JPH02209159A - Multiple lumen catheter and making thereof - Google Patents

Abstract

PURPOSE: To provide a catheter with lumens which can not only make a blood dialysis but also vein injection easily without piercing a patient's vein by forming three lumens extending from the base end to the opening for the catheter main body, making the section of the third lumen smaller than those of the other two, and receiving a Seldinger wire slidably. CONSTITUTION: The base end of the main body 26 of this catheter is closed at a connector 30 to receive a blood extracting tube 32 and a blood returning tube 34. When the catheter is used, it is inserted into a patient's body so that a blood extracting opening 44 is on the upstream side of a blood returning opening 45, and the opening 45 is on the upstream side of a chip opening 64. When a treatment is carried out, the blood extracting tube 32 and the blood returning tube 34 are connected to a dialyzator, and blood is extracted through an extraction lumen 50, and returned through a returning lumen 52. If a patient needs to be medicated, another lumen 54 can be used. In this way, damages caused by inserting another needle or catheter into the patient's body can be prevented and the patient will not feel uncomfortable.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is directed to a multi-lumen catheter.
lumen catheter), and more particularly to a catheter inserted into a patient's vein for use in hemodialysis (haemodialysis) procedures, and a method of manufacturing such a multi-lumen catheter.

BACKGROUND OF THE INVENTION Multi-lumen catheters have been used for many years for a variety of medical purposes. However, only recently have such catheters been developed for use in hemodialysis. Looking back at the general form of multi-lumen catheters, Pfarre
As far back as 1882, I received U.S. Patent No. 256,590 for such a catheter in the United States.
That means 2018. This patent describes a flexible dual lumen catheter used primarily for cleaning and drainage of the bladder, rectum, stomach and ear, for example. In this type of catheter insertion technique, the catheter is inserted into the orifice of the body without the use of a puncture needle or guide wire.
e) is introduced.

More recently, a catheter was developed by Blake and received US Pat. No. 3,634,924. This patent, granted in 1972, describes a double lumen cardiac balloon catheter that is introduced into a large vein and the balloon is inflated to control flow within the vessel. The catheter can actually be placed by using the balloon as a "sail" to move the blood into or through the heart to where the catheter will perform its intended function. This patent uses two lumens and teaches a method of manufacturing a tip using a plug and a wire that holds the shape of one lumen during the formation of the tip in a molding technique. There is.

Other patents describing commonly used multi-lumen catheters include U.S. Pat.
．． 175.726, 2.819.718, 4,072.146, 4.098.275, 4,134°402, 4,406.656, and No. 4.180.068 can be mentioned.

The surgical cut-down technique of vascular catheters, which has been known to the medical profession for many years, can actually be traced back to the 17th century. However, it was with the introduction of the Seldinger technique, developed around 1953, that new methods of improving vascular use came into use. This technique was used at the Combres of the Northern Conference held in Helsinki in June 1952.
Association, Talent, Medical Radiology 4
(the Congress of the North
ern As5ociat10n of Medica
It is described in a paper that Seldinga presented at a lecture at Rad10logy. This technique uses a hollow needle to first puncture and then insert and place a wire through the needle into the blood vessel.The needle is withdrawn and a catheter is passed over the wire. The skin is inserted and the wire is then withdrawn.

This technique can be used on blood vessels with less potential for trauma, making it an acceptable method for performing many medical procedures.

One of these procedures that has been the subject of considerable research and development is hemodialysis.

Hemodialysis involves temporarily removing blood from a patient in order to extract or separate toxins from the patient's blood.
Hemodialysis, which can be described as a procedure in which purified blood is returned to the same patient, is required for patients with kidney damage. In other words, in hemodialysis, blood is passed through the kidneys (
(particularly to remove moisture).

In cases of chronic kidney failure, hemodialysis must be performed on a recurrent basis, e.g. when kidney transplantation is not possible or is contraindicated for medical reasons.
In late stage kidney disease (tra-indicated), patients will have to undergo dialysis approximately 100 to 150 times per year. This amounts to thousands of accesses to the blood stream, effectively extending dialysis over the rest of the patient's life.

