Fixing cannula for establishing blood passage
Through the combination of a bent design fixed cannulation and expansion parts, the problem of difficulty and easy displacement of the cannulation in the atrial septum is solved, achieving more stable blood pathway establishment and cardiac assisted blood pumping function.
Patent Information
- Application Number
- CN202420063067.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-10
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2034-01-10
AI Technical Summary
The existing left heart assistive device cannula is difficult to puncture the atrial septum, easily damage the inner wall of the ventricle, and easily displaces under the influence of blood flow, affecting the treatment effect.
A fixed cannula with a bend angle is designed with an expansion member to fix the position after the atrial septum puncture, preventing the cannula from displaced, including a curved reinforcement tube and expansion member, through the blood flow through the opening into the first passage and through the The second passage provides fluid to the expansion member to expand it and is fixed to both sides of the diaphragm.
The bending design facilitates atrial septum puncture, reduces damage to the atrial wall, and prevents the cannula from displaced during work through the fixing effect of the expansion member, improving the stability and effectiveness of the treatment.
Smart Images
Figure CN222150106U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of cannulae, and in particular to a fixed cannula. Background Art
[0002] The incidence of cardiovascular diseases in humans is increasing. Heart failure is the most common cardiovascular disease and has a high mortality rate. Among them, heart failure is mainly left heart failure, which refers to heart failure caused by left ventricular compensatory dysfunction, which is very common in clinical practice. Heart transplantation is the most effective way to treat advanced heart failure, but due to the limited number of heart donors and the individual surgical tolerance of patients, heart transplantation is rarely performed in clinical practice. In recent years, left ventricular assist devices for the treatment of heart failure have developed rapidly. This device uses a cannula to enter the right atrium through the femoral vein, and then enters the left atrium through atrial septal puncture. After the blood in the left atrium is drawn out by a pump, it is sent back to the human aorta through an arterial cannula, thereby partially or completely replacing the heart's pumping function. The left ventricular assist device has a good effect on the treatment of heart failure, but there are some problems with the cannula for left heart blood extraction in clinical use, such as difficulty in atrial septal puncture, easy damage to the ventricular wall, and cannula displacement. The traditional cannula body is straight and slender, which makes it difficult to complete atrial septal puncture at the distal end of the cannula in the blood vessel. At the same time, there is a large radial force at the atrial septum of the straight cannula, which can easily cause damage to the inner wall of the ventricle. In addition, the cannula structure design makes it easy for the cannula to shift inside the atrium. When the cannula is sucking blood in the left heart, it is affected by the blood flow, and the distal end of the cannula is prone to swing and cause the cannula body to move, affecting the treatment effect. Therefore, it is urgent to improve the cannula to ensure that the cannula is easy to puncture the atrial septum and the position is fixed when it is used. Prevent it from shifting during operation and affecting the heart's pumping blood. Utility Model Content
[0003] The present application mainly provides a fixed cannula for establishing a blood access. The bending angle design facilitates atrial septal puncture, increases the effectiveness of atrial septal puncture, and can effectively position after successful puncture to prevent the fixed cannula from shifting.
[0004] In order to solve the above technical problems, the technical solution adopted in the present application is: to provide a fixed cannula for establishing a blood passage, comprising a tube body, a first channel and a second channel, the first channel and the second channel are not connected to each other, the tube body is provided with an opening, and the fixed cannula also includes: an expansion member, which is arranged on the periphery of the tube body and has an initial state and an expanded state; the second channel is connected to the expansion member and is used to provide fluid for the expansion of the expansion member; when the fixed cannula passes through the diaphragm opening and is positioned on both sides of the diaphragm, blood enters the first channel from the opening and flows through the fixed cannula to realize the transportation of blood from one side of the diaphragm to the other side; the second channel provides fluid to the expansion member, the expansion member expands and is fixed on at least one side of the diaphragm to limit the displacement of the fixed cannula; at least one of the expansion member, the first channel and the second channel is provided.
[0005] The tube body includes: a drainage tube and a reinforcement tube, wherein the drainage tube is arranged at the distal end of the reinforcement tube, and the distal end is the end away from the operator; the opening is arranged on the drainage tube; the first channel and the second channel are arranged inside the reinforcement tube, the drainage tube is connected with the first channel, and the blood enters the drainage tube from the opening and then flows into the first channel;
[0006] The opening is an opening disposed at the farthest end of the drainage tube and / or a side hole on the side wall of the drainage tube;
[0007] One end of the reinforcement tube connected to the drainage tube is in a bent structure, which is used to better position the fixed cannula at the target position.
