Gastrostomy catheter

Abstract

To ease pain during replacement by reducing resistance of insertion / extraction in a bumper-type gastrostomy catheter.SOLUTION: A gastrostomy catheter 10 comprises an external cylinder 10, and an internal cylinder 20 that is inserted into the external cylinder 10. A tip of the external cylinder 10 is provided with a plurality of anchor parts 13 capable of being opened / closed in a radial direction. The internal cylinder 20 is constituted to move in the tip direction of the external cylinder 10 and form a bumper 3 by extending the tip of the anchor part 23 of the external cylinder 10 to the radial outside.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a gastrostomy catheter, and more particularly to a bumper-type gastrostomy catheter. [Background technology]

[0002] Conventionally, gastrostomy catheters that are hooked to the stomach wall and fixed inside the stomach are known as catheters used for gastrostomy. There are two types of gastrostomy catheters of this type: balloon type and bumper type. Balloon type gastrostomy catheters are inserted and removed with the balloon that is hooked to the stomach wall in a deflated state, making them easier to insert and remove than bumper type. However, it is difficult to maintain a stable balloon state for a long period of time, and they have the problem of needing to be replaced more frequently than bumper type.

[0003] Patent Document 1 discloses a bumper-type gastrostomy catheter that includes a cylindrical catheter body with a lumen and a flexible bumper at the tip of the cylindrical catheter body. The catheter of Patent Document 1 is reduced in diameter by inserting a dedicated tool into the catheter body to extend the bumper, which is larger in diameter than the body, and is inserted into the fistula in this state and removed from the fistula. The gastrostomy catheter of Patent Document 1 includes a spherical bumper that expands in the radial direction, and the bumper is stretched using a dedicated tool, so that the bumper expands in the axial direction of the catheter body and deforms into an oblong spheroid shape. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP2019-136138A Summary of the Invention [Problem to be solved by the invention]

[0005] Conventional bumper-type gastrostomy catheters are pulled out of the fistula with the bumper deformed into an oblong spheroid shape, but the diameter of the axial middle part of the bumper is still large, causing pain when replacing. Even with the catheter of Patent Document 1, there is still much room for improvement in terms of reducing resistance when inserting and removing it.

[0006] An object of the present invention is to reduce the resistance to insertion and removal of a bumper-type gastrostomy catheter and to alleviate pain during replacement. [Means for solving the problem]

[0007] The gastrostomy catheter according to the present invention is a tubular gastrostomy catheter having a lumen, comprising an outer tube and an operating member extending in the axial direction of the outer tube, the tip of the outer tube is provided with a plurality of anchor portions that can be opened and closed in the radial direction, and the operating member is configured to move relative to the outer tube and deploy the tips of the anchor portions of the outer tube radially outward to form a bumper.

[0008] According to the above configuration, after the catheter is inserted into the fistula, the tip (anchor portion) of the closed outer tube can be expanded by the operating member to form a bumper that hooks onto the stomach wall. Since the tip of the outer tube is closed in the initial state and has a small outer diameter, it can be smoothly inserted into the fistula. After insertion into the fistula, the operating member moves relative to the outer tube, and the tip of the anchor portion of the outer tube that constitutes the bumper is expanded radially by the operating member. When the catheter is removed from the fistula, the operating member is moved relative to the outer tube and returned to its original position, closing the bumper and reducing the outer diameter of the tip of the outer tube. Therefore, the resistance when inserting and removing the catheter can be effectively reduced, and the pain when replacing the catheter can be sufficiently alleviated.

[0009] In the gastrostomy catheter according to the present invention, it is preferable that the outer cylinder has a plurality of slits or easily breakable portions that separate the anchor portions, the slits or easily breakable portions being formed from the tip of the outer cylinder.

[0010] According to the above configuration, for example, by forming slits so that the bases of multiple anchor parts are connected to each other, it becomes easier to handle the components and the interlocking of each anchor part when it is deployed is improved.

[0011] In the gastrostomy catheter according to the present invention, it is preferable that the operating member is an inner tube inserted into the outer tube, and the inner tube protrudes from a tip of the outer tube to deploy the anchor portion of the outer tube.

[0012] According to the above configuration, by forming the operating member into a cylindrical shape with good moldability, the operating member (inner cylinder) can be stably moved inside the outer cylinder. In other words, it is easy to move the operating member (inner cylinder) along the axial direction of the outer cylinder, and the opening and closing operation of the bumper can be performed smoothly.

[0013] The inner tube may have a slit or easily breakable portion formed at the tip of the inner tube to separate the tip, and the tip may be connected to the anchor portion of the outer tube.

[0014] The outer tube may include a base portion, a first member fitted onto the tip of the base portion, and a cylindrical second member fixed to the base portion via the first member, and the second member may constitute the tip portion of the outer tube where the anchor portion is formed, and be configured to expand when the inner tube is inserted to form the bumper.

[0015] It is preferable that a locking structure is provided at each base end of the outer tube and the inner tube to fix the movement of the inner tube along the axial direction of the outer tube and maintain the inner tube protruding from the tip of the outer tube.

[0016] According to the above configuration, the inner tube can be fixed to the outer tube at the base ends of the outer tube and inner tube located outside the patient's body so that the inner tube does not move, and the inner tube can be stably maintained in the state in which it protrudes from the tip of the outer tube and the bumper is deployed. Effect of the Invention

[0017] According to the present invention, in a bumper-type gastrostomy catheter, the resistance to insertion and removal is reduced, and pain during replacement can be alleviated. [Brief description of the drawings]