In the late 1960s, Dr. Stanley Chardon (D.
r, 5tanley 5haldon), etc., at the Royal Free Hospital (the Royal Free Hospital, London, UK).
In al), we developed a technique for performing hemodialysis by percutaneously inserting a catheter into deep blood vessels, particularly the femoral artery or vein. This technology is developed by The Lancet (T
he Lancet) October 14, 1961 edition No. 8
It is described in the paper published by Dr. Chardon et al. on pages 57 to 859. Dr. Chardon et al. developed a single-lumen catheter with a tapered tip that is inserted over a Seldinger wire for use in hemodialysis. In addition, Dr. Chardon and others began inserting both inlet and outlet catheters into the femoral vein, a technique that was published in The British Medical Journal on June 19, 1963.
the British Medical Jour -
nal). The insertion of both inlet and outlet catheters into the femoral vein was intended to explore the possibility of a "self-service" approach to dialysis. Dr. Chardon has since successfully performed such a maneuver, allowing the patient to carry and properly manipulate an implanted catheter that is regularly connected to a hemodialysis machine.

As early as 1959, surgical cutdowns were used to insert flexible dual lumen catheters. An example of such a catheter is the McIntoshl catheter, which is published in the journal The American Medical Association.
society10n), February 21, 1959, 13th
It is described on pages 7 to 138. In this publication, a dual lumen catheter is constructed from non-toxic vinyl plastic and is used in the saphenous vein.
It is described that it is inserted into the vena cava by a cut-down technique for the nous vein).

The use of dual lumen catheters in hemodialysis has the advantage that only one vein is affected when blood is dialyzed sequentially. This is because one lumen acts as a conduit for blood flowing from the patient to the dialysis machine, and the other lumen acts as a conduit for blood from the dialysis machine back to the patient. This can be done with traditional systems that require two insertions to place two catheters, as Dr. Chardon did, or with a single catheter that alternates between removing blood and returning purified blood. Unlike traditional systems used with complex dialysis machines, Dr. Chardon's method of placing catheters that are held in place for regular hemodialysis requires additional work to be done elsewhere. had to do it. Dr. Chardon uses the femoral vein, but around 1977, Uldall
Dr. Subclavian (subclavian) held in place
Vian) has started clinical trials for the catheter. A paper describing this was published in October 1979 by Dr. Urdal et al.
ntat10n), Volume 8, No. 10. In addition, Dr. Urdal began experimenting with a coaxial dual lumen catheter for subclavian insertion, which is covered by Canadian Patent No. 1.092.927, issued January 6, 1981. It becomes. Although this particular form of catheter was not a great success on the market, it pioneered dual lumen catheters that were implanted in the subclavian vein for routine hemodialysis.

The next important step in the development of dual-lumen catheters for hemodialysis was described in U.S. Pat. A successful catheter has been provided which is
It overcomes the drawbacks of Urdal's structure.

A later development is described in US Pat. No. 4,451,252, also issued to Martin. This utilizes the well known dual lumen configuration in which the lumens are separated by diametrical partitions and arranged in parallel. The structure disclosed in this patent makes it possible to insert a Seldinger wire through one of the lumens and to obtain a tip that allows this wire to be used as a guide for subcutaneous insertion of a catheter. can.

Structures of this type are disclosed in European Patent Application No. 0079719 to Edelman and in U.S. Pat.
．． No. 619.643, No. 4.583,968, No. 4.568.329, and U.S. Design Patent No. 272.6
It is described in No. 51.

A number of problems have been encountered when manufacturing dual lumen catheters from extrusions in which the lumens are arranged in parallel and separated by a septum. A major problem is that the end or tip of the catheter must be formed with the wire in one lumen by deforming the tip material from one side toward the center of the catheter. As soon as the chip is removed from the mold, the wires are inline.
ne) The wire stores energy when it is displaced laterally toward the center of the chip so that it can return to position and deform the chip away from the center.

Furthermore, since the material forming the chip is obtained by inserting fillers or the like, the cross-sectional shape is asymmetrical, and therefore, when cooled, a shrinkage effect occurs that tends to deform the chip. Because it is desirable to hold the tip concentric with the central axis of the catheter, this drawback is accentuated in products manufactured according to some of the above-mentioned patents.

One method for solving such problems in chip manufacturing is shown in U.S. Pat. No. 4,543,087 to Sommercorn. This patent describes the use of separate molded tips inserted into the extrusion to obtain the necessary flow paths. Although this chip has been a great commercial success, it has the disadvantage that the chip must be inserted into the lumen, thus creating a discontinuous flow path in the return lumen. This is a disadvantage since the blood must meet at the end of the insert and flow through the insert to an opening of smaller cross-section than the lumen itself.

All of the hemodialysis catheters described above have the disadvantage that they cannot easily be used for intravenous administration of fluids. Patients undergoing hemodialysis treatment using a dual-lumen catheter must insert an intravenous needle when this type of medication is required; the catheter not only performs the function of hemodialysis; It is desirable to be able to easily administer intravenous injections without further puncturing the patient's vein.

