JP6771406B2

JP6771406B2 - Catheter assembly

Info

Publication number: JP6771406B2
Application number: JP2017040504A
Authority: JP
Inventors: 和泉木下; 横田　崇之; 崇之横田; 誠崇村松
Original assignee: TRUMO KABUSHIKI KAISHA
Current assignee: TRUMO KABUSHIKI KAISHA
Priority date: 2017-03-03
Filing date: 2017-03-03
Publication date: 2020-10-21
Anticipated expiration: 2037-03-03
Also published as: JP2018143421A

Description

本発明は、多重構造のカテーテルを有するカテーテル組立体に関する。 The present invention relates to a catheter assembly having a multi-structured catheter.

輸液や輸血の導入部を患者に構築する際には、カテーテル組立体が使用される。例えば、特許文献１に開示されているように、カテーテル組立体は、カテーテル（外針）内に内針を挿通した多重構造針を形成している。カテーテル組立体の使用において、ユーザは、多重構造針を患者に穿刺し、カテーテルを内針に対し相対的に進出させて血管内に挿入し、さらにカテーテルから内針を離脱させることで、カテーテルを留置する。 Catheter assemblies are used to construct infusions and transfusion introductions in patients. For example, as disclosed in Patent Document 1, the catheter assembly forms a multi-structured needle in which an inner needle is inserted into a catheter (outer needle). In the use of the catheter assembly, the user punctures the patient with a multi-structured needle, inserts the catheter relative to the internal needle into the blood vessel, and then detaches the internal needle from the catheter. Detain.

特開２００８−４３４４５号公報Japanese Unexamined Patent Publication No. 2008-43445

ところで、この種のカテーテル組立体は、カテーテルを血管に挿入した際に、カテーテルの先端が血管の内壁を擦ることで、炎症や損傷等を生じさせる可能性がある。そこで、カテーテルをより柔軟に構成して炎症や損傷を抑制することが考えられるが、このようにカテーテルを柔軟にすると、多重構造針の穿刺時に、カテーテルが生体組織の抵抗力を受けて簡単に撓み血管に進入し難くなるという別の不都合が生じる。 By the way, in this type of catheter assembly, when the catheter is inserted into a blood vessel, the tip of the catheter rubs against the inner wall of the blood vessel, which may cause inflammation, damage, or the like. Therefore, it is conceivable to construct the catheter more flexibly to suppress inflammation and damage. However, if the catheter is made flexible in this way, the catheter easily receives the resistance of the living tissue when the multi-structured needle is punctured. Another inconvenience arises: it is difficult to enter the flexed blood vessel.

本発明は、上記の実情を鑑みてなされたものであって、穿刺時に適度な剛性を有する一方で、カテーテルを血管に挿入する際の血管への機械的な刺激を低減することができるカテーテル組立体を提供することを目的とする。 The present invention has been made in view of the above circumstances, and is a catheter set capable of reducing mechanical irritation to a blood vessel when inserting the catheter into a blood vessel while having appropriate rigidity at the time of puncture. The purpose is to provide a solid.

前記の目的を達成するために、本発明に係るカテーテル組立体は、内針と、前記内針の外側に配置される内側カテーテルと、前記内側カテーテルの外側に配置される外側カテーテルと、前記内側カテーテル及び外側カテーテルを固定保持するカテーテルハブと、を備え、前記内針は、前記外側カテーテルに対して相対的に後退して前記内側カテーテル及び前記外側カテーテルから抜去可能であり、前記内側カテーテルと前記外側カテーテルは、前記内針の長手方向に互いに相対移動可能であることで、前記内側カテーテルの先端が前記外側カテーテルの先端に接触する第１状態と、前記内側カテーテルの先端が前記外側カテーテルの先端から離間する第２状態と、に移行可能であり、前記カテーテルハブは、前記内側カテーテルが固定された内側カテーテルハブと、前記外側カテーテルが固定された外側カテーテルハブと、を含み、前記内側カテーテルハブは、当該内側カテーテルハブの軸方向に弾性変形可能な弾性部を、当該内側カテーテルハブの軸方向途中位置に備え、少なくとも前記弾性部よりも先端側の前記内側カテーテルハブが前記外側カテーテルハブに対して相対移動可能に構成される。
In order to achieve the above object, the catheter assembly according to the present invention includes an inner needle, an inner catheter arranged outside the inner needle, an outer catheter arranged outside the inner catheter, and the inner side. It comprises a catheter and a catheter hub that holds and holds the catheter and the outer catheter, the inner needle can be retracted relative to the outer catheter and removed from the inner and outer catheters, the inner catheter and the outer catheter. Since the outer catheter can move relative to each other in the longitudinal direction of the inner needle, the first state in which the tip of the inner catheter contacts the tip of the outer catheter and the tip of the inner catheter are the tip of the outer catheter. The catheter hub includes an inner catheter hub to which the inner catheter is fixed and an outer catheter hub to which the outer catheter is fixed, and is capable of transitioning to a second state, which is separated from the inner catheter hub. Provided an elastic portion that can be elastically deformed in the axial direction of the inner catheter hub at an axially intermediate position of the inner catheter hub, and the inner catheter hub at least on the distal end side of the elastic portion is relative to the outer catheter hub. It is configured to be relatively movable .

上記によれば、カテーテル組立体の内針、内側カテーテル及び外側カテーテルは、相互に重なった多重構造針を構成する。このため、内側カテーテルが外側カテーテルを内側から支えてカテーテル全体として適度な剛性が得られ、穿刺時に外側カテーテルが生体組織の抵抗力を受けても撓みを抑えることができる。よって、カテーテルを血管内にスムーズに刺入することが可能となる。また、内側カテーテルと外側カテーテルが内針の後退に基づき互いに長手方向に相対移動可能となることで、外側カテーテルを血管に挿入する前に、内側カテーテルの影響を抑えることができる。従って、カテーテル組立体は、血管への機械的な刺激を低減して、カテーテルをより良好に留置することができる。また、カテーテル組立体が第１状態と第２状態に移行可能であることで、内側カテーテルの先端による外側カテーテルの先端の支持と支持解除を簡単に切り替えることができる。さらに、カテーテルハブが内側カテーテルハブと外側カテーテルハブとで構成されていることで、内側カテーテル及び外側カテーテルそれぞれの操作を容易に行うことができる。そしてカテーテル組立体は、内側カテーテルハブの弾性部の伸縮による弾性力を内側カテーテルに付与することができるので、外側カテーテルに対する内側カテーテルの相対移動を容易に実施することが可能となる。
According to the above, the inner needle, the inner catheter and the outer catheter of the catheter assembly constitute a multi-structured needle that overlaps with each other. Therefore, the inner catheter supports the outer catheter from the inside to obtain appropriate rigidity of the catheter as a whole, and even if the outer catheter receives the resistance force of the living tissue at the time of puncture, the bending can be suppressed. Therefore, the catheter can be smoothly inserted into the blood vessel. In addition, since the medial catheter and the lateral catheter can move relative to each other in the longitudinal direction based on the retraction of the internal needle, the influence of the medial catheter can be suppressed before the lateral catheter is inserted into the blood vessel. Therefore, the catheter assembly can reduce mechanical irritation to the blood vessels and allow the catheter to be better placed. Further, since the catheter assembly can be transferred to the first state and the second state, it is possible to easily switch between supporting and releasing the support of the tip of the outer catheter by the tip of the inner catheter. Further, since the catheter hub is composed of the inner catheter hub and the outer catheter hub, the inner catheter and the outer catheter can be easily operated. Then, since the catheter assembly can apply an elastic force due to expansion and contraction of the elastic portion of the inner catheter hub to the inner catheter, the relative movement of the inner catheter with respect to the outer catheter can be easily performed.

この場合、前記内側カテーテルは、前記内針の後退に基づき前記外側カテーテルに対し相対移動可能となることが好ましい。 In this case, it is preferable that the inner catheter can move relative to the outer catheter based on the retraction of the inner needle.

このように、内側カテーテルが内針の後退に基づき外側カテーテルに対し相対移動可能となることで、内針が後退するまで内側カテーテルにより外側カテーテルを良好に支持することができる。 As described above, since the inner catheter can move relative to the outer catheter based on the retreat of the inner needle, the outer catheter can be satisfactorily supported by the inner catheter until the inner needle retracts.

上記構成に加えて、前記弾性部は、前記第１状態で、前記内側カテーテルの先端と前記外側カテーテルの先端とを離間させる方向に復元力を有するとよい。 In addition to the above configuration, the elastic portion may have a restoring force in the direction of separating the tip of the inner catheter and the tip of the outer catheter in the first state.

このように、弾性部が第１状態で外側カテーテルの先端と内側カテーテルの先端とを離間させる方向に復元力を有することで、内針の後退操作において他の操作を実施することなく、第２状態に円滑に移行させることができる。 As described above, since the elastic portion has a restoring force in the direction of separating the tip of the outer catheter and the tip of the inner catheter in the first state, the second operation is performed without performing another operation in the retracting operation of the inner needle. It can be smoothly transitioned to the state.

またさらに、前記内側及び外側カテーテルのうち他方と、前記内針又は該内針を固定保持する内針ハブとは、前記復元力に抗して前記第１状態を継続する係合機構を有する構成であるとよい。 Furthermore, the other of the inner and outer catheters and the inner needle or the inner needle hub that fixedly holds the inner needle have an engaging mechanism that continues the first state against the restoring force. It is good to be.

この係合機構により、カテーテル組立体は、第１状態を安定的に維持して、内側カテーテルにより外側カテーテルの内側を良好に支持することができる。 This engagement mechanism allows the catheter assembly to stably maintain the first state and to favorably support the inside of the lateral catheter with the medial catheter.

また、前記の目的を達成するために、本発明に係るカテーテル組立体は、内針と、前記内針の外側に配置される内側カテーテルと、前記内側カテーテルの外側に配置される外側カテーテルと、前記内側カテーテル及び外側カテーテルを固定保持するカテーテルハブと、を備え、前記内針は、前記外側カテーテルに対して相対的に後退して前記内側カテーテル及び前記外側カテーテルから抜去可能であり、前記内側カテーテルと前記外側カテーテルは、前記内針の長手方向に互いに相対移動可能であり、前記カテーテルハブは、前記内側カテーテルが固定された内側カテーテルハブと、前記外側カテーテルが固定され、前記内側カテーテルハブに対して移動可能な外側カテーテルハブと、で構成され、前記内針を固定保持する内針ハブは、前記外側カテーテルハブに対し相対的に後退する際に前記内側カテーテルハブを係止する後退時係止部を有し、前記内側カテーテルハブ及び前記外側カテーテルハブは、前記カテーテルに対し前記内針を後退させた際に、前記後退時係止部の係止を解除する解除機構を有することを特徴とする。
Further, in order to achieve the above object, the catheter assembly according to the present invention includes an inner needle, an inner catheter arranged outside the inner needle, and an outer catheter arranged outside the inner catheter. A catheter hub for fixing and holding the medial catheter and the lateral catheter is provided, and the internal needle is retractable relative to the lateral catheter and can be removed from the medial catheter and the lateral catheter. And the outer catheter can move relative to each other in the longitudinal direction of the inner needle, and the catheter hub is relative to the inner catheter hub to which the inner catheter is fixed and the inner catheter hub to which the outer catheter is fixed. The inner needle hub, which is composed of a movable outer catheter hub and fixedly holds the inner needle, locks the inner catheter hub when it is retracted relative to the outer catheter hub. The inner catheter hub and the outer catheter hub have a portion, and when the inner needle is retracted with respect to the catheter, the inner catheter hub and the outer catheter hub are characterized by having a releasing mechanism for releasing the locking of the retracting locking portion. To do .