[0018] [Figure 1] 1 shows a state in which the gastrostomy catheter of the first embodiment is inserted into a fistula. [Diagram 2] FIG. 1 is a perspective view of the gastrostomy catheter of the first embodiment, showing the bumper in a closed state. [Diagram 3] FIG. 1 is an exploded perspective view of a gastrostomy catheter according to a first embodiment. [Figure 4] 3 is a cross-sectional view taken along line AA in FIG. 2. [Diagram 5] FIG. 1 is a perspective view of the gastrostomy catheter of the first embodiment, showing the state in which the bumper is deployed. [Figure 6] 6 is a cross-sectional view taken along line BB in FIG. 5. [Figure 7] FIG. 13 is a perspective view of a gastrostomy catheter according to a second embodiment, showing the bumper in a closed state. [Figure 8] FIG. 13 is an exploded perspective view of a gastrostomy catheter according to a second embodiment. [Figure 9] 8 is a cross-sectional view taken along line CC in FIG. 7. [Figure 10] FIG. 13 is a perspective view of a gastrostomy catheter according to a second embodiment, showing the bumper in an expanded state. [Figure 11] 11 is a cross-sectional view taken along line DD in FIG. 10. [Figure 12] FIG. 13 is a view for explaining a locking structure for fixing the deployed state of a bumper in a gastrostomy catheter according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. The embodiment described below is merely an example, and the present invention is not limited to the following embodiment. In addition, it is originally assumed that each component of the multiple embodiments described below can be selectively combined.

[0020] [First embodiment] The gastrostomy catheter 1 according to the first embodiment will be described in detail below with reference to FIGS.

[0021] Fig. 1 shows a gastrostomy catheter 1 attached to a patient. As shown in Fig. 1, the gastrostomy catheter 1 includes a tubular section 2 and a bumper 3 provided at one axial end of the tubular section 2, and is fixed to the patient's abdomen by the bumper 3 expanding inside the stomach 100 and catching on the stomach wall 101. The tubular section 2 is inserted into a fistula 104 to form a lumen 4 (see Figs. 4 and 6 described below) which is a flow path through which nutrients and the like pass. One axial end of the tubular section 2 is disposed inside the stomach 100, and the other axial end is positioned on the body surface 103.

[0022] The bumper 3 is a part that hooks onto the stomach wall 101 to prevent the gastrostomy catheter 1 from slipping out of the fistula 104, and is deployed by opening the tip of the tubular section 2 radially outward to become hooked onto the stomach wall 101. In this embodiment, the bumper 3 has three legs that are arranged at substantially equal intervals in the circumferential direction of the tubular section 2, and hooks onto the stomach wall 101 around the fistula 104. The number of legs constituting the bumper 3 is not particularly limited, but is preferably three to six, and more preferably three, from the viewpoints of fixation stability, durability, and the like.

[0023] Gastrostomy is a type of tube feeding medical procedure in which a fistula 104 is formed through a stomach wall 101 and an abdominal wall 102 by a surgical operation, and nutrients and the like are directly supplied to the stomach 100 via a gastrostomy catheter 1 inserted into the fistula 104. The gastrostomy catheter 1 is a bumper-type catheter equipped with a bumper 3, and does not need to be replaced as frequently as a balloon-type catheter, but it does need to be replaced, for example, about four months after it is fitted. As will be described in more detail later, the gastrostomy catheter 1 can effectively reduce the resistance when the catheter is inserted into the fistula 104 and when it is removed from the fistula 104, and can significantly alleviate the pain during replacement.

[0024] The gastrostomy catheter 1 includes a connection unit 25 to which a needleless syringe (not shown) for supplying nutrients or the like is connected. The connection unit 25 is provided at the other axial end of the tubular portion 2, and is placed on the body surface 103. The connection unit 25 has a cap member 26 that opens and closes the lumen 4. When the gastrostomy catheter 1 is not in use, the lumen 4 is closed by the cap member 26. The gastrostomy catheter 1 also has a flange 14 that is provided at the other axial end of the tubular portion 2 and abuts against the periphery of the fistula 104 on the body surface 103. The flange 14 is formed in a plate shape by spreading the other axial end of the outer tube 10 constituting the tubular portion 2 radially outward, and prevents the entire gastrostomy catheter 1 from entering the stomach 100.

[0025] The configuration of the gastrostomy catheter 1 will be described in detail below with reference to Fig. 2 to Fig. 6. Fig. 2 to Fig. 4 show a state in which the bumper 3 is closed, and Fig. 5 and Fig. 6 show a state in which the bumper 3 is unfolded. Fig. 3 is an exploded perspective view of the gastrostomy catheter 1. In this specification, for the gastrostomy catheter 1 and each component of the catheter, the side inserted into the stomach 100 is referred to as the distal end, and the side placed outside the body is referred to as the proximal end.

[0026] As shown in Figs. 2 to 4, the gastrostomy catheter 1 includes an outer tube 10 and an inner tube 20, which is an inserting member inserted into the outer tube 10 as an operating member. A plurality of anchor portions 13 that can be opened and closed in the radial direction are provided independently so as to be separated from each other at the tip portion 11 of the outer tube 10. In this embodiment, a plurality of slits 12 that separate the anchor portions 13 are formed from the tip portion of the outer tube 10. The outer tube 10 and the inner tube 20 form a tubular portion 2 (see Fig. 1), and the respective tip portions 11, 21 become bumpers 3. The tubular portion 2 has a double tube structure consisting of the outer tube 10 and the inner tube 20, and the inner tube 20 is configured to be movable relative to the outer tube 10. In this embodiment, the inner tube 20 that can move along the axial direction of the outer tube 10 forms a lumen 4, and a connection unit 25 to which a syringe or the like for supplying nutrients is connected is provided at the base end portion of the inner tube 20.

[0027] Although the details will be described later, the tip portion 11 (anchor portion 13) of the outer tube 10 is in a closed state when no external force is applied, and has the same outer diameter as the other portion of the outer tube 10 inserted into the fistula 104. Therefore, it is possible to effectively reduce the resistance during insertion and removal, and it is not necessary to use a dedicated tool to reduce the diameter of the bumper as in the case of conventional bumper-type catheters. That is, when the inner tube 20 moves toward the tip of the outer tube 10, the multiple anchor portions 13 of the outer tube 10 are separated, and the tips of the anchor portions 13 are configured to expand radially outward, that is, in a direction away from the central axis, to form bumpers 3 that hook onto the stomach wall 101. In this embodiment, the tip portion 21 of the inner tube 20 is also configured to be expandable, and forms the bumper 3 together with the tip portion 11 of the outer tube 10.

