JP6933386B2 - Indwelling needle - Google Patents

Description

The present invention relates mainly to an indwelling needle used in a state of being inserted into a blood vessel for the purpose of dialysis treatment or the like.

A single-needle type indwelling needle that is used while being inserted into a blood vessel for the purpose of dialysis treatment (blood circulation) is, for example, an outer tube that serves as a tube for discharging (bleeding) blood in the blood vessel to the outside of the body. And, after being discharged to the outside of the body, it is passed through a dialysis device (dialyzer) and has an inner tube for returning (returning) the purified blood to the body, so it is basically double. It has a tubular structure (see Patent Documents 1 to 4).

In the example of Patent Document 2, the conduit 20 of the hub 10 into which an injection needle for puncturing the blood vessel can be inserted to insert the outer tube into the blood vessel is the outer tube and is connected to the root portion of the hub 10. The metal pipe 82 of the axial flow device 80 is an inner pipe. In this example, the blood in the blood vessel is taken into the conduit 20 through the gap between the conduit 20 and the metal tube 84, and then is guided to the dialysis machine from the tube 104, which is a blood discharge hole, via the branch point 98. .. The purified blood passes through the metal tube 82 through the tube 94, which is the return hole of the blood, at the root of the biaxial flow device 80, and is returned to the blood vessel. The blood flow (circulation) is the same in other examples (Patent Documents 1, 3, and 4).

Since the branch point 98 of Patent Document 2 is a portion where the outer pipe (conduit 20) and the inner pipe (metal pipe 82) intersect (column 7, lines 29 to 32), the inner pipe is always outside at the branch point 98. It will penetrate the pipe. This structure is also common to other Patent Documents 1, 3 and 4. Therefore, at the branch point 98, the outer tube is liquid-tight (watertight) around the part where the inner tube penetrates so that the blood discharged from the blood vessel and the blood returned from the dialysis device are not mixed. Filling of a filler (liquid-tight material) such as a sealing material or an O-ring is indispensable as a process for ensuring the above (paragraphs 0030 and 0047 of Patent Document 4, FIG. 2, FIG. 4, FIG. 6).

The branch point 98 is a space formed near the hub 10 of the biaxial flow device 80 having a bifurcated shape, and is located at a position separated from the blood discharge hole (tube 104) and the blood return hole (tube 94). It is in. Therefore, in order to ensure liquid tightness at the branch point 98, the filler must be inserted deeper than the end face of the return hole toward the branch point 98 (paragraph 0030 of Patent Document 4, FIG. 4). .. For this reason, for mounting (inserting) the filler into the outer pipe, an arm-shaped inserter having a distance (stroke) from the return hole to the filler insertion position (branch point 98) is used, and the inserter is used. Since the reciprocating motion must be used, the structure of the indwelling needle to which the filler is mounted (built-in) is complicated, and the work of mounting the filler is not easy. It is also difficult to confirm from the return hole whether or not the filler is surely filled in the determined position.

In the example of the indwelling needle for blood transfusion, the structure is such that the inner needle 8 as the inner tube is inserted into the outer tube (outer needle 4), and faces the branch flow path on the root side of the outer tube to which the infusion solution is supplied. There is an example in which a plug 6 that closes after detachment is inserted while the inner needle 8 is inserted at the position (Patent Document 6). In this example, the infusion solution supplied from the tube 7 connected to the outer tube is introduced into the blood vessel from the needle tip 81 through the side hole 82 formed in the inner needle 8. The outer tube merely serves as a guide when the inner needle 8 is inserted and an infusion solution after the inner needle 8 is removed, and a state in which the liquid passing through the tube 7 and the liquid passing through the inner needle 8 and the outer tube are mixed. Therefore, it does not have a function of draining and returning blood in the blood vessel (paragraphs 0031 to 0067). Further, since the plug body 6 is axially fitted to the enlarged diameter portion on the root side of the hub 3 forming the branch flow path and mounted on the hub 3, the mounting work of the plug body 6 itself is described in Patent Documents 1 to 4. There is no fundamental difference.

Unlike Patent Document 2, the inner pipe inserts (penetrates) the inside of the outer pipe, but the trocar at the tip of the outer pipe (primary pipe 2) can freely appear and disappear from the opening 16 formed at the tip of the outer pipe. If the (tube needle) 24 is inserted so as to be reciprocally movable in the axial direction, a state in which the return flow path 27 and the discharge flow path 25 intersect, or a state in which one of them penetrates the other is avoided (Patent Document). 5). In this example, the trocar is inserted into the outer tube as a partition wall passing through the center of the outer tube so as to divide the inside of the outer tube (cylindrical space) into both sides, so that the inside of the outer tube is a flow path for blood discharge. It is divided into 25 and a return flow path 27.

Japanese Unexamined Patent Publication No. 53-93686 (Page 3, Top Left Column, 13th Line to Page 4, Bottom Left Column, Line 7, Figures 1 to 4) Japanese Patent Publication No. 60-27538 (Gazette column 5, line 10 to column 10, line 14, Fig. 2 to Fig. 4) UK Patent Application Publication No. 2032778 (Fig. 2) Japanese Patent No. 6344944 (paragraphs 0022 to 0046, FIGS. 1 to 5) U.S. Pat. No. 4180068 (FIGS. 1-8) Japanese Unexamined Patent Publication No. 10-179734 (paragraphs 0031 to 0069, FIGS. 1, 2)

However, since the trocar inserted into the outer pipe of Patent Document 5 reciprocates while the outer peripheral surface of the trocar reciprocates while contacting (sliding) the inner peripheral surface of the outer pipe, the discharge flow path and the return flow path are completely separated. In order to ensure the liquidtightness between the outer peripheral surface of the trocar and the inner peripheral surface of the outer pipe over the entire length of the section where the outer pipe is divided into the discharge flow path and the return flow path. You will need it. In Patent Document 5, a groove 30 is formed on the inner peripheral surface of the outer pipe along the axial direction, while a protrusion (rail) 31 that slides along the groove 30 is provided on the outer peripheral surface of the trocar while being fitted in the groove 30. It is formed (FIGS. 3 and 4).

However, since the liquidtightness between the discharge flow path and the return flow path is not always ensured only by fitting the groove 30 and the protrusion 31, Patent Document 4 describes that either the groove 30 or the protrusion 31 has a liquid tightness. It will be necessary to install such a filler.

Based on the above background, the present invention proposes an indwelling needle having a structure that facilitates and ensures liquid tightness between both flow paths in order to separate the discharge flow path and the return flow path in Patent Document 5. It is a thing.

The indwelling needle according to claim 1 is a hollow cross-section discharge pipe that is inserted into a blood vessel and discharges blood in the blood vessel from the blood vessel to the outside of the blood vessel, and is inserted into the blood vessel and integrated with the discharge pipe. A return tube having a hollow cross section for returning blood once discharged from the blood vessel into the blood vessel is provided.
An outflow hole for discharging blood to the outside of the blood vessel is formed in a portion of the discharge pipe located inside the blood vessel, and a discharge hole for discharging blood to the outside of the discharge pipe is formed in a portion of the discharge pipe located outside the blood vessel. Formed,
An inflow hole for allowing blood to flow into the blood vessel is formed in a portion of the return tube located inside the blood vessel, and a return hole for returning blood from outside the return tube is formed in a portion of the return tube located outside the blood vessel. Formed,
The inside of either the discharge pipe or the return pipe has a cross-sectional area through which the inner needle that punctures the blood vessel can be inserted, and the discharge pipe or the return pipe through which the inner needle is inserted is said to have a cross-sectional area. An opening is formed at the outer end located on the outer side of the blood vessel, and the outer end of the blood existing inside either the discharge tube or the return tube is formed on the outer end surface of the blood vessel at the outer end. It is a constituent requirement that the hemostatic valve that allows the insertion of the inner needle is arranged in close contact with the blood vessel while preventing the outflow from the portion to the outside of the blood vessel.

