Incision protection sleeve for medical engineering and production process thereof

Abstract

The invention discloses an incision protection sleeve for medical engineering and a production process thereof, the incision protection sleeve comprises an outer layer protection film and an inner layer protection film, the outer layer protection film is composed of a polytetrafluoroethylene base material and a nano-silver composite layer coated on the surface, the density of the nano-silver composite layer is 1.5-3.0 mg / cm, the thickness of the nano-silver composite layer is 0.1-0.3 mm, the diameter of hollow microspheres is 50-200 [mu] m, the wall thickness of the hollow microspheres is 5-15 [mu] m, and the filling rate of the hollow microspheres is 10-30% of the volume of a buffer ring; according to the material innovation, the PTFE-nano-silver composite layer gives consideration to antibacterial performance and durability, the collagen-silica gel buffer layer promotes tissue repair, the structure innovation is that magnetic fixation and a shape memory support achieve one-key type rapid installation, the operation time in an operation is shortened by more than 20%, the process innovation is that laser welding and plasma spraying technologies are combined, the product consistency (tolerance + / -0.05 mm) is ensured, and the production efficiency is improved. Clinical values are as follows: animal experiments prove that the postoperative infection rate is reduced to 1.2% (8.7% in a control group), and the incision healing time is shortened by 3-5 days.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and specifically to an incision protection sheath for medical engineering and its production process. Background Art

[0002] In surgical operations, incision protection is a key link to reduce postoperative infection and promote healing. In the prior art, most incision protection devices are made of silicone or polyurethane materials, and there are the following defects: 1. Insufficient material properties: Some materials have poor biocompatibility and are prone to cause tissue irritation; they may corrode or deform after long-term contact with body fluids, resulting in the failure of protection. 2. Single structure design: Traditional protection sheaths are mostly single-layer cylindrical structures, which cannot effectively isolate external pollutants, and lack buffer protection for the incision edge, easily causing secondary damage. 3. Unstable fixation: Relying on tape or suture fixation, it is easy to fall off and the operation is cumbersome, increasing the operation time. 4. Limited adaptability: It cannot be flexibly adjusted according to the incision depth or the patient's body type, resulting in insufficient fitting degree. Summary of the Invention

[0003] Aiming at the above-mentioned defects of the prior art, the purpose of the present invention is to provide an incision protection sheath for medical engineering and its production process, which adopts a multi-layer composite structure to improve anti-infection and mechanical properties; designs an adjustable fixing device to adapt to different incision depths and patient body types; and optimizes the production process to achieve low-cost and high-precision manufacturing.

[0004] To achieve the above purpose, the present invention provides the following technical solutions: An incision protection sheath for medical engineering, comprising: An outer protective film: composed of a polytetrafluoroethylene substrate and a surface-coated nano-silver composite layer, wherein the density of the nano-silver coating is 1.5 - 3.0 mg / cm², the thickness is 0.1 - 0.3 mm, and the particle size of the nano-silver particles is 20 - 50 nm; An inner buffer ring: composed of medical silicone and collagen mixed in a mass ratio of 6:4 to 8:2, with hollow microspheres uniformly dispersed inside, the diameter of the hollow microspheres is 50 - 200 μm, the wall thickness is 5 - 15 μm, and the filling rate is 10% - 30% of the buffer ring volume; An adjustable fixing system: including a magnetic anchoring piece and a shape memory alloy bracket, the bracket is woven into a mesh structure by nickel-titanium alloy wires, the diameter of the alloy wires is 0.1 - 0.3 mm, annealed at 300 - 400 °C, and has the characteristic of triggering shape recovery at 35 - 45 °C; An integrated drainage channel: provided on the side wall of the protection sheath, including at least 3 drainage holes with a pore diameter of 1 - 3 mm, the inner wall of the holes is coated with a heparinized coating, and the channel is externally connected to a standard negative pressure interface, and the interface diameter matches the clinical drainage tube.

[0005] Preferably, the magnetic anchoring sheet is composed of a flexible magnet and medical-grade polyurethane, and its surface is coated with a hydroxyapatite coating by plasma spraying. The coating thickness is 10 - 30 μm, the magnetic induction intensity of the magnet is 0.3 - 0.8 T, and the skin contact surface is covered with a biocompatible adhesive layer.

[0006] Preferably, the ratio of the expanded diameter to the compressed diameter of the shape memory alloy stent is 2:1 to 5:1, the fitting pressure with the incision edge after expansion is 0.1 - 0.5 N / cm², and the surface of the stent is treated with a titanium nitride coating, and the coating thickness is 2 - 5 μm.

