Method for inserting medical device systems and medical elongated objects into blood vessels.

Abstract

This invention provides a medical device system consisting of a medical-grade long body and a dilator, which prevents the medical-grade long body from getting caught due to a step or gap between them during insertion into a blood vessel, and a method for inserting the medical-grade long body into a blood vessel using this system. [Solution] A medical device system comprising a tubular medical elongated body 15 extending along the axial direction and a dilator 10 having a main body 20 inserted into the lumen of the medical elongated body 15, wherein the main body 20 has an umbrella-shaped portion 24 at its tip 22 with a circumferential surface portion 25 extending toward the proximal end, the circumferential surface portion 25 covers at least a portion of the outer surface at the tip of the medical elongated body 15 from the outer circumference, and the umbrella-shaped portion 24 has a curved portion 26 that displaces the circumferential surface portion 25 so as to fold it toward the tip.

Description

Technical Field

[0001] The present invention relates to a medical device system including a long medical body and a dilator used when inserting the long medical body into a blood vessel, and a method for inserting the long medical body into a blood vessel using the medical device system.

Background Art

[0002] ECMO (ExtraCorporeal Membrane Oxygenation) is one of the effective treatment methods in the life-saving treatment for resuscitating patients with cardiac arrest. When using ECMO, a cannula, which is a tubular long medical body, is inserted into a blood vessel. The cannula is required to have less resistance during insertion into the blood vessel, be easy to secure the blood vessel, and be difficult to fall out after indwelling.

[0003] In order to impart rigidity to the cannula to facilitate insertion into the blood vessel, a dilator is inserted into the cannula when inserting it into the blood vessel. The dilator is inserted into the blood vessel with its tip exposed on the tip side of the tip of the cannula. Further, the dilator is not limited to the cannula for ECMO, and is widely used when inserting a long medical body such as a catheter into a blood vessel. The dilator has a tapered portion with a diameter decreasing toward the tip at the tip portion in order to facilitate insertion into the blood vessel. As such a dilator, for example, there is one as described in Patent Document 1. When the dilator is exposed on the tip side of the tip of the long medical body, a step facing the insertion direction occurs between the dilator and the long medical body, which may cause an increase in puncture resistance due to the skin or the like being caught, or a decrease in the operability when introducing the long medical body into the blood vessel. In order to prevent this, Patent Document 1 describes a dilator with a structure that eliminates the step between the dilator and the long medical body.

Prior Art Documents

Patent Documents

[0004] [Patent Document 1] Patent No. 6900499 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] While the dilator described in Patent Document 1 can eliminate the step difference between the medical elongated body and the dilator, it has the problem that the structure used to eliminate the step difference becomes an obstacle when removing the dilator from the medical elongated body, making the removal of the dilator difficult.

[0006] The present invention was made to solve the above-mentioned problems, and aims to provide a medical device system consisting of a medical elongated body and a dilator that prevents snagging due to a step between the medical elongated body and the dilator during insertion into a blood vessel, while simultaneously facilitating the removal of the dilator, and a method for inserting the medical elongated body into a blood vessel using this system. [Means for solving the problem]

[0007] A medical device system (1) according to the present invention that achieves the above objective is a medical device system comprising a tubular medical elongated body extending along the axial direction and a dilator having a main body portion inserted into the lumen of the medical elongated body, wherein the main body portion has an umbrella-shaped portion at its tip having a circumferential surface portion extending toward the proximal end, the circumferential surface portion covers at least a circumferential portion of the outer surface at the tip of the medical elongated body from the outer circumference, and the umbrella-shaped portion has a curved portion that displaces the circumferential surface portion so as to fold it toward the tip.

