A 6-hole reinforced hard film catheter and a preparation process thereof

Abstract

The application belongs to the technical field of medical anesthetic apparatus, and provides a 6-hole reinforced epidural catheter and a preparation process thereof, wherein the 6-hole reinforced epidural catheter comprises a catheter main body, a reinforcing assembly, a medicine outlet assembly, an anti-injury tip, a scale mark and a connecting joint; the catheter main body is a hollow tubular structure and is made of hydrophilic modified medical polyurethane material; the catheter main body is sequentially divided into an insertion section, a transition section and a connecting section along an axial direction; the reinforcing assembly is embedded in the pipe wall of the catheter main body and penetrates through the whole length of the catheter main body; and the reinforcing assembly is a composite structure composed of double helical steel wires and a fiber reinforced layer; the application improves the catheter's resistance to folding and pulling and the uniformity of medicine outlet, reduces the risk of catheterization injury, is accurate and convenient to operate, and is suitable for industrialized production, and is suitable for epidural anesthesia and postoperative analgesia.

Description

Technical Field

[0001] This invention belongs to the field of medical anesthesia device technology, and particularly relates to a 6-hole reinforced dural catheter and its preparation process. Background Technology

[0002] The dural catheter is the core instrument in epidural anesthesia, and its structural design directly affects the anesthetic blockade effect, operational safety, and patient prognosis.

[0003] Currently, the dural catheters commonly used in clinical practice have unreasonable structural design and insufficient resistance to bending and tension, which can easily lead to problems such as bending, breakage, and separation of the tube wall from the steel wire, increasing the difficulty of tube removal and the risk of foreign body residue in the spinal canal;

[0004] The limited number of drug outlet holes, their concentrated location, and the flawed hole design can easily lead to problems such as uneven drug diffusion, incomplete blockage, rapid drug ejection that irritates tissues, and easy wear and leakage of the hole walls, resulting in poor stability of the anesthetic effect.

[0005] The catheter tip has insufficient protection against damage and no surface modification treatment, making it easy to puncture the dura mater and blood vessels. Long-term indwelling can easily cause adhesion to the spinal canal mucosa, leading to various complications.

[0006] Meanwhile, the catheter markings are unclear, insertion is difficult, and the connector is prone to falling off, resulting in insufficient ease of operation and precision, making it unsuitable for clinical scenarios such as complex spinal canal anatomy and long-term indwelling.

[0007] In addition, existing manufacturing processes are unable to achieve a tight bond between the composite reinforcement structure and the catheter wall, which can easily lead to problems such as loosening and peeling of the steel wire. Furthermore, the processing precision of the drug outlet hole is insufficient, making it impossible to accurately control the hole shape parameters. This results in low product yield and poor performance consistency, making it difficult to meet the needs of large-scale industrial production.

[0008] Therefore, a 6-hole reinforced dura mater catheter and its manufacturing process are needed to solve the above problems. Summary of the Invention

[0009] The purpose of this invention is to provide a 6-hole reinforced dura mater catheter and its manufacturing process to solve the problems mentioned in the background art.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a 6-hole reinforced dura mater catheter, comprising a catheter body, a reinforcing component, a drug delivery component, an anti-damage tip, graduation marks, and a connecting connector; the catheter body is a hollow tubular structure made of hydrophilic modified medical polyurethane material, and is sequentially divided into an insertion section, a transition section, and a connecting section along the axial direction; the reinforcing component is embedded in the wall of the catheter body and extends through the entire length of the catheter body, and is a composite structure composed of double-helix steel wire and fiber reinforcement layer; the drug delivery component includes 6 drug delivery holes, all of which are located in the insertion section of the catheter body, and are distributed symmetrically in two groups on both sides of the insertion section, with 3 drug delivery holes in each group evenly arranged along the axial direction of the catheter, and the drug delivery holes are funnel-shaped; the anti-damage tip is an integrally molded hemispherical structure made of medical soft silicone, and is seamlessly connected to the insertion end of the catheter body; the graduation marks are set on the outer surface of the catheter body; the connecting connector is fixedly connected to the connecting section of the catheter body.

[0011] A further technical solution involves using 316L medical-grade stainless steel wire with a diameter of 0.05-0.08 mm. The two wires are spirally wound in opposite directions. The spiral pitch of the double-helix wire is segmented along the catheter axis, with the insertion section having a spiral pitch of 1.0-1.5 mm, the transition section having a spiral pitch of 0.8-1.0 mm, and the connecting section having a spiral pitch of 0.5-0.8 mm. This structure optimizes flexibility and rigidity according to the stress characteristics of different sections of the catheter. The insertion section ensures flexibility to avoid tissue damage, the transition section balances flexibility and rigidity for easy operation, and the connecting section enhances tensile strength to prevent traction breakage. Simultaneously, the reverse double-helix design prevents wire torsion deformation and improves the catheter's resistance to bending and torsion.

