Dialysis catheter with thrombosis prevention

Abstract

The application discloses a dialysis catheter for preventing thrombosis, which comprises a catheter main body, a first flow channel, a second flow channel and a third flow channel being arranged along the axial direction of the catheter main body, and being used for blood extraction and blood return during dialysis respectively; a one-way valve and a blocking balloon being connected to the input end and the output end of the third flow channel of the catheter main body respectively, and the third flow channel being used for conveying an anti-thrombotic drug; wherein the surface of the blocking balloon and / or the surface of the catheter main body is provided with a microporous structure communicated with the third flow channel, and when the anti-thrombotic drug is gradually flowed into the blocking balloon through the one-way valve and the third flow channel, the blocking balloon is changed to an inflated state, so that the inflated blocking balloon causes the first flow channel and the second flow channel to be closed, and the sidewall of the blocking balloon and / or the catheter main body gradually releases the anti-thrombotic drug in the body. The application solves the technical problem that it is difficult to effectively prevent thrombosis when the dialysis catheter is used for dialysis and is left for a long time.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a dialysis catheter that prevents thrombosis. Background Technology

[0002] Vascular access is the lifeline for hemodialysis patients. A stable and reliable vascular access is the fundamental guarantee for maintenance hemodialysis patients. With an aging population, the increasing dialysis duration of maintenance hemodialysis patients, and the rising incidence of hypertension, diabetes, obesity, and autoimmune diseases, establishing autologous fistulas is becoming increasingly difficult. Long-term dialysis catheters have become an inevitable choice to ensure adequate dialysis for patients. Statistics show that in clinical use, 40% of catheter failures are attributed to venous thrombosis and fibrin sheath formation, and approximately 17%-33% of forced catheter removals are due to thrombosis. Complications of thrombosis lead to insufficient flow rate, prolonged dialysis time, and increased costs, severely impacting patients' quality of life.

[0003] In the prior art, to prevent thrombosis, a venous catheter with a balloon is usually used, which includes a double-lumen venous catheter and a balloon catheter. Specifically, it includes a first lumen and a second lumen, and the balloon catheter is located between the first lumen and the second lumen. The balloon catheter includes a branch, a piston and a balloon. The piston is installed at one end of the branch, and the balloon is fitted at the other end of the branch. The function of the balloon is to close the first lumen and the second lumen by inflating, which can prevent thrombosis in the catheter.

[0004] However, while blocking the first and second lumens used to deliver blood with an inflatable balloon can prevent thrombosis to some extent, it can only prevent thrombosis from forming inside the tube and increase the blood flow rate within the tube. However, thrombosis is multi-directional and multi-faceted. As the catheter remains in place for longer periods, many factors can affect the catheter's outer wall, especially the tip, leading to catheter thrombosis. This thrombus adheres to the catheter surface, resulting in insufficient blood flow in the vein and threatening the patient's life. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a dialysis catheter that prevents thrombosis, thereby solving the technical problem that long-term indwelling dialysis catheters in the prior art can easily lead to thrombosis.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution: A dialysis catheter for preventing thrombosis, the dialysis catheter comprising: The catheter body has a first flow channel, a second flow channel and a third flow channel running through it along its axis. The first flow channel and the second flow channel are used for blood drawing and blood return during dialysis, respectively. A one-way valve and an occlusion balloon are respectively connected to the input and output ends of the third flow channel in the catheter body, the third flow channel being used to deliver antithrombotic drugs; The occlusion balloon and / or the catheter body have a perforated microporous structure communicating with the third flow channel. When the antithrombotic drug is injected through the one-way valve and gradually flows into the occlusion balloon through the third flow channel, the occlusion balloon changes to an inflated state, so that the inflated occlusion balloon seals the first flow channel and the second flow channel. The microporous structure on the surface of the occlusion balloon and / or the catheter body gradually releases the antithrombotic drug.

[0007] According to one aspect of the above technical solution, the first flow channel, the second flow channel, and the third flow channel are all recessed within the catheter body to form a receiving space within the catheter body for accommodating the occlusion balloon. The occlusion balloon is connected to the third flow channel to restrict the axial degree of freedom of the occlusion balloon.

[0008] According to one aspect of the above technical solution, a positioning component is provided between the occlusion balloon and the inner wall of the catheter body, including a first positioning member and a second positioning member. The first positioning member and the second positioning member cooperate with each other to position the occlusion balloon, thereby restricting the radial degree of freedom of the occlusion balloon.

