A single lumen cannula kit for ECMO-IABP combined support

Abstract

The purpose of this invention is to provide a simple, flexible, and rapid-safe single-lumen cannula kit for combined ECMO-IABP support, enabling rapid and safe switching between ECMO and IABP. The kit includes a cannula and a balloon catheter. The cannula has a blood return outlet at its distal end and a Y-connector at its proximal end. The Y-connector has a first interface for connecting to the ECMO blood return line and a second interface for the balloon catheter to pass through, with a hemostatic valve at the second interface. The balloon catheter is slidably inserted into the cannula, with a balloon at its tip. The balloon passes through the blood return outlet and extends to a position near the lower end of the subclavian artery. This single-lumen cannula structure allows both ECMO blood return and IABP balloon catheters to share the same channel, enabling both treatment functions with a single puncture approach, significantly reducing vascular trauma and infection risks. The balloon catheter can slide freely within the cannula and be withdrawn, supporting flexible switching between various strategies such as "IABP first, then ECMO," "ECMO first, then IABP," and simultaneous treatment.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more specifically to a single-lumen cannula kit for combined ECMO-IABP support. Background Technology

[0002] ECMO (extracorporeal membrane oxygenation) and IABP (intra-aortic balloon counterpulsation) are two important adjunctive treatment techniques in the care of patients with severe circulatory failure. ECMO provides continuous circulatory and respiratory support by drawing venous blood out of the body, oxygenating it, and pumping it back into the arteries; IABP assists the heart in pumping blood by inflating during diastole to increase coronary perfusion and deflating during systole to reduce afterload.

[0003] Clinically, the combined use of ECMO and IABP can achieve complementary advantages, especially suitable for patients with heart failure and cardiac arrest. Numerous clinical studies in recent years have shown that the efficacy of simultaneous use of ECMO and IABP is superior to sequential or single-use administration. A meta-analysis including 5467 patients showed that simultaneous use of IABP and ECMO was significantly associated with a reduction in short-term mortality (adjusted RR: 0.64). Another study on patients with acute myocardial infarction complicated by cardiogenic shock also confirmed that the 30-day survival rate was significantly improved in the group using simultaneous VA-ECMO and IABP compared to the group using ECMO alone (65.2% vs 39.1%).

[0004] Chinese invention patent application CN116271418A discloses a dual-lumen parallel cannula that integrates the ECMO blood return channel and the IABP catheter channel in the same cannula. Although this approach achieves dual function through a single access route, once the dual-lumen cannula is inserted, the functional channels of ECMO and IABP are occupied simultaneously, and cannot be independently removed or activated as needed, thus lacking flexibility in clinical strategy selection. Summary of the Invention

[0005] The purpose of this invention is to provide a single-lumen cannulation kit for ECMO-IABP joint support that is simple in structure, flexible in operation, and can realize rapid and safe conversion between ECMO and IABP.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a single-lumen cannula kit for ECMO-IABP combined support, comprising a cannula and a balloon catheter, wherein the distal end of the cannula is provided with a blood return outlet and the proximal end is provided with a Y-type connector, the Y-type connector having a first interface for connecting the ECMO blood return line and a second interface for the balloon catheter to pass through, and a hemostatic valve is provided at the second interface; the balloon catheter is slidably inserted into the cannula, and the front end of the balloon catheter is provided with a balloon; the balloon passes through the blood return outlet and extends to a position near the lower end of the subclavian artery.

[0007] Furthermore, after the balloon catheter is inserted into place, a sliding support is provided at the position corresponding to the distal end of the cannula. The outer diameter of the sliding support is less than or equal to the inner diameter of the cannula, and the sliding support forms a sliding fit with the inner wall of the cannula to limit the radial movement of the balloon catheter.

[0008] Furthermore, the sliding support is a ring-shaped structure, and its outer wall is provided with support protrusions that contact the inner wall of the cannula, forming a channel for blood to flow through between the support protrusions.