[0028] In the gastrostomy catheter 1, three slits 12 are formed at a predetermined length from the tip of the outer tube 10. The predetermined length is, for example, 5% to 30% of the axial length of the outer tube 10. The three slits 12 are preferably formed parallel to one another with substantially the same length and at equal intervals in the circumferential direction of the outer tube 10. The tip portion 11 of the outer tube 10 is formed with three anchor portions 13, which are parts of the tube wall separated from one another by the three slits 12. Each anchor portion 13 is a portion obtained by dividing the tube wall of the outer tube 10 into three equal parts in the circumferential direction, and together with an anchor portion 23 of the inner tube 20 described later, forms a bumper 3 that hooks onto the stomach wall 103.

[0029] In the gastrostomy catheter 1, a plurality of slits 22 extending in the axial direction are also formed in the tip portion 21 of the inner tube 20. Three slits 22 are formed from the tip of the inner tube 20, and three anchor portions 23 separated by the slits 22 are formed. The slits 22 are preferably formed at positions overlapping the slits 12 of the outer tube 10 in the radial direction of the outer tube 10 (inner tube 20). In addition, one anchor portion 23 overlaps one anchor portion 13 in the radial direction of the tube portion 2, and the respective tip portions are connected to each other. The slits are cutouts that separate each anchor portion, and refer to thin cutouts whose length is longer than the width. Although the size of the anchor portion is reduced, cutouts whose length is approximately the same as or shorter than the width may be formed.

[0030] The anchor portions 13, 23 are separate pieces separated by a slit, and are gently curved to form part of the tube wall. The outer surface of the anchor portion 23 is disposed so as to be in contact with the inner surface of the anchor portion 13, but they are not fixed to each other except at their tips. The pair of anchor portions 13, 23 constitutes one leg of the bumper 3. The legs of the bumper 3 (the pair of anchor portions 13, 23) are linked to each other and are opened and closed simultaneously. The tips of the anchor portions 13, 23 are free ends, and are biased radially inward, i.e., in the closing direction, when the inner tube 20 is in the initial position.

[0031] The gastrostomy catheter 1 further includes a tip tip 30 attached to the tip of the anchor portion 13, 23. The tip tips 30 are provided in the same number as the pair of connected anchor portions 13, 23, and in this embodiment, there are three tip tips. The tip portions of the anchor portions 13, 23 may be connected by attaching the tip tip 30, or the tip portions may be covered with the tip tip 30 after the tip portions of the anchor portions 13, 23 are connected to each other. The tip tip 30 and the anchor portions 13, 23 may be bonded to each other using an adhesive or by welding, or assembled by physical fitting. The tip tip 30 may also be molded integrally with either of the anchor portions 13, 23.

[0032] The distal tip 30 has a rounded outer surface and covers the tip so that the tip of the anchor portion 13, 23 is not exposed. The three distal tips 30 are joined together to form a cone shape with a rounded tip. The outer surface of each distal tip 30 is curved so as to be convex toward the radially outer side of the outer tube 10, and is curved in both the circumferential direction and the axial direction of the outer tube 10. Each distal tip 30 has a shape like a cone divided into three equal parts. The distal end of the catheter consisting of the three distal tips 30 has a tapered shape with the outer diameter gradually decreasing toward the tip. A convex portion 31 and a concave portion 32 are formed on the inner surfaces of each distal tip 30 facing each other. Specifically, a concave portion 32 is formed at a position facing the convex portion 31. The protruding portion 31 fits into the concave portion 32, connecting the distal tips 30 to each other, and the tip of the gastrostomy catheter 1 is more reliably closed.

[0033] A biasing member such as a spring member may be attached to the outer tube so that the tip 11 of the outer tube is biased in the closing direction to close in a natural state. Conversely, the tip 11 of the outer tube may be biased in the deploying direction to deploy in a natural state. A spring hinge may be used so that a bias in the deploying direction occurs when the tip 11 moves beyond a predetermined angle in the deploying direction, and a bias in the closing direction occurs when the tip 11 moves beyond a predetermined angle in the closing direction.

[0034] The outer tube 10, the inner tube 20, and the tip tip 30 are made of, for example, resin. The composition of the resin is not particularly limited, and may be a flexible resin such as silicone elastomer. The tip tip 30 may be made of a resin harder than the outer tube 10 and the inner tube 20. Since the resistance when inserting the catheter is somewhat high, making the tip tip 30 harder than the outer tube 10 and the inner tube 20 makes insertion easier.

[0035] As described above, the flange 14 that abuts against the body surface 103 around the fistula 104 is formed at the base end of the outer tube 10. The flange 14 may be made of a different material from the other parts of the outer tube 10. The shape of the flange 14 in plan view is not particularly limited, and may be a perfect circle, an ellipse, a square, or the like. However, when the flange 14 has a polygonal shape, it is preferable that the corners are rounded. In addition, two locking holes 15 are formed in the flange 14. The locking holes 15 are holes into which the arms 27b described later are inserted, and are formed by penetrating the flange 14 in the thickness direction. A locking structure that fixes the movement of the inner tube 20 along the axial direction of the outer tube 10 is provided at each base end of the outer tube 10 and the inner tube 20. The locking holes 15 and the arm 27b constitute the locking structure. The locking structure may be a locking mechanism that locks via the locking holes or has unevenness such as screwing, but it is preferable that the lock can be released with good operability.

[0036] The inner tube 20 protrudes from the base end of the outer tube 10 when the bumper 3 is closed. The tip ends of the outer tube 10 and the inner tube 20 are connected to each other, and the tip positions of each are substantially aligned. That is, the axial length of the inner tube 20 is longer than the axial length of the outer tube 10. At the base end of the inner tube 20 protruding from inside the outer tube 10, a large diameter portion 24 is formed, the outer diameter of which is larger than the portion inserted into the outer tube 10. The outer diameter of the large diameter portion 24 is larger than the base end opening of the outer tube 10. Therefore, when the inner tube 20 is moved toward the tip end of the outer tube 10, the large diameter portion 24 is caught on the flange 14 formed around the base end opening of the outer tube 10, and the inner tube 20 is not inserted any further.

