Catheter Assembly

Abstract

To provide a catheter assembly used in infusion, blood transfusion, or the like.SOLUTION: A catheter assembly 10 includes an inner needle 12, a catheter 30 having a lumen where the inner needle is detachably inserted, and a warp suppressing mechanism 90 for suppressing warp of the inner needle by supporting the inner needle through the catheter. In the catheter, one or more catheter side part openings are formed. The warp suppressing mechanism has a contact support part brought into contact with the catheter when the catheter advances relative to the inner needle. The contact support part can support a proximal end side rather than a distal end part of the catheter side part opening located closest to a distal end side out of one or more catheter side part openings or a proximal end side rather than a distal end part of a step part provided on the catheter.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a catheter assembly used, for example, when performing fluid infusion, blood transfusion, or the like. [Background technology]

[0002] When constructing an introduction portion for infusion or blood transfusion in a patient, a catheter assembly having a multi-structure needle with an inner needle inserted into a catheter (outer needle) is used, as disclosed in Patent Document 1, for example. When using this catheter assembly, a user inserts the multi-structure needle into a patient, advances the catheter relative to the inner needle to insert it into a blood vessel, and then detaches the inner needle from the catheter to place the catheter in place. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-43445 A Summary of the Invention

[0004] One aspect of the present invention is a catheter assembly including an inner needle, a catheter having a lumen through which the inner needle is removably inserted, and a deflection suppression mechanism that suppresses deflection of the inner needle by supporting the inner needle via the catheter, wherein the catheter has one or more catheter side openings. a step portion provided so as to increase the outer diameter of the catheter, the step portion being located on the proximal side of the catheter side opening that is located on the most distal side of the one or more catheter side openings; the deflection suppression mechanism has a contact support portion that can come into contact with the catheter when the catheter advances relative to the inner needle, and the contact support portion is located on the proximal side of the distal end portion of the catheter side opening that is located on the most distal side of the one or more catheter side openings, or The above Step Club The catheter assembly is capable of supporting the proximal end side more easily than the catheter assembly. [Brief description of the drawings]

[0005] [Figure 1]1 is a perspective view showing an overall configuration of a catheter assembly according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a side cross-sectional view showing the catheter, catheter hub, and inner needle of FIG. 1. [Diagram 3] FIG. 11 is a side cross-sectional view showing a catheter, a catheter hub, and an inner needle of a catheter assembly according to a second embodiment. [Figure 4] FIG. 11 is a side cross-sectional view showing a catheter, a catheter hub, and an inner needle of a catheter assembly according to a third embodiment. [Diagram 5] FIG. 11 is a plan cross-sectional view showing a catheter, a catheter hub, and an inner needle of a catheter assembly according to a fourth embodiment. [Figure 6] 6A to 6F are cross-sectional views of catheters and inner needles according to first to sixth configuration examples. [Figure 7] FIG. 7A is a cross-sectional view of a catheter and an inner needle according to a seventh configuration example, and FIG. 7B is a cross-sectional view of a catheter and an inner needle according to an eighth configuration example. [Figure 8] FIG. 13 is a perspective view showing the overall configuration of a catheter assembly according to a fifth embodiment. [Figure 9] 9 is a side cross-sectional view showing the catheter, the inner needle, and the bending suppression mechanism of FIG. 8. [Figure 10] FIG. 9 is a perspective view showing the operation of the catheter assembly of FIG. 8. [Figure 11] FIG. 13 is a perspective view showing the overall configuration of a catheter assembly according to a sixth embodiment. [Figure 12] Fig. 12A is a cross-sectional view of the multi-tube structure of Fig. 11. Fig. 12B is a cross-sectional view showing the operation when a liquid flows through the catheter. [Figure 13] FIG. 13 is a perspective view showing the overall configuration of a catheter assembly according to a seventh embodiment. [Figure 14] FIG. 13 is a perspective view showing the overall configuration of a catheter assembly according to an eighth embodiment. [Figure 15] 15 is a partial cross-sectional view showing the deflection suppression mechanism of FIG. 14. [Figure 16] FIG. 13 is a schematic side view showing the overall configuration of a catheter assembly according to a ninth embodiment. [Figure 17] FIG. 13 is a perspective view showing the overall configuration of a catheter assembly according to a tenth embodiment. [Figure 18] 18 is an enlarged perspective view of the deflection suppression mechanism of FIG. 17. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0006] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A catheter assembly according to a preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0007] [First embodiment] The catheter assembly 10 according to the first embodiment is a medical device used when performing infusion or blood transfusion on a patient (living body), and a catheter 30 is punctured, inserted, and left in the patient's body to form an inlet and outlet for liquid (medicinal liquid or blood). This catheter assembly 10 is configured to insert a catheter (e.g., a central venous catheter, PICC, midline catheter, etc.) that is longer than a peripheral venous catheter. The catheter assembly 10 may also be used to insert a peripheral venous catheter that is shorter than a central venous catheter. Furthermore, the catheter assembly 10 is not limited to a venous catheter, and may also be used to insert an arterial catheter such as a peripheral arterial catheter.

[0008] 1, the catheter assembly 10 includes an inner needle 12, a housing 20 (inner needle hub) that fixes and holds the inner needle 12, a catheter 30 that is disposed on the outside of the inner needle 12, and a catheter hub 50 that fixes and holds the catheter 30. Furthermore, the catheter assembly 10 includes a catheter operating member 60 that operates the advancement and retreat of the catheter 30 and the catheter hub 50, and a guidewire 70 and a guidewire operating member 80 that guide the advancement of the catheter 30.

[0009] The catheter 30 according to this embodiment is configured as a multi-lumen type having multiple (two in this embodiment) lumens 31 therein (see also FIG. 2). In the catheter assembly 10, in an assembled state before use (pre-puncture state), the inner needle 12 is inserted and positioned in one main lumen 34 of the multiple lumens 31, and a guidewire 70 is housed inside the inner needle 12 to form a multi-structure needle 11.

[0010] In the pre-puncture state, the needle tip 13 of the inner needle 12 protrudes beyond the tip of the catheter 30, while the guide wire 70 is disposed within the inner needle 12. The housing 20 accommodates the base end side of the multi-structure needle 11 therein, and also accommodates the catheter hub 50, the catheter operating member 60, and the guide wire operating member 80.

[0011] When using this catheter assembly 10, a user such as a doctor or a nurse grasps the housing 20 and inserts the multi-structure needle 11 into the patient's body. Furthermore, while maintaining the punctured state, the guide wire 70 is sent from the inner needle 12 into the blood vessel, and the catheter 30 is inserted into the blood vessel along the guide wire 70. Then, the inner needle 12 is retracted and removed from the catheter 30, so that the catheter 30 is placed in the blood vessel. In the placed state, the catheter 30 has two lumens 31 communicating with the blood vessel, so that treatments such as administering multiple types of medicines separately or taking blood while administering medicines can be performed. Each component of this catheter assembly 10 will be described in detail below.

[0012] 1 and 2, the inner needle 12 is configured as a hollow tube having sufficient rigidity to puncture the skin of a living body, and is provided at its tip with a sharp needle tip 13. A hollow portion 12a is provided inside the inner needle 12 along the axial direction. The inner needle 12 may have a solid structure without the hollow portion 12a.

[0013] The needle tip 13 has a blade surface 15 that is inclined at a predetermined angle with respect to the axis of the inner needle 12, formed by cutting a cylindrical tube obliquely. The blade surface 15 has an elliptical shape that surrounds a tip opening 15a that communicates with the hollow portion 12a. When the catheter assembly 10 is in use, the blade surface 15 faces the user (upward when the patient's body surface is considered to be downward). As a result, when puncturing, the edge of the blade surface 15 cuts the skin and is inserted into the body.

[0014] In the following, unless otherwise specified, the direction and position of each component of the catheter assembly 10 will be described based on the orientation of the blade surface 15 (see also the arrow directions in FIG. 1). In particular, the arrangement of the multiple lumens 31 of the catheter 30 will be described in relation to the blade surface 15.

[0015] 1 and 2 show an example of the blade surface 15 simply cut at an angle to the axis of the inner needle 12, but the shape of the blade surface 15 is not particularly limited. For example, the needle tip 13 may be configured as a lancet type in which two inclined blade surfaces 15 on the left and right form a cutting tip (ridge) in the center in the width direction, or may be configured as a back cut type in which the opposite side of the blade surfaces 15 is cut.

[0016] The inner needle 12 is provided with a hollow portion 12a and a hole portion 14 penetrating the outer surface. In other words, the inner needle 12, by means of the tip opening 15a, the hollow portion 12a, and the hole portion 14, constitutes an introduction path for checking blood flashback when the multi-structure needle 11 is punctured.

[0017] Examples of materials constituting the inner needle 12 include metal materials such as stainless steel, aluminum or an aluminum alloy, titanium or a titanium alloy, or hard resins, ceramics, etc. The inner needle 12 is firmly fixed to the housing 20 by an appropriate fixing means such as fusion, adhesion, or insert molding.

[0018] The housing 20 of the catheter assembly 10 is an inner needle hub 19 that fixedly holds the inner needle 12 and moves integrally with the inner needle 12, and constitutes a grip portion that is held by the user. The housing 20 has an overall elongated bowl shape, and is designed to be of an appropriate size (thickness and length) so that it is easy for the user to grip.

[0019] The housing 20 is provided with an accommodation space 20a for accommodating the catheter hub 50, the catheter manipulation member 60, and the guidewire manipulation member 80. A pair of side walls 21 sandwiching the accommodation space 20a extend parallel to the longitudinal direction, and have groove-shaped rail portions 21a on the inner surface of the distal end side formed higher than the proximal end side. The pair of rail portions 21a slidably accommodate the side edge 61a of the catheter manipulation member 60. The distal end side of one of the pair of side walls 21 (the left side wall 21 in FIG. 1) has a bulging portion 22 that bulges outward in the width direction. A support member 91, which is a deflection suppression mechanism 90, is attached to the arrangement recess 22a of the bulging portion 22.

[0020] The support member 91 is rotatably supported by the side wall 21 and has a sliding support portion 92 that protrudes rightward into the accommodation space 20a of the housing 20. This sliding support portion 92 rubs against the catheter 30 when the catheter 30 (multiple-structure needle 11) held by the catheter manipulation member 60 advances. This sliding support portion 92 does not need to be in contact with the catheter 30 before the catheter 30 is used or when the catheter 30 moves relative to the housing 20. In addition, the support member 91 has a groove portion (not shown) at the upper end portion that accommodates the side edge 61a of the catheter manipulation member 60 when the catheter manipulation member 60 is accommodated in the housing 20. The presence of the side edge 61a in this groove restricts rotation and allows the support member 91 to stand by while supporting the catheter 30. On the other hand, when the catheter manipulation member 60 advances, the side edge 61a of the support member 91 comes out of the groove portion, making it rotatable, and the catheter manipulation member 60 comes into contact with the support member 91, causing it to rotate toward the outside of the side wall 21. As a result, the catheter hub 50 and the catheter operating member 60 are smoothly advanced out of the housing 20 while the support member 91 (sliding support portion 92) remains in the housing 20.

[0021] The housing 20 also has a block-shaped needle holding portion 24 that holds the inner needle 12 at the axially intermediate position of the accommodating space 20a. A guide mechanism (not shown) that guides the sliding of the guidewire operating member 80 and restricts removal of the guidewire operating member 80 is provided on the proximal side of the housing 20 from the needle holding portion 24. Furthermore, a rear wall 25 that closes the accommodating space 20a is provided on the most proximal side of the housing 20.

[0022] The material of the housing 20 is not particularly limited, but may be, for example, a thermoplastic resin such as polypropylene, polycarbonate, polyamide, polysulfone, polyarylate, methacrylate-butylene-styrene copolymer, etc. In the illustrated example, the housing 20 is configured so that the upper surface of the storage space 20a is exposed, but the housing 20 may be formed in a rectangular tube shape with the storage space 20a covered by an upper wall.

[0023] On the other hand, the catheter 30 of the catheter assembly 10 is formed in a perfect circular shape in a cross section perpendicular to the axial direction, and extends an appropriate length along the axial direction. The length of the catheter 30 is not particularly limited and can be designed appropriately depending on the application, various conditions, etc., and is set to, for example, about 14 to 500 mm.

[0024] 2, the catheter 30 is composed of a main body 32 which constitutes most of the axial direction, and a soft tip 33 (flexible portion) which is provided at the tip of the main body 32 and is softer than the main body 32. The main body 32 and the soft tip 33 are firmly fixed to each other by an appropriate fixing method such as heat fusion or adhesion, and their outer circumferential surfaces are formed continuously. In addition, the connecting boundary between the main body 32 and the soft tip 33 overlap each other in a tapered manner, gradually changing the physical properties of the catheter 30.

[0025] The multiple lumens 31 in the catheter 30 include a main lumen 34 (first lumen) through which the inner needle 12 is inserted in the pre-puncture state, and a sub-lumen 41 (second lumen) extending parallel to the main lumen 34. The main lumen 34 and the sub-lumen 41 are each formed in a perfect circle shape in a cross-sectional view perpendicular to the axis of the catheter 30.

[0026] The main lumen 34 is provided over the entire axial length of the catheter 30, and communicates with a first distal end opening 34a (main opening) formed at the distal end of the catheter 30 and a first proximal end opening 34b formed at the proximal end of the catheter 30. The needle tip 13 of the inner needle 12 is exposed from the first distal end opening 34a.

[0027] The inner circumferential surface of the catheter 30 that constitutes the main lumen 34 is divided, with respect to a predetermined axial position P as the base point, into a tip inner circumferential surface 36 that has zero (narrow) clearance from the outer circumferential surface 16 of the inner needle 12, and a basic inner circumferential surface 38 that forms a gap 39 with the outer circumferential surface 16 of the inner needle 12. In addition, a tapered inner circumferential surface 37 that connects the tip inner circumferential surface 36 and the basic inner circumferential surface 38 is formed at the tip of the basic inner circumferential surface 38.

[0028] The diameter of the tip inner circumferential surface 36 is the same as or slightly smaller than the outer diameter of the outer circumferential surface 16 of the inner needle 12, thereby forming an intimate contact portion 35 that comes into intimate contact with the outer circumferential surface 16 of the inner needle 12 and closing a gap 39 in the basic inner circumferential surface 38. Therefore, the diameter of the tip inner circumferential surface 36 may be designed in accordance with the outer diameter of the inner needle 12, and may be in the range of 0.3 mm to 1.8 mm, for example. Furthermore, the length of the tip inner circumferential surface 36 in the longitudinal direction (axial direction) may be in the range of 0.1 mm to 4.0 mm, for example, in order to allow the tip of the catheter 30 to be inserted smoothly.

