings are illustrative and intended to explain the present invention and should not be construed as limiting the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention. Embodiments of the present invention will be described in detail below with reference to the attached drawings:

in the description of the present invention, it is to be understood that, unless otherwise indicated, the meaning of "a plurality" is two or more; the terms "center," "longitudinal," "transverse," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used for convenience in describing and simplifying the description based on the orientation or positional relationship shown in the drawings, and do not denote or imply that the devices or elements being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the scope of the invention. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention can be understood as appropriate by those of ordinary skill in the art.

In this specification, the term "proximal" generally refers to an end that is proximal to the operator of the medical device, and "distal" generally refers to an end that is distal from the operator of the medical device, typically the end that enters the human body first. As is well known to those skilled in the art, "Shore hardness" refers to a reading of a value measured with a Shore durometer in degrees (D). PPI is the unit of pixel density, which in the invention represents the number of cross-woven meshes per inch. PTFE is polytetrafluoroethylene (Poly tetra fluoroethylene, abbreviated as PTFE) and is a polymer obtained by polymerizing tetrafluoroethylene as a monomer. HDPE is a high density polyethylene.

Fig. 1 shows a schematic structural view of a medical catheter provided by the invention. The medical catheter comprises a catheter seat 1, a stress release part 2, a hypotube 3 and a composite tube body 5 from the proximal end to the distal end. The distal end of the hypotube 3 is inserted into the composite tube body 5, and the proximal end of the hypotube 3 is connected with the catheter seat 1. Specifically, the hypotube 3 is connected to the catheter hub 1 by integral injection molding, easily-setting glue, or other forms, and the strain relief 2 is secured to the exterior of the hypotube 3 and catheter hub 1 by physical snapping, heat shrinking, or other forms. As shown in figure 4, the hypotube 3 has a through cavity with the same diameter from the proximal end to the distal end, which provides a passageway for the passage of other instruments, and the proximal outer diameter of the hypotube 3 is larger than the distal outer diameter, allowing the proximal end to provide greater support. Specifically, the hypotube 3 is tapered with a smooth transition from the proximal end to the distal end. As shown in fig. 6 and 7, the distal end of the hypotube 3 is inserted into the composite tube body 5, and the proximal outer diameter of the hypotube 3 is larger than the distal outer diameter, so that when the medical catheter is matched with the long sheath or guide catheter 11, the cavity 12 between the hypotube 3 and the long sheath or guide catheter 11 is larger, and larger suction force and catheter flow can be provided. The outer layer of the hypotube is coated with a hydrophobic coating (not shown) that does not slide easily while providing support. The composite tube body 5 provides a flexible portion for the distal end portion of the medical catheter that can be passed infinitely near the lesion through tortuous vessels during the instrument placement. The joint section of the composite pipe body 5 and the hypotube 3 is in smooth transition. The hypotube 3 is the proximal portion of the medical catheter, which provides a rigid portion for strong support.

Fig. 2 shows a schematic structural view of a composite tube body of a medical catheter provided by the invention. The composite pipe body 5 is of a cavity structure and comprises a lubricating inner layer 6, a middle reinforcing layer 7 and an elastic outer layer 8 from inside to outside in the radial direction. The lubricating inner layer 6 is made of PTFE, HDPE or other materials with lubricating property, and is used for improving the lubricity of an inner cavity of the lubricating inner layer, reducing friction force when other instruments pass through and facilitating pushing of the other therapeutic instruments. The intermediate reinforcing layer 7 is braided from at least one superelastic wire with shape memory, the braiding density being between 60 and 150 PPI. Superelastic metals with shape memory include, but are not limited to, 304 stainless steel, nitinol, and the like. The elastic outer layer 8 is made of at least one of polyamide, polyether amide and polyurethane, and is added with a developing material, so that a doctor can see the shape of the whole catheter under X-ray. The elastic outer layer 8 is of a sectional structure, and can be specifically divided into at least five sections, and adjacent sections are connected in a thermal butt joint mode, wherein the Shore hardness difference of the adjacent sections is not more than 20D. The elastic outer layer 8 is processed outside the middle reinforcing layer 7 by adopting a hot compress process. The elastic outer layer 8 of the composite tube body 5 is also provided with a hydrophilic coating (not shown in the figure), so that the surface lubricity of the catheter can be remarkably improved, and the catheter can be smoother in a blood vessel. The composite tube body has various specifications, the diameter is between 0.5 and 2mm, the length is between 20 and 60cm, and the composite tube body can be adapted to blood vessels with different diameters and lengths.

