Catheter set and its use

Description: TECHNICAL FIELD [Detailed description of the invention]

B. Industrial application fields The present invention relates to a catheter set and a method of using the same, for example, a catheter set using an intravascular indwelling catheter and its accessories as a set, and a catheter vascular indwelling method using the same. (B) Conventional technology Conventionally, catheters have been used for the purpose of high-calorie infusion, measurement of blood flow rate and blood pressure in blood vessels of a living body, injection of contrast medium, etc., and depending on the purpose, they may be used for long-term indwelling or short-term indwelling. There is a usage. A catheter set is used when inserting such an endovascular indwelling catheter into a blood vessel, for example, a predetermined position in the subclavian vein. For example, when using a catheter set for high-calorie infusion, first inject an anesthetic solution near the catheter insertion position with 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). And anesthetize, and at the same time, use this injection needle to search the vein into which the catheter should be inserted (preliminary puncture). Then, after confirming the return of venous blood to the injection tube, remove the injection needle, and then remember this depth and insert a catheter at the same position, for example, a 14-18 gauge puncture needle with a thick crab. (Injection) is inserted. (Main puncture). Next, the puncture needle is removed leaving only the canyula, and the catheter is further inserted through the indwelling canyula. However, in such a method, when a thick puncture needle is manually inserted, the puncture needle is inserted by mistake for the vein and the artery confirmed in the preliminary puncture (the above-mentioned process of puncturing the vein), and so-called arterial puncture is performed. It may be punctured. In such cases, bleeding and the like may lead to major complications. Moreover, when removing the used canyula from the catheter, blood adheres to the catheter surface after the canyula is pulled out along the catheter. To prevent this, a special cut is made in the canyula to remove it. Ingenuity is required. On the other hand, as a method for eliminating such a defect, a so-called Celdeinger method using a guide means called a guide wire is known. In this method, a set of a catheter for indwelling blood vessels is used, but since physical properties such as appropriate elasticity are required as the guide wire 3 to be used, a coil wound with a stainless steel wire 11 as shown in FIG. Alternatively, a polymer coated with Teflon or the like is generally used. The tip 3a of the coiled guide wire 3 is bent into a J shape as shown in FIG. 14 so as not to damage the blood vessel, and the end 3b thereof is rounded by welding technology. ing. However, in the guide wire 3 as described above, high precision is required and work is required, such as coiling a very thin wire, processing the tip of the wire into a J shape, and precisely welding the end thereof. Is troublesome. Moreover, since it is coiled, there is a limit to reducing the diameter of the guide wire. When it comes to producing a thin guide wire, it becomes very expensive and difficult to use for daily treatment such as insertion of a general infusion catheter. C. Purpose of the invention An object of the present invention is a catheter set provided with a guide wire that can reliably and safely insert a catheter into a predetermined position, can be easily and inexpensively manufactured, has a small diameter, and can be easily and reliably inserted. To provide usage. D. Structure of the invention That is, the present invention has a catheter, a guide wire made of a shape memory alloy, a sheath that allows the guide wire to be pulled out and held in order to keep the guide wire sterile, and a needle base into which the tip of the sheath can be inserted. It relates to a catheter set in which an injection needle and an injection tube are set and housed in a container. Further, in the present invention, in the use of this catheter set, after the injection needle is pierced into a predetermined place to inject a predetermined drug solution, the sheath is inserted into the needle base while the injection needle is left as it is. The guide wire is pulled out from the sheath through the inside of the injection needle and introduced into the inside of the predetermined place, then the injection needle is pulled out and introduced into the inside of the predetermined place while covering the guide wire with the catheter. Next, a method of using a catheter set in which the guide wire is pulled out is also provided. E Example Hereinafter, examples of the present invention will be described. FIGS. 1 to 8 show the first embodiment. As shown in FIG. 1, the catheter set 30 according to this embodiment includes a catheter 35 for intravascular placement (for example, 16 gauge in diameter and 30 cm in length) and a guide wire 23 made of a shape memory alloy (for