Artery perfusion tube for small animal in-vitro lung perfusion

Abstract

The invention relates to the technical field of medicine, and provides an arterial perfusion tube for small animal in-vitro lung perfusion, which comprises a perfusion main tube group, the perfusion main tube group is U-shaped, the output end of the perfusion main tube group is fixedly connected with a conical insertion conical head, the top end of the conical insertion conical head is in the shape of a sharp-free smooth cone, and the top end of the conical insertion conical head is connected with the perfusion main tube group. The perfusion main pipe group is inserted into a pulmonary artery trunk of a mouse or a rat, and a rotating part for steering is arranged at the bottom of the middle end of the perfusion main pipe group; the output end of the first perfusion catheter is communicated with the input end of the main perfusion pipe set, and the input end of the first perfusion catheter is connected with a second perfusion catheter through an air filtering assembly so as to be connected into an external perfusion liquid supply part. The integral U-shaped smooth pipeline structure is adopted, and the device can naturally conform to the thoracic anatomy direction of an experimental animal in the implanting and connecting process, so that the infusion tube implanting process is remarkably simplified, the operation preparation time is shortened, and the dependence on the thoracic anatomy operation skill of an operator is reduced.

Description

Technical Field

[0001] This invention relates to the field of medical technology, specifically to an arterial perfusion tube for extracorporeal lung perfusion in small animals. Background Technology

[0002] Improving donor lung quality is crucial for increasing lung transplant success rates. Ex vivo lung perfusion (EVLP) has been proven to be an effective technique for improving donor lung quality, but many issues remain to be studied and clarified. Small animal EVLP systems are a common method for studying ex vivo lung perfusion, characterized by high feasibility, reproducibility, and low cost. However, constructing relevant animal models is difficult and technically demanding. Currently, the arterial perfusion tubing used in EVLP systems is mostly made from syringe needles or modified commercial stainless steel tubing, with unreliable fixation methods that are prone to twisting or detachment. Furthermore, the lack of optimized design for small animal physiology makes it easy for excessive pressure in the pulmonary artery to occur, leading to leakage or even pulmonary edema unrelated to the experimental content, affecting the scientific validity and reproducibility of the experimental results. Additionally, the fixed angle of the perfusion tubing makes it difficult to adjust the angle during ex vivo perfusion.

[0003] In existing technologies, small animal EVLP arterial perfusion catheters primarily rely on manual suturing, using 2-0 or 3-0 sutures for fixation. Some studies have attempted to use metal or polymer cannulas for assistance, but these are typically simple tubular structures, with fixation relying on roughening of the outer wall or a few protrusions, lacking a reliable anti-slip mechanism. After in vivo perfusion catheter insertion and fixation, ex vivo perfusion is required, often necessitating angle adjustment. Current perfusion catheters have non-adjustable angles, making them prone to torsion and tearing upon connection. Some commercially available cannulas may lack biofunctional coatings.

[0004] Existing perfusion tubing lacks a fixing device, making it prone to slippage and twisting, leading to perfusion failure. Furthermore, the angle of existing perfusion tubing is not adjustable, requiring repeated angle adjustments during ex vivo perfusion, prolonging ischemic time before mechanical perfusion, and increasing the risk of detachment of the perfusion tubing and associated blood vessels or reduced perfusion efficacy. Therefore, there is a need for an arterial perfusion tubing for ex vivo lung perfusion in small animals. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an arterial perfusion tube for in vitro lung perfusion in small animals. This solves the problems of existing perfusion tubes lacking a fixing device, making them prone to slippage and twisting, leading to perfusion failure. Furthermore, the angle of existing perfusion tubes is not adjustable, requiring repeated angle adjustments during ex vivo perfusion, which prolongs the ischemic time before in vitro perfusion and easily causes detachment of the perfusion tube and blood vessels or a decrease in perfusion effect.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An arterial perfusion catheter for extracorporeal lung perfusion in small animals, comprising: The perfusion main tube assembly is U-shaped, and a conical insertion cone is fixedly connected to the output end of the perfusion main tube assembly. The top of the conical insertion cone is a smooth cone without sharp edges, for insertion into the main pulmonary artery of mice or rats. A rotating part for steering is provided at the bottom of the middle end of the perfusion main tube assembly. Infusion conduit one, the output end of which is connected to the input end of the infusion main tube assembly, and the input end of the infusion conduit one is connected to infusion conduit two through an air filter assembly to access an external infusion liquid supply unit; A chassis, with a sleeve one fixedly connected to one end and a sleeve two provided at the other end of the chassis. The sleeve one and the sleeve two are connected on adjacent sides by a connecting shaft to change the relative angle between the two sleeves one. Multiple fixed snap-fit ​​sleeves are fixedly connected to the inner wall of the sleeve one. A sliding snap-fit ​​sleeve is connected to the inside of the sleeve two by a traction assembly. Both the fixed snap-fit ​​sleeves and the sliding snap-fit ​​sleeves are fitted onto the outer wall of the infusion conduit two.

