JP2006239236A - Sheath for inserting catheter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheath for inserting a catheter with which puncturing can be carried out thinly, an inner diameter for inserting the catheter is kept until insertion of the catheter after removal of a puncture needle, and the inner diameter can easily be expanded in the case of inserting the catheter. <P>SOLUTION: The sheath for inserting the catheter is composed of: a tubular member 30 with one or more cuts extending along an axial direction, and a flexible and elastic member 40 which bridges the cuts and which is more flexible and elastic than the tubular member 30. The sheath can be deformed from a state of contracting the tubular member 30 so as to close the cuts to an expanding state of opening the cuts while stretching the flexible and elastic member 40. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sheath for inserting a catheter into a body in the medical field, and more particularly to a sheath for inserting a catheter in a transendoscopic gastrostomy.

Transendoscopic gastrostomy (PEG) is one of the most safe and safe methods among tube feeding methods for patients who have difficulty in voluntary oral intake of nutrition. Are known. When this method is used, a tube or the like is not fixed to the face as in the case of the nasal tube method, and the psychological burden on the patient can be greatly reduced, and care can be simplified.
One such technique in PEG is the Introducer method. This is effective in terms of hygiene and technique efficiency because the number of insertions of the endoscope is small compared to other techniques. In this method, in order to construct a catheter, a puncture needle is inserted into the sheath, and the stomach is percutaneously inserted into the stomach. After removing the puncture needle, the catheter is introduced through the sheath and inserted into the stomach. I do.

When this method is used, it is preferable to make the sheath thinner in order to reduce the burden on the patient during puncture, while the catheter that is a nutrient supply medium is also used for viscous infusion, so the inner diameter should be larger. preferable. In order to achieve both of these, a sheath made of a soft elastic member is used throughout so that the sheath can be made thin at the time of puncture and the inner diameter can be increased at the time of catheter insertion. Has been proposed (for example, Patent Document 1).
JP-T 9-512732 Publication

  However, in the case of a sheath made entirely of a soft elastic member as in Patent Document 1, the sheath receives a pressing force from the skin and muscles until the catheter is inserted after the puncture needle is pulled out, and the diameter is reduced. In addition, there may be a case of obstruction. Thus, if the diameter is reduced before the catheter is inserted, it becomes difficult to insert the catheter into the stomach. In particular, with the use of a thin puncture needle in consideration of reducing the burden on the patient, the sheath itself becomes thin, and it becomes difficult to insert the catheter.

In this way, when it is intended to ensure the sheath inner diameter necessary for insertion of the catheter, a new pressure is applied to the range subjected to the pressing force (hereinafter referred to as “pressured portion”). However, when such a measure is used, the burden on the patient may increase as a result.
The present invention has been made in view of the above problems, and can be pierced in a thin state at the time of piercing, and the inner diameter into which the catheter can be inserted after the piercing needle is pulled out until the catheter is inserted. An object of the present invention is to provide a catheter insertion sheath that can be maintained and can easily expand its inner diameter during catheter insertion.

In the present invention, the following means are used to solve the above problems.
A catheter insertion sheath, a tubular member having at least one cut extending in the axial direction in a range to be inserted into the body, and a softer elastic member than the tubular member (hereinafter, referred to as bridge) And is configured to be deformable from a state in which the tubular member is contracted so as to close the cut line to an expanded state in which the soft elastic member is extended and the cut line is opened. In addition, even if the pressing force from the outside acts, the said tubular member shall be able to prevent that a to-be-pressed part contracts extremely rather than the said contracted state. Here, the pressing force from the outside is, for example, pressure from the abdominal wall or stomach wall received by the sheath after the sheath is pierced and the puncture needle is pulled out.

The tubular member is formed, for example, so as to have a single cut and a C-shaped cross section.
Further, it is preferable that the tubular member has a configuration in which a part of the peripheral portion is formed thin and bends around the thin portion when the diameter is reduced. The thin-walled portion preferably has a shape formed with a semi-elliptical cutout portion, particularly a plurality of cutout portions.
Based on these, for example, the following configuration can be adopted.

First, it is preferable to connect the soft elastic member having a band shape in a state in which a part of the end of the tubular member facing the cut is overlapped.
Moreover, it is also preferable to make it the structure coated with the tubular member which has hard elasticity, leaving the said cut | disconnection applicable part of the periphery part of a cylindrical soft elastic member.
In addition, it is also preferable to adopt a configuration in which a cylindrical soft elastic member is closely fitted to the inner periphery of the tubular member.

In addition to the above-described contents, the following means can be used for the catheter insertion sheath.
The sheath for catheter insertion is configured such that the sheath body is formed by winding an elastic plate in a spiral shape, and can slide in the circumferential direction of the elastic plate to change the diameter of the sheath body.
In that case, it is preferable that the sheath body has a reduced diameter state or a state close thereto in a state where no external force is applied. It should be noted that the elastic plate material can be prevented from being extremely contracted as compared with the above-mentioned reduced diameter state even when a pressing force from the outside acts.

