JPH0543390B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a catheter set and a method for using the same, for example, a catheter set comprising a catheter for indwelling in a blood vessel and its accessories, and a method for indwelling a catheter in a blood vessel using the same. It is something.

B. Prior art Conventionally, catheters have been used for purposes such as high-calorie infusion, measurement of blood flow rate and blood pressure in the blood vessels of a living body, and contrast agent injection. There are several ways to use it.

A catheter set is used when inserting such an intravascular indwelling catheter into a predetermined position in a blood vessel, for example, the subclavian vein. For example, when using a catheter set for high-calorie infusion, first inject the anesthetic solution near the catheter insertion point using a thin injection needle of 20 to 23 gauge (outer diameter 0.9 mm to 0.64 mm, inner diameter 0.6 mm to 0.3 mm). The patient is anesthetized, and at the same time, the vein into which the catheter is to be inserted is probed using this injection needle (preliminary puncture). After confirming that venous blood has returned to the syringe barrel, remove the syringe needle.Remember this depth and insert a puncture needle, such as a 14-18 gauge needle with a thick cannula through which the catheter can be inserted, into the same position. Insert (senshibari). (main puncture). Then,
The puncture needle is removed leaving only the cannula, and a catheter is inserted through the indwelling cannula.

However, with these methods, when manually inserting a thick puncture needle, the puncture needle may be mistakenly inserted into the artery and the vein confirmed during the preliminary puncture (the process of probing the veins described above), resulting in a so-called artery puncture. Sometimes I get tired. In such cases, major complications may occur due to bleeding, etc. Moreover, when removing the cannula from the catheter after use, blood will adhere to the surface of the catheter after the cannula is pulled out along the catheter. Some effort is needed.

On the other hand, as a method for eliminating these drawbacks, the so-called Seldinger method, which uses a guide means called a guide wire, is known. In this method, a set of vascular indwelling catheters is used, but since the guide wire 3 used is required to have appropriate physical properties such as elasticity, a coil wound with stainless steel wire 11 as shown in Fig. 13 is used. Alternatively, those coated with a polymer such as Teflon are generally used. The distal end 3a of the coiled guide wire 3 is bent into a J shape as shown in FIG. 14 to prevent damage to blood vessels, and the distal end 3b is rounded by welding. ing.

However, the guide wire 3 described above requires high precision, such as coiling a very thin wire, processing the wire tip into a J shape, and precisely welding the end. is troublesome. Moreover, because it is coiled,
There is a limit to reducing the diameter of the guidewire. If a thin guidewire were to be manufactured, it would be extremely expensive and difficult to use in daily treatments such as insertion of general infusion catheters.

C. Purpose of the Invention The purpose of the present invention is to provide a guide wire that can reliably and safely insert a catheter into a predetermined position, can be manufactured easily and at low cost, and has a small diameter so that the insertion operation can be performed easily and reliably. An object of the present invention is to provide a catheter set and a method for using the same.

D. Structure of the Invention That is, the present invention includes a catheter, a guidewire made of a shape memory alloy, a sheath that is inserted and held in a removable manner to maintain the guidewire in a sterile state, and a distal end portion of the sheath that can be inserted. This relates to a catheter set in which an injection needle having a needle base and a syringe barrel are housed in a container.

Further, in the use of this catheter set, the present invention provides that after the injection needle is inserted into a predetermined location and a predetermined drug solution is injected, the sheath is inserted into the needle base while the injection needle remains in place. Introducing the guidewire into the predetermined location through the interior of the injection needle while removing it from the sheath, then removing the injection needle and introducing the guidewire into the predetermined location while covering the guidewire with the catheter; A method of using the catheter set is also provided, in which the guide wire is then removed.

Example Examples of the present invention will be described below.

1 to 8 show a first embodiment.

The catheter set 30 according to this embodiment has a first
As shown in the figure, a catheter 35 for intravascular placement
(for example, diameter 16 gauge, length 30 cm), a guide wire 23 made of shape memory alloy (for example, diameter 0.84 mm, length 50 cm), a sheath 31 made of polyethylene, for example, through which this guide wire is inserted and held, and guide wire 23 It consists of a syringe needle 32 or an anesthesia/prepuncture needle 32 (for example, diameter 22 gauge, length 7 cm) that can be inserted through it, and a syringe barrel 34 with a capacity of, for example, 5 c.c., into which a needle base 33 with this syringe needle 32 is attached. There is. Each component of this catheter set 30 is housed in a container 40 and handled as a single unit. Further, the front surface side may be covered with a suitable lid. Sheath 31 is used to facilitate aseptic handling of guidewire 23. As mentioned above, each device is stored in a container as a set, making it convenient to use. In other words, you can prepare a sheathed guide wire, injection needle, and syringe barrel that match the size of the catheter, so you can select a catheter of a predetermined size from among various sizes of catheters, and then use the selected catheter size. This saves you the trouble of selecting a suitable guide wire or syringe.

