JPH0530443Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a digestive tract catheter used in the digestive tract (stomach, duodenum).

[Prior Art] A gastrointestinal catheter is placed in a patient's gastrointestinal tract and performs various functions such as evacuation of contents, suction, irrigation, injection of drug solutions and contrast media, decompression of intragastric pressure after surgery, and nutritional support. The conditions that a catheter must meet are: (1) It should be easy to insert, that is, it should pass quickly through the throat and not coil around the esophagus, it should not damage internal organ lumens, and it should be easy to contrast; It needs to be able to enter the digestive tract quickly, and for this purpose, it needs to be able to easily pass through the pylorus of the stomach, and it needs to be able to easily advance into the duodenum by peristalsis, and it is also required to be able to be reinserted. This is because the patient may consciously or unconsciously withdraw the catheter.

(2) It must be able to be used for the required period of time, that is, it can withstand gastric juices, not break or cut during the period of use, and not cause blockage, and the apical olive (when progressing,
(3) In addition to nutrient solution, other medicinal solutions can be injected.

(4) The introduction tube must be thin, biocompatible, and unobtrusive to avoid giving the patient a foreign body sensation. etc. are required.

For this purpose, it is preferable that the introduction tube has elasticity and appropriate hardness, and is very flexible since it enters the stomach by peristalsis after reaching the stomach.

Conventionally, there have been commercially available tubes in which an elastic core for introduction is inserted into a flexible introduction tube to maintain the shape and allow the tube to reach a desired site in the gastrointestinal tract.
The core wire for introduction (mandolin, hereinafter referred to as mandolin) is, for example, JP-A-62-66866.
Twisted wire, ie, a solid metal wire wound into a thin spiral tube, has been used, such as that used in However, this helical wire undergoes plastic deformation and bends when the displacement exceeds a certain level, impairing its ability to be flexibly delivered to a predetermined area, or causing the tip to be pulled out from the olive area, resulting in a great deal of difficulty in the procedure. It takes time, effort, and can be dangerous. As this improvement method, Utility Model 60-138547
proposed a flexible substantially tubular body in which at least a portion of a superelastic metal body is attached as an inner core. Although this product does not have the above-mentioned drawbacks such as curved curls, it is made by inserting an inner core into a tubular body to form a mandolin, and there is a limit to the thinness of the diameter of the mandoline, and the inner core is relatively rigid. It has a complicated structure consisting of a high body part and a relatively flexible tip part, resulting in high cost.

[Problems that the invention aims to solve] The inventors focused on the fact that, unlike blood vessels, the lumen of the digestive tract has a relatively gentle curve and a large lumen diameter for the mandolin catheter for the gastrointestinal tract.
We discovered that it is sufficient to prevent plastic deformation of the mandolin even with a simple structure, and completed the present invention.

[Means for Solving the Problems] Thus, according to the present invention, an olive is connected to the catheter base and has a side hole at its distal end, and the intersection of the axis of the side hole and the center line of the olive on the catheter base side is Provided is a digestive tract catheter structure comprising a soft introduction tube with an acute angle and a mandolin inserted through the introduction tube, wherein the mandolin is a single metal wire made of a superelastic metal body. be done.

The present invention prevents the mandolin from bending by using a single wire made of superelastic metal as the mandolin. That is, it utilizes the phenomenon that even if a superelastic metal alloy is greatly deformed by load (stress) in a certain temperature range, it returns to its original shape when the load is removed.

Ti-Ni is a superelastic metal wire for mandolin.
Alloys are common, and Cu-Zn-Al alloys are also used. As the mandoline, the above-mentioned alloy wire that has not been twisted is used, and a wire diameter of about 0.4 mm to 1.2 mm is suitably used for gastrointestinal catheters.

To explain the present invention based on the drawings, Fig. 1 is a partially omitted front view in which the catheter base 1 is attached to the introduction tube 2, the olive 3 is attached to the distal end, and the mandoline 4 is attached to the introduction tube from the catheter base. inserted, and its tip reaches the tip of the olive.

The catheter base 1 is made of medium hard plastic.
A type with a luer taper is used, and as shown in FIG. 2, it is formed of a cylindrical part 5 for injecting the main agent and inserting a mandolin, and a branch pipe 6 branching from the cylindrical part.

The catheter base 1 is made from commonly used catheter base materials such as vinyl chloride, polyethylene, polypropylene, nylon, etc.

