Self-sealing shunt cannula

Abstract

The present invention provides a self-sealing shunt cannula, comprising a cannula and a shunt tube. The cannula comprises a cannula body, a side port connected to the outer wall of the cannula body, and a check valve arranged on the side port, the side port being communicated with the cannula body. The shunt tube comprises a shunt tube body and a shunt joint connected to the shunt tube body, the shunt joint being detachably connected to the side port and / or the check valve. The check valve comprises a valve body and a valve flap which are arranged in the side port, the outer wall of the valve body is sealedly attached to the inner wall of the side port, and a valve body channel is formed in the valve body. When the shunt tube is not connected to the cannula, the valve flap seals the valve body channel so as to prevent blood in the cannula body from flowing out through the side port. When the shunt tube is connected into the cannula, the shunt joint opens the valve flap, and part of blood in the cannula body can flow out of the shunt tube. According to the present invention, collateral circulation can be quickly established to provide protection for lower limbs when lower limb blood supply is insufficient in a circulation support process, the risk of the entry of air during collateral circulation establishment can be effectively avoided, and thrombus formation in the circulation process is reduced.

Description

A self-sealing shunt cannula Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to a self-sealing shunt cannula. Background Art

[0002] During VA-ECMO, the arterial cannula is typically inserted through the femoral artery, occupying the main lumen of the femoral artery. This can lead to insufficient blood supply to the lower limb on the cannulated side, and in severe cases, even necrosis of the lower limb or the need for amputation. This is one of the most important and common complications of ECMO (Extracorporeal Membrane Oxygenation). To prevent insufficient blood flow to the lower limbs, a shunt is typically connected to the arterial line to perfuse and maintain arterial blood supply to the lower limbs.

[0003] Lower limb ischemia is unpredictable, and there are usually two ways to deal with it. One is to reserve an interface in the arterial circuit. In order to avoid blood spurting out when connecting the shunt tube, a three-way valve needs to be connected at the interface; however, during the long-term diversion process, a thrombus will form at the three-way and interface positions; if the thrombus falls off, it may block the patient's artery and cause life-threatening danger. The other is not to connect the three-way valve at the interface, but to suspend circulatory support and connect the shunt tube when the lower limbs need to be perfused. However, this also brings the risk of insufficient circulatory support for the patient, and in order to avoid insufficient perfusion support caused by prolonged circulatory arrest, the surgeon needs to complete the takeover as quickly as possible, which places extremely high demands on the operating team, and may cause air inflow into the arterial line during rapid operation, thereby threatening the patient's life safety.

[0004] Summary of the Invention

[0005] The technical problem to be solved by the embodiments of the present invention is to provide a self-sealing shunt cannula that can quickly establish collateral circulation to provide protection for the lower limbs when insufficient blood supply to the lower limbs occurs during the circulatory support process, and can effectively avoid the risk of air intake when establishing collateral circulation and reduce thrombosis during the circulation process.

[0006] In order to solve the above technical problems, the present invention provides a self-sealing shunt cannula, comprising:

[0007] A cannula comprising a cannula body, a side tube connected to an outer wall of the cannula body, and a one-way valve provided on the side tube, wherein the side tube is connected to the cannula body;

[0008] A shunt pipe, comprising a shunt pipe body and a shunt joint connected to the shunt pipe body, wherein the shunt joint is detachably connected to the side pipe and / or the one-way valve;

[0009] In which, the one-way valve includes a valve body and a valve flap arranged in the side tube, the outer wall of the valve body is sealed and fitted with the inner wall of the side tube, and the valve body has a valve body channel; when the shunt tube is not connected to the cannula, the valve flap seals the valve body channel to prevent the blood in the cannula body from flowing out through the side tube; when the shunt tube is connected to the cannula, the shunt joint pushes open the valve flap, and part of the blood in the cannula body can flow out of the shunt tube.

