JP2020089501A - Percutaneous catheter - Google Patents

Abstract

To provide a percutaneous catheter capable of suppressing or preventing positional deviation to an organism of the catheter when a dilator is extracted from the catheter including a fitting member.SOLUTION: A catheter 30 comprises: a catheter tube 31 formed in a long-sized shape, allowing blood to circulate and disposed with a lumen 30A into which a dilator 50 can be inserted; and a cap 37 attachable/detachable to/from the catheter tube in a base end part of the catheter tube. The dilator is disposed with a long-sized dilator tube 51 capable of being inserted into the lumen 30A. The cap has a wall surface 37E into which the dilator tube can be inserted while being engaged with the dilator tube. A lock connector 36 of the catheter tube includes a male screw part 36B capable of being connected to and separated from the dilator due to being displaced in a circumferential direction to a central axis in the longitudinal direction of the dilator tube.SELECTED DRAWING: Figure 8

Description

The present invention relates to percutaneous catheters.

2. Description of the Related Art Conventionally, in order to perform cardiopulmonary resuscitation, circulatory support, and respiratory support in emergency treatment, treatment by a percutaneous cardiopulmonary support (PCPS) is performed. The percutaneous cardiopulmonary support method is a method of temporarily assisting/substituting for cardiopulmonary function by using an extracorporeal circulation device. An extracorporeal circulator is also used in open heart surgery.

The extracorporeal circulation device includes an extracorporeal circulation circuit including a centrifugal pump, an artificial lung, a blood removal path, a blood supply path, and the like, and exchanges gas with respect to the blood that has been removed and supplies the blood to the blood supply path. In this regard, for example, the following Patent Document 1 describes a circulation circuit of an extracorporeal circulation device.

International publication number WO2007/123156

In such a circulation circuit, a catheter provided with a blood supply hole (outflow hole) is used to send blood after gas exchange to a desired position of a living body. The diameter of the blood supply hole of the catheter is formed smaller than the inner diameter of the blood vessel. Here, when blood flows through the inside of the catheter, if the inner diameter of the catheter is too small, pressure loss during blood flow through the catheter increases. Therefore, the inner diameter of the catheter is configured to be as large as possible so as not to be too small with respect to the blood vessel diameter.

However, if the outer diameter of the catheter is made larger, the risk of blood leakage may increase. Therefore, a mounting member such as a hemostatic plug may be provided at the proximal end of the catheter. However, depending on the connection relationship between the dilator and the catheter, the position of the catheter in the longitudinal direction in the living body lumen may shift when the dilator is removed from the catheter or the attachment member.

Therefore, an object of the present invention is to provide a percutaneous catheter capable of suppressing or preventing displacement of the catheter with respect to the living body when the dilator is removed from the catheter including the attachment member.

A percutaneous catheter according to the present invention that achieves the above-mentioned object is formed in an elongated shape, blood is flowable, and a tube provided with a lumen into which a dilator can be inserted, and the tube at the proximal end of the tube. A detachable attachment member, and the dilator is provided with a long insertion portion that can be inserted into the lumen, and the attachment member is inserted into the insertion portion of the dilator while being fitted to the insertion portion. The tube or the attachment member is provided with a connection portion that can be connected and separated from the dilator by being displaced in the circumferential direction with respect to the central axis of the insertion portion in the longitudinal direction.

According to the percutaneous catheter configured as described above, the connection portion is not displaced in the longitudinal direction but is displaced in the circumferential direction with respect to the central axis in the longitudinal direction, so that connection and disconnection with the dilator can be performed. Therefore, it is possible to suppress or prevent displacement of the catheter with respect to the living body when the dilator is removed from the catheter including the attachment member.

1 is a system diagram showing an example of an extracorporeal circulation device to which a percutaneous catheter according to an embodiment of the present invention is applied. It is a side view which shows the percutaneous catheter and dilator which concern on 1st Embodiment. It is a side surface sectional view showing the percutaneous catheter concerning a 1st embodiment. It is a side view which shows a mode that the dilator was inserted in the percutaneous catheter concerning a 1st embodiment. It is a perspective view which shows the cap (attachment member) which comprises the percutaneous catheter which concerns on 1st Embodiment. It is a perspective view which shows the state which cut|disconnected the cap which concerns on FIG. 5 along an axial direction in a substantially central part. It is a side view which shows a catheter tube and a cap which constitute a percutaneous catheter, and a dilator separately. It is a side view which shows the time of screwing the catheter tube which attached the cap with the dilator. It is an expanded sectional view showing a percutaneous catheter in which a dilator was inserted. It is a figure which shows a front-end|tip tip. It is a top view which shows the percutaneous catheter and dilator which concern on 2nd Embodiment. It is a side sectional view showing a percutaneous catheter concerning a 2nd embodiment. It is a side view which shows a mode that the dilator was inserted in the percutaneous catheter concerning a 2nd embodiment. It is a side view which decomposes|disassembles and shows the catheter tube and cap which comprise the percutaneous catheter which concerns on a modification, and a dilator. It is a side view which shows the time of attaching a dilator to the cap of the percutaneous catheter which concerns on FIG.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a diagram showing an example of an extracorporeal circulation device to which a percutaneous catheter according to an embodiment of the present invention is applied. The extracorporeal circulation device can be used, for example, for percutaneous cardiopulmonary support (PCPS), which temporarily assists or substitutes the functions of the heart and lungs until the heart function is restored when the patient's heart is weak. ..