Accordingly, one of the objects of the invention is to provide such a catheter.

The present invention further improves the catheter tip so that deformation of the catheter tip is substantially prevented and the tip is symmetrical about the axis of the catheter.

The above-mentioned problems with conventional hemodialysis catheters are as follows:
Some are specific to hemodialysis procedures. However, the catheter of the present invention overcomes the shortcomings of prior art renal dialysis catheters and can also have utility in other procedures. Accordingly, although the following discussion herein will be made with respect to hemodialysis, hemodialysis is merely exemplary, and the catheters of the present invention may be used for other procedures.

(Means for Solving the Problems) According to the - aspect of the present invention, the flexible elongated body is provided with a flexible elongated body that extends around an axis in the direction of the potato and has a distal end portion and a proximal end portion that have a tapered tip. , the body defines three lumens extending from the proximal end to respective openings in the body, two of the lumens having a similar cross-sectional shape and an opening disposed in the side of the body. The remaining lumen, the third lumen, extends centrally along the axis of the body between the two lumens along the length of the body and terminates at the tip; A catheter is provided having a cross section smaller than the two lumens and configured to slidably receive a Seldinger wire for insertion.

Another aspect of the invention includes a distal end extending about a longitudinal axis and having a tapered tip, a proximal end, an outer wall, and a septum extending between spaced apart portions on the outer wall. a flexible elongate body having a flexible elongated body having an outer wall and a septum defining first and second lumens extending from a proximal end to a tapered tip, and wherein the outer wall and the septum merge at the tapered tip; the lumen and the outer wall further defines first and second openings to provide fluid communication between the first and second lumens and the exterior of the body, the septum extending along the body from the proximal end; A multi-lumen catheter is provided having a portion defining a third lumen extending axially to the distal end and terminating in a tapered tip within the third opening.

According to another aspect of the invention, a method of manufacturing a multi-lumen catheter having a tapered conical tip and an end opening concentric with the body of the catheter is provided.

The method includes a first lumen extending about a longitudinal axis and extending between a distal end, a proximal end, an outer wall, and spaced apart portions of the outer wall and defining a first lumen and a second lumen, the portion extending in the longitudinal direction. a septum defining a third lumen extending from a proximal end to a distal end with the first and second lumens along an axis of the body; inserting the distal end of the body into a third lumen extending from the distal end; inserting the distal end of the body into a tapered conical mold having an opening centrally disposed to receive the wire; softening the distal end of the body in a mold such that the section deforms into a conical shape and the outer wall of the body merges with the septum to close the first and second lumens; The method is characterized in that it includes a step of forming an opening in the outer wall.

EXAMPLES The invention will now be described with respect to preferred embodiments used in hemodialysis. The drawings and description below are, however, illustrative of the invention and, therefore, the invention is not to be limited by size or characteristic constraints imposed by hemodialysis operations, unless otherwise indicated.

Referring first to FIG. 1, FIG. 1 shows a triple lumen system according to a preferred embodiment of the present invention.
The lun+enl catheter is indicated in its entirety by the reference numeral 20. FIG. 1 also shows, by way of example, a patient undergoing force insertion into the subclavian vein using a Seldinger wire 22. Although catheter 20 is intended for use in hemodialysis procedures, it can of course be inserted into the femoral vein in a similar manner.

The catheter 20 has a wing tab.
24, the device 23 is used to attach a conventional bandage (dre
ssing 122, and the bandage 22 is attached to the patient's skin. As shown in phantom in FIG. 1, the catheter 20 is passed through the bandage, and a flexible elongated generally cylindrical body 26 formed from polyurethane extrusion (extrus 10n) is passed downstream through the skin and further into the clavicle. inserted into the inferior vein. The kachichiru 20 has a conical tip 29 with a tapered tip 28.
have. Regarding the tip, the other end of the main body 30, which will be described in detail later, is a substantially trifurcated branch connector 30, which protrudes outward from the bandage 22 and is fixed by the bandage 22. A cylindrical blood extraction tube 32, a return tube 34, and an intravenous tube (hereinafter also referred to as "intravenous tube") 35 are attached to the trifurcated branch connector 30, which will be described in detail later. do. These tubes are connected to lumens extending through the body 26.