[0010] Optionally, when the shunt tube is connected to the cannula, the valve flap is completely in the side tube or partially enters the cannula body, and the portion of the valve flap entering the cannula body accounts for no more than 50% of the cross-section of the cannula body.

[0011] Optionally, the valve body channel passes through the front end and the rear end of the valve body, the valve flap is provided at the front end of the valve body or in the valve body channel, and the rear end of the valve body has a convex edge protruding toward the outer wall of the valve body, and the convex edge is located at the end of the side tube;

[0012] The insertion tube further comprises a cap connected to the side tube so as to press the convex edge between the cap and the end surface of the side tube.

[0013] Optionally, the cap has a cap channel, and the cap channel is connected to the valve body channel;

[0014] During the process of connecting the shunt tube to the cannula, the shunt joint sequentially penetrates the cap channel and the valve body channel to push open the valve flap.

[0015] Optionally, the valve flap has a fixed portion and a movable portion, the fixed portion is connected to the valve body, and the movable portion can rotate relative to the fixed portion to close or open the valve body channel;

[0016] The valve flap has a first side and a second side that are arranged opposite to each other, and the first side is close to the cannula body; when the pressure on the first side is greater than the pressure on the second side, the movable portion of the valve flap rotates toward the second side to close the valve body channel.

[0017] Optionally, the one-way valve includes a valve flap, a fixed portion of the valve flap is connected to the inner wall of the valve body or the end of the valve body, and a movable portion of the valve flap is close to the end of the valve body and / or the inner wall of the valve body;

[0018] When the pressure on the first side of the valve flap is greater than the pressure on the second side, the movable portion of the valve flap is sealed against the end of the valve body and / or the inner wall of the valve body; when the shunt tube is connected to the cannula, the movable portion of the valve flap is squeezed by the shunt joint and rotates toward the cannula body.

[0019] Optionally, the fixing portion of the valve flap is located in an upper direction relative to the blood flow direction in the cannula body.

[0020] Optionally, the one-way valve includes two valve flaps, the fixed portions of the two valve flaps are respectively fixed to opposite sides of the end of the valve body, and the movable portions of the two valve flaps are close to each other to form a duckbill shape protruding toward the cannula body;

[0021] When the pressure on the first side of the valve flap is greater than the pressure on the second side, the movable parts of the two valve flaps are tightly attached to each other and sealed with the end of the valve body; when the shunt tube is connected to the insert tube, the movable parts of the two valve flaps are squeezed away from each other by the shunt joint.

[0022] Optionally, the valve body is provided with two intersecting inclined surfaces at one end close to the cannula body, and each inclined surface is provided with a valve flap; the movable portion of each valve flap includes a first movable portion and a second movable portion, the first movable portions of the two valve flaps are close to the inclined surfaces, and the second movable portions of the two valve flaps are close to each other;

[0023] When the pressure on the first side of the valve flap is greater than the pressure on the second side, the first movable portions of the two valve flaps are sealed against the corresponding inclined surfaces, and the second movable portions of the two valve flaps are in close contact with each other.

[0024] Optionally, the fixing portion of any one of the two valve flaps is located in an upper direction relative to the blood flow direction in the cannula body.

[0025] Optionally, the length of the valve body entering the side tube is not less than 1 / 2 of the length of the side tube, and the valve flap is provided on a side of the valve body close to the cannula body;

[0026] The diverter joint is inserted into the one-way valve, and a length of the diverter joint entering the one-way valve is greater than a length of the valve body.