[0007] Preferably, both the input and output ends of the infusion main tube assembly are provided with concave and convex portions. One of the concave and convex portions is located on the bottom side of the conical insertion cone, and the inner wall of the other concave and convex portion is engaged with a retaining tube. The outer wall of the retaining tube is in contact with the inner wall of the concave and convex portion, and the input end of the retaining tube is fixedly connected to the output end of the infusion conduit.

[0008] Preferably, the air filtration assembly includes a transparent cylinder, one end of which is rotatably connected to and communicates with an infusion conduit, and the other end of which is rotatably connected to and communicates with an infusion conduit. The inner wall of the transparent cylinder is fitted with a hydrophobic microporous filter membrane for actively blocking and removing tiny air bubbles in the infusion fluid.

[0009] Preferably, the pore size of the hydrophobic microporous filter membrane is 0.22 to 0.45 μm.

[0010] Preferably, the connecting shaft includes two connecting shafts, one of which is fixedly connected to sleeve one and the other is fixedly connected to sleeve two. The two connecting shafts are connected by rotation on their adjacent sides. An inner shaft slides vertically inside the top connecting shaft. A spline shaft is fixedly connected to the bottom side of the inner shaft. A spline groove is opened in the center of the bottom connecting shaft, and the spline shaft is inserted into the spline groove.

[0011] Preferably, the inner wall tooth density of the spline groove is greater than the outer tooth density of the spline shaft, so that the spline shaft can be inserted into the spline groove at multiple angles. The spline shaft is made of magnet, the connecting shaft is made of iron, and the spline shaft and the spline groove are magnetically attracted to each other.

[0012] Preferably, the traction assembly includes a groove formed in the inner wall of the second sleeve, the two ends of the bottom side of the sliding snap sleeve are slidably connected to the second sleeve through the groove, and a guide post is fixedly connected to the middle of the bottom side of the sliding snap sleeve. The guide post penetrates the bottom side of the second sleeve, and a guide groove is formed on the bottom side of the chassis. The bottom end of the guide post is located inside the guide groove.

[0013] An extracorporeal lung perfusion surgical method for pulmonary artery perfusion in small animals includes the following steps: Step 1: Unseal infusion tubing 1 and infusion tubing 2. Pass infusion tubing 2 through sleeve 1 and sleeve 2, and secure the locking sleeve and sliding locking sleeve onto infusion tubing 2. Connect and secure infusion tubing 1 to the concave and convex parts via the locking tube. Step 2: Insert the cone-shaped insert of the perfusion main tube into the pulmonary artery trunk of the mouse or rat. The concave and convex parts protrude along the blood vessel wall. Use ligature to wrap and knot the concave part along the concave and convex parts to fix the pulmonary artery trunk. Step 3: Lift the inner shaft to release the rotation lock, and rotate sleeve two to adjust the orientation of irrigation catheter two so that it points towards the surgical operator. The guide post and guide groove work together to prevent excessive bending or twisting of the catheter. Step 4: Reset the inner shaft so that the splined shaft is reinserted into the spline groove, and fix the rotation angle of the two connecting shafts; Step 5: The infusion fluid enters through infusion conduit two, passing sequentially through the transparent cylinder, infusion conduit one, and the main infusion pipe assembly. Inside the transparent cylinder, a hydrophobic microporous membrane removes tiny air bubbles and air from the infusion fluid. Step 6: The perfusion fluid, after removing air bubbles, is injected into the main pulmonary artery through the perfusion main tube assembly to complete the perfusion process; Step 7: Restore the surgical area, dispose of experimental waste, and perform post-experiment disinfection and cleaning.