[0009] According to one aspect of the above technical solution, the first positioning member is protruding and disposed on the outer side of the occlusion balloon, and the second positioning member is recessed and disposed on the inner side wall of the catheter body, with the first positioning member being inserted into the second positioning member.

[0010] According to one aspect of the above technical solution, the outer side of the occlusion balloon is provided with two first positioning elements, and the inner sidewall of the catheter body is provided with two second positioning elements corresponding to the first positioning elements respectively.

[0011] According to one aspect of the above technical solution, the third flow channel is located between the first flow channel and the second flow channel, and the inflation of the occlusion balloon will seal the first flow channel and the second flow channel located on both sides.

[0012] According to one aspect of the above technical solution, the catheter body is provided with a first notch communicating with the first flow channel and a second notch communicating with the second flow channel on the outside of the occlusion balloon.

[0013] According to one aspect of the above technical solution, the one-way valve includes a valve body, a valve core disposed within the valve body, and an elastic element for supporting the valve core. The valve body is connected to the third flow channel through a through-flow valve body channel. The elastic element and the valve core are positioned in a supporting position within the valve body flow channel to unidirectionally close the valve body flow channel.

[0014] According to one aspect of the above technical solution, an elastic balloon is also connected in series between the one-way valve and the conduit body, and the one-way valve is connected to the third flow channel through the elastic balloon and the balloon conduit.

[0015] According to one aspect of the above technical solution, the occlusion balloon is flat in its initial state.

[0016] Compared with existing technologies, the advantages of using the anti-thrombotic dialysis catheter shown in this invention are as follows: By forming a first, second, and third flow channel inside the catheter body, and by installing one-way valves at both ends of the third flow channel on the catheter body for the one-way passage of antithrombotic drugs, as well as occlusion balloons for storing and releasing antithrombotic drugs, when dialysis treatment is not being performed and the dialysis catheter is left in the body, antithrombotic drugs are injected into the one-way valves. The antithrombotic drugs will enter the occlusion balloon along the third flow channel. The occlusion balloon gradually inflates, and the inflated occlusion balloon will block the first and second flow channels, isolating the first and second flow channels from the patient's blood vessels. Blood will no longer enter the first and second flow channels, preventing thrombus formation inside the catheter. At the same time, the antithrombotic drugs are slowly released through the microporous structure on the surface of the occlusion balloon and / or the microporous structure on the surface of the catheter body that connects to the third flow channel. This can eliminate thrombi formed at the catheter tip due to the anchoring effect caused by the dead point at the dialysis catheter tip, as well as thrombi formed on the catheter surface. Therefore, the dialysis catheter shown in this invention can effectively prevent thrombosis compared to traditional long-term dialysis catheters. It is consistent in terms of catheter placement, use, and maintenance, requires no other consumables, and will not increase the economic burden on patients. Attached Figure Description

[0017] The above and / or additional aspects and advantages of the present invention 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 three-dimensional structural schematic diagram of the dialysis catheter shown in an embodiment of the present invention; Figure 2 This is an exploded view of a portion of the dialysis catheter structure shown in an embodiment of the present invention; Figure 3 This is a schematic diagram of the dialysis catheter in a first horizontal state according to an embodiment of the present invention; Figure 4 for Figure 3 Sectional view along the middle AA direction; Figure 5 for Figure 4 Enlarged diagram of section A in the middle; Figure 6 for Figure 4 Enlarged schematic diagram of section B in the middle; Figure 7 This is a schematic diagram of the dialysis catheter in the second horizontal state according to an embodiment of the present invention; Figure 8 for Figure 7 Sectional view along the BB direction; Figure 9 for Figure 8 Enlarged diagram of section C; Figure 10 for Figure 8 Enlarged schematic diagram of section D in the middle; Component symbol explanation in the attached diagram: The conduit body 10, first flow channel 11, second flow channel 12, third flow channel 13, accommodating space 14, second positioning element 141, first notch 142, second notch 143, one-way valve 20, valve body 21, valve core 22, elastic element 23, sealing balloon 30, first positioning element 301, balloon fixing tube 302, elastic balloon 40, balloon conduit 41, connector 50, extension tube 51, and conduit seat 52. Detailed Implementation

[0018] To make the objectives, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Several embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the present invention will be more thorough and complete.