[0009] Furthermore, the sliding support is sleeved and fixed on the outer wall of the balloon catheter, and moves axially synchronously with the balloon catheter.

[0010] Furthermore, one or more sidewall blood return openings are provided on the sidewall of the cannula. When the balloon is in place, the sidewall blood return openings are located on the proximal side of the sliding support and are arranged to avoid contact with it.

[0011] Furthermore, the sliding support is cylindrical in shape, and a spiral guide groove is provided on its outer wall to guide the blood return in a spiral flow.

[0012] Furthermore, the sliding support includes an integrated balloon and a restraint frame. The integrated balloon is sleeved on the outer wall of the balloon catheter, and the restraint frame is disposed in the inner cavity of the integrated balloon. The restraint frame includes multiple restraint parts spaced apart along the circumference of the balloon catheter, and each restraint part extends along the axial direction of the balloon catheter. When the integrated balloon expands, the restraint frame restricts the outward expansion of a local area of ​​the balloon connected to it, and the restrained balloon area forms an axially extending blood flow channel on the outer periphery of the balloon. The unrestrained balloon area expands outward and contacts and cooperates with the inner wall of the catheter, restricting the radial sway of the balloon catheter.

[0013] Furthermore, the outer surface of the sliding support is provided with an anticoagulant coating.

[0014] Furthermore, a metal braided layer or a helical spring is embedded in the wall of the cannula.

[0015] In the above-described scheme, a single-lumen cannulation structure is adopted, with the ECMO blood return and IABP balloon catheter sharing the same channel. Only a single puncture approach is needed to achieve both treatment functions, significantly reducing vascular trauma and infection risks. The balloon catheter can slide freely within the cannula and be withdrawn, supporting flexible switching between various strategies such as "IABP first, then ECMO," "ECMO first, then IABP," and simultaneous treatment. The sliding support works in conjunction with the inner wall of the cannula to keep the balloon centrally positioned in the aorta, avoiding eccentric inflation and unilateral friction against the vessel wall, thus improving counterpulsation efficiency while reducing the risk of vascular injury. The blood return opening on the side wall of the cannula reduces blood return resistance and synergizes with balloon counterpulsation, enhancing coronary perfusion and also addressing lower limb blood supply. The spiral guide channel guides ECMO blood return to form a spiral flow, effectively reducing turbulence and eddies, lowering the risk of hemolysis and thrombus adhesion. In summary, this invention has a simple structure, is easy to operate, and enables rapid and safe switching between ECMO and IABP, showing promising clinical application prospects. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the kit; Figure 2 A schematic diagram of a cannula structure with a side wall blood return opening; Figure 3 This is a schematic diagram of the overall structure of the kit in Example 1; Figure 4 This is a schematic diagram of one possible structure of the sliding support in Example 1; Figure 5 This is a schematic diagram of another structure of the sliding support in Example 1; Figure 6 This is a schematic diagram of the overall structure of the kit in Example 2; Figure 7 This is a schematic diagram of a sliding support component in Example 2; Figure 8 This is a first cross-sectional view of the sliding support in Example 2; Figure 9 This is a second cross-sectional view of the sliding support in Example 2; Figure 10 This is the third cross-sectional view of the sliding support in Example 2. Detailed Implementation

[0017] For ease of understanding, we first define the orientations mentioned below: "proximal" and "proximal side" refer to the side closer to the operator / doctor, while "distal" and "distal side" refer to the side farther from the operator / doctor, i.e., the side closer to the heart. The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.

[0018] like Figure 1As shown, a single-lumen cannula kit for combined ECMO-IABP support includes a cannula 10 and a balloon catheter 20. The cannula 10 has a blood return outlet 11 at its distal end and a Y-connector 12 at its proximal end. The Y-connector 12 has a first interface 121 for connecting to the ECMO blood return line and a second interface 122 for the balloon catheter 20 to pass through. A hemostatic valve 123 is provided at the second interface 122. The balloon catheter 20 is slidably inserted into the cannula 10, and a balloon 21 is provided at the front end of the balloon catheter 20. The balloon 21 passes through the blood return outlet 11 and extends to a position near the lower end of the subclavian artery. The single-lumen cannula 10 simultaneously carries both ECMO blood return and IABP balloon catheter access, with only one puncture point, reducing the risk of trauma, bleeding, and infection. Compared with a common-wall double-lumen cannula, the single-lumen cannula does not require customization and can be fabricated using standard tubing, significantly reducing manufacturing costs. While allowing the same flow rate of blood, the single-lumen cannula has a smaller diameter, further reducing the risk of trauma, bleeding, and infection.