[0012] A further technical solution is that the fiber reinforcement layer is located between the double helical steel wire and the inner wall of the catheter body, and is woven from medical-grade polyarylate fiber with a weaving density of 80-90% and a fiber diameter of 0.02-0.03mm. This structure can form a dense reinforcement network, further enhancing the tear resistance and wear resistance of the catheter wall, while ensuring that the helical steel wire is tightly bonded to the tube wall, preventing the steel wire from loosening or peeling, and without affecting the overall flexibility of the catheter.

[0013] In a further technical solution, in the drug dispensing assembly, the first group of drug dispensing holes is 1.0 cm away from the top of the anti-damage device, the second group of drug dispensing holes is 1.0 cm away from the first group of drug dispensing holes, and the included angle between the two groups of drug dispensing holes is 180°; the inlet diameter of the drug dispensing hole is 0.2-0.25 mm, the outlet diameter is 0.3-0.35 mm, the edge of the outlet end is provided with a rounded chamfer, and the inner side of the hole wall is provided with a medical-grade polytetrafluoroethylene wear-resistant coating; the symmetrical staggered hole design can ensure that at least 4 drug dispensing holes can still dispense drugs normally when the catheter is biased, avoiding incomplete anesthesia blockage caused by blockage; the trumpet-shaped hole can slow down the speed of drug spraying, avoiding stimulation of nerves and blood vessels in the spinal canal; the wear-resistant coating and rounded chamfer can improve the wear resistance and anti-blockage performance of the hole wall, avoiding leakage problems during long-term drug administration.

[0014] A further technical solution is that the diameter of the anti-damage tip is 1.2-1.5mm, slightly larger than the outer diameter of the catheter body. The anti-damage tip and the catheter body are seamlessly connected by a thermal fusion process. The tip has a flow channel that communicates with the hollow channel of the catheter body. The surface of the hemispherical soft silicone structure is smooth and round, which can effectively avoid puncturing the dura mater and blood vessels in the spinal canal during the insertion process. The seamless connection design has no steps or gaps, which can avoid drug leakage and bacterial growth. The internal flow channel can assist the diffusion of drug and at the same time prevent the tip from blocking the catheter channel.

[0015] A further technical solution involves printing the scale markings with medical-grade alcohol-resistant ink. Starting from the top to prevent damage, one scale line is set every 1cm, and a thickened scale line is set every 5cm with corresponding values. A red positioning mark is provided at the end of the insertion section. The alcohol-resistant ink printing is not easy to peel off, and the clear scale and numerical markings can help doctors accurately judge the insertion depth. The red positioning mark can indicate the safe insertion depth, avoiding insertion that is too deep or too shallow, and reducing the difficulty of the catheter insertion operation.

[0016] A further technical solution is that the connector is made of medical-grade polycarbonate material, with a medical-grade nitrile rubber sealing ring inside and anti-slip texture on the outside. The end of the connector is a standard Luer interface. The double helix steel wire and fiber reinforcement layer of the reinforcing component extend into the interior of the connector and are fixed with medical-grade epoxy adhesive. The sealing ring ensures a tight connection without leakage, the anti-slip texture facilitates the doctor's grip and operation, and the standard Luer interface is compatible with commonly used clinical syringes, analgesic pumps and other drug delivery devices, making it highly versatile. The internal fixation of the reinforcing component and the connector can prevent the catheter from falling off or the reinforcing structure from peeling off when pulled.

[0017] A further technical solution is that the main body of the catheter is 50-80cm in length, with an outer diameter of 0.8-1.2mm, an inner diameter of 0.5-0.8mm, and a wall thickness of 0.15-0.2mm. This size design can be adapted to the spinal canal anatomy of different patients such as adults, the elderly, and children. The uniform wall thickness can ensure the overall structural strength of the catheter, while ensuring that the catheter is lightweight and easy to operate, and can be smoothly inserted into the spinal canal through an epidural puncture needle.

