VA-ECMO femoral artery cannula for lower limb blood perfusion and indwelling catheter method

Abstract

The invention relates to the technical field of medical instruments, in particular to a VA-ECMO femoral artery cannula for lower limb blood perfusion and a catheter indwelling method.The technical scheme includes that the front end of the cannula is guided into the femoral artery through a puncture guide core; an output hole is formed in the front end of the cannula in a communicating mode, and the area, provided with the output hole, of the front end of the cannula is divided into an area A; the joint piece is communicated with the rear end of the cannula; the aorta counterpulsation balloon is arranged at the middle end of the outer surface of the cannula, and the front end is close to the A area; the bulge air bag is arranged on the portion, at the rear end of the aorta counterpulsation balloon, of the cannula, the end, facing the aorta counterpulsation balloon, of the bulge air bag is matched with the wall of the cannula to form an obtuse angle, and the end, away from the aorta counterpulsation balloon, of the bulge air bag is matched with the wall of the cannula to form an acute angle; the air bag opening is formed in the portion, far away from one side of the aorta counterpulsation balloon, of the swell air bag, and is used for inflating the aorta counterpulsation balloon and the swell air bag; and the side holes are formed in the intubation tube at the front end of the bulge air bag and the middle of the rear end of the aorta counterpulsation balloon.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a VA-ECMO femoral artery cannula for lower limb blood perfusion and a cannulation method. Background Art

[0002] Extracorporeal membrane oxygenation (ECMO) is a short-term life support technology widely used in the rescue of patients with acute cardiopulmonary failure. The veno-arterial (VA-ECMO) mode is mainly used in cardiogenic shock, cardiac arrest and severe heart failure. VA-ECMO inserts arteriovenous cannula to drain the patient's central venous blood to the extracorporeal oxygenator for gas exchange, and the oxygenated oxygen-rich blood is pumped back into the arterial system by a centrifugal pump to maintain systemic circulation perfusion. In clinical practice, femoral artery cannulation is the most commonly used arterial return route for VA-ECMO because of its convenient operation, small puncture trauma, and rapid establishment of extracorporeal circulation. However, traditional femoral artery cannulation technology may lead to insufficient perfusion of the lower limbs, causing ischemic complications such as distal limb ischemia and necrosis, and even affecting the patient's prognosis.

[0003] Because the ECMO device returns blood to the femoral artery, it causes high-flow, high-pressure reverse blood flow in the common femoral artery, which may inhibit the left heart's own ejection of blood and further increase the burden on the heart; in addition, femoral artery catheterization may hinder distal lower limb blood flow, increasing the risk of arterial thrombosis, limb ischemia and nerve damage.

[0004] In view of the above, the existing publication number CN112915294A proposes a solution. In actual clinical application, it is found that due to changes in local hemodynamics, certain vascular turning points are susceptible to turbulence, thereby increasing the risk of thrombosis; for example, the setting of the arc-shaped protrusion of the bulge airbag causes the distance between the bulge airbag and the blood vessel to fluctuate greatly when the blood circulates, thereby aggravating the blockage of local blood flow and further reducing the smoothness of blood flow; in addition, after the air ring airbag is inflated and blocked, the blood flow on both sides may be completely isolated; for this reason, the present application proposes a VA-ECMO femoral artery cannulation and catheterization method for lower limb blood perfusion to solve the above problems. Summary of the invention

[0005] In view of the above situation, the present invention provides a VA-ECMO femoral artery cannulation and catheterization method for lower limb blood perfusion. The device uses an aortic counterpulsation balloon to continuously and repeatedly expand the blood vessels, thereby alleviating the insufficient perfusion of the lower limbs caused by arterial vasoconstriction and generating pulsatile blood flow.

[0006] A VA-ECMO femoral artery cannula for lower limb blood perfusion, comprising:

[0007] The cannula has its front end guided into the femoral artery through a puncture guide wire. An output hole is communicatively provided at the front end of the cannula, and the area of the front end of the cannula where the output hole is provided is defined as Area A.

[0008] The connector is communicatively provided at the rear end of the cannula.

[0009] The aortic counterpulsation balloon is provided in the middle of the outer surface of the cannula, and its front end is close to Area A.

