CN113827842A

CN113827842A - Medical catheter and preparation method thereof

Info

Publication number: CN113827842A
Application number: CN202111427473.6A
Authority: CN
Inventors: 高洪亮; 吕怡然; 梁栋; 周连海
Original assignee: Aike Medical Devices Beijing Co ltd
Current assignee: Eco Medical Devices Beijing Co ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2021-12-24
Anticipated expiration: 2041-11-29
Also published as: CN113827842B

Abstract

The application discloses medical catheter, it includes the body, toper buffer tube and tube socket, the body is connected to in the toper portion of tube socket, toper buffer tube cup joints at body near-end and tube socket toper portion outside, the body include the body straight tube and with body straight tube smooth connection's body near-end horn mouth, form the clearance between the straight tube of body and tube socket inner chamber distal end horn mouth and the thin waist of tube socket inner chamber, body near-end horn mouth supports to lean on tube socket inner chamber near-end horn mouth, the constraint pipe inserts in the body near-end horn mouth. A method for preparing a medical catheter, the far end of the tube body penetrates into the near end of the tube seat and penetrates out of the far end of the tube seat until the near end bell mouth of the tube body enters the near end bell mouth of the inner cavity of the tube seat and enables the tube body and the tube seat to form loose fit and enables a conical buffer tube to be sleeved at the near end of the tube body and outside the conical part of the tube seat. The catheter and the preparation method have the advantages that: the self-expanding stent can smoothly enter the catheter body through the binding tube, and prevents catheter falling objects from entering blood vessels of a human body to cause medical accidents.

Description

Medical catheter and preparation method thereof

Technical Field

The application relates to the field of medical instruments, in particular to a medical catheter and a preparation method thereof.

Background

Intravascular devices such as catheters are often used in the medical field. Catheters are typically inserted into the femoral artery, radial artery, carotid artery, or jugular vein of a patient and are navigated through the patient's blood vessels to the heart, brain, or other target anatomy. Typically, a guidewire is first guided to the target anatomy, and one or more catheters are then passed over the guidewire and guided to the target anatomy. Once in place, the catheter may be used to deliver drugs, stents, embolic devices, radiopaque dyes, or other devices or substances for treating the patient in a desired manner. In other cases, the catheter and guidewire are delivered simultaneously toward the target anatomy while the guidewire is within the catheter, and then the guidewire is further delivered into the anatomy by translation within the catheter.

In many applications, the catheter needs to travel through a tortuous vessel to an anatomical site, which requires that the intravascular catheter have good pressure resistance, strong torque, pushability, strong resistance to bending, and timely responsiveness. One type of medical catheter of the prior art includes a tube body, a tapered buffer tube and a hub, wherein the tube body is inscribed within the tapered portion of the hub and the tapered buffer tube is sleeved at the proximal end of the tube body and outside the tapered portion of the hub. The tapered buffer tube helps to prevent the catheter from bending at the junction of the tube body and the tube base during use. The pipe body and the pipe seat are fixed together in an adhesive mode. The conical buffer tube is fixed with the tube seat in an interference fit or bonding mode.

Self-expanding stents are typically crimped in a crimp tube, which is fitted with a hub leading into the catheter. Due to the limitation of the matching use of each interventional instrument and the design characteristics of each instrument, when the binding tube is matched with the tube seat, the head end of the binding tube cannot directly reach the proximal end of the tube body of the catheter, and the proximal end of the tube body is not in seamless connection with the tube seat in bonding matching. This has just led to tying the tube head end and body near-end to have a certain distance, and when the support stretches out and gets into the body straight tube through this section distance from tying the tube head end, need pass through the cooperation position of body and tube socket, the cooperation of body and tube socket has interval or gap, and this will lead to expanding the support certainly and can't get into the body straight tube. If the bracket enters the straight pipe of the pipe body by adopting strong force, the head end of the bracket can be damaged. The stent with unknown damage is dangerous to enter the catheter, and the inner wall of the catheter is possibly damaged and damaged, so that the fallen object of the catheter enters the blood vessel of a human body, and medical accidents are caused.

