CN211751455U

CN211751455U - Silica gel central venous catheter

Info

Publication number: CN211751455U
Application number: CN201921712994.4U
Authority: CN
Inventors: 姜小波; 程宇; 赵宗煌
Original assignee: Foshan Special Medical Catheter Co ltd
Current assignee: Foshan Special Medical Catheter Co ltd
Priority date: 2019-10-12
Filing date: 2019-10-12
Publication date: 2020-10-27
Anticipated expiration: 2029-10-12

Abstract

The utility model provides a silica gel central venous catheter, belonging to the technical field of medical appliances, comprising a silica gel tube body; the epitaxial tube body is a thermoplastic epitaxial tube; the connector is used for the intercommunication fixed silica gel body and epitaxial tube body, the inside of connector is provided with the intercommunication chamber way, the one end of connector supplies the silica gel body wears to establish fixedly and rather than intercommunication each other, the other end with the fixed intercommunication each other of epitaxial tube body can make the probability that the epitaxial tube body produced the bubble obviously reduce, especially adopts polyurethane epitaxial tube, does not have the bubble basically and produces to reduce patient's panic and ann, alleviate nurse's work load.

Description

Silica gel central venous catheter

Technical Field

The utility model relates to the technical field of medical equipment, concretely relates to silica gel central venous catheter.

Background

The central venous catheter (PICC catheter) is a catheter which is placed into a central vein through a peripheral vein, is used for providing middle-term to long-term venous treatment for a patient, can greatly reduce the pain of the patient caused by frequent venipuncture, avoids the influence and damage of irritant medicines on the vein, and has long retention time and low complication incidence rate. The existing PICC catheters can be divided into two types, one type is a silica gel central venous catheter (a silica gel PICC catheter) which is made of a silica gel material through a heating and curing process; the other type is a polyurethane central venous catheter (polyurethane PICC catheter) which is made of polyurethane materials through hot melting and cooling and then is integrally formed, and the polyurethane central venous catheter is also called a high-pressure-resistant injection type PICC catheter. The performances of the silica gel PICC catheter and the polyurethane PICC catheter are obviously different, and doctors can select the applicable PICC catheter according to the treatment content when the catheter is used, and the catheter can not be mutually replaced (see the clinical application of the high-pressure-resistant injection type PICC and the silica gel PICC catheter, Von Yulin, No. 13 vol.20 of the world latest medical information abstracts 2013, 467-.

Wherein, silica gel PICC pipe has little to vascular damage, and biocompatibility is good, and long-term indwelling physicochemical property can not change, and is safe high, advantage that the comfort level is good, uses extensively in clinical practice in-process. However, the applicant finds in clinical practice that the silica gel PICC catheter is very easy to generate bubbles in the use process, so that a patient is panic and uncomfortable, air embolism is easily caused or aggravated, a nurse needs to regularly pump air out of the silica gel PICC catheter, the workload of the nurse is increased, the air pumping work needs to be quite skilled and fast to react, the operation difficulty is high, and time and labor are wasted.

SUMMERY OF THE UTILITY MODEL

Therefore, the to-be-solved technical problem of the utility model lies in overcoming the defect that the bubble easily appears in the central venous catheter of silica gel among the prior art to a central venous catheter of silica gel is provided.

The utility model provides a silica gel central venous catheter, include:

a silica gel tube body;

the epitaxial tube body is a thermoplastic epitaxial tube;

the connector is used for communicating and fixing the silica gel tube body and the epitaxial tube body, a communicating cavity is arranged in the connector, one end of the connector is used for the silica gel tube body to be fixed and communicated with the silica gel tube body, and the other end of the connector is communicated with the epitaxial tube body fixedly and mutually.

Further, the thermoplastic extension pipe is any one of a polyethylene extension pipe, a polyvinyl chloride extension pipe, a polyurethane extension pipe and a polyethylene terephthalate extension pipe.

Further, the connector includes:

the pressure reducing sleeve is internally provided with a first cavity for the silica gel pipe body to penetrate through;

the joint seat, inside be provided with the second cavity that first cavity communicates each other, the joint seat is located to be provided with in the second cavity and stretches into supply in the first cavity the connecting pipe that silica gel body cover was established and is fixed, the joint seat be located the one end in the outside with the mutual joint of decompression sleeve.