[0029] The soft tip 33 described above constitutes the tip of the catheter 30 together with the main body 32, and its inside forms a tip inner circumferential surface 36 (adhering portion 35). The tip of the tip inner circumferential surface 36 of the soft tip 33 forms a first tip opening 34a. The tip of the outer circumferential surface of the soft tip 33 is formed into a tapered tip portion 40 with an inclination that matches the inclination of the blade surface 15 of the needle tip 13 (or a gentler inclination than the blade surface 15), for example.

[0030] The tapered inner circumferential surface 37 of the main lumen 34 has a diameter that gradually decreases over a short axial range toward the distal end (distal inner circumferential surface 36). On the other hand, the basic outer circumferential surface 44 constitutes most of the inner circumferential surface of the main lumen 34 in the axial direction.

[0031] The diameter of the basic inner circumferential surface 38 is larger than the outer diameter of the outer circumferential surface 16 of the inner needle 12, that is, larger than the gap of the tip inner circumferential surface 36. This allows the inner needle 12 and the catheter 30 to slide smoothly. Furthermore, the hole 14 of the inner needle 12 faces the basic inner circumferential surface 38 and communicates with the gap 39 of the basic inner circumferential surface 38 before puncture. Therefore, it is possible to allow blood to flash back smoothly into the gap between the inner needle 12 and the catheter 30. The diameter of the basic inner circumferential surface 38 may be designed to be, for example, about 1.02 to 1.33 times the diameter of the tip inner circumferential surface 36.

[0032] The sub-lumen 41 is provided separated from the main lumen 34 along the axial direction of the catheter 30. In other words, the main lumen 34 and the sub-lumen 41 extend along axes parallel to each other inside the catheter 30. The sub-lumen 41 is bent radially outward at a midpoint on the tip side of the catheter 30 and communicates with a second lateral opening 41a (sub-opening) formed on the outer circumferential surface (side) of the catheter 30.

[0033] The second side opening 41a is provided at a position closer to the base end than the first tip opening 34a. The distance between the first tip opening 34a and the second side opening 41a is preferably 17 mm or more.

[0034] In the catheter assembly 10, the first tip opening 34a and the second side opening 41a are spaced apart by 17 mm or more, so that the drug flowing out of one of the first tip opening 34a and the second side opening 41a is mixed with blood in the blood vessel and then mixed with the drug flowing out of the other opening. In other words, incompatible drugs can be administered well using one catheter 30. The base end side of the sublumen 41 communicates with the second base end opening 41b, and this second base end opening 41b is adjacent to the first base end opening 34b.

[0035] In addition, the diameter of the inner peripheral surface of the sub-lumen 41 is set to a dimension smaller than the diameter of the inner peripheral surface (tip inner peripheral surface 36) of the main lumen 34 in this embodiment. That is, the multiple lumens 31 are composed of a large-diameter main lumen 34 in which the inner needle 12 is disposed, and a small-diameter sub-lumen 41 in which nothing is disposed. Furthermore, while the diameter of the main lumen 34 changes along the axial direction, the inscribed circle diameter of the sub-lumen 41 is constant along the axial direction of the catheter 30. The diameter of the sub-lumen 41 is not particularly limited as long as it is possible to introduce a drug from the second base end opening 41b and guide the drug to the second side opening 41a, and may be, for example, in the range of 0.3 to 1.2 mm.

[0036] On the other hand, the outer peripheral surface of the catheter 30 is formed into a tip outer peripheral surface 42 with a small outer diameter in the range from the tip to a predetermined position P. For example, the tip outer peripheral surface 42 has an outer diameter that is approximately one size larger than the inner needle 12. In addition, the outer peripheral surface of the catheter 30 has a tapered outer peripheral surface 43 that becomes thicker from the predetermined position P toward the base end, and a basic outer peripheral surface 44 that is connected to the base end of the tapered outer peripheral surface 43 and is thicker than the tip outer peripheral surface 42. The basic outer peripheral surface 44 is provided at the position where the sub-lumen 41 is formed.

[0037] In the above catheter 30, in the axial direction, the tip inner circumferential surface 36 and the tip outer circumferential surface 42 overlap, the tapered inner circumferential surface 37 and the tapered outer circumferential surface 43 overlap, and the basic inner circumferential surface 38 and the basic outer circumferential surface 44 overlap. Therefore, in the vicinity of the predetermined position P, the thickness of the main body portion 32 itself does not change, in other words, even if the shape of the main body portion 32 becomes thinner, the thickness remains constant. In addition, at a position where the outer diameter becomes thicker by the formation of the sublumen 41, a continuous inclined surface 45 is provided which is inclined continuously to the tapered outer circumferential surface 43 and continues to the basic outer circumferential surface 44.

[0038] The material of the main body 32 is not particularly limited, but a soft resin material is suitable, for example, fluororesins such as polytetrafluoroethylene (PTFE), ethylene-tetrafluoroethylene copolymer (ETFE), perfluoroalkoxy fluorine resin (PFA), etc., olefin resins such as polyethylene and polypropylene, or mixtures thereof, polyurethane, polyester, polyamide, polyether nylon resin, mixtures of olefin resins and ethylene-vinyl acetate copolymer, etc. The material of the soft tip 33 is also not particularly limited, but for example, a resin material such as polyurethane may be used.

[0039] In addition, the catheter 30 is preferably formed of a transparent material, so that the user can easily visually check the flashback of blood that has flowed into the main lumen 34 and the sub-lumen 41. The catheter 30 may be configured such that the material portion constituting the main lumen 34 is transparent and the material portion constituting the sub-lumen 41 is opaque. This is because the blood can be visually checked by the user as it flows around the gap 39. Conversely, the material portion constituting the sub-lumen 41 may be transparent and the material portion constituting the main lumen 34 may be opaque. In addition, even if the catheter assembly 10 is configured such that the inner needle 12 does not have a hole 14 (notch), blood flows into the main lumen 34 at the stage when the tip side of the inner needle 12 and the inner circumferential surface of the main lumen 34 of the catheter 30 are no longer in contact with each other as the catheter 30 advances relative to the inner needle 12, so that the flashback can be checked.

[0040] The base end of the catheter 30 is fixed to the tip end inside the catheter hub 50 by an appropriate fixing means such as crimping, fusion, adhesion, etc. The catheter hub 50 is exposed on the patient's skin with the catheter 30 inserted into the patient's blood vessel, and is left indwelling together with the catheter 30 by being affixed with tape or the like. The material constituting the catheter hub 50 is not particularly limited, and for example, the materials listed for the housing 20 may be appropriately adopted.

[0041] 1 and 2, catheter hub 50 has a main hub 51 (first catheter hub) formed in a cylindrical shape tapering toward the tip, and a sub-hub 52 (second catheter hub) connected to the side of main hub 51. Main hub 51 constitutes a main port through which one of two types of drugs flows in during infusion or the like, and sub-hub 52 constitutes a sub-port through which the other of the two types of drugs flows in.

[0042] The main hub 51 holds the catheter 30 fixedly at its tip, and has a main space 51a (first space) on the base end side of the fixed portion. The main space 51a communicates with the main lumen 34, and the inner needle 12 is inserted through it before puncture. A flow path 53 is provided inside the main hub 51, which communicates with the sub-lumen 41 of the catheter 30 and also communicates with a sub-space 52a in the sub-hub 52. The sub-space 52a and the flow path 53 form a communication passage 55 that communicates with the sub-lumen 41.

[0043] The sub-hub 52 is formed in a cylindrical shape having a sub-space portion 52a therein, and is provided above the main space portion 51a in accordance with the relative positions of the main lumen 34 and sub-lumen 41 of the catheter 30. This allows the main hub 51 to be easily manufactured in a shape in which the flow path 53 and the main space portion 51a are separated. In addition, it is possible to configure the housing 20 to be narrow in the width direction, allowing the user to easily grip and operate the housing 20 when puncturing.

[0044] The main hub 51 and the sub-hub 52 serve as connection parts to which a connector of an infusion tube can be connected (for example, a flange part 54 that protrudes radially outward is provided at the base end, or the inner peripheral surface of the main space part 51a or the sub-space part 52a is formed into a luer taper, etc.). Note that the main space part 51a of the main hub 51 and the sub-space part 52a of the sub-hub 52 may house a hemostatic valve (not shown) that prevents backflow of blood, and a plug (not shown) that penetrates the hemostatic valve when the connector of the infusion tube is inserted to allow infusion.

[0045] 1, the relative movement of the catheter 30 and catheter hub 50 between the inner needle 12 and the housing 20 is controlled by a catheter operating member 60. The catheter operating member 60 directly holds the catheter 30 and also houses and holds the catheter hub 50. This catheter operating member 60 has a operating plate portion 61 extending in the longitudinal direction of the housing 20, and a hub storage portion 62 connected to the base end of the operating plate portion 61 and storing the catheter hub 50.

[0046] The operation plate 61 is a portion where the user's fingers are placed to perform an advance / retract operation. A pair of side edges 61a of the operation plate 61 are disposed on the pair of rail portions 21a of the housing 20 and the upper surfaces of the pair of side walls 21 in the pre-puncture state. In addition, one or more catheter holding portions each consisting of a pair of protrusions (not shown) are provided along the longitudinal direction on the lower surface of the operation plate 61, and each of the portions grips the catheter 30.

[0047] 1 and 2, the multi-structure needle 11 (catheter 30) is supported at an intermediate axial position by a deflection suppression mechanism 90 composed of the above-mentioned support member 91 and operation plate portion 61. The support location by the support member 91 (deflection suppression mechanism 90) is located on the proximal side of the tapered outer circumferential surface 43 and the continuous inclined surface 45, and on the proximal side of the second side opening 41a. The support member 91 can support the catheter 30 in the vicinity of the second side opening 41a, which is closer to the distal end than the support member 91 and is closest to the distal end.

[0048] More specifically, the support member 91 can support the catheter 30 at a position 5 mm or less from the second side opening 41a, which is the closest to the support member 91 on the distal side. Here, the deflection suppression mechanism 90 is preferably provided as close to the distal end as possible from the viewpoint of suppressing deflection of the distal end side of the inner needle 12 and the catheter 30. On the other hand, the catheter 30 having the main lumen 34 and the sub-lumen 41 needs to have each opening provided at a certain distance so that the medicinal liquids discharged from each opening are mixed in the blood. However, if the deflection suppression mechanism 90 is provided on the distal side of the second side opening 41a, the deflection suppression mechanism 90 may come into contact with the catheter 30 near the second side opening 41a and cause damage, etc. Therefore, by providing the deflection suppression mechanism 90 at a distance close enough to mix the medicinal liquids discharged from each opening in the blood and near the second side opening 41a, it is possible to achieve both mixing in the blood and suppression of deflection.

[0049] The hub storage section 62 comprises an upper plate 63 connected to the operation plate section 61, and a pair of side plates (not shown) that form a storage chamber for storing the catheter hub 50. The upper plate 63 is cut out in a substantially isosceles triangular shape according to the shape of the catheter hub 50, and is provided with an arrangement hole 63a through which the sub-hub 52 protrudes. The hub storage section 62 separably holds the flange section 54 of the catheter hub 50 with an appropriate frictional force by the pair of side plates and an arch section 64 that bridges in an arc shape on the base end side.

[0050] 1 and 2, the guidewire 70 of the catheter assembly 10 is disposed in the hollow portion 12a of the inner needle 12 and extends along the axial direction of the inner needle 12. The guidewire 70 extends from a proximal end opening (not shown) of the inner needle 12 and is fixed to a guidewire operating member 80. The guidewire 70 is formed to be longer in the axial direction than the inner needle 12, and has appropriate rigidity and flexibility.

[0051] In the pre-puncture state, the tip of the guidewire 70 is disposed on the proximal side of the hole 14 of the inner needle 12. This allows blood that has flowed from the blood vessel into the hollow portion 12a when the inner needle 12 punctures the blood vessel to flow smoothly out of the inner needle 12 via the hole 14, allowing the user to visually confirm flashback. Then, in the puncture state of the inner needle 12, the guidewire 70 is advanced into the blood vessel by being advanced out of the tip opening 15a of the inner needle 12 under the operation of the guidewire operating member 80 by the user.

[0052] Returning to Fig. 1, the guidewire operating member 80 of the catheter assembly 10 has a retaining block 81 that fixedly holds the guidewire 70 on the base end side of the housing 20, and an operating arm 82 extending distally from the retaining block 81. The distal end of the operating arm 82 is provided with an operating protrusion 83 that is operated by a user through direct contact, and is slidably placed on the flat upper surface of the guidewire operating member 80. In other words, the retaining block 81 advances as the operating arm 82 is advanced, thereby pushing the guidewire 70 distally. The guidewire 70 is then delivered from the distal opening 15a of the inner needle 12 depending on the amount of advancement of the guidewire operating member 80.

[0053] The catheter assembly 10 according to the first embodiment is basically configured as described above, and its functions and effects will be described below.

[0054] As described above, the catheter assembly 10 is used when constructing an introduction portion for infusion into a patient. In use, a user grasps the housing 20 to insert the multi-structure needle 11 into the patient. At this time, the support member 91 of the housing 20 supports the basic outer peripheral surface 44 of the catheter 30 (the portion where the multiple lumens 31 extend) to ensure good linearity of the catheter 30. During puncture, the inner needle 12 is inserted first by cutting the skin and blood vessels with the blade surface 15, and then the catheter 30 is inserted into the body.

[0055] As shown in Fig. 2, the catheter 30 experiences sufficiently low piercing resistance when inserted because the sufficiently thin tip outer peripheral surface 42 is inserted first. In addition, the tip inner peripheral surface 36 including the soft tip 33 is in close contact with the inner needle 12 and does not bend radially inward. This also prevents the tip of the catheter 30 from shrinking in the axial direction, making it easy to insert the catheter 30. In particular, a thick inner needle 12 can be used for the main lumen 34, so that the catheter 30 is less likely to bend.

[0056] Furthermore, when the blood vessel is punctured, the tip of the guidewire 70 is located on the base end side of the hole 14, so that blood that has flowed into the hollow portion 12a of the inner needle 12 flows into the main lumen 34 (the gap 39 of the basic inner circumferential surface 38) of the catheter 30 through the hole 14. This allows the user to visually confirm the flashback of blood and confirm that the main lumen 34 has secured the blood vessel.