example, 0.84 mm in diameter). (Length 50 cm), for example, a polyethylene sheath 31 through which this guide wire is inserted and held, an injection needle 32 or an anesthesia / preliminary puncture needle 32 (for example, diameter 22 gauge, length 7 cm) through which the guide wire 23 can be inserted, and this It consists of a syringe barrel 34 with a capacity of, for example, 5 c.c., to which the needle base 33 with the needle 32 is attached. Each part of the catheter set 30 is housed in the container 40 and is treated as one unit. Further, the surface side thereof may be covered with an appropriate lid. The sheath 31 is used to make the guide wire 23 aseptically easy to handle. As described above, each device is stored in a container as a set, which is convenient for use. That is, since a guide wire with a sheath, an injection needle, and a syringe barrel that match the size of the catheter can be prepared, after selecting a catheter of a predetermined size from various sizes of catheters, the size of the selected catheter is adjusted. It is possible to save the trouble of selecting a combined guide wire and syringe. As shown in FIG. 2A, the needle base 33 has an inner surface 37 connected to the internal passage 36 of the needle 32 so as to form a continuous surface. Therefore, the needle base 33 is completely different from the structure in which the needle 12 is projected into the inner surface 17 as in the normal needle base 13 shown in FIG. 2B. Therefore, as shown in FIG. 3, the guide wire 23 can be inserted into the needle base 33 with the sheath 31 covered, and the guide wire 23 can be smoothly inserted into the passage 36 as it is. This has a very important meaning as described later. Further, the catheter insertion guide wire 23 is extremely characteristic in that it is made of a linear thin shape memory alloy instead of a coil shape as in the conventional product. That is, the shape memory alloy constituting the guide wire 23 is mainly composed of titanium and nickel, and its transformation point (point A) is 37 ° C or less, in other words, at normal body temperature or less. It 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, a complicated process such as coil winding of a thin wire or precision welding of the tip is not required as in the conventional case, and a single wire is pulled out linearly as the wire diameter of the guide wire. It can be reduced to the limit value when (drawing), and an ultra-fine guide wire can be freely manufactured. Therefore, it can be easily inserted into the living body. Moreover, the shape of the tip (end) 23b does not require a process for rounding because the cut portion melts and naturally rounds when it is melted or cut with a laser beam 20 or the like as shown in Fig. 7. , Does not require precision processing. Further, this shape memory alloy is shape memory processed so that the tip portion 23a is deformed into the solid line shape (J shape) of FIG. 5 at the transformation point, and therefore, as described later (Fig. 8). When inserting into the body, it has a linear shape before insertion and is easy to insert through needle 1 (see Fig. 8B), and after insertion into the blood vessel, it has the above memory shape (J type). The catheter (shown by virtual line 35 in Fig. 5) can be smoothly guided to a predetermined position without damaging the blood vessel. The diameter of the guide wire 23 can be as thin as 0.05 mmφ to 2.0 mmφ (for example, 0.84 mmφ, length is 50 cm), but if this is too thin and less than 0.5 mmφ, the mechanical strength is small and it can be used as a guide wire. It may not be able to play its role, and if it exceeds 2.0 mmφ, it may become too hard to be inserted into the living body. Furthermore, a notable feature of this guide wire 23 is that it exhibits moderate elasticity even though it is not a coil shape, which makes it easy to insert it into various shapes (intravascular). It can be done while following. That is, the Ti-Ni alloy constituting the guide wire 23 is known to exhibit a so-called superelastic effect as shown in FIG. 6, and the stress is applied to a wide range of strains as in A or B. It has a historical characteristic that it does not change much and can be restored to its original shape without plastic deformation. Therefore, the elasticity in the bending direction similar to that of the conventional coil type guide wire can be realized by a single wire, and even a complicated insertion path can be easily followed and moved in the blood vessel. Therefore, the insertion can be performed with high reliability, and erroneous insertion does not occur. Also, as shown in Fig. 8E, when the guide wire is pulled out, the J shape at the tip is easily deformed into a straight line, so that it can be easily pulled out. If it becomes the following, it can be returned to the linear shape again. However, if the transformation point (point A) is higher than the body temperature of the living body, that is, 37 ° C or higher, the above-mentioned superelastic effect is not exhibited, so the A point should be 37 ° C or lower, which