[0037] A connection unit 25 is attached to the large diameter portion 24 of the inner cylinder 20. The connection unit 25 has a cap member 26 that closes the lumen 4, a lock member 27 that constitutes the lock structure, and a valve body 28. The cap member 26 includes a cylindrical tube portion 26a that is fixed to the large diameter portion 24, and a cap portion 26b that is connected to the tube portion 26a. The tube portion 26a is fitted onto the large diameter portion 24 and constitutes a base portion of the connection unit 25. The valve body 28 is disposed inside the tube portion 26a, and a fixing portion 27a of the lock member 27 is joined to the tube portion 26a.

[0038] The cap member 26 is integrally formed with the tube portion 26a and the cap portion 26b so that the cap is not lost when the lumen 4 is opened, and the cap portion 26b is connected to the tube portion 26a via a flexible, elongated connecting portion. The valve body 28 is a cylindrical body whose diameter gradually decreases toward the tip side of the inner tube 20, and its inner peripheral surface is formed in a tapered shape. The cap portion 26b has a triangular pyramid-shaped convex portion that fits closely to the tapered surface of the valve body 28. The convex portion of the cap portion 26b is inserted into the tube of the valve body 28 to block the opening of the valve body 28 and close the base end of the lumen 4. A syringe that supplies nutrients is also inserted into the tube of the valve body 28, similar to the cap portion 26b.

[0039] The locking member 27 includes a fixed portion 27a fixed to the tubular portion 26a and a pair of arms 27b extending from the fixed portion 27a. The fixed portion 27a is formed in a ring or cylindrical shape so as not to block the opening of the tubular portion 26a. The pair of arms 27b are disposed so as to face each other in the radial direction of the fixed portion 27a and extend from the fixed portion 27a along the axial direction of the inner tube 20. The arms 27b are formed in an elongated plate shape and elastically deform in the radial direction of the fixed portion 27a. Therefore, when the arms 27b are pressed from the radial outside toward the inside, the tip portions of the arms 27b move radially inward.

[0040] The arm 27b is longer than the axial length of the tube portion 26a and is formed with a length that allows insertion into the locking hole 15 of the flange 14 when the inner tube 20 is moved toward the tip end of the outer tube 10. A claw 27c that protrudes in a direction away from each other is formed at the tip of each arm 27b. The tip of the arm 27b is inserted into the locking hole 15 and the claw 27c is hooked on the periphery of the locking hole 15, thereby locking the movement of the inner tube 20 along the axial direction of the outer tube 10. Since the arm 27b is elastically deformed, the arm 27b can be removed from the locking hole 15 and the lock can be released by pulling the connection unit 25 toward the base end side while the arm 27b is pressed inward and bent.

[0041] Hereinafter, the configuration of the bumper 3 will be described in detail with further reference to FIGS.

[0042] 5 and 6, the gastrostomy catheter 1 is configured such that the inner tube 20 moves toward the distal end of the outer tube 10, and the distal end of the anchor portion 13 of the outer tube 10 is deployed radially outward to form a bumper 3 that hooks onto the stomach wall 101. In this embodiment, the distal end of the anchor portion 23 of the inner tube 20 is connected to the distal end of the anchor portion 13 of the outer tube 10, and a distal tip 30 is attached to the distal end of the anchor portions 13, 23. When the inner tube 20 moves toward the distal end of the outer tube 10, the anchor portion 23 expands radially outward so as to push up the connected anchor portion 13, and together with the anchor portion 13, forms the bumper 3 in the deployed state.

[0043] When the bumper 3 is deployed, the inner tube 20 protrudes from the tip of the outer tube 10. As described above, the base ends of the outer tube 10 and the inner tube 20 are provided with a locking structure that fixes the movement of the inner tube 20 along the axial direction of the outer tube 10 and maintains the state in which the inner tube 20 protrudes from the tip of the outer tube 10. The inner tube 20 is locked so as not to move in the axial direction when the tip of the arm 27b is inserted into the locking hole 15 of the flange 14 and the claw 27c formed at the tip of the arm 27b is caught on the periphery of the locking hole 15. This maintains the deployed state of the bumper 3.

[0044] The anchor parts 13, 23 are formed to be bendable like a hinge. The anchor parts 13, 23 are, for example, bent by elastic deformation and are biased toward the radially inward direction of the tubular part 2 so as to return to their natural state. That is, when the lock of the inner tube 20 is released and the force that deploys the anchor parts 13, 23 is no longer acting, the anchor parts 13, 23 move toward the radially inward direction and the inner tube 20 moves toward the base end direction. This brings the bumper 3 into a closed state, and the gastrostomy catheter 1 can be easily removed from the fistula 104.

[0045] The hinge may be formed by providing a thin portion between the base end side and the tip end side of the outer cylinder, or the base end side and the tip end side of the outer cylinder may be separate members and a rotation axis may be provided by a pin and a hole into which the pin is inserted, so that the respective members rotate relatively. Also, the base end side and the tip end side of the outer cylinder may be separate members and a bendable fixing member may be provided between the base end side and the tip end side of the outer cylinder so that the base end side of the outer cylinder and the member on the tip side of the outer cylinder rotate.

[0046] The anchor portion 13 of the outer tube 10 is bent at its base so as to be approximately perpendicular to the outer peripheral surface of the outer tube 10 located on the base end side of the anchor portion 13. The anchor portion 13 is deployed so as to be pushed up by the anchor portion 23 of the inner tube 20. The base of the anchor portion 13 is located, for example, on a line connecting the base ends of the two slits 12 along the circumferential direction of the tube wall of the outer tube 10. In this embodiment, a groove 16 is formed at the base of the anchor portion 13 along the circumferential direction of the tube wall. The groove 16 is formed on the outer peripheral surface of the outer tube 10 so as to connect the multiple slits 12, making it easy to bend the anchor portion 13.