[0027] The implementation of the present invention has the following beneficial effects:

[0028] The present invention provides a one-way valve on the side tube of the cannula. The outer wall of the one-way valve seals against the inner wall of the side tube, and the valve flap of the one-way valve is connected to the valve body. When the shunt tube is not connected to the cannula, the valve flap can seal the valve body channel to prevent blood in the cannula body from flowing out of the side tube. When the shunt tube is connected to the cannula, the shunt connector of the shunt tube pushes open the valve flap, allowing some blood in the cannula body to flow out through the shunt tube. Because the valve body and valve flap enter the side tube and occupy the side tube space, when the valve flap is closed, the space between the side tube and the cannula body is reduced, reducing the volume of the blood flow dead space in the cannula when the shunt tube is not connected, thereby reducing the risk of thrombosis. When the cannula is used to transport blood and is not connected to the shunt tube, the valve flap automatically seals the valve body channel due to the pressure difference between the inside and outside of the cannula. When the shunt tube needs to be connected, the valve flap is pushed open by the shunt connector to open the valve body channel, without suspending ECMO circulatory support. Moreover, this connection method is simple and quick to operate and can reduce or prevent gas from entering the cannula. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] FIG1 is a schematic structural diagram of a self-sealing shunt cannula provided in an embodiment of the present invention;

[0030] FIG2 is a cross-sectional view of a self-sealing shunt cannula provided in an embodiment of the present invention;

[0031] FIG3 is a schematic structural diagram of a one-way valve provided in an embodiment of the present invention;

[0032] FIG4 is a cross-sectional view of the one-way valve in FIG3 ;

[0033] FIG5 is a schematic diagram of a partial structure of a cannula including the one-way valve shown in FIG3 ;

[0034] FIG6 is a schematic diagram of a partial structure of a self-sealing shunt cannula including the one-way valve shown in FIG3 ;

[0035] FIG7 is a schematic structural diagram of another one-way valve provided in an embodiment of the present invention;

[0036] FIG8 is a cross-sectional view of the one-way valve in FIG7;

[0037] FIG9 is a schematic diagram of a partial structure of the cannula including the one-way valve shown in FIG7 ;

[0038] FIG10 is a schematic diagram of a partial structure of a self-sealing shunt cannula including the one-way valve shown in FIG7 .

[0039] In the figure: 100 cannula, 101 cannula body, 102 perfusion hole, 103 side tube, 104 one-way valve, 105 valve body, 106 valve body channel, 107 valve disc, 108 convex edge, 109 cap, 110 cap channel, 111 fixed part, 112 movable part, 113 inclined surface, 114 first movable part, 115 second movable part, 200 shunt pipe, 201 shunt pipe body, 202 shunt joint. DETAILED DESCRIPTION

[0040] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0041] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0043] This embodiment provides a self-sealing shunt cannula, comprising a cannula 100 and a shunt tube 200 detachably connected to the cannula 100. The cannula 100 comprises a cannula body 101, a side tube 103 connected to the outer wall of the cannula body 101, and a one-way valve 104 disposed on the side tube 103. The side tube 103 is in communication with the cannula body 101. The shunt tube 200 comprises the shunt body 201 and a shunt connector 202 connected to the shunt body 201. The shunt connector 202 is detachably connected to the side tube 103 and / or the one-way valve 104. In which, the one-way valve 104 includes a valve body 105 and a valve flap 107 arranged in the side tube 103, the outer wall of the valve body 105 is sealed and fitted with the inner wall of the side tube 103, and the valve body 105 has a valve body channel 106; when the shunt tube 200 is not connected to the cannula 100, the valve flap 107 seals the valve body channel 106 to prevent the blood in the cannula body 101 from flowing out through the side tube 103; when the shunt tube 200 is connected to the cannula 100, the shunt joint 202 pushes open the valve flap 107, and part of the blood in the cannula body 101 can flow out of the shunt tube 200. As shown in Figures 1 and 2, the side tube 103 is detachably provided at the proximal end of the cannula body 101, and a perfusion hole 102 is provided at the distal end of the cannula body 101. The oxygen-rich blood after ECMO oxygenation treatment is returned to the human body through the cannula 100, and the perfusion hole 102 guides the oxygen-rich blood to a designated position. After the shunt tube 200 is connected to the cannula 100, part of the blood in the cannula body 101 can flow out through the shunt tube 200 to perfuse other parts of the human body. For example, the shunt tube 200 can be used to guide blood to the lower limbs for perfusion to ensure the arterial blood supply of the lower limbs.