  When inserting the catheter into the catheter insertion sheath, it is preferable to use a catheter guide in which one end portion has a protruding shape and the inner peripheral surface thereof has a curved shape.

  According to the catheter insertion sheath of the present invention, since there is a cut in the tubular member in the insertion range, the tubular member can be deformed into a contracted state and an expanded state even if a relatively rigid material is used. Since the cut is cross-linked by the soft elastic member, even if the tubular member expands and a gap is generated in the cut portion, the gap is closed by the soft elastic member. Therefore, when the puncture needle is pierced through the sheath, the tubular member is contracted so as to close the cut, so that the burden on the patient can be reduced. In addition, the sheath is subjected to a pressing force on the abdominal wall and stomach wall in the contracted state between the time when the puncture needle is pulled out and the insertion of the catheter, but the tubular member is made of a relatively rigid material. Thus, the shape of the pressed part is maintained. In particular, the sheath having the above configuration can be prevented from being greatly reduced in diameter as compared with a case where only a soft elastic member is formed, for example, and is not blocked. At the same time, when the catheter is inserted, it can be deformed into an expanded state in which a cut is opened while the soft elastic member is extended in accordance with the thickness of the catheter. As a result, the catheter can be inserted while maintaining a state in which the burden on the patient is reduced at the time of sheath piercing.

In the present invention, when the tubular member has one cut and a C-shaped cross section, the above characteristics can be obtained while securing the inner diameter as much as possible by arranging a soft elastic member corresponding to the cut portion.
In addition, when using a tubular member coated with a hard elastic coating so as to leave a part of the periphery of the cylindrical soft elastic member, that is, when the area where the soft elastic member is disposed is not only the cut portion of the tubular member Since a sheath formed of a tubular member and a soft elastic member can be obtained without using an adhesive or the like, the manufacturing cost and the like can be suppressed while having the above effects.

In addition, when using a sheath in which a soft elastic member is disposed in a state of being tightly fitted to the inner peripheral surface of a tubular part having a C-shaped cross section, the catheter slides along the soft elastic member; Thus, the catheter can be inserted more easily than when inserted along the hard elastic coating.
Further, since a part of the peripheral portion of the tubular member is thinned, even when a relatively high-rigidity material is used for the tubular member, when the diameter is reduced, the tubular member is bent around the thin portion, The inner peripheral surface can be adapted to the shape of the puncture needle. Moreover, it has the effect which can adapt also to the shape of a catheter by extending | stretching centering on the said thin part. In particular, the thin-walled portion has a shape in which a semi-elliptical cutout portion is provided, and particularly when there are a plurality of the semi-elliptical shapes, the stress relating to the thin-walled portion is dispersed, and the cutout portion It is possible to prevent the occurrence of cracks.

  When the sheath body is configured such that the elastic plate material is wound in a spiral shape, the diameter of the sheath body can be expanded and contracted by sliding the elastic plate material in the circumferential direction, and a gap is generated in the sheath body. There is no. In addition, when the diameter is reduced by being wound, a plurality of elastic plate members are laminated in the radial direction, so that durability against a pressing force from the outside is improved as compared with the case of a single layer. Therefore, similarly to the above effect, the catheter can be inserted while maintaining the reduced diameter state at the time of sheath piercing. In particular, at this time, if the sheath body is set to be in a reduced diameter state or a state close thereto without external force acting, the burden on the patient during sheath puncture can be easily reduced and necessary. It is preferable because the diameter of the sheath at the time can be easily realized.

  As described above, it is possible to provide a catheter insertion sheath that allows a catheter to be easily inserted while maintaining a reduced diameter state of the sheath set so as to reduce the burden on the patient during sheath piercing.

A sheath for catheter insertion according to an embodiment of the present invention will be described with reference to the drawings.
(Example 1)
(overall structure)
First, an outline of a catheter insertion sheath in the present embodiment will be described with reference to FIG. FIG. 1 (a) is a schematic diagram of the sheath 10 and the puncture needle 20, and FIG. 1 (b) is a schematic diagram of the state where the puncture needle 20 is inserted into the sheath 10. FIG.

  The sheath 10 is formed by joining a tube-shaped tube main body portion 11 and a disk-shaped flat plate portion 12 in a state where the respective central axes coincide with each other. The sheath 10 is configured to have a hollow region (hereinafter referred to as “introduction region”) 100 in a state of penetrating in the Z direction, that is, a puncture needle 20 described later. As shown in an enlarged XZ sectional view of the portion P10, the sheath 10 has an inner diameter R10 and a tube thickness D10. The tube main body 11 extends in the axial direction (Z direction), and the configuration is such that the tubular member 30 having the cut 13 extending along the axial direction and the cut 13 are bridged. The soft elastic member 40 is arranged so as to be. The cut 13 has a length L1a (≦ L1) as illustrated along the axial direction. The cross-sectional shape (A-A cross section) of the tube main body 11 of the sheath 10 made of these members is as described later. The sheath 10 is provided with a tear line (not shown) for tearing the sheath 10 from the flat plate 10 to the distal end portion of the tube main body 11.