[0018] A manufacturing process for a 6-hole reinforced dural catheter, applicable to any of the aforementioned 6-hole reinforced dural catheters, includes the following steps:

[0019] S1. Enhance component fabrication;

[0020] S2, The main body of the conduit is co-extruded;

[0021] S3. Machining of the drug outlet hole;

[0022] S4, Damage-resistant top connection;

[0023] S5. Scale printing and connector assembly;

[0024] S6. Aseptic processing and testing.

[0025] In a further technical solution, in step S2, the heating temperature of the extruder is 180-200℃; in step S6, the parameters for high-pressure steam sterilization are 121℃ and 30min, and the performance tests include air tightness, pressure resistance, and uniformity of drug dispensing.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] This invention, through a composite reinforcement structure of "double helical steel wire + fiber reinforcement layer" combined with a segmented optimized helical pitch design, achieves the best balance between flexibility and rigidity in each segment of the catheter, completely solving the problems of easy kinking, breakage, and loosening and peeling of steel wire in existing catheters. It significantly improves the structural stability of the catheter, reduces the risk of foreign body residue in the spinal canal and difficulty in catheter removal, and greatly improves the safety of anesthesia operations.

[0028] This invention, through the design of 6 symmetrically staggered trumpet-shaped drug outlet holes, avoids the problem of drug outlet blockage when the catheter is biased, achieves uniform and even diffusion of drug solution, improves the success rate and stability of anesthesia block, reduces the occurrence of unilateral anesthesia and incomplete block, and at the same time avoids the high-speed impact of drug solution on tissues, reducing the incidence of adverse reactions. The wear-resistant coating on the hole wall improves the durability of the catheter and can meet the drug delivery needs of long-term postoperative analgesia.

[0029] This invention, through the design of a hemispherical soft silicone anti-damage tip and a catheter body made of hydrophilic modified material, effectively avoids damage to the dura mater and spinal canal blood vessels during insertion, reduces the incidence of complications such as cerebrospinal fluid leakage and epidural hematoma, and at the same time reduces the adhesion between the catheter and the spinal canal mucosa during long-term indwelling, making it less likely to damage the mucosa when removing the catheter, thus improving patient comfort and safety.

[0030] This invention improves the accuracy and convenience of catheter insertion through clear scale markings, positioning marks, and a standard Luer interface design. It can assist doctors in quickly and accurately controlling the insertion depth, reduce the difficulty of operation, and is suitable for anesthesiologists with insufficient experience. At the same time, it can be quickly adapted to various clinical drug delivery devices, making it highly versatile and widely applicable.

[0031] This invention, along with its supporting manufacturing process, employs a co-extrusion molding process to achieve integrated molding of the reinforcing components and the catheter body, ensuring a tight bond between the composite structure and the tube wall without loosening or peeling. Laser drilling is used to precisely process drug-eluting holes, guaranteeing the accuracy and consistency of hole position and diameter, thus improving product yield. The entire process is simple, using industry-standard equipment, eliminating the need for additional special production lines, and is suitable for large-scale industrial production. It also considers the product's economic efficiency and practicality, facilitating large-scale clinical application.

[0032] To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0033] Figure 1 This is a frontal structural diagram of the present invention;

[0034] Figure 2 This is a three-dimensional structural schematic diagram of the sealing ring of the present invention;

[0035] Figure 3 This is a partial three-dimensional structural diagram of the reinforcing component of the present invention;

[0036] Figure 4 This is a three-dimensional structural diagram of the thickened scale lines of the present invention;

[0037] Figure 5 This is a three-dimensional structural diagram of the anti-damage top of the present invention.

[0038] In the diagram: 1. Catheter body; 11. Insertion section; 12. Transition section; 13. Connecting section; 2. Reinforcing component; 21. Double helical steel wire; 22. Fiber reinforcement layer; 3. Drug delivery component; 31. Drug delivery port; 4. Damage-resistant tip; 5. Scale markings; 51. Scale line; 52. Thickened scale line; 53. Red positioning mark; 6. Connecting connector; 61. Sealing ring; 62. Anti-slip texture; 63. Luer interface. Detailed Implementation

[0039] The present invention will be further described below with reference to embodiments.

[0040] The following embodiments are used to illustrate the present invention, but should not be used to limit the scope of protection of the present invention. The conditions in the embodiments can be further adjusted according to specific conditions, and simple improvements to the method of the present invention under the premise of the concept of the present invention are all within the scope of protection claimed by the present invention.

[0041] Please see Figure 1-5 The present invention provides a 6-hole reinforced dura mater catheter, comprising a catheter body 1, a reinforcing component 2, a drug delivery component 3, a damage-resistant tip 4, a scale mark 5, and a connecting connector 6.

