MEDICAL CATHETER FOR HYPOTHERMIC TREATMENT

Abstract

A medical catheter for hypothermic treatment has a catheter tube, which has at least two inner lumina. At least one inner lumen forms a temperature control duct that is suitable for in particular provided for, conveying a cooling liquid. A reinforcement is associated with at least one inner lumen.

Claims

1. A medical catheter for hypothermia treatment with a catheter tubing, the medical catheter comprising: a first inner lumen and a second inner lumen, the first inner lumen forming a temperature control duct adapted for conveying a cooling liquid, and a reinforcement associated with the first inner lumen or the second inner lumen.

2. The catheter according to claim 1, wherein the second inner lumen forms a through-duct, the through-duct being separated from the temperature control duct, and wherein the reinforcement is associated with the through-duct or the temperature control duct.

3. The catheter according to claim 1, wherein the reinforcement lines the first inner lumen or the second inner lumen and comprises a material different from a material of the catheter tubing.

4. The catheter according to claim 1, wherein the reinforcement comprises a structuring or a grooved longitudinal contour.

5. The catheter according to claim 4, further comprising the catheter tubing, wherein the structuring is formed in the material of the catheter tubing or in the material of the reinforcement.

6. The catheter according to claim 1, wherein the reinforcement comprises two materials in multiple layers or more than two materials in multiple layers.

7. The catheter according to claim 1, wherein the reinforcement has a metallic mesh or a metallic coil.

8. The catheter according to claim 1, wherein the reinforcement extends over an entire inside circumference of the first inner lumen or an entire inside circumference of the second inner lumen.

9. The catheter according to claim 1, wherein the reinforcement extends over an entire length of the first inner lumen or an entire length of the second lumen.

10. The catheter according to claim 1, further comprising the catheter tubing, wherein the catheter tubing is formed in one piece.

11. The catheter according to claim 1, wherein at least one inner lumen forms a through-duct.

12. The catheter according to claim 1, the through-duct has an essentially circular cross-sectional basic shape.

13. The catheter according to claim 1, further comprising the catheter tubing; wherein the first inner lumen and the second inner lumen are temperature control ducts wherein the catheter tubing carries a heat exchanger element that is arranged on a distal catheter section of the catheter tubing and is fluidically connected to the temperature control ducts for a temperature control circulation wherein the heat exchanger element is an expandable balloon.

14. The catheter according to claim 1, further comprising a third inner lumen and a fourth inner lumen, wherein at least three inner lumens are lined with the reinforcement.

15. The catheter according to claim 14, further comprising the catheter tubing; wherein the reinforcements of neighboring inner lumens are separated from one another by the material of the catheter tubing.

Description

BRIEF DESCRIPTION OF THE INVENTION

[0044] The invention is explained in greater detail below on the basis of exemplary embodiments with reference to the accompanying schematic drawings, in which:

[0045] FIG. 1: shows how a cross-sectional view through the catheter tubing of a catheter according to the invention in a first exemplary embodiment;

[0046] FIG. 2: shows a cross-sectional view through the catheter tubing of a catheter according to the invention in a second exemplary embodiment;

[0047] FIG. 3: shows a cross-sectional view through the catheter tubing of a catheter according to the invention in a third exemplary embodiment; and

[0048] FIG. 4: shows a cross-sectional view through the catheter tubing of a catheter according to the invention in a fourth exemplary embodiment;

[0049] FIGS. 5a-c: show a longitudinal sectional view, a side view and a frontal view of a catheter according to the invention in a fifth exemplary embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0050] The accompanying drawings each show a cross-sectional view through a catheter tubing 10, wherein the catheter tubing 10 has three inner lumens 11, 12, 13. Two inner lumens 12, 13 are designed as temperature control ducts 12, 13. The third inner lumen forms a through-duct 11.

[0051] All these exemplary embodiments have in common the fact that the through-duct 11 has a larger cross-sectional diameter than the temperature control ducts 12, 13. The inner lumens 11, 12, 13 of the through-duct 11 in particular and the temperature control ducts 12, 13 each have a circular cross-sectional basic shape. The catheter tubing 10 also has a circular cross-sectional outer contour.

[0052] The inner lumens 11, 12, 13 are separated from one another by the material of the catheter tubing 10. The catheter tubing 10 is preferably formed from a single material in one piece.

[0053] To increase the flexural stiffness of the catheter tubing 10, at least one of the inner lumens 11, 12, 13 is provided with a reinforcement 20. In the exemplary embodiment according to FIG. 1, the reinforcement 20 is formed by structuring.

[0054] The structuring is formed as a longitudinal grooved contour extending over the inside circumference of the through-duct 11. In cross section, the through-duct therefore has a gear-like cross sectional inner contour. The basic shape of the cross section of the through-duct 11 is still circular, however.