  The piercing needle 20 has a thin needle-like body 21 extending in the Z direction, and a thin disc-shaped restraining portion 22 and a cylindrical handle 23 in the vicinity of one end of the needle-like body 21 so that their central axes coincide with each other. It is joined with. The needle-like body 21 and the restraining portion 22 are made of, for example, stainless steel, and the outer diameter R20 shown in the enlarged view of the XZ section of a part P20 of the needle-like body 21 is smaller than the inner diameter R10 of the sheath 10. Further, the length L2 of the needle-like body 21 is longer than the length L1 of the sheath 10. Note that, unlike the end where the handle 23 is joined to the needle-like body 21, the other end is pointed.

As shown in FIG. 1 (b), the combination of the sheath 10 and the puncture needle 20 is such that the puncture needle 20 is inserted into the sheath 10, the restraining portion 22 is in contact with the flat plate portion 12, and the above-described cusps of the needle-like body 21 are used. In this state, the shape portion protrudes from the tube main body portion 11.
(About the cross section of sheath 10)
Next, a cross-sectional shape perpendicular to the axial direction of the sheath 10 will be described with reference to FIG. FIG. 2 is a schematic diagram showing the AA cross section of FIG. 2A is a cross-sectional view of the sheath 10, and FIG. 2B is a cross-sectional view in which the cross-sectional area of the sheath 10 is enlarged.

  As shown in the figure, the sheath 10 according to the present embodiment has a configuration in which a tubular member 30 and a soft elastic member 40 are connected in the circumferential direction, and an introduction space 100 is provided in a substantially central portion. The introduction space 100 is inserted with a puncture needle 20 and a later-described catheter. Both the tubular member 30 and the soft elastic member 40 have a shape with C1 as the central axis position. Although the tubular member 30 is formed of a material having rigidity, a certain degree of flexibility is necessary so that the tubular member 30 can be deformed. The soft elastic member 40 is made of a soft elastic material with respect to the tubular member 30. That is, the soft elastic member 40 is set so as to easily expand and contract under pressure as compared with the tubular member 30. The connection between the tubular member 30 and the soft elastic member 40 is joined, but it may be by adhesion or fitting or by other methods.

  The tubular member 30 is made of, for example, polystyrene, and the member thickness is 0.1 to 3.0 mm. The tubular member 30 has a cut 13 extending along the axial direction (see FIG. 1), that is, a part in the circumferential direction is cut away, and the cross-sectional shape seen from the axial direction is shown in FIG. It has a C shape. The diameter R101 on the inner peripheral side of the cross section is 1.0 to 7.0 mm, and has end faces 30a and 30b. The tubular member 30 has a semi-elliptical groove (hereinafter referred to as “inner” in the inner circumferential surface of the tubular member 30 in the A portion which is a position (circumferential center portion) opposite to the notched region and the center C1. 5) 311 are provided, and 5 semi-elliptical grooves (hereinafter referred to as “outer grooves”) 312 are provided on the outer peripheral surface. Has been processed. When the inner groove 311 has a width W11 and the outer groove 312 has a width W12 as shown in the enlarged view of part A of FIG. The interval between the 30 end faces 30a and 30b (angle α from the center C1) is smaller than when the thinned portion is not bent, so that the inner diameter R101 and the outer diameter R20 of the puncture needle 20 are substantially equal. Is set. The inner grooves 311 and the outer grooves 312 are preferably formed at positions where they face each other, but they may not be opposed to each other, and may be formed at positions opposite to the cuts 13. It may be another part. In addition, the number may be 5 or more, but the number of each provided more than one, the stress for bending and stretching is distributed to the thin-walled processed portion, and the thin-walled portion is cracked. This is preferable because of the effect of preventing the occurrence of the above. Further, both the inner groove 311 and the outer groove 312 may not be provided, and only one of them may be provided. However, in that case, it is assumed that the position, number, or size is such that the tubular member 30 is not broken even when the widths W11, W12 of the inner groove 311 and the outer groove 312 are increased. Further, the cut 13 included in the tubular member 30 is not limited to one but may be two or more, that is, the section of the tubular member 30 viewed from the axial direction may not be C-shaped. However, the cross section seen from the axial direction is substantially ring-shaped, and has elasticity that does not change its shape extremely even if it receives pressure from the stomach wall or abdominal wall when the sheath 10 is pierced It will be necessary.

  The soft elastic member 40 is arranged so as to bridge the cut 13 portion of the tubular member 30, and is softer than the tubular member 30, for example, an elastic body made of polystyrene. The member thickness is 0.1 to 3.0 mm. is there. The soft elastic member 40 has a band shape, but its width is set so as to be disposed in a notched region of the tubular member 30. When arranged as described above, the cross section of the tube main body 11 is connected to the tubular member 30 as shown in FIG. At this time, the inner peripheral diameter formed by the soft elastic member 40 is slightly larger than the inner peripheral diameter R10 of the tubular member 30.

