JPH07265440A - Tubular medical treatment implement - Google Patents

Abstract

PURPOSE:To provide a tube for medical treatment which is applied to a tubular medical implement having an internal cavity continuous from a front end to a base end and has flexibility, insertability to the blood vessels, etc., and passability. CONSTITUTION:The front end 3 of an introducing tube 2 of the tubular medical treatment implement is coated with a metallic thin film 4 having a film thickness of 0.3 to 105mum. In addition, the difference in the modulus of elasticity at the front end 3 before and after the coating is so regulated as to attain <=30% of the modulus of elasticity before coating. The tube maintains operability by maintaining flexibility over the entire part of the introducing tube and the fine splitting at the front end is prevented by reinforcing the front end 3. The insertability and durability of the tube for medical treatment are thus improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an indwelling tube used for introducing a catheter or the like into the body,
The present invention relates to a tubular medical device used as a catheter for expanding or removing a narrowing in a body cavity (a blood vessel or the like) or a clogging caused by a thrombus.

[0002]

2. Description of the Related Art A medical tube made of a plastic material, for example, a tip of an indwelling tube in the body, is tapered to improve the insertability into the skin, the ability to pass through blood vessels and the narrowing of blood vessels. It is common practice to improve the passability. However, the sharper the tapered tip, the better the passability and insertability, but as long as the material forming these tubes is plastic,
When such a shape is adopted, the tip becomes thin and thus weakened, and there is a possibility that the tip may be squeezed, squeezed by the hand, and eventually the blood vessel may be pierced. On the contrary, in order to avoid the above defects, harden the material,
If the wall thickness of the tube is increased, the entire medical device becomes harder and loses its flexibility, making it difficult to operate. Many.

[0003]

SUMMARY OF THE INVENTION In view of the above situation, the inventor has found that the medical tube has flexibility and permeability,
The present invention has been completed by studying a medical tubing having a safe introduction property, conceiving that the tip of a plastic tube may be coated with a metal thin film, and conducting tests on the coating conditions.

[0004]

Thus, according to the present invention, there is provided a flexible medical tube having a continuous lumen from the distal end to the proximal end, the distal end having a thickness of 0.3 to 105 μm.
And the difference in elastic modulus between the tip after coating and the tip before coating is 30 times the elastic modulus of the tip before coating.
Provided is a tubular medical device characterized in that it is less than or equal to%. As the medical tube to which the present invention is applied, for example, one having an outer diameter of about 1 French (about 0.4 mm) to 18 French (about 6 mm) is used, and the material of the plastic is polyurethane, fluororesin, poly Vinyl chloride, polyethylene terephthalate, polyethylene, polypropylene, polycarbonate, polyamide, acrylic-styrene copolymer, and silicon resin are used.

The length of the tip portion which covers the outer surface of the tube with the metal thin film is 0.2 mm to 80 mm from the tip. 0.
If it is less than 2 mm, accurate coating is difficult and the coating effect cannot be obtained, and if it exceeds 80 mm, there are many hard parts, flexibility is lowered, operability is deteriorated, and it is economically disadvantageous. Next, the thickness of the coated metal thin film is 0.3 μm to 1
If the thickness is less than 0.3 μm in the range of 05 μm, the coating effect may not be obtained because the tip may be squeezed or may be squeezed to the hand, and if it exceeds 105 μm, it is too hard and the operability is poor and economically economical. It will be a disadvantage. The preferred range is 2-9
This is because, in the range of 5 μm, if the thickness is 2 μm, the strength of the tip portion and the covering effect can be sufficiently secured, and if it is 95 μm, good operability can be maintained. As the coating metal,
Titanium, nickel, chromium, bismuth, tungsten,
Paradium, platinum, gold, silver, copper, zinc, lead, aluminum and alloys thereof are used. As a method for coating the metal, means such as electroplating, chemical plating, vacuum deposition, metal spraying, and application of metal paint can be used.

