Internal arteriovenous fistula hemodynamic research extracorporeal circulation simulation device

Abstract

The utility model relates to an internal arteriovenous fistula hemodynamics research extracorporeal circulation simulation device, the structure of which comprises an autologous arteriovenous fistula model, a liquid pump and a data acquisition device, the internal channel of the autologous arteriovenous fistula model is a Y-shaped structure, the autologous arteriovenous fistula model is provided with a first port, a second port and a third port, a liquid outlet of the liquid pump is connected with a first pipeline and a second pipeline through a first tee joint, a liquid inlet of the liquid pump is connected with a third pipeline and a fourth pipeline through a second tee joint, the second pipeline and the third pipeline are connected through a third tee joint and connected with a fifth pipeline, the first pipeline is communicated with the first port, and the third pipeline is communicated with the second port. The fifth pipeline is communicated with the third port, and a sixth pipeline is connected to the fifth pipeline in parallel; the data acquisition device comprises a flow acquisition device and an image acquisition device. According to the utility model, internal arteriovenous fistula hemodynamic data can be known conveniently, so that the influence of hemodynamics on AVF can be researched.

Description

Technical Field

[0001] The utility model relates to a hemodynamics simulation device, in particular to an extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistulas. Background Art

[0002] Currently, there are more than 2 million patients with end-stage renal disease (ESRD) in the world who need renal replacement therapy, and it is expected that by 2030, the number of ESRD patients will exceed 5 million. For ESRD patients, the kidneys have lost the ability to excrete excess water and waste, so relevant treatment methods are needed to replace the kidneys. Most ESRD patients (60%-70%) use hemodialysis for treatment. Hemodialysis is a treatment process that removes blood from the body by creating a vascular access, filters it with an external dialysis machine, and then returns the blood to the body. Therefore, vascular access is the key to the continuation of patients' lives. Compared with other methods, autologous arteriovenous fistula (AVF) has advantages such as high patency, few complications and low cost, so it is the preferred vascular access for ESRD patients. Although autologous arteriovenous fistula provides a lifeline for patients, due to many adverse factors, the fistula vascular system also has a non-negligible failure rate before and after its maturity.

[0003] The failure of dialysis vascular access is mainly caused by two different mechanisms. One is that it occurs in the early stage, and the outward remodeling of the blood vessels is insufficient or impaired, that is, the blood flow cannot meet the requirements due to insufficient expansion of the blood vessel diameter or thickening of the wall; the other is caused by stenosis. Stenosis is the narrowing of the blood vessels in the anastomotic area of ​​AV fistula (JXA), which is the most common factor threatening the patency of AV fistula. It is usually caused by intimal hyperplasia (IH). It is known that hemodynamics that cause endothelial cell damage in the vascular wall are an important factor in causing IH. In order to explore the detailed pathogenesis of AVF failure, multidisciplinary studies have been conducted. Magnetic resonance angiography and spiral computed tomography have been used to demonstrate their clinical feasibility for evaluating AVF. However, they only provide morphological data and 3D vascular visualization. In addition, most of the research in this field aims to develop computational models to study how parameters such as vascular and graft geometry affect wall shear stress. This method will not be used by doctors unless they have been verified by "real pathological cases." Clinicians still need an early, potentially noninvasive tool to quantify the hemodynamic effects of AVFs, but there is no device in the current technology that can record relevant data for studying the hemodynamic effects of AVFs. Utility Model Content

[0004] The purpose of the utility model is to provide an extracorporeal circulation simulation device for studying the hemodynamics of an arteriovenous fistula, so as to solve the problem that there is no device in the prior art that can record relevant data for studying the influence of hemodynamics on AVF.

[0005] The utility model is implemented as follows: an extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistula, comprising an autologous arteriovenous fistula model, a liquid pump and a data acquisition device, wherein the internal channel of the autologous arteriovenous fistula model is a Y-shaped structure, the autologous arteriovenous fistula model has a first port, a second port and a third port, the liquid outlet of the liquid pump is connected with a first pipeline and a second pipeline through a first tee, the liquid inlet of the liquid pump is connected with a third pipeline and a fourth pipeline through a second tee, the second pipeline is connected with the third pipeline through a third tee and is connected with a fifth pipeline, the first pipeline is communicated with the first port, the third pipeline is communicated with the second port, the fifth pipeline is communicated with the third port, a sixth pipeline is connected in parallel to the fifth pipeline, and valves are respectively arranged on the first pipeline, the second pipeline, the third pipeline, the fourth pipeline, the fifth pipeline and the sixth pipeline; the data acquisition device comprises a flow acquisition device for acquiring hemodynamic flow velocity and flow information of the autologous arteriovenous fistula model and an image acquisition device for acquiring hemodynamic image information of the autologous arteriovenous fistula model.