Catheter 20 is shown in more detail in FIG.
Body 26 terminates proximally in connector 30 to receive blood withdrawal tube 32 and return tube 34 . These tubes each have a female luer fitting (136.3) at the outer end.
7 and is adapted to be connected to a corresponding male Luer fitting (not shown) leading to a dialysis machine. These tubes are further provided with a closure clamp (closure claIIp) for selectively closing the tubes.
It carries 38. In FIG. 2, only one clamp is shown.

The IV tube 35 terminates in a rear lock fitting 39 whose outer end receives a syringe or male lock connector.

Wing tabs 24, also known as suture wings, are integrally formed with a central tubular section 40 that allows catheter 20 to rotate relative to knob 24. Main body 2
6 and by means of a shoulder to the end of the connector 30 and a second
held in place by the shoulders. Such rotation is often necessary after insertion of catheter 20 to reorient the intake side opening of tip 28 when it engages the wall of the vein and becomes occluded. The opening will be described in detail later.

As will be described below, the reinforcing portion 42 is blended with the main body 30 over its entire length and has kinks.
The catheter is reinforced to substantially eliminate the possibility of k-ing. Furthermore, the reinforcing portion 42 also serves to seal the puncture site when the catheter is inserted into the patient.

As described below with respect to FIG. 3 and the following figures, tube 35
is aligned with the central lumen so that the Seldinger wire 21 can pass through the catheter. The wire is
It exits at a generally cylindrical tip 29 so that the catheter can be slid over the wire into the patient during insertion. The withdrawal and return tubes 32 and 34 are coupled to the lumen of the body 26 at the connector 30 so as to communicate with the apertures 44, 45 provided near the distal end 28 of the catheter. In FIG. 2 some of these apertures are shown. This allows blood to be taken out and returned in a closed loop with the hemodialysis machine when a catheter is inserted.
This can be done using tubes 32 and 34. Tube 35 can be used for intravenous fluid administration between treatments.

Next, the main body 26, which will be described with reference to FIGS.
and an integral septum 48 extending diametrically across and defining an extraction lumen 50 and a return lumen 52, both lumens being generally C-shaped in cross-section and extending diametrically from a proximal end to a distal end. It extends towards. As clearly shown in FIG. 4, the spherical intermediate portion 53 of the septum 48 projects into the lumens 50 and 52 and extends along the longitudinal axis of the body 26 from the proximal end to the distal end. 54 (hereinafter also referred to as "rIV lumen"). This lumen is an extension of the IV tube 35 and is approximately 0.96 mm (0.038 mm) in this example.
(inch) diameter Seldinger wire.

The extraction lumen 50, with the exception of the tip 29, is occluded by a first insert 56 made of polyurethane and bonded in place using a suitable solvent such as cyclohexanone. A withdrawal opening 44 is provided in the outer wall 46 of the cylindrical portion 26, except in the area of the insert 56, for allowing blood to flow from the patient's vein into the withdrawal lumen 5.
0 to the extraction tube 3 via the connector 30.
2 and the dialysis machine. The aperture 44 is conveniently circular, but may be boat-shaped (s
It can also be made into any suitable shape, including capoid. Additionally, if desired, a void space (
dead 5 paces) can be substantially eliminated.

The return lumen 52 is likewise closed off by a second insert 60 immediately adjacent to the last of several return openings 45 . This last opening is the extraction lumen 5
0 intake apertures 44 closer to the chip than the last of the 0 intake openings 44, the cross flow flow that the returning blood crosses as it finds its way back into the lumen
The risk of (w) is virtually eliminated. Although some cross-flow is not critical, excessive cross-flow will lengthen the time required for dialysis.

As shown in FIGS. 3 and 6, tip 29 is smoothly rounded and gently tapered at end 28 of the catheter to facilitate insertion of catheter 20 into a patient.

As mentioned above, the catheter is adapted for use with Seldinger wires. Thus, the tapered end 29 is aligned with the axis of the body 26 and the venous lumen 5.
Therefore, the centrally disposed IV seal 54 extends to the tip 29 and forms a circular venous opening (hereinafter also referred to as rIV opening) 64. It is terminated.

Catheter 20 is constructed from a long cylindrical polyurethane extrusion forming a cylindrical body 26 . The extrusion is cut to length and the ends are formed by further operations. The formation of the tapered tip 29 will now be described with reference to FIG. 3, as well as the formation of the connector 30.