[0007] Preferably, the material of the hollow microspheres is poly(lactic-co-glycolic acid), its degradation period is 30 - 90 days, the pH value of the degradation product is 6.5 - 7.5, and the microspheres are filled with chitosan gel, and the gel concentration is 5% - 15% (w / v).

[0008] Preferably, the heparinized coating of the drainage channel is composed of sodium heparin and polyvinylpyrrolidone blended at a mass ratio of 1:3 to 1:5, the coating thickness is 5 - 20 μm, and the heparin release rate is 0.1 - 0.5 μg / cm²·h.

[0009] Preferably, the porosity of the PTFE substrate of the outer protective film is 30 - 50%, the pore diameter is 0.5 - 5 μm, and the silver nanocomposite layer is combined with the PTFE substrate by chemical vapor deposition process, and the bonding strength ≥ 5 MPa.

[0010] A production process of an incision protection sleeve for medical engineering, comprising the following steps: Step S1: Preparation of the outer protective film: Immerse the PTFE film in a dispersion liquid containing silver nanoparticles, the dispersion liquid concentration is 5 - 10 mg / mL, ultrasonically treat for 20 - 40 minutes, and then dry in a vacuum drying oven at 50 - 70 °C to form a silver nanocomposite layer; Step S2: Molding of the inner buffer ring: Mix medical silicone and collagen in proportion, add PLGA hollow microspheres, degas for 30 - 60 minutes under a vacuum degree ≤ 0.1 MPa, inject into a mold, and vulcanize and mold at 80 - 100 °C, and the pressure holding time is 10 - 30 minutes; Step S3: Structural assembly: Use a Nd:YAG laser welding machine with a wavelength of 1064 nm, at a power of 15 - 25 W and a welding speed of 3 - 8 mm / s, to seamlessly weld the outer protective film and the inner buffer ring along the edge, and the weld width is 0.1 - 0.5 mm; Step S4: Fixing system integration: Anneal the nitinol wire at 350 ± 10 °C for 10 - 15 minutes in a protective atmosphere (argon), then braid it into a mesh stent and embed it into the edge of the protective sleeve through a hot pressing process; After the magnetic anchoring piece is plasma-sprayed with a hydroxyapatite coating, it is adhesively fixed to the stent with medical-grade epoxy resin, and the curing condition is to stand still for 24 hours at 25 °C and 50% humidity; Step S5: Functionalization treatment: Spray a heparin sodium-PVP mixed solution on the inner wall of the drainage channel at a spraying rate of 0.5 - 1.5 mL / min, and then cure it in an oven at 40 - 60 °C for 2 - 4 hours; Step S6: Sterilization and packaging: Sterilize with ethylene oxide, control the gas concentration at 600 - 1000 mg / L, relative humidity at 50 - 70%, temperature at 45 - 55 °C, and sterilization time at 3 - 6 hours, and then seal it in a double-layer aluminum-plastic sterile bag.

[0011] Preferably, the annealing treatment of the nitinol wire in step S4 includes: The first stage: Heat up to 350 °C at a rate of 10 - 15 °C / min and keep it warm for 10 minutes; The second stage: Cool down to 200 °C at a rate of 5 - 10 °C / min, and then naturally cool to room temperature.

[0012] Preferably, the preparation method of the heparin sodium-PVP mixed solution in step S5 is: Dissolve heparin sodium and PVP in deionized water at a mass ratio of 1:4, with a stirring speed of 200 - 400 rpm and a temperature of 25 - 40 °C until a homogeneous and transparent solution is formed.

[0013] Preferably, the inner layer of the double-layer aluminum-plastic sterile bag in step S6 is a polyethylene film, the outer layer is an aluminum foil composite film, the sealing strength is ≥ 3.0 N / 15 mm, and the air permeability is ≤ 0.1 cm³ / (m²·24 h·0.1 MPa).

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. Material innovation: The PTFE-nano silver composite layer takes into account both antibacterial and durability, and the collagen-silica gel buffer layer promotes tissue repair.

[0015] 2. Structural innovation: Magnetic fixation + shape memory stent realizes "one-key" rapid installation, reducing the intraoperative operation time by more than 20%.

[0016] 3. Process innovation: The combination of laser welding and plasma spraying technology ensures product consistency (tolerance ± 0.05 mm).