[0006] As a further improvement of the extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistulas of the utility model, the image acquisition device includes a laser and an image shooting device arranged beside the autologous arteriovenous fistula model, and the autologous arteriovenous fistula model is made of a transparent material.

[0007] As a further improvement of the extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistulas of the utility model, the image shooting device is a CCD camera.

[0008] As a further improvement of the extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistulas of the utility model, the flow acquisition device flow meter is respectively provided with a flow meter on the first pipeline, the third pipeline, the fifth pipeline and the sixth pipeline.

[0009] As a further improvement of the extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistulas of the utility model, the flow meter is an ultrasonic flow meter.

[0010] As a further improvement of the utility model of the extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistula, the liquid pump is a pulse pump.

[0011] As a further improvement of the extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistulas of the utility model, the autologous arteriovenous fistula model structure is designed according to the clinical imaging data of real patients and is manufactured at a 1:1 ratio.

[0012] As a further improvement of the extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistula of the utility model, the autologous arteriovenous fistula model is an end-to-side connection model of the cephalic vein and the radial artery.

[0013] The utility model drives liquid to circulate in an extracorporeal circulation simulation device for studying the hemodynamics of an arteriovenous fistula by a liquid pump. The liquid passes through an autologous arteriovenous fistula model to simulate the fluid flow field when blood passes through the autologous arteriovenous fistula. Through the coordination of valves and various pipelines, the conversion between the shunt mode and the reflux mode, as well as the fluid flow field conditions under different flow ratios of each pipeline and each conduit can be achieved, which is convenient for understanding the hemodynamic data of the arteriovenous fistula and subsequent analysis and research, and can help relevant scientific researchers determine the impact of relevant hemodynamics on AVF. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural diagram of the utility model.

[0015] In the figure: 1. autologous arteriovenous fistula model; 2. pulse pump; 3. first three-way; 4. first pipeline; 5. second pipeline; 6. second three-way; 7. third pipeline; 8. fourth pipeline; 9. third three-way; 10. fifth pipeline; 11. sixth pipeline; 12. first ultrasonic flowmeter; 13. second ultrasonic flowmeter; 14. third ultrasonic flowmeter; 15. fourth ultrasonic flowmeter; 16. first valve; 17. second valve; 18. third valve; 19. fourth valve; 20. fifth valve; 21. sixth valve; 22. laser; 23. first CCD camera; 24. second CCD camera; 25. synchronous controller; 26. image processing device; 27. host computer; 1-1. first port; 1-2. second port; 1-3. third port; 2-1. liquid inlet; 2-2. liquid outlet. DETAILED DESCRIPTION

[0016] The utility model is further described below in conjunction with the accompanying drawings.

[0017] like Figure 1 As shown, the utility model is an extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistula, comprising an autologous arteriovenous fistula model 1, a liquid pump 2 and a data acquisition device.

[0018] Among them, the internal channel of the autologous arteriovenous fistula model 1 (AVF model) is a Y-shaped structure, and the autologous arteriovenous fistula model 1 has a first port 1-1, a second port 1-2 and a third port 1-3, and the first port 1-1, the second port 1-2 and the third port 1-3 correspond to the proximal end of the radial artery, the proximal end of the cephalic vein and the distal end of the radial artery, respectively.

[0019] The liquid pump 2 is provided with a liquid inlet 2-1 and a liquid outlet 2-2, and the liquid pump 2 is connected to the autologous arteriovenous fistula model 1 through a pipeline. Among them, the liquid outlet 2-2 of the liquid pump 2 is connected to the first pipeline 4 and the second pipeline 5 through the first tee 3, the liquid inlet 2-1 of the liquid pump 2 is connected to the third pipeline 7 and the fourth pipeline 8 through the second tee 6, and the second pipeline 5 is connected to the third pipeline 7 through the third tee 9 and is connected to the fifth pipeline 10. The first pipeline 4 is connected to the first port 1-1, the third pipeline 7 is connected to the second port 1-2, the fifth pipeline 10 is connected to the third port 1-3, and the sixth pipeline 11 is connected in parallel to the fifth pipeline 10.

[0020] The first valve 16, the second valve 17, the third valve 18, the fourth valve 19, the fifth valve 20 and the sixth valve 21 are respectively arranged on the first pipeline 4, the second pipeline 5, the third pipeline 7, the fourth pipeline 8, the fifth pipeline 10 and the sixth pipeline 11. By opening and closing each valve, the passage can be controlled to be transformed into two corresponding modes of shunt and confluence according to experimental requirements, wherein the confluence means that the fluids at the proximal end of the radial artery and the distal end of the radial artery both flow to the cephalic vein, and the shunt means that the fluids at the proximal end of the radial artery flow to the distal end of the radial artery and the cephalic vein.