[0042] In this embodiment, the catheter body 1 is a hollow tubular structure made of hydrophilic modified medical polyurethane material. The catheter body 1 is divided into an insertion section 11, a transition section 12 and a connecting section 13 along the axial direction.

[0043] Specifically, the main body of the catheter 1 is 50-80cm in length, with an outer diameter of 0.8-1.2mm, an inner diameter of 0.5-0.8mm, and a wall thickness of 0.15-0.2mm. The material has a smooth surface, excellent tissue compatibility, and good flexibility, elasticity, and wear resistance, which can prevent long-term indwelling and adhesion to the spinal canal mucosa.

[0044] In this embodiment, the reinforcing component 2 is embedded in the wall of the catheter body 1 and runs through the entire length of the catheter body 1. The reinforcing component 2 is a composite structure composed of a double helical steel wire 21 and a fiber reinforcement layer 22.

[0045] Specifically, the double helical steel wire 21 is made of 316L medical-grade stainless steel wire with a wire diameter of 0.05-0.08 mm. The two wires are spirally wound in opposite directions. The helical pitch of the double helical steel wire 21 is segmented along the catheter axis, with the insertion section 11 having a helical pitch of 1.0-1.5 mm, the transition section 12 having a helical pitch of 0.8-1.0 mm, and the connecting section 13 having a helical pitch of 0.5-0.8 mm. The fiber reinforcement layer 22 is located between the double helical steel wire 21 and the inner wall of the catheter body 1. It is made of medical-grade polyarylate fiber with a weaving density of 80-90% and a fiber diameter of 0.02-0.03 mm.

[0046] In this embodiment, the drug dispensing component 3 includes 6 drug dispensing holes 31, all of which are located in the insertion section 11 of the catheter body 1. The 6 drug dispensing holes 31 are divided into two groups and symmetrically staggered on both sides of the insertion section 11 of the catheter. Each group has 3 drug dispensing holes 31 evenly arranged along the axial direction of the catheter. The drug dispensing holes 31 have a trumpet-shaped structure.

[0047] Specifically, the first set of drug outlet holes 31 is 41.0 cm away from the top of the anti-damage device, and the second set of drug outlet holes 31 is 11.0 cm away from the first set of drug outlet holes 31. The included angle between the two sets of drug outlet holes 31 is 180°. The inlet diameter of the drug outlet hole 31 is 0.2-0.25 mm, the outlet diameter is 0.3-0.35 mm, the edge of the outlet end is provided with a smooth chamfer with a chamfer radius of 0.05 mm, and the inner side of the hole wall is provided with a medical-grade polytetrafluoroethylene wear-resistant coating with a thickness of 0.01 mm.

[0048] In this embodiment, the anti-damage tip 4 is an integrally molded hemispherical structure made of medical soft silicone, and the anti-damage tip 4 is seamlessly connected to the insertion end of the catheter body 1.

[0049] Specifically, the diameter of the anti-damage tip 4 is 1.2-1.5mm, which is slightly larger than the outer diameter of the conduit body 1. The anti-damage tip 4 is seamlessly connected to the conduit body 1 through a thermal fusion process. Its interior is provided with a guide groove that communicates with the hollow channel of the conduit body 1. The surface is smooth and rounded without sharp edges.

[0050] In this embodiment, the scale mark 5 is provided on the outer surface of the catheter body 1.

[0051] Specifically, the scale markings 5 ​​are printed with medical-grade alcohol-resistant ink. Starting from the damage-resistant top 4, one scale line 51 is set every 1cm, and one thickened scale line 52 is set every 5cm with corresponding values. A red positioning mark 53 is provided at the end of the insertion section 11.

[0052] In this embodiment, the connecting joint 6 is fixedly connected to the connecting section 13 of the catheter body 1.

[0053] Specifically, the connector 6 is made of medical-grade polycarbonate material, with a medical-grade nitrile rubber sealing ring 61 inside and anti-slip texture 62 on the outside. The end of the connector is a standard Luer interface 63. The double helical steel wire 21 and fiber reinforcement layer 22 of the reinforcing component 2 extend into the interior of the connector 6 and are fixed by medical-grade epoxy adhesive.

[0054] A fabrication process for a 6-hole reinforced dural catheter, applied to the 6-hole reinforced dural catheter of the above embodiment, includes the following steps:

[0055] S1. Preparation of reinforced component 2;

[0056] S2, the conduit body 1 is co-extruded;

[0057] S3, machining of the drug outlet hole 31;

[0058] S4, Anti-damage top 4 connection;

[0059] S5. Scale printing and connector assembly;

[0060] S6. Aseptic processing and testing.