  In the cross section of the tube main body 11 to which the members 30 and 40 are connected, the thinned portion is expanded, and the width of the inner groove 311 is increased (W111) as shown in the enlarged view of part A in FIG. > W11) and the width of the outer groove 312 is reduced (W12 <W112), the inner diameter R111 of the sheath 10 is also larger than the minimum inner diameter R111, and the introduction space 100 in the sheath 10 is The occupied area is also larger than the introduction space in FIG.

As for the connecting portion between the tubular member 30 and the soft elastic member 40, a part of each is overlapped, and, for example, joined at a portion coinciding with the boundary line l1 as shown in the enlarged end view. That is, the tubular member 30 has flat end surfaces 30a and 30b, and the soft elastic member 40 also has flat end surfaces 40a and 40b, and these end surfaces are joined to each other. Further, as shown in the enlarged view of the S portion, the end surface 30a, 30b positioned in the tubular member 30 is recessed to the position of the boundary line l2 in a state of being embedded in the tubular member 30 rather than the boundary line l1. A soft elastic member 40 having a flat end surface or a protruding end surface is inserted and combined up to the position of the boundary line l2, or each uneven surface of the end surfaces 30a and 30b. May be combined in the opposite configuration.
(About catheter construction procedure)
Next, a procedure for constructing a gastric fistula catheter using the sheath 10 having the above configuration will be described with reference to FIG. FIG. 3 is a schematic sectional view showing a procedure for constructing a gastric fistula catheter.

  The stomach 10 (FIG. 3 (a)) in contact with the abdominal wall 50 is pierced with the sheath 10 into which the puncture needle 20 is inserted in the direction of the arrow, and the puncture needle 20 and the distal end of the sheath 10 are inside the stomach. The state reaches 61 (Fig. 3 (b)). During the puncture, the sheath cross-sectional area is as small as possible, that is, the inner diameter of the sheath 10 is minimized (R101 = R20) (see FIG. 2 (a)), and catheter insertion described later is performed. The size is such that the insertion is possible.

  Next, as shown in FIG. 3 (c), while keeping the sheath 10 penetrating the abdominal wall 50 and the stomach wall 60, only the puncture needle 20 is pulled out in the direction of the arrow. Thereafter, the catheter 70 is inserted into the stomach interior 61 by introducing the catheter 70 into the introduction space 100 of the sheath 10 as shown in FIG. When this catheter 70 is inserted, the cut 13 is closed (the end faces 30a and 30b are in contact), and the soft elastic member 40 is stretched to open the cut 13 and the outer groove 312 Since the width is reduced and the width of the inner groove 311 is increased, the interval between the end faces 30a and 30b of the tubular member 30 is increased, and as a result, the inner diameter of the sheath 10 is increased.

Then, the flat plate portion 12 is gripped and pulled in the direction of the arrow, the sheath 10 is torn away from the catheter 70, and further, torn along the tear line (not shown) in the axial direction of the sheath 10 (FIG. 3). (e)). Thereafter, the sheath 10 is withdrawn from the body to form a state in which only the catheter 70 penetrates the stomach interior 61 through the abdominal wall 50 and the stomach wall 60 as shown in FIG. 3 (f).
It should be noted that when the catheter 70 is inserted as shown in FIG. 3 (d), it is desirable to insert it as follows, although it depends on the rigidity of the catheter 70 and the sheath 10, and will be described with reference to FIG. FIG. 4 is a schematic diagram showing a catheter insertion step when the method is employed.

  First, as shown in FIG. 4 (b), the catheter guide 71 is curved as shown in FIG. 4 (b) with respect to the catheter guide 71 having a U-shaped cross section as shown in FIG. The catheter 70 is placed along the part. At this time, a lubricant such as silicone or petrolatum is disposed on the inner peripheral surface of the curved portion. The catheter guide 71 is made of PP, PE, or the like, and has higher rigidity than the catheter 70. As for the shape, one end in the extending direction (X direction) has a substantially pointed shape as shown in the figure. By having a substantially pointed shape protruding in this manner, even if the open end of the catheter 70 is reduced or closed, the catheter guide 71 can be easily guided into the open end, and the catheter 70 Will help to insert.

Next, with the catheter 70 placed, the catheter guide 71 is advanced in the insertion direction (see FIG. 4B) and inserted into the sheath 10. At this time, the lubricant is applied to the surface. Then, after inserting the cartel guide 71, only the catheter guide 71 is pulled out from the sheath 10, and only the catheter 70 is inserted into the sheath (see FIG. 3 (d)).
By using the above method, the catheter 70 made of a relatively soft elastic material is also inserted together with the catheter guide 71, so that the tube portion can be smoothly inserted into the sheath 10 without being bent during insertion. Can do. The shape of the catheter guide 71 is not limited to a U-shaped cross section as shown in the figure, and a cylindrical shape or other shapes greatly affects the expansion of the inner diameter of the sheath 10. It doesn't matter if it doesn't. Further, the removal of the catheter guide 71 from the sheath 10 is not limited to the extraction method as described above. For example, the catheter guide 71 is attached to the catheter guide 71 in the same manner as when the sheath 10 is extracted from the stomach interior 61. A method may be employed in which a tear line is provided and the catheter guide 71 and the sheath 10 are sequentially pulled out including the tearing step or are pulled out at the same time. The above-mentioned lubricant may not be used, but it is as described above in order to smoothly perform each step when the catheter guide 71 is inserted into the sheath 10 and when the catheter guide 71 is pulled out from the sheath 10. It is preferable to use it.
(Effects in this example)
The effects obtained when constructing the gastric fistula catheter 70 using the sheath 10 in the present embodiment will be described in detail.