[0021] The diversion mode is: open the first valve 16, the third valve 18, the fourth valve 19 and the sixth valve 21, close the second valve 17 and the fifth valve 20, the liquid flows out through the outlet 2-2 of the liquid pump 1, flows into the proximal end of the radial artery of the autologous arteriovenous fistula model 1 from the first port 1-1 through the first pipeline 4, and then flows from the proximal end of the cephalic vein of the second port 1-2 to the third pipeline 7 and then returns to the inlet 2-1 of the liquid pump, and at the same time flows from the distal end of the radial artery of the third port 1-3 to the sixth pipeline 11, and returns to the inlet 2-1 of the liquid pump 2 through the fourth pipeline 8.

[0022] The confluence mode is: open the first valve 16, the second valve 17, the fifth valve 20 and the third valve 18, close the fourth valve 19 and the sixth valve 21, the liquid flows out through the outlet 2-2 of the liquid pump 2, one branch flows into the proximal end of the radial artery of the autologous arteriovenous fistula model 1 from the first port 1-1 through the first pipeline 4, and the other branch flows into the distal end of the radial artery of the autologous arteriovenous fistula model 1 from the third port 1-3 through the second pipeline 5 and the fifth pipeline 10. The liquids of the two branches converge at the proximal end of the cephalic vein and flow out through the second port 1-2, and return to the inlet 2-1 of the liquid pump 2 through the third pipeline 7.

[0023] The data acquisition device includes a flow acquisition device for acquiring hemodynamic flow velocity and flow information of the autologous arteriovenous fistula model 1 and an image acquisition device for acquiring hemodynamic image information of the autologous arteriovenous fistula model 1 .

[0024] The autologous arteriovenous fistula model 1 (AVF model) is designed based on the clinical imaging data of real patients and is 3D printed using transparent materials. Specifically, silicone material can be used. The appearance of the silicone model is completely transparent (transparency reaches 98.9%) and the density is 1.1g / cm 3 , hardness (ShoreA): 30A, tensile strength is 4.5±0.5MPa, elongation at break: 350%, tear strength: 12±2KN / m, friction system is 1.32, with a highly vivid structure and operational feel, matching human attributes, making it convenient for relevant scientific researchers to test related hemodynamics on this model.

[0025] The autologous arteriovenous fistula model 1 (AVF model) is a Y-shaped structure formed by connecting the cephalic vein and the radial artery end to end.

[0026] The utility model uses water plus tracer particles as simulated liquid, and the tracer particles are fluorescent particles with a diameter of 1 micron to 5 microns. The liquid used in the utility model is not limited to the simulated liquid of water plus tracer particles, and a mixed liquid with similar hemodynamic properties can also be used.

[0027] The image acquisition device includes a laser 22 and an image shooting device arranged beside the autologous arteriovenous fistula model 1. The laser 22 is a 532nm pulse laser 22. The laser 22 emits laser to illuminate the tracer particles in the internal flow field of the pipeline that needs to be detected in the experiment, so that the image shooting device can shoot the flow field to obtain a clear image.

[0028] The image capture device is a CCD camera. In order to ensure the accuracy of image acquisition, a high-resolution industrial camera is selected. Generally, there are two image capture devices. The first CCD camera 23 and the second CCD camera 24 are located on the same side of the autologous arteriovenous fistula model 1 and on the opposite side of the laser 22. The first CCD camera 23 and the second CCD camera 24 are tilted at a certain angle to each other to capture images of the pipeline in the autologous arteriovenous fistula model 1 from two directions.

[0029] The flow collection device is a flow meter, specifically an ultrasonic flow meter, and a first ultrasonic flow meter 12, a second ultrasonic flow meter 13, a third ultrasonic flow meter 14 and a fourth ultrasonic flow meter 15 are respectively arranged on the first pipeline 4, the second pipeline 5, the fifth pipeline 10 and the sixth pipeline 11. The ultrasonic flow meter can monitor the flow at the first port 1-1, the second port 1-2 and the third port 1-3. The ultrasonic flow meter is an ultrasonic flow meter based on the time difference method, which can measure the liquid flow and flow rate in the liquid-filled pipeline by a non-contact method.

[0030] Liquid pump 2 is a portable pulsating pump, which can be purchased on the market. It is a fluid power providing device used to generate periodic pulsating fluid to simulate the flow state of blood in the left heart / right heart of the human body, including periodic pulsating circulation, liquid temperature control and pressure monitoring functions. The portable pulsating pump consists of an open atrium, two built-in ball valves, a voice coil motor and a compliance module. By controlling the movement of the motor, the periodic pulsating flow of the liquid can be achieved.

[0031] The valve in the utility model is an electric valve, specifically an electric spherical valve. The valve core of the electric valve can rotate 0°-90°, and can receive 0-10V voltage signal control. The 0-10V voltage signal corresponds to the 0°-90° rotation angle of the electric valve, which can realize the control of the opening and closing angle of the valve core of the electric valve, and realize the rapid conversion of the two modes of pipeline diversion and confluence.