[0047] The angle θ1 between the outer surface of the anchor portion 13 and the outer peripheral surface of the outer tube 10 located on the base end side of the anchor portion 13 is preferably 70° or more and 130° or less, more preferably 80° or more and 120° or less, and may be 110°±5°, from the viewpoint of the fixing stability of the bumper 3. This angle may be smaller at the tip of the anchor portion 13 to which the tip tip 30 is attached. The anchor portion 13 has a substantially constant thickness from its base to the vicinity of the tip. A predetermined length range from the tip of the anchor portion 13 is thinned and the width is also slightly smaller. In addition, a step is formed on the outer surface at the tip of the anchor portion 13.

[0048] The anchor portion 23 of the inner tube 20 is bent at a base end portion thereof so that the base end portion is located closer to the tip end than the outer tube 10 and the base end portion is bent at an angle smaller than a right angle with respect to the outer peripheral surface of the inner tube 20 located closer to the base end than the anchor portion 23. That is, the bent portion of the inner tube 20 is located closer to the tip end than the bent portion of the outer tube 10. The base of the anchor portion 23 is located, for example, on a line connecting the base ends of the two slits 22 along the circumferential direction of the tube wall of the inner tube 20. No groove is formed along the circumferential direction of the tube wall at the base of the anchor portion 23, but the thickness of the anchor portion 23 gradually increases toward the tip. By thickening the anchor portion 23, it becomes easier to push up the anchor portion 13.

[0049] The anchor portion 23 is thickened by its inner surface protruding toward the radial inside of the inner tube 20. Therefore, a step is formed at the base portion of the inner surface of the anchor portion 23, and this step makes it easy to bend the anchor portion 23. The angle θ2 between the outer surface of the anchor portion 23 and the outer peripheral surface of the inner tube 20 located on the base end side of the anchor portion 23 is preferably 30° to 80°, more preferably 45° to 75°. The tip of the inner tube 20 protrudes from inside the outer tube 10, and the anchor portion 23 is bent at the base to push up the anchor portion 13, so the angle θ2 is smaller than the angle θ1.

[0050] The anchor portion 23 is thinned over a certain length from its tip, and its width is also slightly reduced. A step is formed on the inner surface of the tip of the anchor portion 23. A tip tip 30 is fitted onto the thinned tip portions of the anchor portions 13, 23, and the tips are connected to each other. Since the anchor portions 13, 23 are not fixed except for their tips, when the bumper 3 is deployed, the distance between the anchor portions 13, 23 gradually increases toward the base portion. The deployed bumper 3 is composed of three sets (legs) of anchor portions 13, 23 arranged at equal intervals in the circumferential direction of the pipe portion 2, as described above.

[0051] The axial length of the anchor portion 23 is longer than the axial length of the anchor portion 13. That is, the slit 22 of the inner tube 20 is formed longer than the slit 12 of the outer tube 10. By making the axial length of the anchor portion 13 smaller than the axial length of the anchor portion 23, it becomes easier to push up the anchor portion 13 by protruding the inner tube 20 from the tip of the outer tube 10. The three anchor portions 13 have the same dimensions. Similarly, the three anchor portions 23 have the same dimensions.

[0052] As shown in Figs. 2 and 4, the gastrostomy catheter 1 is inserted into the fistula 104 with the anchor parts 13, 23 closed and the tip tips 30 connected to each other. The gastrostomy catheter 1 is removed from the fistula 104 with the anchor parts 13, 23 closed. The anchor parts 13, 23 are biased in the closing direction, and when the arm 27b is removed from the locking hole 15 of the locking structure to release the lock on the inner tube 20, the tips of the anchor parts 13, 23 move in a direction approaching each other, and the bumper 3 closes. Alternatively, the inner tube 20 can be displaced in the base end direction relative to the outer tube 10 to move the anchor parts 23 and the anchor parts 13 fixed to the anchor parts 23 in a direction to close inward, thereby closing the bumper 3. That is, the bumper 3 can be closed by simply releasing the lock on the inner tube 20 without using a special tool.

[0053] As shown in Figures 1, 5, and 6, the gastrostomy catheter 1 is configured such that, after the anchor portions 13, 23 are inserted into the fistula 104 in a closed state, the inner tube 20 is moved toward the distal end of the outer tube 10, i.e., in the direction of insertion into the body, so that the bumper 3 is deployed. When the inner tube 20 is pushed toward the distal end of the outer tube 10, the inner tube 20 protrudes from inside the outer tube 10, and the anchor portions 23 spread radially outward, pushing up the anchor portions 13 whose distal ends are connected to each other. At this time, the arm 27b provided at the base end of the inner tube 20 is inserted into the locking hole 15 of the flange 14 provided at the base end of the outer tube 10, locking the movement of the inner tube 20 and maintaining the bumper 3 in the deployed state.

[0054] As described above, with the bumper-type gastrostomy catheter 1, the tip of the tubular section 2 is initially closed and has a small outer diameter, so there is little resistance when inserting it into the fistula 104 and when removing it from the fistula 104, and pain when replacing the catheter can be alleviated. Furthermore, with the gastrostomy catheter 1, the bumper 3 can be deployed using the inner tube 20 that constitutes the lumen 4 through which liquids such as nutrients to be supplied to the body pass. Therefore, no special tools are required when inserting or removing the catheter.

[0055] [Second embodiment] The gastrostomy catheter 5 according to the second embodiment will be described in detail below with reference to Figs. 7 to 12. Differences from the first embodiment will be mainly described below. Figs. 7 to 9 show a state in which the bumper 7 is closed, and Figs. 10 and 11 show a state in which the bumper 7 is deployed. Fig. 8 is an exploded perspective view of the gastrostomy catheter 5.