  The puncture of the sheath 10 can be performed in a state where the diameter is reduced so as to close the cut 13 portion of the tubular member 30 in accordance with the shape of the puncture needle 20. Further, immediately after the puncture needle 20 is pulled out as shown in FIG. 3 (c), the inner diameter of the sheath 10 substantially matches the outer diameter R20 of the puncture needle 20, and the catheter can be easily inserted. Is set. After that, until the insertion of the catheter 70, the pressed portion in the sheath 10 receives a pressing force that reduces the diameter due to the recovery force of the abdominal wall 50 and the stomach wall 60. In the case where the member is formed only with such a member having a large expansion / contraction function, there is a concern that the diameter is greatly reduced and further, the member is blocked. However, in this embodiment, since the tubular member 30 has rigidity, even if the pressing force is applied after the puncture needle 20 is pulled out, the inner diameter and shape of the pressed portion are maintained, and reduction and blocking are prevented. can do. Even if the catheter 70 is thicker than the inner diameter of the sheath 10 that is maintained, the elastic characteristics of the soft elastic member 40 can be utilized by applying a slight force so as to expand the pressed portion. Thus, the thickness of the catheter 70 can be adapted. In particular, it is possible to avoid a situation in which the pressed part is blocked, so that it is not necessary to apply a large force to secure the inner diameter necessary for inserting the catheter again. Therefore, the inner diameter of the sheath 10 that allows the catheter 70 to be inserted can be secured by applying a slight force. Further, by extending the thin portion so that the width of the inner groove 311 of the tubular member 30 is increased and the width of the outer groove 312 is decreased, the introduction space 100 of the sheath 10 is further expanded. Yes.

By utilizing the above feature, when inserting the catheter 70 into the stomach interior 61 through the sheath 10, it is not necessary to apply a new force to the sheath 10 that increases the burden on the patient.
In addition, the tubular member 30 used in the configuration of the sheath 10 has a cut 13 extending along the axial direction, but the soft elastic member 40 is bridged, so that the sheath 13 is cut from the cut 13 portion. A part of the abdominal wall 50 and stomach wall 60 does not enter the interior (introduction space 100), and foreign substances do not enter. Further, when the sheath 10 is pierced and inserted into the body, it is possible to prevent the shape of the pressed portion in the sheath 10 from being deformed by receiving a pressing force on the cut 13 portion.

Further, since the soft elastic member 40 is softer than the tubular member 30, it is possible to deform the soft elastic member 40 into an expanded state in which the cut 13 portion is opened while being extended.
As described above, since the sheath 10 is configured by the tubular member 30 and the soft elastic member 40 at least in a cross section at a position corresponding to the insertion range into the body, when the sheath 10 is inserted into the stomach interior 61, The formed reduced diameter state can be maintained until the catheter 70 is inserted. This makes it possible to insert the catheter 70 into the stomach interior 61 and to construct a gastric fistula catheter without giving a new burden to the patient while keeping the sheath pierced in a state where the burden is reduced. .

It should be noted that the component part composed of the tubular member 30 and the soft elastic member 40 in this way corresponds to the body insertion range, particularly the abdominal wall 50 and the stomach wall 60, of the tube main body 11 when the sheath 10 is pierced. It is preferable to be formed in a range corresponding to the position where it is to be applied, but even if it is formed over the entire range in the axial direction, it can be applied because the same effect can be obtained. At this time, it is preferable that the inner diameter and the shape of the sheath 10 are secured at the end where the puncture needle 20 and the catheter 70 are inserted as in the case of the pressed part.
(Example 2)
Next, a sheath 10a including a tube main body 11a having a configuration different from that of (Example 1) will be described with reference to FIG. FIG. 5 is a cross-sectional view of the tube body 11a of the sheath 10a in the present embodiment. In the present embodiment, only the above-described components are different from those in (Embodiment 1), and description of other portions is omitted.
(About the cross section of the sheath 10a)
The sheath 10a has a constituent part formed by combining a tubular member 301 and a soft elastic member 401 as shown in FIG. 5 (a). This configuration range exists in the same range as in (Example 1). The configuration is such that a soft elastic member 401 having a substantially ring shape is coated with a tubular member 301. Here, the soft elastic member 401 is made of a soft elastic body rather than the tubular member 301 as in the first embodiment.