[0055] The longitudinal grooves 21 preferably extend over the total length of the through-duct 11. The distance between the individual longitudinal grooves in the circumferential direction of the inside circumference of the through-duct 11 is preferably regular.

[0056] FIG. 2 shows an alternative exemplary embodiment, wherein the through-lumen 11 is provided with a reinforcement 20, which is designed as a separate material layer. In concrete terms it is provided that an additional material, which acts as the reinforcement 20, is arranged over the inside circumference of the through-lumen 20. The additional material is different from the material of the catheter tubing 10. In particular the additional material of the reinforcement 20 is preferably flexurally strong. In particular the material of the reinforcement 20 may have a greater strength than the material of the catheter tubing 10.

[0057] The exemplary embodiment according to FIG. 3 differs from the embodiment according to FIG. 2 in that in addition to the through-duct 11, the temperature control ducts 12, 13 are also provided with a reinforcement 20. It is possible in general to provide for at least one of the inner lumens 11, 12, 13 to be furnished with a reinforcement 20. Two or more inner lumens 11, 12, 13 may also be provided with the reinforcement 20.

[0058] It is possible for the wall thickness of the reinforcement to be of a dimension such that the reinforcements 20 which are associated with different inner lumens 11, 12, 13 come in contact with one another. In other words, it is possible to provide that the individual inner lumens 11, 12, 13, in particular at least two inner lumens 11, 12, 13, are separated from one another by only the reinforcement 20. In this case, there is no separation by the material of the catheter tubing 10.

[0059] The exemplary embodiment according to FIG. 4 is based on the exemplary embodiment according to FIG. 3 and shows a catheter tubing 10 having three inner lumens 11, 12, 13, wherein inner lumens designed as temperature control ducts 12, 13 are provided with a reinforcement 20. A third inner lumen designed as a through-duct 11 also has a reinforcement 20.

[0060] The reinforcement 20 of the through-duct 11 differs from the reinforcements 20 arranged in the temperature control ducts 12, 13. In particular the reinforcement 20 of the through-duct 11 is designed in multiple layers.

[0061] Therefore, an inner layer 20a, which preferably comprises a friction-reducing material, is provided. In concrete terms, a plastic material can be used for the inner layer 20a. PTFE, FEP or HDPE is preferred.

[0062] An outer layer 20c, preferably formed by a thermoplastic polymer, is provided. The outer layer 20c is directly adjacent to the inside circumferential surface of the through-duct 11.

[0063] A middle layer 20b is arranged between the outer layer 20c and the inner layer 20a. The middle layer 20b is preferably formed by a metallic mesh structure, in particular a metallic woven mesh. Alternatively it is possible to provide for the middle layer 20b to comprise a metallic winding, for example, a coiling.

[0064] Instead of a metal, the middle layer may also comprise a plastic material. To this extent polymer fibers are preferred to form the winding or the mesh. In general the wires or fibers forming the mesh or the winding may be embodied as round wires and/or round fibers or as flat wires and/or flat fibers. In all three cases, the fibers may each be formed by multifilament wires.

[0065] The reinforcement 20 arranged in the temperature control ducts 12, 13 preferably comprises a polyimide material. In particular, polyimide tubings inserted into the temperature control ducts 12, 13 may be provided. The polyimide tubings are then preferably arranged in such a way that they are fixedly in contact with the inside circumference of the temperature control ducts 12, 13. As an alternative to the polyimide material, HDPE or PA may also be used as the material for the reinforcement 20.

[0066] For all embodiments of the medical catheter it is true that a thermoplastic material is preferably used as the material for the catheter tubing 10. For example, polyether block amide having a Shore hardness of at least 35 D, in particular at least 40 D, in particular at least 50 D, in particular at least 63 D, in particular at least 70 D, in particular at least 72 D may be used. The material of the catheter tubing 10 may be designed so that the Shore hardness increases from the distal catheter tip to the proximal shaft end of the catheter tubing. PA may also be used as the material for the catheter tubing 10 as an alternative to polyether block amide.

[0067] The temperature control ducts 12, 13 are preferably provided with a reinforcement made of PEEK, polyamide and/or nylon and/or polyimide. It is possible to provide that the reinforcement 20 of the temperature control ducts 12, 13 is designed in multiple layers. In particular the reinforcement 20 of the temperature control ducts 12, 13 may have additional stiffening due to a mesh and/or a wire winding.

[0068] The through-lumen 11 preferably has a reinforcement 20 formed by a thermoplastic material which is different from the material of the catheter tubing 10. The material of the reinforcement 20 can be differentiated from the material of the catheter tubing 10 in particular in the composition of the material and/or the Shore hardness. The reinforcement 20 of the through-duct 11 has a material thickness between 50 m and 100 m.