The extracorporeal circulation device 1 can be used for a venous-arterial (Veno-Arterial, VA) procedure. The venous-arterial system (Veno-Arterial, VA) is a method in which a pump is operated to remove blood from a patient's vein (for example, a vena cava), and gas is exchanged in the blood by the artificial lung 2 to oxygenate blood. After conversion, this blood is returned to the patient's artery (eg, aorta). In this way, the extracorporeal circulation device 1 can be used as a device for assisting the heart and lungs of a patient. Hereinafter, a procedure of removing blood from a patient, performing a predetermined treatment outside the body, and then sending blood again to the body of the patient is referred to as "external circulation".

As shown in FIG. 1, the extracorporeal circulation device 1 has a circulation circuit for circulating blood. The circulation circuit includes an artificial lung 2, a centrifugal pump 3, a drive motor 4 that is a driving means for driving the centrifugal pump 3, a vein side catheter (percutaneous catheter for blood removal) 5, and a control unit. The controller 10 is included.

The venous catheter (for blood removal) catheter 5 is inserted from the femoral vein, and its tip is placed in the right atrium via the inferior vena cava. The vein side catheter 5 is connected to the centrifugal pump 3 via a blood removal tube (blood removal line) 11. The blood removal tube 11 is a conduit for sending blood.

The arterial catheter (blood supply catheter) 6 is inserted from the femoral artery.

The drive motor 4 operates the centrifugal pump 3 based on the command SG of the controller 10. The centrifugal pump 3 passes the blood removed from the blood removal tube 11 through the artificial lung 2, and then returns the blood to the patient P via the blood supply tube (blood supply line) 12.

The artificial lung 2 is arranged between the centrifugal pump 3 and the blood supply tube 12. The artificial lung 2 performs gas exchange (oxygen addition and/or carbon dioxide removal) for blood. As the oxygenator 2, for example, a membrane oxygenator can be used, and particularly preferably, a hollow fiber membrane oxygenator can be used. Oxygen gas is supplied to the artificial lung 2 from the oxygen gas supply unit 13 through the tube 14. The blood supply tube 12 is a conduit connecting the artificial lung 2 and the arterial catheter 6.

For the blood removal tube 11 and the blood supply tube 12, for example, a conduit made of a synthetic resin having high transparency and elasticity such as vinyl chloride resin or silicone rubber, which can be elastically deformed, can be used. In the blood removal tube 11, blood that is a liquid flows in the V1 direction, and in the blood supply tube 12, the blood flows in the V2 direction.

In the circulation circuit shown in FIG. 1, the detection sensor 20 is arranged in the middle of the blood removal tube 11. A fast clamp 17 is arranged in the middle of the blood supply tube 12.

When air bubbles are mixed in the circuit due to an erroneous operation of the three-way stopcock 18 or breakage of the tube during extracorporeal circulation, the detection sensor 20 detects the mixed bubbles by ultrasonic waves. When the detection sensor 20 detects that there is an air bubble in the blood sent into the blood removal tube 11, the detection sensor 20 sends a detection signal to the controller 10. The controller 10 issues an alarm warning based on this detection signal, and lowers the rotation speed of the centrifugal pump 3 or stops the centrifugal pump 3. Further, the controller 10 instructs the fast clamp 17 to immediately close the blood supply tube 12 by the fast clamp 17. This prevents the bubbles from being sent into the body of the patient P. In this way, the controller 10 controls the operation of the extracorporeal circulation device 1 to prevent air bubbles from entering the body of the patient P.

The tube 11 (12, 19) of the circulation circuit of the extracorporeal circulation device 1 is provided with a pressure sensor. The pressure sensor is, for example, of the attachment position A1 of the blood removal tube 11, the attachment position A2 of the blood supply tube 12 of the circulation circuit, or the attachment position A3 of the connection tube 19 that connects the centrifugal pump 3 and the artificial lung 2 to each other. Can be placed in at least one place. The pressure sensor measures the pressure inside each of the tubes 11, 12, and 19 when the extracorporeal circulation device 1 is performing extracorporeal circulation on the patient P. The mounting position of the pressure sensor is not limited to the mounting positions A1, A2, A3, and may be mounted at any position in the circulation circuit.

(First embodiment)
Next, the catheter 30 corresponding to the percutaneous catheter according to this embodiment will be described. 2 to 10 are views for explaining the catheter 30 according to the first embodiment. The catheter 30 according to the present embodiment is used as the vein side catheter (blood removal catheter) 5 in FIG.

As shown in FIG. 2, the catheter 30 according to the present embodiment has a catheter tube 31 (corresponding to a “tube”) provided with a side hole 63, and a distal tip provided at the tip of the catheter tube 31 and provided with through holes 46, 47. 41. The catheter 30 includes a clamp tube 34 arranged on the proximal end side of the catheter tube 31, a catheter connector 35 connecting the catheter tube 31 and the clamp tube 34, a lock connector 36, and a cap 37 (in the “mounting member”). Equivalent), and.