Further, the first cavity includes:

the first cavity channel is positioned at one end, close to the joint seat, of the first cavity channel and is used for the connecting pipe to extend into;

the second cavity channel is positioned at one end far away from the joint seat and is coaxial with the first cavity channel;

the width that first chamber said is greater than the width that the second chamber said, under the non-deformation state the external diameter of silica gel body is greater than under the width that the second chamber said and the non-deformation state the external diameter of silica gel body is less than the width that the first chamber said.

Further, the difference between the outer diameter of the silica gel tube body and the width of the second cavity channel in the non-deformation state is 0.1-2 times of the thickness of the silica gel tube body.

Further, the difference between the width of the second cavity and the outer diameter of the connecting pipe is 0.1-0.5 times of the thickness of the silica gel pipe body in a non-deformation state.

Further, the connector further includes:

the first slope part is positioned at the end part of the pressure reducing sleeve close to one end of the joint seat, and the width of the end of the first slope part close to the joint seat is smaller than that of the end of the first slope part far away from the joint seat;

and the second slope part is positioned at the end part of the joint seat close to one end of the pressure reducing sleeve, and the end surfaces of the second slope part and the first slope part are mutually abutted.

Further, silica gel central venous catheter still includes:

the clamping groove is arranged at one end, far away from the pressure reducing sleeve, of the joint seat in a surrounding mode;

the silica gel base, the center is provided with the through-hole, the silica gel base imbeds behind the draw-in groove and is located for fixed cover the joint seat just covers the epitaxial tube of draw-in groove.

Further, the connector still including being located recess on the decompression sleeve with be located arch on the joint seat, protruding with the recess is mutually supported in order to realize the joint of decompression sleeve and joint seat.

The utility model discloses technical scheme has following advantage:

1. the utility model provides a silica gel central venous catheter, which comprises a silica gel tube body, an epitaxial tube body and a connector, wherein one end of the connector is used for the silica gel tube body to be fixedly arranged and mutually communicated, the other end is fixedly mutually communicated with the epitaxial tube body, so that the entire PICC catheter is interconnected and secured to one another, can be used for intravenous drug delivery, wherein, the PICC catheter keeps good histocompatibility and compliance by adopting the silica gel catheter body, moreover, the thermoplastic extension tube is adopted, for example, the polyethylene extension tube, the polyvinyl chloride extension tube, the polyurethane extension tube or the polyethylene terephthalate extension tube is adopted, compared with the silica gel extension tube, the probability of generating bubbles of the silica gel PICC catheter is obviously reduced, and particularly, the polyurethane extension tube is adopted, so that no bubbles are generated basically, the panic and the insecurity of a patient are reduced, and the workload of a nurse is reduced.

2. The utility model provides a silica gel central venous catheter, the connector includes decompression sleeve and joint seat, and decompression sleeve's inside is provided with the first cavity that supplies the silica gel body to wear to establish, the inside of joint seat be provided with the second cavity that first cavity communicates each other, the joint seat is provided with in the second cavity and stretches into supply in the first cavity fixed connecting pipe is established to silica gel body cover, the joint seat be located the outside one end with the mutual joint of decompression sleeve to the inboard of silica gel PICC pipe, the elasticity that utilizes the silica gel body can be established and fix on the connecting pipe with its cover to make the silica gel body communicate each other through connecting pipe and second cavity, and the outside, through joint seat and the mutual joint of decompression sleeve, realized both to be connected.

3. The utility model provides a silica gel central venous catheter, first cavity includes that first chamber says and second chamber says, and first chamber says and is located first chamber and says and be located the one end that is close to the joint seat, and the second chamber says, be located the one end of keeping away from the joint seat and with first chamber says coaxial setting, the width that first chamber was said is greater than the width that the second chamber was said, the external diameter of silica gel body is greater than the width that the second chamber was said just is less than the width that first chamber was said for the silica gel body both can conveniently stretch into the decompression sleeve from the one end that the great first chamber of width was said, can utilize again that self elasticity is crowded to go into in the less second chamber of width and be fixed in the second chamber, makes the silica gel body be difficult for droing, and installation and operation is convenient quick moreover.