[0010] The bulging balloon is provided on the cannula at the rear of the aortic counterpulsation balloon. One end of the bulging balloon facing the aortic counterpulsation balloon cooperates with the cannula wall at an obtuse angle, and the end away from the aortic counterpulsation balloon cooperates with the cannula wall at an acute angle.

[0011] The balloon port is provided on the cannula on the side of the bulging balloon away from the aortic counterpulsation balloon and is used for inflating the aortic counterpulsation balloon and the bulging balloon.

[0012] The side hole is provided on the cannula at the middle of the front end of the bulging balloon and the rear end of the aortic counterpulsation balloon. The distance between the outlet end of the side hole and the bulging balloon and the opposite blood vessel wall tends to be gentle.

[0013] Preferably, there are multiple output holes, which are annularly distributed in Area A.

[0014] Preferably, an annular guide wire is provided on the surface of the cannula in Area A and in the middle of the aortic counterpulsation balloon.

[0015] Preferably, there are two balloon ports, and the two balloon ports are symmetrically arranged on the cannula and are communicatively provided with the aortic counterpulsation balloon and the bulging balloon respectively.

[0016] Preferably, the front end diameter of the cannula is smaller than the rear end diameter.

[0017] Preferably, the connector includes a plastic connector and an injection port.

[0018] The plastic connector is communicatively provided at one end of the cannula.

[0019] The injection port is communicatively provided on the plastic connector.

[0020] A catheterization method for the VA-ECMO femoral artery cannula for lower limb blood perfusion as described above:

[0021] First, under the guidance of the puncture guide wire, the front end of the cannula is directed towards the proximal end of the femoral artery; the bulging balloon and the aortic counterpulsation balloon are placed inside the femoral artery, and the side hole is controlled to face the distal end of the femoral artery, and perfusion is carried out into the cannula through the connector.

[0022] Then, air is respectively inflated into the bulging balloon and the aortic counterpulsation balloon through two balloon ports. After inflation, the bulging balloon can be used for positioning the intubation to prevent the intubation from falling off. The side of the inflated bulging balloon facing the aortic counterpulsation balloon forms an obtuse angle with the intubation wall, thereby narrowing the width of the blood flow channel between the side hole outlet and the bulging balloon and reducing the formation of turbulence. At the same time, the side of the bulging balloon away from the aortic counterpulsation balloon forms an acute angle with the intubation, and is clamped at the acute angle with the position of the blood vessel intubation. After clamping, the surface of the bulging balloon forms an obtuse contact area with the blood vessel wall, reducing the occurrence of turbulence on the side of the bulging balloon away from the aortic counterpulsation balloon and improving the fixing stability of the intubation.

[0023] Then, the aortic counterpulsation balloon is inflated to inflate and deflate synchronously with the patient's heart rate. During the inflation process, the blood flow on both sides of the aortic counterpulsation balloon is blocked, and at the same time, the arterial blood vessels are dilated and contracted. During the deflation process, the blood in the artery flows again and is not blocked by the aortic counterpulsation balloon, forming a pulsatile blood flow. The beneficial effects of the above technical solutions are as follows:

[0024] (1) Through the setting of the aortic counterpulsation balloon, the inflation is synchronized with the patient's heart rate. During inflation, the blood flow is blocked and the blood vessels are dilated, and during deflation, the blood flow is restored, forming a pulsatile blood flow.

[0025] (2) Through the setting of the obtuse angle and acute angle of the bulging balloon, accidental movement or falling off of the intubation in the blood vessel is avoided, and the stability of the placement is improved. Its special angles after inflation (forming an obtuse angle and an acute angle with the intubation wall) optimize the fit with the blood vessel wall, reduce turbulence and further enhance the fixing effect. Description of the Drawings

[0026] Figure 1 is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 is a schematic diagram of the single-chamber structure of the intubation of the present invention;

[0028] Figure 3 is a schematic diagram of the double-chamber of the intubation of the present invention;

[0029] Figure 4 is a schematic diagram of the structure of the inflation balloon of the present invention.