The needle base 33 is connected to the needle 32 as shown in FIG. 2A.
It has an inner surface 37 that forms a continuous surface with respect to the inner passage 36 of the inner surface 37 of the inner surface 37 of the inner surface 36 of the inner surface 36 of the inner surface 36 of the inner surface 36 of the inner surface 36 of the inner surface 36 of the inner surface 36 of FIG. Therefore, this needle base 3
3 is completely different from the normal needle base 13 shown in FIG. 2B, in which the needle 12 is provided protruding into the inner surface 17. For this reason, as shown in Fig. 3, the needle base 3
Insert the guide wire 2 with the sheath 31 placed inside the guide wire 3.
3, and then pass the guide wire 23 through passage 3.
6 can be inserted smoothly. This has a very important meaning as will be explained later.

In addition, the above catheter insertion guide wire 2
3 is extremely distinctive in that it is made of a thin linear shape memory alloy, rather than a coil shape like conventional products.

That is, the shape memory alloy that constitutes this guide wire 23 is mainly composed of titanium and nickel, and its transformation point (point A) is below 37°C, in other words, below normal body temperature. , and the wire is made of a single wire with a wire diameter of 0.05 mmφ to 2.0 mmφ.

Therefore, if this guide wire 23 is used, there is no need for complicated processes such as coil winding of a thin wire or precision welding of the tip as in the conventional method, and the wire diameter of the guide wire is that a single wire is drawn out in a linear shape. This can be reduced to the limit value for (drawing), and extremely thin guidewires can be freely produced. Therefore, it can be easily inserted into a living body. Moreover, the shape of the tip (terminus) 23b does not require any rounding process because the cut part melts and becomes naturally round when it is melted or cut with a laser beam 20 or the like as shown in FIG. ,
Does not require precision machining. Furthermore, this shape memory alloy has been subjected to shape memory treatment so that the tip 23a deforms into the solid line shape (J shape) shown in FIG. 5 at the transformation point. When inserted into the body (as shown in Figure 8B), it has a straight shape before insertion, making it easy to insert through the needle 1 (see Figure 8B), and after insertion into the blood vessel, it has the above-mentioned memorized shape (J shape). The catheter (indicated by a phantom line 35 in FIG. 5) can be smoothly guided to a predetermined position without twisting and damaging the blood vessel.

The diameter of the guide wire 23 can be made as thin as 0.05 mmφ to 2.0 mmφ (for example, 0.84 mmφ and the length is 50 cm), but if it is too thin and becomes less than 0.5 mmφ, the mechanical strength is low and it cannot be used as a guide wire. 2.0mmφ may not be able to fulfill its role.
If it exceeds this point, it may become so hard that it cannot be inserted into a living body.

Furthermore, a noteworthy feature of this guide wire 23 is that it exhibits appropriate elasticity even though it is not in a coil shape, which allows it to be easily inserted into blood vessels in various shapes (intravascular). You can do this while having someone follow you. That is, the guide wire 23
The Ti-Ni alloy constituting the is known to exhibit the so-called superelastic effect as shown in Figure 6, and the stress does not change much as shown in A or B over a wide range of strain. It also has a history characteristic of being able to return to its original shape without plastic deformation. Therefore, elasticity in the bending direction similar to that of conventional coiled guide wires can be achieved using a single wire, and the guide wire can be moved within a blood vessel while easily following a complicated insertion route. Therefore, insertion can be performed with high reliability, and erroneous insertion does not occur. Furthermore, as shown in Figure 8E, when the guidewire is pulled out, the J-shape at the tip easily deforms into a straight line, making it easy to pull out the guidewire. If the following conditions occur, it is possible to return to the linear shape again.

However, if the transformation point (point A) is higher than the body temperature, that is, 37℃ or higher, the above-mentioned superelastic effect will not be exhibited, so point A is preferably set to 37℃ or lower, and 10℃ to 30℃. ℃ is even better. In this A point range,
This makes it possible to take advantage of the unique properties of shape memory alloys, which are flexible at relatively low temperatures (hard at high temperatures). Note that a guide wire with an A point lower than 0° C. can be used, but in clinical practice, the guide wire must be cooled with a refrigerant to keep the A point below or in a straight shape.