is 10 °. C ~ 30 ° C is even better. In this point A range, it is possible to take advantage of the unique property of shape memory alloys, which is flexible at relatively low temperatures (hardens at high temperatures). Although points A lower than 0 ° C can be used, it is necessary to cool the guide wire with a refrigerant in clinical practice to make it linear with points A or less. The control of the transformation point can be arbitrarily realized by changing the blending ratio of the main components Ti and Ni, the amount of the additive, and the heat treatment conditions. Further, this Ti-Ni alloy is a desirable material because it is excellent in durability and biocompatibility (particularly antithrombotic property) in addition to the above-mentioned properties. However, although this Ti-Ni 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 guide wire according to this example, in addition to the polymer material whose surface is usually used, an inert polymer such as Teflon, an antithrombotic polymer such as cardiosan, and a drug such as heparin and urokinase. May be coated with a polymer or the like capable of sustained release. Next, a method of using the catheter set 30 shown above, that is, a method of intravascular placement of the catheter will be described. First, as shown in FIG. 8A, the injection needle 32 is pierced into the vicinity of the catheter insertion portion of the living body, and the anesthetic is injected. This piercing position may be near blood vessel 2 (eg, subclavian vein). Then, after the injection of this anesthetic, the same needle 32 is used to search the vein into which the catheter should be inserted (corresponding to preliminary puncture), and the regurgitation of venous blood into the injection tube 34 is confirmed. Next, with the tip of the needle 32 inside the vein 2, the injection tube 34 is removed from the needle 32, and as shown in FIG. 8B, the guide wire 23 is of the required length from its base 33 while leaving the needle 32 as it is. Is inserted and led out from the inner end side into the blood vessel 2. In this case, as described above, the guide wire 23 can be 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 as it is. As described above, since the guide wire 23 is led out into the vein 2 through the needle 32 at the same time as the guide wire 23 is removed from the sheath 31, the aseptic state is surely maintained. However, in FIG. 8B, the sheath 31 is not shown for simplification. Then, in that state, the needle 32 is pulled out in the direction of arrow 4, leaving only the guide wire 23 as shown in FIG. 8C. Then, as shown in FIG. 8D, the guide wire 23 is covered with the hollow catheter 35 and inserted into the blood vessel 2 while being twisted as shown by the arrow 6. At this time, a scalpel (not shown) is inserted in advance in the boundary area 7 between the guide wire 23 and the blood vessel 2 so that the catheter 35 can be easily inserted. Subsequently, as shown in FIG. 8E, the catheter 35 is inserted to a predetermined position in the blood vessel 2 as shown by the arrow 27 while being guided by the guide wire 23. At this position, the outer end of the catheter 35 may be secured to the surface of the vessel with a surgical thread. After that, as shown in FIG. 8E, the guide wire 23 is pulled out as shown by arrow 10, and only the catheter 35 is placed in the blood vessel 2 as shown in FIG. 8F. Then, for example, a high-calorie infusion solution can be injected into the blood vessel by the catheter 35. As described above, according to the catheter set of this embodiment and the method of using the catheter set, the inner surface shape of the needle base 33 is devised so that the guide wire 23 can be smoothly passed through the injection needle 32. As shown in the above, the guide wire 23 can be continuously inserted after the injection of the anesthetic without removing the injection needle 32. Therefore, unlike the conventional example described above, there is no risk of accidentally puncturing an artery at the time of main puncture after preliminary puncture, and the target artery can always be punctured, so that the catheter is always in a predetermined position. It is safe and easy to insert. Of course, since the operation is performed without using the canyula as in the conventional case, the cost can be reduced and the problem of blood adhesion to the catheter surface due to the canyula does not occur. Also, since the guide wire 23 to be used is made of a shape memory alloy whose transformation point (point A) is 37 ° C or less, for example, a J shape is stored at the tip, but before use, it is better than point A. At low temperatures, it can be restored to a linear shape by hand. Therefore, it becomes extremely easy to insert it into the injection needle 32, and at the same time, when it is inserted into the blood vessel, it reaches point A or higher and the tip momentarily deforms to the original J shape. Therefore, the insertion is easy and the operation can be performed reliably without damaging the blood vessel. Moreover, since