[0008] Among them, the fixed cannula also includes a developing structure, which is arranged on the drainage tube, the expansion piece, the bending structure, and at least one place of the reinforcement tube to indicate the position of the fixed cannula. The developing structure is a continuous film layer that can be developed, or the developing structure includes multiple developing marking rings, and the multiple developing marking rings are arranged at equal intervals.
[0009] There are two expansion pieces and two second channels, and the two expansion pieces are arranged at intervals on the periphery of one end where the reinforcing tube is connected to the drainage tube, and the two expansion pieces are respectively connected to one second channel.
[0010] The connector is connected to the other end of the reinforcement tube away from the drainage tube, and the connector is a hollow structure and communicates with the reinforcement tube; the reducer connects the reinforcement tube and the connector, and the reducer is a hollow structure and communicates with the reinforcement tube and the connector;
[0011] The first channel and the second channel are arranged inside the reinforcing tube and / or the reducing tube.
[0012] Wherein, one end of the second channel away from the expansion piece is connected with a one-way valve for controlling the opening and closing of the second channel.
[0013] The tube body is a double-cavity or multi-cavity tube body, the first channel and the second channel are integrally formed with the tube body, and the first channel and the second channel are cavities accommodated in the tube body.
[0014] The first channel is a cavity contained in the tube body, and the second channel is an independent tube nested in the tube body and / or outside the tube body.
[0015] Among them, the reinforcement tube includes at least a support layer, at least part of the support layer is a metal wire woven structure, and / or at least part of the support layer is a metal wire spirally wound structure; and a first flexible layer arranged on the outside of the support layer and / or a second flexible layer arranged on the inside of the support layer.
[0016] Wherein, the drainage tube further includes a third flexible layer arranged on the outside of the developing structure and / or a fourth flexible layer arranged on the inside of the developing structure.
[0017] The beneficial effects of the present application are as follows: in the fixed cannula of the present application, the curved design makes it easier for the fixed cannula body to achieve atrial septal puncture so that the fixed cannula can be positioned in the atrial position, reducing damage to the atrial wall; through the use of the expansion piece, after the expansion piece expands during use, the position of the fixed cannula can be effectively fixed to prevent it from moving between the left atrium and the right atrium, thereby facilitating the fixed cannula to achieve its auxiliary role in the ventricular assist device. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:
[0019] Figure 1 This is a structural schematic diagram of an implementation method of a fixed cannula in this application;
[0020] Figure 2 A cross-sectional view of an embodiment of a fixed cannula in the present application;
[0021] Figure 3 This is a structural schematic diagram of an implementation method of the expansion member in this application;
[0022] Figure 4 It is a cross-sectional view of an embodiment of a reinforcement tube in the present application;
[0023] Figure 5 A cross-sectional view of an embodiment of a reinforced tube side wall in the present application;
[0024] Figure 6 A cross-sectional view of an embodiment of a side wall of a drainage tube in the present application;
[0025] Explanation of the reference numerals: 100 fixed cannula; 1 drainage tube; 11 third flexible layer; 12 fourth flexible layer; 13 developing layer; 14 opening; 2 reinforcing tube; 20 first channel; 21 first flexible layer; 22 second flexible layer; 23 supporting layer; 3 expansion piece; 30 second channel; 34 one-way valve; 35 first expansion piece; 36 second expansion piece; 4 connector; 5 reducer; 6 left atrium; 7 right atrium; 8 atrial septum. DETAILED DESCRIPTION
[0026] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.
[0028] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.
[0029] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.
[0030] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.
[0031] See also Figure 1 and Figure 2 The present application provides a fixed cannula 100 that is easy to fix for establishing a blood passage. The fixed cannula 100 is generally positioned on both sides of a diaphragm. The two sides of the diaphragm are two independent chambers. The fixed cannula 100 passes through the diaphragm and is positioned at both ends of the diaphragm, so as to form a blood passage from one side of the diaphragm to the other side of the diaphragm. The fixed cannula 100 includes a tube body, a first channel 20 and a second channel 30. The first channel 20 and the second channel 30 are independent of each other and not connected to each other. The first channel 20 is used for blood circulation, and the second channel 30 is used for other fluid circulation. The fluids in the two channels do not interfere with each other. The tube body is provided with an opening 14. The fixed cannula 100 also includes: an expansion member 3, which is arranged on the periphery of the tube body and has an initial state and an expansion state. The second channel 30 is connected to the expansion member 3 and is used to provide fluid for the expansion of the expansion member 3.
