Pancreatic fistula prevention stent

Abstract

The utility model discloses a can reduce pancreatic fistula risk, the initiative promotion tissue healing, the pancreatic fistula prevention support of bracket degradable. The pancreatic fistula prevention support includes inner layer support pipe, both ends of inner layer support pipe all are provided with blunt head, and the blunt head on one end is provided with opening, and the blunt head is provided with expansion layer, and the inner layer support pipe is divided into two sections by the middle position, and the section of being close to opening is provided with drainage hole, and the other section is provided with one -way liquid structure, and the inner layer support pipe inner wall is provided with anti pancreatic enzyme coating, and the inner layer support pipe outer cylindrical surface is provided with medicine slow -release layer, and the inner layer support pipe adopts the biodegradable biological material and makes. Adopt the pancreatic fistula prevention support and reduce the corrosion risk through the physical isolation pancreatic juice and the anastomotic mouth, and the medicine slow -release direct action is in local, and shortens the healing time, and the biodegradable biological material does not need to take out, and reduces the medical cost, and the structure miniaturization can be compatible with laparoscope / robot operation.

Description

Technical Field

[0001] This utility model relates to a protective stent for pancreaticojejunostomy, and more particularly to a stent for preventing pancreatic fistula. Background Technology

[0002] Postoperative pancreatic fistula (POPF) is one of the most serious complications after pancreatic surgery (such as pancreaticoduodenectomy), with an incidence of 5%-30%, which can lead to infection, bleeding, and even death. Currently, both endoscopic pancreatic surgery and traditional open surgery use stents placed at the pancreaticojejunostomy to reduce the occurrence of pancreatic fistula.

[0003] Current techniques typically involve implanting a traditional stent at the pancreaticojejunostomy site or suturing the anastomosis for reinforcement. Traditional stents are often non-biodegradable plastic tubes, requiring a second surgery for removal or remaining in the body long-term. They are prone to stent displacement or blockage, and cannot actively promote tissue healing. Furthermore, they lack the function of regulating pancreatic juice secretion, making the anastomosis susceptible to fistula or stenosis due to pancreatic juice corrosion. Summary of the Invention

[0004] The technical problem to be solved by this utility model is to provide a pancreatic fistula prevention stent that can reduce the risk of pancreatic fistula, actively promote tissue healing, and is biodegradable.

[0005] The technical solution adopted by this utility model to solve its technical problem is: a pancreatic fistula prevention stent, including an inner support tube; both ends of the inner support tube are provided with blunt heads; an opening is provided on one of the blunt heads; and an expansion layer is provided on the blunt head. The inner support tube is divided into two sections in the middle. One section near the opening is provided with a drainage hole, and the other section is provided with a one-way liquid inlet structure. The inner wall of the inner support tube is coated with an anti-trypsin layer; the outer cylindrical surface of the inner support tube is coated with a drug sustained-release layer; the inner support tube is made of biodegradable biomaterials.

[0006] Furthermore, the drug sustained-release layer is loaded with dexamethasone.

[0007] Specifically, the inner support tube is made of polylactic acid or polycaprolactone.

[0008] Specifically, the antitrypsin coating is a polyethylene glycol coating.

[0009] Specifically, the drug sustained-release layer is an epidermal growth factor coating or a fibrin glue coating.

[0010] Furthermore, an opening is provided on the blunt end of one end of the inner support tube, and a one-way liquid inlet structure is provided on the blunt end of the other end.

[0011] Specifically, the one-way liquid inlet structure includes a through hole, and a one-way valve is provided inside the through hole; or the one-way liquid inlet structure includes a through hole, and two elastic valves that close towards the center of the through hole are provided inside the through hole.

[0012] Specifically, the expanded layer is a PNIPAm hydrogel and a PCL nanofiber mesh reinforcement layer.

