Organ perfusion device

Abstract

This application discloses an organ perfusion device, including a first container, a second container, an oxygenation module, a perfusion conduit, a heating module, a pressure module, and a main control module. The perfusion conduit includes a first flow path, a second flow path, a third flow path, and a cannulation assembly. One end of the first flow path is connected to the first container, and the other end is connected to the arterial end of the isolated organ through the cannulation assembly. One end of the second flow path is connected to the venous end of the isolated organ through the cannulation assembly, and the other end is connected to the second container. The cannulation assembly is connected to the first and second containers through the first, second, and third flow paths, forming a closed perfusion circulation loop to achieve uninterrupted blood flow perfusion during organ acquisition, transfer, and implantation. The device also includes a main control module, a pressure module, and a heating module, which can monitor the pressure and temperature during the perfusion process in real time and adjust the working state of the perfusion device in real time through the main control module to maintain the stability of the perfusion process.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to an organ perfusion device. Background Technology

[0002] Organ transplantation is one of the most effective treatments for patients with end-stage organ failure. In traditional organ transplantation procedures, such as liver and kidney transplantation, the organ undergoes multiple stages after being removed from the donor, including irrigation, cryopreservation, transportation, and implantation. During this process, cold ischemia and warm ischemia phases are unavoidable. During ischemia, organ cells experience energy depletion and ion pump imbalance due to anaerobic metabolism. When blood flow is restored after implantation, ischemia-reperfusion injury (IRI) occurs. Normative mechanical perfusion (NMP) technology, with its continuous oxygen supply, significantly improves the occurrence of IRI, but it is still difficult to completely avoid ischemic damage that occurs during organ acquisition and recurrent ischemia-reperfusion injury (IRI) during transplantation. To address this, researchers proposed the new concept of "Ischemia-Free Organ Transplantation" (IFOT), and specifically, IFOT-based ischemia-free liver transplantation (IFLT) and ischemia-free kidney transplantation (IFKT) for liver and kidney transplantation, respectively. IFKT involves establishing a perfusion circuit between the renal artery and vein on the donor side and the NMP device, ensuring that the donor kidney maintains oxygenated blood flow throughout the entire process of acquisition, preservation, and recipient implantation, thereby avoiding the cold and warm ischemia phases present in traditional kidney transplantation.

[0003] In recent years, small animal organ perfusion models such as mice, rats and rabbits have also been used to simulate ischemic organ transplantation, especially ischemic kidney transplantation. However, there are many limitations in the simulation application, including: (1) Existing animal NMP models usually present a pattern of "one ischemia, multiple reperfusions" or even "two ischemias, two reperfusions", which leads to the damage pattern of organs not matching the damage pattern in clinical IFKT. Animal experimental results have significant deviations when extrapolating to the clinical IFOT / IFKT scenario, which is not conducive to systematically evaluating the true protective effect and mechanism of action of ischemic free technology; (2) In vivo cannulation of blood vessels is difficult and easy to damage: The cannulation components in the existing small animal perfusion system are mostly ordinary metal needles, plastic catheters or universal catheter connectors. Their structure, rigidity and size are adapted to the ex vivo blood vessels, rather than small animal blood vessels that are still in the body and still bear part of the natural blood flow. If directly applied to the IFKT model, it is easy to cause damage to the blood vessel wall, bleeding or insecure cannulation. (3) Lack of dedicated cannulation components and tubing structures for establishing perfusion circuits in vivo: Small animals have small-diameter and thin-walled blood vessels that are easily damaged. Ordinary sharp needles or large-diameter catheters can easily puncture the vessels, leading to blood loss or even experimental failure, making it difficult to complete stable cannulation without interrupting blood flow. Due to the above reasons, it is difficult to construct a true small animal IFOT model in current small animal experiments, and it is impossible to truly reproduce the continuous blood flow surgical process and physiological hemodynamic environment of clinical IFOT at the small animal level. Summary of the Invention

[0004] This application aims to at least address one of the aforementioned technical problems existing in the prior art. Therefore, the purpose of this application is to provide an organ perfusion device that solves the problem that existing small animal organ perfusion devices lack dedicated cannulation components and tubing structures for establishing perfusion circuits in vivo, thus making it impossible to construct an IFOT model.

[0005] To achieve the above objectives, the technical solution adopted in this application is as follows: An organ perfusion device, comprising: The first container is used to store the infusion fluid; The second container is used to store excised organs; An oxygenation module is used to provide oxygen to the perfusion fluid; The perfusion tubing includes a first flow path, a second flow path, a third flow path, and a cannulation assembly. One end of the first flow path is connected to the first container, and the other end is connected to the arterial end of the isolated organ through the cannulation assembly. One end of the second flow path is connected to the venous end of the isolated organ through the cannulation assembly, and the other end is connected to the second container. The third flow path is used to connect the first container and the second container to form a circulation loop. A heating module is used to heat the infusion fluid and monitor the temperature of the infusion fluid; A pressure module, located in the first flow path, is used to monitor the infusion pressure of the infusion fluid; The main control module, which is connected to the pressure module, is used to collect pressure and other parameters during the infusion process, evaluate the infusion status based on the collected parameters, and adjust the infusion process in a timely manner.

[0006] According to some embodiments of this application, the cannulation assembly includes a cannulation body and an extension tube connected in sequence. One end of the cannulation body is provided with a rounded structure for connection with the excised organ, and the other end is connected to one end of the extension tube. The other end of the extension tube is detachably connected to the first flow path or the second flow path.

[0007] According to some embodiments of this application, the cannula assembly further includes a flexible connecting section, one end of which is connected to the cannula body and the other end of which is connected to the extension tube, and the length of the flexible connecting section is 5mm to 10mm.

[0008] According to some embodiments of this application, a protruding structure is provided at the connection between the cannula body and the flexible connecting section, and the protruding structure is used to ensure the sealing of the cannula body.

[0009] According to some embodiments of this application, the heating module includes a heating element and a plurality of temperature sensors. The heating element is disposed on the first flow path and is used to heat the filling fluid. At least three temperature sensors are provided and are used to monitor the temperature of the filling fluid in the first flow path, the first container, and the second container.

[0010] According to some embodiments of this application, the pressure module includes an adjustable speed pump body and a pressure sensor. The first container is connected to the first flow path through the adjustable speed pump body. The adjustable speed pump body is used to provide infusion power. The pressure sensor is located on the first flow path and is used to monitor the pressure of the infusion pipeline.

[0011] According to some embodiments of this application, the organ perfusion device further includes an exhaust assembly disposed in the first flow path to prevent air bubbles from entering the vascular system of the isolated organ.

[0012] According to some embodiments of this application, the second container includes a shell and a fluid structure and a filter structure disposed inside the shell. The fluid structure is used to guide the perfusion fluid to flow uniformly within the shell, and the filter structure is located above the fluid structure for placing the excised organ and for filtering tissue fragments or impurities generated during the perfusion process to prevent backflow into the circulation loop.

[0013] According to some embodiments of this application, the filter structure is detachably connected to the housing, and the filter structure is provided with filter holes, the diameter of which is 50μm to 500μm.

[0014] According to some embodiments of this application, the main control module includes a control unit, and a data acquisition module, an early warning module, and a display module connected to the control unit. The data acquisition module is used to acquire parameters during the perfusion process, the display module is used to display the parameters, the early warning module is used to generate an early warning signal and send it to the control unit when the parameters meet preset abnormal conditions, and the control unit is used to receive the early warning signal and adjust the working state of the organ perfusion device accordingly based on the early warning signal.