The "hollow cross section" means that if both the discharge pipe and the return pipe have a hollow shape, the cross-sectional shape may be cylindrical, polygonal, semi-cylindrical, crescent-shaped (U-shaped), or the like. As shown in FIGS. 1 and 3, one of the discharge pipe 2 and the return pipe 3 is the outer pipe, and the other is the inside of the other (outer pipe). In addition to being combined so as to be an inner pipe through which the pipe is inserted in the axial direction, it is said that the discharge pipe 2 and the return pipe 3 are combined in a state of being overlapped with each other as shown in FIG. The discharge pipe 2 corresponds to the discharge flow path described above, and the return pipe 3 corresponds to the return flow path.

If the hollow cross section has a curved shape such as a semi-cylindrical shape or a crescent shape, when blood passes through the discharge pipe 2 and the return pipe 3, it is easy to cause convection in the blood. There is an advantage that the pressure inside and inside the return pipe 3 can be easily dispersed, and the weak point in strength due to the internal pressure of the discharge pipe 2 and the return pipe 3 can be easily reduced.

"One of them becomes an outer pipe" means that the discharge pipe 2 becomes an outer pipe and the return pipe 3 becomes an inner pipe, and the return pipe 3 becomes an outer pipe and the discharge pipe 2 becomes an inner pipe. It means that there is a case, and it means that the other (inner pipe) inserts the inside of one (outer pipe). 1 and 3 show an example in which the discharge pipe 2 is the outer pipe and the return pipe 3 is the inner pipe. However, the outer pipe in FIG. 1 and the like is the return pipe 3, and the inner pipe is It may be the discharge pipe 2.

“Integrally (combined)” is shown in FIG. 11- (a) when, for example, the discharge pipe 2 and the return pipe 3 are overlapped and combined so as not to be separated from each other from the combined state. As described above, the unity is provided by some kind of holding material 4 such as an annular material surrounding the discharge pipe 2 and the return pipe 3, or a tubular material, which is circumscribed to the discharge pipe 2 and the return pipe 3 at the same time and holds them in a state of being overlapped with each other. Say to keep. When the discharge pipe 2 and the return pipe 3 are overlapped with each other, the discharge pipe 2 and the return pipe 3 do not necessarily have to be in contact with each other.

When the other (inner pipe) inserts the inside of either one (outer pipe) of the return pipe 3 and the discharge pipe 2, the pipe (inner pipe) on the inserted side is held by the pipe (outer pipe) on the inserted side. Therefore, since the integrity of the inner pipe and the outer pipe is ensured, the holding material 4 for preventing the separation of the discharge pipe 2 and the return pipe 3 in the combined state is not always required. However, in FIG. 1 and the like, the holding material 4 is attached to the outside of the blood vessel of the outer tube in order to ensure the stability of both in the inserted state of the inner tube (combination of the inner tube and the outer tube). "Outside the blood vessel" means "the side located outside the blood vessel" or "the side far from the blood vessel".

When the inner tube is inserted into the outer tube, as shown in FIG. 1, the inserted side tube (inner tube) protrudes from the end (end surface) of the inserted side tube (outer tube) on the blood vessel side. In some cases. In this case, the position of the end on the blood vessel side of the tube (inner tube) on the inserted side and the end on the blood vessel side of the tube (outer tube) on the inserted side are different, so that the blood in the blood vessel is taken in and discharged. Since the positions of the outflow hole 2a of the tube 2 and the inflow hole 3a of the return tube 3 for returning the purified blood into the blood vessel can be different, the freshly purified blood is discharged from the outflow hole 2a of the discharge tube 2. It becomes easy to avoid taking it into the pipe 2. When the indwelling needle 1 is used, the outflow hole 2a of the discharge pipe 2 to the inflow hole 3a of the return pipe 3 are inserted into the blood vessel.

When the inner tube penetrates the inside of the outer tube, the inner tube penetrates the outer end 22 facing the outside of the blood vessel at the root portion located outside the blood vessel of the outer tube as shown in FIG. At least a part of the outer end portion 22 of the inner tube is opened for insertion of the inner tube, and an opening 22a is formed. The outer end portion 22 is a wall outside the blood vessel of the transition portion 21 as a storage space described later, or a portion corresponding to the wall. "At least a part of the outer end portion 22 is opened" means that the opening 22a formed by the opening is not always located at the central portion of the outer end portion 22. As will be described later, since the inner needle 6 or the inner needle 6 and the inner tube are inserted into the opening 22a, the opening 22a is mainly circular, but the shape of the opening 22a is not necessarily circular. The outer end portion 22 corresponds to, for example, a part of the outer end portion of the blood vessel of the holding material 4 that holds the end portion on the root side of either the discharge pipe 2 and the return pipe 3, or both of them, which will be described later.

When the inner pipe is inserted into the outer pipe, the inner needle 6 and the inner pipe are inserted into the opening 22a, so that the opening 22a (outer end 22) is formed in the outer pipe as shown in FIGS. 3 and 6. NS. When the discharge pipe 2 and the return pipe 3 are overlapped with each other, the inner needle 6 is inserted through the opening 22a. Therefore, as shown in FIG. 11, the opening 22a (outer end 22) is the discharge pipe 2 and the return pipe 3. Formed in either.

As shown in FIG. 6- (a), an inner needle 6 for puncturing a blood vessel is also inserted into the opening 22a of the outer end 22 of the outer tube before the inner tube is inserted. In this relationship, the inside of the outer tube has a cross-sectional area through which the inner tube and the inner needle 6 can be inserted. This can be said to be "the inner diameter of the outer tube is larger than the outer diameter of the inner needle 6" in the case where the outer tube, the inner tube and the inner needle 6 have a cylindrical shape.

When the discharge pipe 2 and the return pipe 3 are superposed, there is no distinction between the outer pipe and the inner pipe, so that the inside of either the discharge pipe 2 or the return pipe 3 has a cross-sectional area through which the inner needle 6 can be inserted. At least a part of the outer end 22 of the tube on the side through which the inner needle 6 is inserted is opened to form an opening 22a. In claim 1, "either one of the discharge pipe and the return pipe has a cross-sectional area through which the inner needle can be inserted" refers to the outer pipe when the outer pipe and the inner pipe are distinguished. , When not distinguished, refers to either the discharge pipe 2 or the return pipe 3.

Whether the inner pipe is inserted through the outer pipe or the discharge pipe 2 and the return pipe 3 are overlapped with each other, the outer end of either the discharge pipe 2 or the return pipe 3 on which the inner needle 6 is inserted is inserted. A hemostatic valve 42 that prevents the outflow of blood existing inside either the discharge pipe 2 or the return pipe 3 from the outer end 22 to the outside of the blood vessel is arranged in close contact with the outer end face of the blood vessel 22. (Claim 1). Here, "one of the discharge pipe 2 and the return pipe 3" refers to an outer pipe when one of them inserts the inside of the other, and when one of them is superposed on each other, the side on which the inner needle 6 is inserted is inserted. Refers to a tube.