the guide wire 23 exhibits the above-mentioned superelastic effect and is a non-coil-shaped single wire, the wire diameter of the guide wire 23 is small to the limit value when the single wire is drawn linearly (drawn). This makes it possible to freely manufacture ultrafine guide wires. Therefore, it can be easily inserted into a living body, and can be easily manufactured at low cost. In this embodiment, the catheter 35, the guide wire 23 with the sheath 31, and the injection needle 32 are effectively combined and stored in the container 40, so that the work of selecting these one by one is not required and the medical field can be used. It is a set that can be used immediately and quickly. FIGS. 9 to 12 show guide wires 23 in other forms. The wire in FIG. 9 was made easier to bend by making the tip 23a thinner, and the wire in FIG. 10 rounded the end 23b to a larger diameter to better prevent vascular damage. It is a thing. Further, the wire of FIG. 11 may be wound once at a predetermined position to form a large diameter portion 23c, and this large diameter portion may be used as a stopper for position regulation at the time of insertion (step of FIG. 8B). That is, this can prevent the guide wire from advancing too deeply and damaging the organs of the living body such as the mitral valve. The one in FIG. 12 is an example formed by processing Stopper 23c. Further, the storage shape of the wire described above can be any shape such as S shape as well as J shape. The wire itself may also have a shape other than the above-mentioned linear 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 type, number, and the like of the above-mentioned components of the catheter set may be changed in various ways, and each component may be similarly selected in various shapes and structures. Further, the above-mentioned guide wire may have another shape, and the material thereof 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 applications (for blood pressure measurement, contrast medium injection, etc.). F. Action and effect of the invention As described above, since the present invention uses an injection needle through which the guide wire can be inserted as the catheter set, the guide wire can be continuously inserted as it is without pulling out the injection needle after injecting the drug solution. Therefore, there is no risk of accidentally puncturing another part, and the catheter can always be safely and easily inserted at the desired position. Also, since the guide wire used is made of shape memory alloy, for example, the J shape is memorized at the tip, and before use, it can be returned to a straight shape by hand at a temperature lower than point A (transformation point). Therefore, it becomes extremely easy to insert it into the injection needle, and at the same time, when it is inserted into the blood vessel, the tip becomes instantly deformed to the original shape at point A or higher. Therefore, the insertion is easy and the operation can be performed with high reliability without damaging the living body. Moreover, since this guide wire can be made into a non-coil shape, the wire diameter can be reduced, and it can be easily manufactured and realized at low cost. The present invention also includes a sheath that allows the guide wire to be removably inserted and held, so that the guide wire is not only kept sterile during storage, but can also be inserted into a living organ while being removed from the sheath during use. It is also reliable to maintain aseptic condition during use. The present invention further comprises a catheter, a guide wire, and a sheath, an injection needle, and an injection tube for inserting and holding the catheter, so that it is convenient to use and medical practice can be performed quickly.

[Simple explanation of drawings]

1 to 12 show an embodiment of the present invention, FIG. 1 is a perspective view of a catheter set, FIG. 2A is a front view of an injection needle, and FIG. 2B is for comparison. The front view of the conventional injection needle shown, FIG. 3 is a cross-sectional view showing the insertion state of the guide wire into the injection needle, FIG. 4 is a front view of the main part of the guide wire, and FIG. Front view of the main part of the guide wire, Fig. 6 is the stress-strain curve diagram of the shape memory alloy, Fig. 7 is the front view at the time of manufacturing the guide wire, Fig. 8A, Fig. 8B, Fig. 8C, Fig. 8D. , 8E and 8F are cross-sectional views showing the method of intravascular placement of the catheter in the order of the main steps, and FIGS. 9, 10, 11, 11 and 12 are front views of each main part of the other guide wires. Is. FIGS. 13 to 14 show conventional examples, FIG. 13 is a front view of a main part of a guide wire, and FIG. 14 is an enlarged view of a tip portion of a guide wire. In addition, in the code shown in the drawing, 2 ...... blood vessel, 3,23 ...... guide wire, 12,32 ...... injection needle, 13,33 ...... Needle base, 31 ... sheath, 34 ... syringe, 35 ... catheter, 36 ... passage, 40 ... container, is there.