[0032] When the fixed cannula 100 passes through the septum opening and is positioned on both sides of the septum, blood enters the first channel 20 from the opening 14 and flows through the fixed cannula 100 to achieve blood transportation from one side of the septum to the other side; the second channel 30 provides fluid to the expansion member 3, and the expansion member 3 expands and is fixed on at least one side of the septum to limit the displacement of the fixed cannula 100. In the embodiment of the present application, the septum refers to the atrial septum. Of course, it may also include other septa, such as the ventricular septum.
[0033] In the above embodiment, the expansion member 3 does not expand in the initial state, and the radial dimension of the expansion member 3 is not larger than the radial dimension of the fixed cannula 100 itself. When the fixed cannula 100 passes through the diaphragm opening and enters the other side of the diaphragm from one side of the diaphragm, the second channel 30 provides fluid to the expansion member 3, and the expansion member 3 expands. The size of the expansion member 3 is larger than the size of the fixed cannula 100, and the fixed cannula 100 can no longer return from the other side of the diaphragm to the one side of the diaphragm, thereby achieving the fixation of the fixed cannula 100 on both sides of the diaphragm.
[0034] In the embodiment of the present application, the tube body includes a drainage tube 1 and a reinforcement tube 2, wherein the drainage tube 1 is arranged at the distal end of the reinforcement tube 2, and the distal end is the end away from the operator; the opening 14 is arranged on the drainage tube 1, the drainage tube 11 is a hollow structure, the first channel 20 and the second channel 30 are arranged inside the reinforcement tube 2, and the drainage tube 1 is connected to the first channel 20, and blood can enter the drainage tube 1 from the opening 14 and then flow into the first channel 20 to achieve blood transportation. Among them, the opening 14 of the drainage tube 1 can be an opening arranged at the farthest end of the drainage tube 1, or the opening 14 of the drainage tube 1 is a side hole arranged on the side wall of the drainage tube 1, or the opening 14 includes both the opening at the far end of the drainage tube 1 and the side hole on the side wall of the drainage tube 1, as long as the blood diversion effect can be achieved.
[0035] Please continue reading Figure 1 and Figure 2 , the drainage tube 1 is provided with at least one opening 14, and the opening 14 can be an opening arranged at the farthest end of the drainage tube 1, the opening is connected to the inside of the drainage tube 1, and the opening diameter is not larger than the inner diameter of the drainage tube 1: that is, the opening diameter can be smaller than the inner diameter of the drainage tube 1, or the opening diameter can be the same as the diameter of the drainage tube 1. When the drainage tube 1 is a tube with no dimensional change throughout, the inner diameter of the drainage tube 1 is the same throughout, and the opening diameter is the same as the inner diameter of the drainage tube 1; when the distal opening of the drainage tube 1 is a tapered structure, the opening diameter is smaller than the diameter of the drainage tube 1. The embodiment of the present application does not impose specific restrictions on the opening size, as long as the drainage tube 1 can pass through the diaphragm opening smoothly and the blood can be successfully drained into the drainage tube 1.
[0036] In another embodiment, the opening 14 may be a side hole located on the wall of the drainage tube 1, and the side hole is in communication with the interior of the drainage tube 11. Specifically, the wall of the drainage tube 11 is provided with one, two, three or more side holes. When the wall of the drainage tube 11 includes multiple side holes, the multiple side holes may be arranged on the circumference of the drainage tube 11, and the edge of the side hole and the main body of the drainage tube 11 are smoothly transitioned, so that blood can flow smoothly into the side hole, reducing the risk of blood accumulation there, and ensuring that there is sufficient flow when the fixed cannula 100 draws blood.
[0037] The drainage tube 1 and the reinforcement tube 2 are connected by welding, or the drainage tube 1 and the reinforcement tube 2 are integrally formed. Specifically, the drainage tube 1 and the reinforcement tube 2 are welded, the connection method is simple, and it is easy to prepare. In other embodiments, the drainage tube 1 and the reinforcement tube 2 are integrally formed, which can reduce the pipeline connection and avoid blood accumulation when blood flows through the pipeline connection.