When the inner pipe (return pipe 3) is inserted into the outer pipe (discharge pipe 2) after the inner needle 6 is pulled out as shown in FIGS. 3 and 7, the inner pipe is opened in the opening 22a of the outer end 22. A hemostatic valve 42 is provided on the outer end face of the blood vessel of the outer end 22 for the purpose of preventing the outflow of blood existing in the transition portion 21 of the outer tube from the opening 22a when the inner tube is inserted. It is brought into close contact (claim 1). The hemostatic valve 42 also functions to prevent the outflow of blood from the opening 22a after the inner needle 6 is pulled out from the outer tube until the inner tube is inserted into the outer tube. Alternatively, it functions to prevent the outflow of blood from the opening 22a after the inner needle 6 is pulled out from either the discharge pipe 2 or the return pipe 3. In the case of the example shown in FIG. 11- (c), the notch 42a described later is closed, and in the case of the example shown in FIGS. 7- (b) to (e), the insertion hole through which the inner needle 6 is inserted. The 42c returns (contracts) to the state before the insertion of the inner needle 6 to prevent the outflow of blood.

In the portion of either the discharge pipe 2 or the return pipe 3 on the side through which the inner needle 6 is inserted, which is located outside the blood vessel, a discharge hole 2b for discharging blood to the outside of the discharge pipe 2 for purification is provided. A transition portion 21 is formed as a storage space that communicates with the return hole 3b that communicates or returns purified blood from outside the return tube 3. The transition portion 21 (storage space) is a space in which blood temporarily exists (stores), and corresponds to the branch point 98 of Patent Document 2.

On the other hand, since the inner needle 6 may penetrate the outer end 22 which is the wall outside the blood vessel of the transition portion 21 (storage space) or corresponds to the wall, the hemostasis attached to the outer end 22 is attached. The valve 42 is formed with a notch 42a as shown in FIGS. 5- (c), 8- (b), (c), and 11- (c) through which the inner needle 6 can penetrate, for example. Alternatively, as shown in FIGS. 7- (b) to 7- (e), the inner needle 6 can penetrate the hemostatic valve 42 and can be closed after the inner needle 6 is pulled out as described above. A hole having a length (insertion hole 42c) is formed. In this case, the hole (insertion hole 42c) allows the inner needle 6 to be inserted by expanding to the outer peripheral side of the hole when the inner needle 6 is inserted, and the inner needle 6 is inserted when the inner needle 6 is pulled out. It is closed by contracting (restoring) to the previous state.

When the discharge pipe 2 and the return pipe 3 are superposed, the hemostatic valve 42 is used as the inner needle 6 because it is necessary to prevent the blood existing in the transition portion 21 from flowing out from the opening 22a after the inner needle 6 is pulled out. The hemostatic valve 42 has, for example, a notch 42a as shown in FIGS. 5- (c) and 7- (b) to (e) so as to close the opening 22a after the inner needle 6 is pulled out while allowing the insertion of It is formed. The hemostatic valve 42 allows the inner needle 6 to be inserted when the inner needle 6 penetrates the opening 22a in this way, and secures liquidtightness with the outer peripheral surface of the inner pipe after the inner needle 6 is pulled out. Alternatively, it has the role of completely closing the opening 22a.

In claim 1, "the hemostatic valve 42 is arranged in close contact with the outer end surface of the blood vessel of the outer end 22" basically means that the hemostatic valve 42 is outside the blood vessel of the outer end 22 as shown in FIG. It means that it is attached to the outer end portion 22 in a state of being in close contact with the end surface (opposite side of the transition portion 21). FIGS. 1 to 10 show an example in which the discharge pipe 2 is an outer pipe. Therefore, the outer end 22 is formed in the discharge pipe 2, but if the return pipe 3 becomes an outer pipe, the return pipe 2 is restored. An outer end is formed on the tube 3.

As long as the hemostatic valve 42 is attached to the outer end 22 in a state of being in close contact with the outer end surface of the blood vessel of the outer end 22, the method of maintaining the attached state does not matter. The hemostatic valve 42 is thick as shown in FIG. 3, for example, between the discharge pipe 2 and the return pipe 3, or the fittings 31 and 61 connected to the outside of the blood vessel of the inner needle 6 and the end surface of the outer end portion 22. When the state of being sandwiched in the longitudinal direction and being attached to the outer end portion 22 is maintained (claim 2), the case where the inner pipe is inserted into the outer pipe and the case where the discharge pipe 2 and the return pipe 3 are overlapped with each other. Corresponds to any of. The connecting tools 31 and 61 are connected to the holding material 4 that holds the outer ends of either the discharge pipe 2 and the return pipe 3 or both blood vessels.

In this case, the hemostatic valve 42 is arranged outside the blood vessel of the hemostatic valve 42 as shown in FIGS. 3 and 6- (a), and is connected to the return tube 3 connected to the holding material 4 or the inner needle 6. It is sandwiched between the connector 61 and the holding material 4 and held and restrained. In the case of the example shown in FIG. 11, the hemostatic valve 42 is sandwiched between the outer end portion 22 constituting the transition portion 21 and the connecting tool 61 of the inner needle 6 and is restrained. The confirmation work of the hemostatic valve 42 is performed by separating the fittings 31 and 61 from the outer end portion 22.

In this case, when the inner pipe (return pipe 3) is inserted into the outer pipe (discharge pipe 2) while the indwelling needle 1 is in use after the inner needle 6 is pulled out as shown in FIGS. 3 and 6. For example, as shown in FIG. 7, the hemostatic valve 42 is in close contact with the outer end surface of the blood vessel of the outer end portion 22 and the outer peripheral surface of the inner tube, and the gap between the outer peripheral surface of the inner tube and the opening 22a is formed. A tubular (annular) or other sealing material (watertight material) made of an elastic material that prevents the generation is used. In this case, as shown in FIGS. 5- (c), 8- (b), and (c), an elastic material having a notch 42a such as a cross shape or a Y shape can also be used.

When the inner pipe is inserted into the outer pipe, that is, when either the return pipe 3 or the discharge pipe 2 is inserted as the inner pipe and the other inside as the outer pipe is inserted in the axial direction, the hemostatic valve 42 is shown in FIG. As shown in a), it may be formed in a tubular shape with a flange 42b that is in close contact with the end surface of the outer end 22 while being in close contact with the inner peripheral surface of the opening 22a of the outer end 22 (claim 3). In this case, both the inner tube and the inner needle 6 can be inserted into the inner peripheral surface of the hemostatic valve 42, that is, the inner peripheral surface of the insertion hole 42c, and can be in close contact with both outer peripheral surfaces (claim 3).

In this case, the hemostatic valve 42 is in close contact with the end surface of the outer end 22 on the surface of the flange 42b near the transition portion 21, and is in close contact with the inner peripheral surface of the opening 22a on the outer peripheral surface of the tubular portion other than the flange 42b. The inner peripheral surface (insertion hole 42c) of the tubular portion of the hemostatic valve 42 other than the flange 42b is in close contact with the outer peripheral surfaces of the inner needle 6 and the inner tube, respectively, and elastically deforms to the outer periphery of the center. Try to extend to the side.