[0057] When the catheter 30 is further inserted, it moves from the predetermined position P to the tapered outer circumferential surface 43. At this time, the biological tissue spreads, but the catheter 30 can be smoothly inserted along the tapered outer circumferential surface 43, and even when it reaches the continuous inclined surface 45, the inclination allows the catheter 30 to continue to be smoothly inserted. In particular, since the sublumen 41 has a small diameter and the rate of change in the outer diameter of the basic outer circumferential surface 44 relative to the tip outer circumferential surface 42 is also small, the piercing resistance of the catheter 30 is greatly suppressed. Therefore, the catheter 30 can be smoothly inserted up to the basic outer circumferential surface 44.

[0058] When the multi-structure needle 11 has been inserted to a certain extent into the blood vessel, the user advances the guidewire operating member 80 to deliver the guidewire 70 from the distal end opening 15a of the inner needle 12. The user then advances the catheter operating member 60 to advance the catheter 30 and the catheter hub 50 along the guidewire 70. At this time, a gap 39 is formed between the basic inner circumferential surface 38 of the main lumen 34 and the inner needle 12, so that the sliding resistance between the inner needle 12 and the catheter 30 is low, and the catheter 30 can be moved smoothly relative to the inner needle 12.

[0059] Furthermore, when the multi-layer structure needle 11 is inserted to a certain extent into the blood vessel, blood flows into the sub-lumen 41 from the second side opening 41a. This allows the user to clearly recognize that the sub-lumen 41 has secured the blood vessel.

[0060] In particular, when the needle tip 13 of the inner needle 12 moves toward the base end side beyond the basic inner circumferential surface 38 of the catheter 30, the inner needle 12 can be easily retracted relative to the catheter 30. When the catheter 30 and the catheter hub 50 are delivered from the inner needle 12 and the housing 20, they are placed in the patient. When placed in the patient, an infusion tube is connected to each of the main hub 51 and the sub-hub 52. As a result, a first drug is administered to the patient via the main space 51a and the main lumen 34, and a second drug is administered to the patient via the sub-space 52a, the flow path 53, and the sub-lumen 41.

[0061] As described above, in the catheter assembly 10 according to the first embodiment, the distal inner circumferential surface 36 on the distal end side of the main lumen 34 is in close contact with the outer circumferential surface 16 of the inner needle 12, while the gap 39 is formed between the basic inner circumferential surface 38 on the proximal side of the distal inner circumferential surface 36 and the outer circumferential surface 16 of the inner needle 12. Therefore, at the position where the distal inner circumferential surface 36 is formed, the catheter 30 is reliably supported by the inner needle 12 even if it is compressed by biological tissue during puncture, and bending, shrinkage, etc. of the catheter 30 are suppressed. Therefore, the distal end of the catheter 30 is smoothly inserted into the body. In addition, the gap 39 of the basic inner circumferential surface 38 suppresses the sliding resistance between the catheter 30 and the inner needle 12, smoothing the relative movement of the inner needle 12 and the catheter 30, improving the operability when inserting and placing the catheter 30. Furthermore, the arrangement of the hole portion 14 allows the user to easily recognize that the blood vessel is secured. That is, the catheter assembly 10 allows the catheter 30 having multiple lumens 31 to be easily inserted, and enables various treatments such as administration of multiple types of medicines or blood sampling to be performed smoothly.

[0062] Furthermore, by forming an adhesive portion 35 between the tip inner circumferential surface 36 and the inner needle 12, the tip side of the catheter 30 can be formed with a thinner outer shape and is more reliably supported by the inner needle 12. This significantly improves the insertion performance of the catheter 30. Furthermore, since the tip outer circumferential surface 42 of the catheter 30 is thinner than the basic outer circumferential surface 44, it can be easily inserted into a blood vessel from the tip. Furthermore, the tapered outer circumferential surface 43 is inserted following the tip outer circumferential surface 42, and then the basic outer circumferential surface 44 is inserted, so that the thick basic outer circumferential surface 44 can be easily inserted.

[0063] Furthermore, when the catheter 30 having the soft tip 33 is inserted into a blood vessel, the soft tip 33 that comes into contact with the blood vessel wall easily bends and curves along the blood vessel, greatly reducing the occurrence of inflammation or damage to the blood vessel wall. In particular, since the tip inner peripheral surface 36 of the catheter 30 is supported by the inner needle 12, the occurrence of bending or contraction of the soft tip 33 during insertion before reaching the blood vessel can be effectively suppressed.

[0064] Furthermore, in the catheter assembly 10, the second side opening 41a of the sub-lumen 41 is located closer to the base end than the hole 14, so that the area near the tip of the catheter 30 can be made thinner, improving insertability. Also, blood flowing into the main lumen 34 can be quickly confirmed. The second side opening 41a of the sub-lumen 41 can prevent multiple types of drugs from immediately mixing together when they are administered into a blood vessel.

[0065] Furthermore, the catheter assembly 10 has a deflection suppression mechanism 90 (support member 91, holding portion of the catheter operating member 60) on the proximal side of the second side opening 41a. This can reduce the sliding resistance of the catheter 30 against the deflection suppression mechanism 90 when the catheter 30 is advanced. Furthermore, the deflection suppression mechanism 90 supports the catheter 30 on the proximal side of the tapered outer circumferential surface 43 and the continuous inclined surface 45 of the catheter 30. This can further reduce the sliding resistance of the catheter 30 against the deflection suppression mechanism 90 when the catheter 30 is advanced. Furthermore, by preventing the deflection suppression mechanism 90 from hitting and damaging the second side opening 41a or the tapered outer circumferential surface 43 and eliminating steps due to the second side opening 41a or the tapered outer circumferential surface 43 at the contact points and planned contact points of the deflection suppression mechanism 90, it is possible to prevent the inner needle 12 from bending with a constant force.

[0066] The present invention is not limited to the above-described embodiment, and various modifications are possible in accordance with the gist of the invention.

[0067] For example, in the above embodiment, an example has been described in which the guidewire 70 is used as an insertion assist mechanism that assists the insertion of the catheter 30. The insertion assist mechanism is not limited to this, and various configurations may be adopted. For example, the insertion assist mechanism may be configured to allow the guidewire 70 to be used later by exposing the base end opening of the inner needle 12 from the inner needle hub 19. Furthermore, the insertion assist mechanism may be configured to automatically retract the guidewire 70 exposed from the needle tip 13 into the hollow portion 12a. Alternatively, the catheter assembly 10 may be configured without including the guidewire 70 and the guidewire operating member 80.

[0068] The insertion assist mechanism may be configured to extend the guidewire 70 by more than twice the amount of manipulation of the guidewire manipulation member 80. For example, this type of structure may be configured such that the guidewire 70 is folded back inside the housing 20, and the guidewire manipulation member 80 advances and retreats this folded back portion.

[0069] The catheter assembly 10 may also be provided with a safety mechanism (not shown) for preventing accidental sticking of the inner needle 12 when the inner needle 12 is removed. For example, the safety mechanism may be a full cover type that protrudes a tubular member (telescope type, etc.) from the inner needle hub 19 and houses the inner needle 12 inside when the inner needle 12 is removed. The safety mechanism may also be a covering member that partially covers the needle tip 13 of the inner needle 12 and its surrounding area. Furthermore, the safety mechanism may be a type that automatically or manually retracts the inner needle 12 into the housing 20 (inner needle hub 19) when the inner needle 12 is removed.

[0070] Alternatively, the safety mechanism may be configured to cause a blunt needle having a tip that is less likely to pierce the skin to protrude from the needle tip 13 when the inner needle 12 is removed. If this blunt needle is configured to protrude from the needle tip 13 when the catheter 30 is advanced relative to the inner needle 12, it is also possible to prevent the inner needle 12 from piercing the catheter 30.

[0071] The catheter assembly 10 may be provided with a hemostatic mechanism (not shown) that prevents leakage of blood that has returned from the patient. For example, an example of the hemostatic mechanism is a hemostatic valve housed in the catheter hub 50. The hemostatic valve may be a cap type valve that is detachably attached to the base end of the catheter hub 50. Alternatively, the hemostatic mechanism may be an air vent member that is attached to a predetermined position (such as the base end) of the inner needle 12 and that is permeable to gas but not permeable to liquid.

[0072] The catheter assembly 10 may be provided with a catheter hub rotation mechanism (not shown) that enables the catheter hub 50 to rotate relative to the inner needle 12 in order to eliminate sticking of the catheter 30 to the inner needle 12 before puncture with the multi-structure needle 11. For example, the catheter hub rotation mechanism may be configured by forming a notch on at least one of the left and right directions at a position in the axial direction of the housing 20 and the catheter operating member 60 that corresponds to the sub-hub 52 in the pre-puncture state.

[0073] Furthermore, the catheter 30 may employ various mechanisms in addition to the flexibility mechanism provided by the soft tip 33. For example, a rigidity mechanism that prevents the catheter 30 from collapsing can be applied by embedding a ring-, mesh-, or coil-shaped reinforcing material, or a braid, or the like, in the catheter 30.

[0074] Furthermore, the catheter assembly 10 may employ an anti-kink mechanism (not shown) for preventing kinking of the catheter 30. For example, an anti-kink mechanism may be provided by making the distal end portion of the catheter hub 50 deformable.

[0075] In this embodiment, the catheter assembly 10 is configured with a separation mechanism (separate members) that separates the catheter hub 50 and the catheter operating member 60 when the catheter hub 50 is detached from the inner needle 12. However, the catheter assembly 10 may be configured so that the catheter hub 50 and the catheter operating member 60 are inseparable and can be placed together (non-separation mechanism).

[0076] Furthermore, the tip inner circumferential surface 36 of the main lumen 34 may have a smaller diameter than the basic inner circumferential surface 38, and may have a configuration in which the gap between the tip inner circumferential surface 36 and the outer circumferential surface 16 of the inner needle 12 is not zero (i.e., no tightly contacting portion 35 is formed). Even with this configuration, the inner needle 12 can satisfactorily support the catheter 30 pressed inwardly during puncture.

[0077] Other embodiments and configuration examples of the present invention will be described with reference to Figures 3 to 18. In the following description, the same components or components having the same functions are denoted by the same reference numerals, and detailed description thereof will be omitted. In the following embodiments and configuration examples, the mechanisms of the catheter assembly described above (insertion assist mechanism, safety mechanism, hemostasis mechanism, catheter hub rotation mechanism, flexibility mechanism, rigidity mechanism, kink prevention mechanism, separation mechanism, non-separation mechanism) can of course be appropriately adopted.

[0078] Second Embodiment 3, the catheter assembly 110 according to the second embodiment differs from the catheter assembly 10 according to the first embodiment in the structure of the multi-structure needle 111 (the inner needle 112 and the catheter 130). Specifically, in the catheter 130, the diameter of the sub-lumen 141 is formed to be larger than the diameter of the main lumen 134 through which the inner needle 112 is inserted and disposed, and the inner needle 112 is formed to be thin corresponding to this main lumen 134.

[0079] The inner needle 112 also has a groove 113 cut out from the blade face 15 toward the base end to a predetermined length as an introduction path for achieving blood flashback. The base end of the groove 113 communicates with a gap 139 defined by the outer circumferential surface 116 of the inner needle 112 and the inner circumferential surface of the main lumen 134 (basic inner circumferential surface 138).

[0080] Meanwhile, similarly to the first embodiment, the catheter 130 is composed of a main body portion 132 and a soft tip 133 (flexible portion) provided at the tip of the main body portion 132. However, the soft tip 133 is provided in a range from the tip of the main lumen 134 to a position slightly closer to the base end than the tip (second tip opening 141a) of the sub-lumen 141. A stylet 170 is disposed in the sub-lumen 141.

[0081] The main lumen 134 of the catheter 130 is provided with a tip inner circumferential surface 136 having a diameter approximately the same as the outer diameter of the inner needle 112, and a basic inner circumferential surface 138 which includes a tapered inner circumferential surface 137 and has a diameter slightly larger than the outer diameter of the inner needle 112 (the diameter of the tip inner circumferential surface 136). The tip inner circumferential surface 136 forms an intimate contact portion 135 with the outer circumferential surface 116 of the inner needle 112 other than the groove portion 113 (the gap is zero). The basic inner circumferential surface 138 forms a gap 139 with the outer circumferential surface 116 of the inner needle 112.

[0082] On the other hand, the sub-lumen 141 is located in the direction (upward) facing the blade surface 15. The sub-lumen 141 extends along the axial direction of the catheter 130 (parallel to the main lumen 134) and communicates with a second tip opening 141a provided at a position closer to the base end than the first tip opening 134a of the main lumen 134.

[0083] The outer peripheral surface of the catheter 130 has a tip outer peripheral surface 142 overlapping the tip inner peripheral surface 136, and a basic outer peripheral surface 144 having an outer diameter corresponding to the sub-lumen 141 at a position overlapping the basic inner peripheral surface 138. The tip of the basic outer peripheral surface 144 is continuous with an inclined end surface 145 inclined with respect to the axis of the catheter 130. A second tip opening 141a is formed in the inclined end surface 145, and the tip of the inclined end surface 145 is continuous with the base end of the tapered outer peripheral surface 143.

[0084] The stylet 170 disposed in the sub-lumen 141 is a solid rod-shaped member formed with a larger diameter than the inner needle 112, which gives stiffness to the entire catheter 130 and improves the insertion performance of the catheter 130 into a living body. The tip of the stylet 170 is inclined to the same extent as the inclined end surface 145 of the catheter 130, and is disposed slightly toward the base end side of the second tip opening 141a before puncture. This prevents biological tissue fragments from clogging the sub-lumen 141.

[0085] Moreover, stylet 170 extends within sub-lumen 141, and is inserted from sub-lumen 141 into sub-space portion 152a of sub-hub 152 connected to main hub 151 (catheter hub 150) via communication passage 153. The base end of stylet 170 is fixedly held by stylet holding member 171 attached to the protruding end of sub-hub 152. Therefore, when catheter 130 has been inserted into the blood vessel to a certain extent, the user can remove stylet 170 from catheter 130 by gripping stylet holding member 171.

[0086] An appropriate gap is provided between the outer surface of stylet 170 and the inner surface of sub-lumen 141, allowing stylet 170 to slide relative to catheter 130. Furthermore, blood flows into the gap between stylet 170 and sub-lumen 141, making it possible to know that the tip of sub-lumen 141 has been inserted into the blood vessel. The cross section of stylet 170 may have a similar, smaller shape to sub-lumen 141, but providing a groove makes it possible to more clearly confirm flashback. Moreover, stylet 170 may be made of a hollow transparent material, and this configuration also makes it possible to clearly confirm flashback.