[0015] The beneficial effects of this application are: The perfusion device of this application establishes a closed perfusion loop by setting a cannulation assembly in the perfusion tubing, which is connected to the arterial and venous ends of the excised organ, respectively. The cannulation assembly is connected to a first container and a second container through a first flow path, a second flow path, and a third flow path, thereby establishing an in vivo-extracorporeal circulation perfusion system with the donor to achieve uninterrupted blood flow perfusion during organ acquisition, transfer, and implantation. The perfusion device is also equipped with a main control module, a pressure module, and a heating module, which can monitor the pressure and temperature during the perfusion process in real time and adjust the working state of the perfusion device in real time through the main control module to maintain the stability of the perfusion process.

[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0017] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the organ perfusion device structure of this application.

[0018] Figure 2 This is a schematic diagram of the internal structure of the second container.

[0019] Figure 3 This is a schematic diagram of the cannulation assembly structure.

[0020] Figure 4 This is a flowchart of the perfusion method using the organ perfusion device of this application.

[0021] Figure 5 This is a schematic diagram of the donor's abdominal aorta and inferior vena cava cannulation and the in vivo-extracorporeal perfusion circuit.

[0022] Figure 6This is a schematic diagram of the connection between the donor and the cannulation assembly.

[0023] Figure 7 This is a schematic diagram of donor and recipient transplantation.

[0024] Figure 8 It is the curve of change in injection resistance.

[0025] Figure 9 This is a diagram illustrating urine production during perfusion.

[0026] Figure 10 This is a graph showing the change in urine production over time during perfusion.

[0027] Figure 11 This is a comparison chart of NMP and the organ perfusion method of the embodiments of this application.

[0028] Figure 12 This is a schematic diagram comparing the amount of urine produced by the receptors on the first day after NMP and IFKT surgery.

[0029] Figure 13 This is a schematic diagram comparing the creatinine produced by receptors on the first day after NMP and IFKT surgery.

[0030] Figure 14 This is a schematic diagram comparing the blood urea nitrogen produced by receptors on the first day after NMP and IFKT surgery.

[0031] Figure label: 100. First container; 200. Second container; 210. Shell; 220. Cover; 230. Inlet; 240. Outlet; 250. First sensor interface; 260. Infusion fluid circulation interface; 270. Fluid structure; 280. Filter structure; 300. Oxygenation module; 400. Infusion pipeline; 410. First flow path; 411. First interface; 412. Second interface; 413. Third interface; 414. Fourth interface; 415. Third clamping point; 416. T-connector; 4161. Sensor interface; 420. Second flow path Path; 421, Fourth clamping point; 430, Third flow path; 440, Cannulation assembly; 441, Cannulation body; 4411, Rounded structure; 4412, Scale; 442, Extension tube; 443, Flexible connecting section; 444, Protruding structure; 445, Luer lock connector; 500, Ex vivo organ; 510, Abdominal aorta; 511, First clamping point; 520, Inferior vena cava; 521, Second clamping point; 600, Main control module; 700, Heating element; 800, Temperature sensor; 900, Pressure sensor; 1000, Adjustable speed pump body. Detailed Implementation

[0032] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0033] In the description of this application, it should be understood that if directional descriptions are involved, such as up, down, front, back, left, right, etc., indicating the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings, it is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0034] In the description of this application, if words such as several, greater than, less than, exceeding, above, below, or within appear, "several" means one or more, "more than" means two or more, "greater than," "less than," "exceeding," etc. are understood to exclude the number itself, and "above," "below," "within," etc. are understood to include the number itself.

[0035] In the description of this application, the use of terms such as "first" and "second" is for the purpose of distinguishing technical features only, and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0036] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0037] Reference Figures 1 to 14 The following are specific embodiments of this application.

[0038] Depend on Figure 1 As shown, this application provides an organ perfusion device, including a first container 100, a second container 200, an oxygenation module 300, a perfusion pipeline 400, a heating module, a pressure module, and a main control module 600. The first container 100 is used to store perfusion fluid; the second container 200 is used to store excised organs; and the oxygenation module 300 is used to provide oxygen to the perfusion fluid. The perfusion tubing 400 includes a first flow path 410, a second flow path 420, a third flow path 430, and a cannulation assembly 440. One end of the first flow path 410 is connected to the first container 100, and the other end is connected to the arterial end of the isolated organ 500 via the cannulation assembly 440. One end of the second flow path 420 is connected to the venous end of the isolated organ 500 via the cannulation assembly 440, and the other end is connected to the second container 200. The third flow path 430 is used to connect the first container 100 and the second container 200 to form a circulation loop.

[0039] Depend on Figure 1 As shown, the first flow path 410 is located on the left side of the isolated organ 500, and the second flow path 420 is located on the right side of the isolated organ 500.

[0040] The heating module is used to heat the injection fluid and monitor its temperature.

[0041] The pressure module is located on the first flow path 410 and is used to provide infusion power and monitor the infusion pressure of the infusion fluid. The main control module 600 is connected to the pressure module and is used to collect pressure and other parameters during the infusion process, evaluate the infusion status based on the collected parameters, and adjust the infusion process in a timely manner.

[0042] The perfusion device of this application establishes a closed perfusion loop by setting a cannulation assembly in the perfusion tubing, which is connected to the arterial and venous ends of the excised organ, respectively. The cannulation assembly is connected to a first container and a second container through a first flow path, a second flow path, and a third flow path, thereby establishing an in vivo-extracorporeal circulation perfusion system with the donor to achieve uninterrupted blood flow perfusion during organ acquisition, transfer, and implantation. The perfusion device is also equipped with a main control module, a pressure module, and a heating module, which can monitor the pressure and temperature during the perfusion process in real time and adjust the working state of the perfusion device in real time through the main control module to maintain the stability of the perfusion process.

[0043] Furthermore, the first container 100 is connected to the monitoring and control module, and the first container 100 is provided with an outlet, which is connected to the first flow path.

[0044] The first flow path 410, the second flow path 420, and the third flow path 430 are all flexible tubes. The flexible tubes are made of medical-grade silicone tubing, polyurethane tubing, silicone with a hardness of Shore A 60, or polyurethane with a hardness of Shore A 70. They can balance flexibility and pressure resistance, ensuring that they have sufficient flexibility while having high pressure resistance, and can withstand working pressure in the range of 0 mmHg to 150 mmHg without significant deformation, rupture, or leakage.

[0045] In some embodiments, heating bands (not shown) are fitted onto the outer wall portions of the first flow path 410, the second flow path 420, and the third flow path 430. The heating bands are used to reduce the temperature loss of the injection fluid during the transmission process of the injection pipeline 400, so that the temperature of the injection fluid entering the second container 200 is closer to the set value, which is beneficial to maintaining the temperature stability of the entire injection device.

[0046] Alternatively, the heating belt can be replaced with a constant temperature water bath to cover the injection pipeline.

[0047] Meanwhile, along the blood flow direction, the first flow path 410 is provided with a first interface 411, a second interface 412, a third interface 413, and a fourth interface 414. The first interface 411 is used to connect to the temperature sensor 800. The second interface 412 and the third interface 413 are respectively located on the left and right sides of the oxygenation module 300 and are used to connect to the exhaust assembly (not shown). The exhaust assembly is used to prevent air bubbles from entering the vascular system of the isolated organ. The fourth interface 414 is used to connect to the pressure sensor 900.