このように、カテーテル組立体は、後退時係止部、解除機構を有することで、内針ハブの後退に基づき内側カテーテルハブを後退させて、解除機構において内側カテーテルハブの後退を止めることができる。これにより、内側カテーテルをある程度後退させた位置に配置して、生体組織による外側カテーテルの圧迫を内側カテーテルにより支持することができる。 As described above, since the catheter assembly has the retracting locking portion and the releasing mechanism, the inner catheter hub can be retracted based on the retracting of the inner needle hub, and the retracting of the inner catheter hub can be stopped by the releasing mechanism. .. As a result, the medial catheter can be placed at a position retracted to some extent, and the compression of the lateral catheter by the living tissue can be supported by the medial catheter.

さらに、前記解除機構は、前記内側カテーテルハブ及び前記外側カテーテルハブのうちいずれか一方に設けられた凸部と、他方に設けられた凹部とで構成されているとよい。 Further, the release mechanism may be composed of a convex portion provided on either one of the inner catheter hub and the outer catheter hub, and a concave portion provided on the other.

これにより、解除機構を簡単な構成とすることができ、内側カテーテルハブと外側カテーテルハブの製造コストを低減することができる。 As a result, the release mechanism can be made a simple structure, and the manufacturing cost of the inner catheter hub and the outer catheter hub can be reduced.

またさらに、前記内針ハブは、前記カテーテルハブに対し相対的に進出する際に前記内側カテーテルハブを係止して該内側カテーテルハブを押し出す進出時係止部を有することが好ましい。 Furthermore, it is preferable that the inner needle hub has an advancing locking portion that locks the inner catheter hub and pushes out the inner catheter hub when advancing relative to the catheter hub.

カテーテル組立体は、この進出時係止部により、外側カテーテル及び外側カテーテルハブに対し、内側カテーテル及び内側カテーテルハブを円滑に押し出すことができ、相互の組み付けを容易に行うことができる。 The catheter assembly can smoothly push out the inner catheter and the inner catheter hub with respect to the outer catheter and the outer catheter hub by the locking portion at the time of advancement, and can be easily assembled to each other.

そして、前記内側カテーテルと前記外側カテーテルとは相互に異なる硬さの材料で構成されていることが好ましい。 The inner catheter and the outer catheter are preferably made of materials having different hardness from each other.

このように、内側カテーテルと外側カテーテルとが相互に異なる材料で構成されていることで、外側カテーテルは所望の柔軟性を得ることができ、また内側カテーテルと外側カテーテルを組み合わせたカテーテルも所望の剛性とすることができる。 As described above, since the inner catheter and the outer catheter are made of different materials, the outer catheter can obtain the desired flexibility, and the catheter combining the inner catheter and the outer catheter also has the desired rigidity. Can be.

特に、前記外側カテーテルは、前記内側カテーテルよりも柔軟であることが好ましい。 In particular, the lateral catheter is preferably more flexible than the medial catheter.

これにより、柔軟な外側カテーテルを血管内に挿入していくことになるので、血管壁の炎症や損傷をより低減することができる。 As a result, a flexible outer catheter is inserted into the blood vessel, so that inflammation and damage to the blood vessel wall can be further reduced.

本発明によれば、カテーテル組立体は、穿刺時に適度な剛性を有する一方で、カテーテルを血管に挿入する際の血管への機械的な刺激を低減することができる。 According to the present invention, the catheter assembly can have moderate rigidity at the time of puncture, while reducing mechanical irritation to the blood vessel when inserting the catheter into the blood vessel.

図１Ａは、本発明の第１実施形態に係るカテーテル組立体の穿刺前状態における全体構成を示す部分側面断面図であり、図１Ｂは、図１Ａの多重構造針の先端寄りを拡大して示す側面断面図である。FIG. 1A is a partial side sectional view showing the overall configuration of the catheter assembly according to the first embodiment of the present invention in a pre-puncture state, and FIG. 1B shows an enlarged view of the tip of the multi-structure needle of FIG. 1A. It is a side sectional view. 図１のカテーテル組立体において内針が後退した穿刺後状態を示す部分側面断面図である。It is a partial side sectional view which shows the state after puncture that the inner needle retracted in the catheter assembly of FIG. 図３Ａは、多重構造針の穿刺時の一状態を示す説明図であり、図３Ｂは、多重構造針のカテーテル挿入時の一状態を示す説明図である。FIG. 3A is an explanatory diagram showing a state when the multi-structured needle is punctured, and FIG. 3B is an explanatory view showing a state when the multi-structured needle is inserted into the catheter. 図４Ａは、第２実施形態に係るカテーテル組立体の穿刺前状態における全体構成を示す部分側面断面図であり、図４Ｂは、図４Ａの多重構造針の先端寄りを拡大して示す側面断面図である。FIG. 4A is a partial side sectional view showing the overall configuration of the catheter assembly according to the second embodiment in a pre-puncture state, and FIG. 4B is an enlarged side sectional view showing the tip of the multi-structured needle of FIG. 4A. Is. 第３実施形態に係るカテーテル組立体の穿刺前状態における内針ハブを示す部分側面断面図である。It is a partial side sectional view which shows the inner needle hub in the state before puncture of the catheter assembly which concerns on 3rd Embodiment.

以下、本発明に係るカテーテル組立体について好適な実施形態を挙げ、添付の図面を参照して詳細に説明する。 Hereinafter, preferred embodiments of the catheter assembly according to the present invention will be given and will be described in detail with reference to the accompanying drawings.

〔第１実施形態〕
第１実施形態に係るカテーテル組立体１０は、患者（生体）に輸液や輸血等を行う場合に用いられ、患者の体内にカテーテルを穿刺、挿入及び留置して薬液等の導入部を構築する医療機器である。このカテーテル組立体１０は、末梢静脈に適用され、中心静脈カテーテルよりも短いカテーテルを挿入する。なお、カテーテル組立体１０は、末梢静脈カテーテルよりも長さが長い、例えば、中心静脈カテーテル、ＰＩＣＣ、ミッドラインカテーテル等を挿入するものでもよい。また、カテーテル組立体１０は、静脈用カテーテルに限らず、末梢動脈カテーテル等の動脈用カテーテルを挿入するものでもよい。 [First Embodiment]
The catheter assembly 10 according to the first embodiment is used when infusion or blood transfusion is performed on a patient (living body), and a catheter is punctured, inserted and placed in the patient's body to construct an introduction part for a drug solution or the like. It is a device. The catheter assembly 10 is applied to the peripheral vein and inserts a catheter shorter than the central venous catheter. The catheter assembly 10 may be longer than a peripheral venous catheter, for example, a central venous catheter, a PICC, a midline catheter, or the like may be inserted. Further, the catheter assembly 10 is not limited to the intravenous catheter, and may be one into which an arterial catheter such as a peripheral arterial catheter is inserted.

図１Ａに示すように、カテーテル組立体１０は、内針１２と、内針１２を固定保持する内針ハブ１４と、内針１２の外側に配置されるカテーテル１６と、カテーテル１６を固定保持するカテーテルハブ１８とを備える。特に、本実施形態に係るカテーテル１６は、２重管（多重管）に構成され、内側カテーテル２０と外側カテーテル３０とを備える。また、カテーテルハブ１８も、内側カテーテル２０を固定保持する内側カテーテルハブ４０と、外側カテーテル３０を固定保持する外側カテーテルハブ５０とで構成されている（以下、内側カテーテルハブ４０を内ハブ４０、外側カテーテルハブ５０を外ハブ５０と略称する）。 As shown in FIG. 1A, the catheter assembly 10 fixes and holds the inner needle 12, the inner needle hub 14 that holds and holds the inner needle 12, the catheter 16 that is arranged outside the inner needle 12, and the catheter 16. It includes a catheter hub 18. In particular, the catheter 16 according to the present embodiment is configured as a double tube (multiple tube), and includes an inner catheter 20 and an outer catheter 30. Further, the catheter hub 18 is also composed of an inner catheter hub 40 that holds the inner catheter 20 fixedly and an outer catheter hub 50 that holds the outer catheter 30 fixedly (hereinafter, the inner catheter hub 40 is the inner hub 40 and the outer side). The catheter hub 50 is abbreviated as the outer hub 50).

このカテーテル組立体１０は、使用前の状態（穿刺前状態）で、内側から順に、内針１２、カテーテル１６（内側及び外側カテーテル２０、３０）が重なった多重構造針１１を形成している。この穿刺前状態において、多重構造針１１は、内針１２の針先１２ａが内側カテーテル２０及び外側カテーテル３０の先端よりも突出しており、患者の体内に一体的に穿刺される。そして穿刺状態を維持しつつ、カテーテル１６を血管内に挿入し、またカテーテル１６に対し内針１２を後退及び抜去することで、カテーテル１６が血管内に留置される。後述するように、カテーテル１６は、外側カテーテル３０のみが留置される構成でもよく、外側及び内側カテーテル２０が重なったまま留置される構成でもよい。以下、このカテーテル組立体１０の各構成について詳述していく。 The catheter assembly 10 forms a multi-structured needle 11 in which an inner needle 12 and a catheter 16 (inner and outer catheters 20, 30) are overlapped in this order from the inside in a state before use (pre-puncture state). In this pre-puncture state, the multi-structured needle 11 has the needle tip 12a of the inner needle 12 protruding from the tips of the inner catheter 20 and the outer catheter 30, and is integrally punctured in the patient's body. Then, the catheter 16 is placed in the blood vessel by inserting the catheter 16 into the blood vessel and retracting and removing the inner needle 12 from the catheter 16 while maintaining the puncture state. As will be described later, the catheter 16 may be configured such that only the outer catheter 30 is indwelled, or the outer and inner catheters 20 may be indwelled while overlapping. Hereinafter, each configuration of the catheter assembly 10 will be described in detail.

