CN219742835U - Multifunctional internal fistula puncture needle and internal fistula puncture needle assembly - Google Patents

Abstract

The embodiment of the utility model discloses a multifunctional internal fistula puncture needle and an internal fistula puncture needle assembly. The multifunctional internal fistula puncture needle comprises a sharp needle body, a blunt needle body and a limiting part, wherein the blunt needle body is sleeved on the sharp needle body and can slide along the length direction of the sharp needle body relatively to the sharp needle body, the blunt needle body slides and switches between at least a first position and a second position under operation, the limiting part is arranged on one of the sharp needle body and the blunt needle body, the other one of the sharp needle body and the blunt needle body is provided with a limit matching part matched with the limiting part, and the limiting part is matched with the limit matching part to block the blunt needle body positioned at the second position from sliding and switching to the first position. The utility model has the functions of sharp needle puncture and protecting blood vessels and epidermis, and can greatly reduce the risk of needle puncture after being pulled out.

Description

Multifunctional internal fistula puncture needle and internal fistula puncture needle assembly

Technical Field

The utility model relates to the field of medical appliances, in particular to a multifunctional internal fistula puncture needle and an internal fistula puncture needle assembly.

Background

Hemodialysis is one of the important ways in which uremic patients sustain life. Hemodialysis requires vascular access, while arteriovenous fistulae are more than 80% of the hemodialysis patient's dialysis access. An internal fistula puncture needle is required to puncture an arteriovenous internal fistula when hemodialysis is performed.

There are two types of disposable internal fistula needles commonly used in clinic: sharp needles and blunt needles. The two internal fistula needles are designed differently on the needle point, the sharp needle point is designed in a bevel angle shape, and the needle point and the bevel are sharp, so that the internal fistula needle has a cutting function; the blunt needle is a round angle, the inclined plane is round and has no cutting function. Therefore, the sharp needle is beneficial to the puncture of internal fistula, but has injury effect on blood vessels and epidermis, especially on the puncture of the adjacent joint part, the swelling needle is possible when the patient moves slightly, and the blood vessels and epidermis are damaged again in the process of pulling out; the blunt needle is only suitable for buttonhole puncture, and is used for puncturing after forming a tunnel, so that the buttonhole puncture method has higher internal fistula infection rate and is not widely used clinically.

Therefore, there is an urgent need for a multifunctional internal fistula puncture needle that has both sharp needle penetration and blunt vascular and epidermal protection, while also greatly reducing the risk of needle stick injuries after withdrawal.

In addition, most of the existing internal fistula puncture needles have no negative pressure effect, and the puncture instant does not spontaneously leak blood, so that whether the needle head enters a blood vessel cannot be judged, and whether blood seeps or not can be observed only by a method of pinching a pipeline after filling physiological saline, so that whether the needle head is inserted into the blood vessel is judged; for patients with poor internal fistula vascular conditions, one person needs to puncture the internal fistula vascular conditions, and the other person is matched with the form of the needle drawing for development, so that labor is wasted in the centralized on-machine period, the efficiency is low, and certain limitation is caused. In order to improve the puncture success rate, a negative pressure internal fistula needle is designed clinically, but the structure is complex, the puncture process of the internal fistula needle is not suitable for the clinic, and the blood is not sucked by the negative pressure.

There is thus a great need for an internal fistula needle assembly that facilitates the observation of whether the needle tip enters the vessel to overcome the above-mentioned drawbacks, and which solves the above-mentioned problems

Disclosure of Invention

An object of an embodiment of the present utility model is to provide a multifunctional internal fistula puncture needle having a sharp needle puncture function and a blunt protection function against blood vessels and epidermis, and at the same time, the risk of needle puncture after extraction can be greatly reduced.

It is another object of an embodiment of the present utility model to provide an internal fistula needle assembly with a needle that enters the blood vessel.