  The tubular member 301 has a cylindrical shape formed by injection molding or the like. This tubular member 301 is also provided with a cut 13 portion extending along the axial direction, and when viewed from the axial direction, the cross section is a C shape with a part cut in the circumferential direction, and two end faces 301a, This is a configuration having 301b. These two end surfaces 301a and 301b are formed in a contactable state as shown in FIG. 5 (a). The tubular member 301 is set so that the inner diameter R102 in the state of FIG. 5 (a) is substantially equal to the outer diameter R20 of the puncture needle 20. The end surfaces 301a and 301b are provided with a substantially circular opening at the center so as to penetrate each other. Further, as in (Example 1), the inner groove 321 on the inner peripheral surface and the outer groove 322 on the outer peripheral surface have a semi-elliptical shape in and near the B portion where the cross sections 301a and 301b contact each other. The thin-walled processing is performed in a state where five pieces are formed in each state. Note that the shapes of the cross sections 301a and 301b may be smooth surfaces or may be in a state where the surfaces are fitted to each other.

The soft elastic member 401 also has a cylindrical shape, is inserted through a hollow region in a penetrating state provided in the tubular member 301, and has a substantially circular shape when viewed from the axial direction. Note that the soft elastic member 401 is exposed at a portion corresponding to the cut of the tubular member 301.
In the sheath 10a of the present embodiment, the tubular member 301 is covered except for a part of the soft elastic member 401. Therefore, the relative position of the tubular member 301 with respect to the soft elastic member 401 is not necessarily fixed. Absent. For example, the tubular member 301 and the soft elastic member 401 may be in a state where the tubular member 301 slides on the soft elastic member 401 only by being covered without using an adhesive or the like.
(Effects in this example)
Also in this embodiment, the tubular member 301 maintains the reduced diameter state formed at the time of puncture of the sheath 10a after the sheath 10a is pierced into the stomach interior 61 and before the catheter 70 is inserted. Can do.

  Since the sheath 10a is in the thinnest state with the inner diameter of the sheath 10a being substantially equal to the outer diameter of the puncture needle 20, the cross-section of the pressure-receiving portion until the catheter 70 is inserted after the sheath 10a is pierced The shape, the inner diameter, and the outer diameter maintain the minimum state. If the case where the inner diameter of the sheath 10a is equal to the outer diameter R20 of the piercing needle 20 is not the minimum, the sheath 10a is subjected to a pressing force after piercing the sheath 10a and withdrawing the piercing needle 20, Even if the pressure-receiving portion is reduced in diameter, the size of the pressure-receiving portion contracts only within a certain range. The predetermined range is a state in which the end surfaces 301a and 301b are in contact with each other and the width of the inner groove 321 is minimized, and the size of the introduction space 100a is secured. Therefore, it is possible to avoid a situation in which the pressed portion in the sheath 10a is greatly reduced in diameter, and even to be blocked, so that the inner diameter of the sheath 10b adapted to the outer diameter R20 of the catheter 70 can be formed by applying a slight force. Is possible. Thereby, it is possible to easily insert the catheter 70 as in (Example 1).

From the above, it is possible to maintain the sheath 10a in a reduced diameter state in which the burden on the patient is reduced when the sheath 10a is pierced until the catheter 70 is inserted. Furthermore, even if it is necessary to increase the diameter of the catheter insertion port in the sheath or the sheath to cope with the outer diameter R20 of the catheter 70, a slight force is applied to the portion maintained by the tubular member 301. It can be enlarged just by adding. As a result, it is effective because a new burden is not imposed on the patient when the catheter 70 is inserted. In addition, when it is set as the structure which does not use an adhesive agent etc. for the connection of the tubular member 301 and the soft elastic member 401, there also exists an effect which suppresses the manufacturing cost of the sheath 10a.
(Example 3)
Next, a sheath 10b having a configuration different from that of (Example 1) and (Example 2) will be described with reference to FIG. FIG. 6 is a cross-sectional view of the sheath 10b in the present embodiment. In the present embodiment, only the above-described components are different from those in (Embodiment 1) and (Embodiment 2), and description of other portions is omitted.
(About the cross section of the sheath 10b)
As shown in FIG. 6 (a), the sheath 10b in this embodiment has a configuration in which a soft elastic member 402 is tightly fitted in a state along the inner peripheral surface of a tubular member 302 that is a tubular member when viewed from the axial direction. I am doing. Also in this embodiment, the soft elastic member 402 is made of a soft elastic body rather than the tubular member 302. The existence range of the above configuration is the same as in (Example 1) and (Example 2).

  The tubular member 302 has a cylindrical shape, has a cut 13 extending along the axial direction, is a C shape with a part cut in the circumferential direction when viewed from the axial direction, and has two end faces 302a and 302b. Have. The end surfaces 302a and 302b have surface shapes that can contact each other, and may be flat surfaces or surface shapes that fit each other. In addition, as in (Example 1) and (Example 2), the inner groove 331 on the inner peripheral surface and the outer groove on the outer peripheral surface are located in the C portion where the end surfaces 302a and 302b are in contact with each other and in the vicinity thereof. 332 is a semi-elliptical shape, each provided with 5 pieces and thin-walled.