[0087] As described above, the catheter assembly 110 according to the second embodiment can provide the same effects as the catheter assembly 10 according to the first embodiment. That is, the catheter 130 can be smoothly inserted into the body because its tip is supported by the outer circumferential surface 116 of the inner needle 112, thereby suppressing bending and shrinkage. In particular, if the inner needle 112 is formed thin, the wound on the patient when the inner needle 112 is inserted can be made smaller, making it easier to stop bleeding in the event of erroneous insertion.

[0088] Furthermore, the second tip opening 141a of the sub-lumen 141 facing the tip direction of the catheter 130 is prevented from being blocked by the blood vessel wall when the catheter is placed in the blood vessel. Therefore, blood can be satisfactorily aspirated from the second tip opening 141a of the sub-lumen 141. Furthermore, in the catheter assembly 110, the stylet 170 is detachably disposed in the sub-lumen 141, and thus the stylet 170 can improve the rigidity and straightness of the catheter 130.

[0089] Third Embodiment As shown in Fig. 4, the catheter assembly 210 according to the third embodiment differs from the catheter assemblies 10, 110 according to the first and second embodiments in the structure of the multi-structure needle 211 (catheter 230) and the catheter hub 250. Specifically, in a side cross-sectional view of the catheter 230, a main lumen 234 through which the inner needle 12 is inserted and disposed is provided above the sub-lumen 241. In addition, in the third embodiment, the diameter of the main lumen 234 (basic inner circumferential surface 238) is formed larger than the diameter of the sub-lumen 241. Note that the main body and soft tip (flexible part) constituting the catheter 230 have the same configuration as in the second embodiment, and the soft tip is provided in the range from the tip of the catheter 230 to the basic outer circumferential surface 244.

[0090] The main lumen 234 of the catheter 230 has a tip inner peripheral surface 236 and a basic inner peripheral surface 238 including a tapered inner peripheral surface 237, similar to the main lumen 34 of the first embodiment. The outer peripheral surface of the catheter 230 has a tip outer peripheral surface 242, a tapered outer peripheral surface 243, and a basic outer peripheral surface 244, and the sub-lumen 241 extends from the basic outer peripheral surface 244 to the range where the tapered outer peripheral surface 243 and the tip outer peripheral surface 242 are formed. The sub-lumen 241 is provided downward on the opposite side to the direction in which the blade surface 15 of the inner needle 12 faces. The second tip opening 241a of the sub-lumen 241 is disposed at approximately the same position in the axial direction as the first tip opening 234a of the main lumen 234.

[0091] For this reason, the outer shape of the catheter 230 becomes thicker overall, but the lower side of the first tip opening 234a at the tip (the side where the sub-lumen 241 is formed) is formed into an inclined end surface 245 that continues to the tapered tip portion 40. The inclined end surface 245 is inclined at an appropriate angle below the blade surface 15 of the inner needle 12, thereby facilitating insertion of the tip (tip outer peripheral surface 242) of the catheter 230. The second tip opening 241a is provided on this inclined end surface 245. In addition, although not shown, by making the inner diameter of the tip portion of the sub-lumen 241 smaller, it is possible to more effectively and smoothly insert the tip of the catheter 230.

[0092] Meanwhile, the main hub 251 of the catheter hub 250 forms a first space 251a so as to communicate with the main lumen 234 at the upper part of the catheter 230. The main hub 251 also has a bypass communication passage 253 that communicates between the sub-lumen 241 provided on the lower side of the catheter 230 and a second space 252a of the sub-hub 252 connected to the upper side of the main hub 251. The bypass communication passage 253 is provided so as to wrap around within the peripheral wall surrounding the first space 251a of the main hub 251, and communicates with the second space 252a.

[0093] As described above, the catheter assembly 210 according to the third embodiment can also provide the same effects as the catheter assembly 10. In particular, in the catheter assembly 210, the second tip opening 241a of the sub-lumen 241 is located closer to the tip side than the hole 14 of the inner needle 12, making it possible to quickly confirm that blood has flowed into the sub-lumen 241.

[0094] [Fourth embodiment] As shown in Fig. 5, the catheter assembly 310 according to the fourth embodiment differs from the catheter assemblies 10, 110, 210 according to the first to third embodiments in the structures of the multi-layered needle 311 (catheter 330) and the catheter hub 350. Specifically, in a plan cross-sectional view of the catheter 330, the sub-lumens 341 are adjacent to each other in the lateral direction (to the right in Fig. 5) of the main lumen 334 and extend parallel to each other. The inner needle 12 is inserted and disposed in the main lumen 334, while the guidewire 70 is slidably disposed in the sub-lumen 341.

[0095] In the fourth embodiment, the diameter of the main lumen 334 is set to be larger than the diameter of the sub-lumen 341. The main body and soft tip (flexible part) constituting the catheter 330 have the same configuration as in the second embodiment, and the soft tip is provided in the range from the tip of the catheter 330 to the basic outer circumferential surface 344.

[0096] The main lumen 334 of the catheter 330, like the main lumen 34 of the first embodiment, communicates with a tip opening 334a and has a tip inner circumferential surface 336 and a basic inner circumferential surface 338 including a tapered inner circumferential surface 337. In addition, the outer circumferential surface of the catheter 330 has a tip outer circumferential surface 342, a tapered outer circumferential surface 343, and a basic outer circumferential surface 344.

[0097] Sub-lumen 341 is provided at a location where basic outer circumferential surface 344 is formed. The diameter of sub-lumen 341 is set to an appropriate dimension according to the outer diameter of guidewire 70. At the tip of basic outer circumferential surface 344, inclined end surface 345 continuing to tapered outer circumferential surface 343 is formed, and second tip opening 341a is formed in inclined end surface 345.

[0098] On the other hand, catheter hub 350 has a main hub 351 and a sub-hub 352, and the sub-hub 352 is connected to the side of the main hub 351. This main hub 351 has a first space 350a that communicates with the main lumen 334, and also has a communication passage 353 that communicates with a second space 352a of the sub-hub 352. That is, the guidewire 70 is slidably inserted into the sub-lumen 341 via the second space 352a and the communication passage 353.

[0099] As described above, the catheter assembly 310 according to the fourth embodiment can also provide the same effects as the catheter assembly 10. In particular, the catheter assembly 310 has the guidewire 70 slidably disposed in the sub-lumen 341, whereby the guidewire 70 reinforces the catheter 330 when the multi-structure needle 311 is inserted, thereby improving the insertion performance of the catheter 330. Furthermore, the guidewire 70 can be inserted into a blood vessel from the sub-lumen 341 to provide good guide for the insertion of the catheter 330.

[0100] The arrangement of the main lumen and the sub-lumen is not particularly limited in the above-mentioned catheter assemblies 10, 110, 210, 310 and the catheter assemblies 510, 610, 710, 810, 910, 1010 described below. In other words, any of the arrangements of the main lumen α and the sub-lumen β in the catheters 430A to 430F according to the first to sixth configuration examples shown in Figures 6A to 6F can be adopted.

[0101] Specifically, the catheter 430A shown in Fig. 6A has the same arrangement relationship between the main lumen 34 and the sub-lumen 41 as described in the first embodiment. That is, the diameter of the main lumen α is larger than the diameter of the sub-lumen β, and the sub-lumen β is disposed above the main lumen α. The cross-sectional shape perpendicular to the axial direction of the catheter 430A may be a shape other than the elliptical shape shown in Fig. 6A, and may be formed into, for example, a perfect circle. The same applies to the other catheters 430B to 430F.

[0102] The positions of the main lumen α and the sub-lumen β will be described using the blade surface 15 of the inner needle 12 arranged in the main lumen α as an index. That is, as described above, the blade surface 15 of the inner needle 12 is oriented so as to face upward when the patient's body surface is placed downward during puncture. Therefore, the presence of the sub-lumen β above the main lumen α means that the sub-lumen β is located in the upward direction facing the blade surface 15 in the circumferential direction of the catheter 430A.

[0103] The catheter 430A shown in Fig. 6A can check for flashback by using the sub-lumen β. In addition, this catheter 430A prevents the formation of the tip (inclined end surface) of the sub-lumen β from getting caught on the vascular wall on the opposite side of the insertion site in the blood vessel and hindering movement when inserted into the blood vessel. Therefore, inflammation and damage to the vascular wall can be prevented. Furthermore, the second tip opening of the sub-lumen β can be prevented from being closed by the vascular wall and reducing the flow rate.

[0104] The catheter 430B shown in Fig. 6B has the same arrangement relationship between the main lumen 334 and the sub-lumen 341 as described in the fourth embodiment. That is, the diameter of the main lumen α is larger than the diameter of the sub-lumen β, and the sub-lumen β is arranged laterally of the main lumen α (in a direction perpendicular to the direction in which the blade surface 15 faces) in the circumferential direction of the catheter 430B. With this configuration, it is possible to obtain the same effect as the arrangement relationship shown in Fig. 6A, and furthermore, flashback of the main lumen α can be easily confirmed.

[0105] The catheter 430C shown in Fig. 6C has the same arrangement relationship as that of the main lumen 234 and sub-lumen 241 described in the third embodiment. That is, the diameter of the main lumen α is larger than the diameter of the sub-lumen β, and the sub-lumen β is disposed below the main lumen α in the circumferential direction of the catheter 430C (the opposite direction to the direction in which the blade surface 15 faces). With this configuration, it becomes possible to more clearly check for flashback of the main lumen α.

[0106] The catheter 430D shown in FIG. 6D has the same arrangement relationship between the main lumen 134 and the sub-lumen 141 as described in the second embodiment. That is, the diameter of the main lumen α is smaller than the diameter of the sub-lumen β, and the sub-lumen β is arranged on the upper side of the main lumen α in the circumferential direction of the catheter 430D. Also, the catheter 430E shown in FIG. 6E has the diameter of the main lumen α smaller than the diameter of the sub-lumen β, and the sub-lumen β is arranged in the lateral direction of the main lumen α. Furthermore, the catheter 430F shown in FIG. 6F has the diameter of the main lumen α smaller than the diameter of the sub-lumen β, and the sub-lumen β is arranged on the lower side of the main lumen α. The catheters 430D to 430F shown in FIG. 6D to FIG. 6F can also obtain sufficient effects, similar to the above-mentioned catheters 430A to 430C.

[0107] 6A to 6F, the cross-sectional shapes of the main lumen α and the sub-lumen β are formed into a perfect circle, but the cross-sectional shapes of these lumens are not particularly limited. As an example, the lumen with a smaller flow passage cross-sectional area (e.g., the sub-lumen) may be formed into a shape (C-shape, U-shape, ellipse, polygonal shape, etc.) that surrounds a part of the circumferential outer side of the main lumen α. This allows the outer diameter of the entire catheters 430A to 430F to be smaller.

[0108] Also, like catheters 430G and 430H according to seventh and eighth configuration examples shown in Fig. 7A and Fig. 7B, the catheter assembly may have three or more lumens 431. Specifically, the catheter 430G shown in Fig. 7A has first and second sublumens β1 and β2 arranged side by side in the width direction (direction perpendicular to the direction in which the blade surface 15 faces) above the main lumen α. The catheter 430H shown in Fig. 7B has the main lumen α arranged at the axial center of the catheter 430H, the first sublumen β1 arranged above it (the direction in which the blade surface 15 faces), and the second sublumen β2 arranged below it (the opposite direction to the direction in which the blade surface 15 faces).

[0109] Furthermore, the catheter assembly may be configured so that flashback can be confirmed in the order of the main lumen α and then the sub-lumen β by appropriately setting the diameter and length of each flashback flow path. This allows the flashback of the lumen with an opening at the tip to be confirmed first, making it less likely that the user will feel uncomfortable. Alternatively, the catheter assembly may be configured so that flashback can be confirmed in the order of the sub-lumen β and then the main lumen α by appropriately setting the diameter and length of each flashback flow path. This makes it easier to use for a user who assumes that if the sub-lumen β is in a blood vessel, then the main lumen α is in the blood vessel.

[0110] Fifth embodiment 8 to 10, a catheter assembly 510 according to the fifth embodiment includes a catheter 530 having three lumens 531, similar to the seventh and eighth configuration examples, and is configured to be able to support a multi-structure needle 511 by a bending suppression mechanism 590 of an inner needle hub 519. In detail, in a side cross-sectional view along the axial direction, the catheter 530 has a main lumen 534 disposed on the lower side, a first sub-lumen 540 in the middle, and a second sub-lumen 545 disposed on the upper side.

[0111] The inner needle hub 519 of the catheter assembly 510 has a pair of extending portions 520 that branch into two from a base portion 521 at the center in the width direction. This inner needle hub 519 holds the catheter hub 550 in a state where it is exposed at the top and bottom. The inner needle hub 519 may be made into a housing by attaching a cover to the lower or upper sides of the pair of extending portions 520. When attaching a cover to the upper side, it is preferable to provide a slit in the upper cover so that the tab can be exposed from the housing and operated.

[0112] The deflection suppression mechanism 590 has a pair of openable and closable support arms 591, and a restraining portion 592 capable of restraining the pair of support arms 591 in a closed state and capable of releasing the restraint. The pair of support arms 591 are pivotally supported by a pair of support pins 593, and can be opened and closed in the left-right direction relative to a pair of extending portions 520 of the inner needle hub 519.

[0113] Each support arm 591 is provided with a support groove 591a for holding the inner needle 12 in the closed state. The pair of support grooves 591a constitute a support hole 594 for supporting the multi-structure needle 511. In the initial state of the catheter assembly 510, the wall surface constituting the support hole 594 functions as a sliding contact support part 595 that rubs against the catheter 530 when the catheter 530 advances relative to the inner needle 12. In the pre-puncture state, a slight gap is formed between the outer surface of the catheter 530 and the inner surface of the sliding contact support part 595. Moreover, the sliding contact support part 595 surrounds the entire circumferential circumference of the catheter 530 in a contactable manner.

[0114] Each support arm 591 is provided with a curved engagement groove 591b when viewed from the front in the closed state. Meanwhile, restraining portion 592 has a head portion 592a corresponding to the shape of a pair of engagement grooves 591b connected together, and engages with each other in the pre-puncture state to close each support arm 591. As catheter hub 550 advances, restraint on the pair of support arms 591 is released by being pushed by catheter hub 550.