[0019] Meanwhile, the balloon catheter 20 slides freely within the cannula 10, and the doctor can independently adjust the position of the balloon or withdraw the balloon catheter 20 as needed, supporting multiple treatment strategies such as "IABP first then ECMO", "ECMO first then IABP", and "IABP and ECMO simultaneously".

[0020] In addition, compared to double-lumen tubes, after the balloon catheter 20 is withdrawn, there is no dead zone where blood stagnates in the cannula 10, and there is no risk of blood flowing directly into the idle cavity and forming a thrombus.

[0021] Because ECMO has a large blood return flow (2-6 L / min), the high-speed blood flow can impact the balloon catheter 20, causing it to deviate and sway. To solve this problem, a sliding support 22 is provided at the position corresponding to the distal end of the cannula 10 after the balloon catheter 20 is inserted. The outer diameter of the sliding support 22 is less than or equal to the inner diameter of the cannula 10. The sliding support 22 forms a sliding fit with the inner wall of the cannula 10 to limit the radial sway of the balloon catheter 20, so that the balloon catheter 20 remains centered at the distal outlet of the cannula 10. The balloon 21 extending out of the cannula 10 is located in the center of the aortic vessel and expands evenly when inflated, avoiding unilateral friction between the balloon 21 and the vessel wall, improving counterpulsation efficiency and reducing the risk of vascular injury. It should be noted that the outer diameter of the sliding support 22 is less than or equal to the inner diameter of the cannula 10. The sliding support 22 only restricts radial movement and does not block the distal blood return outlet 11. Generally, the distal end of the cannula 10 will have a constriction, and the inner diameter of this constriction will be smaller than that of the sliding support 22, forming a natural radial limiting structure to prevent the sliding support 22 from sliding out of the cannula 10. The sliding support 22 cooperates with the proximal hemostatic valve 123 to form a two-point positioning mode of proximal locking and distal limiting, with the middle section freely suspended. This ensures positioning accuracy and avoids the additional friction caused by the full-length support of the balloon catheter 20.

[0022] The sliding support 22 has an annular structure, with supporting protrusions on its outer wall that contact the inner wall of the cannula 10. These protrusions form channels for blood flow. This multi-point contact, rather than full contact, ensures centered positioning while reducing sliding friction, making the balloon catheter 20 easier to push and withdraw. The grooves between the protrusions form axial blood flow channels, allowing ECMO blood return to pass normally through the grooves, avoiding increased resistance to blood return caused by the sliding support 22. The groove structure ensures continuous blood flow around the sliding support 22, eliminating areas of blood stagnation and reducing the risk of thrombosis.

[0023] The sliding support 22 is sleeved and fixed on the outer wall of the balloon catheter 20 and moves axially synchronously with the balloon catheter 20. When the balloon catheter 20 moves axially in the cannula 10, the sliding support 22 moves synchronously with the balloon catheter 20. For the doctor, there is no need to operate the sliding support 22 separately, and the feel is consistent with the conventional IABP operation, without changing the doctor's operating habits.