The soft elastic member 402 has a cylindrical shape, and is tightly fitted in a state of being arranged so as to bridge the inner periphery of the tubular member 302 and the cut 13 included in the tubular member 302. Further, the inner diameter R103 of the soft elastic member 402 is such that the inner groove 331 has a reduced width and the outer groove 332 has a larger width as shown in FIG. , 302b is in contact with the outer diameter R20 of the puncture needle 20.
(Effects in this example)
Also in this embodiment, the pressed portion can maintain its shape even after receiving a pressing force from the abdominal wall 50, the stomach wall 60, or the like after the sheath 10b is pierced until the catheter is inserted. . Further, even if the outer diameter R20 of the puncture needle 20 is larger than that in the state of FIG. 6 (a), after the puncture needle 20 is pulled out, the diameter of the pressed portion may be slightly reduced. However, at least the size shown in FIG. 6 (a) can be secured. Thereby, the inner diameter required for insertion of the catheter 70 can be ensured by applying a slight force.

In particular, the sheath 10b of the present embodiment has a configuration in which the inner peripheral surface is formed of the soft elastic member 402, and thus the configuration of the sheath 10b when the inner diameter is smaller than the outer diameter of the catheter. The sheath 10b has an effect of facilitating insertion of the catheter more than in the case of (Example 1) and (Example 2).
As described above, since the catheter 70 can be easily inserted, the catheter 70 can be inserted into the stomach interior 61 while maintaining the introduction space 100b of the sheath 10b that has been reduced in diameter so as to reduce the burden on the patient. Can do. As a result, when the catheter 70 is inserted after piercing the sheaths 10b and 10ba, the catheter 70 can be easily constructed without newly increasing the burden on the patient.

Also in the present embodiment, the range constituted by the tubular member 30 and the soft elastic member 40 is only a portion corresponding to the positions of the abdominal wall 50 and the stomach wall 60, or the entire range in the axial direction of the sheaths 10b and 10ba. In both cases, the same effect can be obtained, so that it is applicable.
(Example 4)
Further, the configuration of the sheath 10c different from the above-described embodiments will be described with reference to FIG. FIG. 7 is a cross-sectional view of the sheath 10c in the present embodiment. Also in this embodiment, since only the cross-sectional shape is different from each embodiment, description of other configurations will be omitted.
(About the cross section of the sheath 10c)
As shown in FIG. 7A, the sheath 10c in the present embodiment has a configuration in which an elastic plate member 403 is wound in a spiral shape as shown in FIG. 7A. The elasticity of the elastic plate member 403 used here is the same as the soft elasticity of the soft elastic members 40, 401, 402 in the above embodiments.

As shown in the drawing, the second winding end 403b is wound so as to enter the inner peripheral side with respect to the first winding end 403a, and the inner diameter R103 in this state is the outer diameter R20 of the puncture needle 20. Is set to be approximately equal. This soft elastic member 403 is, for example, as shown in the enlarged view of the P part, so that the thickness D1100 on the end side in the circumferential direction is smaller than the thickness D1000 on the central side in the circumferential direction. The thickness is reduced as it moves from the end to the end side. However, it is possible to form a smooth outer peripheral surface and inner peripheral surface, such as a wound body having a thickness variation as described above, or to adapt to the shape of the puncture needle 20 or catheter 70 inserted into the introduction space 100c. As long as the inner peripheral surface can be formed, the present embodiment is not limited to those having the above thickness variation, and can be applied to a constant thickness or other thickness variations.
(Effects in this example)
The effects that can be obtained when constructing a gastric fistula catheter using the sheath 10c of the present embodiment will be described.

  First, by winding as shown in FIG. 7 (a), the elastic plate 403 is a soft elastic body, but the elastic plate 403 is laminated in the radial direction. The durability is higher than that of a single layer. Therefore, if the elasticity of the elastic plate 403 is set so as not to cause a large shape change with respect to the pressing force received from the abdominal wall 50, the stomach wall 60, etc., the sheath 10c can be used from the time of puncture to the time of insertion of the catheter 70. In the meantime, it is possible to prevent the pressed portion or the catheter 70 insertion port from being greatly reduced in diameter or blocked.

  Furthermore, when the catheter 70 is inserted, an introduction space 100c adapted to the thickness of the catheter 70 can be formed by the extension function of the elastic plate member 403. In particular, in this embodiment, since the entire sheath 10c is formed of the elastic plate material 403, the expansion rate of the pressure-receiving portion by the sheath 10c is larger than that of the other embodiments. For example, if the sheath 10c in this embodiment is set so as to be in a reduced diameter state (FIG. 7 (a)) or a state close thereto in a state where no external force is applied, the sheath 10c received from the abdominal wall 50, the stomach wall 60, or the like. Durability against the degree of pressure is sufficiently provided, and expansion and contraction can be easily performed. Accordingly, it is possible to sufficiently maintain the reduced diameter state at the time of piercing of the sheath 10c, and to easily realize even if expansion or contraction of the pressed portion or the insertion port of the catheter 70 is required at the time of insertion of the catheter 70, etc. This is preferable.