[0061] In this embodiment, step S1 specifically involves: using a spring winding machine to wind 316L medical stainless steel wire into a double helical steel wire 21, adjusting the winding speed according to the catheter segment pitch requirements; and using a braiding machine to braid polyarylate fibers into a fiber reinforcement layer 22 for later use.

[0062] Specifically, during the winding process, the rotation speed of the winding machine is adjusted according to the pitch requirements of the insertion section 11, transition section 12, and connecting section 13 to ensure accurate spiral pitch. The weaving density of the fiber reinforcement layer 22 is precisely controlled according to the design requirements to ensure uniform weaving without broken filaments.

[0063] In this embodiment, step S2 specifically involves: adding hydrophilic modified polyurethane material to an extruder and heating it to a molten state; simultaneously, feeding the double helical steel wire 21 and fiber reinforcement layer 22 into a co-extrusion die and co-extruding them with the molten polyurethane material to form the conduit body 1; and cooling and shaping it in a cooling water tank to ensure that the reinforcing component 2 is tightly bonded to the pipe wall.

[0064] Specifically, the extruder heating temperature is 180-200℃, and the cooling water tank temperature is controlled at 20-30℃ to ensure that the main body 1 of the guide tube is unbiased and undeformed after cooling and shaping, and that the reinforcing component 2 is tightly bonded to the tube wall without loosening.

[0065] In this embodiment, step S3 specifically involves: using a laser drilling machine to process six trumpet-shaped drug outlet holes 31 in the catheter insertion section 11, precisely controlling the hole position and diameter, then chamfering the outlet end of the drug outlet hole 31, spraying a polytetrafluoroethylene wear-resistant coating, and drying and curing.

[0066] Specifically, the power and pulse frequency of laser drilling are adjusted according to the requirements of the guide tube wall thickness and hole diameter to ensure that the hole shape is regular, the edges are smooth, the wear-resistant coating is sprayed evenly, and there is no peeling or cracking after drying.

[0067] In this embodiment, step S4 specifically involves heating medical soft silicone to a molten state, seamlessly connecting it to the top of the catheter insertion end through a heat fusion process, forming a hemispherical shape, and then trimming the surface after cooling to ensure a smooth and rounded appearance.

[0068] Specifically, the heat fusion process uses injection molding to ensure that there are no steps, gaps, or burrs at the joint. After cooling, the surface smoothness is further improved through polishing to avoid sharp edges.

[0069] In this embodiment, step S5 specifically involves: printing scale marks 5 and positioning marks on the surface of the conduit using screen printing technology, and drying and curing them; fixing the connecting joint 6 to the conduit connecting section 13 with epoxy adhesive, installing the sealing ring 61, and completing the overall assembly.

[0070] Specifically, the printing uses medical-grade alcohol-resistant ink, and the ink adhesion meets the standards after drying, with no peeling or blurring. The epoxy adhesive is fully cured at room temperature, ensuring that the joint connection is firm and does not fall off.

[0071] In this embodiment, step S6 specifically involves: sterilizing the assembled catheter with high-pressure steam, then performing performance testing, and packaging and storing it after it passes the test.

[0072] Specifically, the parameters for high-pressure steam sterilization are 121℃ for 30 minutes. Performance testing includes items such as airtightness, pressure resistance, drug dispensing uniformity, and dimensional accuracy. Only after all items pass the test can the product be packaged and stored.

[0073] Example 1: 6-hole reinforced dural catheter (adult type)

[0074] This embodiment is consistent with the overall technical solution described above, and the specific parameters are as follows:

[0075] Catheter body 1: Made of hydrophilic modified medical PU material, with a total length of 70cm, an outer diameter of 1.0mm, an inner diameter of 0.6mm, and a wall thickness of 0.2mm; insertion section 11 is 10cm long, transition section 12 is 25cm long, and connecting section 13 is 35cm long.

[0076] Reinforcing component 2: The double helical steel wire 21 is made of 316L medical stainless steel wire with a diameter of 0.06mm, and the two steel wires are wound in opposite spirals; the insertion section 11 has a helical pitch of 1.2mm, the transition section 12 is 1.0mm, and the connecting section is 130.6mm; the fiber reinforcement layer 22 is made of polyarylate fiber with a weaving density of 85% and a fiber diameter of 0.025mm; the reinforcing component 2 and the connecting joint 6 are fixed with epoxy glue.