It is necessary for the medical tube to maintain operability, that is, flexibility, and it is preferable that the bending elastic modulus does not change even if the tube is covered with a metal. However, in general, the metal coating tends to make the tube hard and increase the flexural modulus. Therefore, in the present invention, this problem has been solved by defining the bending elastic modulus after coating with a metal thin film. That is, the bending elastic modulus E ₁ without metal coating at the tip end,
The bending elastic modulus E ₂ of the coated material is defined as (E ₂ −E ₁ ) / E ₁ to 30% or less. If this value exceeds 30%, it becomes hard and flexibility decreases, and operability deteriorates.
The bending elastic modulus supports two points on both sides of the pipe (outer diameter D, inner diameter d) with an interval L (mm), and a load W (k
gf), the central displacement Y (mm) is measured, and the second moment of inertia I of the circular pipe according to the following formula 1
(Mm ⁴ ) was obtained, and this value was substituted into Equation 2 to calculate the bending elastic modulus E (kgf / mm ² ).

[0007]

## EQU1 ## I = π × (D ⁴ −d ⁴ ) / 64

[0008]

[Equation 2] E = (L ³ × W) / (48 × I × Y)

[0009]

According to the present invention, the distal end portion is coated with a metal thin film, the coating film thickness and the bending elastic modulus value due to the coating are specified, and the thickness of the metal thin film is appropriately selected within this range to provide a medical tube. The flexibility of the entire tube required for the operation is maintained, the tip is squeezed, the bending during insertion,
It is possible to prevent curling, prevent damage to blood vessels, and improve durability. In addition, by selecting the type of coating metal and the length or thickness of the coating, it can be used as an electrode of a catheter. Furthermore, in the medical device used for treatment or inspection using X-rays, the position of the medical device It can also be used as a mark (RO ring) to check the inside of the body.

[0010]

EXAMPLES The present invention will be described in more detail with reference to the following examples. In FIG. 1, the present tubular medical device is applied as an introduction tube for an indwelling tube, in which a hub portion 1 is attached to the proximal end of the introduction tube 2 and a distal end portion 3 is covered with a metal thin film 4. The material of the introduction tube of the indwelling tube is polyurethane, the length of the introduction tube is 10 cm, the inner diameter is 9 French, the tube thickness is 0.2 mm, and the tip portion is tapered. Platinum plating was applied over 20 mm from the tip. For plating, polyurethane tubes are degreased, etched, treated with alkali, neutralized and activated by applying a catalyst by a known method, then immersed in a platinum electroless bath, and various thicknesses are prepared by varying the immersion time. did. Using the indwelling tube thus obtained, the carotid artery or inferior abdominal artery of a goat was pierced through the skin 10 times, and the insertability and durability were tested. The results are shown in Table 1.

[0011]

[Table 1]

Note: Difference in flexural modulus%: (Bending elastic modulus after coating-Bending elastic modulus before coating) and the ratio of bending elastic modulus before coating in%. Insertability ◯: Insertion was possible without problems even after 10 times. Δ: Deflection and turning over may occur during insertion. ×: Deflection occurred during insertion, and blood vessels were damaged. Durability ◯: Insertion was possible 10 times without any problems, and no burrs or cracks were formed at the tip. Δ: The tip was squeezed and cracked from the sixth insertion. X: The tip was squeezed and cracked from the second insertion.

As shown in the above Examples, Example 1 having a thin metal thin film has a slightly low durability, but there is no problem in practical use, and Examples 2 and 3 have excellent insertability and durability. . In the comparative examples in which the thickness of the metal thin film is out of the range of the present invention or the difference in bending elastic modulus is out of the range of the present invention, the insertability or the durability is remarkably poor.

[0014]

INDUSTRIAL APPLICABILITY The indwelling tube to which the tubular medical device of the present invention is applied and the catheter for expanding or removing stenosis in body cavity (blood vessel etc.) or clogging due to thrombus are excellent in insertability and durability. It can be used as an electrode or for confirming the tip of an X-ray medical examination, and is very useful as a medical device.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a body indwelling tube to which a tubular medical device of the present invention is applied.

[Explanation of symbols]

 1 hub part 2 introduction pipe 3 tip part 4 metal thin film

Claims (1)

[Claims] 1. A flexible medical tube having a continuous lumen from the distal end to the proximal end, wherein the distal end portion has a thickness of 0.3 to
A tubular medical device coated with a metal thin film having a thickness of 105 μm, and a difference in elastic modulus between the coated tip and the uncoated tip is 30% or less of the elastic modulus of the tip before coating. .