[0032] Based on the combination of the above equipment, the utility model has built an extracorporeal AVF circulation device, which can well reproduce the real AVF structure of the human body and can produce blood flow conditions similar to those of the human body. Through the designed pipeline pathway combined with the control of the electric valve, researchers can achieve rapid conversion between diversion and confluence without disassembling the pipeline. By installing an ultrasonic flowmeter on the pipeline, the flow rate and flow velocity in the AVF-related pipeline can be well measured. And the AVF model used is a fully transparent silicone model, which is convenient for obtaining the flow field image inside the model. The utility model can help relevant researchers determine the impact of relevant hemodynamics on AVF, and thus provide guidance for clinical practice.

[0033] Further, in one embodiment of the utility model, the utility model also includes a synchronous controller 25 and a host computer 27 system, the host computer 27 system is connected to each valve and the ultrasonic flow meter, the flow rate data monitored is stored by the host computer 27 system, the PC of the image processing device 26 is connected to the synchronous controller 25, the synchronous controller 25 is connected to the laser 22, the PC in the image processing device 26 is equipped with an image acquisition card and is connected to the first CCD camera 23 and the second CCD camera 24, forming a PIV (particle image velocimetry) system. After power-on is completed, the PC in the image processing device 26 issues an image acquisition instruction, and the synchronous controller 25 sends a trigger signal to the image acquisition card connected to the laser 22 and the PC according to the set information timing relationship after receiving the instruction. When the laser 22 and the image acquisition card receive the trigger signal, the on-site image is recorded according to the principle of cross-frame image acquisition. Finally, by processing the recorded image data and flow data, the influence of related hemodynamics on AVF can be explored, providing a theoretical basis for clinicians to improve the success rate of AVF.

[0034] It should be noted that the ultrasonic flow meter, electric valve, portable pulsating pump and CCD camera, laser 22, synchronous controller 25 and image processing device 26 used in the utility model are all conventional equipment in the prior art. Their use and installation methods are detailed in the operating instructions of each device. They are well known in the prior art and will not be elaborated in the utility model.

Claims

1. An extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistula, characterized in that: The invention comprises an autologous arteriovenous fistula model, a liquid pump and a data acquisition device, wherein the internal channel of the autologous arteriovenous fistula model is a Y-shaped structure, the autologous arteriovenous fistula model has a first port, a second port and a third port, the liquid outlet of the liquid pump is connected to the first pipeline and the second pipeline through a first tee, the liquid inlet of the liquid pump is connected to the third pipeline and the fourth pipeline through a second tee, the second pipeline and the third pipeline are connected through a third tee and are connected to a fifth pipeline, the first pipeline is communicated with the first port, the third pipeline is communicated with the second port, the fifth pipeline is communicated with the third port, a sixth pipeline is connected in parallel to the fifth pipeline, and valves are respectively arranged on the first pipeline, the second pipeline, the third pipeline, the fourth pipeline, the fifth pipeline and the sixth pipeline; the data acquisition device comprises a flow acquisition device for acquiring hemodynamic flow velocity and flow information of the autologous arteriovenous fistula model and an image acquisition device for acquiring hemodynamic image information of the autologous arteriovenous fistula model.

2. The device for simulating extracorporeal circulation for studying the hemodynamics of arteriovenous fistula according to claim 1, characterized in that: The image acquisition device comprises a laser and an image shooting device which are arranged beside the autologous arteriovenous fistula model, and the autologous arteriovenous fistula model is made of a transparent material.

3. The extracorporeal circulation simulation device for studying arteriovenous fistula hemodynamics according to claim 2, characterized in that: The image capturing device is a CCD camera.

4. The extracorporeal circulation simulation device for studying arteriovenous fistula hemodynamics according to claim 1, characterized in that: The flow collection device flow meter is provided on the first pipeline, the third pipeline, the fifth pipeline and the sixth pipeline respectively.

5. The device for simulating extracorporeal circulation for studying the hemodynamics of arteriovenous fistula according to claim 4, characterized in that: The flow meter is an ultrasonic flow meter.

6. The device for simulating extracorporeal circulation for studying the hemodynamics of arteriovenous fistula according to claim 1, characterized in that: The liquid pump is a pulse pump.

7. The device for simulating extracorporeal circulation for studying the hemodynamics of arteriovenous fistula according to claim 1, characterized in that: The autologous arteriovenous fistula model structure is designed based on clinical imaging data of real patients and is manufactured in a 1:1 ratio.

8. The extracorporeal circulation simulation device for studying the hemodynamics of arteriovenous fistula according to claim 1, characterized in that: The autologous arteriovenous fistula model is an end-to-side connection model of the cephalic vein and the radial artery.

Images