Self-expanding stents are typically crimped in a crimp tube, which is fitted with a hub leading into the catheter. The cooperation mode between body and the tube socket for at the in-process of viscose, glue can flow out the fitting surface of body and tube socket through the gap, permeates in the tube socket, overflows even in the body, causes the unable body straight tube that gets into of apparatus. The wall thickness of pipe and the step type design of tube socket cooperation department for when pipe and tube socket bond, the dislocation appears very easily, the design of pipe, when guaranteeing the performance of pipe, the pipe wall is thinner, and the body external diameter is littleer, and the official cavity is bigger, and then the pipe performance is better, and this is very high to the tolerance and the machining precision requirement of the cooperation department of pipe body and tube socket. A certain gap is needed between the tube seat and the tube body for filling glue. The glue that is commonly used is a UV-curable glue, which has a flow property. In the bonding process, glue enters from the far end of the tube seat, when the glue is about to penetrate into the matching part of the end face of the near end of the tube body and the tube seat, the UV lamp needs to be turned on as soon as possible, and the glue can penetrate through the matching part of the end face often because of the process, so that the product is poor. In order to avoid the glue from penetrating through the end face matching part, a certain force is often applied to ensure that the end face parts of the pipe body and the pipe seat are tightly matched, so that the glue is prevented from penetrating. Therefore, the gas between the pipe body and the pipe seat can not be discharged in the dispensing process, and the glue can not leak to the root parts of the pipe body and the pipe seat.

The application aims to provide a novel medical catheter and a preparation method thereof, and solves the problems in the prior art, so that a self-expanding type support can smoothly enter a straight pipe of a catheter body through a binding pipe, the falling object of the catheter is prevented from entering a human blood vessel under the action of external force, medical accidents are caused, gas can be discharged in the dispensing process due to loose matching of the catheter body and a tube seat, and the tube seat and the catheter body are easy to combine.

Disclosure of Invention

The present application is directed to a novel medical catheter and a method for manufacturing the same to solve the problems of the prior art. The object of the present invention is achieved by the following means.

An embodiment of the application provides a medical catheter, medical catheter includes the body, toper buffer tube and tube socket, the body is connected to in the toper portion of tube socket, toper buffer tube cup joints at body near-end and tube socket toper portion outside, the tube socket includes the toper connecting portion, tube socket main part and the tube socket inner chamber of setting in the tube socket, the tube socket inner chamber includes tube socket inner chamber distal end horn mouth, the thin waist of tube socket inner chamber and tube socket inner chamber proximal end horn mouth, the body include the body straight tube and with body straight tube smooth connection's body proximal end horn mouth, form the clearance between body straight tube and tube socket inner chamber distal end horn mouth and the thin waist of tube socket inner chamber, body proximal end horn mouth supports and leans on tube socket inner chamber proximal end horn mouth, the constraint pipe inserts in the body proximal end horn mouth.

A medical catheter is provided according to one of the above embodiments of the present application wherein the angle a1 of the proximal flare of the tube body is equal to the angle a2 of the proximal flare of the lumen of the hub.

A medical catheter is provided according to one embodiment of the present application, wherein the outer diameter OD1 of the proximal flare of the catheter body, the outer diameter OD2 of the proximal non-variable diameter portion of the catheter body and the inner diameter ID of the proximal flare of the catheter body are in the following ranges: OD2+0.4mm < ID < OD1 <4mm, 0.6mm < external diameter OD4 of the restraint tube < internal diameter ID of the tube body near-end bell mouth < OD1 <4mm, and the external diameter OD2 at the non-reducing position of the tube body near end is in the following range: 0.5mm < OD2<4 mm.

A medical catheter is provided according to one of the above embodiments of the present application, wherein the relationship between the tube body proximal flare angle a1 and the length L of the tube body tapered section is defined by the following equation:

wherein OD1 is the outer diameter of the bell mouth at the near end of the tube body, and the outer diameter of the non-reducing part at the near end of the OD2 tube body.

According to the medical catheter provided by the embodiment of the application, the outer diameter OD2 at the non-reducing part of the proximal end of the tube body is less than the slender inner diameter OD3-0.2mm of the inner cavity of the tube seat.

A medical catheter is provided according to one embodiment of the present application, wherein the tube body has a proximal flare angle a1 in a range of: 6 DEG < A1 < 90 deg.

According to one embodiment of the present application, there is provided a medical catheter, wherein the included angle B of the horn at the distal end of the lumen of the hub is in the range of:

。

according to the medical catheter provided by the above one embodiment of the application, the distance D between the tube body and the inner wall of the port of the horn mouth at the far end of the inner cavity of the tube seat ranges from:

。

according to one embodiment of the present application, a medical catheter is provided, wherein the proximal flare of the catheter body is prepared by a conical chamfer.