In order to achieve the above purpose, the embodiment of the utility model provides a multifunctional internal fistula puncture needle, which comprises a sharp needle body, a blunt needle body and a limiting piece; the needle head of the sharp needle body is at least partially exposed out of the blunt needle body when the blunt needle body is switched to the first position, and the needle head of the sharp needle body is completely hidden in the blunt needle body when the blunt needle body is switched to the second position; the limiting piece is arranged on one of the sharp needle body and the blunt needle body, the other one of the sharp needle body and the blunt needle body is provided with a limit matching part matched with the limiting piece, and the limiting piece is matched with the limit matching part to block the blunt needle body positioned at the second position from sliding and switching to the first position.

Preferably, the multifunctional internal fistula puncture needle of the embodiment of the utility model further comprises a needle handle and a needle wing, wherein the needle handle is fixed at the tail part of the sharp needle body and is communicated with the sharp needle body, and the needle wing is fixed on the needle handle; the outer side of the needle tail of the blunt needle body is provided with a protruding part for sliding operation.

Preferably, the multifunctional internal fistula puncture needle of the embodiment of the utility model further comprises a sealing element for sealing the radial gap between the sharp needle body and the blunt needle body, and the sealing element is positioned in the blunt needle body and sleeved on the sharp needle body.

Preferably, the limit matching part is fixed on one of the sharp needle body and the blunt needle body, the sealing element is fixed on the other of the sharp needle body and the blunt needle body, the sealing element is matched with the limit matching part, the sealing element is positioned between the needle head part of the sharp needle body and the limiting element along the length direction of the sharp needle body, and the blunt needle body positioned at the second position is blocked from sliding out of the sharp needle body under the matching of the limiting element in the continuous sliding process along the direction from the needle tail part of the sharp needle body to the needle head part of the sharp needle body.

Preferably, the limiting part is an elastic body, and the limit matching part is propped against the limiting part in the process of sliding and switching the blunt needle body from the first position to the second position, so that the limiting part elastically deforms towards the direction close to the sharp needle body or the blunt needle body where the limiting part is located.

Preferably, the limiting part is arranged on the outer side wall of the sharp needle body, and the limit matching part is arranged on the inner side wall of the blunt needle body and positioned at the tail part of the blunt needle body.

Preferably, the sharp needle body comprises a first steel needle forming a needle head part of the sharp needle body and a first plastic tube seat forming a needle tail part of the sharp needle body, the first steel needle is fixed on the first plastic tube seat, and the limiting piece is an elastic finger arm integrally formed on the first plastic tube seat, or the limiting piece is an elastic finger arm formed by beveling the first plastic tube seat along the length direction of the sharp needle body.

Preferably, the blunt needle body comprises a second steel needle forming a needle head part of the blunt needle body and a second plastic tube seat forming a needle tail part of the blunt needle body, the second steel needle is fixed on the second plastic tube seat, and the limit matching part is an annular body integrally formed on the second plastic tube seat.

Preferably, the sharp needle also blocks the blunt needle from sliding out of the sharp needle during sliding of the blunt needle in the first position in a direction from the needle head of the sharp needle to the needle tail of the sharp needle.

To achieve the above object, an embodiment of the present utility model provides an internal fistula puncture needle assembly, including a multifunctional internal fistula puncture needle as set forth in any one of the above, a communication hose, a syringe for evacuating, a first current limiting clip selectively clipping the communication hose, and a second current limiting clip selectively clipping the communication hose and arranged apart from the first current limiting clip; one end of the communication hose is connected with the sharp needle body and communicated with the sharp needle body, and the other end of the communication hose is connected with the injector and communicated with the injector; the first flow limiting clamp is positioned at one end of the communication hose close to the sharp needle body; the first restriction clip is located at an end of the communication hose adjacent the syringe.