[0038] Please continue reading Figure 1 and Figure 2The end of the reinforcement tube 2 connected to the drainage tube 1 is in a curved structure, and the bending angle ranges from 0 to 90 degrees. Specifically, the side of the reinforcement tube 2 in the fixed cannula 100 close to the drainage tube 1 adopts a curved design. Compared with the existing straight cannula, the distal curved fixed cannula 100 is easier to complete the puncture of the atrial septum 8 to reach the left atrium 6. At the same time, the distal curved design of the fixed cannula 100 can also prevent the fixed cannula 100 from directly contacting the ventricular wall during high-speed blood extraction, thereby avoiding causing ventricular wall damage and endangering the patient's life.
[0039] In one embodiment, the bending angle of the curved portion in the reinforcing tube 2 is preferably 40-80°, wherein the bending angle of the curved portion in the reinforcing tube 2 may be 40°, 45°, 50°, ... or 80°. The above angle design facilitates the clinical fixation of the cannula 100 for puncturing the atrial septum 8, and effectively prevents the fixation of the cannula 100 from damaging the inner wall of the left atrium 6. When the bending angle of the curved portion in the reinforcing tube 2 is 60°, the use effect is better.
[0040] The expansion member 3 is arranged at the periphery of the end where the reinforcement tube 2 is connected to the drainage tube 1, and has an initial state and a filled state. When the expansion member 3 is filled, the expansion member 3 is used to fix the position of the fixed cannula 100 and limit the displacement of the fixed cannula 100; the second channel 30 is a hollow structure and is connected to the expansion member 3, and the second channel 30 is used to provide a fluid channel for the filling and contraction of the expansion member 3. Specifically, the drainage tube 1 and the reinforcement tube 2 are both hollow structures, one end of the reinforcement tube 2 is connected to the drainage tube 1, and the reinforcement tube 2 is connected to the drainage tube 1. The expansion member 3 is arranged at the periphery of the end where the reinforcement tube 2 is connected to the drainage tube 1, that is, the expansion member 3 is located on the side of the reinforcement tube 2 close to the drainage tube 1. The second channel 30 is a hollow structure and is connected to the expansion member 3. The second channel 30 transports fluid or gas to the expansion member 3 to expand the expansion member 3. After the expansion member 3 is expanded, the position of the drainage tube 1 can be fixed, and then the position of the fixed cannula 100 can be effectively fixed, which is convenient for the application of the fixed cannula 100.
[0041] See also Figure 1 and Figure 2 The expansion member 3 is arranged around the reinforcing tube 2. When the expansion member 3 is filled, the radial diameter of the expansion member 3 is not less than the radial diameter of the fixed cannula 100. When the expansion member 3 is expanded, the bulging expansion member 3 surrounds the reinforcing tube 2 for a week to play a fixing role. In one embodiment, the expansion member 3 may not be arranged around the reinforcing tube 2. For example, the expansion member 3 may be arranged on a part of the side of the reinforcing tube 2. For example, after the expansion member 3 is expanded, it may be a convex block or slope located on the side of the reinforcing tube 2.
[0042] See also Figure 2 and Figure 3, the number of expansion members 3 is two, and the two expansion members 3 are arranged at intervals on the periphery of one end of the reinforcing tube 2 connected to the drainage tube 1, and the two expansion members 3 are each connected to a second channel. Specifically, the number of expansion members 3 is two, and they are respectively connected to a second channel 30. At this time, fluid or gas is transported to different expansion members 3 through different second channels 30 to fill the expansion members 3. In actual use, the fixed cannula 100 enters the right atrium 7 through the femoral vein, and then enters the left atrium 6 through the atrial septum 8. When the fixed cannula 100 completes the atrial septum 8 puncture and reaches the correct position, the expansion member 3 can be filled, and the first expansion member 35 and the second expansion member 36 are respectively opened on both sides of the atrial septum 8, wherein the first expansion member 35 is located in the left atrium 6, and the second expansion member 36 is located in the right atrium 7. The expansion member 3 plays a role in fixing the position of the fixed cannula 100 to prevent displacement. Of course, in this application, at least one of the first expansion member 35 and the second expansion member 36 is expanded to meet the function of fixing the fixed cannula 100 to prevent displacement.
[0043] In one embodiment, in order to ensure the effect of the expansion member 3 in fixing the cannula 100, the interval between the two expansion members 3 is 3mm-5mm. Specifically, the interval between the two expansion members 3 can be 3mm, 4mm or 5mm.