[0030] In the figure: 1. Intubation; 101. Area A; 2. Puncture guide wire; 3. Output hole; 4. Connector; 41. Material connector; 42. Liquid injection port; 5. Aortic counterpulsation balloon; 6. Bulging balloon; 7. Balloon port; 8. Side hole; 9. Annular guide wire; 10. Inflation balloon. Detailed Embodiments

[0031] Regarding the foregoing and other technical contents, features and effects of the present invention, in the following with reference to the attached Figures 1 to 4In the detailed description of the embodiments, it can be clearly presented that the structural contents mentioned in the following embodiments are all referenced to the accompanying drawings of the specification.

[0032] Reference can be made to Figure 1 , the present application proposes a VA-ECMO femoral artery cannulation and catheterization method for lower limb blood perfusion, which is specifically as follows:

[0033] Reference can be made to Figure 1 , the present application is mainly composed of a cannula 1, a puncture guide wire 2 for guiding the cannula 1 into the femoral artery, an output hole 3 provided at the front end of the cannula 1, a connector 4 communicatively provided at the rear end of the cannula 1, a bulge balloon 6 and an aortic counterpulsation balloon 5 provided on the cannula 1, an airbag port 7 for inflation, and a side hole 8 provided on the cannula 1. Through the mutual cooperation between these structures, the VA-ECMO femoral artery cannulation work for lower limb blood perfusion is realized, which reduces the formation of thrombus during work and forms a pulsatile blood flow.

[0034] Reference can be made to Figure 1 , the diameter of the front end of the cannula 1 is smaller than that of the rear end, and the diameter of the rear end gradually increases to form a large connection port, which is more convenient for connecting with the connector 4. Through the connector 4, blood can be input into the cannula 1 for work; an output hole 3 is provided in the front end area of the cannula 1, and a side hole 8 is provided on the cannula 1 at the middle part between the front end of the bulge balloon 6 and the rear end of the aortic counterpulsation balloon 5. When blood enters the output hole 3, it is injected outwards through the output hole 3 and the side hole 8.

[0035] It should be noted that the diameter of the cannula 1 between the output hole 3 and the bulge balloon 6 is the same, which is the front end diameter; starting from the end of the bulge balloon 6 far away from the aortic counterpulsation balloon 5, the diameter gradually increases, and this position is the rear end diameter. The rear end diameter only needs to be sized to fit the connector 4 to be connected; the front end diameter is adapted to be inserted into the femoral artery, and the rear end diameter is not specifically limited and can be adjusted based on different existing models of the connector 4.

[0036] Among them, it should be noted that the area where the output hole 3 is provided on the cannula 1 is divided into area A 101, and a plurality of output holes 3 are annularly distributed in the area A 101;

[0037] Furthermore, the connector 4 includes a plastic connector 41 and a liquid injection port 42. The plastic connector 41 is communicatively provided at one end of the cannula 1, and the liquid injection port 42 is communicatively provided on the plastic connector 41; through the connection with the outside through the liquid injection port 42, it enters the plastic connector 41 and is guided into the cannula 1.

[0038] Reference can be made to Figures 1 - 2, in one embodiment, there is only one inner cavity in the intubation tube 1, and both the side hole 8 and the output hole 3 communicate with this inner cavity; when blood enters the inner cavity of the intubation tube 1 through the connector 4, the blood can be shunted and enter the femoral artery from the side hole 8 and the output hole 3.

[0039] Reference can be made to Figure 1 and Figure 3 , in another embodiment, there are two inner cavities in the intubation tube 1. The two inner cavities communicate with the side hole 8 and the output hole 3 respectively. Two liquid injection ports 42 need to be provided correspondingly on the connected connector 4, and the two liquid injection ports 42 are separately communicated with the two inner cavities. When blood enters the inner cavity of the intubation tube 1 through the connector 4, it has been shunted and enters the two inner cavities respectively, and then enters the femoral artery from the holes (side hole 8 and output hole 3) corresponding to the two inner cavities.

[0040] In view of the above two embodiments, the first embodiment is the optimal one, which has fewer connecting components and is more convenient to operate; while in the second embodiment, the situation where the two holes output outward can be controlled separately, so different implementation methods can be selected in different scenarios.

[0041] Reference can be made to Figures 1 - 3 , the aortic counterpulsation balloon 5 is located in the middle of the outer surface of the intubation tube 1, its front end is close to the A area 101, and an annular guide wire 9 is arranged between the front end of the aortic counterpulsation balloon 5 and the middle of the A area 101. The annular guide wire 9 can increase the toughness of the puncture tube and help with puncture; it should be noted that the aortic counterpulsation balloon 5 is connected to an external console, and the console transports and recovers gas through a pneumatic system to achieve inflation / deflation. This is the movement principle of a relatively mature existing mechanical circulatory assist device, and this application will not elaborate further.