内針１２は、生体の皮膚を穿刺可能な剛性を有する中空状の管体に構成され、その先端に鋭利な針先１２ａを備える。内針１２の内部には、軸方向に沿って中空部１２ｂが設けられている。なお、内針１２には、多重構造針１１の穿刺時に血液のフラッシュバックを視認可能とする構造（中空部１２ｂと外面を貫通する孔や内針１２の外周面に形成された溝等）が設けられているとよい。また内針１２は、中空部１２ｂを備えない中実状の構造でもよい。 The inner needle 12 is formed of a hollow tube body having rigidity capable of puncturing the skin of a living body, and is provided with a sharp needle tip 12a at the tip thereof. A hollow portion 12b is provided inside the inner needle 12 along the axial direction. The inner needle 12 has a structure (a hole penetrating the hollow portion 12b and the outer surface, a groove formed on the outer peripheral surface of the inner needle 12, etc.) so that the flashback of blood can be visually recognized when the multi-structure needle 11 is punctured. It is good if it is provided. Further, the inner needle 12 may have a solid structure without the hollow portion 12b.

図１Ａ及び図１Ｂに示すように、内針１２は、針先１２ａから基端方向に所定長さ離れた位置に段差部１３を有している。段差部１３は、内針１２の周方向全周に設けられ、針先１２ａに連なる先端領域αよりも径方向外側（内針１２の軸心の直交方向外側）に突出している。つまり、内針１２は、段差部１３を基点に先端領域αが薄肉に構成され、基端領域βが厚肉に構成されている。この段差部１３は、内側カテーテル２０を引掛ける係合機構６０の一方を構成する。なお、段差部１３は、内針１２の周方向の一部分に設けられるだけでもよい。 As shown in FIGS. 1A and 1B, the inner needle 12 has a stepped portion 13 at a position separated by a predetermined length from the needle tip 12a in the proximal direction. The step portion 13 is provided on the entire circumference of the inner needle 12 in the circumferential direction, and projects radially outward (outside in the orthogonal direction of the axial center of the inner needle 12) from the tip region α connected to the needle tip 12a. That is, in the inner needle 12, the tip region α is formed to be thin and the base end region β is formed to be thick with the step portion 13 as the base point. The stepped portion 13 constitutes one of the engaging mechanisms 60 for hooking the inner catheter 20. The step portion 13 may be provided only in a part of the inner needle 12 in the circumferential direction.

内針１２の構成材料としては、例えば、ステンレス鋼、アルミニウム又はアルミニウム合金、チタン又はチタン合金のような金属材料、あるいは硬質樹脂、セラミックス等があげられる。内針１２は、融着、接着、インサート成形等の適宜の固着手段により、内針ハブ１４に強固に固定される。 Examples of the constituent material of the inner needle 12 include a metal material such as stainless steel, aluminum or an aluminum alloy, titanium or a titanium alloy, a hard resin, and ceramics. The inner needle 12 is firmly fixed to the inner needle hub 14 by an appropriate fixing means such as fusion, adhesion, and insert molding.

カテーテル組立体１０の内針ハブ１４は、内針１２を固定保持して、この内針１２と一体的に移動する部材である。また内針ハブ１４は、カテーテルハブ１８の基端に離脱可能に装着され、ユーザに把持されるグリップ部分を構成している。この内針ハブ１４は、全体的に略角筒状を呈しており、ユーザが把持し易くなるように、Ｒ状の角部を有すると共に、適度なサイズ（太さ及び長さ）に設計されている。 The inner needle hub 14 of the catheter assembly 10 is a member that holds the inner needle 12 in a fixed manner and moves integrally with the inner needle 12. Further, the inner needle hub 14 is detachably attached to the base end of the catheter hub 18 to form a grip portion to be gripped by the user. The inner needle hub 14 has a substantially square tubular shape as a whole, has R-shaped corners so that the user can easily grasp it, and is designed to have an appropriate size (thickness and length). ing.

内針ハブ１４の内部及び先端部には、カテーテルハブ１８（内ハブ４０）の内部に挿入されて連結される連結部１５が設けられている。連結部１５は、カテーテルハブ１８の内周面に対応した形状（例えば、円柱状）に形成され、その外周面がカテーテルハブ１８に適度な摩擦力で嵌合される。これにより多重構造針１１の穿刺状態で、内針ハブ１４は、カテーテルハブ１８から容易に離脱可能となる。なお、内針ハブ１４とカテーテルハブ１８の連結構造は、特に限定されるものではなく、簡単な操作によって内針ハブ１４とカテーテルハブ１８とが分離可能な種々の構成（螺合構造やフランジ部との係合構造）を採用し得る。 A connecting portion 15 is provided inside and at the tip of the inner needle hub 14 so as to be inserted and connected to the inside of the catheter hub 18 (inner hub 40). The connecting portion 15 is formed in a shape (for example, a columnar shape) corresponding to the inner peripheral surface of the catheter hub 18, and the outer peripheral surface thereof is fitted to the catheter hub 18 with an appropriate frictional force. As a result, the inner needle hub 14 can be easily detached from the catheter hub 18 in the punctured state of the multi-structure needle 11. The connection structure between the inner needle hub 14 and the catheter hub 18 is not particularly limited, and various configurations (screw structure and flange portion) in which the inner needle hub 14 and the catheter hub 18 can be separated by a simple operation are not particularly limited. Engagement structure with) can be adopted.

２重菅構造のカテーテル１６の一方を構成する内側カテーテル２０は、可撓性を有し所定長さに形成された管状の部材であり、内針１２の外側に配置されて内針１２を部分的に覆っている。内側カテーテル２０の内部には、この内側カテーテル２０の軸方向に沿って延び、内針１２を挿通及び配置可能な内腔２０ａが形成されている。 The inner catheter 20 constituting one of the catheters 16 having a double tube structure is a tubular member having flexibility and formed to a predetermined length, and is arranged outside the inner needle 12 to partially form the inner needle 12. Covers the target. Inside the inner catheter 20, a lumen 20a extending along the axial direction of the inner catheter 20 into which the inner needle 12 can be inserted and arranged is formed.

内側カテーテル２０の先端側の外周面は、先端方向に向かって先細りに形成されている。また内側カテーテル２０の先端側の内周面は、内針１２の外周面に接触可能な所定形状に形成されている。具体的には、内針１２の先端領域αの外周面に接触する第１内周面２１と、第１内周面２１の基端側で第１内周面２１の直径よりも大きな直径の第２内周面２２と、第２内周面２２の基端側で第２内周面２２の直径よりも大きな直径の第３内周面２３とを有する。 The outer peripheral surface of the inner catheter 20 on the distal end side is formed so as to taper toward the distal end. Further, the inner peripheral surface on the distal end side of the inner catheter 20 is formed in a predetermined shape so as to be in contact with the outer peripheral surface of the inner needle 12. Specifically, the diameter of the first inner peripheral surface 21 that contacts the outer peripheral surface of the tip region α of the inner needle 12 and the diameter of the base end side of the first inner peripheral surface 21 that is larger than the diameter of the first inner peripheral surface 21. It has a second inner peripheral surface 22 and a third inner peripheral surface 23 having a diameter larger than the diameter of the second inner peripheral surface 22 on the proximal end side of the second inner peripheral surface 22.

第１内周面２１と第２内周面２２との間には、内側カテーテル２０の軸方向と直交する段差状の内側引掛部２４が設けられている。この内側引掛部２４は、穿刺前状態で、内針１２の段差部１３に引っ掛かる係合機構６０の他方を構成している。すなわち、係合機構６０は、内側引掛部２４と内針１２の段差部１３とに構成することで、内側カテーテル２０が内針１２に対して相対的に後退することを規制する。 A stepped inner hook portion 24 perpendicular to the axial direction of the inner catheter 20 is provided between the first inner peripheral surface 21 and the second inner peripheral surface 22. The inner hooking portion 24 constitutes the other side of the engaging mechanism 60 that is hooked on the stepped portion 13 of the inner needle 12 in the state before puncture. That is, the engaging mechanism 60 is configured as the inner hook portion 24 and the stepped portion 13 of the inner needle 12 to prevent the inner catheter 20 from retracting relative to the inner needle 12.

また、第２内周面２２と第３内周面２３との間には、基端方向に向かって径方向外側に拡がるテーパ段差２５が設けられている。第３内周面２３は、テーパ段差２５により内針１２の外周面に対して隙間２６を形成することになる。内側カテーテル２０の基端側は、この第３内周面２３が延在して空間的余白を形成しており、内針１２の摺動抵抗を低減することが可能である。 Further, between the second inner peripheral surface 22 and the third inner peripheral surface 23, a tapered step 25 extending radially outward toward the proximal end direction is provided. The third inner peripheral surface 23 forms a gap 26 with respect to the outer peripheral surface of the inner needle 12 due to the tapered step 25. On the proximal end side of the inner catheter 20, the third inner peripheral surface 23 extends to form a spatial margin, and the sliding resistance of the inner needle 12 can be reduced.

内側カテーテル２０の構成材料は、適度な剛性（コシ）及び可撓性を有するものであれば特に限定されず、適宜の樹脂材料を適用してよい。例えば、内側カテーテル２０の構成材料としては、ポリテトラフルオロエテレン（ＰＴＦＥ）、エチレン・テトラフルオロエテレン共重合体（ＥＴＦＥ）、ベルフルオロアルコキシフッ素樹脂（ＰＦＡ）等のフッ素系樹脂、ポリエチレン、ポリプロピレン等のオレフィン系樹脂又はこれらの混合物、ポリウレタン、ポリエステル、ポリアミド、ポリエーテルナイロン樹脂、前記オレフィン系樹脂とエチレンー酢酸ビニル共重合体との混合物等があげられる。 The constituent material of the inner catheter 20 is not particularly limited as long as it has appropriate rigidity (stiffness) and flexibility, and an appropriate resin material may be applied. For example, the constituent materials of the inner catheter 20 include fluororesins such as polytetrafluoroethane (PTFE), ethylene / tetrafluoroethane copolymer (ETFE), and perfluoroalkoxy alkane resin (PFA), polyethylene, and polypropylene. Such as olefin resins or mixtures thereof, polyurethanes, polyesters, polyamides, polyether nylon resins, mixtures of the olefin resins with ethylene-vinyl acetate copolymers and the like.

内側カテーテル２０の基端部は、例えば、かしめ、融着(熱融着、高周波融着等)、接着剤による接着等の適宜の接合方法によって、内ハブ４０の先端部に固定される。この内ハブ４０は、穿刺前状態で、外ハブ５０内に挿入される共に、外ハブ５０に対して離脱可能に固定されている。 The base end portion of the inner catheter 20 is fixed to the tip end portion of the inner hub 40 by an appropriate joining method such as caulking, fusion (heat fusion, high frequency fusion, etc.), adhesion with an adhesive, or the like. The inner hub 40 is inserted into the outer hub 50 and is detachably fixed to the outer hub 50 in the state before puncture.

内ハブ４０の構成材料は、特に限定されるものではないが、例えば、ポリプロピレン、ポリカーボネート、ポリアミド、ポリスルホン、ポリアリレート、メタクリレート−ブチレン−スチレン共重合体等の熱可塑性樹脂を適用するとよい。 The constituent material of the inner hub 40 is not particularly limited, but for example, a thermoplastic resin such as polypropylene, polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer may be applied.

