Shape holding device

Abstract

The present disclosure is a shape holding device (10) that prevents occlusion of the distal end of a catheter body (14). This shape holding device (10) comprises: a tube (40) in which a distal end region including at least an inflow port (42) is harder than the distal end part of a catheter body (14); and a support member (50) that has a fitting part (56) that can be fitted to a catheter hub (16) and communicates with the catheter hub (16) in a state of being fitted to the catheter hub (16), the support member (50) supporting the tube (40) so as to be displaceable with respect to the fitting part (56).

Description

Shape retention device

[0001] The present invention relates to a shape-retaining device that retains the shape of the tip of a catheter that is placed in a blood vessel.

[0002] The catheter assembly of Japanese Patent No. 3958956 includes a catheter body with an open tip, a catheter hub connected to the proximal end of the catheter body, and an inner needle disposed inside the catheter.

[0003] Patent No. 3958956

[0004] In the catheter assembly disclosed in Japanese Patent No. 3958956, after the tip of the catheter body is inserted into a blood vessel and the inner needle is removed, a suction device is attached to the catheter hub and blood is aspirated using the suction device. At this time, negative pressure is generated within the catheter hub and catheter body due to suction by the suction device, and the negative pressure can cause the tip of the catheter body to elastically deform, collapse, and become blocked. Blockage of the catheter tip makes it impossible to aspirate blood, making it impossible to accurately determine whether the catheter tip is inserted into the blood vessel.

[0005] The present invention aims to solve the above-mentioned problems.

[0006] (1) An aspect of the present invention is a shape-retaining device that is connected to a catheter member that includes a catheter body to be placed in a blood vessel and a catheter hub fixed to the base end of the catheter body, and that prevents occlusion of the tip end of the catheter body, and that has an inlet for introducing blood, an outlet for discharging blood, and a lumen that communicates with the inlet and the outlet, and that has a tip end region including at least the inlet that is harder than the tip end of the catheter body and that can be fitted into the catheter hub, and that has a shape-retaining device that can be fitted into the catheter hub when fitted into the catheter hub. and a support member having a fitting portion that communicates with the catheter hub and that supports the tube so that it is displaceable relative to the fitting portion, wherein when the fitting portion is fitted into the catheter hub, the tube is displaced relative to the fitting portion in a direction that connects the tube to the catheter hub, thereby entering an inserted state in which the tube is inserted into the catheter body, and in the inserted state, the inlet is located at the same position as the tip opening of the catheter body, at a position more distal than the tip opening, or at a position inside the tip portion, and the outlet is located more proximal than the inlet.

[0007] This shape-retaining device can prevent the tube from blocking the tip of the catheter when suction is performed with the suction tool, making it easy to determine whether the tip of the catheter has been inserted into a blood vessel by suctioning blood with the suction tool.

[0008] (2) In the shape-retaining device described in (1) above, the outlet may be formed in the side wall of the tube and may be arranged in the support member or the catheter hub in the inserted state.

[0009] In this way, the blood flowing through the lumen of the tube and the blood flowing between the tube and the catheter main body can be merged.

[0010] (3) In the shape-retaining device according to (1) or (2) above, an operating part for pushing the tube may be provided at the base end of the tube.

[0011] This makes it easier to displace the tube relative to the fitting portion in the direction in which it communicates with the catheter hub.

[0012] (4) In a shape-retaining device described in any one of (1) to (3) above, the support member may be provided with a tube movement regulating section that regulates the movement of the tube, and the tube may be in the inserted state when the movement of the tube is regulated by the tube movement regulating section.

[0013] In this way, the tube can be set in an appropriate position regardless of the operator's skill in operating the tube.

[0014] (5) A shape-retaining device according to any one of (1) to (4) above, wherein the support member has a connecting adapter in which a through hole is formed, the connecting adapter has the fitting portion on one end side of the through hole, the connecting adapter has a connection portion for connecting a suction instrument on the other end side of the through hole, and the connecting adapter has a tube introduction portion for introducing the tube toward the through hole between the one end and the other end of the through hole.

[0015] In this way, the tube can be inserted into the catheter body using an existing catheter member and suction device.