Before forming the tapered tip, the insert 56
and 60, and the lumens 50 and 5 as shown in FIG.
2 and fix them. The insert is formed in the cross-sectional shape of the lumen and secured as described above. A cylindrical wire 66, shown in dashed lines in FIG. 3 and formed to have a diameter corresponding to that of the guide wire 21 (FIG. 2), is made of tubing material.
), and the tube material is inserted into a conically tapered mold 68, shown in dashed lines. High frequency (
R, F, ), and when it softens, it is pushed into the mold, and the outer wall 46 and the partition wall 48 are merged at the tip 29.The end of the main body has a tapered circular shape. It has a rounded shape, and the material is
Together, the lumens 50 and 52 form the ends 70 and 72. IV sil-
Since the ring 54 is supported by the wire 66, it maintains its shape. The tapered chip is removed from the mold 68 after cooling to some extent, and is further cooled and hardened.

The deformation of the tip thickens the outer wall 46 and septum 48, providing a concentration of material that substantially exceeds the concentration of material in the body of the catheter, thereby strengthening the tip and thus facilitating insertion of the catheter.

Since the wire 66 is not displaced from its normal straight position during the molding operation, no energy is stored in the wire and therefore the wire is not displaced from its normal straight position during the molding operation.
There is no "displacement" of the chip from the desired orientation after being removed from the chip.

Accordingly, openings 44 and 45 are formed in the outer wall 46 of the body 26, such as by cutting out, to allow the wire to be retained inside the chip during cooling. Furthermore, because the extrusion is symmetrical about the wire, the deformed material in the chip moves uniformly to both sides of the central septum. Such collected material at the ends 70,72 of the lumen uniformly cools and contracts, thus preserving the concentricity of the tip about the IV seal 54. Thus, a tapered tip can be successfully formed.

The three-pronged branch connector 30 and the reinforcing portion 42 were formed in 1987.
Applicant's U.S. Patent No. 4゜6, granted July 28,
82.978, the structure of the present invention requires three apertures, whereas two apertures are used in this U.S. patent. . Such modifications can be easily made by adding a third shaped mandrel and following the procedure described in the above-referenced US patent.

In use, as described above, the catheter 20:
facing downstream in the patient's vein, i.e. the extraction opening 4
4 is on the upstream side of the return opening 45, and the opening 45 is on the upstream side of the return opening 45, and the opening 45 is
It is inserted so that it is on the upstream side of the V-chip opening 64.

To proceed with the procedure, withdrawal tube 32 and return tube 34 are connected to a dialysis machine, and the machine withdraws blood through withdrawal lumen 50 and through return lumen 52 in a manner similar to a conventional withdrawal lumen. Between returning and processing the blood, heparin is added to the lumen.
rin) solution to prevent the lumen from filling with clotted blood. However, if the patient requires medication or is required to give blood between procedures, I
A V seal 54 can be used. This results in
This can prevent damage and eliminate discomfort when inserting another needle or catheter into the patient, but it does not interfere with the heparin seal.

When the catheter is not in use, the third lumen can be filled with a relatively small amount of heparin or filled with a cylindrical, solid, flexible patent bar, similar to guidewire 21. rater
You can pack l. This test can eliminate the need for heparin in the third lumen by blocking blood from entering this lumen. Generally, the third lumen has a small cross-section, a regular shape, and no side holes, so it can be more easily kept free of blood.

In addition to these advantages, the centrally located lumen can provide considerable advantages with respect to catheter insertion and removal. Since this lumen has no side holes, a guidewire with an rJJ-shaped end can be used. This is because the guidewire does not exit through the side hole rather than the end opening. In addition, this small lumen can be more easily kept free of clotted blood, and the guide wire can be used to guide catheters with clotted blood within the blood lumen. It can be replaced without being removed. This involves first inserting a Seldinger wire into a catheter in place within a vein, pulling the catheter out along the wire while leaving the wire in place, and then using this wire to guide a new catheter along the wire. This can be done by doing this.

The exemplary catheter that has been described with respect to the drawings does not have the dimensions of a hemodialysis catheter (proport 10n); as noted above, the above description is merely exemplary; therefore, in practice, the catheter is used in the subclavian vein. If so, the dimensions can be as follows: The central lumen is approximately 0.96 mm (0.0
around the central lumen, which may be approximately 1 mm (approximately 0.04 inch) in diameter, to accommodate a Seldinger wire having a diameter of approximately 38 inches) or approximately 0.91 mm (approximately 0.036 inch). The walls forming the bulkhead may have a wall thickness of about 0.25 mm (about 0.010 inch) and merge into an outer wall that has a wall thickness of about 0.33 mm (about 0.013 inch).