[0044] Because the valve body 105 and valve flap 107 enter the side tube 103 and occupy the space in the side tube 103, when the valve flap 107 is closed, the space between the side tube 103 and the main body of the cannula 100 is reduced, reducing the volume of the blood flow dead space within the cannula 100 when the shunt tube 200 is not connected, thereby reducing the risk of thrombosis. It is worth noting that the closer the valve flap 107 is to the inner wall of the cannula 100 body, the smaller the dead space volume. However, if the valve flap 107 is flush with the inner wall of the cannula 100 body or even extends into the cannula 100 body, the portion of the valve flap 107 that enters the cannula 100 body when it is pushed open by the shunt connector 202 will increase, which may cause the flow surface of the cannula 100 body to shrink sharply, affecting normal blood flow.

[0045] In order to reduce the dead space of the cannula 100 while taking into account the flow capacity of the cannula 100, this embodiment limits the position of the valve flap 107. Specifically, the length of the valve body 105 entering the side tube 103 is not less than 1 / 2 of the length of the side tube 103. During the process of the shunt tube 200 being connected to the cannula 100, the shunt joint 202 enters the valve body 105 to squeeze the valve flap 107, so that the valve flap 107 approaches the cannula body 101. After the shunt tube 200 is connected to the cannula 100, the valve flap 107 is completely in the side tube 103 or the valve flap 107 partially enters the cannula body 101. When the valve flap 107 is completely in the side tube 103, the connection of the shunt tube 200 will not affect the original flow area of ​​the cannula body 101, and blood can flow smoothly in the cannula body 101. In the case where the valve flap 107 partially enters the cannula body 101, the portion of the valve flap 107 that enters the cannula body 101 will overlap with the cross-sectional area of ​​the cannula body 101, and the overlapping portion will hinder the blood flow. In this embodiment, the portion of the valve flap 107 that enters the cannula body 101 accounts for no more than 50% of the cross-sectional area of ​​the cannula body 101, so as to reduce the obstruction of the valve flap 107 on the blood flow in the cannula body 101 and provide a sufficiently large flow surface for the passage of blood.

[0046] Referring to Figures 4 and 5 , the valve body passage 106 extends through the front and rear ends of the valve body 105. The valve flap 107 is disposed at the front end of the valve body 105 or within the valve body passage 106. The rear end of the valve body 105 has a flange 108 protruding toward the outer wall of the valve body 105. The flange 108 is located at the end of the side tube 103. The cannula 100 also includes a cap 109, which is connected to the side tube 103 to compress the flange 108 between the cap 109 and the end surface of the side tube 103. The one-way valve 104 is made of silicone. The outer wall of the valve body 105 is interference-fitted with the inner wall of the side tube 103. The flange 108 is located at the external end of the side tube 103. The valve flap 107 is positioned near the cannula body 101. The cap 109 is interference-fitted or thread-fitted with the side tube 103 , thereby fixing the convex edge 108 of the one-way valve 104 and preventing the one-way valve 104 from being separated from the side tube 103 .

[0047] In one possible implementation, the cap 109 may have a closed end surface to better protect the one-way valve 104. In this structure, when connecting the shunt tube 200, the cap 109 must first be removed from the side tube 103. In another possible implementation, the cap 109 has a cap channel 110 that is connected to the valve body channel 106. During the process of connecting the shunt tube 200 to the cannula 100, the shunt connector 202 sequentially penetrates the cap channel 110 and the valve body channel 106 before pushing open the valve disc 107. This structure can reduce the number of steps required to install the shunt tube 200 and improve the efficiency of connecting the shunt tube 200 to the cannula 100.