[0008] A method for inserting a medical elongated body into a blood vessel according to the present invention to achieve the above objective, comprising the steps of: preparing a dilator having a main body extending along the axial direction, the main body having an umbrella-shaped portion at its tip with a circumferential surface portion extending toward the proximal end; and a tubular medical elongated body extending along the axial direction into which the dilator can be inserted; arranging the dilator so that the proximal end position of the umbrella-shaped portion is toward the proximal end position of the medical elongated body, and inserting the dilator into the lumen of the medical elongated body such that the circumferential surface portion covers at least a portion of the outer surface of the tip of the medical elongated body from the outer circumference; inserting the medical elongated body with the dilator inserted into it into a blood vessel; and moving the dilator toward the proximal end side of the medical elongated body so that the circumferential surface portion of the umbrella-shaped portion folds toward the tip, and accommodating it in the lumen of the medical elongated body before removing it. [Effects of the Invention]

[0009] As described above, the (1) medical device system has an umbrella-shaped portion of the dilator that can cover the step between the dilator and the medical elongated body at the tip of the medical elongated body from the outer circumference, so that the step does not get caught and the device can be inserted smoothly into the blood vessel. In addition, because the umbrella-shaped portion has a curved portion, the dilator can be easily removed by retracting the dilator into the medical elongated body and housing the umbrella-shaped portion within the medical elongated body.

[0010] (2) In the medical device system described in (1) above, the base end position of the umbrella-shaped portion is on the base end side of the tip position of the medical elongated body. This ensures that the umbrella-shaped portion covers the tip of the medical elongated body from the outer circumference, thereby reliably covering the step between the medical elongated body and the dilator.

[0011] (3) In the medical device system of (1) or (2) above, the curved portion may be provided at a position on the inner circumference side of the inner diameter of the medical elongated body. This allows the medical device system to smoothly accommodate the umbrella-shaped portion into the lumen of the medical elongated body even if the circumferential portion is folded back at the curved portion.

[0012] (4) In any of the medical device systems described in (1) to (3) above, the inner diameter of the umbrella-shaped portion at the base end of the circumferential portion may be larger than the outer diameter of the tip end of the medical elongated body. This ensures that the tip end of the medical elongated body abuts against the inner surface of the umbrella-shaped portion, and that the umbrella-shaped portion reliably covers the step between the medical elongated body and the dilator.

[0013] (5) In any of the medical device systems described in (1) to (4) above, the main body may have a constricted shape in which the outer diameter decreases from the tip side toward the bent portion and increases toward the base end side toward the bent portion. This allows the medical device system to secure space for the circumferential portion to bend and fold back at the bent portion, and the umbrella-shaped portion to be smoothly housed in the lumen of the medical elongated body.

[0014] (6) In any of the medical device systems described in (1) to (5) above, the circumferential portion may be divided into multiple sections in the circumferential direction. This makes it easier to displace the circumferential portion at the inflection section of the medical device system and to remove the dilator.

[0015] (7) In any of the medical device systems described in (1) to (5) above, the circumferential portion may be continuous around the entire circumference. This ensures that the step between the medical elongated body and the dilator is covered by the umbrella-shaped portion around the entire circumference, preventing the step from being exposed to the outside and more reliably preventing snagging.

[0016] (8) In any of the medical device systems described in (1) to (7) above, the outer diameter of the circumferential portion of the umbrella-shaped portion when it is displaced so as to fold back toward the tip may be smaller than the inner diameter of the medical elongated body. This allows the medical device system to be easily removed because the umbrella-shaped portion is smoothly housed in the medical elongated body.

[0017] The method of inserting the (9) medical elongate body configured as described above into a blood vessel is to insert the medical elongate body into the blood vessel in a state where the step formed between the dilator and the tip of the medical elongate body is covered from the outer peripheral side by the umbrella-shaped portion of the dilator. Therefore, the step is not caught and the medical elongate body can be smoothly inserted into the blood vessel. Further, by pulling the dilator into the medical elongate body, the umbrella-shaped portion is displaced so as to be folded back and housed in the medical elongate body, and the dilator can be easily removed.