[0044] In one embodiment, the tube body is configured as a double-lumen or multi-lumen tube body. In the present application, three independent lumens are integrally formed inside the reinforcing tube 2, one of which is a first channel 20, i.e., a channel for blood flow, and the other two lumens are second channels 30, which are used to transport fluid for expansion to the two expansion members 3, which can be gas or liquid. Please continue to read Figure 1 and Figure 2 and Figure 4 , one end of the second channel 30 communicating with the expansion member 3 is located in the inner cavity of the reinforcing tube 2, and the first channel 20 and the second channel 30 are independent of each other and do not interfere with each other in function. In a certain embodiment, only one expansion member 3 may be provided for fixation, and correspondingly, two lumens are provided inside the reinforcing tube 2, one of which is the first channel 20 for blood circulation, and the other second channel 30 is used to provide liquid for expansion of the expansion member 3. Similarly, multiple expansion members 3 may be provided for fixation, and the number of expansion members 3 may be set to three, four or more, which is not specifically limited in this application. When two or more independent lumens are integrally formed inside the reinforcing tube 2, the connection method of the expansion member 3 and the expansion fluid lumen wall of the reinforcing tube 2 may be integrally formed or may be other methods that can realize the connection between the expansion member 3 and the expansion fluid lumen of the reinforcing tube 2. The above design can set the main structure of the second channel 30 inside the reinforcing tube 2, which can ensure the compactness of the structure of the fixed cannula 100, while ensuring the smoothness of the outer side of the fixed cannula 100, which is convenient for use.
[0045] In other embodiments, the first channel 20 is a cavity accommodated in the body of the reinforcement tube 2, the second channel 30 is an independent tube, the second channel 30 can be a delivery tube, the delivery tube is nested in the reinforcement tube 2, and presents a composite casing structure, the delivery tube can be one, two or more, and the delivery tubes are all connected to the expansion member 3 to provide the expansion member 3 with a fluid for expansion. In particular, the delivery tube can also be separately arranged outside the reinforcement tube 2 and communicated with the expansion member 3, and the delivery tube and the tube cavity of the reinforcement tube 2 are arranged in parallel.
[0046] Please continue reading Figure 1 , Figure 2 and Figure 4 , the other end of the second channel 30 is connected to a one-way valve 34 for controlling the conduction and closing of the second channel 30. Specifically, the one-way valve 34 can control the conduction and closing of the second channel 30. When the one-way valve 34 controls the conduction of the second channel 30, the one-way valve 34 can transport fluid or gas to the expansion member 3 through the second channel 30 to fill the expansion member 3, or the one-way valve 34 can guide the fluid or gas in the expansion member 3 through the second channel 30 to shrink the filled expansion member 3. When the one-way valve 34 controls the closing of the second channel 30, the one-way valve 34 stops transporting or guiding fluid or gas to the expansion member 3 through the second channel 30, so that the expansion member 3 maintains the original state.
[0047] In one embodiment, the fixed cannula 100 further includes a developing structure, which is arranged at least one of the drainage tube 1, the expansion member 3, the bending structure and the reinforcement tube 2. The developing structure is arranged at the drainage tube 1 to indicate the insertion position of the fixed cannula 100 in the left atrium, so as to prevent the distal structure of the drainage tube from damaging the inner wall of the atrium; the developing structure is arranged at the expansion member 3 to indicate the position of the expansion member 3, so as to facilitate the fixed cannula 100 to determine the correct fixed position; when the developing structure is arranged at the bending structure or at the reinforcement tube, it is used to indicate the position of the bending structure of the fixed cannula and the position of the tube body of the reinforcement tube, so as to facilitate the indication of the distance between the fixed cannula 100 and the target atrium position. The developing structure is a continuous film layer capable of developing, or the developing structure includes a plurality of developing marker rings, and the plurality of developing marker rings are arranged at equal intervals.
[0048] See also Figure 6, the drainage tube 1 at least includes a developing layer 13, and the developing layer 13 is a continuous film layer capable of development, or the developing layer 13 includes a plurality of developing marking rings, and the plurality of developing marking rings are arranged at equal intervals. The design of the developing layer 13 enables the drainage tube 1 to be developed under X-rays, and can be used to track and observe the position of the fixed cannula 100 in the blood vessel. In one embodiment, the developing layer 13 is a continuous film layer capable of development. In another embodiment, the developing layer 13 includes a plurality of developing marking rings. Specifically, when the developing layer 13 is a continuous film layer capable of development, the developing layer 13 can be formed of a heavy metal substance that is opaque to X-rays, so as to increase the visibility of the fixed cannula 100 under X-rays. In addition, when the developing layer 13 is a developing marking ring, and the distances between adjacent developing marking rings are the same, it can be used to accurately mark the position of the head end of the drainage tube 1 in the fixed cannula 100.