[0014] Working Principle: In extracorporeal lung perfusion surgery for small animal pulmonary artery perfusion, the tubing is first assembled. The disposable tubing structure of perfusion catheter one and perfusion catheter two, connected to a hydrophobic microporous filter membrane, is disassembled. One end of perfusion catheter two is passed through the interior of sleeve one and sleeve two, and the internal fixing and sliding locking sleeves are pushed open. Under external force, the fixing and sliding locking sleeves are fitted and fixed onto perfusion catheter two. One end of perfusion catheter one is inserted into the input end of the concave-convex part through its locking tube, so that the protruding structure of the locking tube fits and locks against the inner wall of the concave-convex part of the input end, thus fixing it in place. Then, the perfusion is... The conical insertion tip installed on the output end of the main unit is inserted into the pulmonary artery trunk of a mouse or rat. The ligation suture is then wrapped around the concave structure of the outer wall of the concave-convex part and knotted to fix the pulmonary artery trunk at this position. Before perfusion, referring to the surgeon's position, the inner shaft is lifted, causing the spline shaft at the bottom of the inner shaft to disengage from the spline groove. This releases the rotational lock of the connecting shaft connected to the inner shaft on another connecting shaft, allowing the connecting shaft connected to sleeve two to rotate. Simultaneously, this causes sleeve two, along with the structure including the sliding retaining sleeve, to rotate, changing the bending of the portion of the perfusion catheter two held and fixed by the sliding retaining sleeve, causing the tube body of the perfusion catheter two to face... The surgeon's position is determined by the rotation of the second sleeve. During this rotation, the guide post on the bottom side of the sliding locking sleeve is displaced due to the rotation of the second sleeve. Simultaneously, the guide post moves within the guide groove on the bottom side of the chassis and is pulled by the groove, causing it to move along with the sliding locking sleeve within the second sleeve. This pulls on the portion of the irrigation catheter that it holds and fixes, increasing the length of the curved section of the irrigation catheter. This prevents excessive bending, twisting, or folding of the curved section, allowing it to bend naturally. If this angle is opposite to the surgeon's position, the irrigation catheter is rotated 180° on the transparent cylinder again. Change the bending direction of the second perfusion catheter until it faces the operator. Then, reset the inner shaft and re-insert the splined shaft into the spline groove to fix the rotation angle of the two connecting shafts. Perform the perfusion operation. The perfusion fluid enters through the second perfusion catheter and passes through the transparent cylinder, the first perfusion catheter, and the main perfusion tube assembly in sequence. When the fluid passes through the transparent cylinder, it is blocked by the hydrophobic microporous filter membrane inside. After passing through the hydrophobic microporous filter membrane, the tiny air bubbles and air in the perfusion fluid are blocked. The perfusion fluid with the air removed is injected into the main pulmonary artery through the main perfusion tube assembly. After completing the surgical experiment, restore the surgical area, dispose of experimental waste, and complete the post-experiment disinfection and cleaning work.