内ハブ４０は、内側カテーテル２０よりも大径に形成された筒体であり、先端方向に向かって急角度で先細りとなる先端テーパ部４１と、先端テーパ部４１に連なり先端方向に向かって緩やかな角度で先細りとなる基端テーパ部４２とを有する。また内ハブ４０の内部には、内側カテーテル２０の内腔２０ａに連通すると共に、内針１２が挿通される内部空間４０ａが形成されている。 The inner hub 40 is a tubular body formed to have a diameter larger than that of the inner catheter 20, and has a tip tapered portion 41 that tapers at a steep angle toward the tip and a tip taper portion 41 that is connected to the tip taper portion 41 and is gentle toward the tip. It has a base end tapered portion 42 that tapers at an angle. Further, inside the inner hub 40, an internal space 40a is formed which communicates with the inner cavity 20a of the inner catheter 20 and into which the inner needle 12 is inserted.

基端テーパ部４２の基端には、内針ハブ１４の連結部１５が挿入される。基端テーパ部４２の基端内周面は、この連結部１５を嵌合する内面形状（例えばルアーテーパ）に形成されている。基端テーパ部４２の基端外周面には、径方向外側に突出する内ハブ側フランジ部４３が設けられている。 The connecting portion 15 of the inner needle hub 14 is inserted into the proximal end of the proximal end tapered portion 42. The base end inner peripheral surface of the base end taper portion 42 is formed in an inner surface shape (for example, luer taper) into which the connecting portion 15 is fitted. An inner hub-side flange portion 43 that projects outward in the radial direction is provided on the outer peripheral surface of the proximal end of the proximal end tapered portion 42.

また、カテーテル組立体１０は、内側カテーテル２０及び内ハブ４０を外側カテーテル３０及び外ハブ５０と共に留置する場合に、内部空間４０ａを介して輸液剤を流通させる。このため、内部空間４０ａには、内針１２の穿刺時に血液の逆流を防ぐ図示しない止血弁、及び輸液チューブのコネクタの挿入に伴い止血弁を貫通して輸液を可能とする図示しないプラグ等が収容されてもよい。 Further, when the inner catheter 20 and the inner hub 40 are indwelled together with the outer catheter 30 and the outer hub 50, the catheter assembly 10 allows the infusion solution to flow through the inner space 40a. For this reason, the internal space 40a includes a hemostatic valve (not shown) that prevents backflow of blood when the inner needle 12 is punctured, and a plug (not shown) that allows infusion through the hemostatic valve when the connector of the infusion tube is inserted. It may be contained.

そして、本実施形態に係る内ハブ４０の軸方向途中位置には、内ハブ４０の軸方向に伸縮自在なゴム部材４４（弾性部）が設けられている。ゴム部材４４は、前後の内ハブ４０の筒部に揃うような（一連に連なるような）外形で、内ハブ４０の周方向に沿って環状に周回している。 A rubber member 44 (elastic portion) that can expand and contract in the axial direction of the inner hub 40 is provided at an axially intermediate position of the inner hub 40 according to the present embodiment. The rubber member 44 has an outer shape that is aligned (continuously connected) with the tubular portions of the front and rear inner hubs 40, and circulates in an annular shape along the circumferential direction of the inner hub 40.

ゴム部材４４は、内ハブ４０の軸方向に弾性変形（伸縮）することにより、ゴム部材４４よりも先端側の内ハブ４０及び内側カテーテル２０と、ゴム部材４４よりも基端側の内ハブ４０との相対的な距離を変化させる。このゴム部材４４の伸縮により、内側カテーテル２０の先端は、図１Ａに示すように外側カテーテル３０の先端に接触した第１状態（穿刺前状態）と、図２に示すように穿刺前状態よりも基端方向に後退した第２状態（穿刺後状態）とに移行自在となる。 The rubber member 44 elastically deforms (expands and contracts) in the axial direction of the inner hub 40, so that the inner hub 40 and the inner catheter 20 on the distal end side of the rubber member 44 and the inner hub 40 on the proximal end side of the rubber member 44 Change the relative distance to. Due to the expansion and contraction of the rubber member 44, the tip of the inner catheter 20 is in contact with the tip of the outer catheter 30 as shown in FIG. 1A (pre-puncture state) and as shown in FIG. It is possible to freely shift to the second state (post-puncture state) retracted in the proximal direction.

図１Ａ及び図１Ｂに示すように、カテーテル組立体１０の外側カテーテル３０は、内側カテーテル２０と同様に、可撓性を有する管状の部材であり、外ハブ５０から延出している内側カテーテル２０全体を覆っている。外側カテーテル３０の内部には、この外側カテーテル３０の軸方向に沿って延び、内針１２及び内側カテーテル２０を配置可能な内腔３０ａが形成されている。 As shown in FIGS. 1A and 1B, the outer catheter 30 of the catheter assembly 10 is a flexible tubular member similar to the inner catheter 20, and the entire inner catheter 20 extending from the outer hub 50. Covering. Inside the outer catheter 30, a lumen 30a is formed which extends along the axial direction of the outer catheter 30 and on which the inner needle 12 and the inner catheter 20 can be placed.

外側カテーテル３０の先端側の外周面は、先端方向に向かって先細りに形成されている。この外側カテーテル３０は、軸方向に沿って概ね一定の肉厚で延び、内腔３０ａを構成する内周面が、内側カテーテル２０の外周面に接触している。 The outer peripheral surface of the outer catheter 30 on the distal end side is formed so as to taper toward the distal end. The outer catheter 30 extends along the axial direction with a substantially constant wall thickness, and the inner peripheral surface forming the lumen 30a is in contact with the outer peripheral surface of the inner catheter 20.

外側カテーテル３０の先端側の内周面は、先細りに形成されている内側カテーテル２０の外周面に合う（面接触する）ように形成され、さらに外側カテーテル３０の最先端は、内側カテーテル２０よりも前方にあって内針１２の外周面に接触している。このような形状により、外側カテーテル３０は、多重構造針１１の穿刺時等に、その内側が良好に支えられて径方向内側への撓み等が抑制される。また、内側カテーテル２０に対し外側カテーテル３０が相対的に基端方向に移動することも規制される。 The inner peripheral surface on the distal end side of the outer catheter 30 is formed so as to match (surface contact) the outer peripheral surface of the inner catheter 20 which is tapered, and the tip of the outer catheter 30 is more advanced than the inner catheter 20. It is in front and is in contact with the outer peripheral surface of the inner needle 12. Due to such a shape, the inner side of the outer catheter 30 is well supported when the multi-structure needle 11 is punctured, and the bending inward in the radial direction is suppressed. Further, the movement of the outer catheter 30 relative to the inner catheter 20 in the proximal direction is also restricted.

この外側カテーテル３０は、内側カテーテル２０よりも軟質（つまり異なる硬さ）に形成されている。外側カテーテル３０の軟性は、内側カテーテル２０の構成材料よりも柔軟な材料によって実現されてもよく、外側カテーテル３０を薄肉にする等の形状によって実現されてもよい。外側カテーテル３０を構成する材料は、特に限定されるものではなく、例えばポリウレタン系（極軟質ポリウレタン等）、ポリエーテル系、ポリオレフィン系等の樹脂材料を適用するとよい。 The outer catheter 30 is formed to be softer (that is, different in hardness) than the inner catheter 20. The flexibility of the outer catheter 30 may be realized by a material that is more flexible than the constituent material of the inner catheter 20, or may be realized by a shape such as thinning the outer catheter 30. The material constituting the outer catheter 30 is not particularly limited, and for example, a resin material such as polyurethane-based (ultra-soft polyurethane or the like), polyether-based, or polyolefin-based may be applied.

外側カテーテル３０の基端部は、例えば、かしめ、融着(熱融着、高周波融着等)、接着剤による接着等の適宜の接合方法によって、外ハブ５０の先端部に固定される。例えば、外側カテーテル３０の基端側の外周面は、外ハブ５０内で径方向外側に拡がり、その外周面が外ハブ５０の内周面に面状に密着固定される。 The base end portion of the outer catheter 30 is fixed to the tip end portion of the outer hub 50 by an appropriate joining method such as caulking, fusion (heat fusion, high frequency fusion, etc.), adhesion with an adhesive, or the like. For example, the outer peripheral surface of the outer catheter 30 on the proximal end side expands radially outward in the outer hub 50, and the outer peripheral surface is fixed to the inner peripheral surface of the outer hub 50 in a planar manner.

外ハブ５０は、外側カテーテル３０の内腔３０ａに連通する収容空間５０ａを有し、内ハブ４０より一回り太い筒状に形成されている。外ハブ５０は、外側カテーテル３０が固定される頭部５１と、頭部５１の基端に連なり先端方向に向かって急角度で先細りとなるテーパ連結部５２と、テーパ連結部５２の基端に連なり先端方向に向かって緩やかな角度で先細りとなる胴部５３とを含む。 The outer hub 50 has a storage space 50a that communicates with the lumen 30a of the outer catheter 30, and is formed in a tubular shape that is slightly thicker than the inner hub 40. The outer hub 50 is attached to the head 51 to which the outer catheter 30 is fixed, the tapered connecting portion 52 which is connected to the proximal end of the head 51 and tapers at a steep angle toward the distal end, and the proximal end of the tapered connecting portion 52. It includes a body portion 53 that is continuous and tapers at a gentle angle toward the tip end direction.

外ハブ５０のテーパ連結部５２は、内ハブ４０の先端テーパ部４１と同じ傾斜角に設定されており、先端テーパ部４１の外周面が面接触可能となっている。穿刺前状態で、先端テーパ部４１とテーパ連結部５２とが接触することにより、内ハブ４０が外ハブ５０よりも必要以上に先端に移動することが抑制される。 The tapered connecting portion 52 of the outer hub 50 is set at the same inclination angle as the tip tapered portion 41 of the inner hub 40, and the outer peripheral surface of the tip tapered portion 41 can be surface-contacted. The contact between the tip tapered portion 41 and the tapered connecting portion 52 in the pre-puncture state prevents the inner hub 40 from moving to the tip more than necessary than the outer hub 50.

一方、胴部５３は、内ハブ４０の基端テーパ部４２と同じ傾斜角に設定されており、基端テーパ部４２の外周面が面接触可能となっている。この胴部５３は、同一の材料により一連に連続している。また、胴部５３の基端側外周面には、径方向外側に突出する外ハブ側フランジ部５４が形成されている。 On the other hand, the body portion 53 is set at the same inclination angle as the proximal end tapered portion 42 of the inner hub 40, and the outer peripheral surface of the proximal end tapered portion 42 can be surface-contacted. The body 53 is made of the same material and is continuous in a series. Further, an outer hub side flange portion 54 projecting outward in the radial direction is formed on the outer peripheral surface on the base end side of the body portion 53.