[0077] Drug dispensing component 3: Six drug dispensing holes 31 are set in the insertion section 11, symmetrically distributed in two groups (with an included angle of 180°), with three holes in each group; the first group is 1.0 cm away from the top, and the second group is 1.0 cm away from the first group; the drug dispensing holes (31) are trumpet-shaped, with an inlet diameter of 0.22 mm, an outlet diameter of 0.32 mm, an outlet chamfer radius of 0.05 mm, and a polytetrafluoroethylene wear-resistant coating (thickness of 0.01 mm) on the inner side of the hole wall.

[0078] Damage-resistant tip 4: Made of medical-grade soft silicone, hemispherical, 1.3mm in diameter, seamlessly heat-fused to the catheter body 1, with internal drainage grooves.

[0079] Scale markings 5 ​​and connecting connectors 6: One scale line 51 is set every 1cm, and one thickened scale line 52 is set every 5cm, with numerical values ​​marked; a red positioning mark 53 is set at the end of the insertion section 11 (12cm); the connecting connector 6 is made of PC material, with a standard Luer interface 63, an internal nitrile rubber sealing ring 61, and an external anti-slip texture 62.

[0080] Preparation process parameters:

[0081] Preparation of reinforcing component 2: The winding speed of the spring winding machine insertion section 11 is 80 r / min, the transition section 12 is 100 r / min, and the connecting section 13 is 120 r / min; the fiber reinforcement layer 22 has a weaving density of 85%.

[0082] The conduit body 1 is co-extruded: the extruder heating temperature is 190℃ and the cooling water tank temperature is 25℃.

[0083] Processing of the discharge hole 31: 8W UV laser drilling machine, 20kHz pulse frequency, and drying and curing of the wear-resistant coating at 120℃ for 30 minutes.

[0084] Damage-resistant top 4 connection: silicone melting temperature 160℃, integrally molded using injection molding thermal fusion process.

[0085] Scale printing and connector assembly: Ink is dried and cured at 100℃ for 15 minutes, and epoxy is cured at room temperature for 24 hours.

[0086] Aseptic treatment and testing: high-pressure steam sterilization at 121℃ for 30 minutes, followed by full performance testing.

[0087] Example 2: 6-hole reinforced dural catheter (pediatric type)

[0088] This embodiment is basically the same as Example 1 in terms of structure and preparation process, except that the following parameters are adjusted according to the anatomical characteristics of the pediatric spinal canal:

[0089] Catheter body 1: 50cm in total length, 0.8mm in outer diameter, 0.5mm in inner diameter, and 0.15mm in wall thickness; insertion section 11 is 8cm in length, transition section 12 is 20cm in length, and connecting section 13 is 22cm in length.

[0090] Reinforcing component 2: Double helical steel wire 21 with a diameter of 0.05mm, insertion section 11 with a helical pitch of 1.0mm, transition section 12 with a diameter of 0.8mm, and connecting section with a diameter of 130.5mm; fiber reinforcement layer 22 with a weaving density of 80% and a fiber diameter of 0.02mm.

[0091] Drug dispensing component 3: The inlet diameter of the drug dispensing hole 31 is 0.2 mm, and the outlet diameter is 0.3 mm. The hole position distribution is the same as in Example 1; the anti-damage tip 4 has a diameter of 1.2 mm, which is suitable for the spinal canal size of children.

[0092] Scale mark 5: One scale line 51 is set every 0.5cm, and one thickened scale line 52 is set every 2cm. A red positioning mark 53 is set at the end of the insertion section 11 (8cm away) to facilitate precise control of the insertion depth.

[0093] Process adjustments: The co-extrusion molding temperature was adjusted to 180℃, and the laser drilling power was adjusted to 6W to ensure that the thin-walled conduit was free from deformation and damage. The remaining process steps were the same as in Example 1.

[0094] Working principle and usage process of the present invention

[0095] The 6-hole reinforced dural catheter of the present invention achieves safe, precise, and efficient anesthesia administration through the synergistic cooperation of the segmented composite reinforcement component 2, the drug delivery component 3, and the damage-preventing tip 4. Its specific working principle and usage procedure are as follows:

[0096] Before use, check the overall integrity of the catheter, confirm that the scale markings 5 ​​are clear, the connector 6 is sealed properly, and the drug outlet 31 of the drug dispensing component 3 is not blocked. Connect the syringe through the standard Luer interface 63 of the connector 6, inject saline to confirm that the hollow channel of the catheter body 1 is unobstructed and leak-free, and complete the preoperative preparation.