[0042] Through the setting of the aortic counterpulsation balloon 5, the pulse inflation is synchronized with the patient's heart rate for inflation and deflation. When the patient's pulse beats, air is pumped in, and when the patient's pulse stops, it deflates. Thus, the blood vessels are repeatedly dilated to form a pulsatile blood flow; it helps to restore blood vessel elasticity, improve blood supply, promote collateral circulation, prevent restenosis, and reduce thrombus formation.

[0043] Reference can be made to Figures 1 - 3 , the bulging balloon 6 is used to position the intubation tube 1 to prevent the intubation tube 1 from slipping out of the femoral artery during operation; the bulging balloon 6 is specifically arranged on the intubation tube 1 at the rear end of the aortic counterpulsation balloon 5. There is a side hole 8 between the bulging balloon 6 and the middle of the aortic counterpulsation balloon 5. When blood is injected into the blood vessel through the side hole 8, the pressure at the outlet end of the side hole 8 is relatively large, and turbulence is likely to occur, so thrombus accumulation is likely to occur here; to further improve this problem, the shape of the bulging balloon 6 is further improved. The end of the bulging balloon 6 facing the aortic counterpulsation balloon 5 is matched with the wall of the intubation tube 1 to form an obtuse angle, and the end away from the aortic counterpulsation balloon 5 is matched with the wall of the intubation tube 1 to form an acute angle;

[0044] With its obtuse - angled design, when the injected blood flows out from the side hole 8, the distance from the outflow position to the position of the bulging airbag 6 to the femoral artery facing the front side becomes gentle, so the blood flow rate is relatively stable; by optimizing the design of the bulging airbag (6), it is avoided that the airbag in the prior art is too large, resulting in a reduction in the distance from the opposite blood vessel wall; thus, the occurrence of an irregular flow path can be effectively reduced, achieving the effect of reducing the occurrence of turbulence.

[0045] The acute - angle setting at the other end forms an obtuse - angle contact area between one side surface of the bulging airbag 6 and the blood vessel wall, promoting the blood flow process in the blood vessel to maintain a gentle flow - velocity gradient, effectively reducing the drastic change in flow velocity, and reducing the risk of turbulence occurrence; secondly, the acute - angle can better form a clamping connection with the femoral artery, making the connection clamping effect more stable and less likely to have the risk of sliding outwards.

[0046] For reference Figure 1 , the bulging airbag 6 and the intra - aortic balloon pump 5 complete the inflation and deflation work through the balloon ports 7; there are two balloon ports 7, which are independently connected to the bulging airbag 6 and the intra - aortic balloon pump 5 respectively, ensuring independent inflation and deflation operations and improving the control accuracy; to improve the operation convenience, the positions of the two balloon ports 7 are optimized; the balloon port 7 connected to the bulging airbag 6 is arranged on the side away from the intra - aortic balloon pump 5 and is located on the cannula 1, horizontally arranged with the bulging airbag 6, which is convenient for operation and identification; the balloon port 7 connected to the intra - aortic balloon pump 5 is arranged directly in front of the balloon port 7 connected to the bulging airbag 6, making the two balloon ports 7 symmetrically distributed;

[0047] In practical applications, by observing the position of the balloon port 7 connected to the intra - aortic balloon pump 5, the position of the balloon port 7 connected to the symmetric - side bulging airbag 6 can be inferred, so as to quickly locate the bulging airbag 6, which is convenient for adjusting the cannula 1 and operating the device.

[0048] For reference Figure 4 , in the prior art, most inflatable airbags 10 adopt an arc - shaped convex design. To ensure its clamping function, its diameter is usually made larger than or equal to the inner diameter of the blood vessel lumen, thereby enhancing the fixing effect and reducing the risk of the cannula 1 slipping out; however, under this design, four points: P1, P2, P3, and P4 are formed between the side hole 8 and the inflatable airbag 10. The four points represent the change in the distance between the side hole 8 and the inflatable airbag 10 and the inner wall of the blood vessel, corresponding to the change in the distance between the starting position of the side - hole 8 outlet and the acute - angle of the bulging airbag 6 and the blood vessel wall in this application.