[0016] (6) In the shape-retaining device described in (5) above, an operating unit for pushing the tube is provided at the base end of the tube, and a cover that can be compressed in the direction of pushing the operating unit is connected to the operating unit and the tube introduction unit, and the cover may cover a portion of the tube located between the operating unit and the tube introduction unit.

[0017] This arrangement prevents the tube from being exposed to the outside, making it hygienic.

[0018] (7) In the shape-retaining device described in (6) above, a fixing portion for fixing the operating portion is formed in the tube introduction portion, and when the operating portion is fixed to the fixing portion, the tube may be in the inserted state.

[0019] In this way, it is possible to prevent deviation of the relative position between the catheter body and the tube inserted into the catheter body.

[0020] (8) A shape-retaining device according to any one of (1) to (4) above, wherein the support member has a syringe barrel having the fitting portion formed at the tip thereof and a plunger that can move within the syringe barrel, and the tube may pass through the plunger.

[0021] In this way, the tube can be inserted into the catheter body without the connection adapter, which reduces the number of parts and allows for miniaturization.

[0022] (9) In the shape-retaining device described in (8) above, the support member may include a gasket that seals between the plunger and the syringe barrel, and a sealing member that seals between the plunger and the tube.

[0023] This makes it possible to prevent blood drawn into the syringe barrel from leaking out of the syringe barrel.

[0024] (10) In the shape-retaining device according to (9) above, the gasket and the sealing member may be integrally formed.

[0025] In this way, the number of parts can be reduced.

[0026] (11) A shape-retaining device according to any one of (8) to (10) above, wherein the syringe barrel is provided with a plunger movement regulating section that regulates movement of the plunger in a direction toward the base end of the syringe barrel, and when the plunger movement regulating section regulates movement of the plunger in a direction toward the base end of the syringe barrel, the inlet may be located at the same position as the tip opening, at a position closer to the tip opening or at an internal position of the tip, and the outlet may be located in the syringe barrel.

[0027] In this way, the tube can be set in an appropriate position regardless of the operator's skill in operating the tube.

[0028] According to this aspect of the present invention, the tube can prevent the tip of the catheter from being blocked when the suction device is used for suctioning blood, making it easy to determine whether the tip of the catheter has been inserted into a blood vessel by using the suction device to suction blood.

[0029] Fig. 1 is a diagram showing a shape-retaining device and a catheter member according to a first embodiment. Fig. 2 is a perspective view showing a base end portion of a tube. Fig. 3 is a diagram showing a state in which a catheter member and a suction instrument are connected by a connection adapter. Fig. 4 is a diagram showing a state in which a tube introduced from a connection adapter is inserted into a catheter member. Fig. 5 is a diagram showing a case in which blood is aspirated from the state shown in Fig. 4. Fig. 6 is a diagram showing a shape-retaining device and a catheter member according to a second embodiment. Fig. 7 is a diagram showing a state in which a catheter member and a suction instrument are connected. Fig. 8 is a diagram showing a state in which a tube is inserted into a catheter member. Fig. 9 is a diagram showing a case in which blood is aspirated from the state shown in Fig. 8.

[0030] First Embodiment As shown in FIG. 1, a shape-retaining device 10 according to a first embodiment is connected to a catheter member 12 when in use.

[0031] The catheter member 12 includes a catheter body 14 and a catheter hub 16 connected to the proximal end of the catheter body 14. The catheter body 14 is formed in a tubular shape with a lumen 18 therein. The catheter body 14 is flexible. The distal end of the catheter body 14 has an outer peripheral surface that is a distal end outer surface 20 that tapers toward the distal end. The distal end of the catheter body 14 has a distal end opening 22 that opens toward the distal end. The distal end opening 22 is located radially inward of the distal end outer surface 20 and communicates with the lumen 18. The distal end of the catheter body 14 having the distal end opening 22 gradually becomes thinner in the radial direction toward the distal end.

[0032] The catheter hub 16 is formed in a cylindrical shape with a hub lumen 24. The catheter hub 16 has a proximal end opening 26 that opens in the proximal direction. The hub lumen 24 of the catheter hub 16 communicates with the lumen 18 of the catheter body 14 via the proximal end opening 23 of the catheter body 14.