[0019] It should be noted that when a component is said to be "fixed to" another component, it can be directly on the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] In clinical practice, after a patient completes dialysis treatment, an antithrombotic drug (heparinized saline or other anticoagulants) is injected into the lumen of the dialysis catheter through the catheter port to empty and seal the lumen. However, because the catheter tip is open, blood slowly seeps into the lumen during catheter placement. Since the fluid inside the lumen is relatively stagnant, the blood entering the lumen slowly coagulates and adheres to the catheter wall. As the catheter placement time increases, a thrombus eventually forms, blocking the catheter lumen, resulting in insufficient flow and affecting the patient's treatment. The purpose of this invention is to provide a dialysis catheter that can prevent thrombus formation, thus meeting the requirements for long-term indwelling dialysis catheter use.

[0022] Example 1 Please see Figures 1-10 The first embodiment of the present invention provides a dialysis catheter that prevents thrombosis and can be used for both short-term and long-term placement. The dialysis catheter shown in this embodiment is mainly used for long-term placement in hemodialysis and can prevent thrombosis during long-term placement, that is, prevent the formation of thrombi in blood vessels to affect the normal flow of blood.

[0023] The dialysis catheter shown in this embodiment includes a catheter body 10, a one-way valve 20, and an occlusion balloon 30.

[0024] The catheter body 10 has a first flow channel 11 and a second flow channel 12 extending through it along its axial direction. The first flow channel 11 and the second flow channel 12 are respectively inserted through the catheter body 10 and are both arranged along the axial direction of the catheter body 10. For example, the first flow channel 11 is used for blood transfusion during hemodialysis, that is, blood from the patient's blood vessels is output to the hemodialysis machine for purification. The second flow channel 12 is used for blood return during hemodialysis, that is, the purified blood from the hemodialysis machine is returned to the patient's blood vessels, thus achieving hemodialysis through a continuous cycle.

[0025] The catheter body 10 also includes a third flow channel 13 extending axially within it. This third flow channel 13 is formed between the first flow channel 11 and the second flow channel 12. The first, second, and third flow channels 11 and 12 are parallel and independent of each other, meaning they are spaced apart. This third flow channel 13 is used for anti-thrombotic measures during catheter placement after hemodialysis. It delivers anti-thrombotic drugs into the patient's blood vessels to prevent thrombosis when hemodialysis is not being performed. Furthermore, since the newly designed third flow channel 13 occupies space within the first and second flow channels 11 and 12, the cross-sections of the first and second flow channels 11 and 12 are larger than the cross-section of the third flow channel 13. By having larger cross-sections for the first and second flow channels 11 and 12, the normal use of the dialysis catheter can be ensured, while also allowing the third flow channel 13 to function as a sustained-release channel.

[0026] It should be noted that although dialysis catheters have three flow channels inside, their diameter is actually quite small, typically between 6mm and 7mm, suitable for most adult patients. Of course, the diameter of the dialysis catheter can be increased or decreased accordingly to accommodate a wider range of patients.

[0027] In this embodiment, the dialysis catheter is also provided with a one-way valve 20 and a occlusion balloon 30 for communicating with the third flow channel 13. The one-way valve 20 and the occlusion balloon 30 are respectively located at the input end and the output end of the third flow channel 13 on the catheter body 10.

[0028] The one-way valve 20 allows antithrombotic drugs to pass through in one direction into the third channel 13, while the occlusion balloon 30 expands when the antithrombotic drugs accumulate, thereby sealing the first channel 11 and the second channel 12 respectively. This prevents blood from flowing back into the first channel 11 and / or the second channel 12 and solidifying to form a thrombus. The occlusion balloon 30 can continuously release antithrombotic drugs into the patient's blood, eliminating thrombi formed due to the anchoring effect caused by the dead angle at the tip of the dialysis catheter.