[0097] During anesthesia, after completing the epidural puncture and confirming that the puncture needle has entered the epidural space, the anti-damage tip 4 of the catheter body 1 is oriented towards the patient's head or tail and inserted into the epidural space through the inner lumen of the puncture needle. During insertion, the large-pitch double-helix steel wire 21 of the insertion section 11 of the catheter body 1, combined with the soft hydrophilic modified polyurethane material, can naturally bend with the anatomical structure of the spinal canal and smoothly pass through narrow and deformed spinal canal spaces. The anti-damage tip 4 of the hemispherical soft silicone can smoothly push aside the tissues inside the spinal canal during advancement, avoiding puncture of the dura mater, blood vessels and nerves, and greatly reducing the risk of catheter placement injury.

[0098] During catheter placement, the depth of the catheter inserted into the epidural space can be accurately determined by the scale markings 5 ​​and red positioning marks 53 on the outer surface of the catheter body 1, avoiding placement that is too deep or too shallow. After the catheter is placed, the puncture needle is withdrawn and stably connected to the drug delivery device or analgesia pump through the connecting connector 6. The nitrile rubber sealing ring 61 inside the connector can prevent leakage during drug delivery. The double helix steel wire 21 and fiber reinforcement layer 22 of the reinforcing component 2 extend into the connecting connector 6 for fixation, which can prevent catheter dislodgement and structural damage caused by traction during and after the operation.

[0099] During drug administration, the anesthetic solution is delivered to the insertion segment 11 through the hollow channel of the catheter body 1, and is evenly sprayed out through the six symmetrically staggered trumpet-shaped drug outlets 31 of the drug outlet component 3. Even if the catheter is misaligned in the spinal canal, at least four drug outlets 31 can still deliver the drug normally, avoiding incomplete blockage caused by tissue blockage. The trumpet-shaped structure of the drug outlets 31 can slow down the speed of drug spraying, avoid the drug from impacting the dura mater and nerve roots at high speed, reduce adverse reactions such as pain and blood pressure fluctuations in patients, and allow the drug to diffuse evenly along the spinal canal axis to achieve a uniform anesthetic blockage effect across the entire segment. The onset of action is fast and the blockage effect is stable, eliminating the need for repeated drug administration. The polytetrafluoroethylene wear-resistant coating on the inner wall of the drug outlet 31 can withstand long-term infusion of analgesics containing particles, avoiding wear, leakage and blockage of the hole wall, and ensuring the continuity and stability of analgesia for 48-72 hours after surgery.

[0100] During catheter placement, the hydrophilic modified catheter body 1 has a smooth surface, making it less prone to adhesion to the spinal canal mucosa. The composite reinforcement structure formed by the double helical steel wire 21 of the reinforcing component 2 and the fiber reinforcement layer 22 can withstand repeated bending caused by changes in patient position, without kinking, breakage, or steel wire deformation, ensuring the stability of drug administration during placement. When removing the catheter, the small-pitch double helical steel wire 21 of the connecting segment 13 of the catheter body 1, combined with the fiber reinforcement layer 22, provides excellent tensile strength, avoiding traction breakage. At the same time, the smooth surface of the catheter body 1 allows for smooth removal without damaging the spinal canal mucosa, reducing the risk of difficult removal and foreign body residue.

[0101] The supporting manufacturing process of this invention achieves integrated bonding between the reinforcing component 2 and the tube wall of the catheter body 1 through co-extrusion molding, fundamentally solving the problem of loosening and peeling of the double helical steel wire 21; the laser drilling process precisely controls the position, diameter and shape of the drug outlet hole 31 of the drug outlet component 3, ensuring the consistency of product performance; the thermal fusion process achieves seamless connection between the damage-resistant tip 4 and the catheter body 1, avoiding the risk of drug leakage and bacterial growth. The entire process has strong controllability, high product yield, and is suitable for large-scale industrial production.