The outer diameter of the main body 26 is approximately 3.78 mm (approximately 0.149 inch), and approximately 3.1 m (approximately 0°0048 square inch).
The area available for blood flow in the lumen of can be obtained. In this case, the flow rate would be approximately 237 milliliters per minute, providing an acceptable pressure to flow blood through the lumen.

It is within the scope of the present invention that the catheter can be made in various sizes depending on the application and the configurations described in the claims.

The chip structure shown in FIG. 3 can be made in a variety of ways.Another embodiment of the invention is shown in FIGS. 7 and 8. For ease of understanding, in these figures, members corresponding to those of the above-described embodiments are indicated by the same reference numerals with rlJ prefixed and indicated by two fingers.

Catheter distal end 128 and tip 129 have inserts 156 and 160 that extend to fill unused portions of the extraction and return lumens. The inserts are inserted into the lumens 150, 152 and can be secured therein by a solvent. End 1
28 in the mold 168, the insert 15
6.160 softens and deforms, and the outer wall 146 merges with the septum 148. The tips of inserts 156, 160 also merge with septum 148, as shown in phantom in FIGS. 7 and 8. The catheter thus obtained has a similar appearance to the catheter described above, but has a stiffer tip.

The shape of the insert may vary; for example, it may be thinner at the end near tip 128 to allow the extrusion to be more easily transformed into the shape shown in FIG.

All of the catheters described above feature a septum having a bulbous middle section to accommodate the IV seal. However, the catheter of the present invention is not limited to such a specific cross-sectional shape, and may have a cross-sectional shape as shown in FIG. 9, for example. For ease of understanding, in FIG.
6. The illustrated catheter has a flat-sided septum 248 such that the extraction lumen 250 and the return lumen 252 have a D-shaped cross section.
It is equipped with This thicker septum 248 requires more material to form the catheter and reduces the ratio of the cross-sectional area of the extraction and return lumens to the cross-sectional area of the catheter. However, if this cross-section is advantageous, for example if the external diameter of the catheter is of minor importance, there are many applications and it can be used in veins for hemodialysis.

Referring now to FIG. 10, a molded plug of polyurethane used to make the chip will be described. This plug is
It has end pieces 200 and 202 configured to fit snugly into lumen 50.52 (FIG. 3). Each of these end pieces has a weak joint.
Hub 20 at ned joints 1210 and 212
spacers 204 and 206 extending from 8. The hub has a central opening 214 that aligns with the third lumen 54 so that wire used in molding can be used to center the hub.

To explain the procedure for using the plug shown in FIG. The end piece is then pushed deeper until the hub 208 meets the end of the body. The end piece 2[)0.202 is automatically placed in the required position controlled by the length of the spacers 204, 206. First, molding is performed as described above to form the hub and spacer. Integrate the adjacent parts with the chip.

FIG. 11 shows yet another embodiment of the invention. The structure of this example includes a separate molded tip 2J6, preferably made of polyurethane;
This chip is engaged and fixed to the end of the extrusion. The tip 216 is externally conical and defines a central opening 218 that forms a continuation of the third lumen 220 . A pair of extension members 222 and 224 are formed to fit within lumens 226 and 228, respectively, and have a length that allows alignment of openings 230 and 232 in the lumen sidewalls. The ends of the extension members are shaped to align the apertures and provide a natural flow pattern;
It is preferred that voids be substantially eliminated, or if eliminated, minimized.

The structure shown in FIG. 11 can also be partially formed by heating in a mold to merge the joints between the chip and the extrusion.

This technique can also be used when it is necessary to partially form an assembly to improve the chip.

The shaping of the ends can be done by softening the plastic material using a high frequency heating device. Radiofrequency heating is one example of a softening technique; other techniques, such as the use of electric heating elements, are equally effective.

A third method of manufacturing the chip is shown in FIG. In FIG. 12, members corresponding to those shown in FIG. 3 are indicated by the same reference numerals with a prefix "3" and two fingers.

In this embodiment, the body 326 has an extension 402 formed to fit loosely into the end of the body and having a protrusion 402 shaped as necessary to act as a continuation of the central opening or third lumen. I received 400 pieces. These members are arranged relative to each other by a central rod 404 within two heating die halves 406 and 408 that are shaped to correspond to the shape of the chip shown in FIG. Of course, this arrangement can be varied to change the end of the catheter depending on the desired configuration.