[0033] The catheter member 12 is used for suction with a suction device 28. The suction device 28 is, for example, but not limited to, a syringe. When the suction device 28 is a syringe, the suction device 28 has a syringe barrel 30, a plunger 32, and a gasket 34.

[0034] The syringe barrel 30 has a barrel body 30A and a nozzle 30B protruding from the barrel body 30A. The outer diameter of the nozzle 30B of the syringe barrel 30 is smaller than the outer diameter of the barrel body 30A. A passage 30C is formed in the nozzle 30B of the syringe barrel 30, which communicates with the interior of the barrel body 30A. The plunger 32 is provided so as to be movable inside the barrel body 30A. A gasket 34 seals the gap between the syringe barrel 30 and the plunger 32. The gasket 34 is fixed to the tip of the plunger 32.

[0035] The shape-retaining device 10 is a device that prevents clogging of the distal end of the catheter main body 14. The shape-retaining device 10 includes a tube 40 and a support member 50.

[0036] The tube 40 is a member inserted into the lumen 18 of the catheter body 14. The tube 40 is harder than at least the distal end of the catheter body 14. The tube 40 has an inlet 42 formed therein, through which blood flows in. The inlet 42 is located at the distal end E1 of the tube 40. The tube 40 has an outlet 44 formed therein, through which blood flows out. The outlet 44 is formed in the side wall of the tube 40. The tube 40 has a lumen 46 formed therein. The lumen 46 of the tube 40 communicates with the inlet 42 and the outlet 44. Note that the lumen 46 of the tube 40 is formed from the distal end E1 to the proximal end E2 of the tube 40, but is not limited thereto. The lumen 46 of the tube 40 may be formed from the distal end E1 to the outlet 44 of the tube 40, but may not necessarily be formed from the outlet 44 to the proximal end E2.

[0037] As shown in FIG. 2 , an operating unit 48 for pushing the tube 40 is provided at the base end E2 of the tube 40. The operating unit 48 is formed, for example, in a plate shape. The operating unit 48 has a pressure-receiving surface 48F that receives the operation of pushing the tube 40. The pressure-receiving surface 48F is located on the side of the operating unit 48 opposite the base end E2 of the tube 40. The operating unit 48 may be provided with a gripping portion 48A. The gripping portion 48A is formed, for example, in a rod shape extending from the pressure-receiving surface 48F in a direction opposite to the direction in which the tube 40 is pushed. The operating unit 48 may be provided with a pair of protrusions 48B to restrict movement of the tube 40. The pair of protrusions 48B protrude from the operating unit 48 in, for example, a direction intersecting the direction in which the tube 40 is pushed.

[0038] As shown in FIG. 1 , the support member 50 has a connection adapter 52. The connection adapter 52 is an adapter capable of connecting the catheter hub 16 and the suction instrument 28. The connection adapter 52 is formed in a tubular shape. A through hole 54 is formed in the connection adapter 52. The through hole 54 extends in the direction along which the connection adapter 52 extends. The connection adapter 52 is provided with a fitting portion 56, a connection portion 58, and a tube introduction portion 60.

[0039] The fitting portion 56 is a portion formed to be able to fit into the catheter hub 16. The fitting portion 56 is provided in a portion of the connection adapter 52 located on one end side of the through hole 54. The fitting portion 56 is formed to be able to be inserted into the base-end opening 26 of the catheter hub 16. When the fitting portion 56 is inserted into the base-end opening 26 of the catheter hub 16, it fits liquid-tight with the inner circumferential surface of the catheter hub 16. In this case, the hub lumen 24 of the catheter hub 16 and the through hole 54 of the connection adapter 52 communicate with each other. In addition, the gap between the catheter hub 16 and the fitting portion 56 is sealed liquid-tight.

[0040] The connection part 58 is a portion formed so that the suction tool 28 can be connected. The connection part 58 is provided in a portion of the connection adapter 52 that is located on the other end side of the through-hole 54. When the suction tool 28 is a syringe, the connection part 58 is connected to the nozzle 30B of the syringe barrel 30. When the suction tool 28 is connected to the connection part 58, suction by the suction tool 28 can be performed from the catheter body 14 via the through-hole 54.