[0015] This invention provides an arterial perfusion catheter for extracorporeal lung perfusion in small animals. It has the following beneficial effects: 1. This invention adopts an integral U-shaped smooth tubing structure, which can naturally conform to the anatomical direction of the experimental animal's thoracic cavity during implantation and connection, thereby significantly simplifying the perfusion tube placement process, shortening surgical preparation time, reducing reliance on the operator's thoracic anatomical manipulation skills, and the rounded transition end design of the conical insertion tip minimizes secondary damage to the vascular intima and surrounding tissues during the insertion of the perfusion tube into the pulmonary artery, reducing the risk of intraoperative bleeding, vascular tearing, etc., and providing safer conditions for subsequent stable perfusion.

[0016] 2. The present invention uses a "double protrusion-groove" precise positioning structure on the concave and convex parts of the perfusion main tube assembly to ensure that the ligation suture can be stably embedded in the designated groove area, effectively avoiding loosening, leakage or detachment of the perfusion port due to suture slippage. This structure greatly improves the reliability and success rate of anastomosis fixation while maintaining the integrity of the blood vessel.

[0017] 3. The present invention can flexibly adjust the angle to avoid traction, twisting or folding of blood vessels, thereby improving the stability of perfusion flow and pressure. This structure significantly improves the ease of operation and the matching degree of perfusion posture, and improves the accuracy and reliability of the overall perfusion system.

[0018] 4. This invention can actively block and eliminate tiny air bubbles in the perfusion fluid during the perfusion process, effectively preventing local perfusion obstruction, vascular blockage or tissue damage caused by air embolism. This function significantly improves the safety of perfusion operation and improves experimental repeatability and lung tissue perfusion quality. Attached Figure Description

[0019] Figure 1 This is a perspective view of the present invention; Figure 2 This is a schematic diagram of the infusion main tube assembly of the present invention; Figure 3 This is a schematic diagram of the connection structure of the second infusion catheter of the present invention; Figure 4 This is a schematic diagram of the structure of the sliding snap sleeve of the present invention; Figure 5 This is a schematic diagram of the rotating structure of sleeve two of the present invention; Figure 6 This is a schematic diagram showing the position of the guide post of the present invention; Figure 7 This is a schematic diagram showing the position of the spline shaft of the present invention; Figure 8 This is a schematic diagram of the rotating part of the present invention.

[0020] The components include: 1. Infusion main pipe assembly; 2. Infusion conduit one; 3. Infusion conduit two; 4. Conical insertion cone; 5. Snap-fit ​​pipe; 6. Concave and convex parts; 7. Transparent cylinder; 8. Hydrophobic microporous filter membrane; 9. Base plate; 10. Sleeve one; 11. Sleeve two; 12. Fixed snap-fit ​​sleeve; 13. Sliding snap-fit ​​sleeve; 14. Guide post; 15. Connecting shaft; 16. Inner shaft; 17. Splined shaft; 18. Rotating part. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Example: As one aspect of this application, embodiments of the present invention provide an arterial perfusion catheter for extracorporeal lung perfusion in small animals, comprising: Please see the appendix Figure 1 -Appendix Figure 2 The perfusion main assembly 1 is U-shaped. A conical insertion tip 4 is fixedly connected to the output end of the perfusion main assembly 1. The tip of the conical insertion tip 4 is a smooth, rounded cone without sharp edges, for insertion into the main pulmonary artery of mice or rats. It is hollow inside and communicates with the perfusion main assembly 1. A through-hole for fluid discharge is opened at the end. A rotating part 18 for steering is provided at the bottom of the middle section of the perfusion main assembly 1. The perfusion main assembly 1 is constructed by two pipes in conjunction with the rotating part 18, enabling fluid flow and allowing the perfusion main assembly 1 to rotate at multiple angles. The rotating part 1... 8. With a sealed design, its rotating connection structure is tightly engaged, reducing gaps. At the same time, the rotating connection part has a certain friction when rotating, so that it can only be rotated when an external force is applied, so as to ensure that it will not change direction arbitrarily during the infusion process. The infusion main pipe assembly 1 is provided with concave and convex parts 6 at both the input and output ends. One concave and convex part 6 is located on the bottom side of the conical insertion cone 4. The inner wall of the other concave and convex part 6 is engaged with the clamping pipe 5. The outer wall of the clamping pipe 5 is in contact with the inner wall of the concave and convex part 6. The input end of the clamping pipe 5 is fixedly connected to the output end of the infusion conduit 2. Specifically, the cone-shaped insertion tip 4, with its smooth, rounded cone shape at the top, avoids sharp structures piercing body tissue during insertion into the main pulmonary artery of mice or rats, preventing tissue rupture due to expansion during insertion. This rounded tip design minimizes secondary damage to the vascular intima and surrounding tissues during pulmonary artery insertion, reducing the risk of intraoperative bleeding and vascular tearing, and providing safer conditions for subsequent stable perfusion. The cone-shaped insertion tip 4, installed on the output end of the perfusion main tube assembly 1, is inserted into the main pulmonary artery of mice or rats. The ligation suture is then wrapped around the concave structure of the outer wall of the concave-convex part 6 and knotted to fix the main pulmonary artery at this position. Wrapping the suture around the concave structure of the outer wall of the concave-convex part 6 effectively prevents loosening, leakage, or detachment of the perfusion port due to suture slippage. This structure significantly improves the reliability and success rate of anastomosis fixation while maintaining vascular integrity.