Compared with the prior art, the multifunctional internal fistula puncture needle comprises the sharp needle body, the blunt needle body and the limiting piece, the blunt needle body is sleeved on the sharp needle body and can slide along the length direction of the sharp needle body relative to the sharp needle body, the blunt needle body is at least slid and switched between the first position and the second position under operation, when the blunt needle body is switched to the first position, the needle head part of the sharp needle body is at least partially exposed out of the blunt needle body, when the blunt needle body is switched to the second position, the needle head part of the sharp needle body is completely hidden in the blunt needle body, the limiting piece is arranged on one of the sharp needle body and the blunt needle body, the other one of the sharp needle body and the blunt needle body is provided with the matched limiting piece, and the limiting piece is matched with the matched limiting piece to block the blunt needle body in the second position from sliding and switching to the first position, so that the puncture needle body in the second position has the functions of protecting the puncture needle body and the puncture needle body, and the risk of puncture needle body can be greatly reduced after the puncture needle is pulled out, and the puncture needle is simultaneously has the functions of protecting the puncture needle body. In addition, since the application embodiment provides an internal fistula puncture needle assembly comprising a multifunctional internal fistula puncture needle, a syringe, a communication hose, a first current limiting clamp capable of selectively clamping the communication hose and a second current limiting clamp capable of selectively clamping the communication hose and arranged at a distance from the first current limiting clamp, one end of the communication hose is connected with the sharp needle body and communicated with the sharp needle body, and the other end of the communication hose is connected with the syringe and communicated with the syringe; the first current limiting clamp is positioned at one end of the communication hose close to the sharp needle body, and the first current limiting clamp is positioned at one end of the communication hose close to the syringe, so that a preset vacuum negative pressure can be formed in the communication hose before the multifunctional internal fistula puncture needle is used by means of the vacuumizing effect of the syringe and the clamping effect of the first current limiting clamp and the second current limiting clamp, blood can be sucked out simply and rapidly after the puncture, and the internal fistula puncture needle assembly provided by the embodiment of the utility model is convenient for a needle head to enter a blood vessel or not.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions of the prior art, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are some embodiments of the present utility model, and other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic perspective view of an internal fistula spike assembly of an embodiment of the utility model.

Fig. 2 is a schematic perspective view of the multifunctional internal fistula needle of the internal fistula needle assembly of fig. 1 with the blunt needle body in a first position.

Fig. 3 is a schematic view of the internal structure of the multifunctional internal fistula puncture needle shown in fig. 2.

Fig. 4 is a schematic view of the internal structure of fig. 3 when the blunt needle is switched to the second position.

Reference numerals illustrate: 100. multifunctional internal fistula puncture needle; 10. a sharp needle body; 10a, a needle head of a sharp needle body; 10b, sharpening the needle tail of the needle body; 11. a first steel needle; 12. a first plastic tube seat; 20. a blunt needle body; 20a, a needle portion of the blunt needle body; 20b, the needle tail of the blunt needle body; 20c, a boss; 20d, a limit matching part; 21. a second steel needle; 22. a second plastic tube seat; 30. a limiting piece; 40. a needle handle; 50. a needle wing; 60. a seal; 1000. an internal fistula needle assembly; 200. a syringe; 300. a communication hose; 400. a first current limiting clip; 500. a second flow restricting clip.

Detailed Description

In the description of the embodiments of the present utility model, it should be understood that the terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate description of the present utility model and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present utility model. Furthermore, features defining "first", "second" may include one or more such features, either explicitly or implicitly, for distinguishing between the descriptive features, and not sequentially, and not lightly.