A medical catheter is provided according to one of the above embodiments of the present application in which a tapered buffer tube may be connected by an interference fit over the proximal exterior of the hub and the tapered exterior of the hub.

Another embodiment of the present application provides a method of manufacturing a medical catheter, wherein the method of manufacturing includes the steps of:

step 1: sleeving the inner layer of the pipe body on a mandrel with the shape consistent with that of the pipe body;

step 2: stretching and knotting the inner layer of the pipe body;

and step 3: braiding a metal wire from the distal end of the catheter to form a metal braid;

and 4, step 4: forming a pipe body outer layer on the metal braided layer outer sleeve and fusing all layers of the pipe body together by heating;

and 5: the far end of the tube body penetrates into the near end of the tube seat and penetrates out of the far end of the tube seat until the near-end bell mouth of the tube body enters the near-end bell mouth of the inner cavity of the tube seat and the tube body and the tube seat form loose fit;

step 6: glue is dispensed to enable glue to gradually penetrate into the outer surface of the cone at the near end of the tube body, the tube body is drawn, the horn mouth at the near end of the tube body is attached to the horn mouth at the near end of the tube seat, and UV curing is carried out; and

and 7: after the pipe body and the pipe seat are assembled, the conical buffer part is sleeved on the pipe body and the pipe seat.

The medical catheter prepared by the preparation method has the advantages that the binding tube is directly inserted into the horn mouth at the near end of the tube seat, so that the bracket can directly enter the tube body through the binding tube and cannot be clamped in the matching area of the tube body and the tube seat.

The medical catheter prepared by the preparation method has the advantages that the horn mouth at the near end of the catheter body is prepared by the conical chamfer, so that the catheter body cannot puncture the inner wall of the catheter seat when being inserted into the inner cavity of the catheter seat from the near end of the catheter seat and penetrates out of the far end of the catheter seat, and falling objects are prevented from entering blood vessels of a human body.

The medical catheter prepared by the preparation method has the advantages that the tube body and the tube seat are in loose fit, so that air between the tube seat and the tube body can be discharged only from the lower end, glue flows along the tube body and is cured in time, and the glue cannot flow into the tube seat and the tube body.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, made with reference to the accompanying drawings.

Fig. 1 shows a cross-sectional view of a medical catheter of the prior art.

Figure 2 shows a cross-sectional view of a prior art hub of a medical catheter.

Fig. 3 illustrates a cross-sectional view of a tubular body of a medical catheter in accordance with one embodiment of the present application.

Fig. 4 illustrates a schematic tube installation of a medical catheter according to an embodiment of the present application.

FIG. 5 shows a schematic view of the lumen of a hub of a medical catheter mated with a tube body according to one embodiment of the present application.

FIG. 6 shows a schematic view of the mating of a hub taper and a tube body of a medical catheter according to one embodiment of the present application.

FIG. 7 illustrates a cross-sectional view of a medical catheter tube after assembly, according to one embodiment of the present application.

Fig. 8 shows a schematic view of a proximal flared cone chamfer of a body of a medical catheter according to an embodiment of the present application.

FIG. 9 illustrates a method of making a medical catheter in accordance with one embodiment of the present application.

FIG. 10 shows a schematic view of a tube inner layer and mandrel set of a medical catheter according to one embodiment of the present application.

FIG. 11 illustrates a schematic view of a tube intermediate layer of a medical catheter in accordance with one embodiment of the present application.

Reference numerals and parts lists

Detailed Description

The following description of the embodiments of the present application with reference to the drawings and examples will make it apparent to those skilled in the art that the technical problems, technical solutions and technical effects of the present application can be easily solved through the contents described in the present specification. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. In addition, for convenience of description, only portions related to the related invention are shown in the drawings.

It should be noted that the structures, proportions, sizes, and other elements shown in the drawings are only used for understanding and reading the contents of the specification, and are not used for limiting the conditions under which the present application can be implemented, so they do not have the technical significance, and any structural modifications, changes in proportion, or adjustments of sizes, which do not affect the efficacy and achievement of the purposes of the present application, shall still fall within the scope of the technical content disclosed in the present application.