[0056] As shown in Figs. 7 to 9, the gastrostomy catheter 5 is common to the gastrostomy catheter 1 of the first embodiment in that it is a bumper-type catheter equipped with an outer tube 50 having a plurality of axially extending slits 54a formed at a tip portion 52, and an inner tube 60 which is an insertion member inserted into the outer tube 50. The outer tube 50 and the inner tube 60 form a tubular section 6 having a double-tube structure, and the internal space of the inner tube 60 forms a lumen 8 which is a flow path through which nutrients and the like pass. The base end of the inner tube 60 has a structure that allows a needleless syringe to be connected. The inner tube 60 is configured to move toward the tip of the outer tube 50 and expand the tip portion 52 of the outer tube 50 to form a bumper 7.

[0057] The tip portion 52 of the outer tube 50, like the outer tube 10 of the gastrostomy catheter 1, is in a closed state when no external force is applied, and has the same outer diameter as the other portion of the outer tube 50 inserted into the fistula 104. This effectively reduces resistance during insertion and withdrawal, and eliminates the need to use a dedicated tool to reduce the diameter of the bumper as in conventional bumper-type catheters. In addition, the tip portion 52 of the outer tube 50 is formed with three slits 54a at a predetermined length from the tip, and three anchor portions 54b separated from each other by the slits 54a. The three anchor portions 54b are formed by dividing the outer tube 50 into three equal parts in the circumferential direction, and have the same shape and dimensions.

[0058] On the other hand, the outer tube 50 differs from the outer tube 10 of the gastrostomy catheter 1 in that it includes a base member 51, a first member 53 fitted onto the tip of the base member 51, and a cylindrical second member 54 fixed to the base member 51 via the first member 53. That is, the tip portion 52 of the outer tube 50 constituting the bumper 7 is formed of a separate member from the other portion on the base end side of the tip portion 52. The second member 54 constitutes the tip portion 52 of the outer tube 50 in which a slit 54a is formed, and is configured to expand to form the bumper 7 when the inner tube 60 is inserted into the tube of the second member 54, as will be described in detail later.

[0059] The gastrostomy catheter 5 is configured such that the second member 54 expands radially outward when the inner tube 60 is inserted into the second member 54, and the second member 54 closes when the inner tube 60 is removed from the second member 54. That is, the bumper 7 that unfolds and hooks onto the stomach wall 101 is composed solely of the tip portion 52 of the outer tube 50, which is different from the gastrostomy catheter 1. The tip portion 62 of the inner tube 60 does not have a slit or easily breakable portion and does not expand radially outward. The inner tube 60, like the outer tube 50, includes a base member 61 and a tip portion 62, and the tip portion 62 is composed of a separate member from the tube portion 61a on the base end side. The tube portion 61a is inserted into the base member 51 to form the lumen 8.

[0060] The outer tube 50 further includes a flange 55 attached to the base end of the base member 51. The base member 51 is a cylindrical member and is a portion that is mainly disposed within the fistula 104 when the gastrostomy catheter 5 is fixed to the patient's abdomen. The flange 55 abuts against the body surface 103 around the fistula 104. In this embodiment, the flange 55 has a planar shape in which a part of an elliptical arc protrudes radially outward. The flange 55 is formed with a through hole 56 that exposes the base end opening of the base member 51, and a pair of hooks 57 that are disposed to sandwich the through hole 56.

[0061] A lock structure is provided at each base end of the outer tube 50 and the inner tube 60 to prevent the inner tube 60 from moving along the axial direction of the outer tube 50, and the hook portion 57 constitutes the lock structure together with the lock member 63 of the inner tube 60. A large diameter portion 61b larger than the base end opening of the outer tube 50 is formed at the base end of the base member 61, and the lock member 63 is attached to the large diameter portion 61b. The lock member 63 has an engagement protrusion 63a protruding radially outward from the inner tube 60. The engagement protrusion 63a is caught by the hook portion 57 of the flange 55 to lock the inner tube 60 from moving. The hook portion 57 is erected on the surface of the flange 55 and has a shape capable of holding the engagement protrusion 63a.

[0062] The inner tube 60 further includes a cap portion 61c that closes the lumen 8, a cover member 64 that covers the locking member 63, and a valve body 65. The cap portion 61c is, for example, integrally molded with the base member 61 and connected to the large diameter portion 61b via a flexible, elongated connecting portion. A biasing portion 61d that presses the locking member 63 radially outward is formed on the outer circumferential surface of the large diameter portion 61b at a position radially opposite to the connecting portion of the cap portion 61c. A support portion 61e that protrudes radially outward is formed on the large diameter portion 61b so as to sandwich the biasing portion 61d in a plan view. The support portion 61e is a portion on which the locking member 63 is placed, and is formed in a plate shape protruding from the outer circumferential surface of the large diameter portion 61b.

[0063] The locking member 63 is a member having a substantially U-shape in a plan view, and is disposed on the support portion 61e so as to sandwich the large diameter portion 61b. The locking member 63 has engagement protrusions 63a formed on both ends of the U-shape. In addition, a convex portion 63b protruding in a direction perpendicular to the protruding direction of the engagement protrusion 63a is formed at a position equidistant from the engagement protrusion 63a. The locking member 63 is disposed so that the convex portion 63b and the biasing portion 61d formed on the outer circumferential surface of the large diameter portion 61b are aligned in the radial direction of the inner tube 60. Although the details will be described later, the convex portion 63b is a portion pressed by a syringe or the like, and when the convex portion 63b is pressed, the locking member 63 moves in the radial direction of the inner tube 60 against the biasing force of the biasing portion 61d.

[0064] The cover member 64 is a member that covers the large diameter portion 61b and the locking member 63, and has a cylindrical main body portion 64a. The main body portion 64a is fixed to the cylindrical wall of the large diameter portion 61b with a space that allows the locking member 63 to move. A cylindrical syringe insertion portion 64b that protrudes radially outward is formed on the outer circumferential surface of the main body portion 64a. The convex portion 63b of the locking member 63 is accommodated in the cylinder of the syringe insertion portion 64b, and is pressed by inserting a syringe or the like into the syringe insertion portion 64b. The valve body 65 has a shape similar to that of the valve body 28 of the first embodiment, and is disposed in the large diameter portion 61b. The valve body 65 is, for example, sandwiched between the cylindrical wall of the large diameter portion 61b and the cover member 64.