In the present specification, the side to be inserted into the living body is referred to as “tip” or “tip side”, and the hand side operated by the operator is referred to as “base end” or “base end side”. The tip part means a certain range including the tip (the most distal end) and its periphery, and the base end part means a certain range including the base end (the most proximal end) and its periphery.

The catheter 30 has a lumen 30A penetrating from the distal end to the proximal end as shown in FIG. The through holes 46 and 47 of the distal tip 41 and the side holes 63 of the catheter tube 31 are arranged for different blood removal targets in the living body so that blood removal can be performed efficiently.

As shown in FIG. 4, the dilator 50 is used when inserting the catheter 30 into the living body. The dilator 50 is inserted into the lumen 30A of the catheter 30, and the catheter 30 and the dilator 50 are inserted into the living body in a state where they are previously integrated. Blood is allowed to flow in the lumen 30A. The method of using the catheter 30 will be described later.

The catheter tube 31 is configured to be long and extendable. The catheter tube 31 includes a first tube 32 and a second tube 33 arranged on the proximal end side of the first tube 32 as shown in FIG. 2. The first tube 32 is configured to have higher elasticity than the second tube 33.

The first tube 32 has a larger outer diameter and inner diameter than the second tube 33. The first tube 32 and the second tube 33 are integrally formed and have a substantially constant wall thickness.

The lengths of the first tube 32 and the second tube 33 are configured to be the lengths necessary for arranging the through holes 46, 47 and the side hole 63 of the distal tip 41 in a desired blood removal target. The length of the first tube 32 can be, for example, 20 to 40 cm, and the length of the second tube 33 can be, for example, 20 to 30 cm.

The side hole 63 is a hole that penetrates the side surface of the second tube 33 and is open so as to communicate with the lumen 30A of the catheter 30. The side hole 63 functions as a blood removal hole. It is preferable to provide a plurality of the side holes 63 because blood can be removed from the other side holes even if any of the side holes 63 is adsorbed and blocked by the blood vessel wall, and stable extracorporeal circulation can be performed.

In the present embodiment, blood removal targets are the right atrium and the inferior vena cava. The catheter 30 is inserted and left in the living body so that the through holes 46 and 47 of the tip 41 are arranged in the right atrium.

The first tube 32 is arranged in the inferior vena cava, which is a relatively thick blood vessel, and the second tube 33 is a femoral vein, which is a relatively thin blood vessel, with the through holes 46, 47 and the side hole 63 being arranged for blood removal. Is located in.

Further, when the dilator 50 is inserted into the lumen 30A of the catheter 30, the first tube 32 having high elasticity expands in the axial direction and the outer diameter and inner diameter of the first tube 32 become smaller as shown in FIG. At this time, the outer diameter and inner diameter of the first tube 32 are substantially the same as the outer diameter and inner diameter of the second tube 33. Since the catheter 30 is inserted into the living body in a state where the first tube 32 is extended in the axial direction and the outer diameter is reduced, the catheter 30 can be inserted minimally invasively.

When the dilator 50 is removed from the lumen 30A of the catheter 30 after the catheter 30 is left in the living body, the first tube 32 contracts in the axial direction and the outer diameter and inner diameter of the first tube 32 are increased as shown in FIG. Become. Here, since the first tube 32 is arranged in the inferior vena cava, which is a relatively thick blood vessel, the outer diameter of the first tube 32 can be increased.

Here, the pressure loss when blood or the like flows through the first tube 32 can be reduced by increasing the inner diameter of the first tube 32. When the pressure loss is reduced, the flow rate of blood flowing through the circulation circuit increases. Therefore, in order to obtain a sufficient blood circulation amount, it is necessary to make the inner diameter of the first tube 32 sufficiently large.

On the other hand, when the wall thickness is substantially constant, increasing the inner diameters of the first tube 32 and the second tube 33 also increases the outer diameters, which increases the burden on the patient when inserting the catheter 30 into the living body and reduces the Interfere with invasive procedures.

From the above viewpoints, the inner diameter of the first tube 32 may be, for example, 9 to 11 mm, and the inner diameter of the second tube 33 may be, for example, 4 to 8 mm. Moreover, the wall thickness of the 1st tube 32 and the 2nd tube 33 can be 0.3-0.5 mm, for example.

Further, as shown in FIGS. 2 and 3, the distal end portion and the proximal end portion of the first tube 32 are tapered portions that gradually become thinner from the center in the longitudinal direction of the first tube 32 toward the distal end portion and the proximal end portion. Is preferably formed. Thereby, the inner diameters of the distal end and the proximal end of the first tube 32 can easily be continuously connected to the inner diameter of the distal end tip 41 disposed on the distal end side and the inner diameter of the second tube 33 disposed on the proximal end side. it can.

Next, a specific configuration of the catheter tube 31 will be described.

As shown in FIG. 9, the catheter tube 31 includes a tubular reinforcing body 320 braided in a mesh shape so as to intersect the wires W, and a first resin layer 331 and a second resin layer provided so as to cover the reinforcing body 320. And a layer 332.

The first tube 32 is configured by the tip end portion 320a of the reinforcing body 320 and the first resin layer 331, and the second tube 33 is configured by the base end portion 320b of the reinforcing body 320 and the second resin layer 332.

By braiding the plurality of wires W, innumerable gaps or openings are formed in the reinforcing body 320. The size relationship between the plurality of gaps or openings is not particularly limited.