[0115] Meanwhile, the main lumen 534, the first sublumen 540, and the second sublumen 545 extend parallel to each other inside the catheter 530. Furthermore, on the tip side of the catheter 530, the main lumen 534, the first sublumen 540, and the second sublumen 545 are stacked in a stepped manner.

[0116] Specifically, the main lumen 534 is formed longer than the first and second sublumens 540, 545, and communicates with a first distal end opening 534a (main opening) at the tip of the catheter 530 and a first proximal end opening (not shown) at the most proximal end of the catheter 530. The catheter 530 also has a first tapered outer circumferential surface 535 whose outer diameter gradually decreases toward the first distal end opening 534a. A first side opening 534b (main opening) communicating with the main lumen 534 is provided at a midpoint of the catheter 530 (between the first tapered outer circumferential surface 535 and a second distal end opening 540a described later).

[0117] The first sub-lumen 540 is formed shorter than the main lumen 534 and longer than the second sub-lumen 545. Here, the thickness (outer diameter) of the distal end side of the catheter 530 is increased by overlapping the first sub-lumen 540 with the main lumen 534, and the distal end of the first sub-lumen 540 has a second tapered outer circumferential surface 541 (tapered portion) constituting a step portion. The first sub-lumen 540 communicates with a second distal end opening 540a (sub-opening) formed in the second tapered outer circumferential surface 541. The first sub-lumen 540 also communicates with a second base end opening (not shown) at the most proximal end of the catheter 530 (located coaxially with the first base end opening). A second side opening 540b (sub-opening) communicating with the first sub-lumen 540 is provided between the second tapered outer circumferential surface 541 of the catheter 530 and a third distal end opening 545a described later.

[0118] The second sub-lumen 545 is formed to be the shortest. The tip side of the catheter 530 is further increased in thickness (outer diameter) by overlapping the main lumen 534 and the first sub-lumen 540 with the second sub-lumen 545, and the tip of the second sub-lumen 545 has a third tapered outer circumferential surface 546 (tapered portion) constituting a step portion. The second sub-lumen 545 communicates with a third tip opening 545a (sub-opening) formed in the third tapered outer circumferential surface 546. The second sub-lumen 545 also communicates with a third base end opening (not shown) at the very base end of the catheter 530 (located coaxially with the first base end opening). A third side opening 545b (sub-opening) communicating with the second sub-lumen 545 is provided on the base end side of the third tapered outer circumferential surface 546 of the catheter 530.

[0119] The first side opening 534b and the second tip opening 540a are spaced apart by 17 mm or more. Similarly, the second side opening 540b and the third tip opening 545a are spaced apart by 17 mm or more.

[0120] In this embodiment, the sliding support portion 595 of the deflection suppression mechanism 590 is located on the proximal side of the third side opening 545b of the catheter 530 in the pre-puncture state. More specifically, the sliding support portion 595 is provided so as to be able to support a position near the third side opening 545b, which is the sub-opening most proximal of the two sublumens 540, 545 (for example, 5 mm or less toward the proximal side).

[0121] In the initial state of the catheter assembly 510, the sliding support portion 595 may be provided on the distal side of the third distal opening 545a of the second sublumen 545 (see the two-dot chain line in FIG. 9). Specifically, the sliding support portion 595 is capable of supporting the base end side of the second distal opening 540a (the sub-opening closest to the distal end of the two sublumens 540, 545). Even in this configuration in which the deflection suppression mechanism 590 supports the distal side of the third distal opening 545a, damage to the second distal opening 540a and the second tapered outer circumferential surface 541 of the first sublumen 540 can be suppressed, and the effect of suppressing deflection of the inner needle 12 is improved.

[0122] The catheter hub 550 of the catheter assembly 510 has a main hub 551 that functions as a port for the main lumen 534. The catheter hub 550 further has a first sub-port 552 that functions as a port for the first sub-lumen 540, and a second sub-port 553 that functions as a port for the second sub-lumen 545. A hub operating part 551a on which a user places his / her finger is provided at the tip of the main hub 551, and this hub operating part 551a has a surface that pushes out the above-mentioned restraint part 592. The hub operating part 551a may be configured to be detachable from the main hub 551.

[0123] Each of the first and second sub-ports 552, 553 has a connecting portion of the main hub 551, a soft flexible tube 554 (soft portion) fixed to the connecting portion, and a sub-hub 555 connected to a base end of the flexible tube 554. The sub-hub 555 is configured as a connector to which a medical device is connected. A first communication passage 552a communicating with the first sub-lumen 540 is formed inside the first sub-port 552 (main hub 551, flexible tube 554, sub-hub 555). Similarly, a second communication passage 553a communicating with the second sub-lumen 545 is formed inside the second sub-port 553.

[0124] The catheter assembly 510 according to the fifth embodiment is basically configured as described above. In the catheter assembly 510, when the multi-structure needle 511 is inserted, the bending suppression mechanism 590 supports the position near the base end of the third lateral opening 545b. Therefore, bending of the inner needle 12 can be effectively suppressed and the multi-structure needle 511 can be inserted.

[0125] After the multi-layered needle 511 has punctured the catheter, the user advances the catheter hub 550 to advance the catheter 530 relative to the inner needle 12, as shown in Fig. 10. At this time, the deflection suppression mechanism 590 supports the base end side of the third lateral opening 545b of the second sublumen 545, so that the catheter 530 can be advanced smoothly without getting caught. In addition, the catheter hub 550 pushes out the restraining portion 592 when advancing, thereby opening the pair of support arms 591 in the left and right directions. This allows the support of the multi-layered needle 511 by the deflection suppression mechanism 590 to be easily released, and the catheter 530 and the catheter hub 550 to be detached from the inner needle 12.

[0126] In this way, the catheter assembly 510 can also provide the same effects as the catheter assembly 10. For example, when the catheter 530 is placed, the catheter assembly 510 can easily supply medicinal liquids and blood to the main lumen 534 and the first and second sub-lumens 540, 545 by connecting medical devices to the main hub 551 and sub-hub 555. Furthermore, after the catheter 530 is placed, different types of medicinal liquids can be smoothly flowed and administered into a blood vessel by the main lumen 534 and the first and second sub-lumens 540, 545, which extend parallel to each other.

[0127] Furthermore, even in a configuration in which the catheter assembly 510 has multiple lumens, namely the main lumen 534 and the first and second sub-lumens 540, 545, the deflection suppression mechanism 590 supports the base end side of the second tip opening 540a (the most distal sub-opening). This makes it possible to suppress deflection of the inner needle 12 while also reducing damage to the catheter 530.

[0128] That is, in order to suppress bending of the inner needle 12, it is preferable that the bending suppression mechanism 590 supports a portion of the inner needle 12 close to the needle tip 13, but if the bending suppression mechanism 590 is configured to support the tip side beyond the multiple sub-openings, there is a higher possibility that the catheter 530 will come into contact with the sub-openings during movement and be damaged. In contrast, the catheter assembly 510 according to this embodiment can achieve both prevention of bending of the inner needle 12 and mobility of the catheter by appropriately arranging the formation positions of the sub-openings and the support position of the bending suppression mechanism 590.

[0129] Moreover, in this catheter assembly 510, the deflection suppression mechanism 590 supports the proximal side of the third side opening 545b (the sub-opening located most proximal side), which makes it possible to more reliably prevent damage to the catheter 530. Furthermore, since the deflection suppression mechanism 590 supports the proximal side of the third tapered outer circumferential surface 546, it is possible to prevent the deflection suppression mechanism 590 from getting caught on the third tapered outer circumferential surface 546. Therefore, it is possible to further improve the mobility of the catheter 530.

[0130] In addition, since the sub-opening of the catheter assembly 510 includes the second and third lateral openings 540b, 545b, the medicinal liquid and blood that have flowed through the first and second sublumens 540, 545 can be effectively discharged into the blood vessel. Moreover, since the bending suppression mechanism 590 is located closer to the base end than the third lateral opening 545b, damage near the third lateral opening 545b is also suppressed.

[0131] Here, in the catheter assembly 510, the distance between the first tip opening 534a and the second tip opening 540a is 17 mm or more, so that the medicinal liquid flowing out from the first tip opening 534a and the medicinal liquid flowing out from the second tip opening 540a can be mixed in the blood vessel. In other words, incompatible drugs can be administered well with one catheter 530.

[0132] Furthermore, in the catheter assembly 510, the bending suppression mechanism 590 can support a position 5 mm or less on the proximal end side of the third lateral opening 545b, thereby shortening the distance from the needle tip 13 of the inner needle 12 to the bending suppression mechanism 590. Therefore, bending of the inner needle 12 can be more firmly suppressed.

[0133] Furthermore, the catheter assembly 510 can reliably prevent the inner needle 12 from moving up and down and left and right (such as deviation from the bending suppression mechanism 590 or bending of the inner needle 12) by using the bending suppression mechanism 590 that surrounds the entire circumferential circumference of the catheter 530.

[0134] Furthermore, the catheter assembly 510 includes the first and second sub-ports 552, 553 each including a sub-hub 555 and a flexible tube 554, so that the sub-hub 555 can be freely positioned and oriented. This allows the user to easily insert the multi-structure needle 511 and the catheter 530.

[0135] The main opening through which the main lumen 534 communicates and the sub-openings through which the first and second sub-lumens 540 and 545 communicate are not limited to the above configurations (first tip opening 534a, first side opening 534b, second tip opening 540a, second side opening 540b, third tip opening 545a, third side opening 545b), and various configurations may be adopted. For example, the main opening may be composed of only the first tip opening 534a.

[0136] The sub-opening of the first sub-lumen 540 may be either the second tip opening 540a or the second side opening 540b. Similarly, the sub-opening of the second sub-lumen 545 may be either the third tip opening 545a or the third side opening 545b.

[0137] For example, when the sub-openings of the first and second sublumens 540 and 545 are respectively configured with only the second side opening 540b and the third side opening 545b, the second tapered outer circumferential surface 541 and the third tapered outer circumferential surface 546 form a step portion of the blocked catheter 530. In this configuration, the deflection suppression mechanism 590 may be configured to support the second tapered outer circumferential surface 541 or the third tapered outer circumferential surface 546 near the base end. This is because, even with this configuration, it is possible to effectively avoid the deflection suppression mechanism 590 from getting caught on the second tapered outer circumferential surface 541 or the third tapered outer circumferential surface 546.

[0138] Moreover, the deflection suppression mechanism 590 may also employ various configurations, and for example, the inner surface of the support hole 594 constituting the sliding support portion 595 may be formed in a tapered shape tapering toward the tip. This makes it possible to reduce the catching of the third tapered outer peripheral surface 546 on the sliding support portion 595 even in a configuration having a tapered portion (e.g., the third tapered outer peripheral surface 546) like the catheter 530 and having the sliding support portion 595 on its tip side.

[0139] It goes without saying that the configuration of the sub-lumen in the catheter 530 (including the tapered portion) and the configuration of the bending suppression mechanism 590 can also be applied to the embodiments described later.

[0140] Sixth Embodiment 11, 12A and 12B, a catheter 630 of a catheter assembly 610 according to the sixth embodiment has a main lumen 634 and a sub-lumen 641 disposed above and below, and the two lumens are partitioned by a partition wall 640. The partition wall 640 is configured to be deformable in response to the pressure of the main lumen 634 and the sub-lumen 641.

[0141] Specifically, the main lumen 634 of the catheter 630 communicates with a tip opening 634a formed at the tip of the catheter 630, and also communicates with a base end opening (not shown) formed at the base end of the catheter 630. In the pre-puncture state, the inner needle 12 is detachably disposed in this main lumen 634.

[0142] The sub-lumen 641 of the catheter 630 is located below the main lumen 634 and extends parallel to the main lumen 634. The sub-lumen 641 communicates with a side opening 641a formed in the middle of the lower side of the catheter 630.

[0143] The partition 640 extends along the axial direction of the catheter 630, and separates the main lumen 634 from the sub-lumen 641. The partition 640 is connected to a position that is out of phase with the tubular wall portion 639 of the catheter 630 by approximately 180° in a cross-sectional view perpendicular to the axial direction of the catheter 630, but is formed to be longer (with a margin) than the diameter of the tubular wall portion 639. Moreover, the partition 640 is configured to be more flexible than the tubular wall portion 639, and can be deformed when it receives a positive pressure of a predetermined level or more from the medicinal solution.

[0144] 12A, for example, the partition 640 can expand downward to favorably position the inner needle 12 with the inner needle 12 inserted into the main lumen 634. Also, for example, as shown in Fig. 12B, when a large amount of medicinal liquid is caused to flow through the main lumen 634, the partition 640 increases the flow path cross-sectional area of ​​the main lumen 634. On the other hand, when a large amount of medicinal liquid is caused to flow through the sub-lumen 641, the partition 640 increases the flow path cross-sectional area of ​​the sub-lumen 641 as shown by the two-dot chain line in the illustrated example.

[0145] Returning to Fig. 11, in the catheter assembly 610, the base end of the catheter 630 is fixed and held by a catheter hub 650. This catheter hub 650 has a sub-hub 652 that protrudes upward from a main hub 651, similar to the first embodiment.

[0146] The catheter operating member 660 is formed as a long plate corresponding to the long inner needle 12 and the catheter 630 (multi-structure needle 611), and is rotatably fixed to the catheter hub 650. The catheter operating member 660 has a pressing portion 661 that can press against a portion between the base end and the tip end of the catheter 630. The pressing portion 661 constitutes a part of the bending suppression mechanism 690. The catheter operating member 660 also has a plurality of anti-slip ribs 662 provided at intervals on its upper surface.

[0147] The housing 620 of the catheter assembly 610 is formed in a long, narrow bowl shape, and houses the base end side of the multi-structure needle 611 and also movably houses the catheter hub 650. The housing 620 has a bottom plate 621 and left and right side walls 622 extending upward from both the left and right sides of the bottom plate, and is open at the top and tip side. The tip of the bottom plate 621 is a sliding contact support part 691 that rubs against the catheter 630 when the catheter 630 advances relative to the inner needle 12.

[0148] The sliding support portion 691, together with the pressing portion 661, constitutes a deflection suppression mechanism 690. The deflection suppression mechanism 690 is capable of supporting the inner needle 12 and the catheter 630 (multiple structure needle 611) between the sliding support portion 691 and the pressing portion 661 when the catheter 630 advances relative to the inner needle 12. The sliding support portion 691 is disposed at a position capable of supporting the base end side of the catheter 630 relative to the lateral opening 641a in the pre-puncture state.