Referring to fig. 1-3, an internal fistula needle assembly 1000 in accordance with an embodiment of the present utility model includes a multi-functional internal fistula needle 100, a syringe 200, a communication hose 300, a first restriction clip 400, and a second restriction clip 500 disposed in spaced apart relation to the first restriction clip 400; one end of the communication hose 300 is connected to and communicates with the sharp needle body 10, and the other end of the communication hose 300 is connected to and communicates with the syringe 200; the first restriction clip 400 is positioned at one end of the communication hose 300 near the sharp needle body 10 such that the first restriction clip 400 selectively clips the communication hose 300; the first restrictor clip 400 is positioned at an end of the communication hose 300 adjacent to the syringe 200 such that the first restrictor clip 400 selectively clips the communication hose 300, and the operation of the internal fistula needle assembly of the embodiment of the utility model according to fig. 1-3 is described as follows:

firstly, the second current limiting clip 500 is in an unclamped state, and simultaneously the first current limiting clip 400 is operated to clamp the communication hose 300, then the syringe 200 is operated to vacuumize the inside of the communication hose 300, and then the second current limiting clip 500 is operated to clamp the communication hose 300, so that the communication hose 300 between the first current limiting clip 400 and the second current limiting clip 500 is in a vacuum negative pressure state, and then the multifunctional internal fistula puncture needle 100 can be operated to puncture a blood vessel of a patient, and then the second current limiting clip 500 is opened, whether the communication hose 300 has blood inflow or not is observed, and if so, the multifunctional internal fistula puncture needle 100 can be judged to puncture the blood vessel of the patient, otherwise, the multifunctional internal fistula puncture needle 100 does not puncture.

Referring to fig. 2-4, a multifunctional fistula puncture needle 100 according to an embodiment of the present utility model comprises a sharp needle body 10, a blunt needle body 20 and a limiting member 30; the blunt needle body 20 is sleeved on the sharp needle body 10 and can slide along the length direction of the sharp needle body 10 relative to the sharp needle body 10, the blunt needle body 20 slides and switches between a first position shown in fig. 3 and a second position shown in fig. 4 under operation, however, according to practical situations, the blunt needle body 20 can also have other positions so as to facilitate the sliding and switching between more positions, but not limited thereto. When the blunt needle body 20 is switched to the first position, the needle part 10a of the sharp needle body 10 is at least partially exposed outside the blunt needle body 20, so that the skin of the patient can be smoothly pierced and the blood vessel can be pierced by the needle part 10a of the sharp needle body 10; when the blunt needle body 20 is switched to the second position, the needle head 10a of the sharp needle body 10 is completely hidden in the blunt needle body 20, so that the needle head 10a of the sharp needle body 10 penetrating into a patient body is prevented from puncturing blood vessels again or damaging the blood vessels and skin again; the limiting piece 30 is arranged on the sharp needle body 10, the blunt needle body 20 is provided with a limit matching part 20c matched with the limiting piece 30, and the limiting piece 30 is matched with the limit matching part 20c to prevent the blunt needle body 20 at the second position from sliding and switching to the first position, so that the state that the needle head 10a of the sharp needle body 10 can be completely shielded after the blunt needle body 20 is switched to the second position is ensured, and secondary damage to blood vessels and skin caused by the needle head 10a of the sharp needle body 10 in the needle pulling process is ensured; of course, according to practical situations, the limiting member 30 may be disposed on the blunt needle body 20, and correspondingly, the sharp needle body 10 is provided with the limit matching portion 20c matched with the limiting member 30, so that the above-mentioned effects can be achieved through simple adaptation, and the present utility model is not limited thereto.

As shown in fig. 3 to 4, the multifunctional internal fistula puncture needle 100 according to the embodiment of the utility model further comprises a needle handle 40 and a needle wing 50, wherein the needle handle 40 is fixed on the needle tail 10b of the sharp needle body 10 and is communicated with the sharp needle body 10, so that the sharp needle body 10 can be reliably communicated with the outside through the handle 40; the needle wing 50 is fixed to the needle handle 40 so that the sharp needle body 10 is stabilized by pinching the needle wing 50; the outer side of the needle tail 20b of the blunt needle body 20 is provided with a protrusion 20d so that the blunt needle body 20 can be driven to slide along the length direction of the sharp needle body 10 by manipulating the protrusion 20 d.