[0048] The first interface 411, the second interface 412, the third interface 413 and the fourth interface 414 are tee threaded connectors or threaded sensor interfaces to facilitate the installation and removal of the sensor. By setting the first interface 411, the second interface 412, the third interface 413 and the fourth interface 414, the pressure and temperature of the injection fluid during the injection process can be monitored in real time.

[0049] In some embodiments, the venting assembly is an venting bladder, venting port, one-way venting valve, gas separator, or vertical riser pipe, used to vent air and air bubbles in the first flow path 410 before and during perfusion, to prevent air and air bubbles from entering the organ's vascular system and causing air embolism or affecting perfusion stability.

[0050] Furthermore, the first flow path 410 is equipped with a bubble detection module, which is connected to the main control module to monitor whether there are bubbles in the first flow path 410, so as to ensure the stability of the injection.

[0051] Depend on Figure 2As shown, in some embodiments, the second container 200 includes a shell 210, a cover 220 disposed on the shell 210, and an inlet 230, an outlet 240, a first sensor interface 250, and an infusion fluid circulation interface 260 disposed on both sides of the shell 210. There are two outlets 240, one corresponding to the inlet 230 and disposed on both sides of the outer wall of the shell 210, and the other located below the outlet 240. The first sensor interface 250 is disposed near the bottom of the shell 210 and is used to connect to a temperature sensor or a pressure sensor. The temperature sensor or pressure sensor is in direct contact with the liquid inside the shell or is disposed on the inner wall of the shell 210, and can reflect the temperature or pressure around the excised organ 500 in real time and provide feedback signals to the main control module.

[0052] The infusion fluid circulation interface 260 is used to communicate with the first container 100 through the third flow path 430.

[0053] In some embodiments, the housing 210 is made of a transparent or translucent biocompatible material, such as polycarbonate, acrylic, or other medical-grade engineering plastics, to allow operators to visually observe the color, volume, and surface pulsation of the isolated organ 500 during perfusion. A reliable seal is achieved between the cap 220 and the housing 210 via a sealing ring, snap-fit, thread, or other sealing structure, thereby creating a relatively closed perfusion environment, reducing the risk of contamination and minimizing perfusion fluid evaporation.

[0054] Furthermore, the housing 210 can also be made of metal and have a transparent viewing window.

[0055] In some embodiments, the housing 210 is further provided with a fluid structure 270 and a filter structure 280. The fluid structure 270 is located at the bottom of the housing 210 and is one of an annular diversion channel, a mesh diversion channel, a guide plate, or a protrusion array. It is used to guide the perfusion fluid to form a uniform flow state within the housing 210, avoid local impact flow or stagnant dead zones, and ensure that the surface of the excised organ 500 obtains a uniform liquid flushing and heat exchange environment.

[0056] The filter structure 280 is located above the fluid structure 270. The filter structure 280 is a membrane structure or a filter screen structure. The membrane structure is made of medical-grade metal wire mesh, polymer fiber mesh, or other biocompatible filter media, and is laid in a sheet or tray shape at the bottom of the housing 210 or near the perfusion fluid circulation interface 260. The pore size of the filter structure 280 ranges from 50μm to 500μm, and is used to intercept blood clots, tissue fragments, and other solid particles formed during perfusion, preventing them from flowing back into the pipeline and pressure module with the perfusion fluid, thus reducing the risk of pipeline blockage and pump damage. Simultaneously, the filter structure 280 also serves as a support platform for the isolated organ 500, allowing the isolated organ 500 to remain in a basically natural and relaxed state within the second container 200, avoiding direct contact with the hard bottom and causing localized pressure. The filter structure 280 is preferably detachable, facilitating complete removal for cleaning or replacement after perfusion.

[0057] The fluid structure 270 can also be a porous tray or a perforated bracket, and the filter structure 280 can be a disposable filter membrane box or a replaceable filter element structure.

[0058] Depend on Figure 3 As shown, in some embodiments, the cannulation assembly 440 includes a cannulation body 441 and an extension tube 442 connected in sequence. One end of the cannulation body 441 is provided with a blunt structure 4411 for connection with the ex vivo organ 500, and the other end is connected to one end of the extension tube 442. The other end of the extension tube 442 is detachably connected to a first flow path 410 or a second flow path 420.

[0059] The blunt structure 4411 is fixedly connected to the cannula body 441 or is an integrally formed structure.

[0060] Preferably, the blunt-tipped structure 4411 is a 15G-specification blunt-tipped coarse needle structure, which can meet the perfusion throughput requirements while reducing the risk of cutting or tearing the vascular endothelium of small animals during in vivo cannulation, making it suitable for in vivo operations that do not interrupt blood flow. The cannula body 441 is a 15G-specification tube with an inner diameter of 1.8 mm and a wall thickness of 0.8 mm to ensure that it is not easily collapsed within the working pressure range of 0 mmHg to 150 mmHg, while also having sufficient flexibility to facilitate operation in the narrow surgical field of small animals.

[0061] The inner diameter of the hose is matched with the pressure module, interface, and cannulation assembly to obtain a stable infusion flow rate and a reasonable flow velocity.

[0062] Furthermore, the cannulation assembly 440 also includes a flexible connecting section 443, one end of which is connected to the cannulation body 441 and the other end is connected to the extension tube 442. The flexible connecting section 443 is used to reinforce the connection between the cannulation body 441 and the extension tube 442, reducing the risk of loosening, breakage, or leakage during cannulation pulling, positioning, or repeated minor bending.

[0063] The cannula assembly 440 and the flexible connecting section 443 are either fixedly connected or integrally formed. The flexible connecting section 443 and the extension tube 442 are fixedly connected, while the other end of the extension tube 442 is detachably connected to the first flow path 410 or the second flow path 420. Detachable connections include, but are not limited to, connections via Luer lock connectors 445, ferrule connections, and quick-connect connectors via threads or snaps. Fixed connections include, but are not limited to, heat-fusion connections, adhesive connections, interference fit connections, and connections reinforced after sleeve fitting.

[0064] Furthermore, the Luer lock connector 445 can be replaced with other rotary locking connectors, with the interface for connecting arterial and venous cannulas set with a tapered connector adapted to the size of the artery and vein, ensuring smooth insertion and removal as well as a tight seal.

[0065] In some embodiments, the outer wall of the cannula body 441 is provided with a scale 4412 or a positioning mark to facilitate control of the insertion depth, reduce differences between different operators, and improve repeatability. At the same time, a protruding structure 444 is provided at the connection between the cannula body 441 and the flexible connecting section 443. The protruding structure 444 is one of a thickened section, a flange, or a limiting shoulder, in order to facilitate suture wrapping and fixation, and improve the anti-slipping ability and sealing stability of the cannula body 441 during long-term infusion.

[0066] Preferably, the extension tube 442 is a silicone or polyurethane flexible tube with an inner diameter of 1.8 mm, an outer diameter of 3 mm, and a length of 30-50 cm. Its hardness matches that of the cannula body 441 to ensure that no significant deformation occurs during long-term use. In addition to extending the length of the perfusion tubing, the extension tube 442 also allows the cannula end to remain connected to the perfusion device without reconnection when the donor organ is transferred between the donor site, the second container 200, and the recipient kidney bed.