Body 326 is configured to fit within lumens 350 and 352 and such that material that flows when heated engages the ends in a manner corresponding to plugs 56 and 60 shown in FIG. The first mandrel 410 and the second mandrel arranged
Mandrel 412 is used. This allows material to be transferred from the tip of the catheter to mandrels 410 and 412.
It becomes continuous to the end. This configuration uses plug 5
6. It can be similar to FIG. 3, except that there is no void between 6.60 and the solid end of the catheter.

Under the influence of heat, the material of the body 326 and extension piece 400 flows and forms the closed die halves 406 and 408.
molded by. The amount of material required for complete formation can be increased by providing a plug in the lumen 350, 352 of material that also flows under the influence of heat. However, with some construction care, it is possible to complete the chip without these plugs.

The structure shown in FIG. 12 has the required durometer hardness (
durometer hardness), thus making it possible to form the tip of the tip with different properties than the main body. The tip of the catheter itself can be extremely flexible so that it has minimal strength when inserted, thereby reducing the risk of damaging the vein wall after insertion. Such a tip allows the catheter to be held in place for a longer period of time than is possible with a tip having a strong end.

Various other changes may be made to the methods of manufacturing the catheters and catheter components described above without departing from the scope of the invention. For example, the materials used to form the tubes and inserts may be , any suitable medical grade thermoplastic resin. Furthermore, the location of the openings and the number of openings can be selected to some extent.

And the length of the conical tip can be varied to have an opening in the wall of the tip. Although this configuration is more complex to manufacture, it provides advantageous flow patterns.

The catheter described above is preferably made from thermoplastic material. In some cases it may be preferable to use a thermoset material such as silicone, in which case the structure will be made without a thermoforming process. A method of forming the tip using attached separate end pieces can be used.

This allows the body and chip materials to be made of thermoplastic rather than thermoplastic material.
It can be thermosetting. A similar structure also
within the scope of the present invention.

Although the catheter of the present invention has been described for use in hemodialysis in the subclavian vein, it can also be used in both the right femoral vein and the jugular vein, as well as for apheresis, hemodialysis, and hemodialysis.
It can also be used for other blood treatments, including moperfus 10n), as well as non-blood related treatments, including nutrition and drug therapy.

(Effects) As described above, the catheter of the present invention not only performs the function of hemodialysis, but also allows intravenous injection without further puncturing the patient's vein, and substantially prevents deformation of the catheter tip. It can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a schematic view showing a triple lumen catheter according to a preferred embodiment of the present invention being inserted into the subclavian vein of a patient, FIG. 2 is an enlarged schematic perspective view of the catheter shown in FIG. 1, and FIG. The figure is an enlarged sectional view taken along line 3-31J in Fig. 2 showing the distal end of the catheter in Fig. 1, Figures 4 and 5 are enlarged sectional views taken along lines 4-4 and 5-5 in Fig.
3 is an end view of the catheter seen from the direction indicated by arrow 6 in FIG. 3, and FIG. 7 is a sectional view similar to FIG. 3 showing the distal end of a catheter according to another embodiment of the present invention. FIG. 8 is a sectional view taken along the line 8-8 in FIG. 7, FIG. 9 is a sectional view showing still another embodiment of the catheter of the present invention, and FIG. FIG. 11 is a sectional view showing a catheter according to a further embodiment of the present invention using a separate coupling tip; FIG. 12 is a perspective view of a plug used in the manufacture of a tip according to the present invention. FIG. 7 is a cross-sectional view showing another method. 20... Triple lumen catheter, 21... Guide wire, 22... Bandage, 23... Installation tool, 24...
...Wing tab, 26...Cylindrical body, 28...
Tip part, 29... Conical tip, 30... Trifurcated connector, 32... Removal tube, 34... Return tube, 35... Intravenous (IV) tube, 36, 37
...Joint, 38...Closure clamp, 39...
For installation, 40...Central tubular part, 42...Reinforcement part,
44... Opening, 46... Outer wall, 48... Partition wall, 5
0...Takeout lumen, 53...Return lumen, 5
4... Vein (rv) lumen, 56. 60... Insert, 64... Vein opening, 66... Wire, 68...
...Mold, To, 72 ...End, 128...
Tip, 129...Tip, 146...Outer wall,
148 ... Bulkhead, 150,152 ... Lumens, 156.160 ... Insert, 168 ...
Mold, 200.202 ... End piece, 204.2
06...Spacer, 208...Hub, 210.
212...Weak joint, 214...Central opening, 326...Body, 350.352...
Lumen, 400...Extension piece, 402...Protrusion, 404...Rod, 406°408...Half part of die, 410.412...Mandrel. Engraving of drawings (no changes to content)