内ハブ４０と外ハブ５０は、穿刺前状態で、相互に離脱可能に固定されることで１つのカテーテルハブ１８を構成する。例えば、外ハブ５０の基端側（胴部５３）の内径に対し、内ハブ４０のゴム部材４４よりも基端側の基端テーパ部４２の外径が若干大きく形成されていることで、外ハブ５０に対し内ハブ４０を深く挿入すると適度な摩擦力で嵌合した状態となる。なお、内ハブ４０と外ハブ５０の固定手段は、特に限定されず、例えば、基端テーパ部４２と胴部５３の螺合構造、内ハブ側フランジ部４３と外ハブ側フランジ部５４を連結し合う構造等を採用するとよい。 The inner hub 40 and the outer hub 50 are fixed to each other so as to be detachable from each other in the pre-puncture state to form one catheter hub 18. For example, the outer diameter of the base end tapered portion 42 on the base end side is slightly larger than the inner diameter of the base end side (body portion 53) of the outer hub 50 than the rubber member 44 of the inner hub 40. When the inner hub 40 is deeply inserted into the outer hub 50, the inner hub 40 is fitted with an appropriate frictional force. The means for fixing the inner hub 40 and the outer hub 50 is not particularly limited, and for example, the screw structure of the base end tapered portion 42 and the body portion 53, and the inner hub side flange portion 43 and the outer hub side flange portion 54 are connected. It is advisable to adopt a structure that allows each other to work together.

以上の構成からなるカテーテル組立体１０は、穿刺前状態において、上述したように内針１２の針先１２ａをカテーテル１６（外側カテーテル３０）の先端から露出した多重構造針１１を構成している。この状態では、内針１２、内側及び外側カテーテル２０、３０の各軸心が同軸上に配置されている。 The catheter assembly 10 having the above configuration constitutes a multi-structured needle 11 in which the needle tip 12a of the inner needle 12 is exposed from the tip of the catheter 16 (outer catheter 30) as described above in the pre-puncture state. In this state, the axes of the inner needle 12, the inner and outer catheters 20, and 30 are coaxially arranged.

また、多重構造針１１の先端部は、内側カテーテル２０の第１内周面２１が内針１２の先端領域αに面接触し、内側カテーテル２０の第２内周面２２が内針１２の基端領域βに面接触している。その一方で、内側カテーテル２０の第３内周面２３が内針１２の基端領域βに対し隙間２６を挟んで対向している。さらに、外側カテーテル３０の内周面が内側カテーテル２０の外周面に隙間なく接触して内側カテーテル２０を覆っている。 Further, at the tip of the multi-structure needle 11, the first inner peripheral surface 21 of the inner catheter 20 is in surface contact with the tip region α of the inner needle 12, and the second inner peripheral surface 22 of the inner catheter 20 is the base of the inner needle 12. It is in surface contact with the edge region β. On the other hand, the third inner peripheral surface 23 of the inner catheter 20 faces the proximal region β of the inner needle 12 with a gap 26 in between. Further, the inner peripheral surface of the outer catheter 30 is in close contact with the outer peripheral surface of the inner catheter 20 to cover the inner catheter 20.

一方、カテーテルハブ１８は、外ハブ５０に対し内ハブ４０が挿入されて固定されており、このカテーテルハブ１８の基端から内針ハブ１４の連結部１５が挿入装着される。また、上記のように内側カテーテル２０の内側引掛部２４が内針１２の段差部１３に係合した状態では、内針１２によって内側カテーテル２０の先端位置が規定され、内側カテーテル２０が内ハブ４０を先端方向に引き出すように作用する。 On the other hand, the catheter hub 18 is fixed by inserting the inner hub 40 into the outer hub 50, and the connecting portion 15 of the inner needle hub 14 is inserted and mounted from the base end of the catheter hub 18. Further, in the state where the inner hook portion 24 of the inner catheter 20 is engaged with the stepped portion 13 of the inner needle 12 as described above, the tip position of the inner catheter 20 is defined by the inner needle 12, and the inner catheter 20 is the inner hub 40. Acts to pull out toward the tip.

ここで、内ハブ４０は、上述したゴム部材４４を有しているため、内側カテーテル２０の引き出し力によってゴム部材４４を伸長させて軸方向に長くなった状態となる。なお、内ハブ４０の先端テーパ部４１は、外ハブ５０のテーパ連結部５２に接触することで、ゴム部材４４の必要以上の伸びが規制される。すなわち、穿刺前状態では、内側カテーテル２０に対して、外側カテーテル３０と相対的に基端方向に向かうゴム部材４４の弾性復元力がかかっている。この弾性復元力は、内針１２の段差部１３と内側カテーテル２０の内側引掛部２４の係合力よりも小さく、また内ハブ４０の基端部と内針ハブ１４の連結部１５の嵌合力よりも小さい。従ってカテーテル組立体１０は、図１Ａに示した状態を安定的に維持することができる。 Here, since the inner hub 40 has the rubber member 44 described above, the rubber member 44 is extended by the pulling force of the inner catheter 20 and becomes elongated in the axial direction. The tip tapered portion 41 of the inner hub 40 comes into contact with the tapered connecting portion 52 of the outer hub 50, so that the rubber member 44 is restricted from stretching more than necessary. That is, in the pre-puncture state, the elastic restoring force of the rubber member 44 toward the proximal end direction is applied to the inner catheter 20 relative to the outer catheter 30. This elastic restoring force is smaller than the engaging force between the stepped portion 13 of the inner needle 12 and the inner hooking portion 24 of the inner catheter 20, and is based on the fitting force between the base end portion of the inner hub 40 and the connecting portion 15 of the inner needle hub 14. Is also small. Therefore, the catheter assembly 10 can stably maintain the state shown in FIG. 1A.

第１実施形態に係るカテーテル組立体１０は、基本的には以上のように構成されるものであり、以下その作用効果について説明する。 The catheter assembly 10 according to the first embodiment is basically configured as described above, and its action and effect will be described below.

患者に対して輸液や輸血を行う場合、ユーザ（医師又は看護師等）は、内針ハブ１４を把持操作して、図３Ａに示すように穿刺前状態の多重構造針１１を患者の血管１００内に穿刺する。穿刺時には、針先１２ａの基端付近において内側カテーテル２０が内針１２に接触支持され、さらに外側カテーテル３０が内針１２及び内側カテーテル２０に接触支持されている。これにより、柔軟に構成された外側カテーテル３０は、皮膚や血管等の生体組織から抵抗力を受けても、撓みやしわ等を生じさせることなく、血管１００に刺入されていく。 When performing infusion or blood transfusion to a patient, a user (doctor, nurse, etc.) grasps and operates the internal needle hub 14, and as shown in FIG. 3A, the multi-structured needle 11 in the pre-puncture state is used in the patient's blood vessel 100. Puncture inside. At the time of puncture, the inner catheter 20 is contact-supported by the inner needle 12 near the base end of the needle tip 12a, and the outer catheter 30 is contact-supported by the inner needle 12 and the inner catheter 20. As a result, the flexibly configured outer catheter 30 is inserted into the blood vessel 100 without causing bending or wrinkles even if it receives resistance from living tissues such as skin and blood vessels.

また穿刺において、内針１２の針先１２ａが血管壁１０１を越えて血管１００内に進入すると、ユーザは、内針１２の挿入を止めてこの位置を維持したまま、内針１２と相対的にカテーテル１６を進出させる操作を行う。この際、カテーテルハブ１８（内ハブ４０）に固定されている内針ハブ１４を基端方向に後退させて、内ハブ４０から内針ハブ１４を離脱させる。この内針ハブ１４と一体的に内針１２も後退する。 Further, in the puncture, when the needle tip 12a of the inner needle 12 crosses the blood vessel wall 101 and enters the blood vessel 100, the user stops the insertion of the inner needle 12 and maintains this position while being relatively relative to the inner needle 12. The operation of advancing the catheter 16 is performed. At this time, the inner needle hub 14 fixed to the catheter hub 18 (inner hub 40) is retracted in the proximal direction, and the inner needle hub 14 is separated from the inner hub 40. The inner needle 12 also retracts integrally with the inner needle hub 14.

そして、カテーテル組立体１０は、内針１２の後退に基づき、内側カテーテル２０も後退を行う。すなわち、内側カテーテル２０及び内ハブ４０は、穿刺前状態で、上述したように内針１２の係合機構６０に係合して外側カテーテル３０の先端に接触する位置に配置されている。この状態ではゴム部材４４が伸長して内側カテーテル２０に対し基端方向への弾性復元力をかけているため、内針１２の段差部１３（係合機構６０）が後退すると、内側カテーテル２０も合わせて後退することになる。 Then, the catheter assembly 10 also retracts the inner catheter 20 based on the retracting of the inner needle 12. That is, the inner catheter 20 and the inner hub 40 are arranged at positions where they engage with the engaging mechanism 60 of the inner needle 12 and come into contact with the tip of the outer catheter 30 in the pre-puncture state. In this state, the rubber member 44 extends to apply an elastic restoring force to the inner catheter 20 in the proximal direction. Therefore, when the stepped portion 13 (engagement mechanism 60) of the inner needle 12 retracts, the inner catheter 20 also It will also retreat.

内側カテーテル２０の後退は、図２に示すように、ゴム部材４４の弾性変形が終わる（自然状態となる）まで継続される。ゴム部材４４が弾性復元した後は、内側カテーテル２０の後退が止まり、内針１２及び内針ハブ１４が内側カテーテル２０及び内ハブ４０と相対的に後退して内ハブ４０から抜去される。すなわち、カテーテル組立体１０は、内側カテーテル２０の先端を、外側カテーテル３０の先端からゴム部材４４の伸縮分だけ離間した位置に配置する穿刺後状態に移行する。 As shown in FIG. 2, the retreat of the inner catheter 20 is continued until the elastic deformation of the rubber member 44 ends (becomes a natural state). After the rubber member 44 is elastically restored, the retraction of the inner catheter 20 is stopped, and the inner needle 12 and the inner needle hub 14 are retracted relative to the inner catheter 20 and the inner hub 40 and are removed from the inner hub 40. That is, the catheter assembly 10 shifts to the post-puncture state in which the tip of the inner catheter 20 is arranged at a position separated from the tip of the outer catheter 30 by the expansion and contraction of the rubber member 44.

この穿刺後状態では、図３Ｂに示すように患者の体内から内側カテーテル２０が完全に抜けておらず、内側カテーテル２０は外側カテーテル３０の挿入をガイドすることが可能である。また、カテーテル組立体１０は、内側カテーテル２０の後退により、刺入箇所と反対側の血管壁１０１との間に外側カテーテル３０を充分に曲げることが可能な距離をかせぐことができる。これによりユーザは、血管１００の延在方向に外側カテーテル３０を容易に挿入していくことができる。 In this post-puncture state, as shown in FIG. 3B, the inner catheter 20 is not completely removed from the patient's body, and the inner catheter 20 can guide the insertion of the outer catheter 30. Further, the catheter assembly 10 can obtain a distance that allows the outer catheter 30 to be sufficiently bent between the insertion point and the blood vessel wall 101 on the opposite side by retracting the inner catheter 20. This allows the user to easily insert the lateral catheter 30 in the extending direction of the blood vessel 100.