[0067] In some embodiments, the length of the flexible connecting section 443 is 5mm to 10mm, which has the following functions: First, it facilitates the connection, clamping, or locking of the end of the extension tube 442 with the Luer lock connector or other interface components, preventing the flexible connecting section 443 from being too close to the end of the extension tube 442 and affecting the assembly seal. Second, it retains a small flexible buffer zone, allowing the end of the extension tube 442 to still have a certain local bending capacity after connection, thereby reducing stress concentration between the flexible connecting section 443 and the extension tube 442 and reducing the risk of leakage or detachment caused by bending. Third, it facilitates the operator to grasp, screw, and adjust the direction in a limited space during operation, improving installation convenience and repeatability. Among these, 5mm to 10mm is a preferred range that balances structural strength and operational convenience: if the distance is too small, the installation space for the extension tube 442 will be insufficient, and the flexible buffering effect will be poor; if the distance is too large, the reinforcing section will be too far from the stress point, and the reinforcement effect will decrease.

[0068] The infusion tubing 400 achieves a balance between flexibility and pressure resistance through the above design, which facilitates its placement and operation in confined animal surgical areas while ensuring unobstructed and reliable flow during long-term infusion.

[0069] Furthermore, the infusion tubing 400 in this application is designed as a disposable consumable to ensure biological safety, avoid cross-contamination, reduce cleaning components, and simplify the operation process.

[0070] In some embodiments, the organ perfusion device further includes a heating module, which includes a heating element 700 and a plurality of temperature sensors 800. The heating element 700 is disposed on the first flow path 410 for heating the perfusion fluid. At least three temperature sensors 800 are provided and are respectively disposed near the first flow path 410, the first container 100 and the second container 200 for monitoring the temperature of the perfusion fluid.

[0071] Specifically, the heating element 700 is a resistance heating plate, heating rod, or circulating water bath heater, which is located at the bottom of the first container 100, on the outer wall of the shell 210, or in an external water bath, and is used to heat the filling liquid in the second container 200.

[0072] Simultaneously, multiple temperature sensors 800 form a multi-point temperature measurement system, connected to the temperature control unit (not shown) in the main control module 600. The temperature control unit collects and processes the temperature signals from each measurement point, and uses a proportional-integral-derivative (PID control or fuzzy control) algorithm or a similar closed-loop control strategy to adjust the power output of the heating element 700, keeping the temperature of the perfusion system near a preset value. For example, the perfusion temperature can be set as needed to a range of room temperature, 32℃~34℃, or close to the physiological temperature of 36~37℃, and the steady-state temperature fluctuation can be controlled within a certain error range. To reduce temperature overshoot and fluctuation, the temperature control unit sets a heating rate limit and a high-temperature alarm threshold. When the temperature rises close to the target value, it automatically reduces the heating power and enters a fine adjustment stage to ensure that the perfusion fluid can be quickly raised from room temperature to the target temperature before perfusion and that the temperature is maintained stably for a long time during perfusion, providing a constant temperature control environment for the organ.

[0073] In some embodiments, when the infusion temperature is set to 36–37°C and water bath heating is used, the temperature control unit sets a heating rate limit, for example, 0.1°C / min–0.8°C / min (preferably 0.2°C / min–0.5°C / min); when the temperature approaches the target value, |T When Tset|≤0.5~1.0℃ (preferably ≤0.8℃), it enters the fine adjustment stage and automatically reduces the upper limit of heating power from 70%~100% to 30%~60%, and at |T When Tset|<1℃, the power drops to 10%~25%, and a lower limit for maintaining power can be set, for example, 5%~15%. In addition, a high temperature alarm threshold can be set, and an alarm is triggered when T≥Tset+1.0~2.0℃ (preferably +1.5℃). Furthermore, an absolute threshold can be set to alarm at 39℃~40℃ and trigger protection processing at 41℃~42℃.

[0074] In some embodiments, the pressure module includes an adjustable-speed pump body 1000 and a pressure sensor 900. The first container 100 is connected to the first flow path 410 via the adjustable-speed pump body 1000, which provides infusion power. The adjustable-speed pump body 1000 is a peristaltic pump or a pulse pump. The pressure sensor 900 is used to measure the pressure value in the infusion line in real time.

[0075] Furthermore, constant pressure injection can be achieved by setting a constant flow pump with a pressure limiting valve or a back pressure valve.

[0076] Specifically, the main control module 600 includes a control unit (not shown) and a pump drive circuit (not shown). The pressure sensor 900 is connected to the control unit. The control unit compares the measured real-time pressure with the preset target pressure or target pressure range, calculates the deviation, and generates an adjustment command for the pump speed accordingly. The pump drive circuit receives the control signal output from the control unit and adjusts the speed of the adjustable-speed pump body 1000, ultimately achieving closed-loop control of pressure and speed, maintaining the infusion pressure near the set value or set range.

[0077] In some embodiments, the control unit in this application can implement multiple infusion modes: (1) Constant flow mode: The pump speed of the adjustable speed pump body 1000 is maintained at a fixed value, and the output flow rate is relatively constant, which is suitable for the steady-state injection stage.

[0078] (2) Pulsed flow mode: By periodically changing the pump speed, pulsating flow and pressure fluctuations similar to the physiological cardiac cycle are formed to simulate the hemodynamic environment in the body. Furthermore, the pulsed flow mode can also be achieved through the intermittent opening and closing of the solenoid valve or the alternating output of the dual pumps.

[0079] (3) Multi-stage gradual flow mode: At the beginning of the perfusion, the pump speed and pipeline pressure are gradually increased according to the set pressure rise curve to achieve a smooth transition from low pressure to target pressure; at the end of the perfusion or the transition stage, the pump speed and pressure are gradually reduced according to the preset pressure drop curve to avoid sudden pressure changes from impacting organs.

[0080] Furthermore, the control unit can calculate perfusion resistance based on the relationship between pressure and flow rate, and analyze the trend of resistance changes. When an abnormal increase in perfusion resistance is detected, it can automatically reduce the pump speed or issue an alarm to prevent organ vascular damage caused by excessive perfusion pressure.

[0081] In some embodiments, the oxygenation module 300 is disposed in the first flow path 410, with its inlet connected to the outlet of the adjustable-speed pump body 1000 and its outlet connected to the first flow path 410. It is used to provide sufficient oxygen to the perfusion fluid and remove carbon dioxide in the second-stage perfusion mode to maintain the oxygen metabolism requirements of the isolated organ 500. The oxygenation module 300 is a small membrane oxygenator, such as a hollow fiber membrane oxygenator or a plate membrane oxygenator, or a simplified oxygenation structure using surface aeration or microporous aeration stones, as long as it can maintain the dissolved oxygen level of the perfusion fluid under experimental requirements.

[0082] Specifically, the oxygenation module 300 internally incorporates several hollow fiber membranes or multilayer thin film structures, with one side serving as the permeate fluid flow channel and the other as the gas flow channel. Oxygen diffuses into the permeate fluid and carbon dioxide is expelled from the permeate fluid through the semi-permeable membranes. To improve gas exchange efficiency, the oxygenation module 300 can be designed with a multi-channel flow path structure to ensure sufficient contact area and residence time for the permeate fluid.

[0083] Furthermore, the oxygenation module 300 connects to an oxygen source or an air / oxygen mixture source, adjusting the oxygenation intensity by regulating the gas flow rate, gas pressure, and oxygen concentration. If the system is equipped with a blood gas analyzer or dissolved oxygen sensor, the oxygenator's operating parameters can be adjusted in a closed loop based on the detection results of the perfusion fluid's oxygen partial pressure and saturation, maintaining the oxygen content of the perfusion fluid within a suitable range. When a persistently low oxygen content or abnormal gas supply is detected, the main control module 600 can issue an alarm.