[0049] See also Figure 5 The reinforcing tube 2 at least includes a supporting layer 23. In one embodiment, at least part of the supporting layer 23 is in a braided structure. In another embodiment, at least part of the supporting layer 23 is in a spirally wound structure. In another embodiment, part of the supporting layer 23 is in a braided structure and part of the supporting layer 23 is in a spirally wound structure. When the supporting layer 23 adopts a braided structure or a spirally wound structure or a combination of a braided structure and a spirally wound structure, the supporting effect is better.
[0050] In one embodiment, the material in the support layer 23 is stainless steel wire. Of course, the material of the support layer 23 can also be other metal wires. The support layer 23 is stainless steel wire, which can provide sufficient radial support for the reinforcing tube 2 to ensure that the fixed cannula 100 smoothly enters the designated position in the blood vessel and provides a reliable blood channel. In one embodiment, the stainless steel wire can adopt a braided structure, which has good pushing performance and is easy to deliver the fixed cannula 100 to the target position. In another embodiment, the stainless steel wire can also adopt a spiral winding structure, which has good compliance and is not easy to damage the blood vessel. In another embodiment, the stainless steel wire can adopt a structure that combines braiding and spiral winding, which not only achieves good pushing performance, but also avoids unnecessary damage to the blood vessel during the transportation of the fixed cannula 100.
[0051] In one embodiment, the support layer 23 includes a first sub-support layer and a second sub-support layer which are connected to each other, wherein the first sub-support layer is arranged adjacent to the drainage tube 1, wherein the first sub-support layer is in a spiral winding structure, and the second sub-support layer is in a braided structure. Specifically, the side of the reinforcement tube 2 close to the drainage tube 1 is spirally wound, and the rest of the part is braided. The design of the spiral winding is to avoid damage to the right atrium 7 by the fixed cannula 100. The braiding density of the braided structure and the winding density of the spiral winding are adjustable, with a density of 50-200 PPI, and irregular gradients can be generated from the distal end to the proximal end of the reinforcement tube 2 to achieve adjustable support for different sections of the reinforcement tube 2. The braided wire can be selected from a circular, flat or other structure. In one embodiment, the braided wire can be selected from a circular structure, and the circular braided wire can more evenly increase the connection effect of the gradient structure than the flat braided wire.
[0052] In one embodiment, the reinforcing tube 2 further includes a first flexible layer 21 disposed on the outside of the supporting layer 23 and a second flexible layer 22 disposed on the inside of the supporting layer 23. Alternatively, the reinforcing tube 2 includes only one of the first flexible layer 21 disposed on the outside of the supporting layer 23 and the second flexible layer 22 disposed on the inside of the supporting layer 23. The first flexible layer 21 and the second flexible layer 22 can be made of thermoplastic polyurethane (TPU) material, so that the reinforcing tube 2 is flexible and easy to use.
[0053] See also Figure 6 , the drainage tube 1 further includes a third flexible layer 11 disposed on the outside of the developing layer 13 and a fourth flexible layer 12 disposed on the inside of the developing layer 13. Alternatively, the drainage tube 1 includes only one of the third flexible layer 11 disposed on the outside of the developing layer 13 and the fourth flexible layer 12 disposed on the inside of the developing layer 13. When the drainage tube 1 includes the third flexible layer 11 disposed on the outside of the developing layer 13, the fourth flexible layer 12 disposed on the inside of the developing layer 13, and the developing layer 13 located in the middle, the third flexible layer 11, the developing layer 13, and the fourth flexible layer 12 are stacked. The third flexible layer 11 and the fourth flexible layer 12 can be made of thermoplastic polyurethane (TPU) material, so that the drainage tube 1 is flexible and avoids damaging the inner wall of the left atrium 6.
[0054] Please continue reading Figure 1 and Figure 2, the fixed cannula 100 further includes a connector 4 and a reducer 5, wherein the connector 4 is connected to the other end of the reinforcement tube 2 away from the drainage tube, and the connector 4 is a hollow structure and communicates with the reinforcement tube 2; the reducer 5 connects the reinforcement tube 2 and the connector 4, and the reducer 5 is a hollow structure and communicates with the reinforcement tube 2 and the connector 4. Specifically, the reducer 5 plays the role of transition between the reinforcement tube 2 and the connector 4. The function of the connector 4 is to connect the fixed cannula 100 to the left ventricular assist therapy device. Both the connector 4 and the reducer 5 are hollow structures, which facilitates the flow of blood in the fixed cannula 100. In another embodiment, the first channel and the second channel can also be arranged inside the reducer, or the first channel and the second channel are simultaneously arranged inside the reinforcement tube and the reducer, that is, the first channel and the second channel extend from the inside of the reinforcement tube to the reducer until they extend out of the reducer.