Brief Description of the Drawings

[0018] [Figure 1] It is a perspective view near the tip of a medical device system combining the dilator and the medical elongate body of this embodiment. [Figure 2] It is a cross-sectional view near the tip of a medical device system combining a medical device and a medical elongate body. [Figure 3] It is a cross-sectional view of the state where the dilator has started to be pulled into the medical elongate body from the state of FIG. 2. [Figure 4] It is a cross-sectional view of the state where the dilator has been further pulled into the medical elongate body from the state of FIG. 3. [Figure 5] It is a view of the state where the medical device system is about to puncture a blood vessel. [Figure 6] It is a view of the state where the medical device system has punctured a blood vessel. [Figure 7] It is a view of the state where the dilator has been pulled into the lumen of the medical elongate body. [Figure 8] It is a perspective view near the tip of a medical device system according to a modified example. [[ID=三十]]

Modes for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the dimensions in the drawings may be exaggerated for convenience of explanation and may be different from the actual dimensions. In addition, in this specification and the drawings, components having substantially the same function are denoted by the same reference numerals, and redundant description is omitted.

[0020] The medical device system of this embodiment is a combination of a long medical body 15 and a dilator 10 used for inserting the long medical body 15 into a blood vessel. The long medical body 15 is a cannula used in ECMO. However, the long medical body 15 is not limited to a cannula and may be other long bodies used in medical treatment, such as a catheter.

[0021] As shown in FIGS. 1 and 2, the long medical body 15 is formed in a tubular shape extending along the axial direction. The dilator 10 includes a main body portion 20 inserted into the lumen 16 of the long medical body 15. The main body portion 20 has a guide wire lumen 21 extending along the axial direction, and the tip portion 22 is exposed on the tip side of the tip of the long medical body 15.

[0022] The tip portion 22 of the main body portion 20 has an opening 21a of the guide wire lumen 21 at the tip. The tip portion 22 has a tip tapered portion 22a whose outer diameter increases from the opening 21a toward the base end side. Further, the tip portion 22 has an umbrella-shaped portion 24 provided with a peripheral surface portion 25 extending toward the base end side. The peripheral surface portion 25 is connected to the main body portion 20 at the tip, and the outer diameter increases so as to be separated from the surface of the main body portion 20 from the tip toward the base end side. The tip of the peripheral surface portion 25 connected to the main body portion 20 is a bending portion 26 that can be displaced so as to fold back the peripheral surface portion 25 toward the tip side. The peripheral surface portion 25 is divided into a plurality in the circumferential direction, and a space is formed between the peripheral surface portions 25, 25 adjacent in the circumferential direction.

[0023] In the medical device system for insertion into blood vessels, the proximal end of the umbrella-shaped portion 24 is located proximal to the tip of the medical elongated body 15. Furthermore, the inner diameter D1 at the proximal end of the circumferential portion 25 of the umbrella-shaped portion 24 is larger than the outer diameter D2 at the tip of the medical elongated body 15. Therefore, the umbrella-shaped portion 24 covers a portion of the outer surface of the tip of the medical elongated body 15 from the outer circumferential side. Since the dilator 10 is inserted into the lumen 16 of the medical elongated body 15, a step 19 is formed in the direction of insertion at the portion of the dilator 10 that protrudes from the medical elongated body 15 toward the tip. The umbrella-shaped portion 24 covers this step 19 from the outer circumferential side, preventing the step 19 from catching on the skin surface or other objects when the medical elongated body 15 is inserted into a blood vessel.

[0024] The main body portion 20 has a constricted shape where, from the tip tapered portion 22a towards the base end, the outer diameter decreases from the tip side toward the inflection portion 26, and the outer diameter of the circumferential portion 25 increases from the inflection portion 26 toward the base end. This constricted shape allows the circumferential portion 25 to bend and fold back at the inflection portion 26. The outer diameter D3 of the main body portion 20 at the inflection portion 26 is smaller than the inner diameter D4 of the medical elongated body 15.

[0025] The dilator 10 is preferably flexible and possesses a certain degree of suppleness. For this reason, the constituent material of the main body 20 of the dilator 10 can be, for example, various thermoplastic elastomers such as styrene-based, polyolefin-based, polyurethane-based, polyester-based, polyamide-based, polybutadiene-based, trans-polyisoprene-based, fluororubber-based, and chlorinated polyethylene-based, as well as polyether ketones, polyimide-based materials, etc., and one or more of these can be used in combination (polymer alloy, polymer blend, laminate, etc.). Alternatively, among the various elastomers, for example, polyurethane elastomer, polyester elastomer, polyamide elastomer, etc. can be suitably used. Furthermore, the umbrella-shaped portion 24, including the circumferential portion 25 and the curved portion 26, is preferably formed from a more flexible material, such as silicone rubber. The umbrella-shaped portion 24 may also be formed from the same material as the constituent material of the main body 20 of the dilator 10.