Reference herein to words such as "first," "second," "the," and the like do not denote a limitation of quantity, but rather denote the singular or plural. The present application is directed to the terms "comprising," "including," "having," and any variations thereof, which are intended to cover non-exclusive inclusions; for example, a process, method, system, article, or apparatus that comprises a list of steps or modules (elements) is not limited to the listed steps or elements, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus. Reference to "connected," "coupled," and the like in this application is not intended to be limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

Reference herein to "a plurality" means greater than or equal to two. "and/or" describes an association relationship of associated objects, meaning that three relationships may exist, for example, "A and/or B" may mean: a exists alone, A and B exist simultaneously, and B exists alone. Reference herein to the terms "first," "second," "third," and the like, are merely to distinguish similar objects and do not denote a particular ordering for the objects.

Fig. 1 shows a cross-sectional view of a medical catheter of the prior art. Figure 2 shows a cross-sectional view of a prior art hub of a medical catheter. As shown in FIG. 1, a medical catheter 1 of the prior art includes a tubular body 10, a tapered buffer tube 11 and a hub 12, the tubular body 10 being connected to the hub 12 within a tapered connection 121, the tapered buffer tube 11 being sleeved at the proximal end 100 of the tubular body and outside the hub tapered connection 121. Figure 2 shows a cross-sectional view of a prior art hub of a medical catheter. As shown in fig. 2, a tube socket of a medical catheter in the prior art is manufactured by using the national standard GB1962.1, and includes a tapered connection portion 121, a tube socket main body 122, and a tube socket inner cavity 123 disposed in the tube socket, where the tube socket inner cavity 123 includes a tube socket inner cavity distal horn mouth 123a, a tube socket inner cavity thin waist 123b, and a tube socket inner cavity proximal horn mouth 123c, and the tube socket inner cavity thin waist 123b is used to connect the tube socket inner cavity distal horn mouth 123a and the tube socket inner cavity proximal horn mouth 123c together.

Fig. 3 illustrates a cross-sectional view of a tubular body of a medical catheter in accordance with one embodiment of the present application. The tube 10 includes a straight tube 101a and a tube proximal flare 101b smoothly connected to the straight tube 101 a. Fig. 4 illustrates a schematic tube installation of a medical catheter according to an embodiment of the present application. In an alternative embodiment, the tube proximal flare angle A1 and the hub lumen proximal flare angle A2 are equal.

In the medical catheter according to one embodiment of the present application, the outer diameter OD1 of the proximal flare of the catheter body, the outer diameter OD2 of the proximal non-variable diameter portion of the catheter body, and the inner diameter ID of the proximal flare of the catheter body are in the following ranges: OD2+0.4mm < ID < OD1 <4mm, 0.6mm < external diameter OD4 of the restraint tube < internal diameter ID of the tube body near-end bell mouth < OD1 <4mm, and the external diameter OD2 at the non-reducing position of the tube body near end is in the following range: 0.5mm < OD2<4 mm.

In a medical catheter according to an embodiment of the present application, the relationship between the tube proximal flare angle a1 and the length L of the tube tapered section is defined by the following equation:

OD1 is the outer diameter of the bell mouth at the near end of the tube body, and OD2 is the outer diameter of the non-reducing part at the near end of the tube body.

In the medical catheter according to one embodiment of the application, the outer diameter OD2 at the non-reducing part of the proximal end of the tube body is less than the inner diameter OD3-0.2mm <4mm of the slender waist of the inner cavity of the tube seat.

In a medical catheter according to an embodiment of the present application, the angle a1 of the flared proximal end of the catheter body ranges from: 6 DEG < A1 < 90 deg.

FIG. 5 shows a schematic view of the lumen of a hub of a medical catheter mated with a tube body according to one embodiment of the present application. In a medical catheter according to an embodiment of the present application, the included angle B of the flare at the distal end of the lumen of the hub ranges from:

。

in the medical catheter according to an embodiment of the present application, the distance D between the tube body 10 and the inner wall of the port of the bell mouth 123a at the distal end of the lumen of the tube holder ranges from:

。

fig. 4 illustrates a tube mounting of a medical catheter according to an embodiment of the present application. Fig. 8 illustrates an assembled partial cross-sectional view of a body of a medical catheter in accordance with an embodiment of the present application. In the medical catheter according to an embodiment of the present application, the straight tube 101a of the tube body 10 passes through the tube socket inner cavity, the tube body 10 passes through the tube socket distal outlet and makes the tube body proximal flare 101b abut against the tube socket inner cavity proximal flare 123c, the straight tube 101a extends from the tube socket inner cavity waistline 123b through the tube socket inner cavity distal flare 123a, and a gap 125 is formed between the straight tube 101a, the tube socket inner cavity distal flare 123a and the tube socket inner cavity waistline 123b, and glue can be injected into the gap 125 without flowing into the tube socket 12 and without entering the tube body 10. In the medical catheter according to one embodiment of the present application, the straight tether tube 13 is inserted into the tube proximal end bell mouth 101b of the tube body 10 so that the stent can smoothly enter the tube body from the tether tube 13. The bracket is not caught in the fitting region 103a of the tube body 10 and the stem.

In an alternative embodiment of the present application, the tapered buffer tube may be connected by an interference fit (see FIG. 1) over the proximal exterior of the tube socket and the tapered portion exterior of the tube socket. While some embodiments of the present application do not show a tapered buffer tube, those skilled in the art know from the prior art how to splice a tapered buffer tube into the proximal end of a tube body and out of the tapered portion of a tube holder to prepare a medical catheter.

Fig. 8 shows a schematic view of a proximal flared cone chamfer of a body of a medical catheter according to an embodiment of the present application. As shown in fig. 8, the tube body proximal end bell mouth 101b is manufactured by adopting a cone chamfer and adopting the national standard GB 1962.1. This is advantageous in preventing the damage to the inner wall of the tube seat when the tube body passes through the tube seat.

FIG. 9 illustrates a method of making a medical catheter in accordance with one embodiment of the present application. The preparation method comprises the following steps:

step 100: sleeving the inner layer of the pipe body on a mandrel with the shape consistent with that of the pipe body;

step 200: stretching and knotting the inner layer of the pipe body;

step 300: braiding a metal wire from the distal end of the catheter to form a metal braid;

step 400: forming a pipe body outer layer on the metal braided layer outer sleeve and fusing all layers of the pipe body together by heating;

step 500: the far end of the tube body penetrates into the near end of the tube seat and penetrates out of the far end of the tube seat until the near-end bell mouth of the tube body enters the near-end bell mouth of the inner cavity of the tube seat and the tube body and the tube seat form loose fit;

step 600: glue is dispensed to enable glue to gradually penetrate into the outer surface of the cone at the near end of the tube body, the tube body is drawn, the horn mouth at the near end of the tube body is attached to the horn mouth at the near end of the tube seat, and UV curing is carried out; and

step 700: after the pipe body and the pipe seat are assembled, the conical buffer part is sleeved on the pipe body and the pipe seat.

FIG. 10 shows a schematic view of a tube inner layer and mandrel set of a medical catheter according to one embodiment of the present application. FIG. 11 illustrates a schematic view of a tube intermediate layer of a medical catheter in accordance with one embodiment of the present application. As shown in fig. 10 and 11, the inner tube layer 1000 is fitted over the mandrel 15, and the mandrel 15 is ground to conform to the shape of the tube, with the taper angle of the mandrel tip being equal to the angle a1 of the tube proximal flare. According to the process requirement and the strength of the inner layer 1000 of the pipe body, the end of the mandrel can be subjected to smooth treatment, the inner layer of the pipe body is prevented from being poked through the mandrel 15, and the end of the mandrel can be subjected to arc-shaped treatment.

The inner pipe of the pipe body is penetrated on the mandrel. In order to make the pipe body inner layer and the mandrel closely fit and reduce the gap between the pipe body inner layer and the mandrel, the pipe body inner layer needs to be stretched and knotted. Make body inlayer and dabber 15 present close fit in the axial, avoid the tolerance problem of the internal diameter of body inlayer and the external diameter of dabber, body inlayer produces the fold when carrying out the wire and weaving, causes the pipe inner wall unsmooth, influences and other surgical instruments's cooperation. A wire braid is braided from the distal (non-tapered) end of the catheter to form a metal braid 1001. The outermost tube is sheathed on the metal braid 1001 to form the outer layer of the tube, and then the layers are welded together by heating. The far end of the tube body penetrates into the near end of the tube seat and penetrates out of the far end of the tube seat until the flared part of the near end of the tube body enters the inner cavity of the tube seat. The tube seat is vertically arranged with the tube body, and the tube body and the tube seat are adjusted to ensure that the near-end bell mouth of the tube body is matched with the near-end bell mouth of the tube seat and is loosened to a certain extent. Dispensing glue from the far end of the tube seat to make the glue leak along the tube body to the near end of the tube seat. Because the glue dispensing process is that the glue integrally leaks downwards along the circumference of the tube body, at the moment, the air between the tube seat and the tube body can only be discharged from the lower end due to the loose fit mode. When the glue penetrates into the waist line part where the tube body is matched with the tube seat, the glue gradually penetrates into the outer surface of the cone at the near end of the tube body. Drawing the tube body to make the tube body near-end bell mouth and the tube seat near-end bell mouth joint, and then UV curing. After the pipe body and the pipe seat are assembled, the conical buffer part is sleeved on the pipe body and the pipe seat.