The second resin layer 332 is formed so as to cover the inner peripheral surface of the opening of the reinforcing body 320. This can prevent the wire from being exposed from the inner peripheral surface of the side hole 63. The maximum length of the opening can be set to a few mm.

The wire W forming the reinforcing body 320 is made of a shape memory material such as a known shape memory metal or shape memory resin. As the shape memory metal, for example, titanium-based (Ti-Ti, Ti-Pd, Ti-Nb-Sn, etc.) or copper-based alloy can be used. As the shape memory resin, for example, acrylic resin, transisoprene polymer, polynorbornene, styrene-butadiene copolymer, polyurethane can be used.

The cross-sectional shape of the wire W forming the reinforcing body 320 is rectangular in this embodiment. However, the shape is not limited to this, and may be a square, a circle, an ellipse, etc. other than the above. When the cross-sectional shape is circular, the wire diameter of the wire W can be, for example, 0.1 mm to 0.2 mm.

The first resin layer 331 forming the first tube 32 is made of a material softer than the second resin layer 332 forming the second tube 33. With this configuration, the first tube 32 can be made softer than the second tube 33, and the elasticity can be enhanced.

As a material forming the first resin layer 331, a known resin that is relatively soft can be used. For example, urethane, polyurethane, silicon, or vinyl chloride having a low hardness can be used. As the material forming the second resin layer 332, for example, urethane, polyurethane, silicon, or vinyl chloride having high hardness can be used.

When urethane or polyurethane is used, a hydrophilic coating may be applied to the surface. This increases the lubricity of the surface of the catheter tube 31, facilitates insertion into a living body, improves operability, and prevents damage to the blood vessel wall. In addition, blood and proteins are less likely to adhere, and it can be expected that thrombus formation will be prevented.

The tip 41 is fixed to the tip of the first tube 32. As shown in FIG. 9, the tip 41 has a tapered shape whose diameter is gradually reduced toward the tip side. As shown in FIG. 10, the distal tip 41 has a base portion 49 inserted into the distal end of the first tube 32, a plurality of through holes 46 provided in the side surface, and a through hole 47 provided at the distal end of the distal tip 41, Have. The through holes 46 and 47 function as blood removal holes. The through hole 47 of the tip 41 is configured to communicate with the lumen 30A of the catheter 30. The tip 41 can be formed of, for example, hard plastic.

Further, by fixing the hard tip 41 to the tip of the first tube 32, it is possible to effectively prevent the first tube 32 from collapsing during blood removal.

As shown in FIG. 9, a flat receiving surface 48 is formed inside the distal tip 41 so as to come into contact with the flat surface 50a of the dilator 50 used before inserting the catheter 30 into the living body. The flat surface 50a of the dilator 50 contacts the receiving surface 48, whereby the catheter tube 31 can be elongated in the longitudinal direction.

The clamp tube 34 is provided on the proximal end side of the second tube 33. A lumen through which the dilator 50 can be inserted is provided inside the clamp tube 34. The clamp tube 34 can be formed using the same material as the catheter tube 31.

The catheter connector 35 connects the second tube 33 and the clamp tube 34. A lumen through which the dilator 50 can be inserted is provided inside the catheter connector 35.

The lock connector 36 is connected to the proximal end side of the clamp tube 34. A lumen through which the dilator 50 can be inserted is provided inside the lock connector 36. The lock connector 36 is provided with male screw portions 36A and 36B as shown in FIGS. The male screw portion 36A corresponds to the first engaging portion in this specification, and the male screw portion 36B corresponds to the second engaging portion and the connecting portion.

The male screw portion 36A is provided on the proximal end side of the catheter tube 31 with respect to the male screw portion 36B. The male screw portion 36A is configured to be engageable with the female screw portion 37D of the cap 37 by screwing. The male screw portion 36A has a smaller radial dimension than the male screw portion 36B.

The male screw portion 36B is arranged at the proximal end portion of the catheter tube 31 on the distal side of the male screw portion 36A. The male screw portion 36B is configured to be engageable with the female screw portion 53A of the dilator 50 by screwing. As a result, the catheter tube 31 can be connected and separated from the dilator 50 by being displaced in the circumferential direction with respect to the central axis of the dilator tube 51 of the dilator 50 in the longitudinal direction. In the present embodiment, the male screw portion 36B is formed in a spiral shape having a rotation axis in the longitudinal direction, and the circumferential direction is the spiral direction of the male screw portion 36B with respect to the central axis in the longitudinal direction. There is. When the female screw portion 53A of the dilator 50 is screwed into the male screw portion 36B, the dilator 50 houses the cap 37 in the internal space 53B of the screw ring 53.

The cap 37 is provided to prevent blood leakage from the proximal end portion of the catheter 30. The cap 37 is configured to be attachable to and detachable from the catheter tube 31 at the proximal end portion of the catheter tube 31. As shown in FIGS. 5 and 6, the cap 37 includes a first hollow portion 37A, a second hollow portion 37B, a third hollow portion 37C, and a female screw portion 37D. The female screw portion 37D corresponds to the first engaged portion in this specification.

37 A of 1st hollow parts are equipped with the part which extended the substantially circular cross section similarly to the catheter tube 31 in the direction orthogonal to a cross section. On the inner surface of the first hollow portion 37A, a female screw portion 37D that can be engaged with the male screw portion 36A of the lock connector 36 by screwing is provided.