[0024] Because the sliding support 22 occupies part of the lumen space, local resistance is generated when ECMO blood returns through the area around the sliding support 22, resulting in reduced blood flow to the distal outlet. Therefore, one or more sidewall blood return openings 13 are provided on the sidewall of the cannula 10 to provide additional blood flow channels, such as... Figure 2 As shown, some blood flows out prematurely from the lateral wall opening, preventing all blood from being squeezed into the narrow channel and reducing overall blood return resistance. During diastole, balloon 21 inflates, squeezing blood upwards to increase coronary perfusion. At this time, the blood flow from the lateral wall opening, which is angled upwards, is in the same direction as the upward squeezing of the balloon. The two forces combine to push blood towards the aortic root, enhancing coronary perfusion. The lateral wall opening shunts downwards to ensure lower limb perfusion. The two work synergistically to achieve dual blood supply from the coronary arteries to the lower limbs. Simultaneous outflow from the distal outlet and the lateral wall opening creates a multi-directional blood flow pattern, reducing the blood flow stagnation area around the distal end of the cannula 10 and lowering the risk of local thrombosis. When balloon 21 is in place, the lateral wall blood return opening 13 is located on the proximal side of the sliding support 22 and is arranged to avoid obstructing blood outflow. Example

[0025] like Figure 3 , Figure 4 and Figure 5As shown, the sliding support 22 is cylindrical in shape, with a spiral guide groove 221 on its outer wall. The spiral guide groove 221 guides the blood return in a spiral flow. The spiral flow has superior hydrodynamic properties compared to axial direct flow, significantly reducing turbulence and eddies, thus lowering the impact on the vessel wall and balloon 21. Reduced turbulence means lower shear stress on blood cells and reduced hemolysis; simultaneously, the orderly spiral flow can flush the outer wall of the balloon catheter 20, reducing thrombus adhesion. Therefore, the sliding support 22 simultaneously performs the dual functions of centering and limiting blood flow. Example

[0026] like Figures 6-10 As shown, the sliding support 22 includes an integrated airbag 222 and a restraint frame 223. The integrated airbag 222 is sleeved on the outer wall of the balloon catheter 20, and the restraint frame 223 is disposed in the inner cavity of the integrated airbag 222. The restraint frame 223 includes multiple restraint parts spaced apart along the circumference of the balloon catheter 20, and each restraint part extends axially along the balloon catheter 20. When the integrated airbag 222 expands, the restraint frame 223 restricts the outward expansion of a local area of ​​the airbag connected to it, and the restrained airbag area forms an axially extending blood flow channel on the outer periphery of the airbag. The unrestrained airbag area expands outward and contacts and cooperates with the inner wall of the balloon catheter 20, restricting the radial sway of the balloon catheter 20. Similarly, after inflation, part of the integrated airbag 222 contacts and limits the inner wall of the cannula 10, and there is also a channel for blood to flow through. In this embodiment, after the airbag is deflated, its diameter is small, and it has no impact when passing through the hemostasis valve 123, making the operation convenient.

[0027] Since the sliding support 22 is located in the blood flow channel and is in long-term contact with blood, an anticoagulant coating is provided on the outer surface of the sliding support 22 to reduce platelet adhesion and coagulation, thereby reducing local thrombus formation.

[0028] Furthermore, the cannula 10 has a metal braided layer or a helical spring embedded in its wall to provide radial support, prevent the cannula 10 from bending or twisting in the curved path, and ensure unobstructed blood flow.

[0029] Clinically, this kit is used as follows:

[0030] The operator prepared the work area according to standard aseptic requirements, checked the compatibility of the ECMO cannula and IABP balloon catheter, and confirmed that the outer diameter of the balloon catheter could smoothly pass through the hemostasis valve and the inner lumen of the cannula. The cannula was pre-flushed and vented, and the hemostasis valve was kept closed.

[0031] Using the Seldinger puncture technique, a guidewire is inserted via the right or left femoral artery. The cannula is then advanced along the guidewire into the femoral artery to the target location. After confirming with imaging that the cannula is correctly positioned and that the lateral blood return openings are within the vessel lumen without adhering to the vessel wall, the guidewire is withdrawn. The two ends of the Y-connector are connected to the ECMO tubing, with the first connector connected to the ECMO return line. ECMO is initiated, and the tubing is confirmed to be patent and leak-free, with oxygenated blood flowing from the distal return outlet and the lateral blood return openings, establishing initial circulatory support for the patient. At this time, the hemostatic valve remains closed, and the cannula is used only as an ECMO return line.