As shown in fig. 1 and 2, the proximal end and the distal end of the composite tube body 5 are respectively provided with a developing mark which does not project light, and the developing mark is in an open loop or closed loop structure and is embedded between the elastic outer layer 8 and the middle reinforcing layer 7. Specifically, the inner wall of the developed mark is closely attached to the intermediate reinforcing layer 7, and the outer surface thereof is covered with the elastic outer layer 8. Located at the proximal end of the composite tube 5 is a first visualization mark 41 for clearly identifying the location as a junction with the hypotube under X-rays for corresponding manipulation by other instruments passing there through. Located at the distal end of the composite tubular body 5 is a second visualization marker 42 for allowing the physician to accurately deliver the catheter to the designated location of the vessel under X-rays.

Fig. 3 shows a schematic diagram of a connection mode between a hypotube and a composite tube body of a medical catheter provided by the invention. The outer diameter of the distal end of the hypotube 3 is smaller than the inner diameter of the composite tube body 5, and the distal end of the hypotube 3 is inserted into the composite tube body 5, so that when the medical catheter is matched with the long sheath or guide catheter 11 for use, the cavity 12 between the hypotube 3 and the long sheath or guide catheter 11 is larger, and larger suction force and catheter flow can be provided. The outer wall of the distal end of the hypotube 3 is arranged closely to the inner wall of the composite tube body 5. The proximal end of the composite tubular body 5 is open and smoothly and gradually transitions to the hypotube 3, the transition portion being wrapped with the same material as the elastic outer layer 8. Specifically, as shown in fig. 5, the proximal end of the composite tube body 5 is transited to the hypotube 3 by a connecting arc member 9, and the connecting arc member 9 may be in a fan-shaped sheet or a woven mesh structure. As shown in fig. 3, the large arc-shaped end of the sector of the connecting arc part 9 is connected to the composite pipe body 5 at the connection 10 of the composite pipe body and the connecting arc part, and the small arc-shaped end of the sector is connected to the hypotube 3. The connecting arc member 9 is preferably, but not limited to, made of polyamide, polyether amide, polyurethane, etc. Alternatively, a portion of the proximal end of the elastomeric outer layer 8 of the composite tubular body 5 extends outwardly and gradually retracts to fan-connect to the hypotube 3. As shown in fig. 2, a cut groove 33 is provided on the inner wall of the composite pipe body 5 at the contact point with the distal end of the hypotube 3 in order to better thermally weld the composite pipe body 5 with the hypotube 3.

The above embodiments are only for illustrating the technical solution of the present invention, and are not intended to limit the implementation scope of the present invention. All equivalent changes and modifications within the scope of the present invention should be considered as falling within the scope of the present invention.

Claims

1. A medical catheter, which comprises a catheter seat (1), a stress release piece (2), a hypotube (3) and a composite tube body (5) from the proximal end to the distal end in sequence; the device is characterized in that the distal end of the hypotube (3) is inserted into the composite tube body (5), and the proximal end of the hypotube (3) is connected with the catheter seat (1); the hypotube (3) has a through cavity of the same diameter from proximal to distal end, and the hypotube (3) has a proximal outer diameter that is greater than a distal outer diameter.

2. A medical catheter according to claim 1, characterized in that the composite tubular body (5) is of a hollow structure comprising, from inside to outside in the radial direction, a lubricating inner layer (6), an intermediate reinforcing layer (7) and an elastic outer layer (8); the elastic outer layer (8) is processed outside the middle reinforcing layer (7) by adopting a hot compress process.

3. A medical catheter according to claim 2, wherein the elastic outer layer (8) is of a segmented construction and adjacent segments are connected by thermal butt joint, the shore hardness difference of the adjacent segments being not more than 20D.

4. A medical catheter according to claim 2 or 3, characterized in that the lubricious inner layer (6) is of PTFE or HDPE material.

5. A medical catheter according to claim 2 or 3, characterized in that the intermediate reinforcement layer (7) is braided from at least one superelastic wire with shape memory.

6. A medical catheter according to claim 2 or 3, characterized in that the elastic outer layer (8) is made of at least one of polyamide, polyether amide and polyurethane, with the addition of a developing material.

7. A medical catheter according to claim 2 or 3, characterized in that the proximal and distal ends of the composite tube body (5) are provided with respective light-non-projecting development marks, which are of open-loop or closed-loop construction, embedded between the elastic outer layer (8) and the intermediate reinforcing layer (7).

8. A medical catheter according to claim 2 or 3, characterized in that the elastic outer layer (8) of the composite tube body (5) is provided with a hydrophilic coating.

9. A medical catheter according to any of claims 1 to 3, characterized in that the outer diameter of the distal end of the hypotube (3) is smaller than the inner diameter of the composite tube body (5), the outer wall of the distal end of the hypotube (3) being arranged against the inner wall of the composite tube body (5); the proximal end of the composite tube body (5) is open and smoothly and gradually transits to the hypotube (3).

10. A medical catheter according to claim 9, characterized in that the proximal end of the composite tube body (5) is transited to the hypotube (3) by means of a connecting arc member (9).