[0102] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A 6-hole reinforced dural catheter, characterized in that, It includes the catheter body (1), reinforcement components (2), drug delivery components (3), damage-resistant tip (4), graduation marks (5), and connection connector (6); The catheter body (1) is a hollow tubular structure made of hydrophilic modified medical polyurethane material. The catheter body (1) is divided into an insertion section (11), a transition section (12) and a connecting section (13) along the axial direction. The reinforcing component (2) is embedded in the wall of the catheter body (1) and runs through the entire length of the catheter body (1). The reinforcing component (2) is a composite structure composed of a double helical steel wire (21) and a fiber reinforcement layer (22). The drug dispensing assembly (3) includes 6 drug dispensing holes (31), all of which are located in the insertion section (11) of the catheter body (1). The 6 drug dispensing holes (31) are divided into two groups and symmetrically staggered on both sides of the catheter insertion section (11). Each group of 3 drug dispensing holes (31) are evenly arranged along the axial direction of the catheter. The drug dispensing holes (31) are funnel-shaped structures. The anti-damage tip (4) is an integrally molded hemispherical structure made of medical soft silicone. The anti-damage tip (4) is seamlessly connected to the insertion end of the catheter body (1). The scale markings (5) are provided on the outer surface of the catheter body (1); The connecting joint (6) is fixedly connected to the connecting section (13) of the catheter body (1).

2. The 6-hole reinforced dura mater catheter according to claim 1, characterized in that, The double helical steel wire (21) is made of 316L medical stainless steel wire with a wire diameter of 0.05-0.08mm. The two steel wires are spirally wound in opposite directions. The helical pitch of the double helical steel wire (21) is segmented along the axial direction of the catheter. The helical pitch of the insertion section (11) is 1.0-1.5mm, the helical pitch of the transition section (12) is 0.8-1.0mm, and the helical pitch of the connecting section (13) is 0.5-0.8mm.

3. The 6-hole reinforced dural catheter according to claim 1, characterized in that, The fiber reinforcement layer (22) is located between the double helical steel wire (21) and the inner wall of the catheter body (1), and is made of medical grade polyarylate fiber with a weaving density of 80-90% and a fiber diameter of 0.02-0.03 mm.

4. The 6-hole reinforced dural catheter according to claim 1, characterized in that, In the drug dispensing assembly (3), the first set of drug dispensing holes (31) is 1.0 cm away from the top of the anti-damage top (4), the second set of drug dispensing holes (31) is 1.0 cm away from the first set of drug dispensing holes (31), and the included angle between the two sets of drug dispensing holes (31) is 180°; the inlet diameter of the drug dispensing hole (31) is 0.2-0.25 mm, the outlet diameter is 0.3-0.35 mm, the edge of the outlet end is provided with a rounded chamfer, and the inner side of the hole wall is provided with a medical grade polytetrafluoroethylene wear-resistant coating.

5. The 6-hole reinforced dural catheter according to claim 1, characterized in that, The diameter of the anti-damage tip (4) is 1.2-1.5 mm, which is slightly larger than the outer diameter of the conduit body (1). The anti-damage tip (4) and the conduit body (1) are seamlessly connected by a thermal fusion process. The inside of the tip is provided with a guide groove that communicates with the hollow channel of the conduit body (1).

6. The 6-hole reinforced dural catheter according to claim 6, characterized in that, The scale markings (5) are printed with medical-grade alcohol-resistant ink. Starting from the top of the anti-damage top (4), one scale line (51) is set every 1cm, and one thickened scale line (52) is set every 5cm. The corresponding values ​​are marked. A red positioning mark (53) is provided at the end of the insertion section (11).

7. The 6-hole reinforced dura mater catheter according to claim 6, characterized in that, The connector (6) is made of medical grade polycarbonate material. The connector has a medical grade nitrile rubber sealing ring (61) inside and anti-slip texture (62) outside. The end of the connector is a standard Luer interface (63). The double helical steel wire (21) and fiber reinforcement layer (22) of the reinforcing component (2) extend into the connector (6) and are fixed by medical grade epoxy glue.

8. The 6-hole reinforced dural catheter according to claim 6, characterized in that, The main body of the catheter (1) has a total length of 50-80cm, an outer diameter of 0.8-1.2mm, an inner diameter of 0.5-0.8mm, and a wall thickness of 0.15-0.2mm.

9. A manufacturing process for a 6-hole reinforced dural catheter, applied to the 6-hole reinforced dural catheter according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Preparation of reinforced component (2); S2, the main body of the conduit (1) is co-extruded; S3, processing of the drug outlet hole (31); S4, Anti-damage top (4) connection; S5. Scale printing and connector assembly; S6. Aseptic processing and testing.

10. The manufacturing process of the 6-hole reinforced dura mater catheter according to claim 9, characterized in that, In step S2, the heating temperature of the extruder is 180-200℃; in step S6, the parameters for high-pressure steam sterilization are 121℃ and 30min, and the performance tests include air tightness, pressure resistance, and uniformity of drug dispensing.

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