[0029] Specifically, the one-way valve 20 and the occlusion balloon 30 are respectively connected to the two ends of the third flow channel 13 in the catheter body 10, that is, connected to the input end and the output end of the third flow channel 13. The one-way valve 20 includes a valve body 21, which has a valve body flow channel running through it. The valve core 22 and the elastic element 23 for supporting the valve core 22 are disposed in the valve body flow channel. Under the action of the elastic element 23, the valve core 22 abuts against the end face of the valve body 21 in the valve body flow channel, thereby enabling the one-way valve 20 to have a one-way shut-off function. When an antithrombotic drug is injected through the one-way valve 20, the antithrombotic drug can overcome the elastic force applied by the elastic element 23, causing the elastic element 23 to be at least partially compressed. The valve core 22 moves synchronously into the valve body flow channel, and the end face of the valve core 22 separates from the valve body 21. Then the antithrombotic drug can enter the valve body flow channel from the valve core 22, and thus enter the third flow channel 13.

[0030] When the antithrombotic drug enters through the one-way valve 20 and the third channel 13, the antithrombotic drug gradually accumulates in the occlusion balloon 30, causing the occlusion balloon 30 to expand. The expanded occlusion balloon 30 will seal the first channel 11 and the second channel 12 in the catheter body 10, thereby forming a gap between the patient's blood vessels and the first channel 11 and the second channel 12. When the dialysis catheter is left in the body, the blood in the patient's blood vessels will not enter the first channel 11 and the second channel 12, which can prevent blood from flowing back into the first channel 11 and the second channel 12 and solidifying to form a thrombus.

[0031] In addition, the surface of the occlusion balloon 30 has a large number of microporous structures. When the antithrombotic drug accumulates and causes the occlusion balloon 30 to expand, the microporous structures on its surface will become larger accordingly. The change in the microporous structure will enable the antithrombotic drug to have better flowability. When the occlusion balloon 30 expands, the antithrombotic drug can be gradually released through the occlusion balloon 30 at the tip of the catheter body 10, thereby eliminating the anchor point effect caused by the dead corner of the dialysis catheter tip and the thrombus formed.

[0032] In this embodiment, it should also be noted that, since the diameter of the catheter body 10 is small and the occlusion balloon 30 is located inside the catheter body 10 and connected to the end of the third flow channel 13, the diameter of the occlusion balloon 30 is correspondingly smaller. Although the occlusion balloon 30 needs to expand to block the first flow channel 11 and the second flow channel 12 and release antithrombotic drugs, due to the limitation of the dialysis catheter diameter, the expansion degree of the occlusion balloon 30 is actually small and not obvious. It is only necessary to ensure that the expanded occlusion balloon 30 can block the first flow channel 11 and the second flow channel 12 respectively.

[0033] More specifically, the first flow channel 11, the second flow channel 12, and the third flow channel 13 are all recessed within the catheter body 10, thereby forming a receiving space 14 at the end of the catheter body 10 for accommodating the occlusion balloon 30. The occlusion balloon 30 is disposed within the receiving space 14, and the side of the occlusion balloon 30 near the third flow channel 13 is connected to the third flow channel 13 through a through-hole balloon fixation tube 302. The balloon fixation tube 302 and the third flow channel 13 are connected by heat fusion, thereby effectively restricting the axial degree of freedom of the occlusion balloon 30 and preventing the occlusion balloon 30 from moving out. Moreover, the balloon fixation tube 302 is a hollow structure, so the antithrombotic drug in the third flow channel 13 can enter the occlusion balloon 30 through the balloon fixation tube 302. The occlusion balloon 30 expands within the receiving space 14 to block the first flow channel 11 and the second flow channel 12 recessed within the catheter body 10.

[0034] Furthermore, in order to further improve the stability of the occlusion balloon 30 within the accommodating space 14 of the catheter body 10, a positioning component for positioning the occlusion balloon 30 is provided between the occlusion balloon 30 and the catheter body 10. The positioning component includes a first positioning member 301 and a second positioning member 141. The first positioning member 301 and the second positioning member 141 cooperate with each other to further fix the occlusion balloon 30. Specifically, it is used to limit the radial degree of freedom of the occlusion balloon 30 within the accommodating space 14, that is, to prevent the occlusion balloon 30 from rotating within the accommodating space 14 of the catheter body 10.

[0035] The terms "first" and "second" in "first positioning element 301" and "second positioning element 141" are used only to distinguish the two positioning elements and have no other specific referential meaning.