[0049] For reference Figure 4, there will be obvious spacing changes between P1, P2 and P3, resulting in uneven blood flow when injecting blood into the femoral artery, and further increasing the probability of the formation of turbulence; while for the obtuse angle setting of the present application, the spacing change between the outlet of the side hole 8 and the acute angle of the bulge balloon 6 with the blood vessel wall tends to be gentle, avoiding the drastic fluctuation of the blood flow velocity in the blood vessel at this position, thereby reducing the formation of turbulence; secondly, when flowing to P4, the setting shape between the inflation balloon 10 and the cannula 1 forms an obvious angle with the blood vessel wall after being inserted into the blood vessel, and the blood flow is prone to induce turbulence when flowing through this area (P4), affecting the stability of the overall blood flow; in the present application, the surface of the side of the bulge balloon 6 connected to the cannula 1 at an obtuse angle is set in a straight line and has almost no significant fluctuations or irregular undulations. After the bulge balloon 6 is placed in the blood vessel, it forms an obtuse angle contact area with the blood vessel wall far from the aortic counterpulsation balloon 5 of the bulge balloon 6; this setting helps to maintain a gentle flow velocity gradient in this area (relative to Figure 4 the position of P1-P3 in Figure 4 ), effectively slowing down the local fluid disturbance at the distal end of the bulge balloon 6 (relative to

[0050] the position of P4 in

[0051] ), reducing the formation of turbulence, and further improving blood flow patency.

[0052] After the cannula 1 successfully enters the blood vessel, it is necessary to ensure that both the bulge balloon 6 and the aortic counterpulsation balloon 5 are inside the femoral artery, and adjust the orientation of the side hole 8 to point it towards the distal end of the femoral artery; at this time, perfusion is carried out into the cannula 1 through the connector 4 to ensure the stability of the fluid environment in the lumen, and at the same time check the patency of the cannula 1.

[0053] Next, the bulge balloon 6 and the aortic counterpulsation balloon 5 are inflated respectively through the two balloon ports 7 to make them expand to the working state; the inflated bulge balloon 6 can effectively play a role in positioning the cannula 1 to prevent it from falling off due to blood flow impact or external operation; the side of the inflated bulge balloon 6 facing the aortic counterpulsation balloon 5 forms an obtuse angle with the tube wall of the cannula 1. This structural design helps to reduce the width difference of the blood flow channel between the outlet of the side hole 8 and the bulge balloon 6, thereby reducing the formation of turbulence and improving the stability of blood flow.

[0054] In addition, on the side of the bulging airbag 6 away from the aortic counterpulsation balloon 5, an acute angle is formed with the wall of the cannula 1. This acute angle structure forms an effective clamping point between the cannula 1 and the arterial vessel wall, enabling the cannula 1 to be more firmly fixed in the blood vessel. At the same time, due to the cooperative setting of the obtuse angle and acute angle of the bulging airbag 6 and its connection state with the blood vessel wall in its designed form, the flow process of blood in the blood vessel is promoted to maintain a gentle flow velocity gradient, thereby effectively reducing the drastic change in flow velocity and reducing the risk of turbulence occurrence.

[0055] After the bulging airbag 6 is inflated to fix the cannula 1, the aortic counterpulsation balloon 5 inflates and deflates synchronously according to the patient's heart rate. During the inflation process, the aortic counterpulsation balloon 5 blocks the blood flow on both sides of it, restricting the blood flow in the aortic lumen to a certain extent. At the same time, the expansion and contraction of the arterial blood vessel are intervened, thereby achieving the effect of counterpulsation. When the aortic counterpulsation balloon 5 deflates, the blood in the artery can flow again and is no longer blocked by the aortic counterpulsation balloon 5, forming a pulsatile blood flow.

[0056] The above description is only for the purpose of illustrating the present invention. It should be understood that the present invention is not limited to the above embodiments, and various flexible forms conforming to the idea of the present invention are within the protection scope of the present invention.