[0084] Meanwhile, the portion of the oxygenation module 300 that contacts the perfusion fluid is preferably made of a biocompatible, temperature- and pressure-resistant material, and an anticoagulant coating may be applied to its inner surface as needed to reduce the risk of thrombosis and hemolysis. The oxygenation module 300 is connected to the first flow path 410 using a standardized connector for easy assembly, disassembly, and sterilization.

[0085] In some embodiments, the main control module 600 further includes a data acquisition module, an early warning module, and a display module. The control unit is connected to the data acquisition module, the early warning module, and the display module, respectively. The data acquisition module is used to acquire and record operating parameters during the infusion process, such as pressure and temperature values, in real time. The data acquisition module includes a multi-channel signal acquisition circuit, an analog-to-digital converter, and a storage unit. The output terminals of the pressure sensor 900 and the temperature sensor 800 are electrically connected to the corresponding input channels of the multi-channel signal acquisition circuit. The output terminal of the multi-channel signal acquisition circuit is connected to the analog-to-digital converter to convert the analog signals from each sensor into digital signals. The output terminal of the analog-to-digital converter is communicatively connected to the control unit. The control unit processes the digital parameters, calculates the infusion resistance in real time (e.g., represented by the pressure / flow rate ratio), and synchronously sends the data such as infusion pressure, flow rate, temperature, and infusion resistance to the display module for real-time presentation. Simultaneously, it stores the data in the storage unit for future retrieval and analysis. The acquisition period is 1 second, corresponding to a sampling frequency of 1 Hz.

[0086] The early warning module dynamically assesses the perfusion status based on collected multi-parameter data, using rule-based judgment and / or machine learning algorithms. The system can preset various abnormal judgment conditions, such as: perfusion pressure continuously exceeding the upper limit or rising sharply in a short period of time; perfusion flow rate continuously below the lower limit or close to zero; perfusion fluid temperature deviating from the set value beyond the allowable range; perfusion resistance showing a continuous upward or abrupt trend; and significantly enhanced bubble detection signal.

[0087] When one or more of the abnormal conditions are met, the early warning module sends an early warning or alarm signal to the control unit, and the infusion device executes corresponding linkage control measures, such as automatically reducing the pump speed of the adjustable speed pump body 1000, temporarily stopping the infusion, issuing an audible and visual alarm, displaying the abnormality type and suggested inspection steps on the display module, and automatically marking and saving the data segments before and after the abnormality for subsequent analysis.

[0088] By setting up a data acquisition module and an early warning module, the perfusion device of this application can realize real-time monitoring and intelligent risk management of the perfusion process, thereby improving the safety and reproducibility of small animal organ perfusion experiments.

[0089] In some embodiments, the display module includes a touch screen, control buttons, interface control software, and a data communication interface. The interface control software generates a graphical user interface. The touch screen is electrically connected to the control unit and receives image data from the interface control software, providing feedback on touch operation signals. The control buttons are connected to the control unit and are used in emergency stops or mode switching. One end of the data communication interface is connected to the control unit for data transmission, and the other end is connected to an external device for data export or remote monitoring.

[0090] The perfusion tubing in this application has been limited and optimized in terms of diameter, wall thickness, and materials, balancing pressure resistance and flexibility to adapt to the limited surgical field of small animals. A standard interface is used to connect the device to the perfusion tubing, ensuring a secure, non-dislodging, and reliable seal under pressure. It also supports modular assembly and rapid replacement of disposable consumables. An venting assembly and heating module are included to eliminate air bubbles in the tubing, reducing the risk of air embolism and blockage. The heating module maintains a constant temperature for the perfusion fluid. The filtration structure works in conjunction with the perfusion tubing to achieve integrated optimization of the ischemia-free transfer pathway from "donor in situ → second container → recipient kidney bed." Through the design of the cannula and extension tube, the perfusion circuit does not need to be disconnected or re-vented during organ repositioning, structurally achieving continuous, uninterrupted perfusion throughout the entire process.

[0091] Depend on Figure 4 As shown, the perfusion method applicable to the organ perfusion device of this application is used in clean environments such as operating rooms. Taking kidney transplantation as an example, the organ perfusion method includes: S100. Constructing the infusion device, preparing and pretreating the infusion fluid, specifically including: S110. Blood Collection: Select blood donor animals, preferably rodents. Use a 24G arterial scavenging needle to puncture the abdominal aorta of the donor animal and collect a certain amount of arterial blood as the oxygen-carrying component of the perfusion fluid. After removing obvious clots from the collected arterial blood through a simple filter or filtration device, mix it with the basal perfusion fluid in a predetermined ratio to form a blood-containing perfusion fluid. The mixing ratio is determined by the different types of perfusion fluid formulations; common ratios of basal perfusion fluid to arterial blood are 1:1 or 5:1.

[0092] S120. Constructing the infusion device, including pre-filling and venting: Connect the infusion pipeline 400 to the first container 100, the second container 200, the oxygenation module 300, the adjustable speed pump body 1000, the first interface 411, the second interface 412, the third interface 413, and the fourth interface 414 according to a predetermined path, and set corresponding sensors and venting components at each interface to construct the infusion device.

[0093] The prepared injection fluid is injected into the injection pipeline 400 and the second container 200. The air and air bubbles in the injection pipeline are discharged through the venting assembly until the liquid in the injection circuit is continuous and there are no obvious air bubbles.

[0094] S130, Temperature Pre-adjustment: The main control module 600 and heating element 700 are started. The temperature control unit sets the target filling temperature or temperature range. At the same time, the heating element 700 works to heat the filling liquid in the second container 200 and the filling liquid in the filling pipeline 400. The temperature is fed back to the temperature control unit through multiple temperature sensors 800. The temperature control unit adjusts the heating power of the heating element 700 so that the temperature of the filling liquid gradually rises to the set target filling temperature or temperature range and remains stable. The temperature control unit enters standby or maintains a constant temperature state for the filling liquid.

[0095] Furthermore, if the outer wall of the injection pipe 400 is equipped with a heating strip, the temperature control unit also controls the processing power of the heating strip.

[0096] If necessary, the oxygenation module 300 can be activated simultaneously to pre-oxygenate the perfusion fluid, so that the perfusion fluid entering the donor body or the second container 200 has a suitable oxygen content.

[0097] S200, Donor perfusion preparation and perfusion reference pressure setting: With the perfusion fluid flow rate close to zero, record the actual arterial pressure range of the donor aorta, and set the perfusion reference pressure based on the actual arterial pressure range, specifically including: S210. Donor Vessel and Ureter Management: Under anesthesia and basic surgical procedures, the abdominal aorta, inferior vena cava, and ureter surrounding the donor rat kidney are dissected to clearly expose the structures in the renal hilum. All relevant branches of the abdominal aorta and inferior vena cava, except for the renal arteries and veins, are ligated or severed to simplify blood supply and return pathways. A ureteral cannula is inserted and fixed at a suitable location below the renal hilum. The ureter is then disconnected, maintaining a patent connection between the ureter and the kidney to facilitate urine drainage or observation during subsequent perfusion.

[0098] S220. Reserved vascular stumps: Select appropriate locations on the abdominal aorta and inferior vena cava to reserve 0.5 cm vascular stumps for subsequent arterial and venous cannulation, which are sufficient to accommodate dedicated renal artery and venous cannulas and facilitate fixation and sealing.