The second hollow portion 37B is configured integrally with the first hollow portion 37A and is configured to be located inward of the first hollow portion 37A. The second hollow portion 37B is provided with a wall surface 37E into which the dilator tube 51 of the dilator 50 can be inserted.

The third hollow portion 37C is configured so as to be located adjacent to the first hollow portion 37A and the second hollow portion 37B in the axial direction. Similar to the second hollow portion 37B, the third hollow portion 37C is provided with a wall surface 37E into which the dilator tube 51 of the dilator 50 can be inserted. The wall surfaces 37E of the second hollow portion 37B and the third hollow portion 37C are dimensioned such that they can be inserted while the dilator tube 51 of the dilator 50 is being fitted. The wall surface 37E corresponds to a fitting portion in this specification. The material of the cap 37 is not particularly limited, but can be made of a plastic material such as hard plastic.

(Dilator)
As shown in FIG. 2, the dilator 50 includes a dilator tube 51 extending in the axial direction, a dilator hub 52 to which the base end of the dilator tube 51 is fixed, and a screw ring 53 provided at the tip of the dilator hub 52. ,have. In this specification, the dilator tube 51 corresponds to the insertion portion, and the screw ring 53 corresponds to the connection portion.

The dilator tube 51 is an elongated body that extends in the axial direction and that can be inserted into the lumen 30A of the catheter 30 and that has relatively high rigidity. The overall length of the dilator tube 51 along the axial direction is configured to be longer than the overall length of the catheter 30 along the axial direction. The dilator tube 51 includes a guide wire lumen 54 into which a guide wire (not shown) can be inserted (see FIG. 2). The dilator tube 51 is guided by the guide wire and inserted into the living body together with the catheter 30. The dilator tube 51 is removed from the catheter 30 by leaving the catheter 30 in the living body and then withdrawing the dilator hub 52 to the proximal end side.

The tip of the dilator tube 51 is provided with a flat surface 50a that abuts the receiving surface 48 of the tip 41 as shown in FIG. The dilator tube 51 has a relatively high rigidity and is provided with a stiffness that allows the pushing force to the tip end side by the hand operation to be transmitted to the tip tip 41. Therefore, in the dilator tube 51, the flat surface 50a is brought into contact with the receiving surface 48 of the distal tip 41 and the distal tip 41 is pushed toward the distal side, thereby extending the catheter tube 31 in the longitudinal direction and expanding the narrow blood vessel. Play a role in.

As shown in FIG. 7, the screw ring 53 has a female screw portion 53A having a thread groove on the inner surface of the inner cavity. The female screw portion 53A corresponds to the second engaged portion in this specification. The screw ring 53 is configured such that the dilator 50 can be attached to the catheter 30 by connecting (engaging) the female screw portion 53A with the male screw portion 36B of the lock connector 36 by screwing as shown in FIG. 7. is doing. The screw ring 53 has an internal space 53B capable of accommodating the cap 37 when the dilator 50 and the catheter tube 31 are connected. The female screw portion 53A of the screw ring 53 is screwed and attached to the male screw portion 36A of the lock connector 36 so that the dilator 50 can be prevented from coming into contact with the cap 37.

In addition, with the above structure, it is possible to prevent the cap 37 from rotating together when the dilator 50 having the screw ring 53 is removed (turned) from the catheter tube 31. Further, the cap 37 is hidden by the screw ring 53 by the above structure. Therefore, a user or the like who uses the dilator 50 for the first time when removing the dilator 50 can easily visually determine which of the cap 37 and the dilator 50 is to be removed first. Therefore, it is possible to prevent the user or the like from mistakenly removing the cap 37 from the catheter tube 31 before the dilator 50, that is, a mistake in the removal order.

<How to use the catheter>
Next, a method of using the catheter 30 described above will be described. 2 shows a state before inserting the dilator tube 51 of the dilator 50 into the lumen 30A of the catheter 30, and FIG. 4 shows a state after inserting the dilator tube 51 into the lumen 30A of the catheter 30.

First, an operator such as a doctor attaches the cap 37 to the lock connector 36 of the catheter 30 by screwing the male screw portion 36A of the lock connector 36 and the female screw portion 37D of the cap 37 into each other as shown in FIGS. In addition to the above, a catheter in which the cap 37 is attached to the lock connector 36 from the beginning may be prepared.

When attaching the dilator 50 to the catheter 30, the operator inserts the dilator tube 51 of the dilator 50 into the lumen 30A of the catheter 30 as shown in FIG. As a result, the dilator tube 51 passes through the insides of the second tube 33 and the first tube 32 in order, and the flat surface 50a of the dilator tube 51 contacts the receiving surface 48 of the tip 41 (see FIG. 9).

Here, as shown in FIG. 2, the total length in the axial direction of the dilator tube 51 is configured to be longer than the total length in the axial direction of the catheter 30. Therefore, the flat tip 50 a of the dilator tube 51 is pressed toward the tip side of the tip tip 41 in a state of being in contact with the receiving surface 48 of the tip tip 41. As a result, the tip of the first tube 32 fixed to the tip 41 is pulled toward the tip side.