[0023] Please see the appendix Figure 1 -Appendix Figure 2 The infusion conduit 2 has its output end connected to the input end of the infusion main assembly 1. The input end of the infusion conduit 2 is connected to the infusion conduit 3 via an air filter assembly to access the external infusion liquid supply unit. The air filter assembly includes a transparent cylinder 7. One end of the transparent cylinder 7 is rotatably connected to and connected to the infusion conduit 2. The other end of the transparent cylinder 7 is rotatably connected to and connected to the infusion conduit 3. The inner wall of the transparent cylinder 7 is equipped with a hydrophobic microporous filter membrane 8 for actively blocking and removing tiny air bubbles in the infusion liquid. The pore size of the hydrophobic microporous filter membrane 8 is 0.22 to 0.45 μm. Specifically, both perfusion catheter 1 (2) and perfusion catheter 2 (3) are flexible tubes. Before performing extracorporeal lung perfusion surgery for small animal pulmonary artery perfusion, the tubes need to be assembled first. The disposable tube structures of perfusion catheter 1 (2) and perfusion catheter 2 (3), which are connected to the hydrophobic microporous filter membrane 8, are unsealed. This structure, along with the perfusion main tube assembly 1, are disposable and need to be properly disposed of after use. One end of perfusion catheter 2 (3) is passed through the inside of sleeve 1 (10) and sleeve 2 (11), and the fixing clip 12 and sliding clip 13 inside are pushed open. Under the action of external force, the fixing clip 12 and sliding clip 13 are fitted and fixed onto perfusion catheter 2 (3). One end of perfusion catheter 1 (2) is inserted into the input end of the concave-convex part 6 through its end clip 5, so that the protruding structure of clip 5 fits and engages with the inner wall of the concave-convex part 6 at the input end of the concave-convex part 6 for fixation. During perfusion, the perfusion fluid enters through perfusion conduit 2 3 and passes sequentially through transparent cylinder 7, perfusion conduit 1 2, and perfusion main tube assembly 1. As the fluid passes through transparent cylinder 7, it is blocked by the hydrophobic microporous filter membrane 8 inside. After passing through the hydrophobic microporous filter membrane 8, tiny air bubbles and air in the perfusion fluid are trapped. The air-free perfusion fluid is then injected into the pulmonary artery trunk through perfusion main tube assembly 1. Please see the appendix Figure 3 Appendix Figure 4 and attached Figure 7 The chassis 9 has a sleeve 10 fixedly connected to one end and a sleeve 2 11 at the other end. Sleeves 10 and 2 11 are connected on adjacent sides via a connecting shaft to change the relative angle between the sleeves 10 and 2 11. Multiple fixed locking sleeves 12 are fixedly connected to the inner wall of sleeve 10. Sleeve 2 11 has a sliding locking sleeve 13 connected to its interior via a traction assembly. Both the fixed locking sleeves 12 and the sliding locking sleeves 13 are fitted onto the outer wall of the infusion conduit 2 3. The connecting shaft includes two connecting shafts 15, one of which is fixedly connected to sleeve 10, and the other is fixedly connected to sleeve 2 11. 1. Fixed connection: The two connecting shafts 15 are rotatably connected on their adjacent sides. An inner shaft 16 slides vertically inside the top connecting shaft 15. A spline shaft 17 is fixedly connected to the bottom side of the inner shaft 16. A spline groove is opened in the center of the bottom connecting shaft 15. The spline shaft 17 is inserted into the inside of the spline groove. The tooth density of the inner wall of the spline groove is greater than the tooth density of the outer wall of the spline shaft 17, so that the spline shaft 17 can be inserted into the inside of the spline groove at multiple angles. The spline shaft 17 is made of magnet, and the connecting shaft 15 is made of iron. The spline shaft 17 and the spline groove are magnetically attracted to each other, so that they are not easy to separate under non-external force factors, so as to maintain the limit and fixation. Specifically, both the fixed clamping sleeve 12 and the sliding clamping sleeve 13 are made of spring steel, possessing sufficient elasticity and deformation capacity, enabling them to clamp and fix the second irrigation catheter 3. The textured rubber pads attached to their inner walls increase friction with the catheter body, thus preventing slippage of the second irrigation catheter 3. Before irrigation, referring to the surgeon's position, the inner shaft 16 is lifted, causing the spline shaft 17 on the bottom side of the inner shaft 16 to disengage from the spline groove. This releases the rotational lock of the connecting shaft 15 connected to the inner shaft 16 on another connecting shaft 15, allowing the connecting shaft 15 connected to the second sleeve 11 to rotate. Simultaneously, this causes the connected sleeve 11, along with the structure including the sliding clamping sleeve 13, to rotate, causing the portion of the second irrigation catheter 3 clamped and fixed by the sliding clamping sleeve 13 to bend, so that the body of the second irrigation catheter 3 faces the surgeon's position. Then, the inner shaft 16 is reset, and the spline shaft 17 is reinserted into the spline groove, thereby fixing the rotation angle of the two connecting shafts 15 and performing the grouting work.