As shown in fig. 3-4, the multifunctional fistula puncture needle 100 according to the embodiment of the utility model further comprises a sealing element 60, wherein the sealing element 60 is positioned in the blunt needle body 20 and sleeved on the sharp needle body 10 so as to seal the radial gap between the sharp needle body 10 and the blunt needle body 20, so as to avoid leakage of blood from the radial gap between the sharp needle body 10 and the blunt needle body 20, and further ensure that the blood flows out from the sharp needle body 10.

As shown in fig. 3-4, the sealing element 60 is fixed on the sharp needle body 10, the sealing element 60 is also matched with the matched limiting part 20c, the sealing element 60 is positioned between the needle head part 10a of the sharp needle body 10 and the limiting part 30 along the length direction of the sharp needle body 10, and in the process that the blunt needle body 20 in the second position continuously slides along the direction from the needle tail part 10b of the sharp needle body 10 to the needle head part 10a of the sharp needle body, the sealing element 60 also stops the blunt needle body 20 from sliding out of the sharp needle body 10 under the matching of the limiting part 30 so as to avoid the blunt needle body 20 from sliding out of the sharp needle body 10 along the direction from the needle tail part 10b of the sharp needle body 10 to the needle head part 10a of the sharp needle body, thereby avoiding damage to the vascular skin of a patient due to excessive sliding of the blunt needle body 20. It is understood that when the limit portion 20c is fixed to the sharp needle body 10, the seal 60 is fixed to the sharp needle body 10, and the limit portion 20c is correspondingly fixed to the blunt needle body 20, so that the above-mentioned effects can be achieved by simple adaptation, and thus the present utility model is not limited thereto.

As shown in fig. 3-4, the limiting member 30 is an elastic body, and in the process of sliding the blunt needle body 20 from the first position to the second position, the limiting portion 20c abuts against the limiting member 30, so that the limiting member 30 is elastically deformed in a direction approaching to the sharp needle body 10 or the blunt needle body 20 where the limiting member 30 is located, so as to avoid that the limiting member 30 blocks the blunt needle body 20 from sliding from the first position to the second position, and meanwhile, the free state of the limiting member 30 can block the blunt needle body 20 from sliding from the second position to the first position.

As shown in fig. 3-4, the limiting member 30 is disposed on the outer sidewall of the sharp needle body 10, and the limit matching portion 20c is disposed on the inner sidewall of the blunt needle body 20 and is located at the tail portion 20b of the blunt needle body 20, so that the structure among the limiting member 30, the limit matching portion 20c, the sharp needle body 10 and the blunt needle body 20 is more reasonable and compact.

As shown in fig. 3-4, the sharp needle body 10 includes a first steel needle 11 forming a needle head 10a of the sharp needle body 10 and a first plastic tube seat 12 forming a needle tail 10b of the sharp needle body 10, the first steel needle 11 is fixed on the first plastic tube seat 12, and the limiting member 30 is an elastic finger integrally formed on the first plastic tube seat 12, so as to facilitate the processing and forming of the sharp needle body 10 and ensure the reliability of the elastic finger, although the limiting member 30 may be an elastic finger formed by the first plastic tube seat 12 being beveled along the length direction of the sharp needle body 10 according to practical situations, but is not limited thereto.

As shown in fig. 3 to 4, the blunt needle body 20 comprises a second steel needle 21 forming a needle head 20a of the blunt needle body 20 and a second plastic tube seat 22 forming a needle tail 20b of the blunt needle body 20, the second steel needle 21 is fixed on the second plastic tube seat 22, and the limit matching part 20c is an annular body integrally formed on the second plastic tube seat 22, so as to facilitate the processing and forming of the blunt needle body 20 and ensure the blocking reliability of the limit matching part 20 and the sharp needle body 10.