[0026] When the dilator 10 is moved towards the base end relative to the medical elongated body 15 from the state shown in Figure 2, the circumferential surface 25 of the umbrella-shaped portion 24 is pressed by the tip surface of the medical elongated body 15, and the curved portion 26 bends and deforms to spread radially, as shown in Figure 3. When the dilator 10 is moved further towards the base end relative to the medical elongated body 15, the circumferential surface 25 of the umbrella-shaped portion 24 is displaced such that the curved portion 26 bends further and folds back toward the tip. The curved portion 26 is located on the inner circumference side of the inner diameter of the medical elongated body 15, and as described above, the constricted shape ensures space for the curved portion 26 to bend and the circumferential surface 26 to fold back. As shown in Figure 4, the circumferential surface 25 that has been folded back toward the tip is housed in the lumen 16 of the medical elongated body 15. The outer diameter of the circumferential portion 25 of the umbrella-shaped portion 24, when displaced so as to fold back toward the tip, is smaller than the inner diameter of the medical elongated body 15.

[0027] Next, a method for inserting a medical elongated body 15 into a blood vessel using a medical device system will be described. Prior to the insertion of the medical elongated body 15, a guidewire 100 is already inserted into the blood vessel 200. The surgeon prepares the dilator 10 and the medical elongated body 15 to be inserted into the blood vessel 210. The surgeon inserts the dilator 10 into the lumen 16 from the tip side of the medical elongated body 15. At this time, the proximal end position of the umbrella-shaped portion 24 is positioned proximal to the tip position of the medical elongated body 15, so that the circumferential portion 25 covers at least a portion of the outer surface of the tip of the medical elongated body 15 from the outer circumference. The medical device system may be prepared with the umbrella-shaped portion 24 and the medical elongated body 15 already positioned in this manner.

[0028] Next, the surgeon inserts the guidewire 100 into the guidewire lumen 21 of the dilator 10, and as shown in Figure 5, inserts the dilator 10 and the medical elongated body 15 into the blood vessel 200 along the guidewire 100. At this time, the step 19 that is created at the tip of the medical elongated body 15 is covered from the outer circumference by the umbrella-shaped portion 24, so that the step 19 does not catch on the skin surface or the like, and the medical elongated body 15 can be inserted smoothly.

[0029] As shown in Figure 6, the medical elongated body 15 is inserted into the blood vessel 200 together with the dilator 10. From this state, as shown in Figure 7, when only the dilator 10 is moved towards the proximal end, the umbrella-shaped portion 24 bends at the inflection portion 26, and the circumferential portion 25 is displaced so that it folds back toward the tip. Since the circumferential portion 25 is flexible and deformable, it can easily be deformed into the folded shape within the blood vessel 200. As a result, the umbrella-shaped portion 24 is housed in the lumen 16 of the medical elongated body 15, and the dilator 10 can be removed from the medical elongated body 15. Once the dilator 10 has been removed from the medical elongated body 15, treatment with the medical elongated body 15 can be started.

[0030] A modified example of the umbrella-shaped portion will now be described. As shown in Figure 8, the umbrella-shaped portion 27 provided on the tip portion 22 of the dilator 10 may have a circumferential surface portion 28 that is continuous around its entire circumference. In this case as well, the tip of the circumferential surface portion 28 is a curved portion 29, and by bending the curved portion 29, the circumferential surface portion 28 can be displaced so as to fold back toward the tip side.