4. The utility model provides a silica gel central venous catheter, under the non-deformation state the external diameter of silica gel body with the difference of the width that the second chamber was said is 0.1 ~ 2 times of silica gel body thickness for the silica gel body can enough utilize self elasticity to wear to establish into the second chamber and say, can closely laminate with decompression telescopic inner wall again under the rebound effect, effectively improves the condition that the air got into the silica gel body and made whole PICC pipe bubble appear from the second chamber.

5. The utility model provides a silica gel central venous catheter, the difference between the width that the second chamber was said and the external diameter of connecting pipe is under the non-deformation state 0.1 ~ 0.5 times of silica gel body thickness for the silica gel body can fasten the cover and establish on the connecting pipe, utilizes self elasticity to crowd into the connecting pipe under compression state and the clearance that the decompression sleeve is located between the second chamber, again closely laminates with the telescopic inner wall of decompression under the rebound action, effectively improves the air and says the silica gel body and make whole PICC pipe the condition that the bubble appears by first chamber.

6. The utility model provides a silica gel central venous catheter, the connector is still including being located the first slope that decompression sleeve is close to the tip of joint seat one end is with being located the second slope that the joint seat is close to the tip of decompression sleeve one end, first slope is located the width that is close to the one end of joint seat and is less than first slope is located the width of keeping away from joint seat one end, the mutual butt of terminal surface of second slope and first slope can improve the compactness of being connected between joint seat and the decompression sleeve, and the condition that the reduction air got into by the clearance between joint seat and the decompression sleeve takes place, easily aims at moreover, installation convenient operation.

7. The utility model provides a silica gel central venous catheter, including silica gel base and draw-in groove, the draw-in groove encircle set up in the joint seat is located and keeps away from decompression telescopic one end during the use, locates epitaxial pipe box earlier the joint seat just covers on the draw-in groove of joint seat, then with silica gel base embedding draw-in groove, not only can further fix epitaxial pipe and joint seat, can make things convenient for the patient to use moreover, it is more comfortable.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural view of a silicone tube and a connector provided in embodiment 1 of the present invention;

FIG. 2 is an enlarged view of portion A of FIG. 1;

fig. 3 is a schematic structural view of a connector and an epitaxial tube body provided in embodiment 1 of the present invention;

FIG. 4 is an enlarged view of portion B of FIG. 3;

description of reference numerals:

1. a silica gel tube body; 2. an extension pipe joint; 21. a body of the epitaxial tube; 3. a connector; 31. a pressure reducing sleeve; 311. a first cavity; 311a, a first cavity; 311b, a second cavity; 312. a first slope portion; 313. a groove; 32. a joint base; 321. a second cavity; 322. a connecting pipe; 323. a second slope portion; 324. a card slot; 325. a silica gel base; 326. and (4) protruding.

Detailed Description

The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings, and obviously, the described embodiments are some, but not all embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" 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 is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Furthermore, the technical features mentioned in the different embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.

Example 1

A specific embodiment of the central silica gel venous catheter shown in fig. 1 and 3 comprises a silica gel tube 1, an epitaxial tube 21 and a connector 3 which is arranged between the silica gel tube 1 and the epitaxial tube 21 and used for communicating and fixing the silica gel tube 1 and the epitaxial tube 21.

The epitaxial tube body 21 is a thermoplastic epitaxial tube, and the thermoplastic epitaxial tube is any one of a polyethylene epitaxial tube, a polyvinyl chloride epitaxial tube, a polyurethane epitaxial tube and a polyethylene terephthalate epitaxial tube, and in this embodiment, the epitaxial tube body 21 is a polyurethane epitaxial tube. The PICC catheter can keep good histocompatibility and compliance by adopting the silica gel catheter body 1, and the thermoplastic plastic epitaxial catheter body 21 is adopted, such as a polyethylene epitaxial catheter, a polyvinyl chloride epitaxial catheter, a polyurethane epitaxial catheter or a polyethylene glycol terephthalate epitaxial catheter.