As shown in fig. 3-4, during sliding movement of the blunt needle 20 in the first position in a direction from the tip portion 10a of the sharp needle 10 toward the tip portion 10b thereof, the sharp needle 10 also blocks sliding movement of the blunt needle 20 out of the sharp needle 10 to prevent sliding movement of the blunt needle 20 in the first position out of the sharp needle 10 in a direction from the tip portion 10a of the sharp needle 10 toward the tip portion 10b thereof.

Referring to fig. 2-4, the operation of the multi-functional internal fistula puncture needle 100 of the internal fistula puncture needle assembly 1000 according to the embodiment of the utility model is described as follows:

the blunt needle body 20 is located at the first position, the needle head 10a of the sharp needle body 10 is exposed outside the blunt needle body 20, the needle wing 50 is pinched first, the skin is tightened by the left hand, the needle wing 30-40 degrees is inserted by the right hand, when the inclined surface of the needle head 10a of the sharp needle body 10 is completely inserted into the skin or into the blood vessel, the first restriction clamp 400 is partially or completely opened, at this time, if the needle head 10a of the sharp needle body 10 is already inserted into the blood vessel, the negative pressure in the communication hose can suck out the blood for the first time, the operator can observe for the first time, at this time, the sharp needle body 10 is put flat, the sharp needle body 10 is then fed for 2-5 mm, the bulge 20c is pushed to push the blunt needle body 20 to the seal 60 to block the restriction part 20d, so that the blunt needle body 20 is firmly located at the second position, and the needle head 10a of the sharp needle body 10 is completely wrapped, at this time, the blunt needle body 20 can be continuously inserted into the proper position of the blood vessel of the patient, then fixed, and the dialysis line is connected.

In the drawing, the direction indicated by the arrow L is the longitudinal direction of the sharp needle 10.

Compared with the prior art, since the multifunctional internal fistula puncture needle 100 of the embodiment of the utility model comprises the sharp needle body 10, the blunt needle body 20 and the limiting piece 30, the blunt needle body 20 is sleeved on the sharp needle body 10 and can slide along the length direction of the sharp needle body 10 relative to the sharp needle body 10, the blunt needle body 20 slides and is switched between at least a first position and a second position under the operation, when the blunt needle body 20 is switched to the first position, the needle tip part of the sharp needle body 10 is exposed out of the blunt needle body 20, when the blunt needle body 20 is switched to the second position, the needle head part 10a of the sharp needle body 10 is hidden in the blunt needle body 20, the limiting piece 30 is arranged in one of the sharp needle body 10 and the blunt needle body 20, the other one of the sharp needle body 10 and the blunt needle body 20 is provided with the matched limiting piece 20c, and the limiting piece 30 blocks the needle body 20 positioned at the second position from being switched to the first position under the matched with the limiting piece 20c, so that the multifunctional internal fistula puncture needle 100 of the embodiment of the utility model has the functions of puncture of blood vessel and the protection of the puncture and the risk of the puncture wound can be greatly reduced. In addition, since the embodiment of the application provides an internal fistula puncture needle assembly 1000 including the multifunctional internal fistula puncture needle 100, the syringe 200, the communication hose 300, the first flow restriction clip 400 that selectively clips the communication hose 300, and the second flow restriction clip 500 that selectively clips the communication hose 300 and is arranged apart from the first flow restriction clip 400, and one end of the communication hose 300 is connected to and communicates with the sharp needle body 10 and the other end of the communication hose 300 is connected to and communicates with the syringe 200; the first current limiting clip 400 is located at one end of the communication hose 300 near the sharp needle body 10, and the first current limiting clip 400 is located at one end of the communication hose 300 near the syringe 200, so that a preset vacuum negative pressure can be formed in the communication hose 300 before the multifunctional fistula puncture needle 100 is used by means of the vacuumizing effect of the syringe 200 and the clamping effect of the first current limiting clip 400 and the second current limiting clip 500, so that blood can be simply and rapidly sucked out after the puncture, and the fistula puncture needle assembly 1000 of the embodiment of the utility model is convenient for whether the needle head enters the blood vessel.