[0036] In this embodiment, the first positioning member 301 is located on the outer side of the occlusion balloon 30 and is protruding. There are two first positioning members 301, which are respectively located on two mutually distant sides of the occlusion balloon 30. The second positioning member 141 is located on the inner wall of the catheter body 10 and is recessed. There are also two second positioning members 141, which are respectively located on two mutually distant sides of the inner wall of the catheter body 10. The first positioning member 301 on the outer side of the occlusion balloon 30 is inserted into the second positioning member 141 of the catheter body 10, thereby further fixing the occlusion balloon 30 and restricting the radial freedom of the occlusion balloon 30 within the accommodating space 14 of the catheter body 10, thus preventing the occlusion balloon 30 from rotating.

[0037] Furthermore, the two first positioning elements 301 can also be connected as one unit to form the basic framework of the occlusion balloon 30.

[0038] It should also be noted that, since positioning components are provided on both sides of the occlusion balloon 30, it will inevitably have a certain impact on the expansion and change of the occlusion balloon 30. Taking the first positioning element 301 and the second positioning element 141 located on the lateral sides of the occlusion balloon 30 as an example, since the first positioning element 301 and the second positioning element 141 are located on the lateral sides of the occlusion balloon 30, the presence of the first positioning element 301 and the second positioning element 141 will cause a certain obstruction to the lateral expansion of the occlusion balloon 30. Therefore, the occlusion balloon 30 can only be fully expanded on the vertical sides. The vertically expanded occlusion balloon 30 is similar to the number "8". The vertical sides of the occlusion balloon 30 need to be directly aligned with the first flow channel 11 and the second flow channel 12 in the catheter body 10, so that the first flow channel 11 and the second flow channel 12 can be blocked by the expanded occlusion balloon 30.

[0039] In this embodiment, to improve the permeability of blood and antithrombotic drugs at the end of the catheter body 10, a first notch 142 communicating with the first flow channel 11 and a second notch 143 communicating with the second flow channel 12 are formed on the outer side of the occlusion balloon 30 on the catheter body 10. When using this dialysis catheter for dialysis, because the occlusion balloon 30 is flattened, blood in the patient's blood vessels can enter the first flow channel 11 through the first notch 142, while blood in the second flow channel 12 can flow into the patient's blood vessels through the second notch 143. The presence of this notch increases the permeability of dialysis drugs. Even when hemodialysis is not being performed but the dialysis catheter remains in the patient's body, the antithrombotic drugs in the inflated occlusion balloon 30 can flow out not only through the end of the catheter body 10 but also through the notch, thus improving the permeability of antithrombotic drugs.

[0040] In some feasible embodiments, the antithrombotic drug is heparinized saline (or other anticoagulant), which slowly permeates outward through the micropores on the surface of the balloon 30 to produce a drug-like sustained-release effect, thereby eliminating thrombi formed due to the anchoring effect caused by the dead point at the tip of the dialysis catheter.

[0041] In this embodiment, the dialysis catheter also includes two extension tubes 51. The two extension tubes 51 are connected to the first flow channel 11 and the second flow channel 12 on the catheter body 10 via connectors 50. A catheter seat 52 is also provided on the side of the extension tube 51 away from the catheter body 10. This catheter seat 52 is used to connect other accessories of the hemodialysis machine. Specifically, the connector 50 is a Y-shaped connector 50, which has two mutually isolated flow channels inside. By connecting the catheter body 10 and the extension tubes 51 on both sides of the flow channels, the two extension tubes 51 are connected to the first flow channel 11 and the second flow channel 12 respectively through the internally preset flow channels, facilitating blood delivery.

[0042] The dialysis catheter shown in this embodiment is used as follows: After the patient completes dialysis treatment, the dialysis catheter will be used for sustained drug release to prevent thrombosis. Specifically, an antithrombotic drug (heparinized saline or other anticoagulant) is injected into the one-way valve 20. The antithrombotic drug will flow into the occlusion balloon 30 along the third channel 13, causing the occlusion balloon 30 to gradually inflate. The inflated occlusion balloon 30 can completely seal the first channel 11 and the second channel 12 of the catheter body 10. Because the surface of the occlusion balloon 30 is covered with a microporous structure, the antithrombotic drug filling the occlusion balloon 30 can continuously, evenly and slowly permeate outward, thereby achieving the purpose of preventing thrombosis at the catheter tip.