As a result, the catheter 30 receives a force in the extending direction, and the first tube 32 of the catheter 30, which has relatively high elasticity, extends in the axial direction. As the first tube 32 extends in the axial direction, the outer diameter of the first tube 32 becomes smaller and becomes substantially the same as the outer diameter of the second tube 33. The operator fixes the male screw portion 36B of the catheter 30 to the female screw portion 53A of the dilator 50 with the first tube 32 extended in the axial direction.

Next, the operator inserts the catheter 30 in which the dilator tube 51 is inserted along a guide wire (not shown) that is previously inserted into the target site in the living body. At this time, by inserting the dilator 50 into the catheter 30, the outer diameter of the first tube 32 becomes substantially the same as the outer diameter of the second tube 33. Therefore, the catheter 30 can be inserted into the living body with minimal invasion. The operator inserts the catheter 30 into the living body and places it until the through holes 46 and 47 of the tip 41 are located in the right atrium and the side hole 63 is located in the inferior vena cava. The first tube 32 is arranged in the inferior vena cava, which is a relatively thick blood vessel, and the second tube 33 is a thigh, which is a relatively thin blood vessel, with the through holes 46, 47 and the side hole 63 being arranged for blood removal. Placed in a vein.

Next, the operator releases the dilator tube 51 and the guide wire from the catheter 30 by unscrewing the male screw portion 36B of the lock connector 36 and the female screw portion 53A of the dilator 50. At this time, the dilator tube 51 and the guide wire are once pulled out to the position of the lock connector 36 of the catheter 30 and clamped by forceps (not shown), and then completely removed from the catheter 30. By removing the dilator tube 51 from the lumen 30A of the catheter 30, the catheter 30 is released from the axially extending force received from the dilator 50. Therefore, the first tube 32 contracts in the axial direction, and the outer diameter and the inner diameter of the first tube 32 increase. As a result, the pressure loss inside the first tube 32 can be reduced.

Next, the operator removes the cap 37 from the lock connector 36 by unscrewing the male screw portion 36A of the lock connector 36 and the female screw portion 37D of the cap 37. Next, the operator connects the lock connector 36 of the catheter 30 to the blood removal tube 11 of the extracorporeal circulation device 1 of FIG. After confirming that the connection of the catheter on the blood supply side is completed, the operator releases the forceps of the clamp tube 34 to start the extracorporeal circulation.

When the extracorporeal circulation is completed, the operator removes the catheter 30 from the blood vessel, and hemostasis is repaired at the insertion site by a surgical procedure as necessary.

As described above, the catheter 30 according to the present embodiment has the catheter tube 31 and the cap 37. The catheter tube 31 is formed in an elongated shape and has a lumen 30A through which blood can flow and through which the dilator 50 can be inserted. The cap 37 is configured to be attachable to and detachable from the catheter tube 31 at the proximal end portion of the catheter tube 31. The dilator 50 is provided with a long dilator tube 51 that can be inserted into the lumen 30A. The cap 37 is provided with a wall surface 37E through which the dilator tube 51 can be inserted while being fitted with the dilator tube 51 of the dilator 50. The lock connector 36 of the catheter tube 31 includes a male screw portion 36B that can be connected and separated from the dilator 50 by being displaced in the circumferential direction with respect to the central axis of the dilator tube 51 in the longitudinal direction.

When the dilator 50 is temporarily attached to the catheter tube 31 by press fitting or fitting, if the dilator 50 is moved in the longitudinal direction to remove the dilator 50 from the catheter tube 31, the position of the catheter tube 31 with respect to the living body may shift. There is.

On the other hand, by thread-connecting the catheter tube 31 and the dilator 50 as described above, it is not necessary to move the dilator 50 directly in the longitudinal direction with respect to the catheter tube 31. Thereby, when the dilator 50 is detached from the catheter tube 31, the positional displacement with respect to the inside of the living body can be eliminated or almost zero. Therefore, it is possible to prevent or suppress the positional displacement of the catheter 30 with respect to the living body when the dilator 50 is removed from the catheter 30 including the cap 37.

Further, the male screw portion 36B is formed in a spiral shape with the longitudinal direction of the dilator 50 as a rotation axis, and the circumferential direction is a spiral direction of the spiral shape. With this configuration, it is possible to prevent or suppress the positional displacement of the catheter 30 with respect to the living body when the dilator 50 is removed from the catheter 30 including the cap 37.

Further, in the present embodiment, the male screw portion 36B is provided on the lock connector 36 connected to the catheter tube 31. The dilator 50 has an internal space 53B and a screw ring 53 connectable to the male screw portion 36B. The cap 37 is configured to be accommodated in the internal space 53B provided in the screw ring 53 in a state where the screw ring 53 of the dilator 50 and the lock connector 36 of the catheter tube 31 are connected.

As a result, the dilator 50 covers the cap 37, and the cap 37 cannot be removed from the catheter tube 31 unless the dilator 50 is removed from the catheter tube 31. Therefore, the order of removing the cap 37 and the dilator 50 can be clarified, and the operability can be improved. Further, by providing the dilator 50 with the internal space 53B that accommodates the cap 37, the dilator 50 can be detached from the lock connector 36 without contacting the cap 37. Accordingly, when the dilator 50 is detached from the catheter 30, the dilator 50 and the cap 37 do not rotate together, so that the cap 37 can be prevented from moving.