The foregoing disclosure is illustrative of the present utility model and is not to be construed as limiting the scope of the utility model, but is for the convenience of those skilled in the art to understand and practice the utility model, and therefore, equivalent variations to the appended claims are intended to be encompassed by the present utility model.

Claims (10)

1. A multifunctional internal fistula puncture needle, comprising:

a sharp needle body;

the needle head of the sharp needle body is at least partially exposed out of the blunt needle body when the blunt needle body is switched to the first position, and the needle head of the sharp needle body is completely hidden in the blunt needle body when the blunt needle body is switched to the second position; and

the limiting piece is arranged on one of the sharp needle body and the blunt needle body, the other one of the sharp needle body and the blunt needle body is provided with a limit matching part matched with the limiting piece, and the limiting piece is matched with the limit matching part to block the blunt needle body positioned at the second position from sliding and switching to the first position.

2. The multifunctional internal fistula puncture needle of claim 1, further comprising a needle handle and a needle wing, the needle handle being secured to and in communication with a needle tail of the sharp needle, the needle wing being secured to the needle handle; the outer side of the needle tail of the blunt needle body is provided with a protruding part for sliding operation.

3. The multi-functional internal fistula puncture needle of claim 1, further comprising a seal for sealing a radial gap between the sharp needle and the blunt needle, the seal being located within and over the sharp needle.

4. The multifunction internal fistula puncture needle of claim 3, wherein the limit fitting is secured to one of the sharp needle and the blunt needle, the seal is secured to the other of the sharp needle and the blunt needle, the seal is further engaged with the limit fitting, the seal is located between the tip portion of the sharp needle and the stop along a length of the sharp needle, and the blunt needle in the second position is further prevented from sliding out of the sharp needle during continued sliding movement from the tip portion of the sharp needle toward the tip portion thereof, in cooperation with the stop.

5. The multifunctional internal fistula puncture needle of claim 1, wherein the limiting member is an elastic body, and the limit matching portion presses against the limiting member in the process of sliding and switching the blunt needle body from the first position to the second position, so that the limiting member is elastically deformed in a direction approaching to a sharp needle body or a blunt needle body where the limiting member is located.

6. The multifunctional internal fistula adapter of claim 5, wherein the limiter is disposed on an outer sidewall of the sharp needle, and the limiter is disposed on an inner sidewall of the blunt needle and is disposed at a distal end of the blunt needle.

7. The multifunctional internal fistula adapter of claim 6, wherein the sharp needle body comprises a first steel needle forming a needle head of the sharp needle body and a first plastic tube seat forming a needle tail of the sharp needle body, the first steel needle being fixed to the first plastic tube seat, the stop being an elastic finger integrally formed on the first plastic tube seat, or the stop being an elastic finger formed by beveling the first plastic tube seat along a length direction of the sharp needle body.

8. The multifunctional internal fistula adapter of claim 6 wherein the blunt needle body comprises a second steel needle forming a needle head portion of the blunt needle body and a second plastic socket forming a needle tail portion of the blunt needle body, the second steel needle being secured to the second plastic socket, the restraining portion being an annular body integrally formed with the second plastic socket.

9. The multi-functional internal fistula puncture needle of claim 1, wherein the sharp needle further blocks sliding of the blunt needle out of the sharp needle during sliding of the blunt needle in the first position in a direction from the needle tip of the sharp needle toward the needle tail thereof.

10. An internal fistula needle assembly, comprising:

the multifunctional internal fistula puncture needle of any one of claims 1-9;

a syringe for evacuating;

the other end of the communication hose is connected with the injector and is communicated with the injector;

a first flow restricting clip selectively clipping the communication hose, the first flow restricting clip being located at one end of the communication hose near the sharp needle body; and

a second flow restricting clip selectively gripping the communication hose and disposed in spaced relation to the first flow restricting clip, the first flow restricting clip being located at an end of the communication hose adjacent the syringe.