また、上述したように外側カテーテル３０は、柔軟に構成されているので、外側カテーテル３０の先端が血管壁１０１に強く接触して（擦って）、血管壁１０１に炎症や損傷等を生じさせることを抑制することができる。 Further, as described above, since the outer catheter 30 is flexibly configured, the tip of the outer catheter 30 strongly contacts (rubs) the blood vessel wall 101, causing inflammation or damage to the blood vessel wall 101. Can be suppressed.

そして、外側カテーテル３０を血管１００内に挿入した後は、外側カテーテル３０及び外ハブ５０を患者に留置する。この際、少なくとも内針１２は、内側カテーテル２０からも離脱している。外側カテーテル３０の留置時には、輸液チューブのコネクタ（不図示）が外ハブ５０の基端側に装着される。これにより、輸液チューブから外ハブ５０、外側カテーテル３０を介して輸液剤が供給される。 Then, after inserting the outer catheter 30 into the blood vessel 100, the outer catheter 30 and the outer hub 50 are placed in the patient. At this time, at least the inner needle 12 is also detached from the inner catheter 20. When the outer catheter 30 is indwelled, a connector (not shown) of the infusion tube is attached to the proximal end side of the outer hub 50. As a result, the infusion agent is supplied from the infusion tube via the outer hub 50 and the outer catheter 30.

なお、留置においては、内側カテーテル２０及び内ハブ４０を一緒に留置してもよく、外側カテーテル３０及び外ハブ５０から内側カテーテル２０及び内ハブ４０を引き抜いて（離脱させて）留置してもよい。内側カテーテル２０を外側カテーテル３０と一緒に留置した場合には、外側カテーテル３０のキンク等が抑制され、また生体組織から圧迫を受けても内側カテーテル２０により外側カテーテル３０の潰れが良好に抑制される。外側カテーテル３０のみを留置した場合には、外側カテーテル３０が挿入箇所に強い応力をかけて傷を広げる等の不都合を抑制することができる。 In the indwelling, the inner catheter 20 and the inner hub 40 may be indwelled together, or the inner catheter 20 and the inner hub 40 may be pulled out (separated) from the outer catheter 30 and the outer hub 50 and indwelled. .. When the inner catheter 20 is indwelled together with the outer catheter 30, the kink of the outer catheter 30 is suppressed, and the collapse of the outer catheter 30 is satisfactorily suppressed by the inner catheter 20 even when pressure is applied from the living tissue. .. When only the outer catheter 30 is indwelled, inconveniences such as the outer catheter 30 applying strong stress to the insertion point to spread the wound can be suppressed.

以上のように、第１実施形態に係るカテーテル組立体１０は、穿刺前状態で、内側カテーテル２０が外側カテーテル３０を内側から支えてカテーテル１６全体として適度な剛性が得られる。このため、穿刺時に外側カテーテル３０が生体組織の抵抗力を受けても撓みを抑えることができ、カテーテル１６を血管１００内にスムーズに刺入することが可能となる。また、内側カテーテル２０と外側カテーテル３０が長手方向に相対移動可能であることで、外側カテーテル３０を血管１００に挿入する前に、内側カテーテル２０の影響を抑えることができる。従って、カテーテル組立体１０は、血管１００への機械的な刺激を低減して、カテーテル１６をより良好に留置することができる。 As described above, in the catheter assembly 10 according to the first embodiment, the inner catheter 20 supports the outer catheter 30 from the inside in the state before puncture, and the catheter 16 as a whole can obtain appropriate rigidity. Therefore, even if the outer catheter 30 receives the resistance force of the living tissue at the time of puncture, the bending can be suppressed, and the catheter 16 can be smoothly inserted into the blood vessel 100. Further, since the inner catheter 20 and the outer catheter 30 can move relative to each other in the longitudinal direction, the influence of the inner catheter 20 can be suppressed before the outer catheter 30 is inserted into the blood vessel 100. Therefore, the catheter assembly 10 can reduce the mechanical irritation to the blood vessel 100 and better place the catheter 16.

この場合、内側カテーテル２０が内針１２の後退に基づき外側カテーテル３０に対し相対移動可能となることで、内針１２が後退するまで内側カテーテル２０により外側カテーテル３０を良好に支持することができる。また、カテーテル組立体１０は、穿刺前状態と穿刺後状態の移行により、内側カテーテル２０の先端による外側カテーテル３０の先端の支持と支持解除を簡単に切り替えることができる。 In this case, since the inner catheter 20 can move relative to the outer catheter 30 based on the retreat of the inner needle 12, the outer catheter 30 can be satisfactorily supported by the inner catheter 20 until the inner needle 12 retreats. Further, the catheter assembly 10 can easily switch between supporting and releasing the tip of the outer catheter 30 by the tip of the inner catheter 20 by shifting between the pre-puncture state and the post-puncture state.

内側カテーテル２０は、ゴム部材４４を介して固定されることで、ゴム部材４４の弾性力が付与されて、外側カテーテル３０に対する相対移動を容易に実施することできる。ゴム部材４４は、穿刺前状態で外側カテーテル３０の先端と内側カテーテル２０の先端とを離間させる方向に復元力を有するので、他の操作を行うことなく、内針１２の後退により穿刺後状態に円滑に移行させることができる。さらに、カテーテル組立体１０は、係合機構６０を有することで、穿刺前状態を安定的に維持して、内側カテーテル２０により外側カテーテル３０を良好に支持することができる。 By fixing the inner catheter 20 via the rubber member 44, the elastic force of the rubber member 44 is applied, and the relative movement with respect to the outer catheter 30 can be easily performed. Since the rubber member 44 has a restoring force in the direction of separating the tip of the outer catheter 30 and the tip of the inner catheter 20 in the pre-puncture state, the rubber member 44 is brought into the post-puncture state by retracting the inner needle 12 without performing any other operation. The transition can be smooth. Further, since the catheter assembly 10 has the engaging mechanism 60, the pre-puncture state can be stably maintained, and the outer catheter 30 can be satisfactorily supported by the inner catheter 20.

さらにまた、内側カテーテル２０と外側カテーテル３０とが相互に異なる材料で構成されていることで、外側カテーテル３０は所望の柔軟性を得ることができる。そして、柔軟な外側カテーテル３０を血管１００内に挿入していくと、血管壁１０１の炎症や損傷をより低減することができる。また、内側カテーテル２０と外側カテーテル３０を組み合わせたカテーテル１６も所望の剛性とすることができ、生体内への刺入を良好に行うことができる。 Furthermore, the medial catheter 20 and the lateral catheter 30 are made of different materials so that the lateral catheter 30 can obtain the desired flexibility. Then, by inserting the flexible outer catheter 30 into the blood vessel 100, inflammation and damage to the blood vessel wall 101 can be further reduced. Further, the catheter 16 which is a combination of the inner catheter 20 and the outer catheter 30 can also have a desired rigidity, and can be satisfactorily inserted into the living body.

なお、本発明に係るカテーテル組立体１０は、上述の実施形態に限定されず、発明の要旨に沿って種々の改変が可能である。例えば、第１実施形態に係るカテーテル組立体１０は、内側カテーテル２０に後退力を付与する弾性部としてゴム部材４４を適用したが、この構成に限定されるものではない。他の弾性部として、例えば、バネ部材を適用することもできる。 The catheter assembly 10 according to the present invention is not limited to the above-described embodiment, and various modifications can be made according to the gist of the invention. For example, in the catheter assembly 10 according to the first embodiment, the rubber member 44 is applied as an elastic portion that applies a retreating force to the inner catheter 20, but the structure is not limited to this. As another elastic portion, for example, a spring member can be applied.

また例えば、内側カテーテル２０及び外側カテーテル３０は、穿刺前状態で外側カテーテル３０の先端よりも内側カテーテル２０の先端を突出させた構成でもよい。例えば、穿刺前状態の多重構造針１１は、内針１２の外周面から径方向外側且つ基端方向に向かって、内側カテーテル２０の先端面、外側カテーテル３０の先端面が連続したテーパ状を形成していると、患者への穿刺を良好に行うことができる。 Further, for example, the inner catheter 20 and the outer catheter 30 may have a configuration in which the tip of the inner catheter 20 protrudes from the tip of the outer catheter 30 in the state before puncture. For example, the multi-structured needle 11 in the pre-puncture state has a tapered shape in which the distal end surface of the inner catheter 20 and the distal surface of the outer catheter 30 are continuous from the outer peripheral surface of the inner needle 12 toward the radial outer side and the proximal end direction. If this is done, the patient can be punctured well.

〔第２実施形態〕
第２実施形態に係るカテーテル組立体１０Ａは、図４Ａに示すように、内針１２及び内針ハブ１４と、内側カテーテル２０及び内ハブ４０とが係合する係合機構６１が第１実施形態に係る係合機構６０と異なる。なお、以降の説明において、第１実施形態に係るカテーテル組立体１０と同一の構成又は同一の機能を有する構成には、同じ符号を付し詳細な説明を省略する。 [Second Embodiment]
As shown in FIG. 4A, the catheter assembly 10A according to the second embodiment has an engaging mechanism 61 in which the inner needle 12 and the inner needle hub 14 and the inner catheter 20 and the inner hub 40 are engaged with each other. It is different from the engaging mechanism 60 according to the above. In the following description, the same configurations as those of the catheter assembly 10 according to the first embodiment or the configurations having the same functions are designated by the same reference numerals, and detailed description thereof will be omitted.

具体的に、係合機構６１は、内針ハブ１４（連結部１５）の先端面から先端方向に突出する突出部１５ａと、内ハブ４０（先端テーパ部４１）とで構成されている。つまり、内針ハブ１４の連結部１５が内ハブ４０に挿入及び嵌合した状態で、先端テーパ部４１の内周面に対し突出部１５ａの先端部が接触及び支持することで、ゴム部材４４（弾性部）の伸長状態を維持する。図示例において、突出部１５ａは筒状に形成されているが、これに限らず棒状に形成されたものが１以上突出して構成されてもよい。また図示例において、突出部１５ａは、連結部１５に一体成形されているが、これに限らず別体に形成されたものを連結部１５に接合して構成されてもよい。 Specifically, the engaging mechanism 61 is composed of a protruding portion 15a protruding from the tip end surface of the inner needle hub 14 (connecting portion 15) toward the tip end, and an inner hub 40 (tip tapered portion 41). That is, with the connecting portion 15 of the inner needle hub 14 inserted and fitted into the inner hub 40, the tip portion of the protruding portion 15a contacts and supports the inner peripheral surface of the tip tapered portion 41, whereby the rubber member 44 Maintain the stretched state of the (elastic part). In the illustrated example, the protruding portion 15a is formed in a tubular shape, but the present invention is not limited to this, and one or more rod-shaped protruding portions may be formed. Further, in the illustrated example, the protruding portion 15a is integrally molded with the connecting portion 15, but the present invention is not limited to this, and a separately formed portion may be joined to the connecting portion 15.