[0041] The tube introduction section 60 is a section formed so that the tube 40 can be introduced toward the through-hole 54. The tube introduction section 60 is provided in a portion of the connection adapter 52 that is located between one end and the other end of the through-hole 54. The tube introduction section 60 has an introduction pipe 62, a support base 64, and a tube movement restriction section 66.

[0042] One end of the introduction pipe 62 is connected to the outer peripheral surface of the connection adapter 52. The other end of the introduction pipe 62 is connected to the support base 64. A tube insertion hole 64H is formed in the support base 64. The tube insertion hole 64H communicates with the through-hole 54 through the inside of the introduction pipe 62. The tube 40 is inserted through the inside of the introduction pipe 62 and the tube insertion hole 64H. The base end E2 of the tube 40 is disposed outside. When the operation unit 48 provided at the base end E2 of the tube 40 is pressed, the tube 40 is introduced into the through-hole 54. A valve body 65 is provided in the tube insertion hole 64H to seal between the tube 40 and the support base 64. Note that the valve body 65 does not necessarily have to be provided.

[0043] The introduction pipe 62 extends in a direction inclined with respect to the extending direction of the through hole 54. The introduction pipe 62 is inclined so as to move away from the connection adapter 52 as it approaches the other end of the through hole 54. This makes it easier for the tip E1 of the tube 40 introduced into the through hole 54 to be displaced toward the fitting portion 56.

[0044] A cover 68 that is compressible in the direction of pushing the operating unit 48 is connected between the operating unit 48 provided at the proximal end E2 of the tube 40 and the support base 64. The cover 68 may be formed, for example, as a flexible tubular film using a material such as polyethylene or polypropylene. The cover 68 covers the portion of the tube 40 that is located between the operating unit 48 and the support base 64. Therefore, the tube 40 is not exposed to the outside, making it hygienic.

[0045] The tube movement restricting portion 66 is a portion that restricts the movement of the tube 40. The tube movement restricting portion 66 extends from the support base 64 toward the operation unit 48. The tube movement restricting portion 66 may be formed integrally with the support base 64. As shown in FIG. 2, the tube movement restricting portion 66 is formed, for example, in a tubular shape. The tube movement restricting portion 66 is formed with a fixing portion 70 that fixes the operation unit 48. For example, as shown in FIG. 2, if the operation unit 48 is provided with a pair of protrusions 48B, the fixing portion 70 is formed at the base end of the tube movement restricting portion 66 as a recess that fits with the pair of protrusions 48B.

[0046] Next, a description will be given of how to use the shape-retaining device 10. First, the user inserts a catheter assembly having a needle member (not shown) inserted into the catheter member 12 into a blood vessel BV of the living body, and then removes the needle member from inside the catheter member 12. As a result, the catheter member 12 is placed with the tip of the catheter main body 14 disposed in the blood vessel BV of the living body, as shown in Figure 3.

[0047] Next, the user connects the catheter member 12 and the suction device 28 via the connecting adapter 52. In this case, the fitting portion 56 of the connecting adapter 52 is inserted into the catheter hub 16. The suction device 28 is connected to the connecting portion 58 of the connecting adapter 52. At this stage, the tube 40 is in its initial state. In the initial state, the inlet 42 of the tube 40 is located in the through-hole 54 of the connecting adapter 52, and the outlet 44 of the tube 40 is located inside the cover 68. Note that the position of the inlet 42 of the tube 40 in the initial state may be the tube introduction portion 60, such as the introduction tube 62.

[0048] Next, the user presses the operating unit 48 to begin inserting the tube 40 into the catheter main body 14. As the user begins to press the operating unit 48, the distance of the operating unit 48 from the tube movement restricting portion 66 of the tube introducer 60 gradually decreases. In response to this decrease, the cover 68 disposed between the operating unit 48 and the tube movement restricting portion 66 gradually compresses. Furthermore, the tube 40 moves in response to the decrease in the distance of the operating unit 48 from the tube movement restricting portion 66. In this case, the tube 40 is guided by the inner circumferential surface of the connection adapter 52 surrounding the through hole 54 and advances through the through hole 54 toward the proximal end opening 26 of the catheter hub 16. In other words, the tube 40 is displaced relative to the fitting portion 56 of the connection adapter 52 in a direction communicating with the catheter hub 16 (toward the distal end).