While the present application has been described and illustrated with reference to particular embodiments thereof, such description and illustration are not intended to limit the present application. It will be clearly understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof within the embodiments without departing from the true spirit and scope of the present application as defined by the appended claims. The illustrations may not be drawn to scale. There may be a difference between the technical reproduction in the present application and the actual device due to variables in the manufacturing process and the like. There may be other embodiments of the application that are not specifically illustrated. The specification and drawings are to be regarded in an illustrative rather than a restrictive sense. Modifications may be made to adapt a particular situation, material, composition of matter, method, or process to the objective, spirit and scope of the present application. All such modifications are intended to be within the scope of the claims appended hereto. Although the methods disclosed herein have been described with reference to particular operations performed in a particular order, it should be understood that these operations may be combined, sub-divided, or reordered to form equivalent methods without departing from the teachings of the present application. Accordingly, unless specifically indicated herein, the order and grouping of the operations is not a limitation of the present application.

Claims

1. The utility model provides a medical catheter, it includes the body, toper buffer tube and tube socket, the body is connected to in the toper portion of tube socket, toper buffer tube cup joints in body near-end and tube socket toper portion outside, the tube socket includes toper connecting portion, tube socket main part and the tube socket inner chamber of setting in the tube socket, the tube socket inner chamber includes tube socket inner chamber distal end horn mouth, the thin waist of tube socket inner chamber and tube socket inner chamber near-end horn mouth, a serial communication port, the body includes the body straight tube and with body straight tube smooth connection's body near-end horn mouth, form the clearance between body straight tube and tube socket inner chamber distal end horn mouth and the thin waist of tube socket inner chamber, body near-end horn mouth supports and leans on tube socket inner chamber near-end horn mouth, the constraint pipe inserts in the body near-end horn mouth.

2. The medical catheter of claim 1, wherein the angle a1 of the proximal flare of the tube body is equal to the angle a2 of the proximal flare of the lumen of the hub.

3. The medical catheter of claim 2, wherein the outer diameter of the proximal flare OD1 of the tube, the outer diameter of the non-variable proximal end OD2 of the tube, and the inner diameter ID of the proximal flare of the tube are in the following ranges: OD2+0.4mm < ID < OD1 <4mm, 0.6mm < external diameter OD4 of the restraint tube < internal diameter ID of the tube body near-end bell mouth < OD1 <4mm, and the external diameter OD2 at the non-reducing position of the tube body near end is in the following range: 0.5mm < OD2<4 mm.

4. A medical catheter as in claim 3, wherein the relationship between the tube body proximal flare angle a1 and the length L of the tube body tapered section is defined by the following equation:

5. The medical catheter of claim 4, wherein the non-variable diameter portion of the proximal end of the tubular body has an outer diameter OD2< the slender inner diameter OD3-0.2mm <4 mm.

6. The medical catheter of claim 4, wherein the tube body proximal end flare angle A1 ranges from: 6 DEG < A1 < 90 deg.

7. The medical catheter of claim 4 wherein the angle B of the flare at the distal end of the hub lumen is in the range of:

。

8. the medical catheter of claim 4, wherein the spacing D between the body and the inner wall of the port of the distal flare of the lumen of the hub is in the range of:

。

9. the medical catheter of claim 1, wherein the flared proximal end of the body is formed by a conical chamfer.

10. The medical catheter of claim 1 wherein the tapered buffer tube is connected to the proximal exterior of the hub and the tapered exterior of the hub by an interference fit.

11. A method of manufacturing a medical catheter, comprising the steps of:

step 2: stretching and knotting the inner layer of the pipe body;