[0013] The beneficial effects of this utility model are: The inner support tube of the pancreatic fistula prevention stent described in this invention is made of biodegradable biomaterial, thus enabling biodegradation and avoiding secondary trauma. Secondly, the outer surface of the inner support tube is provided with a drug sustained-release layer, which can actively promote tissue healing and reduce inflammatory response; Furthermore, the inner surface of the inner support tube is coated with an anti-pancreatic enzyme coating to prevent pancreatic juice from corroding the inner support tube. Secondly, the inner support tube has an opening at one end, a drainage hole at one end, and a one-way fluid inlet structure at the other end to ensure smooth drainage of pancreatic juice. Secondly, the inner support tube has rounded blunt tips at both ends to facilitate surgical implantation; Furthermore, an expansion layer is provided on the blunt ends of both ends of the inner support tube. The expansion layer expands at body temperature, allowing the support frame to fit snugly against the inner wall and preventing the support from shifting.

[0014] In summary, the pancreatic fistula prevention stent of this invention reduces the risk of corrosion by physically isolating pancreatic juice from the anastomosis; the sustained-release drug acts directly on the local area, shortening the healing time; the biodegradable material does not need to be removed, reducing medical costs; and the miniaturized structure is compatible with laparoscopic / robotic operations. Attached Figure Description

[0015] Figure 1 This is a perspective view of the pancreatic fistula prevention stent in an embodiment of this utility model; Figure 2 This is a front view of the pancreatic fistula prevention stent in an embodiment of this utility model; Figure 3 This is a schematic diagram of the structure of the pancreatic fistula prevention stent in an embodiment of this utility model; Figure 4 yes Figure 3 A magnified view of part A in the image; Figure 5 This is a schematic diagram of the unidirectional liquid inlet structure using a unidirectional movable valve in this embodiment of the present invention; Figure 6 This is a schematic diagram of the unidirectional liquid inlet structure with two elastic flaps in an embodiment of this utility model; The diagram shows: 100 - inner support tube, 110 - drainage hole, 120 - one-way liquid inlet structure, 130 - blunt tip, 140 - opening, 200 - anti-trypsin coating, 300 - drug sustained-release layer, 400 - expansion layer. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] like Figures 1 to 6 As shown, the pancreatic fistula prevention stent of this utility model includes an inner support tube 100; both ends of the inner support tube 100 are provided with blunt heads 130; one end of the blunt head 130 is provided with an opening 140; and an expansion layer 400 is provided on the blunt head 130.

[0018] The main function of the inner support tube 100 is to provide support and facilitate the drainage of pancreatic juice. The inner support tube 100 is made of biodegradable biomaterials, allowing it to degrade and avoiding the need for secondary surgery. Specifically, the inner support tube 100 is made of polylactic acid (PLA) or polycaprolactone (PCL), with a degradation time of 4-8 weeks. The selection of these two materials provides suitable mechanical strength for supporting the anastomosis.

[0019] The main function of providing blunt tips 130 at both ends of the inner support tube 100 is to facilitate stent implantation during surgery. Specifically, the blunt tips 130 are curved. An expansion layer 400 is provided on the blunt tips 130, which expands at a temperature of 35-37 degrees Celsius. Therefore, when the pancreatic fistula prevention stent is placed in the body, the expansion layer 400 expands, causing the blunt tips 130 to adhere to the inner wall of the intestinal tract, effectively preventing displacement of the pancreatic fistula prevention stent. Specifically, the expansion layer 400 is a PNIPAm hydrogel + PCL nanofiber mesh reinforcement layer. The PNIPAm hydrogel is poly(N-isopropylacrylamide), which expands rapidly at body temperature, reaching 200% expansion within 2 minutes. The PCL nanofiber mesh is an expandable polycaprolactone fiber mesh; the PCL mesh limits excessive expansion, providing radial support of 15-20 kPa, meeting the safe pressure threshold for pancreaticojejunostomy.

[0020] The inner support tube 100 is divided into two sections from the middle position. One section near the opening 140 is provided with a drainage hole 110, and the other section is provided with a one-way liquid inlet structure 120. An opening is provided at the blunt end 130 of the inner support tube 100, and a drainage hole 110 is provided on one section of the inner support tube 100, while a one-way fluid inlet structure 120 is provided on the other section. This facilitates the drainage of pancreatic juice and ensures smooth drainage. The one-way fluid inlet structure 120 prevents pancreatic juice reflux. The opening at the blunt end 130 and the drainage hole 110 on one section facilitate the drainage of pancreatic juice. During the operation, one end of the inner support tube 100 with the opening 130 is inserted into the intestinal tract, and the other end is inserted into the pancreatic duct, thereby allowing pancreatic juice to flow into the intestine and preventing intestinal fluid from refluxing into the pancreatic duct.