[0099] S230, Arterial pressure measurement and perfusion baseline pressure setting: Use the cannulation assembly 440 to puncture towards the heart at a suitable position in the abdominal aorta. Specifically, insert it into the abdominal aorta or the target artery stump connected to the renal vein through the blunt structure 4411. The other end of the cannulation assembly 440, i.e. the end of the extension tube 442 away from the flexible connection section 443, is connected to the perfusion line 400 through a Luer lock connector, tapered connector or other sealing connector, and the pressure measurement mode of the perfusion device is activated.

[0100] The pressure measurement mode is as follows: when the flow rate in the perfusion line 400 is close to zero or extremely low, the pressure sensor 900 records the actual arterial pressure range of the donor rat abdominal aorta to obtain the upper and lower limits of the pressure. The average value of the upper and lower limits is set as the perfusion reference pressure P0 of the donor and is input or confirmed by the main control module 600 and stored in the control unit for use as the target pressure parameter for subsequent perfusion processes.

[0101] By setting a perfusion reference pressure P0 for each donor based on individual differences, unlike the traditional perfusion method that uses a fixed pressure, it can better simulate the donor's original physiological state and reduce the risk of over- or under-pressure perfusion during the perfusion process.

[0102] S300. Establish the donor in vivo-extracorporeal perfusion circuit and initiate the first-stage perfusion mode, specifically including: S310, Vascular occlusion and transection: by Figure 5 As shown, vascular clamps are set at the first clamping point 511 on the abdominal aorta 510 below the right renal artery and vein of the donor and the second clamping point 521 on the inferior vena cava 520, respectively, to temporarily block the proximal and distal ends. Based on the blockage, the blood vessel is cut at the distal end to form a vascular opening that can be inserted.

[0103] S320. Insertion and fixation of cannulation components: The distal stumps of the abdominal aorta 510 and the inferior vena cava 520 are flushed with heparinized saline, and the two sets of cannulation components 440 are inserted into the distal stumps of the abdominal aorta and the distal stumps of the inferior vena cava, respectively.

[0104] During insertion, the depth and direction of the cannula are adjusted so that the blunt structure 4411 is in the appropriate position, and the cannula assembly 440 is fixed to the corresponding blood vessel wall with sutures to prevent dislodgement or leakage during perfusion. Subsequently, the other end of the cannula assembly, namely the end of the extension tube 442 away from the flexible connecting section 443, is connected to the first flow path 410 and the second flow path 420 of the perfusion device.

[0105] Depend on Figure 6 As shown in the figure, the arrows point to the direction of perfusion fluid flow. The left side is the distal end, i.e., the side with the perfusion device, and the right side is the proximal end, i.e., the side closer to the organ. A third clamping point 415 is provided on the first flow path 410. Before the cannula assembly 440 is firmly connected to the organ, the third clamping point 415 is clamped by a tube clamp to prevent the perfusion fluid from flowing out and causing waste. At the same time, a three-way connector 416 is provided between the third clamping point 415 and the cannula assembly for connecting the first flow path 410, the pressure sensor 900 and the cannula assembly 440. A second sensor interface 4161 is provided for connecting the pressure sensor 900.

[0106] A fourth clamping point 421 is provided on the second flow path 420. Before the cannulation assembly 440 is firmly connected to the organ, the fourth clamping point 421 is clamped by the cannula clamp to prevent the perfusion fluid from flowing out and causing waste.

[0107] S330. Release the vascular clamps and establish the first-stage perfusion mode: After confirming that the cannulation assembly 440 is securely connected to the organ, the first flow path 410 and the second flow path 420, and that the gas in the perfusion tubing 400 has been fully expelled, release the vascular clamps on the first clamping point 511 and the second clamping point 521, as well as the tube clamps on the third clamping point 415 and the fourth clamping point 421, so that the perfusion fluid enters the donor's right renal artery through the first flow path 410 under the drive of the adjustable speed pump body 1000 and returns through the renal vein, thereby entering the first-stage perfusion mode.

[0108] At this time, the control unit controls the speed of the adjustable pump body 1000 according to the preset pressure rise curve, so that the infusion pressure gradually increases from the initial value close to 0, and slowly transitions to the preset infusion reference pressure P0 within a predetermined time.

[0109] Preferably, the value of P0 ranges from 50 mmHg to 80 mmHg, and the temperature of the perfusion fluid ranges from 35℃ to 38℃. The flow rate of the perfusion fluid is automatically matched by the control unit based on feedback from the pressure sensor 900, ensuring that the donor kidney experiences a stable increase in pressure and flow rate during the initial stage of perfusion, avoiding instantaneous high-pressure shocks.

[0110] S400. After the first-stage perfusion mode has been running smoothly, the second-stage perfusion mode is activated: After the first-stage perfusion mode has been running smoothly and the donor organ is connected to the perfusion device, the donor organ is removed from the body and placed into the second container. Then, the second-stage perfusion mode is entered. The perfusion pressure is set with the perfusion reference pressure P0. At the same time, the main control module monitors the parameters during the perfusion process in real time and controls the perfusion device to ensure smooth perfusion operation. Specifically, this includes: S410. Kidney removal and transfer: While ensuring that the cannulation assembly 440 between the abdominal aorta 510 and the inferior vena cava 520 and the organ remains connected and perfused, the remaining tissue connections related to the donor's right kidney are severed, and the right kidney, along with the connected vascular segment and cannula, is removed as a whole and transferred to the filter structure 280 in the second container 200. The cannulation assembly 440 is then connected to the first flow path 410 and the second flow path 420, respectively.

[0111] S420, Initiate the second-stage perfusion mode: After kidney removal, the system transitions to normothermic mechanical perfusion (NMP) mode, also known as the second-stage perfusion mode. The control unit targets the perfusion reference pressure P0 and stabilizes the perfusion pressure within the range of P0 ± 5 mmHg. The temperature control unit adjusts and maintains the perfusion temperature within the range of 35℃ to 38℃, ensuring the kidney is in a perfusion environment close to physiological temperature. The perfusion flow rate is automatically matched to the pressure and perfusion resistance by the speed of the adjustable-speed pump 1000, ensuring that excessive flow does not cause overstretching, while insufficient flow leads to poor perfusion.

[0112] Specifically, the infusion pressure generated by the adjustable-speed pump 1000 at different rotational speeds is transmitted to the pressure sensor 900 for matching. The rotational speed of the adjustable-speed pump 1000 can then be adjusted by regulating a preset pressure value. If the pressure is too high, the pump speed can be reduced; if the pressure is too low, the pump speed can be increased. This matching data is designed and obtained differently for different organs.

[0113] By using the cannulation assembly to measure the upper and lower limits of the donor's true abdominal aortic pressure at zero flow or around zero, and taking the average or representative value as the individualized perfusion reference pressure P0 for the donor; using P0 as the target pressure, a pressure-speed closed-loop control is formed through a pressure sensor and an adjustable speed pump, first smoothly transitioning from low pressure to P0 according to a preset pressure rise curve, and then stabilizing near P0 within a preset fluctuation range in a multi-stage perfusion strategy; based on real-time pressure and flow, perfusion resistance and its changing trend are calculated to identify microcirculatory abnormalities or blockage risks, and protective measures such as flow restriction, pressure reduction and / or alarms are implemented in conjunction to reduce the damage of abnormal pressure fluctuations to organ microcirculation.