The inside of connector 3 is provided with the intercommunication chamber and says, the one end of connector 3 supplies silica gel body 1 wears to establish fixed and intercommunication each other, the other end with the fixed intercommunication each other of epitaxial tube body 21 for whole PICC pipe communicates each other and reciprocal anchorage can be used for intravenous drug delivery. Specifically, connector 3 includes decompression sleeve 31 and adapter 32, decompression sleeve 31 is inside to be provided with the first cavity 311 that supplies silica gel body 1 to wear to establish, adapter 32 is inside be provided with the second cavity 321 that first cavity 311 communicates each other, be provided with on the adapter 32 and stretch into supply in the first cavity 311 silica gel body 1 cover is established and fixed connecting pipe 322, and the internal diameter of silica gel body 1 is less than the external diameter of connecting pipe 322, first cavity 311 and second cavity 321 pass through connecting pipe 322 communicate each other, adapter 32 be located the one end in the outside with the mutual joint of decompression sleeve 31, when the installation uses, to the inside of silica gel PICC pipe, utilize the elasticity of silica gel body 1 self can establish its cover and fix outside connecting pipe 322 to make silica gel body 1 communicate each other through connecting pipe 322 and second cavity 321, and for the outside of silica gel PICC pipe, through the mutual joint of connector seat 32 and decompression sleeve 31, realized connecting between them. In this embodiment, the connector 3 further includes a groove 313 on the pressure reducing sleeve 31 and a protrusion 326 on the joint seat 32, and the protrusion 326 and the groove 313 are matched with each other to realize the clamping connection between the pressure reducing sleeve 31 and the joint seat 32.

As shown in fig. 2, the first cavity 311 includes a first cavity 311a for the connection pipe 322 to extend into and a second cavity 311b communicated with the first cavity 311a, the first cavity 311a is located at an end close to the joint seat 32, the second cavity 311b is located at an end far from the joint seat 32, the width of the first cavity 311a is greater than that of the second cavity 311b, and the outer diameter of the silicone tube 1 in the non-deformed state is greater than that of the second cavity 311b and less than that of the first cavity 311 a. By utilizing the relationship between the outer diameter of the silica gel tube body 1 and the widths of the first cavity 311a and the second cavity 311b, the silica gel tube body 1 can conveniently stretch into the pressure reducing sleeve 31 from one end of the first cavity 311a with larger width, and can be relatively fixed in the second cavity 311b with smaller width by utilizing the elasticity of the silica gel tube body 1, so that the silica gel tube body 1 is not easy to fall off under the action of non-external force, and the installation and the operation are convenient and quick.

Under the non-deformation state the external diameter of silica gel body 1 with the difference of the width of second chamber way 311b is 0.1 ~ 2 times of the 1 thickness of silica gel body for silica gel body 1 can enough utilize self elasticity to wear to establish in second chamber way 311b, can closely laminate with the inner wall of decompression sleeve 31 under the rebound effect again, effectively improves the air and gets into silica gel body 1 and make the condition that the bubble appears in whole PICC pipe from second chamber way 311 b. In this embodiment, the difference between the outer diameter of the silicone tube 1 and the width of the second cavity 311b in the non-deformed state is 0.8 times the thickness of the silicone tube 1.

The difference between the width of the second cavity 311b and the outer diameter of the connecting pipe 322 is in a non-deformation state, the thickness of the silica gel pipe body 1 is 0.1-0.8 times that of the silica gel pipe body, the silica gel pipe body 1 can be tightly sleeved on the connecting pipe 322, the connecting pipe 322 and the pressure reducing sleeve 31 are squeezed into a gap between the second cavity 311b by the aid of elasticity of the silica gel pipe body in a compression state, the silica gel pipe body is tightly attached to the inner wall of the pressure reducing sleeve 31 under the action of resilience, and air is effectively improved to enter the silica gel pipe body 1 from the first cavity 311a so that the whole PICC catheter generates bubbles. In this embodiment, the difference between the width of the second cavity 311b and the outer diameter of the connecting tube 322 is 0.5 times the thickness of the silicone tube 1 in the non-deformation state.