[0017] 4. Clinical value: Verified by animal experiments, the postoperative infection rate is reduced to 1.2% (the control group is 8.7%), and the incision healing time is shortened by 3 - 5 days. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a perspective view of the present invention; Figure 2 is a front view of the present invention; Figure 3 is a sectional view of the present invention; Figure 4 is a process flow chart of the production of the incision protection sheath of the present invention.

[0019] Reference numerals in the figures: 101, outer protective film; 102, inner buffer ring; 103, adjustable fixing system; 103a, magnetic anchoring piece; 103b, shape memory alloy bracket; 104, integrated drainage channel; 104a, negative pressure interface. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] Please refer to Figures 1-4 , the present invention provides a technical solution: Embodiment

[0021] A surgical incision protection sheath for medical engineering, comprising: an outer protective film 101: composed of a PTFE substrate and a surface-coated nano-silver composite layer, wherein the density of the nano-silver coating is 1.5 - 3.0 mg / cm², the thickness is 0.1 - 0.3 mm, and the particle size of the nano-silver particles is 20 - 50 nm; an inner buffer ring 102: formed by mixing medical-grade silicone and collagen in a mass ratio of 6:4 to 8:2, with hollow microspheres uniformly dispersed inside. The hollow microspheres have a diameter of 50 - 200 μm, a wall thickness of 5 - 15 μm, and a filling rate of 10% - 30% of the buffer ring volume; an adjustable fixation system 103: including a magnetic anchoring sheet 103a and a shape memory alloy stent 103b. The stent is woven into a mesh structure by nickel-titanium alloy wires with a wire diameter of 0.1 - 0.3 mm, annealed at 300 - 400 °C, and has the characteristic of triggering shape recovery at 35 - 45 °C; an integrated drainage channel 104: provided on the side wall of the protection sheath, including at least 3 drainage holes with a pore diameter of 1 - 3 mm. The inner wall of the holes is coated with a heparinized coating, and the channel is externally connected to a standard negative pressure interface 104a. The diameter of the interface matches that of a clinical drainage tube. The magnetic anchoring sheet 103a is composed of a flexible magnet and medical-grade polyurethane, with a surface plasma-sprayed hydroxyapatite coating having a thickness of 10 - 30 μm. The magnetic induction intensity of the magnet is 0.3 - 0.8 T, and the skin contact surface is covered with a biocompatible adhesive layer. The expansion diameter to compression diameter ratio of the shape memory alloy stent 103b is 2:1 to 5:1, and the fitting pressure with the incision edge after expansion is 0.1 - 0.5 N / cm². The surface of the stent is treated with a titanium nitride coating with a thickness of 2 - 5 μm. The material of the hollow microspheres is poly(lactic-co-glycolic acid) copolymer, with a degradation period of 30 - 90 days, a degradation product pH value of 6.5 - 7.5, and the microspheres are filled with chitosan gel with a gel concentration of 5% - 15% (w / v). The heparinized coating of the drainage channel 104 is composed of heparin sodium and polyvinylpyrrolidone blended in a mass ratio of 1:3 to 1:5, with a coating thickness of 5 - 20 μm and a heparin release rate of 0.1 - 0.5 μg / cm²·h. The porosity of the PTFE substrate of the outer protective film 101 is 30% - 50%, the pore diameter is 0.5 - 5 μm, and the nano-silver composite layer is combined with the PTFE substrate by chemical vapor deposition, with a bonding strength ≥ 5 MPa.

[0022] A production process for a surgical incision protection sheath for medical engineering, comprising the following steps: Step S1: Preparation of the outer protective film 101: Immerse the PTFE film in a dispersion liquid containing nano-silver particles with a dispersion liquid concentration of 5 - 10 mg / mL, perform ultrasonic treatment for 20 - 40 minutes, and then dry it in a vacuum drying oven at 50 - 70 °C to form a nano-silver composite layer; Step S2: Molding of the inner buffer ring 102: After mixing medical silicone and collagen in proportion, add PLGA hollow microspheres, degas for 30 - 60 minutes under a vacuum of ≤0.1 MPa, inject into a mold, and vulcanize and mold at 80 - 100 °C with a pressure holding time of 10 - 30 minutes; Step S3: Structural assembly: Use a Nd:YAG laser welding machine with a wavelength of 1064 nm, at a power of 15 - 25 W and a welding speed of 3 - 8 mm / s, to seamlessly weld the outer protective film 101 and the inner buffer ring 102 along the edge, with a weld width of 0.1 - 0.5 mm; Step S4: Fixing system integration: Anneal the nitinol wire at 350 ± 10 °C for 10 - 15 minutes under a protective atmosphere (argon), then braid it into a mesh stent 103b and embed it into the edge of the protective sleeve through a hot pressing process; After plasma spraying a hydroxyapatite coating on the magnetic anchoring sheet 103a, bond and fix it to the stent 103b with medical-grade epoxy resin, and the curing condition is to stand still for 24 hours at 25 °C and a humidity of 50%; Step S5: Functionalization treatment: Spray a heparin sodium - PVP mixed solution on the inner wall of the drainage channel 104 at a spraying rate of 0.5 - 1.5 mL / min, and then cure it in an oven at 40 - 60 °C for 2 - 4 hours; Step S6: Sterilization and packaging: Sterilize with ethylene oxide, control the gas concentration at 600 - 1000 mg / L, relative humidity at 50 - 70%, temperature at 45 - 55 °C, and sterilization time at 3 - 6 hours, and then seal it in a double-layer aluminum-plastic sterile bag.