Claims (25)

[Claims] (1) a flexible elongated body extending about a longitudinal axis and having a distal end with a tapered tip and a proximal end, the body extending from the proximal end to a respective opening in the body; It has three lumens extending to
two of the lumens have similar cross-sectional shapes and terminate in openings disposed on the sides of the body;
The remaining lumen, a third lumen, extends centrally along the axial direction of the body between the two lumens along the length of the body and terminates at the tip; A catheter having a cross section smaller than the lumen and configured to slidably receive a Seldinger wire for insertion. (2) a flexible elongated body having a distal end extending about a longitudinal axis and having a tapered tip, a proximal end, an outer wall, and a septum extending between spaced apart portions on the outer wall; , the outer wall of the body and the septum define first and second lumens extending from the proximal end to the tapered tip, and the outer wall and the septum merge at the tapered tip to close the lumen; further has first and second openings for fluidly communicating the first and second lumens with the exterior of the body, and the septum extends axially along the body from the proximal end to the distal end. and having a portion defining a third lumen terminating in a tapered tip within the third opening. 3. The multi-lumen catheter of claim 2, wherein the flexible elongate body is cylindrical. 4. The multi-lumen catheter of claim 3, wherein the septum extends between two diametrically opposed portions of the outer wall of the body. (5) The multi-lumen catheter of claim 2, wherein the tapered tip is conical. 6. The multi-lumen catheter of claim 2, wherein the tapered tip has a concentration of material. 7. The multi-lumen catheter of claim 2, wherein the flexible elongate body is formed as an extrusion. 8. The multi-lumen catheter of claim 2, wherein the flexible elongated body has a smooth outer surface. (9) The multi-lumen catheter according to claim 2, wherein the first and second lumens are occluded except for their distal ends by inserts fixed within the lumens. 10. The multi-lumen catheter of claim 9, wherein the insert is coupled to a convergent portion of the septum and the outer wall to fill the space between the opening and the distal end of the catheter. (11) The multi-lumen catheter according to claim 9, wherein the first lumen is further occluded from the distal end than the second lumen. 12. The multi-lumen catheter of claim 2, wherein the first and second openings have navicular edges. (13) The multi-lumen catheter according to claim 2, wherein the first opening is located farther from the distal end than the second opening. 14. The multi-lumen catheter of claim 2, wherein the plurality of first openings are provided to provide fluid communication between the first lumen and the exterior of the body. 15. The multi-lumen catheter of claim 2, wherein the second opening is located adjacent the tapered tip. 16. The multi-lumen catheter of claim 2, wherein a plurality of second openings are provided to provide fluid communication between the second lumen and the exterior of the body. 17. The multi-lumen catheter of claim 2, wherein the third opening has a circular rim. 18. The multi-lumen catheter of claim 2, wherein the first and second lumens have substantially the same cross-sectional area and the third lumen has a smaller cross-sectional area. 19. The multi-lumen catheter of claim 2, wherein the septum has a circular cross section to accommodate the third lumen. (20) Claim 2, wherein the partition wall has a flat side surface, and the first and second lumens have a D-shaped cross section.
Multi-lumen catheter described in. 21. The multi-lumen catheter of claim 2, wherein the body terminates proximally in a generally trifurcated connector. 22. The multi-lumen catheter of claim 21, wherein the proximal ends of the first and second lumens flare outwardly and terminate in the first and second circular openings, respectively. . (23) The multi-lumen catheter of claim 21, wherein the proximal ends of the first, second, and third lumens are connected to the first, second, and third tubes, respectively. (24) A method for manufacturing a multi-lumen catheter having a tapered conical tip concentric with the catheter body and an end opening, comprising: a distal end extending about a longitudinal axis; a proximal end;
an exterior wall; first and second walls extending between spaced apart portions of the exterior wall;
a flexible elongate body having a septum defining a third lumen extending along a longitudinal axis from a proximal end to a distal end with a portion of the first and second lumens; inserting a straight wire into the third lumen extending from the distal end of the body; and placing the body in a tapered conical mold having an opening centrally disposed to receive the wire. inserting the tip; and softening the tip of the body in a mold such that the tip of the body deforms into a conical shape and the outer wall of the body merges with the septum to close the first and second lumens. and forming an opening in the outer wall between the insert and the proximal end. (25) The method of manufacturing a multi-lumen catheter according to claim 24, wherein the insert is fixed in the first and second lumens at a distance from the distal end portion in the axial direction.