従ってカテーテル組立体１０Ａ（多重構造針１１Ａ）の内針１２は、図４Ｂに示すように、針先１２ａの基端側に段差部１３を備えない構成を採用する、つまり内針１２の軸方向に沿って外径を一定に延在させた形状とすることができる。これにより内針１２の製造がより簡素となる。また、内側カテーテル２０も、内周面に内側引掛部２４を備えない構成とすることができ、製造がより簡素となる。 Therefore, as shown in FIG. 4B, the inner needle 12 of the catheter assembly 10A (multi-structure needle 11A) adopts a configuration in which the step portion 13 is not provided on the proximal end side of the needle tip 12a, that is, in the axial direction of the inner needle 12. It is possible to form a shape in which the outer diameter is uniformly extended along the above. This simplifies the manufacture of the inner needle 12. Further, the inner catheter 20 can also be configured not to have the inner hooking portion 24 on the inner peripheral surface, which simplifies the manufacture.

要するに、内側カテーテル２０の穿刺前状態の位置（外側カテーテル３０の先端と内側カテーテル２０の先端が接触する位置）を維持する係合機構６０、６１も、種々の構成を採用してよい。例えば図４Ａ中の２点鎖線に示すように、係合機構６２は、内針１２の外周面から径方向外側に突出部１５ｂを突出させて、内ハブ４０（先端テーパ部４１）の内周面に係合させる構成でもよい。 In short, various configurations may be adopted for the engaging mechanisms 60 and 61 that maintain the position of the inner catheter 20 in the pre-puncture state (the position where the tip of the outer catheter 30 and the tip of the inner catheter 20 come into contact with each other). For example, as shown by the alternate long and short dash line in FIG. 4A, the engaging mechanism 62 projects the protruding portion 15b radially outward from the outer peripheral surface of the inner needle 12, and causes the inner circumference of the inner hub 40 (tip tapered portion 41). It may be configured to engage with a surface.

〔第３実施形態〕
第３実施形態に係るカテーテル組立体１０Ｂは、図５に示すように、内針ハブ１４、内ハブ４０及び外ハブ５０を相互に連動させて内側カテーテル２０及び内ハブ４０を後退させる点で、第１及び第２実施形態に係るカテーテル組立体１０、１０Ａと異なる。つまり、カテーテル組立体１０Ｂは、内ハブ４０に弾性部を備えない構成とすることができる。なお、カテーテル組立体１０Ｂの先端側は、第２実施形態の多重構造針１１Ａと同様の構成を採用することができる（図４Ｂ参照）。 [Third Embodiment]
In the catheter assembly 10B according to the third embodiment, as shown in FIG. 5, the inner needle hub 14, the inner hub 40, and the outer hub 50 are interlocked with each other to retract the inner catheter 20 and the inner hub 40. It is different from the catheter assemblies 10 and 10A according to the first and second embodiments. That is, the catheter assembly 10B can be configured so that the inner hub 40 does not have an elastic portion. The tip end side of the catheter assembly 10B can adopt the same configuration as the multilayer structure needle 11A of the second embodiment (see FIG. 4B).

具体的には、内針ハブ７０は、カテーテル１６内に挿入される連結部７１が軸方向に沿って長く延出している。そして、この連結部７１の先端部には、内ハブ４０に係合する第１係合凸部７２と第２係合凸部７３とが設けられる。第１係合凸部７２は、連結部７１の軸方向先端側に設けられ、円柱状の連結部７１の外周面を周方向に環状に周回している。第２係合凸部７３は、第１係合凸部７２から基端方向に向かって短く間をあけた位置に設けられている。この第２係合凸部７３は、第１係合凸部７２よりも径方向外側に大きく突出している。 Specifically, in the inner needle hub 70, the connecting portion 71 inserted into the catheter 16 extends long in the axial direction. The tip of the connecting portion 71 is provided with a first engaging convex portion 72 and a second engaging convex portion 73 that engage with the inner hub 40. The first engaging convex portion 72 is provided on the axially tip side of the connecting portion 71, and orbits the outer peripheral surface of the columnar connecting portion 71 in an annular shape in the circumferential direction. The second engaging convex portion 73 is provided at a position shortly spaced from the first engaging convex portion 72 toward the proximal end. The second engaging convex portion 73 projects more radially outward than the first engaging convex portion 72.

一方、内ハブ４０は、基端テーパ部４２が軸方向に短く形成され、その最も基端に径方向内側に突出する内側引掛凸部４６と、内側引掛凸部４６の軸方向同位置で径方向外側に突出する外側引掛凸部４７とを有する。内側引掛凸部４６及び外側引掛凸部４７は、内ハブ４０の内周面及び外周面を環状に周回し、また互いに逆方向に向かって同程度の突出量で突出している。 On the other hand, in the inner hub 40, the base end tapered portion 42 is formed to be short in the axial direction, and the diameter of the inner hooking convex portion 46 protruding inward in the radial direction at the most proximal end thereof and the diameter of the inner hooking convex portion 46 at the same axial position. It has an outer hooking convex portion 47 projecting outward in the direction. The inner hooking convex portion 46 and the outer hooking convex portion 47 orbit the inner peripheral surface and the outer peripheral surface of the inner hub 40 in an annular shape, and project in opposite directions with the same amount of protrusion.

内側引掛凸部４６は、上記の内針ハブ１４の第１及び第２係合凸部７２、７３に係合するものであり、カテーテル組立体１０は、第１係合凸部７２と内側引掛凸部４６によって係合機構６３を構成している。その一方で、外側引掛凸部４７は、外ハブ５０の内周面に引っ掛かるように構成されている。 The inner hook convex portion 46 engages with the first and second engaging convex portions 72 and 73 of the inner needle hub 14, and the catheter assembly 10 has the first engaging convex portion 72 and the inner hooking convex portion 72. The convex portion 46 constitutes the engaging mechanism 63. On the other hand, the outer hooking convex portion 47 is configured to be hooked on the inner peripheral surface of the outer hub 50.

外ハブ５０は、胴部５３の内周面に第１係合凹部５６及び第２係合凹部５７を有し、また第１及び第２係合凹部５６、５７の間は、外側引掛凸部４７が摺動可能となるように浅く凹んだ通路５８となっている。第１及び第２係合凹部５６、５７には、内ハブ４０の外側引掛凸部４７が挿入及び係合される。第１係合凹部５６は、内周面から浅く窪んでいる。第２係合凹部５７は、第１係合凹部５６から基端方向に向かってある程度離れた位置に設けられ、且つ第１係合凹部５６よりも深く窪んでいる。特に、外ハブ５０は、第２係合凹部５７の基端側（胴部５３の内周面）を、第２係合凹部５７の先端側（通路５８）よりも径方向内側に突出させており、外側引掛凸部４７を確実に係止することが可能である。 The outer hub 50 has a first engaging recess 56 and a second engaging recess 57 on the inner peripheral surface of the body portion 53, and an outer hooking convex portion is provided between the first and second engaging recesses 56 and 57. The passage 58 is shallowly recessed so that the 47 can slide. The outer hooking protrusion 47 of the inner hub 40 is inserted and engaged with the first and second engaging recesses 56 and 57. The first engaging recess 56 is shallowly recessed from the inner peripheral surface. The second engaging recess 57 is provided at a position separated from the first engaging recess 56 to some extent in the direction of the proximal end, and is recessed deeper than the first engaging recess 56. In particular, the outer hub 50 projects the base end side (inner peripheral surface of the body portion 53) of the second engaging recess 57 radially inward from the tip end side (passage 58) of the second engaging recess 57. It is possible to securely lock the outer hook convex portion 47.

第３実施形態に係るカテーテル組立体１０Ｂは、基本的には以上のように構成される。このカテーテル組立体１０Ｂは、組み付けにおいて、内側カテーテル２０に内針１２を挿入した状態とし、内ハブ４０と共に内針ハブ１４を外ハブ５０の収容空間５０ａ内に挿入する。この際、内針ハブ１４の第１係合凸部７２と第２係合凸部７３との間には、内ハブ４０の内側引掛凸部４６が配置されている。内針ハブ１４の挿入時には、内針ハブ１４が先端方向に進出することで、第２係合凸部７３が内側引掛凸部４６を押し出す。これにより内ハブ４０を外ハブ５０と相対的に進出させる。つまり、第２係合凸部７３は進出時係止部として機能する。 The catheter assembly 10B according to the third embodiment is basically configured as described above. In the assembly of the catheter assembly 10B, the inner needle 12 is inserted into the inner catheter 20, and the inner needle hub 14 is inserted together with the inner hub 40 into the accommodation space 50a of the outer hub 50. At this time, the inner hooking convex portion 46 of the inner hub 40 is arranged between the first engaging convex portion 72 and the second engaging convex portion 73 of the inner needle hub 14. When the inner needle hub 14 is inserted, the inner needle hub 14 advances toward the tip end, so that the second engaging convex portion 73 pushes out the inner hooking convex portion 46. As a result, the inner hub 40 is advanced relative to the outer hub 50. That is, the second engaging convex portion 73 functions as a locking portion when advancing.

内ハブ４０の進出は、内ハブ４０の外側引掛凸部４７が外ハブ５０の第１係合凹部５６に係合されるまで継続される。この係合状態では、内ハブ４０の先端テーパ部４１が外ハブ５０のテーパ連結部５２に接触し、内ハブ４０及び外ハブ５０が相互に接触したカテーテルハブ１８を構成する。多重構造針１１も、外側カテーテル３０の先端に内側カテーテル２０の先端が接触した穿刺前状態を構築する。 The advancement of the inner hub 40 is continued until the outer hooking protrusion 47 of the inner hub 40 is engaged with the first engaging recess 56 of the outer hub 50. In this engaged state, the tip tapered portion 41 of the inner hub 40 contacts the tapered connecting portion 52 of the outer hub 50, and the inner hub 40 and the outer hub 50 form a catheter hub 18 in contact with each other. The multi-structure needle 11 also establishes a pre-puncture state in which the tip of the inner catheter 20 is in contact with the tip of the outer catheter 30.

カテーテル組立体１０ｂの使用時に、ユーザは、多重構造針１１を患者に穿刺し、その穿刺状態でカテーテルハブ１８と相対的に内針ハブ１４を後退させることで、外側カテーテル３０に対し内針１２を後退させる。この際、内針ハブ１４の第１係合凸部７２は内ハブ４０の内側引掛凸部４６を引っ掛けて、内ハブ４０を一体的に後退させる。第１係合凸部７２と内側引掛凸部４６の係合力は、外側引掛凸部４７と第１係合凹部５６の係合力よりも強くなるように設計されており、内針ハブ１４は内ハブ４０を確実に後退させることができる。 When using the catheter assembly 10b, the user punctures the patient with the multi-structured needle 11 and retracts the inner needle hub 14 relative to the catheter hub 18 in the punctured state, thereby causing the inner needle 12 with respect to the outer catheter 30. To retreat. At this time, the first engaging convex portion 72 of the inner needle hub 14 hooks the inner hooking convex portion 46 of the inner hub 40, and the inner hub 40 is integrally retracted. The engaging force between the first engaging convex portion 72 and the inner hooking convex portion 46 is designed to be stronger than the engaging force between the outer hooking convex portion 47 and the first engaging concave portion 56, and the inner needle hub 14 is inside. The hub 40 can be reliably retracted.