[0049] 4, when the operating unit 48 comes into contact with the tube movement restricting portion 66 of the tube introduction portion 60, the movement of the tube 40 is restricted, and the insertion of the tube 40 into the catheter main body 14 is completed. In this case, the tube 40 is in an inserted state inserted into the catheter main body 14. In other words, when the movement of the tube 40 is restricted by the tube movement restricting portion 66, the tube 40 is in an inserted state. Therefore, regardless of the skill in operating the operating unit 48, the tube 40 can be set in an appropriate position.

[0050] When the tube 40 is inserted, the inlet 42 of the tube 40 is located distal to the distal opening 22 of the catheter main body 14. The outlet 44 of the tube 40 is located in a through-hole 54 of the connection adapter 52, which is proximal to the proximal opening 23 of the catheter main body 14. The position of the inlet 42 of the tube 40 when the tube 40 is inserted may be the same as the distal opening 22 of the catheter main body 14. The position of the outlet 44 of the tube 40 when the tube 40 is inserted may also be in the hub lumen 24 of the catheter hub 16.

[0051] The operation unit 48, which contacts the tube movement restricting portion 66, is fixed to a fixing portion 70 formed on the tube movement restricting portion 66. As shown in Fig. 2, in this embodiment, the operation unit 48 is fixed by fitting a pair of protrusions 48B provided on the operation unit 48 into recesses (fixing portion 70) formed at the base end of the tube movement restricting portion 66. Therefore, deviation in the relative position between the catheter main body 14 and the tube 40 inserted into the catheter main body 14 is suppressed.

[0052] Once the tube 40 is in the inserted state, the user begins suction with the suction instrument 28. In this embodiment, the tube 40, which is harder than the catheter body 14, is inserted into the catheter body 14. This prevents the tip of the catheter body 14 from being blocked by negative pressure generated in response to suction by the suction instrument 28. As a result, it is possible to determine whether the tip of the catheter body 14 is inserted into a blood vessel based on whether blood is flowing into the lumen 46 of the tube 40 or the amount of blood flowing in.

[0053] As shown in FIG. 5 , when blood flows into the lumen 46 of the tube 40, the blood flows out from the outlet 44 into the through-hole 54 of the connection adapter 52. Furthermore, when blood flows between the tube 40 and the catheter main body 14, the blood flows out of the through-hole 54 via the hub lumen 24. That is, the blood flowing through the lumen 46 of the tube 40 and the blood flowing between the tube 40 and the catheter main body 14 merge at the through-hole 54 of the connection adapter 52. The blood flowing into the through-hole 54 is sucked into the suction device 28. When the suction device 28 is a syringe, the blood flowing into the through-hole 54 passes through the nozzle 30B of the syringe barrel 30 and accumulates inside the syringe barrel 30. When the tube 40 is inserted, it is desirable that the outlet 44 be close to the tip of the suction device 28. When the outlet 44 is close to the tip of the suction device 28, blood can be efficiently sucked.

[0054] Second Embodiment Next, a shape-retaining device 10 according to a second embodiment will be described. In this embodiment, components equivalent to those in the first embodiment are denoted by the same reference numerals as those used in the first embodiment. Furthermore, in this embodiment, descriptions that overlap with those in the first embodiment will be omitted.

[0055] 6, in this embodiment, the support member 50 does not include the connection adapter 52 of the first embodiment. The tube 40 is supported by the suction device 28. That is, in this embodiment, the support member 50 is the suction device 28.

[0056] The suction instrument 28 of this embodiment is a syringe, and similar to the first embodiment, includes a syringe barrel 30, a plunger 32, and a gasket 34. A tube insertion hole 32H is formed in the plunger 32 and the gasket 34 along the axis AX of the syringe. A tube 40 is inserted through the tube insertion hole 32H and passes through the plunger 32 and the gasket 34. The tube 40 is disposed along the axis AX of the syringe and is movable relative to the plunger 32.