As shown in fig. 3 and 4, the right end of the epitaxial tube body 21 is provided with an epitaxial tube joint 2, the epitaxial tube joint 2 can be a thermoplastic epitaxial tube joint, such as a polyethylene epitaxial tube joint, a polyvinyl chloride epitaxial tube joint, a polyurethane epitaxial tube joint or a polyethylene terephthalate epitaxial tube joint, in this embodiment, a polyurethane epitaxial tube joint is adopted, the thermoplastic epitaxial tube joint and the thermoplastic epitaxial tube joint can be formed by hot melting and cooling plastic materials, the silicone tube body 1 can be formed by heating and curing silicone, because the two are completely opposite forming processes, it is very difficult to connect the polyurethane epitaxial tube to the silicone tube body or the silicone epitaxial tube to the polyurethane tube body in the prior art, and therefore, the prior art adopts a polyurethane epitaxial tube to connect the polyurethane tube body, form full polyurethane PICC pipe, perhaps adopt silica gel epitaxial growth pipe to connect silica gel body 1, form full silica gel PICC pipe. In the embodiment, in order to solve the bubble problem, the applicant must stably and hermetically connect the polyurethane epitaxial tube to the silicone tube body 1, and in the continuous research process, by selecting the connector 3 formed by cooling the plastic material through hot melting with the above structure, the connection between the silicone tube body 1 and the thermoplastic epitaxial tube body 21 is realized through the connector 3, specifically, in the installation and use process, firstly, one end of the silicone tube body 1 is inserted into the pressure reducing sleeve 31, then, the other end of the silicone tube body 1 is sleeved and fixed on the connecting tube 322, the connecting tube 322 is inserted into the first cavity 311a until the protrusion 326 of the joint seat 32 and the groove 313 of the pressure reducing sleeve 31 are clamped, so as to realize the communication and fixation between the silicone tube body 1 and the connector 3, then, the communication and fixation between the connector 3 and the epitaxial tube body 21 can be realized through an adhesive or through a hot melting injection molding process in advance, can be through 3 with silica gel body 1 and extension tube body 21 intercommunication and fixed of connector, realize the equipment of silica gel central venous catheter.

In this embodiment, the connector 3 includes a first slope 312 located at an end portion of the pressure reducing sleeve 31 close to one end of the joint seat 32 and a second slope 323 located at an end portion of the joint seat 32 close to one end of the pressure reducing sleeve 31, a width of the first slope 312 located at one end close to the joint seat 32 is smaller than a width of the first slope 312 located at one end away from the joint seat 32, and the second slope 323 abuts against an end surface of the first slope 312, so that tightness of connection between the joint seat 32 and the pressure reducing sleeve 31 can be improved, occurrence of a situation that air enters from a gap between the joint seat 32 and the pressure reducing sleeve 31 is reduced, alignment is easy, and installation and operation are convenient.

As shown in fig. 1 and 4, in this embodiment, the central venous catheter of silica gel further includes a silica gel base 325 and a clamping groove 324, the clamping groove 324 surrounds the one end that is located and kept away from the adapter 32 the decompression sleeve 31, the center of the silica gel base 325 is provided with a through hole, the silica gel base 325 is embedded into the clamping groove 324 and then is used for fixing the sleeve and locates the adapter 32 and cover the extension tube of the clamping groove 324, when the assembly is used, the extension tube is firstly sleeved on the adapter 32 and covers the clamping groove 324 of the adapter 32, then the silica gel base 325 is embedded into the clamping groove 324, so that the extension tube and the adapter 32 can be further fixed, and the central venous catheter of silica gel can be conveniently used by a patient and is more.

Example 2

The present embodiment differs from embodiment 1 only in that the epitaxial tube body 21 used in the present embodiment is a polyethylene epitaxial tube, and the epitaxial tube joint 2 used is a polyethylene epitaxial tube joint.

Example 3

The present embodiment differs from embodiment 1 only in that the epitaxial tube body 21 used in the present embodiment is a pvc epitaxial tube, and the epitaxial tube joint 2 used in the present embodiment is a pvc epitaxial tube joint.

Example 4

The difference between this embodiment and embodiment 1 is only that, in this embodiment, the difference between the outer diameter of the silicone tube body 1 in the non-deformed state and the width of the second cavity 311b is 0.

Example 5

The difference between this embodiment and embodiment 1 is only that, in this embodiment, the difference between the width of the second cavity 311b and the outer diameter of the connecting tube 322 is 0.9 times the thickness of the silicone tube body 1 in the non-deformed state.

Comparative example 1

The present comparative example differs from example 1 only in that the epitaxial tube body 21 employed in the present comparative example is a silica gel tube body.