[0023] The annealing treatment of the nitinol wire in Step S4 includes: The first stage: Heat up to 350 °C at a rate of 10 - 15 °C / min and hold for 10 minutes; The second stage: Cool down to 200 °C at a rate of 5 - 10 °C / min, and then naturally cool to room temperature.

[0024] The preparation method of the heparin sodium - PVP mixed solution in Step S5 is: Dissolve heparin sodium and PVP in deionized water at a mass ratio of 1:4, with a stirring speed of 200 - 400 rpm and a temperature of 25 - 40 °C until a homogeneous and transparent solution is formed.

[0025] The inner layer of the double-layer aluminum-plastic sterile bag in Step S6 is a polyethylene film, and the outer layer is an aluminum foil composite film, with a sealing strength ≥3.0 N / 15 mm and an air permeability ≤0.1 cm³ / (m²·24 h·0.1 MPa).

[0026] Example 2: Application in laparoscopic surgery Select the protective sleeve model according to the incision length (5 cm), and pre-compress the stent to a diameter of 2 cm; After being placed into the incision, the shape memory alloy is activated with normal saline at 40°C, and the stent automatically expands to 5 cm and fits against the abdominal wall; The magnetic anchoring sheet is adsorbed on the skin surface, and the fixing force is ≥ 0.5 N / cm²; Connect the negative pressure drainage device. Remove the protective cover 24 hours after the operation, and there is no tissue adhesion phenomenon.

[0027] Example 3: Optimization of production process parameters Concentration of nano-silver coating: 2.5 mg / cm² (antibacterial rate 99.3%); Laser welding power: 20 W, speed 5 mm / s, and the weld strength reaches 15 MPa; Sterilization conditions: ethylene oxide concentration 800 mg / L, humidity 60%, temperature 50°C, action time 4 h.

Claims

1. A cut protection sleeve for medical engineering, characterized in that, Comprising: Outer protective film (101): Composed of a PTFE substrate and a surface-coated nano-silver composite layer, where the density of the nano-silver coating is 1.5 - 3.0 mg / cm², the thickness is 0.1 - 0.3 mm, and the particle size of the nano-silver particles is 20 - 50 nm; Inner buffer ring (102): Made by mixing medical-grade silicone and collagen in a mass ratio of 6:4 to 8:2, with hollow microspheres uniformly dispersed inside. The diameter of the hollow microspheres is 50 - 200 μm, the wall thickness is 5 - 15 μm, and the filling rate is 10% - 30% of the volume of the buffer ring; Adjustable fixation system (103): Includes a magnetic anchoring sheet (103a) and a shape memory alloy stent (103b). The stent is woven into a mesh structure by nickel-titanium alloy wires with a wire diameter of 0.1 - 0.3 mm, annealed at 300 - 400 °C, and has the characteristic of triggering shape recovery at 35 - 45 °C; Integrated drainage channel (104): Provided on the side wall of the protective sleeve, including at least 3 drainage holes with a pore diameter of 1 - 3 mm. The inner wall of the holes is coated with a heparinized coating. The channel is externally connected to a standard negative pressure interface (104a), and the interface diameter matches that of a clinical drainage tube.

2. The incision protection sheath for medical engineering according to claim 1, wherein: The magnetic anchoring sheet (103a) is composed of a flexible magnet and medical-grade polyurethane, with a surface plasma-sprayed hydroxyapatite coating having a thickness of 10 - 30 μm. The magnetic induction intensity of the magnet is 0.3 - 0.8 T, and the skin contact surface is covered with a biocompatible adhesive layer.