[0057] In the initial state of the tube 40, the inlet 42 and outlet 44 of the tube 40 are located inside the syringe barrel 30 and do not protrude to the outside of the syringe barrel 30. Therefore, the tip region of the tube 40 inserted into the catheter body 14 is not exposed to the outside, which is hygienic.

[0058] In the suction instrument 28 of this embodiment, the nozzle 30B of the syringe barrel 30 can be inserted into the proximal end opening 26 of the catheter hub 16. When the nozzle 30B of the syringe barrel 30 is inserted into the proximal end opening 26 of the catheter hub 16, it fits liquid-tightly with the inner circumferential surface of the catheter hub 16. In this case, the hub lumen 24 of the catheter hub 16 communicates with the interior of the syringe barrel 30. Furthermore, the gap between the catheter hub 16 and the nozzle 30B of the syringe barrel 30 is sealed liquid-tight. In other words, the nozzle 30B of the syringe barrel 30 corresponds to the fitting portion 56 of the first embodiment.

[0059] The suction instrument 28 of this embodiment additionally includes a plunger movement restricting portion 72 and a seal member 74 .

[0060] The plunger movement restricting portion 72 restricts movement of the plunger 32 in the direction toward the base end of the syringe barrel 30. The plunger movement restricting portion 72 is provided on the barrel body 30A. The plunger movement restricting portion 72 extends from the inner wall on the base end side of the barrel body 30A to the base end opening 30F of the syringe barrel 30. Therefore, the base end opening 30F of the syringe barrel 30 is smaller than when the plunger movement restricting portion 72 is not provided. The plunger movement restricting portion 72 may be formed integrally with the barrel body 30A or may be formed separately. The shape of the plunger movement restricting portion 72 may be annular or convex, and is not particularly limited.

[0061] The plunger 32 has different outer diameters at the distal end 32A and the proximal end 32B. The outer diameter of the distal end 32A of the plunger 32 is larger than the outer diameter of the proximal end 32B of the plunger 32. The proximal end 32B of the plunger 32 can be inserted through the proximal end opening 30F of the syringe barrel 30. On the other hand, the distal end 32A of the plunger 32 cannot be inserted through the proximal end opening 30F of the syringe barrel 30.

[0062] As the plunger 32 moves toward the base end of the syringe barrel 30, the surface 32F of the tip portion 32A of the plunger 32 facing the base end 32E abuts against the plunger movement restricting portion 72, and the movement of the plunger 32 is restricted.

[0063] The seal member 74 provides a liquid-tight seal between the plunger 32 and the tube 40. The gasket 34 and the seal member 74 may be formed integrally or separately. When the gasket 34 and the seal member 74 are formed integrally, the number of parts can be reduced.

[0064] Next, the use of the shape-retaining device 10 will be described. First, the user inserts a catheter assembly having a needle member (not shown) inserted into the catheter member 12 into a blood vessel BV of the living body, and then removes the needle member from inside the catheter member 12. As a result, the catheter member 12 is placed with the tip of the catheter main body 14 first disposed in the blood vessel BV of the living body, as shown in Figure 7.

[0065] Next, the user connects the suction device 28 to the catheter hub 16. In this case, the nozzle 30B of the syringe barrel 30 is inserted into the proximal end opening 26 of the catheter hub 16, and the nozzle 30B of the syringe barrel 30 is fitted to the catheter hub 16. At this stage, the tube 40 is in its initial state. In the initial state, the inlet 42 and outlet 44 of the tube 40 are located inside the syringe barrel 30.

[0066] Next, the user presses the control unit 48 to begin inserting the tube 40 into the catheter body 14. When the control unit 48 begins to be pressed toward the distal end, the tube 40 moves. In this case, the tube 40 advances along the axis AX of the syringe toward the proximal end opening 26 of the catheter hub 16. In other words, the tube 40 is displaced relative to the syringe barrel 30 in a direction that connects it to the catheter hub 16. Note that even when the control unit 48 is pressed, the plunger 32 abuts against the wall portion on the distal end side of the syringe barrel 30 and does not advance toward the proximal end opening 26 of the catheter hub 16.