[0048] The valve flap 107 has a fixed portion 111 and a movable portion 112. The fixed portion 111 is connected to the valve body 105, and the movable portion 112 can rotate relative to the fixed portion 111 to close or open the valve body channel 106. The valve flap 107 has a first side and a second side that are arranged opposite to each other. The first side is close to the cannula body 101. When the pressure on the first side is greater than the pressure on the second side, the movable portion 112 of the valve flap 107 rotates toward the second side to close the valve body channel 106. Specifically, when blood flows in the cannula body 101, the pressure on the first side of the valve flap 107 is greater than the pressure on the second side. The pressure difference will drive the valve flap 107 to automatically close the valve body channel 106, and the blood in the cannula body 101 cannot flow out through the valve body channel 106.

[0049] In one possible implementation, referring to Figures 3-6 , the one-way valve 104 includes a valve flap 107. A fixed portion 111 of the valve flap 107 is connected to the inner wall of the valve body 105 or the end of the valve body 105, and a movable portion 112 of the valve flap 107 is in close contact with the end of the valve body 105 and / or the inner wall of the valve body 105. When the pressure on a first side of the valve flap 107 is greater than the pressure on a second side, the movable portion 112 of the valve flap 107 seals against the end of the valve body 105 and / or the inner wall of the valve body 105. When the shunt tube 200 is connected to the cannula 100, the movable portion 112 of the valve flap 107 is squeezed by the shunt connector 202 and rotates toward the cannula body 101. When the shunt tube 200 is not connected to the cannula 100, the movable portion 112 of the valve flap 107 should not be positioned above the blood flow direction in the cannula body 101 to prevent the blood in the cannula body 101 from first impacting the movable portion 112 of the valve flap 107 and causing the movable portion 112 of the valve flap 107 to rotate toward the cannula body 101. Specifically, as shown in FIG5 , the fixed portion 111 of the valve flap 107 can be positioned above the blood flow direction in the cannula body 101. In this way, the blood will first impact the fixed portion 111 of the valve flap 107, thereby driving the movable portion 112 of the valve flap 107 to rotate away from the cannula body 101, thereby sealing the valve body passage 106.

[0050] In another possible implementation, the one-way valve 104 includes two valve flaps 107. The fixed portions 111 of the two valve flaps 107 are fixed to opposite ends of the valve body 105. The movable portions 112 of the two valve flaps 107 are positioned close to each other, forming a duckbill shape that protrudes toward the cannula body 101. When the pressure on a first side of the valve flaps 107 is greater than the pressure on a second side, the movable portions 112 of the two valve flaps 107 abut against each other and seal against the end of the valve body 105. When the shunt tube 200 is connected to the cannula 100, the movable portions 112 of the two valve flaps 107 are squeezed away from each other by the shunt connector 202. Specifically, referring to Figures 7-10 , the valve body 105 is provided with two intersecting inclined surfaces 113 at one end near the cannula body 101. Each inclined surface 113 is provided with a valve flap 107. The movable portion 112 of each valve flap 107 includes a first movable portion 114 and a second movable portion 115. The first movable portions 114 of both valve flaps 107 are in close proximity to the inclined surfaces 113, and the second movable portions 115 of the two valve flaps 107 are close to each other. When the pressure on the first side of the valve flap 107 is greater than the pressure on the second side, the first movable portions 114 of the two valve flaps 107 seal against the corresponding inclined surfaces 113, and the second movable portions 115 of the two valve flaps 107 cling to each other. Similarly, when the shunt tube 200 is not connected to the cannula 100, to prevent blood within the cannula body 101 from first impacting the second movable portions 115 of the two valve flaps 107, causing the valve flaps 107 to fail to seal the valve body passage 106, the second movable portions 115 of the valve flaps 107 should not be aligned parallel to the blood flow direction. Specifically, the fixed portion 111 of either valve flap 107 can be positioned above the blood flow direction within the cannula body 101. This way, blood will first impact the fixed portion 111 of the valve flap 107, driving the movable portions 112 of the valve flaps 107 closer together, sealing the valve body passage 106.