Control of the transformation point can be achieved arbitrarily by changing the blending ratio of the main components Ti and Ni, the amount of additives, and the heat treatment conditions. Also, this
In addition to the above properties, Ti-Ni alloys have durability and
It is a desirable material because it has excellent biocompatibility (especially antithrombotic properties). However, this Ti−Ni
Although the alloy may contain other elements such as Cu, Zn, Fe, Al, etc., it is desirable that Ni and Ti account for 95% by weight or more in total.

When using the guidewire according to this example, in addition to the commonly used polymeric materials, the surface of the guidewire must be coated with inert polymers such as Teflon, antithrombotic polymers such as cardiosan, and drugs such as heparin and urokinase. It may also be coated with a polymer or the like that can provide sustained release.

Next, a method of using the catheter set 30 shown above, that is, a method of indwelling the catheter in a blood vessel will be explained.

First, as shown in FIG. 8A, the injection needle 32 is inserted into the living body near the catheter insertion site, and an anesthetic is injected. The puncture position may be near the blood vessel 2 (for example, the subclavian vein). After the anesthetic is injected, the vein into which the catheter is to be inserted is probed using the same needle 32 (corresponding to preliminary puncture), and the backflow of venous blood into the syringe barrel 34 is confirmed.

Next, with the tip of the needle 32 in the vein 2, the syringe barrel 34 is removed from the needle 32, and as shown in FIG. 2 and lead it out into the blood vessel 2 from the inner end. In this case, as described above, the guide wire 23 is inserted into the needle base 33 together with the sheath 31 in FIG. 3, and only the guide wire 23 can be smoothly guided into the blood vessel 2 through the needle 32. In this way, the guide wire 23 is led out into the vein 2 through the needle 32 at the same time as it is removed from the sheath 31, so that sterile conditions are ensured. However, in FIG. 8B, the sheath 31 is omitted for simplicity.

Then, the needle 32 is pulled out in the direction of the arrow 4 in this state, leaving only the guide wire 23 as shown in FIG. 8C.

Next, as shown in FIG. 8D, the guide wire 23
The hollow catheter 35 is inserted into the blood vessel 2 while being twisted as shown by the arrow 6. At this time, the boundary area 7 between the guide wire 23 and the blood vessel 2 is
A scalpel (not shown) is inserted into the catheter 35 to facilitate insertion of the catheter 35.

Next, as shown in FIG. 8E, the catheter 35 is inserted into the blood vessel 2 to a predetermined position as indicated by the arrow 27 while being guided by the guide wire 23. Once in this position, the outer end of catheter 35 may be secured to the vessel surface with surgical thread.

Thereafter, as shown in FIG. 8E, the guide wire 23 is pulled out in the direction of arrow 10, and only the catheter 35 is left in the blood vessel 2 as shown in FIG. 8F. For example, a high-calorie infusion can be injected into the blood vessel using the catheter 35.

As described above, according to the catheter set of this embodiment and its usage method, the needle base 3
Since the inner surface shape of the injection needle 32 has been devised, the injection needle 32 can be continuously inserted into the guide wire 23 after injecting the anesthetic without removing the injection needle 32, as shown in FIG. 8B.
can be inserted. Therefore, there is no risk of accidentally puncturing an artery during the main puncture after the preliminary puncture as in the conventional example described above, and the target artery can always be punctured. can be safely and easily inserted into the Of course, since the operation is performed without using a cannula as in the past, costs can be reduced and problems such as blood adhesion to the catheter surface due to the cannula do not occur.

In addition, the guide wire 23 used is made of a shape memory alloy whose transformation point (A point) is 37°C or less, so the tip has a J shape memorized, for example, but before use, the temperature is lower than the A point. At temperature, it can be returned to a straight line shape by hand. Therefore, insertion into the injection needle 32 becomes extremely easy, and at the same time, when inserted into a blood vessel, the tip momentarily deforms to the original J shape at point A or higher. Therefore, insertion is easy and operation can be performed with high reliability without damaging blood vessels. Furthermore, since the guide wire 23 exhibits the above-mentioned superelastic effect and is a non-coiled solid wire, the wire diameter of the guide wire 23 is small enough to reach the limit value when drawing a solid wire into a linear shape. This means that ultra-thin guidewires can be freely manufactured. Therefore, it can be easily inserted into a living body, and can be manufactured easily and at low cost. In this embodiment, the catheter 35,
Guide wire 23 with sheath 31 and injection needle 3
By effectively combining the two items and storing them in the container 40, there is no need to select them one by one, and the set can be used immediately and quickly in the medical field.

9 to 12 show guide wires 23 of other forms.