In this case, when the inner needle 6 is pulled out and when the inner tube is pulled out, it returns (shrinks) to the center (axis) side as shown in FIGS. (Thick part) is blocked and prevents blood from flowing out. The insertion hole 42c has a certain length in the axial direction as described above in order to be in close contact with both the outer peripheral surfaces of the inner needle 6 and the inner tube having different outer diameters, and then FIG. 7- (b). )-(E), it is appropriate to form a conical shape in which the inner diameter gradually decreases from the outside of the blood vessel to the transition portion 21 side.

As shown in FIG. 11, after the inner needle 6 is pulled out from the discharge pipe 2 or the return pipe 3, the inner pipe is used in a state where the discharge pipe 2 and the return pipe 3 are separated, that is, in the state where the indwelling needle 1 is used. When there is no distinction between the outer tube and the outer tube, the hemostatic valve 42 needs to completely close the opening 22a after the inner needle 6 is pulled out. Therefore, the hemostatic valve 42 is shown in FIGS. 11- (c) and 11- (d). As described above, an elastic material in a form that closes after the inner needle 6 is pulled out is used.

In both the example shown in FIG. 3 and the example shown in FIG. 11, the hemostatic valve 42 is attached to the outer end face of the outer end 22 of the outer end 22 located outside the blood vessel of either the discharge pipe 2 or the return pipe 3. By being attached to the outer end 22 in a close contact state and being arranged at a position facing the surface of the outer end 22, the work of attaching the hemostatic valve 42 to the outer end 22 and the work of confirming the attached state are simple. Be made. In particular, since it is not necessary to use the reciprocating movement of the arm-shaped inserter for mounting the hemostatic valve 42, the structure of the indwelling needle including the hemostatic valve 42 is simplified in comparison with Patent Documents 1 to 4. , The work of attaching the hemostatic valve 42 is simplified, and it becomes easy to check the attached state of the hemostatic valve 42.

As described above, either the discharge pipe 2 or the return pipe 3 is placed on the outer end surface of the blood vessel of the outer end 22 on the side located outside the blood vessel of either the discharge pipe 2 or the return pipe 3 through which the inner needle 6 is inserted. The transition portion 21 of either the discharge pipe 2 or the return pipe 3 is brought into close contact with the hemostatic valve 42 that allows the insertion of the inner needle 6 while preventing the outflow of blood existing inside one of the blood vessels to the outside of the blood vessel. The blood present inside is prevented from flowing out of the blood vessel from the outer end 22.

The outer end portion 22 is located outside the blood vessel of the transition portion 21 located outside the blood of either the discharge pipe 2 or the return pipe 3, and is a wall surface exposed to the outside when the inner needle 6 is not inserted, so that hemostasis is stopped. The installation (mounting) work of the valve 42 can be made extremely easy and reliable. In particular, when the hemostatic valve 42 is a hemostatic valve that overlaps the surface of the outer end 22 on the outer side of the blood vessel, it is not necessary to install the outer end 22 into the opening 22a, and the outer end 22 is simply attached to the outer end 22. Installation work is simplified because installation is completed simply by stacking.

In claim 1, "an outflow hole is formed in a portion of the discharge pipe located inside the blood vessel to allow blood to flow out of the blood vessel" means that the blood outflow occurs in any part of the section of the discharge pipe 2 located inside the blood vessel. It means that the outflow hole 2a is formed, and includes the end face of the discharge pipe 2 near the axial blood vessel. Since it is "any part of the section located in the blood vessel", if it is formed on a section other than one end face of the discharge pipe 2, an outflow hole 2a may be formed on the peripheral surface of the section other than the end face. be. In that case, the end face of the discharge pipe 2 near the blood vessel is closed.

"A discharge hole is formed in a portion of the discharge pipe located outside the blood vessel to discharge blood to the outside of the discharge pipe." It means that 2b is formed, and includes an axial end surface (outer end portion 22) of the discharge pipe 2. Since it is "any part of the section located outside the blood vessel", if it is formed on a section other than the other end face of the discharge pipe 2, the discharge hole 2b may be formed on the peripheral surface of the section other than the end face. be. When the inner needle 6 penetrates the opening 22a of the outer end portion 22 as described above, the discharge hole 2b is formed in a section excluding the end face as shown in FIG. 1 and the like.

Similarly, "an inflow hole for allowing blood to flow into the blood vessel is formed in a portion of the return tube located in the blood vessel" means that the purified blood is formed in any part of the section of the return tube 3 located in the blood vessel. It means that the inflow hole 3a for inflow is formed, and there are cases where it is formed on the end face (outer end portion 22) of the return pipe 3 and cases where it is formed in a section other than the end face. "A return hole for returning blood from outside the return tube is formed in a portion located outside the blood vessel of the return tube" means that a blood vessel of purified blood is formed in any part of the section located outside the blood vessel of the return tube 3. It means that a return hole 3b for returning to the inside is formed, and there are cases where it is formed on the end face of the return tube 3 and cases where it is formed in a section other than the end face.

The indwelling needle 1 composed of the discharge pipe 2 and the return pipe 3 is inside as shown in FIG. 6 when either the return pipe 3 or the discharge pipe 2 inserts the inside of the other as shown in FIG. The tip of the inner needle 6 inserted into the outer tube in which the tube has been pulled out is inserted into the blood vessel through the perforation of the blood vessel formed by puncturing the blood vessel. When the return pipe 3 and the discharge pipe 2 are superposed on each other, the inner needle 6 is inserted into one of the pipes as shown in FIG. The indwelling needle 1 is inserted into the blood vessel until the outflow hole 2a of the discharge pipe 2 and the inflow hole 3a of the return pipe 3 enter. After inserting the indwelling needle 1 into the blood vessel, the inner needle 6 is pulled out from the root side of the inner tube.

As shown in FIG. 4- (a), a transfer pipe 5 for transferring blood taken into the discharge pipe 2 to a dialysis machine (filtration device) is connected to the discharge hole 2b of the discharge pipe 2, and the return pipe 3 is connected. A supply pipe 7 for returning purified blood to a blood vessel via a dialysis machine is connected to the return hole 3b. The inside of the transfer pipe 5 communicates with the inside of the discharge pipe 2, and the inside of the supply pipe 7 communicates with the inside of the return pipe 3. As described above, since the transition portion 21 is formed in the portion of either the discharge pipe 2 or the return pipe 3 on the side through which the inner needle 6 is inserted, which is located outside the blood vessel, the inside of the transfer pipe 5 is formed. , Or the inside of the supply pipe 7 communicates with the transition portion 21.

The blood in the blood vessel is sucked into the discharge tube 2 from the outflow hole 2a by the suction force of the pump connected between the transfer tube 5 and the dialysis device, and is sent to the dialysis device as it is via the transfer tube 5. The purified blood that has passed through the dialysis apparatus is returned into the blood vessel from the inflow hole 3a of the return pipe 3 through the supply pipe 7 by the discharge force of the pump.

An opening is formed at the outer end of either the discharge tube or the return tube through which the inner needle is inserted, which is located outside the blood vessel, and either the discharge tube or the return tube is formed at the outer end surface of the blood vessel at the outer end. Since the hemostatic valve that allows the insertion of the internal needle is in close contact with the blood vessel that is present inside the blood vessel while preventing the blood from flowing out of the blood vessel, the blood existing in the transition part of either the discharge tube or the return tube is present. It is possible to easily and reliably install (attach) the hemostatic valve while preventing the blood vessel from flowing out from the outer end.