[0024] Please see the appendix Figure 4 -Appendix Figure 6 The traction assembly includes a groove formed on the inner wall of the sleeve 11. The two ends of the bottom side of the sliding snap sleeve 13 are slidably connected to the sleeve 11 through the groove. A guide post 14 is fixedly connected to the middle of the bottom side of the sliding snap sleeve 13. The guide post 14 penetrates the bottom side of the sleeve 11. A guide groove is formed on the bottom side of the chassis 9. The bottom end of the guide post 14 is located inside the guide groove. During the rotation of sleeve 2 11, the guide post 14 on the bottom side of the sliding snap sleeve 13 inside it is displaced due to the rotation of sleeve 2 11. During this displacement, the guide post 14 on the bottom side of the base plate 9 also moves within the guide groove and is pulled by the guide groove, causing it to move in tandem with the sliding snap sleeve 13 within sleeve 2 11. This pulls on the part of the infusion catheter 2 3 that it holds and fixes, increasing the length of the bent part of the infusion catheter 2 3. This prevents the bent part of the infusion catheter 2 3 from being excessively bent, twisted, or folded, allowing it to bend naturally. If this angle is opposite to the operator's position, the infusion catheter 2 3 is rotated 180° on the transparent cylinder 7, changing the bending direction of the infusion catheter 2 3 again until the infusion catheter 2 3 faces the operator. This allows for flexible adjustment of the direction of the infusion tube, preventing the blood vessel from being stretched, twisted, or folded, thereby improving the stability of the infusion flow and pressure. This design significantly improves the ease of operation and the matching degree of the infusion posture, and improves the accuracy and reliability of the overall infusion system.