[0032] With ECMO continuously running, the guidewire is inserted into the cannula through the hemostasis valve side port at the second interface and advanced to the target position. The balloon catheter is then advanced along the guidewire, gradually advancing until the sliding support is located inside the distal end of the cannula and the IABP balloon extends from the distal blood return outlet. Under fluoroscopic guidance, confirm that the balloon has reached the target position in the descending aorta (2-3 cm distal to the opening of the left subclavian artery). After confirming the position is correct, lock the hemostasis valve to fix the proximal position of the balloon catheter.

[0033] At this point, if the sliding support needs to expand, the balloon can be inflated via the inflation device and inflation catheter. The balloon expands under the constraint of the restraint frame—the restraint frame rod pulls the local area of ​​the balloon inward to form an axial blood flow channel, while the unrestrained area expands outward to fit against the inner wall of the cannula, forming radial support and restricting the radial movement of the balloon catheter inside the distal end of the cannula.

[0034] Connect the proximal end of the balloon catheter to the IABP main unit and start the IABP. The balloon inflates and deflates rhythmically with the cardiac cycle, operating synchronously with ECMO. ECMO continuously returns blood to the artery, providing circulatory support; the IABP inflates during diastole to increase coronary perfusion and deflates during systole to reduce afterload, working synergistically. During synchronous operation of ECMO and IABP, periodically monitor tubing pressure and blood flow to confirm that the sliding support is functioning properly and that there are no abnormalities in the cannula and balloon catheter. If IABP needs to be removed, turn off the IABP main unit, deflate and retract the sliding support, loosen the hemostatic valve, and withdraw the balloon catheter proximally. The cannula remains in place for use as a return vessel for ECMO. If complete cannula removal is required, after turning off ECMO, pull the cannula out of the femoral artery and apply pressure to the puncture site for hemostasis.

[0035] As can be seen from the above usage method, the solution of the present invention also has the following beneficial effects: 1. Reduced puncture points and trauma: This approach allows for simultaneous ECMO blood return and IABP balloon placement via a unilateral femoral artery approach, eliminating the need for separate vascular access and sharing the femoral artery cannulation pathway. This avoids the trauma associated with separate cannulation of both femoral arteries in traditional approaches, reducing the risks of bleeding, infection, and vascular damage.

[0036] 2. Simple and quick operation, suitable for acute and critical illnesses: The combined ECMO and IABP placement time is only 5-10 minutes, significantly shortening the operation time and meeting the rapid treatment needs of acute and critical patients. The step-by-step intervention design of the Y-type connector allows the operator to flexibly decide whether to add IABP according to the patient's real-time condition. The operation procedure is clear and the learning curve is short.

[0037] 3. Flexible and independent IABP removal: The IABP balloon catheter can be removed independently without simultaneous shutdown or cannulation, and ECMO support can continue. This reduces the clinical risks associated with interrupting circulatory support due to IABP removal and provides patients with a flexible option for stepwise treatment.

[0038] 4. Structural standard compatibility and strong adaptability: This solution is compatible with mainstream ECMO arterial cannulas (10-16Fr) and IABP balloon catheters (7-8Fr), without changing the existing equipment interface standards. It can be directly adopted in clinical practice without additional modifications, thus lowering the threshold for promotion and use.

[0039] 5. Reduce nursing burden: Standardized fixed points reduce the number of tubing lines, lower the risk of nursing errors, and reduce the workload of intensive care unit nurses.

[0040] 6. Controllable bleeding risk: The hemostatic valve has a good seal, and the amount of blood exposed during balloon catheter intervention and removal is minimal. There is no risk of blood splashing or leakage when exchanging connectors, which improves the safety of the operation.

[0041] 7. Avoid the risk of thrombosis in unused cavities: This protocol uses a single-lumen catheter, and there is no dead space with blood stagnation in the catheter after the balloon catheter is removed. This eliminates the risk of thrombosis caused by blood stagnation when the second channel is unused, as is the case with the double-lumen catheter protocol, further ensuring patient safety.