[0069] The reinforcement 20 may comprise additional stiffening by means of a mesh as illustrated in FIG. 4. The mesh preferably has round wires, wherein round wires having a cross-sectional diameter of at most 51 m, in particular at most 40 m, in particular at most 26 m are used. When using flat wires, it is preferable for the flat wires to have a height of at most 51 m and a width of at most 130 m. Such wire dimensions may also be used for a winding, in particular a coil-type winding.

[0070] Preferred materials for the wires of the mesh and/or the winding include stainless steel or a nickel-titanium alloy.

[0071] The reinforcement 20, which is constructed in multiple layers, as illustrated in FIG. 4 as an example, preferably has a total thickness between 30 m and 100 m, in particular between 40 m and 50 m, in particular between 50 m and 80 m.

[0072] The through-lumen 11 is preferably of such dimensions that catheters and/or medical instruments in a size of 4 French, in particular 5 French, preferably 6 French, can be passed through it. In other words, the inside diameter of the through-lumen 11 having the reinforcement 20 is preferably at least 1.5 mm, in particular at least 1.8 mm, in particular at least 2.15 mm. In concrete terms, it is possible to provide for the through-lumen 11 to have an inside diameter in the range between 1.5 mm and 1.6 mm, in particular in the range from 1.8 mm to 1.9 mm, in particular in the range of 2.15 mm to 2.25 mm.

[0073] The temperature control ducts preferably have an inside diameter of at least 0.4 mm, in particular at least 0.6 mm, in particular at least 0.8 mm. The inside diameter of the temperature control ducts 12, 13 preferably amounts to at most 1.6 mm, in particular at most 1.4 mm, in particular at most 1.2 mm. It is particularly preferred if the temperature control ducts 12, 13 have an inside diameter of 1 mm.

[0074] The temperature control ducts 12, 13 preferably have a circular cross section. However, it is also possible for the temperature control ducts 12, 13 to have an oval, kidney-shaped or lung-shaped cross section.

[0075] The accompanying drawings show exemplary embodiments of the invention in which the catheter tubing 10 comprises three inner lumens 11, 12, 13. It is conceivable for more than three inner lumens 11, 12, 13 to be present. In particular at least one fourth inflation duct, which is connected to an inflatable balloon at the catheter tip, may be provided. The balloon is preferably designed as an occlusion balloon and makes it possible to close off a blood vessel. A fluid, for example, a gas or a liquid, can be transported through the inflation duct to the occlusion balloon, which results in expansion of the occlusion balloon.

[0076] Furthermore, in preferred exemplary embodiments of the catheter, it is possible to provide that a temperature sensor is arranged in the distal section of the catheter tubing 10, in particular at the catheter tip. The temperature sensor can be used to measure the blood temperature, so that the actual effect of the hypothermia can be monitored. Furthermore, a pressure sensor for the blood pressure measurement may be provided in a distal shaft section of the catheter tubing 10, in particular at the catheter tip. Other sensors, for example, a flow sensor are also conceivable.

[0077] With the arrangement of sensors in a distal shaft section of the catheter tubing 10, it is preferably provided that when the catheter tubing 10 has an additional lumen, it has in particular a cable duct for advancing electrical lines to the sensors.

[0078] Furthermore, a hydrophilic coating may be applied to the outside circumference of the catheter tubing 10. This improves the navigability of the catheter tubing 10 and/or of the catheter as a whole into a blood vessel. Furthermore, the hydrophilic coating, inasmuch as it is applied to a temperature control balloon, can improve the thermal efficacy of the hypothermia treatment. In particular, a heat exchange between the temperature control balloon and the surrounding blood is improved by the hydrophilic coating.

[0079] The material of the catheter tubing 10 can also be mixed with radiopaque and/or biocompatible powder. Such a powder can be introduced into the material of the catheter tubing 10 in particular. For example, approx. 10 wt % to 20 wt % of the material for the catheter tubing 10 may be formed by such a radiopaque and/or biocompatible powder. This improves the radiopacity of the catheter tubing 10 in particular. For this purpose, materials such as barium sulfate, bismuth trioxide, bismuth carbonate, zirconium, tungsten and/or tantalum are suitable in particular.

[0080] FIGS. 5a-c each show a longitudinal sectional view, a side view and a frontal view of a catheter according to the invention in another exemplary embodiment. The catheter tubing 10 has three inner lumens 11, 12, 13. Two inner lumens 12, 13 are designed as temperature control ducts 12, 13. The third inner lumen forms a through-duct 11. The inner lumens 11, 12, 13 are separated from one another by the material 10a of the catheter tubing. The material 10a of the catheter tubing may preferably have a thermoplastic elastomer such as PEBA or polyurethane.