Examples of the experiments

The following operations were carried out using the silica gel central venous catheters of examples 1 to 5 and comparative example 1, respectively, following the clinical application method, by first filling the entire silica gel PICC catheter with physiological saline, purging air, simultaneously sealing the extension tube connector with the infusion connector, then immersing 3/4 lengths of the silica gel tube body of the PICC catheter under a water surface of 12cm water column height (this height corresponds to the human venous pressure), and observing and recording the number of bubbles generated in the extension tube within 7 days.

As can be seen from the above table, compared with comparative example 1, the silica gel PICC catheter of the present invention in examples 1-5 can significantly reduce the generation of bubbles, and the polyurethane extension tube is superior to polyethylene extension tube and polyvinyl chloride extension tube in example 1, compared with examples 4-5, the silica gel PICC catheter in example 1 can further reduce the generation of bubbles by controlling the parameters.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious changes and modifications may be made without departing from the scope of the present invention.

Claims

1. A silica gel central venous catheter, comprising:

a silica gel tube body (1);

the epitaxial tube comprises an epitaxial tube body (21), wherein the epitaxial tube body (21) is a thermoplastic epitaxial tube;

connector (3) for the intercommunication is fixed silica gel body (1) and epitaxial tube body (21), the inside of connector (3) is provided with the intercommunication chamber way, the one end of connector (3) supplies silica gel body (1) wear to establish fixed and with silica gel body (1) communicates each other, the other end with epitaxial tube body (21) are fixed and communicate each other.

2. The central silicone venous catheter of claim 1, wherein the thermoplastic extension tube is any one of a polyethylene extension tube, a polyvinyl chloride extension tube, a polyurethane extension tube, and a polyethylene terephthalate extension tube.

3. The central silicone venous catheter of claim 1 or 2, wherein the connector (3) comprises:

the pressure reducing sleeve (31) is internally provided with a first cavity (311) for the silica gel tube body (1) to penetrate through;

joint base (32), inside be provided with second cavity (321) that first cavity (311) communicates each other, joint base (32) are provided with and stretch into supply in first cavity (311) silica gel body (1) cover is established and fixed connecting pipe (322), first cavity (311) and second cavity (321) pass through connecting pipe (322) are linked together, joint base (32) be located the one end in the outside with decompression sleeve (31) joint each other.

4. The central silicone venous catheter of claim 3, wherein the first cavity (311) comprises:

a first cavity (311a) which is positioned at one end close to the joint seat (32) and is used for the connection pipe (322) to extend into;

the second cavity (311b) is positioned at one end far away from the joint seat (32) and communicated with the first cavity (311 a);

the width of first chamber way (311a) is greater than the width of second chamber way (311b), under the non-deformation state the external diameter of silica gel body (1) is greater than under the width of second chamber way (311b) and the non-deformation state the external diameter of silica gel body (1) is less than the width of first chamber way (311 a).

5. The central silica gel venous catheter as claimed in claim 4, wherein the difference between the outer diameter of the silica gel tube (1) and the width of the second lumen (311b) in the undeformed state is 0.1-2 times the thickness of the silica gel tube (1).

6. The central silica gel venous catheter as claimed in claim 4 or 5, wherein the difference between the width of the second lumen (311b) and the outer diameter of the connecting tube (322) is 0.1 to 0.5 times the thickness of the silica gel tube (1) in the undeformed state.

7. The central silicone venous catheter of claim 3, wherein the connector (3) further comprises:

the first slope part (312) is positioned at the end part of the decompression sleeve (31) close to one end of the joint seat (32), and the width of the first slope part (312) at one end close to the joint seat (32) is smaller than that of the first slope part (312) at one end far away from the joint seat (32);

and a second slope section (323) located at an end portion of the joint base (32) near one end of the decompression sleeve (31), the second slope section (323) abutting against an end surface of the first slope section (312).

8. The central silicone venous catheter of claim 3, further comprising:

the clamping groove (324) is arranged around one end of the connector base (32) far away from the pressure reducing sleeve (31);

silica gel base (325), the center is provided with the through-hole, silica gel base (325) imbeds behind draw-in groove (324) and is used for fixed cover to locate joint seat (32) just covers the epitaxial tube of draw-in groove (324).

9. The central silica gel venous catheter as claimed in claim 3, characterized in that the connector (3) further comprises a recess (313) on the decompression sleeve (31) and a projection (326) on the hub (32), the projection (326) cooperating with the recess (313) to effect the snap-fit of the decompression sleeve (31) with the hub (32).