[0042] 8. Simplified structure and low manufacturing cost: The cannula has a single-lumen structure, eliminating the need for customized double-lumen common-wall cannulas. Standard tubing can be used for processing, significantly reducing manufacturing costs and making it suitable for mass production. The sliding support component is an independent part that can be selected according to clinical needs without affecting the cannula's versatility.

[0043] For those skilled in the art, the present invention is not limited to the details of the exemplary embodiments described above, but also includes the same or similar structures that can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

Claims

1. A single-lumen cannulation kit for combined ECMO-IABP support, characterized in that, The device includes a cannula (10) and a balloon catheter (20). The cannula (10) has a blood return outlet (11) at its distal end and a Y-type connector (12) at its proximal end. The Y-type connector (12) has a first interface (121) for connecting the ECMO blood return line and a second interface (122) for the balloon catheter (20) to pass through. A hemostatic valve (123) is provided at the second interface (122). The balloon catheter (20) is slidably inserted into the cannula (10). The balloon catheter (20) has a balloon (21) at its front end. The balloon (21) passes through the blood return outlet (11) and extends to a position near the lower end of the subclavian artery.

2. The single-lumen cannulation kit for ECMO-IABP combined support according to claim 1, characterized in that, After the balloon catheter (20) is inserted into place, a sliding support (22) is provided at the position corresponding to the distal end of the cannula (10). The outer diameter of the sliding support (22) is less than or equal to the inner diameter of the cannula (10). The sliding support (22) and the inner wall of the cannula (10) form a sliding fit to limit the radial movement of the balloon catheter (20).

3. The single-lumen cannulation kit for ECMO-IABP combined support according to claim 2, characterized in that, The sliding support (22) is a ring structure, and its outer wall is provided with support protrusions that contact the inner wall of the cannula (10). The support protrusions form a channel for blood to flow through.

4. The single-lumen cannulation kit for ECMO-IABP combined support according to claim 2, characterized in that, The sliding support (22) is sleeved and fixed on the outer wall of the balloon catheter (20) and moves axially synchronously with the balloon catheter (20).

5. The single-lumen cannulation kit for ECMO-IABP combined support according to claim 2, characterized in that, One or more side wall blood return openings (13) are provided on the side wall of the cannula (10). When the balloon (21) is in place, the side wall blood return openings (13) are located on the proximal side of the sliding support (22) and are arranged to avoid collision.

6. The single-lumen cannulation kit for ECMO-IABP combined support according to claim 2, characterized in that, The sliding support (22) is cylindrical in shape, and a spiral guide groove (221) is provided on its outer wall. The spiral guide groove (221) guides the blood return to flow in a spiral shape.

7. The single-lumen cannulation kit for ECMO-IABP combined support according to claim 2, characterized in that, The sliding support (22) includes an integrated balloon (222) and a restraint frame (223). The integrated balloon (222) is sleeved on the outer wall of the balloon catheter (20), and the restraint frame (223) is disposed in the inner cavity of the integrated balloon (222). The restraint frame (223) includes multiple restraint parts spaced apart along the circumference of the balloon catheter (20), and each restraint part extends along the axial direction of the balloon catheter (20). When the integrated balloon (222) expands, the restraint frame (223) restricts the outward expansion of the local area of ​​the balloon connected to it. The restrained balloon area forms an axially extending blood flow channel on the outer periphery of the balloon. The unrestrained balloon area expands outward and contacts and cooperates with the inner wall of the cannula (10), restricting the radial sway of the balloon catheter (20).

8. The single-lumen cannulation kit for ECMO-IABP combined support according to claim 2, characterized in that, The outer surface of the sliding support (22) is provided with an anticoagulant coating.

9. The single-lumen cannulation kit for ECMO-IABP combined support according to claim 1, characterized in that, The cannula (10) has a metal braided layer or a helical spring embedded in its wall.

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