  Further, as shown in FIG. 7 (b), the inner diameter of the sheath 10c is expanded to a state where the vicinity of each winding end 403a, 403b is in contact with each other, for example, each winding end The inner diameter of the sheath 10c may be increased until the 403a and 403b are separated without contact. However, in that case, in the pressed part, the part of the abdominal wall 50 or stomach wall 60 is prevented from entering from the gap while the shape of the pressed part is maintained to some extent by the part covered with the elastic plate 403. It is desirable to insert quickly.

   As described above, also in the present embodiment, the sheath 10c having a reduced diameter is pierced to reduce the burden on the patient, and the size of the pressed portion formed thereby is maintained until the catheter 70 is inserted. be able to. As a result, it is possible to easily insert the catheter 70 and construct the catheter 70 without forcing a new burden on the patient when the catheter 70 is inserted.

It should be noted that the number of times of wrinkles for forming the spiral shape in the present embodiment is reduced until the catheter 10 is inserted after the sheath 10c is pierced into the stomach 61 in consideration of the elasticity, viscosity, thickness, etc. of the elastic plate 403. As long as the diameter can be maintained and the catheter is inserted and smoothly expanded in accordance with its thickness, it may be performed once or more. Further, in this embodiment, the winding direction is set to be perpendicular to the axial direction, but the same effect can be obtained even if the winding direction is spirally inclined with respect to the axial direction. If so, it is applicable.
(Other matters)
The catheter insertion sheath according to the present embodiment is an example, and not only one and two types of members but also more members may be used as long as similar effects can be obtained. You may utilize the sheath or the sheath which has another winding state.

Further, when forming the thin portion in the tubular members 30, 301, 302, the semi-elliptical cut is not limited to being formed, and other shapes may be provided.
If the soft elastic members 40, 401, 402 and the elastic plate member 403 having elastic characteristics have a mesh structure so as to improve the elastic characteristics, the expansion / contraction effect in the introduction space of the sheath can be further increased. Therefore, it is preferable.

  INDUSTRIAL APPLICABILITY The present invention is effective for realizing a tube insertion and infusion device that can maintain a certain shape even when subjected to external pressure, and that requires an expansion / contraction function that appropriately corresponds to the thickness of the tube to be inserted.

It is a schematic diagram of the sheath with a puncture needle attached state. 1 is a cross-sectional view of a sheath according to Example 1. FIG. It is a schematic diagram which shows the gastrostomy catheter construction procedure which concerns on this embodiment. It is a schematic diagram which shows the process at the time of catheter insertion. 6 is a sectional view of a sheath according to Example 2. FIG. 6 is a sectional view of a sheath according to Example 3. FIG. 6 is a sectional view of a sheath according to Example 4. FIG.

Explanation of symbols

10 sheath
11 Tube body
12 Flat part
20 Puncture needle
21 acicular body
22 Stopping part
23 Handle
30 Tubular member
40 Soft elastic members
50 Abdominal wall
60 stomach wall
61 Inside the stomach
70 catheter
71 Catheter guide
100 introduction space
403 Elastic plate

Claims (10)

A catheter insertion sheath,
A tubular member having at least one cut extending in the axial direction within a range of being inserted into the body;
A member that is softer than the tubular member that bridges the cut; and
Consisting of
A catheter insertion sheath characterized by being deformable from a state in which the tubular member is contracted so as to close the cut, to an expanded state in which the cut is opened while the soft elastic member is extended. The sheath for catheter insertion according to claim 1, wherein the cut is formed at one place, and the tubular member has a C-shaped cross section. The catheter insertion sheath according to claim 2, wherein the tubular member is formed such that a part of a peripheral portion is thin and bends around the thin portion when the diameter is reduced. The catheter insertion sheath according to claim 3, wherein the thin-walled portion is formed with a semi-elliptical cutout. The sheath for catheter insertion according to any one of claims 1 to 4, wherein the soft elastic member has a band shape and is connected in a state of being partially overlapped with an end portion of the tubular member facing the cut. The soft elastic member has a cylindrical shape, and the tubular member has a configuration in which a portion corresponding to a cut in a peripheral part of the cylindrical soft elastic member is left and coated with a hard elastic film. The sheath for catheter insertion in any one of 1-4. The catheter insertion sheath according to any one of claims 1 to 4, wherein the soft elastic member has a cylindrical shape and is closely fitted to an inner periphery of the tubular member. A catheter insertion sheath,
A sheath for catheter insertion, characterized in that the sheath body is formed by winding an elastic plate in a spiral shape, and the diameter of the sheath main body can be expanded or reduced by sliding the elastic plate in the circumferential direction. The sheath for catheter insertion according to claim 8, wherein the sheath body is in a reduced diameter state or a state close thereto in a state where no external force is applied. It is used when inserting a catheter into the catheter insertion sheath according to any one of claims 1 to 9, wherein one end portion has a protruding shape and an inner peripheral surface has a curved shape. And catheter guide.

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