Further, in the present embodiment, the male screw portion 36B is provided on the lock connector 36 connected to the catheter tube 31. The lock connector 36 of the catheter tube 31 is configured to include a male screw portion 36A that engages with the cap 37 and a male screw portion 36B that engages with the screw ring 53 of the dilator 50. The cap 37 includes a female screw portion 37D that engages with the male screw portion 36A, and the screw ring 53 of the dilator 50 includes a female screw portion 53A that engages with the male screw portion 36B. Thereby, when the dilator 50 is removed from the catheter 30 including the cap 37, the positional displacement of the catheter 30 with respect to the living body can be prevented or suppressed.

(Second embodiment)
Next, a percutaneous catheter (hereinafter, referred to as “catheter”) 60 according to the second embodiment of the present invention will be described with reference to FIGS. 11 to 13. 11 to 13 are diagrams for explaining the configuration of the catheter 60 according to the second embodiment.

The catheter 60 is a so-called double-lumen catheter, and is configured to be capable of both blood supply and blood removal at the same time. Therefore, in the present embodiment, the catheter 60 in the extracorporeal circulation device 1 in FIG. 1 serves the functions of two catheters, the vein side catheter (blood removal catheter) 5 and the arterial side catheter (blood supply catheter) 6. ..

In the catheter 60 according to the present embodiment, as shown in FIGS. 12 and 13, the double tube in which the third tube 161 including the first lumen 61 communicating with the blood supply side hole 163 is arranged in the lumen of the second tube 33. It differs from the catheter 30 according to the first embodiment in that it has a tubular structure.

According to the catheter 60, the pump of the extracorporeal circulation device 1 is operated to remove blood from the vein (caval vein) of the patient. Then, after performing gas exchange in the blood by the artificial lung 2 to oxygenate the blood, a procedure of a vein-vein system (Veno-Venous, VV) for returning the blood to the patient's vein (caval vein) again is performed. It can be carried out.

Hereinafter, each component of the catheter 60 will be described. It should be noted that the description of the parts common to the first embodiment will be omitted, and the characteristic parts of the present embodiment will be described. It should be noted that parts having the same functions as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 12, the catheter 60 includes a first tube 32, a second tube 33, a distal tip 41 provided at the distal end of the first tube 32 and having through holes 46 and 47, and a second tube 33. And a third tube 161 disposed in the cavity.

As shown in FIG. 12, the catheter 60 has a first lumen 61 that functions as a blood supply path and a second lumen 62 that functions as a blood removal path.

The first lumen 61 is formed in the inner cavity of the third tube 161. The second lumen 62 is formed in the inner cavities of the first tube 32 and the second tube 33 and penetrates from the distal end to the proximal end.

The second tube 33 includes a blood supply side hole 163 that communicates with the first lumen 61 that is a blood supply path, and a blood removal side hole 164 that communicates with the second lumen 62 that is a blood removal path. The blood supply side hole 163 and the blood removal side hole 164 have an elliptical shape, but are not limited thereto.

The third tube 161 is configured to be inserted into the second lumen 62 from the base end side of the second tube 33 and connected to the blood supply side hole 163.

The blood supply side hole 163 is arranged for a blood supply target in the living body. The blood oxygenated by the artificial lung 2 is delivered into the living body through the blood-feeding side hole 163.

The through holes 46 and 47 and the blood removal side hole 164 included in the tip 41 are arranged for different blood removal targets in the living body so that blood removal can be performed efficiently. Further, even if the through holes 46, 47 or the blood removal side hole 164 are adsorbed to the blood vessel wall and blocked, blood can be removed from the hole that is not blocked, so that extracorporeal circulation is stabilized. Can be done by

In the present embodiment, the catheter 60 is inserted from the internal jugular vein of the neck, and the tip thereof is placed in the inferior vena cava via the superior vena cava and the right atrium. The blood supply target is the right atrium, and the blood removal targets are the upper vena cava and the inferior vena cava.

As shown in FIGS. 11 and 12, in the catheter 60, the through holes 46 and 47 of the tip 41 are arranged in the inferior vena cava and the blood removal side hole 164 is arranged in the internal jugular vein with the dilator 50 inserted. Is inserted into the living body and left indwelling.

The first tube 32 is configured to have an inner diameter larger than that of the second tube 33 as in the first embodiment. The first tube 32 is arranged in the inferior vena cava, which is a relatively thick blood vessel, and the second tube 33 is a femoral vein, which is a relatively thin blood vessel, with the through holes 46, 47 and the side hole 63 being arranged for blood removal. Is located in.

The lock connector 136 has a first lock connector 137 and a second lock connector 138 as shown in FIG. The first lock connector 137 is configured to communicate with the first lumen 61, and the second lock connector 138 is configured to communicate with the second lumen 62. The lock connector 136 is configured as a Y-shaped Y connector formed by branching the first lock connector 137 from the second lock connector 138. Although the first lock connector 137 and the second lock connector 138 are brought close to each other in FIG. 12 for convenience of illustration, the first lock connector 137 and the second lock connector 138 are actually separated from each other as compared with FIG. Will be placed.