[0025] Based on the aforementioned arterial perfusion catheter for extracorporeal lung perfusion in small animals, as another aspect of this application, an extracorporeal lung perfusion surgical method for pulmonary artery perfusion in small animals includes the following steps: Step 1: Unseal the infusion conduit 1 (2) and infusion conduit 2 (3). Pass infusion conduit 2 (3) through sleeve 1 (10) and sleeve 2 (11), and secure the locking sleeve 12 and sliding locking sleeve 13 onto infusion conduit 2 (3). Connect and secure infusion conduit 1 (2) to the concave-convex part 6 via the locking tube 5. Step 2: Insert the cone-shaped insertion tip 4 of the perfusion main tube group 1 into the pulmonary artery trunk of a mouse or rat. The concave and convex part 6 protrudes along the blood vessel wall. Use a ligature to wrap and knot the concave part 6 to fix the pulmonary artery trunk. Step 3: Lift the inner shaft 16 to release the rotation lock, and rotate the sleeve 11 to adjust the orientation of the irrigation catheter 3 so that it points towards the surgeon. The guide post 14 and guide groove work together to prevent excessive bending or twisting of the catheter. Step 4: Reset the inner shaft 16 so that the spline shaft 17 can be reinserted into the spline groove, and fix the rotation angle of the two connecting shafts 15. Step 5: The infusion fluid enters from infusion conduit 2 3, passing sequentially through transparent cylinder 7, infusion conduit 1 2, and main infusion tube assembly 1. In transparent cylinder 7, a hydrophobic microporous filter membrane 8 removes tiny air bubbles and air from the infusion fluid. Step 6: The perfusion fluid, after removing air bubbles, is injected into the main pulmonary artery through perfusion main tube group 1 to complete the perfusion process; Step 7: Restore the surgical area, dispose of experimental waste, and perform post-experiment disinfection and cleaning.

[0026] 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. An arterial perfusion catheter for extracorporeal lung perfusion in small animals, characterized in that, include: The perfusion main assembly (1) is U-shaped. A conical insertion cone (4) is fixedly connected to the output end of the perfusion main assembly (1). The top of the conical insertion cone (4) is a smooth cone without sharp edges, for insertion into the pulmonary artery trunk of mice or rats. A rotating part (18) for steering is provided at the bottom of the middle end of the perfusion main assembly (1). Infusion conduit 1 (2), the output end of the infusion conduit 1 (2) is connected to the input end of the infusion main pipe assembly (1), and the input end of the infusion conduit 1 (2) is connected to the infusion conduit 2 (3) through the air filter assembly to access the external infusion liquid supply unit; A chassis (9) is fixedly connected to a sleeve one (10) at one end and a sleeve two (11) is provided at the other end of the chassis (9). The sleeve one (10) and the sleeve two (11) are connected to each other by a connecting shaft to change the relative angle between the sleeve two (11) and the sleeve one (10). A plurality of fixed snap-fit ​​sleeves (12) are fixedly connected to the inner wall of the sleeve one (10). The inside of the sleeve two (11) is connected to a sliding snap-fit ​​sleeve (13) through a traction assembly. The fixed snap-fit ​​sleeves (12) and the sliding snap-fit ​​sleeves (13) are both sleeved on the outer wall of the infusion conduit two (3).

2. The arterial perfusion catheter for extracorporeal lung perfusion in small animals according to claim 1, characterized in that, The infusion main tube assembly (1) is provided with a concave-convex part (6) at both the input and output ends. One of the concave-convex parts (6) is located on the bottom side of the conical insertion cone (4), and the inner wall of the other concave-convex part (6) is engaged with a retaining tube (5). The outer wall of the retaining tube (5) is in contact with the inner wall of the concave-convex part (6), and the input end of the retaining tube (5) is fixedly connected to the output end of the infusion conduit (2).