(A) shows an example of manufacturing an indwelling needle in which the discharge pipe and the return pipe are combined with the return pipe inserted inside the discharge pipe when the discharge pipe is the outer pipe and the return pipe is the inner pipe. A perspective view, (b) is a sectional view taken along line xx of (a). (A) is a perspective view showing the discharge pipe shown in FIG. 1, and (b) is a perspective view showing the return pipe shown in FIG. It is a vertical cross-sectional view which showed the state of cutting in the vertical plane including the axis of the specific indwelling needle of the form shown in FIG. (A) is a vertical cross-sectional view showing the discharge pipe of FIG. 3, and (b) is a vertical cross-sectional view showing the return pipe of FIG. (A) is a sectional view taken along line xx of FIG. 3, (b) is a sectional view taken along line yy of FIG. 3, and (c) is a sectional view taken along line zz of FIG. (A) is a vertical cross-sectional view showing a state in which an inner needle for puncture is inserted into the discharge pipe with the return pipe removed from the discharge pipe among the indwelling needles shown in FIG. 3, and (b) is (a). X-ray arrow view, (c) is a vertical cross-sectional view showing the discharge pipe in (a), and (d) is a vertical cross-sectional view showing the inner needle in (a). (A) is a vertical cross-sectional view showing an example in which a tubular sealing material is used as a hemostatic valve for closing the opening at the outer end of the outer tube, and (b) is a hemostatic valve used in (a). (C) is a vertical cross-sectional view passing through the axis of (b), (d) is a perspective view showing a modified example of (b), and (e) is an axis of (d). It is a vertical cross-sectional view through. (A) is a perspective view showing a state in which a hemostatic valve is arranged on the end surface of the connecting portion of the holding material as a specific example of the holding material which is the connecting portion of the discharge pipe to the transfer pipe shown in FIG. 2- (a). b) is a perspective view showing a state in which the cap is connected to the surface side of the hemostatic valve of (a), and (c) is a side view of (b). FIG. 5 is a perspective view showing a state in which a connecting pipe for connecting a supply pipe is connected to the holding material shown in FIG. (A) is a perspective view showing a combination state with a discharge pipe which is an outer pipe when the return pipe which is an inner pipe has a crescent-shaped (U-shaped) cross-sectional shape, and (b) is a return of (a). The perspective view which showed the pipe, (c) is the perspective view which showed the discharge pipe of (a). (A) shows an example of a combination in which the return pipe and the discharge pipe are overlapped with each other, and an example in which a hemostatic valve having a disk shape or the like shown in (c) is inserted through the opening at the outer end of the transition portion. Vertical sectional view, (b) is a sectional view taken along line xx of (a), (c) is a perspective view showing an example of the shape of the hemostatic valve used in (a), and (d) is (c). It is a side view of.

FIG. 1 shows a hollow cross-section discharge tube 2 that is inserted into a blood vessel and discharges blood in the blood vessel from the blood vessel to the outside of the blood vessel, and a discharge tube 2 that is inserted into the blood vessel and integrally combined with the discharge tube 2 and once discharged from the blood vessel. An example of manufacturing (configuration) of an indwelling needle 1 provided with a return tube 3 having a hollow cross section for returning the blood to the inside of a blood vessel is shown. 2 (a) and 2 (b) show a discharge pipe 2 which is an outer pipe and a return pipe 3 which is an inner pipe which is inserted into the outer pipe, respectively, in the production example shown in FIG.

1 to 10 show an example in which the discharge pipe 2 is an outer pipe and the return pipe 3 is an inner pipe, but the discharge pipe 2 becomes an inner pipe and the return pipe 3 becomes an outer pipe. There is also. Hereinafter, an example will be described in which the discharge pipe 2 is an outer pipe and the return pipe 3 is an inner pipe. In the drawing, there is also an example in which the discharge pipe 2 (outer pipe) has a circular cross-sectional shape and the return pipe 3 (inner pipe) has a semi-circular shape or a crescent-shaped (U-shaped) cross-sectional shape as shown in FIG. However, the cross-sectional shapes of the discharge pipe 2 (outer pipe) and the return pipe 3 (inner pipe) are not limited as long as they have a hollow cross section. The materials of the discharge pipe 2 and the return pipe 3 are not particularly limited, but are mainly manufactured from synthetic resin or the like. For example, fluororesin, polyamide resin and the like.

As shown in FIGS. 1 and 2, the cross-sectional area perpendicular to the axis of the inner tube is halved to the cross-sectional area perpendicular to the axis of the outer tube, as in the case where the inner tube has a semi-cylindrical shape and the outer tube has a cylindrical shape. In the case of a combination of such cross-sectional shapes, the amount of blood taken in from the outflow hole 2a of the discharge pipe 2 (blood flow velocity) and the blood discharged from the inflow hole 3a of the return pipe 3 The amount per unit time (blood flow velocity) can be made equal. Therefore, the suction force of the pump when sucking blood from the outflow hole 2a into the discharge pipe 2 and the discharge force of the pump when returning the blood from the inflow hole 3a of the return pipe 3 into the blood vessel can be made equal.

When the inner tube is formed into a semi-cylindrical shape, if the outer tube is formed in a cylindrical shape through which the inner tube is inserted so as to fit inside the outer tube, the cross section of the main body portion (cylindrical portion) of the outer tube is formed. It is possible to combine the inner tube with the outer tube regardless of the form or material other than the shape. That is, if the main body of the return pipe 3 alone or the discharge pipe 2 alone, which is the inner pipe, is formed in a semi-cylindrical shape, it can be combined with an outer pipe of any shape or material whose main body is cylindrical. Is.

3 and 4 show a specific vertical cross section of the indwelling needle 1 in the form shown in FIGS. 1 and 2. FIG. 3 shows a combined state of the discharge pipe 2 and the return pipe 3, and FIG. 4 shows a single unit of the discharge pipe 2 and the return pipe 3. As shown here, an outflow hole 2a for allowing blood to flow out of the blood vessel is formed in a portion of the discharge pipe 2 located inside the blood vessel, and blood is discharged to the outside of the discharge pipe 2 in a portion of the discharge pipe 2 located outside the blood vessel. A discharge hole 2b for discharging is formed. An inflow hole 3a for allowing blood to flow into the blood vessel is formed in a portion of the return tube 3 located inside the blood vessel, and a return hole 3b for returning blood from outside the return tube 3 in a portion of the return tube 3 located outside the blood vessel. Is formed.

FIG. 1 and the like show an example in which the outflow hole 2a is formed on the end face of the discharge pipe 2 on the axial blood vessel side, but the outflow hole 2a may be formed on the peripheral surface of a section other than the end face. In that case, the end face of the discharge pipe 2 on the blood vessel side is closed in order to prevent the blood taken in from the outflow hole 2a from flowing out from the end face. The outflow hole 2a communicates with the space inside the discharge pipe 2.

In the example shown in FIG. 1, the section including the end of the return pipe 3 on the blood vessel side protrudes from the end face of the discharge pipe 2 on the blood vessel side, so that the axial end face of the discharge pipe 2 which is the outflow hole 2a is complete. Even if it is open to the outside, the blood flowing in the discharge pipe 2 and the blood flowing in the return pipe 3 do not intersect, but the outflow hole 2a may be formed in a part of the end face of the discharge pipe 2.