[0067] As shown in Figure 8, when the operating unit 48 comes into contact with the base end 32E of the plunger 32, the movement of the tube 40 is restricted, and the insertion of the tube 40 into the catheter body 14 is completed. In this case, the tube 40 is in an inserted state inserted into the catheter body 14. In other words, when the movement of the tube 40 is restricted by the plunger 32, the tube 40 is in an inserted state. The plunger 32 corresponds to the tube movement restricting unit 66 of the first embodiment. Therefore, similar to the first embodiment, the tube 40 can be set in an appropriate position regardless of the skill level in operating the operating unit 48.

[0068] When the tube 40 is inserted, the inlet 42 of the tube 40 is located distal to the distal opening 22 of the catheter body 14. The outlet 44 of the tube 40 is located in the hub lumen 24 of the catheter hub 16, proximal to the proximal opening 23 of the catheter body 14.

[0069] Once the tube 40 is in the inserted state, the user pulls the plunger 32 in the direction toward the proximal end of the syringe barrel 30 to initiate suction with the suction instrument 28. In this embodiment, as in the first embodiment, the tube 40, which is harder than the catheter body 14, is inserted into the catheter body 14. This prevents the tip of the catheter body 14 from being blocked by negative pressure generated in response to suction by the suction instrument 28. As a result, it is possible to determine whether the tip of the catheter body 14 is inserted into a blood vessel based on whether blood is flowing into the lumen 46 of the tube 40 or the amount of blood flowing in.

[0070] As described above, in the inserted state of the tube 40, the operating portion 48 provided at the base end E2 of the tube 40 is in contact with the base end 32E of the plunger 32. Therefore, when the plunger 32 starts to move in a direction toward the base end of the syringe barrel 30, the tube 40 also moves in a direction toward the base end of the syringe barrel 30 in response to the movement of the plunger 32.

[0071] When suction by the suction device 28 is initiated and blood flows into the lumen 46 of the tube 40, the blood flows out from the outlet 44. The blood flowing out from the outlet 44 joins with blood flowing between the tube 40 and the catheter body 14 from the distal end opening 22 of the catheter body 14, and flows out into the hub lumen 24 of the catheter hub 16. The blood that has flowed into the hub lumen 24 of the catheter hub 16 passes through the passage 30C of the nozzle 30B of the syringe barrel 30 and accumulates inside the syringe barrel 30.

[0072] 9 , as the plunger 32 moves toward the base end of the syringe barrel 30, the surface 32F of the tip end 32A of the plunger 32 facing the base end 32E comes into contact with the plunger movement restricting portion 72, restricting the movement of the plunger 32. This terminates suction by the suction instrument 28. When the movement of the plunger 32 is restricted, the tube 40, which follows the movement of the plunger 32, also stops. Note that even if the movement of the plunger 32 is restricted, the tube 40 can still move in the direction of being removed from the plunger 32.

[0073] With the movement of the plunger 32 restricted, the tube 40 remains inserted into the catheter body 14. The inlet 42 of the tube 40 is located distal to the tip opening 22 of the catheter body 14. The outlet 44 of the tube 40 is located inside the barrel body 30A, which is proximal to the base end opening 23 of the catheter body 14. This makes it easy to accumulate blood inside the syringe barrel 30. Note that with the tube 40 inserted, the inlet 42 of the tube 40 may be located at the same position as the tip opening 22 of the catheter body 14.

[0074] In this manner, in this embodiment, the tube 40 is supported by the suction device 28 so as to be insertable into the catheter body 14. Therefore, the same effects as in the first embodiment can be obtained even without the connection adapter 52 of the first embodiment. As a result, this embodiment can reduce the number of parts compared to the first embodiment, and can achieve miniaturization.

[0075] [Modified Embodiment] The above embodiment may be modified as follows.

[0076] For example, only the distal end region of the tube 40 may be harder than the catheter body 14. In this case, the region of the tube 40 other than the distal end region may have the same hardness as the catheter body 14, or may be softer than the catheter body 14. The distal end region of the tube 40 is equal to or greater than the region from the distal end E1 of the tube 40 to a position separated by a distance equivalent to the length of the catheter body 14 in the extension direction.