[0055] In one embodiment, an anticoagulant coating may be added to the outside of the fixed cannula 100. The anticoagulant coating may be located on the outside of at least one of the drainage tube 1 and the reinforcement tube 2. The design of the anticoagulant coating may block the coagulation path, normalize the surrounding tissue of the implanted cannula, and make the application of the fixed cannula 100 safer.
[0056] In order to better understand the structure of the above-mentioned fixed cannula 100, the following describes its use method:
[0057] There are two expansion pieces 3 on one side of the reinforcement tube 2 close to the drainage tube 1. When the fixed cannula 100 completes the puncture of the atrial septum 8 and reaches the correct position, the expansion piece 3 can be filled by the one-way valve 34. The expanded expansion pieces 3 are respectively located on both sides of the atrial septum 8, which can fix the fixed cannula 100 to prevent the fixed cannula 100 from shifting.
[0058] At the same time, the reinforcing tube 2 of the fixed cannula 100 has three channels inside, which are not connected to each other. Figure 4As shown. One of the second channels 30 is a filling channel for the first expansion member 35. One end of the second channel 30 is connected to the first expansion member 35, and the other end is connected to the one-way valve 34. Liquid can be injected into the second channel 30 through the one-way valve 34 to control the filling of the first expansion member 35. Another second channel 30 is a filling channel for the second expansion member 36. One end of the second channel 30 is connected to the second expansion member 36, and the other end is connected to the one-way valve 34. Liquid is injected into the other second channel 30 through the one-way valve 34 to control the filling of the second expansion member 36. In the above embodiment, the first expansion member 35 and the second expansion member 36 are both balloons, and the balloons are expanded by filling with liquid. In other embodiments, the first expansion member 35 and the second expansion member 36 are both airbags, and the airbags are expanded by filling with gas. In other embodiments, one of the first expansion member 35 and the second expansion member 36 is an airbag, and the other is a balloon. The first channel 20 of the reinforcement tube 2 is a blood flow channel, blood is introduced from the drainage tube 1, and blood is led out from the connector 4. In the initial state, the outer diameter of the first expansion member 35 and the second expansion member 36 is the same as the tube wall of the reinforcement tube 2 close to the drainage tube 1. When the drainage tube 1 of the fixed cannula 100 is accurately positioned in the left atrium 6, liquid or gas is input into the first expansion member 35 and the second expansion member 36. After the first expansion member 35 and the second expansion member 36 are expanded, they are respectively positioned on both sides of the atrial septum 8 to fix the fixed cannula 100.
[0059] Before the atrial septum 8 is punctured, the expansion member 3 is in an initial state, and the radial diameter of the expansion member 3 is not larger than the radial diameter of the fixed cannula 100 itself, so that the fixed cannula 100 can move in the blood vessel easily, so as to avoid scratching the blood vessel when the fixed cannula 100 moves inside the blood vessel. The radial diameter of the expansion member 3 can be smaller than the radial diameter of the fixed cannula 100 itself. Preferably, the radial diameter of the expansion member 3 is the same as the radial diameter of the fixed cannula 100 itself. The advantages of such a design are: first, it is convenient for the fixed cannula 100 to pass through the atrial septum 8 more smoothly when the atrial septum 8 is punctured, and there will be no jamming or other phenomena due to the presence of the expansion member 3; second, it makes the transition between the fixed cannula 100 and the expansion member 3 smoother, so that the accumulation of blood can be minimized when the blood flows through the transition position between the fixed cannula 100 and the expansion member 3.