[0114] S430, Perfusion Resistance Monitoring and Protection: The acquisition module continuously collects perfusion pressure, flow rate, and temperature data, and calculates perfusion resistance, which can be characterized by the pressure-to-flow ratio. When the control unit detects that the perfusion resistance is continuously increasing or reaches a preset threshold, the perfusion device can automatically reduce the pump speed, appropriately reduce the perfusion pressure, or issue an alarm through the early warning module to implement a low-flow protection strategy to reduce the pressure burden on the renal blood vessels and microcirculation.

[0115] S440, Data Recording: The acquisition module records key parameters such as real-time pressure curves, temperature changes, and perfusion resistance fluctuations. If necessary, operators can mark time points of changes in kidney color, tissue tension, etc., that can be observed by the naked eye on the display module for subsequent analysis of perfusion quality and kidney status.

[0116] S500, Recipient Preparation and Pretreatment: While the donor kidney is kept in the second container 200 with continuous NMP, the recipient animal is prepared accordingly, including: S510. Recipient Kidney Processing: In the recipient animal, the artery and vein of the left kidney are freed and the left kidney is completely removed. The kidney bed is cleaned, and the left ureter is freed and cannulated for fixation.

[0117] S520, Left Renal Vessel Management: The branches of the artery and vein of the left kidney are separated and ligated, preserving the main blood supply and return pathways. The left kidney and ureter are removed at the renal hilum, and at least 0.5 cm of the main trunk of the left renal artery and vein are preserved as interfaces for subsequent arteriovenous anastomosis with the donor kidney.

[0118] S530, Flushing and Pretreatment: The arterial and venous stumps of the left kidney are flushed with heparinized saline to remove residual blood and prevent thrombosis. Meanwhile, the donor kidney continues to receive continuous, ambient-temperature mechanical perfusion within the second container 200, maintaining perfusion pressure and flow within the set range without interruption.

[0119] S600, Donor Implantation and Perfusion Device Unloading: The ex vivo organ under perfusion is implanted into the recipient and vascular anastomosis is completed. When the main control module detects that the flow rate and pressure of the first and second flow paths have decreased to or approached zero, the perfusion device is unloaded, and the end-of-perfusion time point is recorded, including: S610, Donor kidney transplantation to recipient kidney bed: by Figure 7 As shown, the donor's right kidney, which is in a perfusion state, is removed from the second container 200. While maintaining the connection between the donor's right kidney and the perfusion tubing and maintaining perfusion, the donor's right kidney is transferred to the renal bed region of the recipient's left kidney. The kidney position is adjusted so that the arteries and veins of the donor's right kidney are matched with the positions of the arterial and venous stumps that have been reserved by the recipient.

[0120] S620. Vascular Anastomosis: While ensuring perfusion is ongoing and that the donor's right kidney is not significantly ischemic, sequentially perform end-to-end anastomoses between the donor vein and recipient vein stumps, and then between the donor artery and recipient artery stumps. During anastomosis, the perfusion pressure may be temporarily reduced as needed to minimize bleeding in the surgical field (i.e., blood seepage or gushing out within the surgical area) and to reduce the difficulty of the anastomosis. After the anastomosis is completed, gradually restore the perfusion pressure to the set value. After the anastomosis is completed, check the anastomosis site for leakage and perform necessary repairs.

[0121] S630. Vascular Connection and Perfusion Device Unloading: After confirming that the anastomosis is patent and there is no obvious bleeding, slowly loosen the proximal vascular clamps of the recipient's artery and vein, allowing the recipient's systemic circulation to gradually perfuse the donor kidney. As the recipient's blood flows into the donor kidney, the blood supply to the donor kidney gradually transitions from the perfusion device to the recipient's systemic circulation.

[0122] The pressure and acquisition modules of the perfusion device can monitor changes in the perfusion pressure and flow rate of the donor kidney. When the flow rate and pressure in the perfusion device circuit drop to a preset threshold or approach zero, a message such as "Blood flow connection complete" or similar will be displayed on the display interface. At this time, the operator closes the arteriovenous perfusion tubing clamping device, cuts off and removes the arterial and venous cannulation components, achieving complete separation of the perfusion device from the donor kidney.

[0123] S640. Record the end of perfusion time: The acquisition module records the end of perfusion time and related perfusion parameters before and after the procedure, providing objective evidence for subsequent evaluation of ischemia-free transplantation and organ function. Afterwards, ureteral anastomosis and abdominal cavity closure can be performed as needed for the experiment.

[0124] The organ perfusion method in this application, by combining a perfusion device and a main control module, realizes continuous perfusion and minimizes ischemic transition throughout the entire process of obtaining the donor kidney from the body, perfusing it at room temperature in vitro, and transplanting it into the recipient in a small animal model. This provides a complete and feasible technical solution for constructing a small animal perfusion and transplantation model that closely approximates the clinical ischemia-free kidney transplantation model.

[0125] Simultaneously, the cannulation assembly is connected to the perfusion tubing in the perfusion method, and a reasonable switching strategy is adopted to gradually transition organ perfusion from systemic circulation to the extracorporeal perfusion circuit, while avoiding prolonged complete flow interruption. During the perfusion maintenance phase, perfusion pressure and flow are monitored and finely controlled in real time to conform to the physiological or quasi-physiological range of small animal organs. Depending on the experimental objective, organs are either directly harvested under perfusion conditions or further constructed into small animal transplantation models, achieving a single continuous perfusion and ischemia-free experimental procedure. By completing cannulation and reconnection while the organ is still in vivo and blood flow has not been completely interrupted, and maintaining continuous perfusion throughout the entire perfusion and harvesting process, the "secondary IRI" problem existing in current animal perfusion models is solved, avoiding multiple ischemia-reperfusion cycles, and also addressing the lack of unified procedures and standards for switching between in vivo cannulation and perfusion. By setting the cannulation components, perfusion tubing, and setting the pressure module to control the perfusion pressure, the hemodynamic state, perfusion method, and operation steps of small animal organs during in vivo perfusion closely resemble the actual process of clinical IFKT / IFOT. This provides a more reliable animal basis for related mechanism research and further narrows the significant gap between existing models and clinical IFKT / IFOT in terms of surgical procedures and hemodynamics.

[0126] Furthermore, during the grouting process, the changes in grouting resistance over time are observed. Figure 8 As shown, the horizontal axis represents perfusion time, and the vertical axis represents perfusion resistance. The 0-point of perfusion marks the time of ligation of the proximal abdominal aorta of the donor. It can be seen that as perfusion begins, the donor kidney is transferred to the second container at 5 minutes because the perfusion temperature is low (30℃-32℃), resulting in a significant increase in perfusion resistance. Then, as the perfusion process continues, the perfusion temperature stabilizes at 37℃-38℃ around 15 minutes, and the perfusion resistance gradually decreases. The flow rate remains stable during perfusion, with slight fluctuations at 155 minutes during the donor kidney transfer and vascular anastomosis phases, until the recipient circulation is opened at 203 minutes, at which point perfusion ends. The figure shows the changes in perfusion fluid temperature at different time points (such as 5 minutes and 15 minutes), which helps to understand how resistance is controlled during perfusion and how temperature changes affect perfusion stability.

[0127] Simultaneously, the urine produced by the recipient is monitored during perfusion, such as... Figure 9 As shown, the urine was clear during perfusion, indicating successful renal microcirculation reconstruction and restoration of metabolic function. Figure 10 As shown, the horizontal axis represents perfusion time, and the vertical axis represents urine output. As the perfusion time increases, the amount of urine produced gradually increases, indicating that the organ perfusion method of this application has strong stability for organ transplantation, and the recipient's renal function gradually recovers.