[0149] The catheter assembly 610 according to the sixth embodiment is basically configured as described above. When using the catheter assembly 610, the user presses the tip of the catheter operating member 660 with the index finger of one hand, while pressing the tip of the catheter assembly 610 (the tip of the catheter 630 through which the inner needle 12 is inserted) against the patient to perform puncture. With the catheter operating member 660 (pressing portion 661) pressing against an intermediate portion of the catheter 630, the catheter 630 is supported by being sandwiched between the pressing portion 661 and the tip of the housing 620 (sliding support portion 691). As a result, bending of the multi-structure needle 611 is suppressed.

[0150] Then, the catheter manipulation member 660 advances relative to the inner needle 12 and the housing 620, thereby inserting the tip of the catheter 630 to the target position in the blood vessel. When the catheter 630 moves in the distal direction relative to the inner needle 12, the catheter 630 slides against the sliding support portion 691. Thereafter, while holding the catheter manipulation member 660 with the other hand, the housing 620 is pulled in the proximal direction. This causes the inner needle 12 to detach from the catheter hub 650, and by removing the catheter manipulation member 660, the catheter 630 and the catheter hub 650 can be placed in the patient.

[0151] The above catheter assembly 610 can obtain the same effects as the other embodiments described above. That is, the bending suppression mechanism 690 supports a position near the base end side (for example, a base end position within 5 mm) of the side opening 641a (the most distal sub-opening) of the sub-lumen 641. This makes it possible to reduce damage to the catheter 630 while suppressing bending of the inner needle 12.

[0152] In particular, in this catheter assembly 610, the main lumen 634 and the sub-lumen 641 are separated by a partition wall 640 that is deformable in response to pressure, so that the main lumen 634 can be enlarged in the pre-puncture state, simplifying the relative movement of the inner needle 12 and the catheter 630. The partition wall 640 is appropriately deformed by the flow pressure when a drug or blood is administered. For example, even when a relatively large amount of drug solution in the sub-lumen 641 is caused to flow compared to the drug solution in the main lumen 634, it is possible to easily ensure the flow path cross-sectional area.

[0153] Seventh embodiment 13, a catheter 730 of a catheter assembly 710 according to the seventh embodiment is configured similarly to the catheter 30 of the first embodiment, and has therein a main lumen 734 and a sub-lumen 741. A bending suppression mechanism 790 for suppressing bending of the inner needle 12 and the catheter 730 (multiple-structure needle 711) is provided on the tip side of the catheter assembly 710.

[0154] Specifically, the inner needle hub 719 has an upper housing 720 and a lower housing 721, and in a pre-puncture state, the upper housing 720 and the lower housing 721 are stacked vertically. The respective tip portions 720a, 721a of the upper housing 720 and the lower housing 721 are held by a guidewire operating member 780, which will be described later, so that the expansion in the vertical direction is restricted. A slit 722 extending in the longitudinal direction is formed between the upper housing 720 and the lower housing 721 on the left and right side portions of the inner needle hub 719. The upper housing 720 has a pair of side gripping portions 720b inclined obliquely with respect to the slit 722, and the pair of side gripping portions 720b are gripped by the user when the multi-structure needle 711 is punctured.

[0155] The deflection suppression mechanism 790 is composed of a tip portion 720a of the upper housing 720 and a tip portion 721a of the lower housing 721. A holding groove 723 having a semicircular cross section is formed on the opposing surfaces of the tip portions 720a, 721a of the upper housing 720 and the lower housing 721. A hole-shaped sliding contact support portion 791 that rubs against the catheter 730 when the catheter 730 advances relative to the inner needle 12 is formed by the wall portion that constitutes the holding groove 723. In the initial state of the catheter assembly 710, a small gap is formed between the outer surface of the catheter 730 and the sliding contact support portion 791.

[0156] The catheter 730 has a tip opening 734a at its tip that communicates with the main lumen 734, and has a side opening 741a of a sub-lumen 741 at a position spaced a predetermined distance (for example, 17 mm or more) from the tip opening 734a. The catheter 730 is fixedly held by a catheter hub 750.

[0157] The catheter hub 750 includes a main hub 751 that communicates with the main lumen 734, and a sub-port 752 provided on a side surface of the main hub 751. In this case, the sub-port 752 has a sub-hub 753 to which a medical device can be connected, a hard tube 754 that is connected to the main hub 751 and protrudes to the outside of the inner needle hub 719, and a soft tube 755 (soft tube) that extends between the hard tube 754 and the sub-hub 753 and is softer than the hard tube 754. The sub-port 752 is exposed to the outside via a slit 722 in the inner needle hub 719, with the hard tube 754 of the main hub 751 protruding laterally.

[0158] A catheter operating member 760 is attached to the catheter hub 750 on the proximal side of the sub-port 752. The catheter operating member 760 has a central base 761 detachably connected to the proximal end of the catheter hub 750, and a pair of finger hooks 762 extending on both left and right sides from the central base 761. In the pre-puncture state, the central base 761 is housed within the inner needle hub 719, and the finger hooks 762 protrude outward in the left and right direction through the slits 722.

[0159] In the catheter assembly 710, in the pre-puncture state, the deflection suppression mechanism 790 (sliding contact support portion 791) is located on the base end side of the side opening 741a of the sub-lumen 741. The sliding contact support portion 791 is provided on the base end side of the side opening 741a located on the most distal side.

[0160] The guidewire 770 extends in the axial direction within the inner needle 12, protrudes from a proximal end opening (not shown) of the inner needle 12, and is connected to a proximal end of a guidewire operating member 780 via a connecting part (not shown) disposed within the inner needle hub 719. The guidewire operating member 780 is provided so as to be displaceable in the front-to-rear direction relative to the inner needle hub 719. The guidewire operating member 780 also has a pair of restraining arms 781 that hold the tip end of the inner needle hub 719 in the pre-puncture state. The guidewire operating member 780 also has a tab 782 for hanging fingers and a plurality of ribs 783 for preventing slipping.

[0161] When using the catheter assembly 710 configured as above, a user inserts the multi-structure needle 711 (inner needle 12, catheter 730) into a patient. At this time, the bending suppression mechanism 790 supports the multi-structure needle 711 to suppress bending. Next, the user operates the guidewire operating member 780 in the distal direction to cause the guidewire 770 to protrude from the tip of the inner needle 12 and insert it into a blood vessel. When the pair of restricting arms 781 move distally beyond the tip of the inner needle hub 719 as the guidewire operating member 780 moves distally, the restriction on the vertical expansion of the tip of the upper housing 720 and the tip of the lower housing 721 is released.

[0162] Next, the user operates the catheter operating member 760 in the distal direction to advance the catheter 730 and the catheter hub 750. During this movement, the pair of side gripping portions 720b of the upper housing 720 come into contact with the rigid tube 754 of the catheter hub 750 and are pushed upward, causing the upper housing 720 to open relative to the lower housing 721. This allows the catheter operating member 760 to move in the distal direction, allowing the catheter 730 to be inserted satisfactorily into the blood vessel.

[0163] Then, the user pulls the inner needle hub 719 in the proximal direction relative to the catheter 730 and the catheter hub 750 to remove the inner needle 12 from the catheter 730. As a result, the catheter 730 and the catheter hub 750 are placed on the patient side.

[0164] As described above, the catheter assembly 710 according to the seventh embodiment can also provide the same effects as those of the above-mentioned embodiments. That is, the deflection suppression mechanism 790 supports the base end side of the side opening 741a (the most distal sub-opening) of the sub-lumen 741. This makes it possible to suppress deflection of the inner needle 12 and reduce damage to the catheter 730.

[0165] Furthermore, in the catheter assembly 710, since the inner needle hub 719 has the slit 722, even in a configuration in which the catheter hub 750 is provided with the sub-port 752, the sub-port 752 easily moves along the slit 722. That is, the catheter 730 can be moved smoothly relative to the inner needle 12. In particular, since the sub-port 752 protrudes laterally from the inner needle hub 719 in the catheter assembly 710, the sub-port 752 is prevented from getting in the way when the multi-structure needle 711 is inserted, and the like, making it possible to facilitate the user's work. Furthermore, since the sub-port 752 of the catheter assembly 710 has a hard tube 754 disposed at a position in contact with the inner needle hub 719, the catheter hub 750 can be moved smoothly.

[0166] Eighth embodiment 14 and 15, a catheter assembly 810 according to the eighth embodiment has a catheter hub 850 extending toward the base end side relative to a catheter operating member 860, and a sub-port 852 is provided at the extending portion of the catheter hub 850. As in the first embodiment, the catheter 830 has a main lumen 834 and a sub-lumen 841, and forms a multi-structure needle 811 by accommodating an inner needle 12 before puncture. The catheter 830 has a tip opening 834a at its tip that communicates with the main lumen 834, and also has a side opening 841a at a position spaced a predetermined distance (e.g., 17 mm or more) from the tip opening 834a that communicates with the sub-lumen 841.

[0167] Additionally, the sub-port 852 of the catheter hub 850 has a sub-hub 853 and a flexible tube 855 that connects between the main hub 851 and the sub-hub 853 .

[0168] Similarly to the seventh embodiment, the inner needle hub 819 of the catheter assembly 810 has an upper housing 820 and a lower housing 821 that are stacked vertically, and tip ends 820a, 821a are closed in the pre-puncture state. A slit 822 extending in the longitudinal direction of the inner needle hub 819 is formed between the upper housing 820 and the lower housing 821. The tip end 821a of the lower housing 821 has a right tip end 823R and a left tip end 823L, and is configured to be expandable in the left-right direction.

[0169] Tip portion 820a of upper housing 820 has a restricting portion 824 that restricts right tip portion 823R and left tip portion 823L of lower housing 821 from opening in the left-right direction in the pre-puncture state. Restricting portion 824 holds both the left and right sides of right tip portion 823R and left tip portion 823L by a pair of plate portions (not shown), and has a configuration in which the upper sides of the pair of plate portions (not shown) are connected by a bridge portion.

[0170] The catheter assembly 810 includes a right tip portion 823R and a left tip portion 823L that form a deflection suppression mechanism 890. A holding groove 825 is formed in each of the right tip portion 823R and the left tip portion 823L. A hole-shaped sliding support portion 891 that rubs against the catheter 830 when the catheter 830 advances relative to the inner needle 12 is formed by the wall portions that form the two holding grooves 825. In the initial state of the catheter assembly 810, a slight gap is formed between the outer surface of the catheter 830 and the inner surface of the sliding support portion 891. In addition, the sliding support portion 891 (deflection suppression mechanism 890) supports the base end side of the lateral opening 841a (the sub-opening located at the most distal end side) of the sub-lumen 841.

[0171] Furthermore, a guide passage 826 extending in the longitudinal direction is provided in the upper housing 820. A sub-port 852 (soft tube 855) of the catheter hub 850 is exposed from the inside to the outside of the upper housing 820 through this guide passage 826.

[0172] The catheter operating member 860 has a central base 861 detachably connected to the base end of the catheter hub 850, and a pair of finger hooks 862 extending to both left and right sides from the central base 861. The pair of finger hooks 862 are inclined upward toward the outside in the left and right direction. The underside of the finger hook 862 is provided with multiple protrusions 862a for preventing slipping.

[0173] The catheter assembly 810 also has a guidewire 870 and a guidewire operating member 880. The upper surface of the guidewire operating member 880 is provided with a plurality of ribs 881 for hooking fingers. The guidewire operating member 880 is connected to the base end of the guidewire 870 via an intermediate connector (not shown) that is disposed within the inner needle hub 819. The guidewire operating member 880 is provided so as to be displaceable in the front-rear direction relative to the upper housing 820.

[0174] When using the catheter assembly 810 configured as above, a user inserts the multi-structure needle 811 (inner needle 12, catheter 830) into a patient. At this time, the deflection suppression mechanism 890 supports the multi-structure needle 811 to suppress deflection. Next, the user operates the guidewire operating member 880 in the distal direction to protrude the guidewire 870 from the distal end of the inner needle 12, and inserts it into a blood vessel.

[0175] The user then operates the catheter operating member 860 in the distal direction to advance the catheter 830 and the catheter hub 850. During this movement, the upper housing 820 is pushed upward by the catheter operating member 860, opening it relative to the lower housing 821. As the upper housing 820 is released, the right tip portion 823R and the left tip portion 823L of the lower housing 821 can be further separated from each other in the left-right direction. This allows the catheter operating member 860 to move in the distal direction, allowing the catheter 830 to be inserted satisfactorily into the blood vessel.

[0176] Then, the user pulls the inner needle hub 819 in the proximal direction relative to the catheter 830 and the catheter hub 850 to remove the inner needle 12 from the catheter 830. As a result, the catheter 830 and the catheter hub 850 are placed on the patient side.

[0177] As described above, the catheter assembly 810 according to the eighth embodiment can also provide the same effects as those of the above-mentioned embodiments. That is, the bending suppression mechanism 890 supports the base end side of the lateral opening 841a (the most distal sub-opening) of the sub-lumen 841. This makes it possible to suppress bending of the inner needle 12 and reduce damage to the catheter 830.

[0178] Furthermore, in this catheter assembly 810, the sub-port 852 protrudes upward from the upper housing 820. This makes it easier to grasp the inner needle hub 819, improving operability by the user.

[0179] Ninth embodiment As shown in Figure 16, the catheter assembly 910 of the ninth embodiment is basically configured in the same manner as the catheter assembly 810 of the eighth embodiment, and includes an inner needle 12, an inner needle hub 919, a catheter 930, a catheter hub 950, a catheter operating member 960, a guidewire 970, a guidewire operating member 980, and a deflection suppression mechanism 990.

[0180] The catheter 930 has a main lumen 934 and a sub-lumen 941, and in a pre-puncture state, houses the inner needle 12 to form a multi-structure needle 911. The catheter 930 has a tip opening 934a at its tip that communicates with the main lumen 934, and also has a side opening 941a at a position spaced a predetermined distance (e.g., 17 mm or more) from the tip opening 934a that communicates with the sub-lumen 941.

[0181] The catheter hub 950 is disposed on the proximal side of the catheter operating member 960, and is configured to include a main hub 951 and a sub-port 952 provided at an extending portion of the main hub 951. The sub-port 952 has a sub-hub 953 and a soft tube 955 that connects the main hub 951 and the sub-hub 953.

[0182] The inner needle hub 919 of the catheter assembly 910 has an upper housing 920 and a lower housing 921 that overlap one above the other, and in the pre-puncture state, tip ends 920a, 921a are closed to each other. A slit 922 extending in the longitudinal direction of the inner needle hub 919 is formed between the upper housing 920 and the lower housing 921. In this embodiment, the slit 922 extends further toward the base end than the initial position of the catheter manipulation member 960 in the pre-puncture state.