[0051] The shunt connector 202 is interference-fitted or threadedly fitted with the cannula 100. The front end of the shunt connector 202 is inserted into the one-way valve 104. To ensure that the shunt connector 202 can smoothly push open the valve disc 107 during the process of connecting the shunt tube 200 to the cannula 100, the length of the shunt connector 202 entering the one-way valve 104 is greater than the length of the valve body 105, as shown in Figures 6 and 10.

[0052] The present disclosure provides a one-way valve 104 on the side tube 103 of the cannula 100. The outer wall of the valve body 105 of the one-way valve 104 is sealed and fitted with the inner wall of the side tube 103. The valve flap 107 of the one-way valve 104 is connected to the valve body 105. When the shunt tube 200 is not connected to the cannula 100, the valve flap 107 can seal the valve body channel 106 to prevent the blood in the cannula body 101 from flowing out of the side tube 103. When the shunt tube 200 is connected to the cannula 100, the shunt connector 202 of the shunt tube 200 pushes open the valve flap 107, so that part of the blood in the cannula body 101 can flow out through the shunt tube 200. Since the valve body 105 and the valve flap 107 enter the side tube 103 and occupy the space of the side tube 103, when the valve flap 107 is closed, the space between the side tube 103 and the main body of the cannula 100 is reduced, and the volume of the blood flow dead space in the cannula 100 when the shunt tube 200 is not connected is reduced, thereby reducing the risk of thrombosis. When the cannula 100 is used to transport blood and is not connected to the shunt tube 200, the valve flap 107 is affected by the pressure difference between the inside and outside of the cannula 100 and automatically seals the valve body channel 106. When insufficient blood supply to the lower limbs occurs during the circulatory support process, the shunt tube 200 needs to be connected, and the valve flap 107 is pushed open by the shunt connector 202 to open the valve body channel 106. There is no need to suspend ECMO circulatory support. This connection method is simple and quick to operate, can quickly establish collateral circulation to provide protection for the lower limbs, and can effectively avoid the risk of air intake when establishing collateral circulation, and can also reduce thrombosis during the circulation process.

[0053] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0054] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A self-sealing shunt cannula, characterized in that: include: The cannula (100) comprises a cannula body (101), a side tube (103) connected to the outer wall of the cannula body (101), and a one-way valve (104) provided on the side tube (103), wherein the side tube (103) is connected to the cannula body (101); A shunt pipe (200), comprising a shunt pipe body (201) and a shunt joint (202) connected to the shunt pipe body (201), wherein the shunt joint (202) is detachably connected to the side pipe (103) and / or the one-way valve (104); The one-way valve (104) comprises a valve body (105) and a valve flap (107) arranged in the side tube (103); the outer wall of the valve body (105) is sealed and fitted with the inner wall of the side tube (103); and the valve body channel (106) is provided in the valve body (105); when the shunt tube (200) is not connected to the cannula (100), the valve flap (107) seals the valve body channel (106) to prevent the blood in the cannula body (101) from flowing out through the side tube (103); when the shunt tube (200) is connected to the cannula (100), the shunt joint (202) pushes open the valve flap (107), and part of the blood in the cannula body (101) can flow out from the shunt tube (200).

2. The self-sealing shunt cannula according to claim 1, characterized in that: When the shunt tube (200) is connected to the cannula (100), the valve flap (107) is completely located in the side tube (103) or partially enters the cannula body (101), and the portion of the valve flap (107) entering the cannula body (101) accounts for no more than 50% of the cross-section of the cannula body (101).

3. The self-sealing shunt cannula according to claim 1, characterized in that: The valve body channel (106) passes through the front end and the rear end of the valve body (105); the valve flap (107) is arranged at the front end of the valve body (105) or in the valve body channel (106); The rear end has a convex edge (108) protruding toward the outer wall of the valve body (105), and the convex edge (108) is located at the end of the side tube (103); The insertion tube (100) further comprises a cap (109), wherein the cap (109) is connected to the side tube (103) so as to press the flange (108) between the cap (109) and the end surface of the side tube (103).