[0031] As described above, the (1) medical device system according to this embodiment is a medical device system comprising a tubular medical elongated body 15 extending along the axial direction and a dilator 10 having a main body portion 20 inserted into the lumen of the medical elongated body 15, wherein the main body portion 20 has an umbrella-shaped portion 24 at its tip portion 22 with a circumferential surface portion 25 extending toward the proximal end, the circumferential surface portion 25 covers at least a portion of the outer surface of the tip portion of the medical elongated body 15 from the outer circumferential side, and the umbrella-shaped portion 24 has a curved portion 26 that displaces the circumferential surface portion 25 so as to fold it toward the tip side. With the medical device system configured in this way, the umbrella-shaped portion 24 of the dilator 10 can cover the step created between the medical elongated body 15 and the dilator 10 at the tip from the outer circumferential side, so that the step does not get caught and the dilator can be smoothly inserted into the blood vessel. Furthermore, since the umbrella-shaped portion 24 has a curved portion 26, the dilator 10 can be easily removed by retracting it into the medical elongated body 15, thereby housing the umbrella-shaped portion 24 within the medical elongated body 15.

[0032] (2) In the medical device system described in (1) above, the base end position of the umbrella-shaped portion 24 is on the base end side of the tip position of the medical elongated body 15. As a result, the medical device system can reliably cover the step between the medical elongated body 15 and the dilator 10 by having the umbrella-shaped portion 24 cover the tip of the medical elongated body 15 from the outer circumference side.

[0033] (3) In the medical device system of (1) or (2) above, the curved portion 26 may be provided at a position on the inner circumference side of the inner diameter of the medical elongated body 15. This allows the medical device system to smoothly accommodate the umbrella-shaped portion 24 into the lumen of the medical elongated body 15 even when the circumferential portion 25 is folded back at the curved portion 26.

[0034] (4) In any of the medical device systems described in (1) to (3) above, the inner diameter of the umbrella-shaped portion 24 at the base end of the circumferential portion 25 may be larger than the outer diameter of the medical elongated body 15 at the tip. This ensures that the tip of the medical elongated body 15 abuts against the inner surface of the umbrella-shaped portion 24, and that the umbrella-shaped portion 24 reliably covers the step between the medical elongated body 15 and the dilator 10.

[0035] (5) In any of the medical device systems described in (1) to (4) above, the main body 20 may have a constricted shape in which the outer diameter decreases from the tip side toward the bendable portion 26 and the outer diameter of the circumferential portion 25 increases toward the base end side from the bendable portion 26. This allows the medical device system to secure space for the circumferential portion 25 to bend and fold back at the bendable portion 26, and allows the umbrella-shaped portion 24 to be smoothly housed in the lumen of the medical elongated body 15.

[0036] (6) In any of the medical device systems described in (1) to (5) above, the circumferential portion 25 may be divided into multiple circumferential portions. This makes it easier to displace the circumferential portion 25 at the inflection portion 26 and to remove the dilator 10.

[0037] (7) In any of the medical device systems described in (1) to (5) above, the circumferential portion 25 may be continuous around its entire circumference. This ensures that the step between the medical elongated body 15 and the dilator 10 is covered by the umbrella-shaped portion 24 around its entire circumference, preventing the step from being exposed to the outside and more reliably preventing snagging at the step.

[0038] (8) In any of the medical device systems described in (1) to (7) above, the outer diameter of the circumferential portion 25 of the umbrella-shaped portion 24 when it is displaced to fold back toward the tip may be smaller than the inner diameter of the medical elongated body 15. This allows the medical device system to be easily removed because the umbrella-shaped portion 24 is smoothly housed in the medical elongated body 15.