[0183] The lower housing 921 has a right tip and a left tip that can be separated from each other to the left and right when separated from the upper housing 920, and the bending suppression mechanism 990 is constituted by this right tip and left tip. Similar to the eighth embodiment, the bending suppression mechanism 990 constitutes a sliding support portion 991 by holding grooves (not shown) of the right tip and the left tip. Further, the bending suppression mechanism 990 is located on the base end side with respect to the lateral opening 941a located at the most distal end side.

[0184] The catheter operation member 960 is supported by the upper housing 920 of the inner needle hub 919 so as to be slidable in the front-rear direction. A protrusion 961 for finger hanging is provided on the upper surface of the catheter operation member 960. The guide wire operation member 980 is displaceable with respect to the upper housing 920, and is connected to the base end portion of the guide wire 970 via an intermediate connection portion (not shown) disposed in the inner needle hub 919. A plurality of ribs 981 for finger hanging are provided on the upper surface of the guide wire operation member 980.

[0185] Here, in the catheter assembly 910, the distance Xa from the tip of the inner needle hub 919 to the protrusion 961 of the catheter operation member 960, the distance Xb from the protrusion 961 to the rib 981, and the distance Xc from the rib 981 to the base end of the inner needle hub 919 are set such that Xa < Xb < Xc. Thereby, when the user operates with one hand, the catheter assembly 910 can arrange the positions of the fingers well with respect to each operation member.

[0186] In use, the catheter assembly 910 configured as described above punctures the patient with the multi-structured needle 911 (inner needle 12, catheter 930) by the user. At this time, the bending suppression mechanism 990 supports the multi-structured needle 911 and suppresses bending. Next, the user operates the guide wire operation member 980 in the distal direction to project the guide wire 970 from the tip of the inner needle 12 and insert it into the blood vessel.

[0187] The user then operates the catheter operating member 960 in the distal direction to advance the catheter 930 and the catheter hub 950. During this movement, the upper housing 920 is pushed upward by the catheter operating member 960, opening it relative to the lower housing 921. As the upper housing 920 is released, the right and left distal ends of the lower housing 921 can be further separated from each other in the left-right direction. This allows the catheter operating member 960 to move in the distal direction, allowing the catheter 930 to be inserted satisfactorily into the blood vessel.

[0188] Then, the user pulls the inner needle hub 919 in the proximal direction relative to the catheter 930 and the catheter hub 950 to remove the inner needle 12 from the catheter 930. As a result, the catheter 930 and the catheter hub 950 are placed on the patient side.

[0189] As described above, the catheter assembly 910 according to the eighth embodiment can also provide the same effects as those of the above-mentioned embodiments. That is, the bending suppression mechanism 990 supports the base end side of the side opening 941a (the most distal sub-opening) of the sub-lumen 941. This makes it possible to suppress bending of the inner needle 12 and reduce damage to the catheter 930.

[0190] Tenth embodiment 17, a catheter assembly 1010 according to the tenth embodiment comprises an inner needle 12, a catheter 1030, a catheter hub 1050 connected to the catheter 1030, a catheter operating member 1060 for moving the catheter hub 1050 in the distal direction, an inner needle hub 1019 connected to the inner needle 12, a guidewire (not shown) inserted through the inner needle 12, a guidewire operating member 1080 connected to the guidewire, and a bending suppression mechanism 1090 for suppressing bending of the inner needle 12 at the time of puncturing. The inner needle 12 and the catheter 1030 form a multi-structure needle 1011 in the pre-puncture state.

[0191] The catheter 1030 is configured similarly to the fifth embodiment. That is, it has a main lumen 1034, a first sub-lumen 1040, and a second sub-lumen 1045. The main lumen 1034 communicates with a first distal opening 1034a and a first lateral opening 1034b at the distal end of the catheter 1030, and communicates with a proximal opening (not shown) at the proximal end of the catheter 1030. The first sub-lumen 1040 communicates with a second distal opening 1040a and a second lateral opening 1040b at the distal end of the catheter 1030, and communicates with a proximal opening (not shown) at the proximal end of the catheter 1030. The second sub-lumen 1045 communicates with a third distal opening 1045a and a third lateral opening 1045b at the distal end of the catheter 1030, and communicates with a proximal opening (not shown) at the proximal end of the catheter 1030.

[0192] The catheter hub 1050 is fixed to the base end of the catheter 1030. The catheter hub 1050 is housed in the inner needle hub 1019 in the pre-puncture state of the catheter assembly 1010. The catheter hub 1050 has a main hub 1051 connected to the catheter 1030, and a first side port 1052 and a second side port 1053 protruding laterally (horizontally perpendicular to the axis of the main hub 1051) from the main hub 1051. The first and second side ports 1052 and 1053 have a soft tube 1054 connected to the main hub 1051 via a hard tube 1051a, and a sub-hub 1055 connected to the other end of the soft tube 1054. A clamp 1056 capable of opening and closing a communication passage in the soft tube 1054 is attached to the soft tube 1054.

[0193] The catheter assembly 1010 also has a slide member 1057 that slides integrally with the catheter hub 1050 along the housing 1020 (lower extension portion 1022). The slide member 1057 has a pair of holding protrusions 1057a that are gripped by the user when removing the catheter hub 1050 from the housing 1020.

[0194] The slide member 1057 also has a storage groove 1057b that stores the tip side of the catheter hub 1050. In particular, the catheter hub 1050 according to this embodiment has a pair of wings 1058 that extend outward in the width direction from the outer circumferential surface of the tip side, and the storage groove 1057b is formed in a shape that can store the pair of wings 1058. A small hole (not shown) is provided in the wings 1058, and a convex portion (not shown) provided in the storage groove 1057b is inserted into this small hole. The storage groove 1057b also opens upward, and the catheter hub 1050 can be removed in the upward direction.

[0195] The catheter operating member 1060 is an annular member supported on the distal end of a housing 1020 (described later) of the inner needle hub 1019 so as to be slidable in the front-rear direction. The catheter operating member 1060 is provided with a finger hook 1061 that protrudes in the shape of a flange. A recess 1063 that opens toward the distal end is provided in a side wall 1062 of the catheter operating member 1060. A second side port 1053 of the catheter hub 1050 protrudes laterally through the recess 1063.

[0196] The inner needle hub 1019 has a housing 1020 that functions as a gripping portion that is gripped by the user, and an upper extension portion 1021 and a lower extension portion 1022 that extend parallel to each other in the distal direction from the distal end of the housing 1020. When the catheter assembly 1010 is in a pre-puncture state, the catheter 1030 and the catheter hub 1050 are disposed between the upper extension portion 1021 and the lower extension portion 1022.

[0197] The deflection suppression mechanism 1090 is provided at the tip of the inner needle hub 1019. Specifically, the deflection suppression mechanism 1090 includes a support member 1091 supported by the upper extension portion 1021 so as to be rotatable about an axis in the left-right direction. The support member 1091 has a sliding support portion 1092 that rubs against the catheter 1030 when the catheter 1030 advances relative to the inner needle 12. An axis portion 1093 is provided at an upper portion 1091u of the support member 1091. The axis portion 1093 is pivotally supported by the upper extension portion 1021. In addition, the tip of the guidewire operating member 1080 is located on the tip side of the upper portion 1091u of the support member 1091. Therefore, the upward rotation of the support member 1091 is restricted by the guidewire operating member 1080.

[0198] 18, the sliding support part 1092 has an upper support part 1094 capable of supporting the catheter 1030 from above, and left and right lateral support parts 1095 capable of supporting the catheter 1030 from the sides. The lateral support parts 1095 protrude downward from both the left and right ends of the upper support part 1094. Therefore, the sliding support part 1092 is formed in an inverted U shape when viewed from the longitudinal direction of the catheter assembly 1010. In the pre-puncture state, a small gap is formed between the outer surface of the catheter 1030 and the sliding support part 1092.

[0199] As shown in FIG. 17, in the initial state of the catheter assembly 1010, the sliding support portion 1092 supports the base end side of the third lateral opening 1045b located on the most distal end side.

[0200] The guidewire operating member 1080 is an operating section for performing an operation of inserting a guidewire into a blood vessel prior to an operation of inserting the catheter 1030 into a patient's blood vessel. A protrusion 1081 for hooking a finger is provided at the tip of the guidewire operating member 1080, and multiple ribs 1082 for preventing slipping are also provided. The guidewire operating member 1080 is supported on the upper surface of the upper extension portion 1021 so as to be slidable in the front-rear direction. One end of the guidewire is disposed near the tip of the inner needle 12, the other end is connected to the guidewire operating member 1080, and the middle part thereof is folded back within the housing 1020.

[0201] When using the catheter assembly 1010, a puncture operation is performed in which the catheter assembly 1010 is inserted into the skin of a patient. While holding the housing 1020 in the pre-puncture state shown in Fig. 17, the user presses the tip end of the catheter assembly 1010 against the patient, and inserts the skin toward the blood vessel to be punctured. This causes the tip ends of the inner needle 12 and the catheter 1030 to puncture the skin.

[0202] Next, when the user moves the guidewire operating member 1080 in the proximal direction, the guidewire whose middle portion has been folded back inside the housing 1020 moves in the distal direction inside the inner needle 12. As a result, the guidewire protrudes from the distal end of the inner needle 12 and is inserted into the blood vessel. As the guidewire operating member 1080 moves in the proximal direction, the distal end of the guidewire operating member 1080 moves in the proximal direction beyond the upper part of the support member 1091. As a result, the restriction by the guidewire operating member 1080 on the upward rotation of the support member 1091 is released.

[0203] Once the tip of the guidewire has been inserted to the target position within the blood vessel, the user then operates the catheter operating member 1060 in the tip direction while fixing the position of the inner needle hub 1019, to advance the catheter 1030, the catheter hub 1050, and the slide member 1057. This causes the catheter 1030 to be inserted to the target position within the blood vessel. At that time, the support member 1091 is pushed by the slide member 1057 moving in the tip direction, causing it to rotate upward. This allows the catheter 1030 to be removed from the inner needle hub 1019 in the tip direction.

[0204] Next, the user presses the pair of holding projections 1057a of the slide member 1057 to pull the housing 1020 in the proximal direction while holding the positions of the catheter 1030, the catheter hub 1050, and the slide member 1057. As a result, the catheter 1030, the catheter hub 1050, and the slide member 1057 come out completely from the inner needle hub 1019, and the inner needle 12 is removed in the proximal direction from the catheter 1030. Thereafter, the catheter hub 1050 is removed from the slide member 1057. Then, by attaching tape or the like (not shown) to a pair of wings 1058 of the catheter hub 1050, the catheter 1030 and the catheter hub 1050 are placed in the patient's blood vessel.

[0205] As described above, the catheter assembly 1010 according to the tenth embodiment can also provide the same effects as those of the above-mentioned embodiments. That is, the bending suppression mechanism 1090 supports the base end side of the third lateral opening 1045b (the sub-opening at the most base end) of the second sublumen 1045. This makes it possible to suppress bending of the inner needle 12 while also reducing damage to the catheter 1030.

[0206] In particular, the sliding support portion 1092 has an upper support portion 1094 capable of supporting the catheter 1030 from above, and a side support portion 1095 capable of supporting the catheter 1030 from the side (FIG. 18), and the third side opening 1045b is provided at either the upper portion or the side portion of the catheter 1030. With this configuration, damage to the third side opening 1045b and an increase in sliding resistance when the catheter 1030 advances can be effectively suppressed.

[0207] In addition, in the present invention, a part of each configuration given in the first to tenth embodiments and the first to eighth configuration examples can be taken out and applied to other embodiments and other configuration examples without departing from the technical spirit of the present invention.

[0208] The above embodiments can be summarized as follows.

[0209] The above embodiment discloses a catheter assembly comprising a catheter having a first lumen and a second lumen, and an inner needle inserted into the first lumen, wherein the inner needle is provided with an introduction path for checking flashback, allowing blood to flow between the catheter and the inner needle, and the distance between the tip inner surface of the first lumen connected to the tip of the catheter and the outer surface of the inner needle is narrower than the distance between a basic inner surface that constitutes the majority of the inner surface of the first lumen on the base end side of the tip inner surface and the outer surface of the inner needle.

[0210] According to this configuration, the catheter of the catheter assembly has a tip inner circumferential surface of the first lumen in close contact with or close to the outer circumferential surface of the inner needle, while a gap is formed between the basic inner circumferential surface of the first lumen and the outer circumferential surface of the inner needle. Therefore, even if the catheter is pressed by the biological tissue at the position of the tip inner circumferential surface, the catheter is reliably supported by the inner needle and bending or shrinking of the catheter is suppressed. This allows the tip of the catheter to be smoothly inserted into the body. In addition, the gap of the first lumen reduces the sliding resistance between the catheter and the inner needle and smooths the relative movement of the inner needle and the catheter, improving operability when inserting the catheter and when removing the inner needle. Furthermore, the introduction path allows blood to flow when the inner needle reaches the blood vessel, allowing the user to easily recognize that the blood vessel has been secured. In other words, the catheter assembly allows a catheter having multiple lumens to be easily inserted, and allows various treatments such as administration of multiple types of medicines or blood sampling to be smoothly performed.

[0211] In the above catheter assembly, the tip inner surface may form a tightly contacting portion that is in tight contact with the outer circumferential surface of the inner needle, thereby closing the gap that is formed between the basic inner surface and the outer circumferential surface of the inner needle.

[0212] With this configuration, the distal end of the catheter can be made thinner by forming a tight seal between the inner peripheral surface of the distal end and the inner needle, and the catheter is more reliably supported by the inner needle, thereby significantly improving the insertion performance of the catheter.

[0213] In the above-mentioned catheter assembly, the outer peripheral surface of the catheter may comprise a basic outer peripheral surface located at the location where the basic inner peripheral surface is formed, a tip outer peripheral surface located at the location where the tip inner peripheral surface is formed and having an outer diameter smaller than the basic outer peripheral surface, and a tapered outer peripheral surface that tapers from the basic outer peripheral surface toward the tip outer peripheral surface.

[0214] With this configuration, the catheter can be easily inserted into a blood vessel from the tip because the tip outer circumferential surface is thinner than the basic outer circumferential surface. Also, the tapered outer circumferential surface is inserted after the tip outer circumferential surface, and then the basic outer circumferential surface is inserted, so that the basic outer circumferential surface, which is formed thick, can be easily inserted.