In the case of the example shown in FIG. 1, at least a section from the outflow hole 2a of the discharge pipe 2 to the inflow hole 3a of the return pipe 3 is inserted into the blood vessel. The cross-sectional shape of the inflow hole 3a and the outflow hole 2a inserted into the blood vessel does not matter. The inflow hole 3a and the outflow hole 2a are formed in a shape cut by a flat surface or a curved surface that intersects the discharge pipe 2 and the return pipe 3 in the axial direction as shown by the inner needle 6 shown in FIGS. It may be, but it is not always necessary if the outer diameter itself is small.

As shown in FIGS. 3 and 4- (a), the discharge hole 2b is an end portion of the discharge pipe 2 on the side located outside the blood vessel, and is formed in a transition portion 21 which is a storage space for temporarily storing blood. It is formed so as to communicate with the space inside the discharge pipe 2. A transfer pipe 5 for transferring the blood taken into the discharge pipe 2 to the dialysis machine (filtration device) is connected to the discharge hole 2b.

In order to prevent the transfer pipe 5 from being separated from the discharge pipe 2, the transfer pipe 5 is connected to the discharge hole 2b as shown in the transition portion 21 which is the forming portion of the discharge hole 2b of the discharge pipe 2. It is appropriate that the tubular holding material 4 for holding the pipe in the discharge pipe 2 is attached in a form circumscribing the transition portion 21. The holding material 4 has a role of holding the outer end of the blood vessel of the discharge pipe 2, but the return pipe 3 (inner pipe) that inserts the inside of the discharge pipe 2 (outer pipe) or the inner needle 6 for puncturing the blood vessel. Is also used to connect to the discharge pipe 2. The transfer tube 5 is made of, for example, polyurethane, polyvinyl chloride, or the like.

In the case of the illustrated example in which the discharge pipe 2 is an outer pipe, the holding material 4 may be in any form as long as it holds the transfer pipe 5 and has a shape that enables the connection between the return pipe 3 and the inner needle 6. In FIG. 3 and the like, the holding material 4 is composed of a holding portion 4a that surrounds the transition portion 21 in which the discharge hole 2b is formed from the outer peripheral side, and an outer skin 4b that covers and protects the holding portion 4a. The material of the holding material 4 is not limited, but is manufactured from, for example, polyamide resin, polyoxymethylene (polyacetal resin), polypropylene, or the like.

In the examples of FIGS. 3 and 4, the holding portion 4a is attached around the transition portion 21 by assembling, for example, a block previously divided into a plurality of molded blocks so as to surround the portion of the transition portion 21. In this example, the outer skin 4b has a role of directly holding the discharge pipe 2. In this example, the cross-sectional area perpendicular to the axis of the formed portion of the transition portion 21 is expanded from the cross-sectional area of the other sections so that the blood taken into the discharge pipe 2 can be temporarily stored inside the transition portion 21. However, the volume of the transition portion 21 is increased, but it is not always necessary.

The connecting tool shown in FIG. 4- (b) is attached (connected) to the outer peripheral side of the return tube 3 near the end surface of the holding material 4 (holding portion 4a) on the outer side of the blood vessel (opposite side of the blood vessel). Both the 31 and the connector 61 shown in FIG. 6- (d) attached (connected) to the outer peripheral side of the inner needle 6 on the outer peripheral side of the blood vessel are of a male screw or the like for being separably connected by screwing or the like. The connecting portion 41 is formed. When the connecting portion 41 is a male screw, a female screw is formed on the inner peripheral surface of the connecting tool 31 and the connecting tool 61 on the connecting portion 41 side.

FIG. 6- (a) shows a state in which the inner needle 6 is inserted into the discharge pipe 2 as the outer pipe before the return pipe 3 as the inner pipe is inserted. In this example, as shown in FIGS. 6- (a) and 6- (d), the holder 62 arranged on the outside of the blood vessel of the connector 61 of the inner needle 6 holds the inner needle 6 on the connector 61, and the holder 62 The cap 63 arranged on the blood vessel side closes the hole on the root side of the inner needle 6. In this example, if the cap 63 is removed, blood can be collected through the inner needle 6.

Further, on the outer circumference of the holding material 4, when the connecting portion 41 and the connecting tool 31 shown in FIG. 1, for example, are connected to the holding material 4 by rotation around an axis, the connecting tool 31 is not easily separated from the holding material 4. As a result, the protrusion 41a is formed. The connector 61 shown in FIG. 6 is also connected to the connecting portion 41. Alternatively, the connecting portion 81 formed on the holding material 4 side of the connecting pipe 8 shown in FIG. 9 to which the supply pipe 7 is connected is also connected to the connecting portion 41. On the other hand, grooves 31a, 61a, 81a in which the protrusion 41a enters are formed in the circumferential direction at a position corresponding to the protrusion 41a of the connecting tool 31, the connecting tool 61, or the connecting portion 81. The connector 31 is made of the same material (synthetic resin) as the holding material 4. Like the transfer pipe 5, the supply pipe 7 is made of, for example, polyurethane, polyvinyl chloride, or the like.

As shown in FIG. 2- (b), the grooves 31a, 61a, 81a are continuously formed with the grooves 31b, 61b, 81b in the axial direction of the connector 61. When the connector 31, 61, or the connector 81 is connected to the connector 41, the protrusion 41a enters the groove 31b, 61b, 81b in the axial direction, and the connector 31, 61, or the connector 81 rotates about the axis as it is. As a result, the protrusion 41a enters the grooves 31a, 61a, 81a in the circumferential direction, and the connecting tool 31, 61, or the connecting portion 81 is prevented from coming off from the connecting portion 41.

A part of the outer end portion 22 that constitutes the above-mentioned transition portion 21 and forms the end surface on the connecting tool 31 and 61 side (opposite side of the blood vessel) of the holding material 4 is shown in FIGS. 4- (a) and 6- (c). ), When the return pipe 3 or the inner needle 6 is connected, the return pipe 3 or the inner needle 6 is opened so as to be inserted, and an opening 22a is formed in the outer end portion 22. The return tube 3 or the inner needle 6 inserts the opening 22a and the transition portion 21. The shape of the opening 22a is arbitrary and is not limited to a circular shape.

Since the opening 22a is formed in the outer end portion 22, when the return pipe 3 or the inner needle 6 is connected to the holding material 4 (discharge pipe 2), the return pipe 3 or the inner needle 6 is taken into the discharge pipe 2 and is taken into the transition portion 21. A hemostatic valve 42 is arranged in the end face and the opening 22a of the holding material 4 (outer end 22) so that the blood existing in the holding material 4 does not flow out from the end face of the holding material 4 to the outside of the outer end 22. The hemostatic valve 42 closes the end face (opening 22a of the outer end 22) of the holding material 4 while the return tube 3 or the inner needle 6 is inserted and after the inner needle 6 is pulled out. The hemostatic valve 42 is arranged in close contact with the outer end face of the blood vessel of the outer end 22.

As in the example shown in FIGS. 1 to 6, when the inner needle 6 is inserting the opening 22a of the holding material 4 (discharge pipe 2), the hemostatic valve 42 allows the inner needle 6 to be inserted, and the inner needle 6 is inserted. When the return tube 3 is inserted through the opening 22a after being pulled out, the hemostatic valve 42 is directed toward the outer peripheral side from the position where the inner needle 6 or the return tube 3 is inserted, for example, as shown in FIG. 5- (c). For example, a plate (disk) -shaped elastic body (sealing material) having a notch 42a is used. When the inner needle 6 or the like inserts the notch 42a into the notch 42a portion of the hemostatic valve 42, the peripheral portion of the notch 42a (the portion other than the notch 42a) is the inner needle 6 or the like while being in close contact with the outer peripheral surface of the inner needle 6 or the like. When the inner needle 6 or the like is pulled out, it returns to the original state and becomes a completely closed state.