[0039] The method of inserting the medical elongated body 15 into a blood vessel in this embodiment (9) is a dilator 10 having a main body 20 extending along the axial direction, the main body 20 having an umbrella-shaped portion 24 at its tip 22 with a circumferential portion 25 extending toward the proximal end, and a medical elongated body 15 that is tubular and extends along the axial direction and can be inserted into the lumen of the dilator 10, and arranging the medical elongated body 15 so that the proximal end position of the umbrella-shaped portion 24 is toward the proximal end position of the tip 15, and the circumferential portion 25 is medical The method for inserting a medical elongated body 15 into a blood vessel includes the steps of: inserting the dilator 10 into the lumen of the medical elongated body 15 so as to cover at least a portion of the outer surface of the tip of the medical elongated body 15 from the outer circumferential side; inserting the medical elongated body 15 with the dilator 10 inserted into it into a blood vessel; and moving the dilator 10 toward the proximal end of the medical elongated body 15 so as to displace the circumferential portion 25 of the umbrella-shaped portion 24 toward the tip, thereby housing it in the lumen of the medical elongated body 15 and removing it. In this method of inserting a medical elongated body 15 into a blood vessel, the medical elongated body 15 is inserted into the blood vessel with the umbrella-shaped portion 24 of the dilator 10 covering the step created between the medical elongated body 15 and the dilator 10 at the tip of the medical elongated body 15 from the outer circumferential side, so that the step does not get caught and the medical elongated body 15 can be inserted smoothly into the blood vessel. Furthermore, by retracting the dilator 10 into the medical elongated body 15, the umbrella-shaped portion 24 is displaced so as to fold back, allowing it to be housed in the medical elongated body 15 and the dilator 10 to be easily removed.

[0040] It should be noted that the present invention is not limited to the embodiments described above, and various modifications can be made by those skilled in the art within the technical framework of the present invention. In the embodiments described above, the inflection portion 26 is configured as an easily deformable portion continuous with the circumferential portion 25 and the main body portion 20, but it may also be configured as a mechanical means such as a hinge. [Explanation of Symbols]

[0041] 10 dilators 15 Medical-grade long body 16 lumen 19 steps 20 Main body 21 guide wire lumens 22 Tip 24 Umbrella 25 Peripheral part 26 Inflection 100 guide wires 200 blood vessels

Claims

1. A medical device system comprising a tubular medical elongated body extending along the axial direction, and a dilator having a main body portion inserted into the lumen of the medical elongated body, The main body portion has an umbrella-shaped portion at its tip, which has a circumferential portion extending toward the base end, and the circumferential portion covers at least a portion of the outer surface at the tip of the medical elongated body from the outer circumference. The aforementioned umbrella-shaped portion is a medical device system comprising a curved portion that displaces the circumferential portion so as to fold it back toward the tip.

2. The medical device system according to claim 1, wherein the base end position of the umbrella-shaped portion is on the base end side of the tip position of the medical elongated body.

3. The medical device system according to claim 1 or 2, wherein the curved portion is provided at a position on the inner circumference side of the inner diameter of the medical elongated body.

4. The medical device system according to claim 1 or 2, wherein the inner diameter of the umbrella-shaped portion at the base end of the circumferential portion is greater than the outer diameter of the medical elongated body at the tip end.

5. The medical device system according to claim 1 or 2, wherein the main body portion has a constricted shape in which the outer diameter decreases from the tip side toward the bent portion and increases toward the base end side toward the bent portion.

6. The medical device according to claim 1 or 2, wherein the circumferential portion is divided into a plurality of parts in the circumferential direction.

7. The medical device according to claim 1 or 2, wherein the circumferential surface is continuous over its entire circumference.

8. The medical device according to claim 1 or 2, wherein the outer diameter of the circumferential portion in a state where the umbrella-shaped portion is displaced so as to be folded back toward the tip is smaller than the inner diameter of the medical elongated body.

9. The steps include: preparing a dilator having a main body that extends along the axial direction, the main body having an umbrella-shaped portion at its tip with a circumferential surface portion that extends toward the base end, and a long medical body that is tubular and extends along the axial direction and into which the dilator can be inserted; The steps include: positioning the umbrella-shaped portion so that its base end is on the base side of the tip end of the medical elongated body, and inserting the dilator into the lumen of the medical elongated body such that the circumferential portion covers at least a portion of the outer surface of the tip end of the medical elongated body from the outer circumference; The steps include inserting the medical elongated body into which the dilator has been inserted into a blood vessel, The dilator is moved toward the proximal end of the medical elongated body, thereby displacing the circumferential portion of the umbrella-shaped part so that it folds toward the tip, and is then housed in the lumen of the medical elongated body and removed. A method for inserting a medical-grade, elongated instrument into a blood vessel.

Images