[0128] In addition, after kidney transplantation, the weight of the donor mouse, the weight of the recipient mouse, and key data on post-operative day 1 (POD1) (such as urine output, creatinine, and blood urea nitrogen) are monitored. Figure 11 As shown, number 1 represents key data from conventional normothermic mechanical perfusion (NMP) used in organ transplantation, and number 2 represents key data from transplantation using the organ perfusion method described in this application, combined with... Figure 12 , Figure 13 and Figure 14 It can be seen that the urine output (in mL) in the NMP group was significantly higher than that in the IFKT group, indicating that the NMP group could produce more urine. The IFKT group had a lower creatinine level (in mg / dL), indicating better kidney function, while the NMP group had a higher creatinine level, suggesting slower or limited kidney function recovery. The IFKT group had a lower BUN (urine nitrogen, in mg / dL), indicating stronger kidney metabolic capacity; in contrast, the NMP group had a higher BUN, indicating that kidney function recovery was not as good as that of the IFKT group. Therefore, the IFKT group is superior to the NMP group in terms of both creatinine and BUN. Compared to the typical small animal NMP experimental procedure, the kidneys in this embodiment, under the implementation of an uninterrupted blood flow small animal organ perfusion device and method, showed a significant decrease in BUN (serum urea nitrogen) and creatinine on the first postoperative day, suggesting a better postoperative kidney function protection effect. The IFKT group used the organ perfusion method of this application.

[0129] Meanwhile, this application also establishes an ischemia-free treatment process for small animal models. The core of this process is to complete the kidney acquisition, in vitro perfusion, and implantation into the recipient without stopping perfusion, and to achieve a smooth switch of blood flow from the perfusion device to the recipient's circulation, forming the following closed-loop pathway: (1) Donor in situ stage: A circuit is established in the donor body to connect the abdominal aorta / inferior vena cava cannula with the perfusion device, and the perfusion device gradually takes over the perfusion of the donor kidney; (2) Organ storage stage: Under the condition of continuous opening of the tubing and continuous flow, the donor kidney carrying the intubation tube is removed as a whole and transferred to the organ storage.

[0130] (3) Recipient implantation stage: The donor kidney is transferred to the recipient kidney bed while still in the perfusion state, vascular anastomosis is completed, and smooth blood flow is transferred from the perfusion device to the recipient's systemic circulation. Then the perfusion circuit is unloaded.

[0131] The organ perfusion device of this application connects the cannulation assembly to the arterial and venous ends of the isolated organ, respectively, and connects the cannulation assembly to the first and second containers through a first, second, and third flow path, thus constructing a closed perfusion loop. This allows for gradual perfusion of the organ without significant ischemia, achieving uninterrupted blood flow perfusion during organ acquisition, transfer, and implantation, thus creating an IFKT animal model that more closely resembles clinical practice. Simultaneously, the cannulation assembly sequentially incorporates a blunt structure specifically designed for 15G cannulation of the rat abdominal aorta, the cannulation body, a flexible connecting section, and an extension tube. This design combines flexibility and pressure resistance, facilitating placement and operation within the confined surgical area of ​​the animal, ensuring unobstructed flow during long-term perfusion. Through the design of the cannulation body and extension tube, the donor kidney can be smoothly transferred between the donor's in-situ location, the organ compartment, and the recipient's peritoneal cavity under continuous perfusion, achieving true "uninterrupted flow" at the small animal level.

[0132] Meanwhile, the perfusion device employs a multi-stage closed-loop control method that combines "setting a perfusion reference pressure + gradual pressure increase + steady-state maintenance + perfusion resistance monitoring and protection." The perfusion reference pressure is calculated and set based on the measured pressure in the donor's abdominal aorta, making the perfusion conditions closer to the original physiological state. Furthermore, the perfusion device and the multi-stage closed-loop control method are coupled with a set of engineered ischemia-free surgical procedures, from establishing the perfusion circuit in vivo on the donor side to in vitro room-temperature NMP, and then to the blood flow connection on the recipient side, forming a repeatable and standardized small animal ischemia-free transplantation technology platform.

[0133] In the description of this specification, the use of terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," and "some examples" indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0134] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. An organ perfusion device, characterized in that, include: The first container is used to store the infusion fluid; The second container is used to store excised organs; An oxygenation module is used to provide oxygen to the perfusion fluid; The perfusion tubing includes a first flow path, a second flow path, a third flow path, and a cannulation assembly. One end of the first flow path is connected to the first container, and the other end is connected to the arterial end of the isolated organ through the cannulation assembly. One end of the second flow path is connected to the venous end of the isolated organ through the cannulation assembly, and the other end is connected to the second container. The third flow path is used to connect the first container and the second container to form a circulation loop. A heating module is used to heat the infusion fluid and monitor the temperature of the infusion fluid; A pressure module, located in the first flow path, is used to monitor the infusion pressure of the infusion fluid; The main control module, which is connected to the pressure module, is used to collect pressure and other parameters during the infusion process, evaluate the infusion status based on the collected parameters, and adjust the infusion process in a timely manner.

2. The organ perfusion device according to claim 1, characterized in that, The cannulation assembly includes a cannulation body and an extension tube connected in sequence. One end of the cannulation body is provided with a blunt structure for connection with the excised organ, and the other end is connected to one end of the extension tube. The other end of the extension tube is detachably connected to the first flow path or the second flow path.

3. The organ perfusion device according to claim 2, characterized in that, The cannulation assembly also includes a flexible connecting section, one end of which is connected to the cannulation body and the other end of which is connected to the extension tube. The length of the flexible connecting section is 5mm to 10mm.

4. An organ perfusion device according to claim 3, characterized in that, The connection between the cannula body and the flexible connecting section is provided with a protruding structure, which is used to ensure the sealing of the cannula body.

5. An organ perfusion device according to claim 1, characterized in that, The heating module includes a heating element and several temperature sensors. The heating element is located in the first flow path and is used to heat the filling fluid. At least three temperature sensors are provided and are used to monitor the temperature of the filling fluid in the first flow path, the first container, and the second container.

6. An organ perfusion device according to claim 1, characterized in that, The pressure module includes an adjustable speed pump body and a pressure sensor. The first container is connected to the first flow path through the adjustable speed pump body. The adjustable speed pump body is used to provide infusion power. The pressure sensor is located on the first flow path and is used to monitor the pressure of the infusion pipeline.

7. An organ perfusion device according to claim 1, characterized in that, The organ perfusion device also includes an exhaust assembly located in the first flow path to prevent air bubbles from entering the vascular system of the isolated organ.

8. An organ perfusion device according to claim 1, characterized in that, The second container includes a shell and a fluid structure and a filter structure disposed inside the shell. The fluid structure is used to guide the perfusion fluid to flow uniformly within the shell. The filter structure is located above the fluid structure and is used to place the excised organ and to filter tissue fragments or impurities generated during the perfusion process to prevent backflow into the circulation loop.

9. An organ perfusion device according to claim 8, characterized in that, The filter structure is detachably connected to the housing, and the filter structure is provided with filter holes with a diameter of 50μm to 500μm.

10. An organ perfusion device according to claim 1, characterized in that, The main control module includes a control unit, and a data acquisition module, an early warning module, and a display module connected to the control unit. The data acquisition module is used to acquire parameters during the perfusion process, the display module is used to display the parameters, the early warning module is used to generate an early warning signal and send it to the control unit when the parameters meet preset abnormal conditions, and the control unit is used to receive the early warning signal and adjust the working status of the organ perfusion device accordingly based on the early warning signal.

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