In this embodiment, the introduction tube 2 has an outer diameter of 2.0 mm and an inner diameter of 1.5 mm, and the tube wall includes a contrast line 7 containing 20% barium sulfate as a contrast agent. In addition, the 2 to 3 cm part near the olive is for installing the olive, so make the pipe diameter a little thicker, and
It may be a little hard. Since the introduction tube is subject to peristalsis, it is preferably as flexible as possible and is made of a soft plastic material such as polyurethane, silicone resin, etc.

As shown in FIG. 3, the mandolin 4 may have a single superelastic metal wire extending from the base of the mandolin provided with the operating wings 8, if necessary. It should be noted that the blade may be used without providing a wing for operation and with the end portion curved. In this example, the mandolin 4 has a diameter of 0.6 mm.
Ti-Ni alloy wire is used.

Incidentally, the surface of the mandoline may be roughened in order to prevent it from coming into close contact with the inner wall of the introduction tube when the mandolin is inserted into or withdrawn from the introduction tube.

Next, the olive 3 attached to the tip is
For example, it is made of hard plastic such as polyamide, polypropylene, polyester, etc., and as shown in Figure 4, it has a cylindrical shape, and in this example, it has a length of 15 mm.
It has an outer diameter of 5 mm and an inner diameter of 1.5 mm, and a tip hole 9 with a diameter of 0.4 mm is provided at the tip to prevent internal clogging and to prevent the mandolin from penetrating. Further, a side hole 10 is bored in the side portion as an outlet for the nutrient solution. The inner diameter of the side hole is approximately 2.0 mm. It is preferable that the angle of intersection between the axis of the side hole and the center line of the olive on the proximal side of the catheter is less than or equal to a right angle. That is, when a mandolin is inserted into an olive,
This is because even if the tip hits the wall of the side hole, it will not be able to jump out of the side hole, thereby ensuring safety.

If necessary, a hydrophilic polymer film is formed on the olive and the part of the introduction tube that comes into contact with the organ lumen, and also on at least one of the inner surface of the introduction tube and the surface of the mandolin, to prevent insertion of the catheter and the introduction of the mandolin in the introduction tube. It may be possible to make the entry and withdrawal operations easier.

[Function] The digestive tract catheter according to the present invention uses a superelastic metal wire as the mandoline, and therefore has the following functions.

Due to its superelasticity, even if it is bent under load, it will return to its original shape when the load is removed, and no bending will occur. Furthermore, since it is a single metal wire, it is possible to make the wire diameter sufficiently thin. In addition, the lumen of the digestive tract has a relatively gentle curve.
In addition, the lumen diameter is large, and the amount of deformation that reversibly occurs and disappears in the wire is extremely large, so even a single wire can sufficiently reach and indwell the desired site.

[Effects of the invention] According to the catheter for the gastrointestinal tract according to the invention, the mandoline is thin, has appropriate elasticity, and does not cause creases, so the diameter of the introduction tube can be reduced, making insertion and placement easier. The catheter can be smoothly introduced into a predetermined part of the gastrointestinal tract through the nasal cavity or oral cavity. Since mandolin is linear, it is easy to manufacture and is extremely advantageous in terms of manufacturing cost, making it very useful for medical treatment of the gastrointestinal system.

[Brief explanation of the drawing]

Fig. 1 is a partially omitted front view of the catheter for the gastrointestinal tract according to the present invention, Fig. 2 is an enlarged perspective view of the catheter base, Fig. 3 is an enlarged perspective view of the mandolin base, and Fig. 4 is an olive portion. FIG. 1...Catheter base, 2...Introduction tube,
3... Olive, 4... Mandolin, 7... Contrast line, 8... Operation wing piece, 9... Tip hole, 10
...side hole.

Claims (1)

[Claims for Utility Model Registration] 1. A soft introduction tube that is connected to the catheter base and has an olive with a side hole at its distal end, and the intersection angle between the axis of the side hole and the center line of the olive on the catheter base side is an acute angle. and a gastrointestinal catheter structure comprising a mandoline inserted through the introduction tube, wherein the mandoline is a single metal wire made of a superelastic metal body. 2. The digestive tract catheter according to claim 1, wherein at least one of the inner surface of the soft introduction tube or the surface of the mandoline is coated with a highly hydrophilic polymer.