[0215] In the above catheter assembly, the catheter may have a main body portion that constitutes most of the axial direction, and a flexible portion that is provided at the tip of the main body portion and is configured to be more flexible than the main body portion.

[0216] According to this configuration, when the catheter having the flexible portion is inserted into a blood vessel, the flexible portion that comes into contact with the blood vessel wall easily bends and curves along the blood vessel, improving the ease of insertion into the blood vessel and significantly reducing the occurrence of inflammation and damage to the blood vessel wall. In addition, since the inner peripheral surface of the tip of the catheter is supported by the inner needle, the occurrence of bending or contraction of the flexible portion during insertion before reaching the blood vessel can be effectively suppressed.

[0217] In the above catheter assembly, a distal opening of the second lumen may be located distally of a base end of the introduction path in the axial direction of the catheter.

[0218] With this configuration, the catheter assembly has a tip opening of the second lumen located further tip than the base end of the introduction path, making it possible to quickly confirm that blood has flowed into the second lumen.

[0219] In the above catheter assembly, an opening on the tip side of the second lumen may be located on the proximal side of the proximal end of the introduction path in the axial direction of the catheter.

[0220] According to this configuration, the catheter assembly has a distal opening of the second lumen located closer to the proximal end than the proximal end of the introduction passage, which allows the catheter to be thinner near the distal end, improving insertability. Also, blood flowing into the first lumen can be quickly confirmed.

[0221] In the above catheter assembly, an opening on the tip side of the second lumen may be configured to face a side of the catheter.

[0222] According to this configuration, the opening on the tip side of the second lumen faces the side of the catheter, thereby reducing piercing resistance.

[0223] In the above catheter assembly, an opening on the tip side of the second lumen may be provided so as to face the tip direction of the catheter.

[0224] According to this configuration, the opening on the distal end side of the second lumen faces the distal end direction of the catheter, so that the opening is prevented from being blocked by the blood vessel wall when the catheter is placed in the blood vessel. In particular, blood can be effectively sucked from the opening of the second lumen.

[0225] In the above catheter assembly, the diameter of the second lumen may be constant over the entire axial length of the catheter.

[0226] According to such a configuration, the catheter has a constant diameter of the second lumen, allowing a stable flow of the drug and enabling a guidewire or stylet to be slidably positioned.

[0227] In the above catheter assembly, a rod-shaped member that is long in the axial direction may be removably disposed in the second lumen.

[0228] According to this configuration, the catheter assembly has a rod-shaped member removably disposed in the second lumen, which improves the rigidity and straightness of the catheter, thereby allowing the catheter to be inserted more smoothly.

[0229] In the above catheter assembly, a diameter of the basic inner circumferential surface of the first lumen may be larger than a diameter of the inner circumferential surface of the second lumen.

[0230] In the above catheter assembly, a diameter of the basic inner circumferential surface of the first lumen may be smaller than a diameter of the inner circumferential surface of the second lumen.

[0231] In the above catheter assembly, the second lumen may be formed in a circumferential direction of the catheter in a direction in which a blade face of the inner needle exposed from the first lumen faces.

[0232] In the above catheter assembly, the second lumen may be formed in a circumferential direction of the catheter perpendicular to the direction in which the blade face of the inner needle exposed from the first lumen faces.

[0233] In the above catheter assembly, the second lumen may be formed in a circumferential direction of the catheter opposite to a direction in which a blade face of the inner needle exposed from the first lumen faces.

[0234] With this configuration, the catheter assembly can be appropriately designed in terms of the size and positional relationship of the first and second lumens, taking into account factors such as the insertability of the catheter, its effect on blood vessels, and the visibility of flashback.

[0235] The above catheter assembly may include a first catheter hub that fixes and holds the catheter and has a first spatial portion communicating with the first lumen, and a second catheter hub that is connected to the first catheter hub and has a second spatial portion communicating with the second lumen, and a communication passage may be provided within the first catheter hub that bypasses the first spatial portion and communicates between the second lumen and the second spatial portion.

[0236] With this configuration, the first and second catheter hubs can improve the connectivity with the connectors of the infusion or blood transfusion tubes. In particular, the communication passage allows the second space of the second catheter hub to communicate with the second lumen of the catheter, allowing for smooth flow of medicine and blood.

[0237] In the above catheter assembly, the catheter assembly may include a deflection suppression mechanism for supporting the catheter, and an opening on the tip side of the second lumen may be located on the tip side of the deflection suppression mechanism in an assembled state.

[0238] According to this configuration, in the catheter assembly, the opening on the distal end side of the second lumen is located closer to the distal end than the deflection suppression mechanism, so that the sliding resistance against the deflection suppression mechanism when the catheter is advanced can be reduced compared to when the opening is located on the proximal end side. Also, it is possible to prevent the deflection suppression mechanism from hitting the opening of the second lumen when the catheter is moved and damaging the catheter.

[0239] In the above-mentioned catheter assembly, the catheter assembly includes a deflection suppression mechanism that supports the catheter, and the catheter includes a tapered portion whose outer diameter increases from a position a predetermined distance away from the tip of the catheter toward the base end, and the tapered portion may be located closer to the tip than the deflection suppression mechanism in the assembled state.

[0240] According to this configuration, in the catheter assembly, the tapered portion is located closer to the tip than the deflection suppression mechanism, which reduces the sliding resistance of the catheter, prevents the deflection suppression mechanism from hitting the tapered portion and damaging the catheter, and eliminates steps to prevent bending of the inner needle. Furthermore, while the catheter is moving forward, the deflection suppression mechanism holds the thick-diameter portion of the catheter rather than the thin-diameter portion of the catheter, effectively preventing bending of the inner needle.

[0241] The above embodiment discloses a catheter assembly comprising an inner needle, a catheter having a main lumen through which the inner needle is detachably inserted, and one or more sub-lumens spaced apart from the main lumen, and a deflection suppression mechanism that suppresses deflection of the inner needle by supporting the inner needle via the catheter, wherein the one or more sub-lumens are connected to each of one or more sub-openings formed in the catheter, the deflection suppression mechanism has a sliding support portion that rubs against the catheter when the catheter advances relative to the inner needle, and the sliding support portion is capable of supporting the base end side of the sub-opening that is located most distal of the one or more sub-openings, or the base end side of a step portion that occurs in the catheter due to the formation of the sub-lumen.

[0242] According to this configuration, even in a catheter assembly having multiple lumens, that is, a main lumen and one or more sub-lumens, the deflection suppression mechanism supports the base end side of the most distal sub-opening, thereby suppressing deflection of the inner needle while reducing damage to the catheter. In other words, the catheter assembly can achieve both prevention of deflection of the inner needle and mobility of the catheter by appropriately arranging the formation position of the sub-opening and the support position of the deflection suppression mechanism. Therefore, a catheter having multiple lumens can be easily inserted, which makes it possible to smoothly perform various treatments, such as administration of multiple types of medicines or blood sampling.

[0243] In the above catheter assembly, the deflection suppression mechanism may be capable of supporting a portion on the proximal side of the sub-opening located most proximal side among the one or more sub-openings.

[0244] According to this configuration, the catheter assembly supports the base end side of the sub-opening located closest to the base end, thereby making it possible to more reliably prevent damage to the catheter caused by the deflection suppression mechanism.

[0245] In the above catheter assembly, the main lumen and the one or more sub-lumens may extend parallel to each other within the catheter.

[0246] According to this configuration, the catheter assembly can smoothly flow different types of medicinal liquids and administer them into a blood vessel through the main lumen and sub-lumen that extend parallel to each other.

[0247] In the above-mentioned catheter assembly, the step portion may be a tapered portion whose outer diameter gradually decreases toward the tip, the one or more sub-openings may be provided in the tapered portion, and the deflection suppression mechanism may be capable of supporting the base end side relative to the tapered portion.

[0248] According to this configuration, the catheter assembly has a deflection suppression mechanism that supports the proximal end side of the tapered portion, thereby preventing the deflection suppression mechanism from getting caught on the tapered portion, thereby further improving the mobility of the catheter.

[0249] In the above catheter assembly, the one or more sub-openings may include a side opening provided on an outer peripheral surface of the catheter, and the deflection suppression mechanism may be capable of supporting a portion on the base end side relative to the side opening.

[0250] According to this configuration, the catheter assembly has a sub-opening including a side opening, so that the medicinal fluid and blood that have flowed through the sub-lumen can be effectively discharged into the blood vessel. Moreover, because the deflection suppression mechanism is located closer to the base end than the sub-opening, damage to the side opening is also suppressed.

[0251] In the above catheter assembly, the main lumen may communicate with a main opening formed in the catheter, and the main opening may be spaced apart from the one or more sub-openings by a distance of 17 mm or more.

[0252] According to this configuration, the catheter assembly has a distance of 17 mm or more between the main opening and one or more sub-openings, so that the drug flowing out of the sub-openings mixes with the blood in the blood vessel and then mixes with the drug flowing out of the main opening. In other words, incompatible drugs can be successfully administered using a single catheter.

[0253] In the above catheter assembly, the deflection suppression mechanism may be capable of supporting a position that is 5 mm or less away from the one or more sub-openings that are closer to the distal end than the deflection suppression mechanism and are closest to the one or more sub-openings.

[0254] According to this configuration, the catheter assembly can be supported by the deflection suppression mechanism at a position 5 mm or less from the base end side of the sub-opening, so that the distance from the tip of the inner needle to the deflection suppression mechanism can be shortened and the deflection of the inner needle can be more firmly suppressed. In other words, it is preferable that the deflection suppression mechanism is provided as close to the tip side as possible from the viewpoint of suppressing the deflection of the inner needle and the tip side of the catheter. On the other hand, in a catheter having multiple lumens, it is necessary to provide each opening at a certain distance so that the medicinal liquid discharged from each opening mixes in the blood. However, if the deflection suppression mechanism is located on the tip side of the opening, there is a possibility that the deflection suppression mechanism will come into contact with the catheter near the opening and cause damage, etc. Therefore, as in this characteristic, by providing the deflection suppression mechanism near the opening at a distance that is as close as possible to the distance at which the medicinal liquid discharged from each opening mixes in the blood, it is possible to achieve both mixing in the blood and suppression of deflection.

[0255] In the above catheter assembly, the main lumen and the one or more sub-lumens may be separated by a partition that is deformable in response to pressure.

[0256] According to this configuration, the catheter assembly divides the main lumen from one or more sub-lumens by a partition wall that can deform in response to pressure, so that the main lumen can be enlarged when the inner needle is inserted before the catheter is inserted, simplifying the relative movement of the inner needle and the catheter. The partition wall deforms appropriately due to the flow pressure when a drug or blood is administered. For example, even when a relatively large amount of drug solution in the sub-lumen is flowed compared to the drug solution in the main lumen, it is possible to easily ensure the flow path cross-sectional area.

[0257] In the above catheter assembly, the deflection suppression mechanism may contactably surround the entire circumferential circumference of the catheter.

[0258] With this configuration, the catheter assembly can reliably prevent the inner needle from moving up and down and left and right (such as deviation from the bending suppression mechanism or bending of the inner needle) by the bending suppression mechanism that surrounds the entire circumferential circumference of the catheter.

[0259] The above catheter assembly may have a catheter hub that fixes and holds the catheter, and an inner needle hub that fixes and holds the inner needle, wherein the one or more sub-lumens are connected to communication passages of one or more ports provided in the catheter hub, and the ports are configured as connectors that can be connected to medical equipment.

[0260] According to this configuration, by connecting a medical device to the port, a medicinal solution or blood can be easily supplied to one or more sublumens.

[0261] In the above catheter assembly, the inner needle hub may be configured as a housing that movably accommodates the catheter hub, and the housing may have a slit that exposes the port from its inside to the outside.

[0262] According to this configuration, in the catheter assembly, since the housing has a slit, even if a port is provided in the catheter hub, the port can easily move along the slit, which allows smooth movement of the catheter relative to the inner needle.

[0263] In the above catheter assembly, the housing may be separable into upper and lower parts, the slit may form part of the boundary of the housing which is separated into upper and lower parts, and the port may protrude laterally from the housing.

[0264] With this configuration, the catheter assembly has a port protruding laterally from the housing, which prevents the port from getting in the way when inserting the inner needle and catheter, making it easier for the user to work.

[0265] In the above catheter assembly, the port may protrude upward from the inner needle hub.

[0266] According to this configuration, the catheter assembly has a port that protrudes upward from the housing, which makes it easier for the user to grip the housing and improves operability for the user.

[0267] In the above catheter assembly, the port may have a connection portion to which the medical device can be connected, and a soft tube extending between the catheter hub and the connection portion and softer than the connection portion.

[0268] According to this configuration, the catheter assembly is provided with a port including a connection portion and a soft tube, so that the connection portion can be placed in any position or posture by the user to perform puncture and catheter insertion.

[0269] In the above catheter assembly, the port may have a connection portion to which the medical device can be connected, a hard tube protruding outside the inner needle hub connected to the catheter hub, and a soft tube extending between the hard tube and the connection portion and softer than the connection portion.

[0270] With this configuration, the catheter assembly has a port formed by a connection portion, a hard tube, and a soft tube, so that the hard tube can be positioned in a position where it contacts the inner needle hub, allowing the catheter hub to be moved smoothly. [Explanation of symbols]

[0271] 10, 110, 210, 310, 510, 610, 710, 810, 910, 1010...Catheter assembly 12…Inner needle 30, 130, 230, 330, 430A~430H, 530, 630, 730, 830, 930, 1030...Catheters 34, 134, 234, 334, α, 534, 634, 734, 834, 934, 1034…Main Lumens 41, 141, 241, 341, β, β1, β2, 540, 545, 641, 741, 841, 941…Sublumen 90, 590, 690, 790, 890, 990, 1090... Deflection suppression mechanism 92, 595, 691, 791, 891, 991, 1092...Sliding support part (contact support part)

Claims

[Claim 1] Inner needle and a catheter having a lumen through which the inner needle is detachably inserted; a bending suppression mechanism that suppresses bending of the inner needle by supporting the inner needle via the catheter, The catheter includes: one or more catheter side openings; a step portion located on the base end side of the catheter side opening that is located closest to the tip end side among the one or more catheter side openings and provided so as to increase the outer diameter of the catheter; is formed, the deflection suppression mechanism has a contact support portion capable of coming into contact with the catheter when the catheter advances relative to the inner needle, A catheter assembly, wherein the contact support portion is capable of supporting the base end side of the tip end portion of the catheter side opening that is located most distal among the one or more catheter side openings, or the base end side of the step portion.

Images