The wire shown in FIG. 9 has a thinner tip 23a to make it easier to bend.
In the wire shown in Figure 0, the end 23b is rounded to a larger diameter to more fully prevent blood vessel damage. In addition, the wire in FIG. 11 is wound once at a predetermined location to form a large-diameter portion 23c, and this large-diameter portion is used during insertion (No. 8B
It may be used as a stopper for regulating the position of the process shown in the figure. That is, this can prevent the guide wire from advancing too deeply and damaging the organ of the living body, such as the mitral valve. The one in Figure 12 is the stopper 23c.
This is an example formed by processing.

Further, the memory shape of the wire described above is not limited to the J-shape, but can be any shape such as an S-shape.
The wire itself may also have a shape other than the above-mentioned straight shape.

Although the present invention has been illustrated above, the above-mentioned example can be further modified based on the technical idea of the present invention.

For example, the types, numbers, etc. of the components of the catheter set described above may be varied, and each component may similarly be selected from various shapes and structures. Moreover, the above-mentioned guide wire may take other shapes, and its material may be changed in various ways. Further, the catheter guided by this guide wire can be used not only for infusion but also for other known purposes (blood pressure measurement, contrast medium injection, etc.).

F. Effects of the Invention As described above, the present invention uses a syringe needle through which a guide wire can be inserted as a catheter set, so the guide wire can be continuously inserted without removing the syringe needle after injecting a drug solution. . Therefore, there is no risk of accidentally puncturing another location, and the catheter can always be safely and easily inserted into the desired location. Also,
The guide wire used is made of a shape memory alloy, so the tip has a memorized J shape, for example, and can be returned to a straight shape by hand at a temperature lower than point A (transformation point) before use. This makes it extremely easy to insert the needle into the injection needle, and at the same time, when inserted into the blood vessel, the tip momentarily deforms to its original shape beyond point A. Therefore, insertion is easy and operation can be performed with high reliability without damaging the living body. Moreover, since this guide wire can be made into a non-coiled shape, the diameter of the wire can be reduced, and manufacturing can be achieved easily and at low cost.

The present invention also includes a sheath through which the guidewire is inserted and held in a removable manner, so that the guidewire is not only maintained in a sterile state during storage, but also
When in use, it can be inserted into a living organ while being removed from the sheath, ensuring that sterile conditions are maintained during use.

Furthermore, since the present invention includes a catheter, a guide wire, a sheath for inserting and holding the same, an injection needle, and a syringe barrel as a set, it is convenient to use and medical procedures can be performed quickly.

[Brief explanation of the drawing]

1 to 12 show embodiments of the present invention, in which FIG. 1 is a perspective view of a catheter set;
Fig. 2A is a front view of the injection needle, Fig. 2B is a front view of a conventional injection needle shown for comparison, Fig. 3 is a sectional view showing how the guide wire is inserted into the injection needle, and Fig. 4 The figure is a front view of the main part of the guidewire, Fig. 5 is a front view of the main part of the guidewire with the tip deformed during use, Fig. 6 is a stress-strain curve diagram of the shape memory alloy, and Fig. 7 is the guidewire fabrication. Front view of time, Figure 8A,
Figure 8B, Figure 8C, Figure 8D, Figure 8E, Figure 8
Figures F are cross-sectional views showing the method for indwelling a catheter in a blood vessel in order of main steps;
FIG. 12 is a front view of each main part of another guide wire. 13 and 14 show a conventional example, in which FIG. 13 is a front view of the main part of the guide wire, and FIG. 14 is an enlarged view of the distal end of the guide wire. In addition, in the symbols shown in the drawings, 2... blood vessel,
3, 23... Guide wire, 12, 32... Syringe needle, 13, 33... Needle base, 31... Sheath, 3
4...syringe barrel, 35...catheter, 36...passage, 40...container.

Claims (1)

[Claims] 1. A catheter, a guidewire made of a shape memory alloy, a sheath through which the guidewire is inserted and held in a removable manner to maintain it in a sterile state, and a needle base into which the distal end of the sheath can be inserted. A catheter set includes a syringe needle and a syringe barrel that are housed in a container. 2. A catheter, a guide wire made of a shape memory alloy, a sheath through which the guide wire is inserted and held in a removable manner to maintain it in a sterile state, an injection needle having a needle base into which the distal end of the sheath can be inserted, and an injection needle. When using a catheter set in which a set of tubes and a tube are housed in a container, after the injection needle is stuck into a predetermined location and a predetermined drug solution is injected, the sheath is inserted into the needle while the injection needle remains in place. After inserting into the base, the guidewire is introduced into the predetermined location through the inside of the injection needle while being removed from the sheath, and then the injection needle is removed and the catheter is placed over the guidewire while the guidewire is introduced into the predetermined location. and then the guide wire is pulled out.
How to use the catheter set.