3. The arterial perfusion catheter for extracorporeal lung perfusion in small animals according to claim 1, characterized in that, The air filtration assembly includes a transparent cylinder (7), one end of which is rotatably connected to and communicates with an infusion conduit (2), and the other end of which is rotatably connected to and communicates with an infusion conduit (3). The inner wall of the transparent cylinder (7) is equipped with a hydrophobic microporous filter membrane (8) for actively blocking and removing tiny air bubbles in the infusion fluid.

4. The arterial perfusion catheter for extracorporeal lung perfusion in small animals according to claim 3, characterized in that, The hydrophobic microporous filter membrane (8) has a pore size of 0.22 to 0.45 μm.

5. The arterial perfusion catheter for extracorporeal lung perfusion in small animals according to claim 1, characterized in that, The connecting shaft includes two connecting shafts (15), one of which is fixedly connected to sleeve one (10), and the other is fixedly connected to sleeve two (11). The two connecting shafts (15) are connected by rotation on their adjacent sides. An inner shaft (16) slides vertically inside the top connecting shaft (15). A spline shaft (17) is fixedly connected to the bottom side of the inner shaft (16). A spline groove is opened in the center of the bottom connecting shaft (15), and the spline shaft (17) is inserted into the spline groove.

6. The arterial perfusion catheter for extracorporeal lung perfusion in small animals according to claim 5, characterized in that, The inner wall tooth density of the spline groove is greater than the outer tooth density of the spline shaft (17), so that the spline shaft (17) can be inserted into the spline groove at multiple angles. The spline shaft (17) is made of magnet, and the connecting shaft (15) is made of iron. The spline shaft (17) is magnetically attracted to the spline groove.

7. The arterial perfusion catheter for extracorporeal lung perfusion in small animals according to claim 1, characterized in that, The traction assembly includes a groove formed on the inner wall of the sleeve two (11). The two ends of the bottom side of the sliding snap sleeve (13) are slidably connected to the sleeve two (11) through the groove. A guide post (14) is fixedly connected to the middle of the bottom side of the sliding snap sleeve (13). The guide post (14) penetrates the bottom side of the sleeve two (11). A guide groove is formed on the bottom side of the chassis (9). The bottom end of the guide post (14) is located inside the guide groove.

8. A surgical method for extracorporeal lung perfusion in small animals, using an arterial perfusion catheter for extracorporeal lung perfusion in small animals as described in any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1: Unseal infusion conduit 1 (2) and infusion conduit 2 (3), pass infusion conduit 2 (3) through sleeve 1 (10) and sleeve 2 (11), and fix the snap-fit ​​sleeve (12) and sliding snap-fit ​​sleeve (13) on infusion conduit 2 (3). Connect and fix infusion conduit 1 (2) to the concave-convex part (6) through snap-fit ​​tube (5); Step 2: Insert the cone-shaped insertion tip (4) of the perfusion main tube group (1) into the main trunk of the pulmonary artery of a mouse or rat. The concave and convex part (6) protrudes along the blood vessel wall. Use a ligature to wrap and tie the concave part (6) to fix the main trunk of the pulmonary artery. Step 3: Lift the inner shaft (16) to release the rotation lock, and rotate the sleeve two (11) to adjust the orientation of the irrigation catheter two (3) so that it points towards the surgeon. The guide post (14) and guide groove work together to prevent excessive bending or twisting of the catheter. Step 4: Reset the inner shaft (16) so that the spline shaft (17) can be reinserted into the spline groove, and fix the rotation angle of the two connecting shafts (15); Step 5: The infusion fluid enters from infusion conduit 2 (3) and passes sequentially through the transparent cylinder (7), infusion conduit 1 (2), and the main infusion tube assembly (1). In the transparent cylinder (7), a hydrophobic microporous filter membrane (8) removes tiny air bubbles and air from the infusion fluid; Step 6: The perfusion fluid with air bubbles removed is injected into the pulmonary artery trunk through the perfusion main tube group (1) to complete the perfusion process; Step 7: Restore the surgical area, dispose of experimental waste, and perform post-experiment disinfection and cleaning.

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