[0065] Hereinafter, the configurations of the tip portions 52, 62 of the outer cylinder 50 and the inner cylinder 60, and the bumper 7 will be described in detail with further reference to FIGS.

[0066] 10 and 11, the gastrostomy catheter 5, like the gastrostomy catheter 1, is configured such that the inner tube 60 constituting the lumen 8 moves toward the distal end of the outer tube 50, deploying the anchor portion 54b of the outer tube 50 to form a bumper 7 that hooks onto the stomach wall 101. The inner tube 60 also protrudes from the distal end of the outer tube 50 to deploy the distal end portion 52 (anchor portion 54b) of the outer tube 50. Specifically, the inner tube 60 is inserted into the tube of the second member 54 constituting the distal end portion 52, and the anchor portion 54b is pressed from within the tube to deploy it.

[0067] As described above, the tip portion 52 of the outer tube 50 is composed of the first member 53 and the second member 54. The first member 53 is a member for fixing the second member 54 to the base member 51, and is formed in a substantially cylindrical shape when the bumper 7 is closed. The first member 53 is fitted onto the base member 51 and the second member 54, but in order to prevent the outer diameter of the outer tube 50 from becoming large, for example, a groove-shaped recess is formed along the circumferential direction on the outer peripheral surfaces of the parts of the base member 51 and the second member 54 that are covered by the first member 53. The first member 53 and the second member 54 are bonded together, for example, by using an adhesive or by welding.

[0068] The first member 53 spreads radially outward together with the second member 54. The first member 53 connects the base member 51 and the second member 54 so that the second member 54 does not come off from the base member 51 even when the bumper 7 is deployed. The first member 53 is preferably made of a flexible material such as an elastomer so that it does not hinder the deployment of the anchor portion 54b and is easily deformed with the opening and closing of the anchor portion 54b. The first member 53 is, for example, a member in which a sheet of silicone elastomer or the like is molded into a cylindrical shape. For example, the first member 53 is folded in a state in which the second member 54 is closed, and a part of the first member 53 is inserted into the cylindrical interior of the second member 54 through the slit 54a. The first member 53 spreads so as to come into surface contact with the stomach wall 101 as the second member 54 is deployed.

[0069] The second member 54 is a cylindrical body having an outer diameter equal to or smaller than that of the base member 51, and has a tapered shape that gradually decreases in diameter toward the tip. The tip of the second member 54 is rounded so that the gastrostomy catheter 5 is inserted without causing any pain. The second member 54 has three slits 54a formed along the axial direction with the same length from the tip, and three anchor portions 54b separated by the slits 54a are formed. The second member 54 further has a ring portion 54c that connects the base ends of the anchor portions 54b to each other. The ring portion 54c may not be provided, and the three anchor portions 54b may be fixed to the first member 53 independently.

[0070] The anchor portion 54b forms the outer peripheral surface of the second member 54 and protrudes into the tube of the second member 54. The anchor portion 54b protrudes to a region through which the tip portion 62 of the inner tube 60 inserted into the tube of the second member 54 passes so as to be pressed by the tip portion 62 of the inner tube 60. The anchor portion 54b has, for example, a substantially triangular shape in a plan view (see FIG. 8). The anchor portion 54b is rotated and spread outward in the radial direction by being pressed from the base end side by the tip portion 62 of the inner tube 60, and becomes in a state substantially perpendicular to the outer peripheral surface of the tip portion 62. At this time, the base end surface of the anchor portion 54b abuts against the outer peripheral surface of the tip portion 62. This stably maintains the state in which the anchor portion 54b spreads outward in the radial direction, i.e., the bumper 7 is deployed. The second member 54 is made of, for example, a resin harder than the first member 53.

[0071] The tip portion 62 is composed of a cylindrical member fixed to the tip portion of the base member 61. The tip portion 62 is a cylindrical body having an outer diameter similar to that of the tube portion 61a of the base member 61, and does not have a slit or an easily breakable portion. The tip portion 62 is made of, for example, a resin harder than the base member 61 in order to press and deploy the anchor portion 54b. The base member 61 may be made of a flexible resin such as an elastomer. In this embodiment, the outer peripheral surface of the tip portion 62 is a tapered surface in which the outer diameter gradually decreases toward the tip. In this case, it becomes easy to insert the tip portion 62 into the tube of the second member 54.

[0072] As shown in Fig. 7 and Fig. 9, the gastrostomy catheter 5 is inserted into the fistula 104 with the anchor portion 54b (bumper 7) closed. The gastrostomy catheter 5 is removed from the fistula 104 with the anchor portion 54b closed. The anchor portion 54b is forcibly deployed by the insertion of the tip portion 62, so that when the pressing force of the tip portion 62 is released, the anchor portion 54b returns to a closed state along the axial direction of the outer tube 50. That is, the anchor portion 54b is biased radially inward. Therefore, the bumper 7 can be closed by simply unlocking the inner tube 60 without using a special tool.

[0073] 10 and 11, the gastrostomy catheter 5 is configured such that after the anchor portion 54b is inserted into the fistula 104 with the anchor portion 54b closed, the inner tube 60 is moved toward the distal end of the outer tube 50 to deploy the bumper 7. When the inner tube 60 is pushed toward the distal end of the outer tube 50, the distal end 62 of the inner tube 60 is inserted into the second member 54 of the outer tube 50, and the anchor portion 54b is pressed from within the tube and pushed outward in the radial direction. At this time, the engaging projection 63a of the locking member 63 is hooked onto the hook portion 57 of the flange 55 to lock the movement of the inner tube 60, and the bumper 7 is maintained in the deployed state.