4. The self-sealing shunt cannula according to claim 3, characterized in that: The cap (109) has a cap channel (110), and the cap channel (110) is connected to the valve body channel (106); During the process of connecting the shunt tube (200) to the insertion tube (100), the shunt joint (202) sequentially penetrates the cap channel (110) and the valve body channel (106) and then pushes open the valve flap (107).

5. The self-sealing shunt cannula according to claim 1, characterized in that: The valve flap (107) comprises a fixed portion (111) and a movable portion (112), wherein the fixed portion (111) is connected to the valve body (105), and the movable portion (112) can rotate relative to the fixed portion (111) to close or open the valve body channel (106); The valve flap (107) has a first side and a second side that are arranged opposite to each other, and the first side is close to the cannula body (101); when the pressure on the first side is greater than the pressure on the second side, the movable portion (112) of the valve flap (107) rotates toward the second side to close the valve body channel (106).

6. The self-sealing shunt cannula according to claim 5, characterized in that: The one-way valve (104) comprises a valve flap (107), a fixed portion (111) of the valve flap (107) being connected to an inner wall of the valve body (105) or an end of the valve body (105), and a movable portion (112) of the valve flap (107) being close to the end of the valve body (105) and / or the inner wall of the valve body (105); When the pressure on the first side of the valve flap (107) is greater than the pressure on the second side, the movable portion (112) of the valve flap (107) is in sealing contact with the end of the valve body (105) and / or the inner wall of the valve body (105); When the shunt tube (200) is connected to the cannula (100), the movable portion (112) of the valve flap (107) is squeezed by the shunt joint (202) and rotates toward the cannula body (101).

7. The self-sealing shunt cannula according to claim 6, characterized in that: The fixing portion (111) of the valve flap (107) is located in the upper direction of the blood flow in the cannula body (101).

8. The self-sealing shunt cannula according to claim 5, characterized in that: The one-way valve (104) comprises two valve flaps (107), the fixed parts (111) of the two valve flaps (107) are respectively fixed to two opposite sides of the end of the valve body (105), and the movable parts (112) of the two valve flaps (107) are close to each other to form a duckbill shape protruding toward the cannula body (101); When the pressure on the first side of the valve flap (107) is greater than the pressure on the second side, the movable parts (112) of the two valve flaps (107) are tightly attached to each other and are sealed against the end of the valve body (105); when the shunt tube (200) is connected to the insertion tube (100), the movable parts (112) of the two valve flaps (107) are squeezed by the shunt joint (202) and move away from each other.

9. The self-sealing shunt cannula according to claim 8, characterized in that The valve body (105) is provided with two intersecting inclined surfaces (113) at one end close to the cannula body (101), and each of the inclined surfaces (113) is provided with a valve flap (107); the movable portion (112) of each valve flap (107) comprises a first movable portion (114) and a second movable portion (115), and the first movable portions (114) of the two valve flaps (107) are close to the inclined surfaces (113), and the second movable portions (115) of the two valve flaps (107) are close to each other; When the pressure on the first side of the valve flap (107) is greater than the pressure on the second side, the first movable portions (114) of the two valve flaps (107) are sealed against the corresponding inclined surfaces (113), and the second movable portions (115) of the two valve flaps (107) are in close contact with each other.

10. The self-sealing shunt cannula according to claim 8, characterized in that: The fixing portion (111) of any one of the two valve flaps (107) is located in the upper direction of the blood flow in the cannula body (101).

11. The self-sealing shunt cannula according to claim 1, characterized in that: The length of the valve body (105) entering the side tube (103) is not less than 1 / 2 of the length of the side tube (103), and the valve flap (107) is arranged on a side of the valve body (105) close to the cannula body (101); The diverter joint (202) is inserted into the one-way valve (104), and the length of the diverter joint (202) entering the one-way valve (104) is greater than the length of the valve body (105).

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