3. The incision protection sheath for medical engineering according to claim 1, characterized in that: The expansion diameter to compression diameter ratio of the shape memory alloy stent (103b) is 2:1 to 5:

1. The fitting pressure with the incision edge after expansion is 0.1 - 0.5 N / cm², and the surface of the stent is treated with a titanium nitride coating with a coating thickness of 2 - 5 μm.

4. The incision protection sheath for medical engineering according to claim 1, wherein: The material of the hollow microspheres is poly(lactic-co-glycolic acid), with a degradation period of 30 - 90 days, a degradation product pH value of 6.5 - 7.5, and the microspheres are filled with chitosan gel with a gel concentration of 5% - 15% (w / v).

5. The incision protection sheath for medical engineering according to claim 1, wherein: The heparinized coating of the drainage channel (104) is formed by blending sodium heparin and polyvinylpyrrolidone in a mass ratio of 1:3 to 1:5, with a coating thickness of 5 - 20 μm and a heparin release rate of 0.1 - 0.5 μg / cm²·h.

6. The incision protection sheath for medical engineering according to claim 1, characterized in that: The porosity of the PTFE substrate of the outer protective film (101) is 30 - 50%, the pore diameter is 0.5 - 5 μm, and the nano-silver composite layer is combined with the PTFE substrate through a chemical vapor deposition process, with a bonding strength ≥5 MPa.

7. The production process of an incision protection sleeve for medical engineering according to any one of claims 1-6, characterized in that, Including the following steps: Step 1: Preparation of the outer protective film (101): Immerse the PTFE film in a dispersion liquid containing nano-silver particles with a dispersion liquid concentration of 5 - 10 mg / mL, ultrasonically treat for 20 - 40 minutes, and then dry in a vacuum drying oven at 50 - 70 °C to form a nano-silver composite layer; Step 2: Molding of the inner buffer ring (102): After mixing medical silicone and collagen in proportion, PLGA hollow microspheres are added, degassed for 30 - 60 minutes under a vacuum degree ≤ 0.1 MPa, injected into a mold, and vulcanized and molded at 80 - 100 °C with a pressure holding time of 10 - 30 minutes; Step 3: Structural assembly: Using a Nd:YAG laser welding machine with a wavelength of 1064 nm, at a power of 15 - 25 W and a welding speed of 3 - 8 mm / s, the outer protective film (101) and the inner buffer ring (102) are seamlessly welded along the edge, and the weld width is 0.1 - 0.5 mm; Step S4: Fixing system integration: The nitinol wire is annealed at 350 ± 10 °C for 10 - 15 minutes in a protective atmosphere (argon), then woven into a mesh stent (103b), and embedded in the edge of the protective sleeve through a hot pressing process; After the magnetic anchoring sheet (103a) is plasma sprayed with a hydroxyapatite coating, it is adhesively fixed to the stent (103b) with a medical-grade epoxy resin, and the curing condition is to stand still for 24 hours at 25 °C and a humidity of 50%; Step S5: Functionalization treatment: A heparin sodium - PVP mixed solution is sprayed on the inner wall of the drainage channel (104) at a spraying rate of 0.5 - 1.5 mL / min, and then cured in an oven at 40 - 60 °C for 2 - 4 hours; Step S6: Sterilization and packaging: Ethylene oxide sterilization is adopted, controlling the gas concentration to be 600 - 1000 mg / L, relative humidity 50 - 70%, temperature 45 - 55 °C, and sterilization time 3 - 6 hours, and then sealed in a double-layer aluminum-plastic sterile bag.

8. The production process of an incision protection sleeve for medical engineering according to claim 7, characterized in that: The annealing treatment of the nitinol wire in the step S4 includes: The first stage: Heating to 350 °C at a rate of 10 - 15 °C / min and holding for 10 minutes; The second stage: Cooling to 200 °C at a rate of 5 - 10 °C / min, and then naturally cooling to room temperature.

9. The production process of an incision protection sheath for medical engineering according to claim 7, characterized in that: The preparation method of the heparin sodium - PVP mixed solution in the step S5 is: Dissolving heparin sodium and PVP in deionized water at a mass ratio of 1:4, with a stirring speed of 200 - 400 rpm and a temperature of 25 - 40 °C until a homogeneous and transparent solution is formed.

10. The production process of an incision protection sheath for medical engineering according to claim 7, characterized in that: The inner layer of the double-layer aluminum-plastic sterile bag in the step S6 is a polyethylene film, and the outer layer is an aluminum foil composite film, with a sealing strength ≥ 3.0 N / 15 mm and an air permeability ≤ 0.1 cm³ / (m²·24 h·0.1 MPa).

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