[0060] Specifically, the working process of the fixed cannula in the present application is as follows: after the fixed cannula 100 reaches the right atrium 7 through the femoral vein, the atrial septum 8 puncture is performed, so that the drainage tube 1 and part of the reinforcement tube 2 of the fixed cannula 100 enter the left atrium 6. After the fixed cannula 100 completes the atrial septum 8 puncture and reaches the correct position, the operator first uses a syringe to connect the one-way valve 34, and the liquid or gas reaches the first expansion member 35 through the second channel 30 and fills it. At this time, the first expansion member 35 located on one side of the left atrium 6 has expanded. Then use a syringe to connect another one-way valve 34, and the liquid or gas reaches the second expansion member 36 through another second channel 30 and fills it. At this time, the second expansion member 36 located on one side of the right atrium 7 has expanded. After the first expansion member 35 and the second expansion member 36 are filled on both sides of the atrial septum 8, they play a role in fixing the fixed cannula 100.
[0061] Then, the connector 4 of the fixed cannula 100 is connected to the left heart assist treatment device pipeline, and the blood in the left atrium 6 is sucked out by the operation of the pump, and then the blood is returned to the human aorta through the arterial fixed cannula 100, thereby playing a role of partially or completely replacing the heart and maintaining the stability of the body's circulatory system.
[0062] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.
Claims
1. A fixed cannula for establishing a blood access, comprising a tube body, a first channel and a second channel, wherein the first channel and the second channel are not connected to each other, and the tube body is provided with an opening, characterized in that: The fixed cannula further includes: an expansion member, which is arranged at the periphery of the tube body and has an initial state and an expansion state; the second channel is communicated with the expansion member and is used to provide fluid for the expansion of the expansion member; When the fixed cannula passes through the diaphragm opening and is positioned on both sides of the diaphragm, blood enters the first channel from the opening and flows through the fixed cannula to achieve the transportation of blood from one side of the diaphragm to the other side; the second channel provides fluid to the expansion member, and the expansion member expands and is fixed on at least one side of the diaphragm to limit the displacement of the fixed cannula; at least one of the expansion member, the first channel and the second channel is provided.
2. The fixed cannula according to claim 1, characterized in that: The tube body comprises: a drainage tube and a reinforcement tube, wherein the drainage tube is arranged at the distal end of the reinforcement tube, and the distal end is the end away from the operator; the opening is arranged on the drainage tube; the first channel and the second channel are arranged inside the reinforcement tube, the drainage tube is connected with the first channel, and blood enters the drainage tube from the opening and then flows into the first channel; The opening is an opening arranged at the farthest end of the drainage tube, and / or a side hole of a side wall of the drainage tube; One end of the reinforcement tube connected to the drainage tube is in a bent structure, so as to better position the fixed cannula at the target position.
3. The fixed cannula according to claim 2, characterized in that: The fixed cannula also includes a developing structure, which is arranged on at least one of the drainage tube, the expansion piece, the bending structure, and the reinforcement tube, and is used to indicate the position of the fixed cannula. The developing structure is a continuous film layer that can be developed, or the developing structure includes a plurality of developing marking rings, and the plurality of developing marking rings are arranged at equal intervals.
4. The fixed cannula according to claim 2, characterized in that: Two expansion members and two second channels are provided, and the two expansion members are arranged at intervals on the periphery of one end of the reinforcing tube connected to the drainage tube, and the two expansion members are respectively connected to one second channel.
5. The fixed cannula according to claim 2, characterized in that: The fixed cannula further comprises: A connector connected to the other end of the reinforcement tube away from the drainage tube, and the connector is hollow and communicates with the reinforcement tube; a reducer connecting the reinforcement tube and the connector, and the reducer is hollow and communicates with the reinforcement tube and the connector; The first channel and the second channel are arranged inside the reinforcement tube and / or the reducer tube.
6. The fixed cannula according to claim 5, characterized in that: One end of the second channel away from the expansion element is connected to a one-way valve for controlling the opening and closing of the second channel.
7. The fixed cannula according to claim 1, characterized in that: The tube body is a double-cavity or multi-cavity tube body, the first channel and the second channel are integrally formed with the tube body, and the first channel and the second channel are cavities accommodated in the tube body.
8. The fixed cannula according to claim 1, characterized in that: The first channel is a cavity accommodated in the tube body, and the second channel is an independent tube nested in the tube body and / or outside the tube body.
9. The fixed cannula according to claim 2, characterized in that: The reinforcing tube includes at least a supporting layer, at least a portion of which is a metal wire woven structure, and / or at least a portion of which is a metal wire spirally wound structure; and a first flexible layer arranged on the outside of the supporting layer and / or a second flexible layer arranged on the inside of the supporting layer.
10. The fixed cannula according to claim 3, characterized in that: The drainage tube further includes a third flexible layer disposed outside the developing structure and / or a fourth flexible layer disposed inside the developing structure.