[0074] Hereinafter, the locking structure of the inner cylinder 60 will be described in detail with reference to Fig. 12. In Fig. 12, in order to clearly show the locking member 63, the portion of the cover member 64 that covers the locking member 63 is not shown.

[0075] Fig. 12(a) shows the inner tube 60 in a locked state, and Fig. 12(b) shows the inner tube 60 in an unlocked state. As shown in Fig. 12(a), the inner tube 60 is pushed toward the tip of the outer tube 50, and the engagement protrusion 63a of the locking member 63 is caught by the hook portion 57 of the flange 55, thereby locking the movement of the inner tube 60 and maintaining the deployed state of the bumper 7. At this time, the locking member 63 is pushed by the biasing portion 61d formed on the outer circumferential surface of the large diameter portion 61b, and the protrusion 63b is housed in the syringe insertion portion 64b of the cover member 64.

[0076] As shown in Fig. 12(b), by inserting a syringe into syringe insertion portion 64b and pressing convex portion 63b, convex portion 63b of locking member 63 moves in a direction approaching large diameter portion 61b against the biasing force of biasing portion 61d, and engaging protrusion 63a comes off hook portion 57. This releases the lock on inner tube 60, allowing inner tube 60 to move in the base end direction. Hook portion 57 is formed in a hook shape so that engaging protrusion 63a can be caught, but there is no wall that stops the movement of engaging protrusion 63a in the direction in which convex portion 63b is pressed (see Fig. 8), and convex portion 63b can be released from hook portion 57.

[0077] Like the gastrostomy catheter 1, the tip of the tubular portion 6 of the gastrostomy catheter 5 is initially closed and has a small outer diameter, so there is little resistance when inserting it into the fistula 104 and when removing it from the fistula 104, and pain when replacing the catheter can be reduced. In addition, the bumper 7 can be deployed using the inner tube 60 that constitutes the lumen 8 through which liquids such as nutrients to be supplied to the body pass, so no special tools are required when inserting or removing the catheter.

[0078] The above-mentioned embodiments can be appropriately modified in design without impairing the object of the present invention. For example, in the above-mentioned embodiments, the outer tubes 10, 50 are exemplified with slits 12, 54a formed from the tip along the axial direction, but the outer tube may have an easily breakable portion instead of a slit. The easily breakable portion is a portion that is easily cut by moving the insert member toward the tip of the outer tube, and is formed in the same manner as a slit. The easily breakable portion is formed, for example, by a half-cut line, a perforation line, a notch, or the like.

[0079] In addition, in each of the above embodiments, the inner tube 20, 60 is exemplified as an inserting member inserted into the outer tube, but it is also possible to use an inserting member that is not cylindrical. For example, a wire inserted into the outer tube may be used as the inserting member, or a wire connected to the anchor part of the outer tube may be attached to the inner tube. In addition, a configuration is also conceivable in which a wire passage such as a groove is provided on the outer surface side of the outer tube, a wire connected to the tip of the outer tube is provided as an operating member in the wire passage, and the anchor part of the outer tube is deployed by pulling the wire in the proximal direction. In addition, the inserting member may be removable from the outer tube. [Explanation of symbols]

[0080] [First embodiment] 1 gastrostomy catheter, 2 tube portion, 3 bumper, 4 lumen, 10 outer tube, 11 tip portion, 12 slit, 13 anchor portion, 14 flange, 15 engagement hole, 16 groove, 20 inner tube, 21 tip portion, 22 slit, 23 anchor portion, 24 large diameter portion, 25 connection unit, 26 cap member, 26a tube portion, 26b cap portion, 27 lock member, 27a fixing portion, 27b arm, 27c claw, 28 valve body, 30 tip tip, 31 convex portion, 32 concave portion, 100 stomach, 101 stomach wall, 102 abdominal wall, 103 body surface, 104 fistula

[0081] [Second embodiment] 5 Gastrostomy catheter, 6 Tube portion, 7 Bumper, 8 Lumen, 50 Outer tube, 51 Base portion, 52 Tip portion, 53 First member, 54 Second member, 54a Slit, 54b Anchor portion, 54c Ring portion, 55 Flange, 56 Through hole, 57 Hook portion, 60 Inner tube, 61 Base member, 61a Tube portion, 61b Large diameter portion, 61c Cap portion, 61d Pressing portion, 62 Tip portion, 63 Lock member, 63a Engagement protrusion, 63b Convex portion, 64 Cover member, 64a Main body portion, 64b Syringe insertion portion, 65 Valve body

Claims

1. A tubular gastrostomy catheter having a lumen, An outer cylinder, An operating member extending in an axial direction of the outer cylinder; Equipped with A plurality of anchor portions that can be opened and closed in the radial direction are provided at the tip portion of the outer cylinder, The operating member is configured to move relative to the outer cylinder and to deploy a tip of the anchor portion of the outer cylinder radially outward to form a bumper.

2. The gastrostomy catheter according to claim 1 , wherein the outer tube has a plurality of slits or easily breakable portions formed from a tip of the outer tube to separate the anchor portions.

3. The operating member is an inner cylinder inserted into the outer cylinder, The gastrostomy catheter according to claim 1 or 2, wherein the inner tube protrudes from a tip of the outer tube to deploy the anchor portion of the outer tube.

4. The gastrostomy catheter according to claim 3, wherein the inner tube has a slit or easily breakable portion formed at the tip of the inner tube that separates the tip, and the tip is connected to the anchor portion of the outer tube.

5. the outer cylinder includes a base portion, a first member fitted onto a tip portion of the base portion, and a cylindrical second member fixed to the base portion via the first member, The gastrostomy catheter according to claim 3, wherein the second member constitutes the tip portion of the outer tube on which the anchor portion is formed, and is configured to expand when the inner tube is inserted to form the bumper.

6. The gastrostomy catheter according to any one of claims 3 to 5, wherein a lock structure is provided at each base end of the outer tube and the inner tube, which fixes movement of the inner tube along the axial direction of the outer tube and maintains a state in which the inner tube protrudes from the tip of the outer tube.

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