The first lock connector 137 is connected to the base end portion of the third tube 161. The second lock connector 138 is coaxially connected to the base end portion of the second tube 33. A blood supply tube (blood supply line) is connected to the first lock connector 137, and a blood removal tube (blood removal line) is connected to the second lock connector 138. The first lock connector 137 is provided with a male screw portion 137A at one location. Similar to the first embodiment, the second lock connector 138 has a male screw portion 138A (corresponding to a "first engaging portion") that can be engaged with the cap 37 and a male screw portion 138B ("" that can be engaged with the dilator 50). (Corresponding to "second engaging portion" and "connecting portion").

The 1st tube 32 is comprised so that it may function similarly to 1st Embodiment. When the dilator 50 is inserted through the catheter 60, the first tube 32 expands and its outer diameter and inner diameter become smaller as shown in FIG. As a result, the catheter 60 can be inserted into the living body with minimal invasion. When the dilator 50 is removed from the catheter 30, the first tube 32 contracts and the inner diameter of the first tube 32 increases, as shown in FIG. Thereby, the pressure loss inside the first tube 32 can be reduced.

As described above, according to the catheter 60 according to the present embodiment, one catheter can fulfill both functions of blood removal and blood supply.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims. 14 and 15 are an exploded view and a diagram showing an assembled state for connecting the dilator 50A and the catheter 30B according to a modified example of the present invention.

In the first embodiment, the embodiment in which the male screw portion 36A of the lock connector 36 is screwed with the female screw portion 37D of the cap 37 and the male screw portion 36B is screwed with the female screw portion 53A of the dilator 50 has been described. However, the dilator may be configured to be screwed with the cap as shown in FIGS. 14 and 15 other than the lock connector of the catheter.

14 and 15 differ from the first embodiment in that the screw ring 53C of the dilator 50A does not have the internal space for housing the cap 37 unlike the first embodiment. Further, the cap 37F differs from the first embodiment in that a male screw portion 37G engaging with the dilator 50A is provided on the outer surface of the third hollow portion 37C on the dilator 50A side. The cap 37F includes a female screw portion 37D that engages with the male screw portion 36A of the lock connector 36C of the catheter tube as in the first embodiment.

A female screw portion 53D that can be engaged with the male screw portion 37G is provided on the inner surface of the screw ring 53C of the dilator 50A. The female screw portion 53D is a third engaged portion that engages with the male screw portion 37G of the cap 37F. Equivalent to. The male screw portion 37G is a connecting portion provided on the cap 37F in the present modification, and corresponds to a third engaging portion that engages with the female screw portion 53D of the dilator 50A. The rest of the configuration is the same as that of the first embodiment, so the description is omitted.

With this configuration as well, it is possible to prevent or suppress positional displacement of the catheter 30B with respect to the living body when the dilator 50A is removed from the catheter 30B including the cap 37F.

Moreover, although it has been described that the material of the cap 37 is made of plastic such as hard plastic, the material is not limited to this. In addition to the above, the portion through which the dilator tube 51 is inserted may be made of an elastic member such as rubber or elastomer.

Further, although the catheter tube 31 has been described as being expandable and contractable in the longitudinal direction in the above, the present invention is not limited to this, and one that is not expandable and contractible in the longitudinal direction is also included in one embodiment of the present invention.

30, 30B (percutaneous) catheter,
30A lumen,
31 (catheter) tube,
36, 36C lock connector,
36A, 138A male screw portion (first engaging portion),
36B, 138B male screw portion (second engaging portion, connecting portion),
37, 37F Cap (mounting member),
37E wall surface (fitting part),
37D female screw portion (first engaged portion),
37G male screw part (third engaging part, connecting part),
50, 50A dilator,
51 Dilator tube (insertion part),
53, 53C screw ring (connecting part),
53A female screw portion (second engaged portion),
53D Female screw portion (third engaged portion).

Claims (5)

A long tube that is blood-flowable and has a lumen that allows a dilator to be inserted, and a mounting member that is detachable from the tube at the proximal end of the tube,
The dilator is provided with a long insertion portion that can be inserted into the lumen,
The mounting member includes a fitting portion that can be inserted into the insertion portion while fitting with the insertion portion of the dilator,
The percutaneous catheter, wherein the tube or the attachment member includes a connecting portion that is connectable and separable from the dilator by being displaced in a circumferential direction with respect to a central axis in a longitudinal direction of the insertion portion. The connecting portion has a spiral shape with the rotation axis in the longitudinal direction,
The percutaneous catheter according to claim 1, wherein the circumferential direction is a spiral direction of the spiral shape. In the case where the tube includes the connecting portion,
The dilator has an internal space and is provided with a connecting portion connectable to the connecting portion,
The percutaneous catheter according to claim 1, wherein the attachment member can be housed in the internal space provided in the connecting portion in a state where the connecting portion and the connecting portion are connected. In the case where the tube includes the connecting portion,
The tube includes a first engaging portion that engages with the mounting member, and a second engaging portion that engages with the dilator,
The mounting member includes a first engaged portion that engages with the first engaging portion,
The percutaneous catheter according to claim 1, wherein the dilator includes a second engaged portion that engages with the second engaging portion. In the case where the mounting member includes the connecting portion,
The mounting member includes a first engaged portion that engages with the tube, and a third engaging portion that engages with the dilator,
The tube includes a first engaging portion that engages with the first engaged portion,
The percutaneous catheter according to claim 1, wherein the dilator includes a third engaged portion that engages with the third engaging portion.