[0081] Each of the inner lumens 11, 12, 13 has a reinforcement 20. The reinforcement 20 may be designed as a separate material layer. The additional material may be different from the material 10a of the catheter tubing. For example, the reinforcement 20 may be formed of a plastic. For example, the reinforcement 20 has a friction-reducing material. The reinforcement 20 may preferably be formed from a plurality of layers, in particular three layers. The interior layer and/or the layer adjacent to the inner lumen may comprise a plastic of a friction-reducing material, in particular fluoropolymer, PTFE or FEB. The layer in the middle may preferably be formed from a material reinforcement. For example, the material reinforcement may be braided or may have a coil. The exterior layer may preferably comprise a thermoplastic elastomer such as PEBA or polyurethane. Thus the exterior layer of the reinforcement 20 may also comprise the same material as the material of the catheter tubing 10a.

[0082] The catheter has a proximal extension region 33 and a distal extension region 34. The distal extension region 34 may have a length of 10 mm to 100 mm, in particular of 20 mm to 80 mm, in particular of 30 mm to 70 mm, preferably of 50 mm. The outside diameter of the catheter may amount to 3 mm in particular in the distal extension region 34. Thus the catheter may have an outside diameter of 9 French in particular in the distal extension region 34. The proximal extension region 33 may have a length of 10 mm to 100 mm, in particular of 20 mm to 80 mm, in particular of 30 mm to 70 mm, preferably of 50 mm.

[0083] In addition, the catheter has a middle region 35, arranged between the distal extension region 34 and the proximal extension region 33. The outside diameter of the catheter in the middle region 35 may be 2 mm to 5 mm, in particular 2.5 mm to 4.0 mm, in particular 3.5 mm. Thus the catheter may have an outside diameter of 11 French, in particular in the middle region 35. The entire shaft region of the catheter may preferably be of such dimensions that catheters and/or medical instruments with a size of 4 French, in particular 5 French, preferably 6 French, can be passed through it. The catheter may in general have a total length of 70 cm to 120 cm, in particular of 80 cm to 110 cm, preferably of 90 cm.

[0084] In the distal extension region 34, the reinforcement 20 of the through-duct 11 protrudes in sections beyond the catheter tubing 10. In other words, the reinforcement 20 of the through-duct 11 in the distal extension region 34 of the catheter, for example, is not surrounded by the material 10a of the catheter tubing. The outside diameter of the catheter tubing 10 is then reduced in the distal extension region 34. The reinforcement 20 forms an extension of the catheter tubing 10 in the distal extension region 34.

[0085] In addition, an additional distal reinforcement 31 is arranged in the distal extension region 34. Then the distal reinforcement 31, as can be seen in FIG. 5a, is arranged as an additional layer on the reinforcement 20 of the through-duct 11. For example, the reinforcement 20 of the through-duct 11 may be formed as a plastic layer. The distal reinforcement 31 may also comprise, for example, a plastic, in particular a plastic design to be flexible. For example, the reinforcement 31 may comprise a plastic having a lower modulus of elasticity and/or a lower hardness than the material of the catheter tubing 10a. The reinforcement 31 may preferably comprise a thermoplastic elastomer, such as PEBA or polyurethane.

[0086] In the proximal extension region 33, the reinforcements 20 of the inner lumens 11, 12, 13 protrude beyond the catheter tubing in some sections. In other words, the reinforcements 20 of the inner lumens 11, 12, 13 are not surrounded by the material of the catheter tubing 10a in the proximal extension region 33 of the catheter. The inner lumens 11, 12, 13 run independently of one another. Thus the outside diameter of the catheter may advantageously also be reduced in a proximal region. Furthermore, a facilitated connecting, for example, of Luer connections to be attached may be achieved due to the independence of the inner lumens 11, 12, 13 of one another.

[0087] For example, two balloons 30 are arranged on the outside circumference of the catheter tubing 10. The balloons 30 are arranged serially on the catheter tubing 10. It is particular advantageous if the balloons 30 are fluidically connected to the temperature control ducts 12, 13 such that they can be exposed serially to the oncoming flow.

LIST OF REFERENCE NUMERALS

[0088] 10 catheter tubing [0089] 10a material of the catheter tubing [0090] 11 through-duct [0091] 12, 13 temperature control duct [0092] 20 reinforcement [0093] 20a inner layer [0094] 20b middle layer [0095] 20c outer layer [0096] 30 balloon [0097] 31 distal reinforcement [0098] 32 proximal reinforcement [0099] 33 proximal extension region [0100] 34 distal extension region [0101] 35 central region