[0043] It is also worth noting that when hemodialysis is not being performed, the first channel 11 and the second channel 12 can also be used to deliver antithrombotic drugs or other therapeutic drugs. The catheter body 10 has a microporous structure that connects the first channel 11 and the second channel 12. When the occlusion balloon 30 blocks the first channel 11 and the second channel 12, the antithrombotic drug is injected into the first channel 11 and the second channel 12. The antithrombotic drug will be released through the microporous structure that connects the first channel 11 and the second channel 12, which can enhance the antithrombotic effect when the dialysis catheter is in place.

[0044] Before the next dialysis session, the injection of antithrombotic drugs into the one-way valve 20 is stopped. Using a syringe or other device, the antithrombotic drugs in the third flow channel 13 and the occlusion balloon 30 are aspirated, restoring the occlusion balloon 30 to its initial flattened state and re-exposing the first flow channel 11 and the second flow channel 12 at the tip of the catheter body 10. The dialysis catheter is then connected to the hemodialysis machine for the next dialysis treatment. It should be noted that although the aspiration of antithrombotic drugs from the third flow channel 13 and the occlusion balloon 30 involves an additional step compared to traditional antithrombotic procedures, it effectively prevents thrombus formation at the tip of the catheter body 10, ensuring vascular access.

[0045] Compared with existing technologies, the advantages of using the anti-thrombotic dialysis catheter shown in this embodiment are as follows: By forming a first, second, and third flow channel inside the catheter body, and by installing one-way valves at both ends of the third flow channel on the catheter body for the one-way passage of antithrombotic drugs, as well as occlusion balloons for storing and releasing antithrombotic drugs, when dialysis treatment is not being performed and the dialysis catheter is left in the body, antithrombotic drugs are injected into the one-way valves. The antithrombotic drugs will enter the occlusion balloon along the third flow channel. The occlusion balloon gradually inflates, and the inflated occlusion balloon will block the first and second flow channels, isolating the first and second flow channels from the patient's blood vessels. Blood will no longer enter the first and second flow channels, preventing thrombus formation inside the catheter. At the same time, the antithrombotic drugs are slowly released through the microporous structure on the surface of the occlusion balloon and / or the microporous structure on the surface of the catheter body that connects to the third flow channel. This can eliminate thrombi formed at the catheter tip due to the anchoring effect caused by the dead point at the dialysis catheter tip, as well as thrombi formed on the catheter surface. Therefore, the dialysis catheter shown in this embodiment can effectively prevent thrombosis compared to traditional long-term dialysis catheters. It is consistent in terms of catheter placement, use, and maintenance, requires no other consumables, and will not increase the economic burden on patients.

[0046] Example 2 The second embodiment of the present invention also provides a dialysis catheter for preventing thrombosis. The dialysis catheter shown in this embodiment is structurally similar to the dialysis catheter shown in the first embodiment, except that: In this embodiment, the catheter body is provided with a microporous structure that communicates with the third flow channel. That is, both the occlusion balloon and the catheter body are provided with a through microporous structure, so as to simultaneously be used for the sustained release of antithrombotic drugs.

[0047] During use, when hemodialysis is not being performed, antithrombotic drugs are injected into the occlusion balloon through the one-way valve and the third channel, causing the occlusion balloon to inflate. The inflated occlusion balloon then blocks the first and second channels. The antithrombotic drugs in the third channel are released outward through the microporous structure of the occlusion balloon, effectively preventing thrombus formation at the tip of the catheter body. Furthermore, the drugs are released outward through the microporous structure on the catheter body connected to the third channel, effectively preventing thrombus formation on the outer surface of the catheter body. Compared to the dialysis catheter shown in the first embodiment, the effect of preventing thrombus formation is better.

[0048] Example 3 The third embodiment of the present invention also provides a dialysis catheter for preventing thrombosis. The dialysis catheter shown in this embodiment is structurally similar to the dialysis catheter shown in the first embodiment, except that: In this embodiment, the catheter body has a microporous structure that communicates with the third flow channel, while the surface of the occlusion balloon has no microporous structure, meaning that the antithrombotic drug is released only through the sidewall of the catheter body.

[0049] During use, when hemodialysis is not being performed, the antithrombotic drug is injected into the occlusion balloon through the one-way valve and the third channel, causing the occlusion balloon to inflate. The inflated occlusion balloon then blocks the first and second channels respectively. The antithrombotic drug in the third channel is released outward through the microporous structure on the catheter body that connects to the third channel, which can effectively prevent thrombus formation on the outer surface of the catheter body. Compared with the dialysis catheter shown in the first embodiment, the effect of preventing thrombus formation is similar.