[0021] To facilitate better drainage of pancreatic juice, the inner support tube 100 has an opening 140 on one blunt end 130 and a one-way fluid inlet structure 120 on the other blunt end 130.

[0022] The main function of the one-way fluid inlet structure 120 is to ensure that fluid outside the inner support tube 100 can only enter the inner support tube 100, while fluid inside the inner support tube 100 cannot flow out. Therefore, by implanting the end of the inner support tube 100 with the one-way fluid inlet structure 120 into the pancreatic duct, pancreatic juice can enter the inner support tube 100, preventing fluid inside the inner support tube 100 from entering the pancreatic duct.

[0023] The unidirectional liquid inlet structure 120 can be implemented in various ways, such as... Figure 5 As shown, one type of the unidirectional liquid inlet structure 120 includes a through hole 121, and a unidirectional valve 122 is provided inside the through hole. Figure 6 As shown, another type is a unidirectional liquid inlet structure 120, which includes a through hole 121, and two elastic flaps 123 that close towards the center of the through hole are provided inside the through hole 121.

[0024] An anti-trypsin coating 200 is provided on the inner wall of the inner support tube 100; a drug sustained-release layer 300 is provided on the outer cylindrical surface of the inner support tube 100; the inner support tube 100 is made of biodegradable biomaterials.

[0025] An anti-trypsin coating 200 is provided on the inner wall of the inner support tube 100 to effectively prevent the stent from being corroded by pancreatic juice. Specifically, the anti-trypsin coating 200 is a polyethylene glycol coating.

[0026] The main function of setting the drug-releasing layer 300 on the outer cylindrical surface of the inner support tube 100 is to accelerate anastomotic repair. Specifically, the drug-releasing layer 300 is an epidermal growth factor (EGF) coating or a fibrin glue coating. Adding epidermal growth factor (EGF) or fibrin glue to the drug-releasing layer 300 can promote healing and accelerate mucosal repair.

[0027] To further reduce the risk of inflammation, the drug-releasing layer 300 is loaded with anti-inflammatory drugs such as dexamethasone, which are released for 2-4 weeks to inhibit anastomotic inflammation.

Claims

1. A pancreatic fistula prevention stent, characterized in that: It includes an inner support tube (100); both ends of the inner support tube (100) are provided with blunt ends (130); one end of the blunt end (130) is provided with an opening (140); an expansion layer (400) is provided on the blunt end (130). The inner support tube (100) is divided into two sections from the middle position. One section near the opening (140) is provided with a drainage hole (110), and the other section is provided with a one-way liquid inlet structure (120). The inner wall of the inner support tube (100) is provided with an anti-trypsin coating (200); a drug sustained-release layer (300) is provided on the outer cylindrical surface of the inner support tube (100); the inner support tube (100) is made of biodegradable biomaterial.

2. The pancreatic fistula prevention stent as described in claim 1, characterized in that: The drug sustained-release layer (300) is loaded with dexamethasone.

3. The pancreatic fistula prevention stent as described in claim 1, characterized in that: The inner support tube (100) is made of polylactic acid or polycaprolactone.

4. The pancreatic fistula prevention stent as described in claim 1, characterized in that: The antitrypsin coating (200) is a polyethylene glycol coating.

5. The pancreatic fistula prevention stent as described in claim 1, characterized in that: The drug sustained-release layer (300) is an epidermal growth factor coating or a fibrin glue coating.

6. The pancreatic fistula prevention stent as described in claim 1, characterized in that: An opening (140) is provided on the blunt end (130) of one end of the inner support tube (100), and a one-way liquid inlet structure (120) is provided on the blunt end (130) of the other end.

7. The pancreatic fistula prevention stent as described in claim 1, characterized in that: The one-way liquid inlet structure (120) includes a through hole (121), and a one-way valve (122) is provided inside the through hole; or the one-way liquid inlet structure (120) includes a through hole (121), and an elastic valve (123) with two petals closing towards the center of the through hole is provided inside the through hole (121).

8. The pancreatic fistula prevention stent as described in claim 3, characterized in that: The expanded layer (400) is a PNIPAm hydrogel and a PCL nanofiber mesh reinforcement layer.

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