Claims

1. A femoral artery cannula for VA-ECMO of lower limb blood perfusion, characterized in that, Comprising: A cannula (1), the front end of which is guided into the femoral artery through a puncture guide wire (2); An output hole (3) is communicatively provided at the front end of the cannula (1), and the area of the front end of the cannula (1) where the output hole (3) is provided is defined as area A (101); A connector (4) is communicatively provided at the rear end of the cannula (1); An aortic counterpulsation balloon (5) is provided at the middle part of the outer surface of the cannula (1), and its front end is close to area A (101); A bulging balloon (6) is provided on the cannula (1) at the rear end of the aortic counterpulsation balloon (5), wherein one end of the bulging balloon (6) facing the aortic counterpulsation balloon (5) is in an obtuse angle with the wall of the cannula (1), and the end away from the aortic counterpulsation balloon (5) is in an acute angle with the wall of the cannula (1); An airbag port (7) is provided on the cannula (1) on the side of the bulging balloon (6) away from the aortic counterpulsation balloon (5) for inflating the aortic counterpulsation balloon (5) and the bulging balloon (6); A side hole (8) is provided on the cannula (1) at the middle part of the front end of the bulging balloon (6) and the rear end of the aortic counterpulsation balloon (5), and the distance between the outlet end of the side hole (8) and the bulging balloon (6) and the contralateral blood vessel wall is gradually flattened.

2. The VA-ECMO femoral artery cannula for lower limb blood perfusion according to claim 1, wherein There are multiple output holes (3), which are annularly distributed in area A (101).

3. The VA-ECMO femoral artery cannula for lower limb blood perfusion according to claim 1, wherein An annular guide wire (9) is provided on the surface of the cannula (1) in area A101 and at the middle part of the aortic counterpulsation balloon (5).

4. The VA-ECMO femoral artery cannula for lower limb blood perfusion according to claim 1, characterized in that, There are two airbag ports (7), and the two airbag ports (7) are symmetrically arranged on the cannula (1) and are communicatively provided with the aortic counterpulsation balloon (5) and the bulging balloon (6) respectively.

5. The VA-ECMO femoral artery cannula for lower limb blood perfusion according to claim 1, wherein The diameter of the part of the front end of the cannula (1) placed under the skin is smaller than that of the rear end.

6. The VA-ECMO femoral artery cannula for lower limb blood perfusion according to claim 1, characterized in that, The connector (4) includes a plastic connector (41) and a liquid injection port (42); The plastic connector (41) is communicatively provided at one end of the cannula (1); The liquid injection port (42) is communicatively provided on the plastic connector (41).

7. A catheterization method for a VA-ECMO femoral artery cannula for lower limb blood perfusion according to any one of claims 1-6, characterized in that: First, under the guidance of the puncture guide wire (2), the front end of the cannula (1) is directed towards the proximal end of the femoral artery; the bulging balloon (6) and the aortic counterpulsation balloon (5) are located inside the femoral artery, and the side hole (8) is controlled to face the distal end of the femoral artery, and perfusion is carried out into the cannula (1) through the connector (4); Then, the bulging balloon (6) and the aortic counterpulsation balloon (5) are inflated through two balloon ports (7) respectively. After inflation, the bulging balloon (6) can be used to position the cannula (1) to prevent the cannula (1) from falling off; the side of the inflated bulging balloon (6) facing the aortic counterpulsation balloon (5) forms an obtuse angle with the wall of the cannula (1), thereby reducing the width of the blood flow channel between the outlet of the side hole (8) and the bulging balloon (6) and reducing the formation of turbulence; at the same time, the side of the bulging balloon (6) away from the aortic counterpulsation balloon (5) forms an acute angle with the cannula (1), and is clamped at the acute angle with the position of the blood vessel cannula. After clamping, the surface of the bulging balloon (6) forms an obtuse contact area with the blood vessel wall, reducing the occurrence of turbulence on the side of the bulging balloon (6) away from the aortic counterpulsation balloon (5) and improving the fixing stability of the cannula (1). Then, the aortic counterpulsation balloon (5) is inflated and deflated synchronously with the patient's heart rate. During the inflation process, the blood flow on both sides of the aortic counterpulsation balloon (5) is blocked, and at the same time, the arterial blood vessels are dilated and contracted. During the deflation process, the blood in the artery flows again and is not blocked by the aortic counterpulsation balloon (5), forming a pulsatile blood flow.

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