[0050] Example 4 Please refer to this carefully. Figures 3-6 The fourth embodiment of the present invention also provides a dialysis catheter for preventing thrombosis. The dialysis catheter shown in this embodiment has the same structure as the dialysis catheter shown in the first embodiment, except that in this embodiment: An elastic balloon 40 is also connected in series between the one-way valve 20 and the catheter body 10. The one-way valve 20 is connected to the third flow channel 13 of the catheter body 10 through the elastic balloon 40 and the balloon catheter 41.

[0051] In this embodiment, an elastic balloon 40 is provided at the front end of the one-way valve 20. During use, when antithrombotic drugs are injected into the one-way valve 20, the elastic balloon 40 inflates together with the occlusion balloon 30. As time goes by, the internal antithrombotic drugs slowly permeate outward through the microporous structure on the surface of the occlusion balloon 30. As the amount of antithrombotic drugs decreases, the elastic balloon 40, being softer than the occlusion balloon 30, deflates before the occlusion balloon 30, thus ensuring sufficient pressure inside the occlusion balloon 30 before the patient's next dialysis treatment. The first flow channel 11 and the second flow channel 12 of the catheter body can be completely sealed and leak-free.

[0052] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. 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.

[0053] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A dialysis catheter for preventing thrombosis, characterized in that, The dialysis catheter includes: The catheter body has a first flow channel, a second flow channel and a third flow channel running through it along its axis. The first flow channel and the second flow channel are used for blood drawing and blood return during dialysis, respectively. A one-way valve and an occlusion balloon are respectively connected to the input and output ends of the third flow channel in the catheter body. The third flow channel is used to deliver antithrombotic drugs. The one-way valve includes a valve body, a valve core disposed within the valve body, and an elastic element for supporting the valve core. The valve body is connected to the third flow channel through a through-flow valve body channel. The elastic element and the valve core are positioned in a supporting position within the valve body channel to unidirectionally close the valve body channel. An elastic balloon is also connected in series between the one-way valve and the catheter body. The one-way valve is connected to the third flow channel through the elastic balloon and the balloon catheter. The occlusion balloon and / or the catheter body have a perforated microporous structure communicating with the third flow channel. When the antithrombotic drug is injected through the one-way valve and gradually flows into the occlusion balloon through the third flow channel, the occlusion balloon changes to an inflated state, so that the inflated occlusion balloon seals the first flow channel and the second flow channel. The microporous structure on the surface of the occlusion balloon and / or the catheter body gradually releases the antithrombotic drug into the body.

2. The dialysis catheter for preventing thrombosis according to claim 1, characterized in that, The first flow channel, the second flow channel, and the third flow channel are all recessed within the catheter body to form a receiving space within the catheter body for accommodating the occlusion balloon. The occlusion balloon is connected to the third flow channel to restrict the axial degree of freedom of the occlusion balloon.

3. The dialysis catheter for preventing thrombosis according to claim 1, characterized in that, A positioning assembly is provided between the occlusion balloon and the inner wall of the catheter body, including a first positioning element and a second positioning element. The first positioning element and the second positioning element cooperate with each other to position the occlusion balloon, thereby restricting the radial degree of freedom of the occlusion balloon.

4. The dialysis catheter for preventing thrombosis according to claim 3, characterized in that, The first positioning element is protruding and located on the outside of the occlusion balloon, and the second positioning element is recessed and located on the inner side wall of the catheter body. The first positioning element is inserted into the second positioning element.

5. The dialysis catheter for preventing thrombosis according to claim 4, characterized in that, The outer side of the occlusion balloon is provided with two first positioning elements, and the inner side wall of the catheter body is provided with two second positioning elements corresponding to the first positioning elements respectively.

6. The dialysis catheter for preventing thrombosis according to claim 1, characterized in that, The third flow channel is located between the first flow channel and the second flow channel, and the expansion of the occlusion balloon will seal the first flow channel and the second flow channel located on both sides.

7. The dialysis catheter for preventing thrombosis according to claim 6, characterized in that, The catheter body has a first notch communicating with the first flow channel and a second notch communicating with the second flow channel on the outside of the occlusion balloon.

8. The dialysis catheter for preventing thrombosis according to any one of claims 1-7, characterized in that, The occlusion balloon is flat in its initial state.

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