However, even in the case of the examples shown in FIGS. 1 to 6, as the hemostatic valve 42, for example, FIGS. 7- (b) and (d) as shown in FIGS. 3, 4- (a) and 6- (c). ), It is also possible to use a sealing material having a notch 42a in the thickness direction of the plate-shaped elastic body without the flange 42b. In that case, since the inner needle 6 and the return tube 3 (inner tube) are inserted into the insertion hole 42c of the hemostatic valve 42, the notch 42a is large enough so that the outer peripheral surface of the inner needle 6 and the outer peripheral surface of the return tube 3 are in close contact with each other. It is set (adjusted). When the inner needle 6 and the return tube 3 (inner tube) are pulled out from the notch 42a, the notch 42a is closed and the hemostatic valve 42 prevents the outflow of blood in the transition portion 21.

It is appropriate that the hemostatic valve 42 is formed in a stepped shape on the transition portion 21 side so as to fit into the groove formed in the outer end portion 22 as shown in FIGS. 3 and 4- (a). be. The hemostatic valve 42 may be adhered to the groove in order to increase the stability of the outer end 22 in the groove when it is disengaged.

When the inner needle 6 inserts the opening 22a of the holding material 4 as shown in FIG. 6, and the return pipe 3 (inner pipe) inserts the opening 22a after the inner needle 6 is removed as shown in FIG. 3, it is indwelled. Since the return tube 3 is inserted through the hemostatic valve 42 in the state of using the needle 1, it is sufficient that the hemostatic valve 42 is in close contact with the outer peripheral surface of the return tube 3 and the outflow of blood from the outer peripheral surface of the return tube 3 can be prevented. .. Therefore, for the hemostatic valve 42, it is possible to use a tubular sealing material with a flange 42b as shown in FIGS. 7- (b) and 7- (d), which can be in close contact with the outer peripheral surface of the return pipe 3. In this case, as shown in FIG. 7- (a), for example, the hemostatic valve 42 has a tubular portion other than the flange 42b while the surface of the flange 42b on the holding material 4 side is in close contact with the outer end surface of the blood vessel of the outer end portion 22. The outer peripheral surface is attached to the outer end portion 22 (holding material 4) in a state of being in close contact with the inner peripheral surface of the opening 22a. The contact surface of the hemostatic valve 42 to the outer end 22 may be adhered.

In FIGS. 7- (b) to 7- (e), the inner peripheral surface of the hemostatic valve 42 forming the insertion hole 42c through which the inner needle 6 and the return tube 3 (inner tube) are inserted is formed in an axially conical shape. Even when the outer diameter of the inner needle 6 and the outer diameter of the return pipe 3 are different, it is possible to maintain a close contact state with the outer peripheral surface of any of the pipes. The difference between the outer diameter of the inner needle 6 and the outer diameter of the return pipe 3 can be dealt with by forming the inner peripheral surface forming the insertion hole 42c into a stepped shape or an uneven (bellows) shape. Is. Regardless of the shape of the insertion hole 42c, when the inner needle 6 is pulled out from the insertion hole 42c, or when the return tube 3 (inner tube) is pulled out, the plate of the tubular portion at least closer to the transition portion 21. By closing the shaped portion (thick portion), the outflow of blood in the transition portion 21 is prevented.

In the examples shown in FIGS. 7- (b) to 7- (e), the insertion hole 42a expands in the direction orthogonal to the axial direction when the inner needle 6 is inserted and when the return pipe 3 (inner pipe) is inserted, so that the inner needle 6 is inserted. The effect of preventing blood outflow is high because the state of being in close contact with the outer peripheral surface of the return tube 3 is maintained and the return tube 3 is not turned over as in the example shown in FIG. 11- (c).

In FIGS. 7- (d) and 7- (e), in particular, when the main body portion other than the flange 42b is elastically deformed to expand toward the outer peripheral side with respect to the portion closer to the flange 42b, the axial tip portion of the main body portion is inside the transition portion 21. An example is shown in which the outer peripheral portion is also formed into a truncated cone shape along the conical shape of the insertion hole 42c so that deformation is not hindered by contact with any of the portions. In this case, since the thickness (thickness) of the main body portion becomes uniform or substantially uniform in the axial direction, there is an advantage that expansion (elastic) deformation is likely to occur in any portion in the axial direction. In the examples of FIGS. 7- (d) and 7- (e), the outer peripheral surface of the main body portion near the flange 42b is in close contact with the inner peripheral surface of the opening 22a of the outer end portion 22.

8- (a) to (c) show the case where the connecting portion 41 for connecting (connecting) with the connecting tool 31 (61) is formed on the outer peripheral portion of the holding material 4 on the connecting tool 31 (61) side. An example is shown. The connecting portion 41 is formed on the outer peripheral portion of the outer end portion 22 of the transition portion 21. FIGS. 8-(a) to (c) show a state in which the hemostatic valve 42 having a notch 42a as shown in FIG. 11- (c) is in close contact with the end surface of the connecting portion 41 on the connecting tool 31 (61) side. ing. In FIG. 8, a cap 43 that covers the outer peripheral portion of the hemostatic valve 42 is arranged on the surface side of the hemostatic valve 42 to protect the hemostatic valve 42 from being in close contact with the connecting portion 41. The cap 43 is connected to the connecting portion 41 by, for example, screwing or fitting. (A) shows a state in which an opening for inserting the return pipe 3 (inner pipe) is formed in the central portion of the cap 43 or the like.

In FIG. 11- (c), the insertion hole 42c is formed in a conical shape in which the inner diameter gradually decreases from the outside of the blood vessel to the transition portion 21 side, and the insertion hole 42c is formed on the transition portion 21 side in the axial direction of the insertion hole 42c. A thick plate-shaped portion is formed, and a notch 42a is made in the plate-shaped portion, but the plate-shaped portion and the notch 42a are not always necessary. Since the insertion hole 42c is formed so as to penetrate at least in the axial direction of the hemostatic valve 42, the inner needle 6 and the inner tube can be inserted (penetrated) into the insertion hole 42c when the inner needle 6 and the inner tube are inserted. The form of the hemostatic valve 42 does not matter as long as the transition portion 21 side of the insertion hole 42c can be completely closed when the inner needle 6 or the inner tube is not inserted into the hole 42c.

FIG. 9 shows a state in which the connecting pipe 8 for connecting the supply pipe 7 is connected to the connecting portion 41 of the holding material 4 shown in FIG. In this example, the above-mentioned connecting portion 81 having grooves 81a and 81b connected to the connecting portion 41 is integrated with the holding member 4 side of the connecting pipe 8. The supply pipe 7 shown in FIG. 1 and the like is connected to the end of the connecting pipe 8 on the open side (opposite side of the holding material 4). Here, an example is shown in which the return pipe 3 as an inner pipe is connected to the connecting portion 81 (connecting pipe 8).