内針ハブ１４と内ハブ４０の後退は、外側引掛凸部４７が外ハブ５０の第２係合凹部５７に係合されるまで継続される。ここで、外側引掛凸部４７と第２係合凹部５７の係合力は、第１係合凸部７２と内側引掛凸部４６の係合力よりも強くなるように設計されている。そのため、外側引掛凸部４７が第２係合凹部５７に係合された後、内針ハブ１４をさらに後退させると、第１係合凸部７２と内側引掛凸部４６との係合が解除される。すなわち、外側引掛凸部４７と第２係合凹部５７は、第１係合凸部７２による係止を解除する解除機構を有する解除機構６５として機能する。 The retreat of the inner needle hub 14 and the inner hub 40 is continued until the outer hooking protrusion 47 is engaged with the second engaging recess 57 of the outer hub 50. Here, the engaging force between the outer hooking convex portion 47 and the second engaging concave portion 57 is designed to be stronger than the engaging force between the first engaging convex portion 72 and the inner hooking convex portion 46. Therefore, when the inner needle hub 14 is further retracted after the outer hook convex portion 47 is engaged with the second engaging concave portion 57, the engagement between the first engaging convex portion 72 and the inner hook convex portion 46 is released. Will be done. That is, the outer hook convex portion 47 and the second engaging concave portion 57 function as a releasing mechanism 65 having a releasing mechanism for releasing the lock by the first engaging convex portion 72.

この解除機構６５によって、内ハブ４０を残して内針ハブ１４が後退するようになる。その結果、カテーテル組立体１０Ｂは、外側カテーテル３０の先端から内側カテーテル２０の先端を所定距離離間させた穿刺後状態としたまま、内針１２及び内針ハブ１４を内側及び外側カテーテル２０、３０から離脱させることができる。 The release mechanism 65 causes the inner needle hub 14 to retract, leaving the inner hub 40. As a result, the catheter assembly 10B keeps the inner needle 12 and the inner needle hub 14 from the inner and outer catheters 20 and 30 while keeping the tip of the inner catheter 20 separated from the tip of the outer catheter 30 by a predetermined distance after puncture. It can be separated.

以上のように、第３実施形態に係るカテーテル組立体１０Ｂは、第１係合凸部７２及び内側引掛凸部４６による係合機構６３、外側引掛凸部４７及び第２係合凹部５７の解除機構６５を有する。従って、内針ハブ１４の後退に基づき内ハブ４０を後退させて、解除機構６５において内ハブ４０の後退を止めることができる。これにより、内側カテーテル２０をある程度後退させた位置に配置して、生体組織による外側カテーテル３０の圧迫を内側カテーテル２０により支持することができる。 As described above, in the catheter assembly 10B according to the third embodiment, the engagement mechanism 63 by the first engaging convex portion 72 and the inner hooking convex portion 46, the outer hooking convex portion 47, and the second engaging concave portion 57 are released. It has a mechanism 65. Therefore, the inner hub 40 can be retracted based on the retracting of the inner needle hub 14, and the retreating of the inner hub 40 can be stopped by the release mechanism 65. As a result, the inner catheter 20 can be arranged at a position retracted to some extent, and the compression of the outer catheter 30 by the living tissue can be supported by the inner catheter 20.

また、解除機構６５は、内ハブ４０の外側引掛凸部４７と、外ハブ５０の第２係合凹部５７とにより簡単に構成することができ、内ハブ４０と外ハブ５０の製造コストを低減することができる。さらに、カテーテル組立体１０Ｂは、内針ハブ１４の第２係合凸部７３により、外側カテーテル３０及び外ハブ５０に対し、内側カテーテル２０及び内ハブ４０を円滑に押し出すことができ、相互の組み付けを容易に行うことができる。 Further, the release mechanism 65 can be easily configured by the outer hooking protrusion 47 of the inner hub 40 and the second engaging recess 57 of the outer hub 50, reducing the manufacturing cost of the inner hub 40 and the outer hub 50. can do. Further, the catheter assembly 10B can smoothly push out the inner catheter 20 and the inner hub 40 with respect to the outer catheter 30 and the outer hub 50 by the second engaging convex portion 73 of the inner needle hub 14, and can be assembled with each other. Can be easily performed.

なお、第３実施形態に係るカテーテル組立体１０Ｂも種々の応用例や変形例をとり得る。例えば、内針ハブ１４、内ハブ４０及び外ハブ５０に設けられる凸部又は凹部は、所望の係合力が得られればよく、その配置対象について自由に設計してよい。 The catheter assembly 10B according to the third embodiment can also take various application examples and modifications. For example, the protrusions or recesses provided on the inner needle hub 14, the inner hub 40, and the outer hub 50 may be freely designed as long as a desired engaging force can be obtained.

また、外ハブ５０からの内針ハブ１４の抜去と共に内ハブ４０を抜去させる構成とする場合には、外ハブ５０は、第２係合凹部５７を備えていなくてもよい。 Further, when the inner hub 40 is removed at the same time as the inner needle hub 14 is removed from the outer hub 50, the outer hub 50 does not have to be provided with the second engaging recess 57.

さらに、第１及び第２係合凸部７２、７３、内側及び外側引掛凸部４６、４７、第１及び第２係合凹部５６、５７は、一部又は全部が非環状の突起として形成されてもよい。例えば全ての凸部及び凹部が突起に形成された場合は、内針ハブ１４、内ハブ４０、外ハブ５０の周方向位置を位置決めする機構（例えば、スプライン係合）を採用するとよい。 Further, the first and second engaging protrusions 72 and 73, the inner and outer hooking protrusions 46 and 47, and the first and second engaging recesses 56 and 57 are partially or wholly formed as non-annular protrusions. You may. For example, when all the protrusions and recesses are formed on the protrusions, a mechanism (for example, spline engagement) for positioning the circumferential positions of the inner needle hub 14, the inner hub 40, and the outer hub 50 may be adopted.

１０、１０Ａ、１０Ｂ…カテーテル組立体
１１…多重構造針１２…内針
１３…段差部１４、７０…内針ハブ
１５、７１…連結部１５ａ、１５ｂ…突出部
１６…カテーテル１８…カテーテルハブ
２０…内側カテーテル２４…内側引掛部
３０…外側カテーテル４０…内側カテーテルハブ
４４…ゴム部材４６…内側引掛凸部
４７…外側引掛凸部５０…外側カテーテルハブ
５２…テーパ連結部５６…第１係合凹部
５７…第２係合凹部６０〜６３…係合機構
６５…解除機構７２…第１係合凸部
７３…第２係合凸部 10, 10A, 10B ... Catheter assembly 11 ... Multi-structure needle 12 ... Inner needle 13 ... Step portion 14, 70 ... Inner needle hub 15, 71 ... Connecting part 15a, 15b ... Protruding portion 16 ... Catheter 18 ... Catheter hub 20 ... Inner catheter 24 ... Inner hook 30 ... Outer catheter 40 ... Inner catheter hub 44 ... Rubber member 46 ... Inner hook convex 47 ... Outer hook convex 50 ... Outer catheter hub 52 ... Tapered connection 56 ... First engaging recess 57 ... Second engaging recess 60-63 ... Engagement mechanism 65 ... Disengaging mechanism 72 ... First engaging convex portion 73 ... Second engaging convex portion

Claims

With the inner needle
An inner catheter located outside the inner needle and
An outer catheter located outside the inner catheter and
A catheter hub for fixing and holding the inner catheter and the outer catheter is provided.
The inner needle is retractable relative to the outer catheter and can be removed from the inner catheter and the outer catheter.
Since the inner catheter and the outer catheter can move relative to each other in the longitudinal direction of the inner needle, the first state in which the tip of the inner catheter contacts the tip of the outer catheter and the tip of the inner catheter are in contact with each other. It is possible to shift to a second state, which is separated from the tip of the outer catheter.
The catheter hub
With the inner catheter hub to which the inner catheter is fixed,
Includes an outer catheter hub to which the outer catheter is immobilized.
The inner catheter hub is provided with an elastic portion elastically deformable in the axial direction of the inner catheter hub at an axially intermediate position of the inner catheter hub, and the inner catheter hub at least on the distal end side of the elastic portion is the outer side. A catheter assembly characterized in that it is configured to be movable relative to a catheter hub .

In the catheter assembly according to claim 1,
A catheter assembly characterized in that the inner catheter is movable relative to the outer catheter based on the retraction of the inner needle.

In the catheter assembly according to claim 1 or 2 .
A catheter assembly characterized in that the elastic portion has a restoring force in a direction in which the tip of the inner catheter and the tip of the outer catheter are separated from each other in the first state.

In the catheter assembly according to claim 3 ,
The other of the inner catheter and the outer catheter and the inner needle or the inner needle hub that fixedly holds the inner needle have an engaging mechanism that continues the first state against the restoring force. Catheter assembly.

With the inner needle
An inner catheter located outside the inner needle and
An outer catheter located outside the inner catheter and
A catheter hub for fixing and holding the inner catheter and the outer catheter is provided.
The inner needle is retractable relative to the outer catheter and can be removed from the inner catheter and the outer catheter.
The inner catheter and the outer catheter can move relative to each other in the longitudinal direction of the inner needle.
The catheter hub
With the inner catheter hub to which the inner catheter is fixed,
The outer catheter is fixed and comprises an outer catheter hub that is movable relative to the inner catheter hub.
The inner needle hub that fixedly holds the inner needle has a retracting locking portion that locks the inner catheter hub when retracting relative to the outer catheter hub.
The catheter assembly is characterized in that the inner catheter hub and the outer catheter hub have a releasing mechanism for releasing the locking of the retracting locking portion when the inner needle is retracted with respect to the catheter.

In the catheter assembly according to claim 5 ,
The release mechanism is a catheter assembly comprising a convex portion provided on one of the inner catheter hub and the outer catheter hub and a concave portion provided on the other.

In the catheter assembly according to claim 5 or 6 .
The catheter assembly is characterized by having an advancing locking portion that locks the inner catheter hub and pushes out the inner catheter hub when advancing relative to the catheter hub.

In the catheter assembly according to any one of claims 1 to 7 .
A catheter assembly characterized in that the inner catheter and the outer catheter are made of materials having different hardness from each other.

In the catheter assembly according to claim 8 ,
The outer catheter is a catheter assembly characterized by being more flexible than the inner catheter.