[0077] Furthermore, the outer diameter of the tube 40 does not have to be the same from the distal end E1 of the tube 40 to the proximal end E2 of the tube 40. Similarly, the inner diameter of the tube 40 does not have to be the same from the distal end E1 of the tube 40 to the proximal end E2 of the tube 40.

[0078] Furthermore, in the inserted state where the tube 40 is inserted into the catheter body 14, the inlet 42 of the tube 40 may be located inside the tip of the catheter body 14. In this case, the inlet 42 is located within a range from the tip of the catheter body 14 to a position spaced a distance equivalent to half the inner diameter of the catheter body 14. The closer the position of the inlet 42 is to the tip opening 22 of the catheter body 14, the more preferable it is.

[0079] In the second embodiment, a fixing portion 70 may be provided at the base end 32E of the plunger 32. In this case, as in the first embodiment, it is possible to suppress deviation in the relative position between the catheter main body 14 and the tube 40 inserted into the catheter main body 14.

[0080] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention.

Claims

1. A shape-retaining device for preventing blockage of the tip of the catheter body, which is used by being connected to a catheter member having a catheter body to be placed in a blood vessel and a catheter hub fixed to the base end of the catheter body, comprising: a tube having an inlet for introducing blood, an outlet for introducing blood, and an inner cavity communicating between the inlet and the outlet, the tip region including at least the inlet being harder than the tip of the catheter body; and a support member which is capable of fitting into the catheter hub, has a fitting portion which communicates with the catheter hub when fitted into the catheter hub, and supports the tube in a displaceable manner relative to the fitting portion; and when the fitting portion is fitted into the catheter hub, the tube is displaced relative to the fitting portion in the direction communicating with the catheter hub, thereby entering an inserted state in which it is inserted into the catheter body, A shape retention device in which, in the inserted state, the inlet is located at the same position as the tip opening of the catheter body, at a position distal to the tip opening, or at an internal position of the tip portion, and the outlet is located proximal to the inlet.

2. A shape-retaining device according to claim 1, wherein the outlet is formed in a side wall of the tube and is disposed in the support member or the catheter hub in the inserted state.

3. A shape-retaining device according to claim 1, wherein an operating part for pushing the tube is provided at the base end of the tube.

4. A shape retention device as described in claim 1, wherein the support member is provided with a tube movement regulating section that regulates the movement of the tube, and when the movement of the tube is regulated by the tube movement regulating section, the tube is in the inserted state.

5. A shape retention device as described in claim 2, wherein the support member has a connecting adapter in which a through hole is formed, the connecting adapter has the fitting portion provided on one end side of the through hole, the connecting adapter has a connection portion for connecting a suction instrument provided on the other end side of the through hole, and the connecting adapter has a tube introduction portion for introducing the tube toward the through hole provided between the one end and the other end of the through hole.

6. A shape retention device as described in claim 5, wherein an operating section for pushing the tube is provided at the base end of the tube, and a cover that is compressible in the direction of pushing the operating section is connected to the operating section and the tube introduction section, and the cover covers a portion of the tube located between the operating section and the tube introduction section.

7. A shape retention device as claimed in claim 6, wherein a fixing part for fixing the operating part is formed in the tube introduction part, and when the operating part is fixed to the fixing part, the tube is in the inserted state.

8. A shape-retaining device according to claim 2, wherein the support member has a syringe barrel having the fitting portion formed at its tip and a plunger movable within the syringe barrel, and the tube passes through the plunger.

9. A shape-retaining device according to claim 8, wherein the support member comprises a gasket for sealing between the plunger and the syringe barrel, and a sealing member for sealing between the plunger and the tube.

10. A shape-retaining device according to claim 9, wherein said gasket and said sealing member are integrally formed.

11. A shape retention device as described in claim 8, wherein the syringe barrel is provided with a plunger movement regulating section which regulates movement of the plunger in a direction toward the base end of the syringe barrel, and when the movement of the plunger is regulated in the direction toward the base end of the syringe barrel by the plunger movement regulating section, the inlet is located at the same position as the tip opening, at a position closer to the tip than the tip opening or at a position inside the tip, and the outlet is located in the syringe barrel.

Images