FIG. 10- (a) shows an example of combination with the discharge pipe 2 which is an outer pipe when the cross-sectional shape of the return pipe 3 which is the inner pipe is formed into a crescent shape (U-shape). (B) and (c) show a single unit of the return pipe 3 and the discharge pipe 2, respectively. In this example, since the entire inner peripheral surfaces of the discharge pipe 2 and the return pipe 3 are curved surfaces, it is easy for the blood moving in the discharge pipe 2 and the return pipe 3 to flow smoothly while causing convection inside each of them. Become.

11- (a) and 11- (b) show an example of a combination in which the discharge pipe 2 and the return pipe 3 are superposed on each other. In this example, the inner needle 6 is inserted into either the return pipe 3 or the discharge pipe 2, and after the inner needle 6 forms a perforation in the blood vessel, the inner needle 6 is pulled out. In FIG. 11, the inner needle 6 is inserted through the return pipe 3, but the inner needle 6 may be inserted through the discharge pipe 2. In the example shown in FIG. 11- (a), since the transition portion 21 is formed at a position communicating with the return hole 3b because the inner needle 6 is inserted into the return pipe 3, the connector 61 of the inner needle 6 is formed. Is screwed into the outer peripheral portion of the outer end portion 22 constituting the transition portion 21. When the inner needle 6 passes through the discharge pipe 2, the transition portion 21 is formed at a position communicating with the discharge hole 2b of the discharge pipe 2, and the connector 61 is attached to the outer end portion 22 constituting the transition portion 21. Be connected.

Of the return pipe 3 and the discharge pipe 2, an opening 22a through which the inner needle 6 is inserted is formed at the outer end 22 on the side through which the inner needle 6 is inserted. In this example, after the inner needle 6 is pulled out, the opening 22a needs to be closed by the hemostatic valve 42 in order to prevent the blood in the transition portion 21 facing the outer end 22 from flowing out from the opening 22a. In this relationship, in the example of FIG. 11- (a), a disc-shaped hemostatic valve in which a notch 42a is made from the central portion as shown in (c) and (d) on the end surface of the outer end portion 22 on the surface side. 42 is used. Since the outer shape of the hemostatic valve follows the shape of the opening 22a or the shape of the outer end portion 22, it is not limited to the circular shape. The surface of the hemostatic valve 42 on the transition portion 21 side shown in FIG. 11- (c) is the transition portion 21 as shown in (d) except for the outer peripheral portion so that the surface can be fitted into the groove formed in the outer end portion 22. It protrudes to the side.

In this case, the hemostatic valve 42 is fixed to the surface side of the outer end portion 22 by adhesion, fitting, or the like so as to close the opening 22a formed in the outer end portion 22 when the inner needle 6 is absent, and the inner needle 6 is fixed. When not, the part other than the notch 42a is completely closed. The wall thickness (plate thickness) of the hemostatic valve 42 should be large in order to enhance the safety of preventing the outflow of blood in the transition portion 21 from the opening 22a when the portion other than the notch 42a is closed.

When the inner needle 6 is inserted into the return tube 3 from the surface side of the hemostatic valve 42 into the notch 42a, the peripheral portion of the notch 42a enters the opening 22a and allows the inner needle 6 to be inserted into the opening 22a. When the inner needle 6 is pulled out, the peripheral portion of the notch 42a returns to the state shown in FIG. 11- (c), completely closes the opening 22a, and prevents the outflow of blood in the transition portion 21.

1 …… Indwelling needle,
2 ... Discharge pipe, 2a ... Outflow hole, 2b ... Discharge hole, 21 ... Transition part (storage space), 22 ... Outer end, 22a ... Opening,
3 ... Return pipe, 3a ... Inflow hole, 3b ... Return hole, 31 ... Connector, 31a ... Groove, 31b ... Groove,
4 ... Holding material, 4a ... Holding part, 4b ... Outer skin, 41 ... Connection part, 41a ... Protrusion, 42 ... Hemostasis valve, 42a ... Notch, 42b ... Flange, 42c ... Insertion hole, 43 …… Cap,
5 …… Transfer pipe,
6 ... Inner needle, 61 ... Connector, 61a ... Groove, 61b ... Groove, 62 ... Holder, 63 ... Cap,
7 …… Supply pipe,
8 ... Connecting pipe, 81 ... Connecting part, 81a ... Groove, 81b ... Groove.

Claims (2)

A hollow cross-section drainage tube that is inserted into a blood vessel and drains blood in the blood vessel from the blood vessel to the outside of the blood vessel, and a drainage tube that is inserted into the blood vessel and integrally combined with the drainage tube, and once from the blood vessel. A return tube having a hollow cross section for returning the discharged blood into the blood vessel is provided.
An outflow hole for discharging blood to the outside of the blood vessel is formed in a portion of the discharge pipe located inside the blood vessel, and a discharge hole for discharging blood to the outside of the discharge pipe is formed in a portion of the discharge pipe located outside the blood vessel. Formed,
An inflow hole for allowing blood to flow into the blood vessel is formed in a portion of the return tube located inside the blood vessel, and a return hole for returning blood from outside the return tube is formed in a portion of the return tube located outside the blood vessel. Formed,
The inside of either the discharge pipe or the return pipe has a cross-sectional area through which the inner needle that punctures the blood vessel can be inserted, and the discharge pipe or the return pipe through which the inner needle is inserted is said to have a cross-sectional area. An opening is formed at the outer end portion located on the outer side of the blood vessel, and the blood existing inside either the discharge pipe or the return pipe is formed on the outer end surface of the blood vessel at the outer end portion from the outer end portion. The hemostatic valve that allows the insertion of the inner needle is arranged in close contact with the blood vessel while preventing the outflow of the blood vessel .
One of the return pipe and the discharge pipe serves as an inner pipe, and the inside of the other as an outer pipe is inserted in the axial direction.
An indwelling needle characterized in that the hollow cross section of the inner tube is semicircular. A hollow cross-section drainage tube that is inserted into a blood vessel and drains blood in the blood vessel from the blood vessel to the outside of the blood vessel, and a drainage tube that is inserted into the blood vessel and integrally combined with the drainage tube, and once from the blood vessel. A return tube having a hollow cross section for returning the discharged blood into the blood vessel is provided.
An outflow hole for discharging blood to the outside of the blood vessel is formed in a portion of the discharge pipe located inside the blood vessel, and a discharge hole for discharging blood to the outside of the discharge pipe is formed in a portion of the discharge pipe located outside the blood vessel. Formed,
An inflow hole for allowing blood to flow into the blood vessel is formed in a portion of the return tube located inside the blood vessel, and a return hole for returning blood from outside the return tube is formed in a portion of the return tube located outside the blood vessel. Formed,
The inside of either the discharge pipe or the return pipe has a cross-sectional area through which the inner needle that punctures the blood vessel can be inserted, and the discharge pipe or the return pipe through which the inner needle is inserted is said to have a cross-sectional area. An opening is formed at the outer end portion located on the outer side of the blood vessel, and the blood existing inside either the discharge pipe or the return pipe is formed on the outer end surface of the blood vessel at the outer end portion from the outer end portion. The hemostatic valve that allows the insertion of the inner needle is arranged in close contact with the blood vessel while preventing the outflow of the blood vessel.
One of the return pipe and the discharge pipe serves as an inner pipe, and the inside of the other as an outer pipe is inserted in the axial direction.
An indwelling needle having a crescent-shaped or U-shaped hollow cross section of the inner tube.

Images