Bidirectional blood pump and unidirectional filter trap and system including the same

Abstract

A blood pump system switchable between a first flow direction and a second flow direction includes a filter trap and a blood pump. The blood pump has an impeller configured to rotate at a predetermined speed in a first rotation direction to generate a fluid flow in the first flow direction at a first pressure and a first flow rate. The impeller is configured to rotate at a predetermined pump speed in a second rotation direction to generate a fluid flow in the second flow direction at a second pressure and a second flow rate. With the impeller operating at the predetermined pump speed, the first flow rate and the first pressure are different from the second flow rate and the second pressure. The filter trap includes a check valve configured to remain closed with a fluid flow in the first direction and open with a fluid flow in the second direction.

Description

Technical Field

[0001] The present invention generally relates to blood pumps, and more specifically to bidirectional blood pumps and unidirectional filter traps.

Background Art

[0002] When treating a patient, it may be necessary to generate blood flow using an artificial pump. In a perfusion configuration, blood is pumped from one compartment of the circulation to another blood pump. Typically, blood is pumped in a forward flow, which means the natural direction of blood flow. This can be in series or parallel with respect to the original blood flow, determined by the inlet and outlet connections of the pump. Thereafter, the blood may undergo some kind of treatment or procedure within the artificial circuit before returning to circulate within the patient. In reverse flow, the blood is pumped in a direction opposite to the natural direction of blood flow. Regardless of the direction of flow, the blood pump needs to approximately match the pressures in the veins and arteries to which the blood pump is fluidly coupled. Otherwise, it may cause damage to the blood vessels. The normal pressure in systemic veins is usually in the range of 2 - 10 mmHg, the normal pressure in arteries is usually in the range of 100 - 140 mmHg, and the mean pressure is in the range of 65 - 95 mmHg.

[0003] Perfusion involves pumping a liquid through the body in a physiologically normal flow to provide gas exchange and nutrient supply to tissues and organs. Retrograde perfusion involves pumping a liquid through the body in a physiologically abnormal flow. Conventional methods for performing perfusion and retrograde perfusion are complex and involve a risk of human error. For example, many blood pumps operate only in a single direction. To change the direction of flow (e.g., from forward flow to reverse flow), the pump needs to be disconnected and reconnected. In current continuous flow pumps that can operate bidirectionally, it is necessary to change the pump speed between forward flow and reverse flow considering the normal range of pressure difference between the vein and the artery. What is even more concerning when switching from forward flow or perfusion to reverse flow or retrograde perfusion is the possibility of technical complications resulting from the operation, and above all, bleeding and thrombosis.

Summary of the Invention

Means for Solving the Problems

[0004] The present disclosure relates to a bidirectional blood pump system for perfusion and retrograde perfusion. The bidirectional blood pump system can operate at the same pump speed for both perfusion and retrograde perfusion. The bidirectional blood pump system can include a filter trap, an alarm, a gas exchanger, a vacuum device, or a heat exchanger.

[0005] In one aspect of the present disclosure, the blood pump includes a pump housing and an impeller. The pump housing has a first connector configured as a fluid inlet to the pump housing in a first flow direction and a fluid outlet from the pump housing in a second flow direction, and a second connector configured as a fluid inlet to the pump housing in the second flow direction and a fluid outlet from the pump housing in the first flow direction. The impeller is disposed within the pump housing. The impeller is configured to rotate in a first rotational direction at a predetermined speed to generate a fluid flow in the first flow direction at a first pressure and a first flow rate. The impeller is configured to rotate in a second rotational direction opposite to the first rotational direction at a predetermined pump speed to generate a fluid in the second flow direction at a second pressure and a second flow rate. The first flow rate is greater than the second flow rate, and the first pressure is greater than the second pressure.

[0006] In one aspect, the impeller includes a body and vanes. The body can have a first segment and a second segment. The vanes extend radially outward from the body and can be wound helically around the second segment of the body. The vanes can have an inclination angle such that the radially outer portion of the vanes is farther from the first segment than the radially inner portion of the vanes. The vanes can be wound helically around the second segment of the body with a variable pitch such that the portion of the vanes close to the first segment has a smaller pitch than the portion of the vanes far from the first segment. The first segment can be substantially oval, and the second segment can be frustoconical. The product of the first flow rate and the first pressure may be different from the product of the second flow rate and the second pressure. The product of the first flow rate and the first pressure may be greater than the product of the second flow rate and the second pressure.

[0007] In a particular aspect, the first pressure of the fluid flow generated by the blood pump is greater than the second pressure. The first flow rate of the fluid flow generated by the blood pump may be greater than the second flow rate. The second flow rate can be between 30% and 50% of the first flow rate. The first pressure can be in the range of 100 mmHg to 140 mmHg. The first flow rate can be in the range of 2.8 L / min to 3.5 L / min. The second pressure can be in the range of 2 mmHg to 10 mmHg. The second flow rate can be from 1.2 L / min to 1.5 L / min.

[0008] In another aspect of the present disclosure, the filter trap includes a housing, a first trap connector, a second trap connector, a perforated wall, and a check valve (one-way valve). The perforated wall is disposed within the housing and defines an internal chamber and an external chamber within the housing. The check valve separates the internal chamber into an inlet section and a trap house.

[0009] In certain embodiments, the perforated wall defines a plurality of perforations. The perforations can have a diameter in the range of 50 μm to 100 μm. The check valve is configured to remain closed when fluid flows through the pump housing in a first flow direction and to open when fluid flows through the pump housing in a second flow direction. The check valve can have two flexible members attached to the perforated wall. The two flexible members can be configured to engage each other in a closed position and to separate from each other in an open position. The two flexible members are self-biased towards the closed position. The perforated wall can include a first perforated portion and a second perforated portion. The first perforated portion can be separated from the second perforated portion by a non-perforated portion. Each of the two flexible members can have a wall engagement portion configured to engage the non-perforated portion when the two flexible members are in the open position. When each flexible member is in the open position and engaged with the non-perforated portion of the perforated wall, each flexible member can define a trap chamber having the perforated wall. The second perforated portion can be separated from the trap house within each respective trap chamber by the flexible member. Fluid flow through the filter trap in the second flow direction can be prevented from flowing through the second perforated portion by the flexible member engaged with the non-perforated portion. The perforated wall can include a third perforated portion configured to be disposed in direct fluid communication with the external chamber and the inlet section. The filter trap can include a third trap connector in direct fluid communication with the trap house. The third trap connector can be configured to fluidly couple the filter trap to a vacuum device.

[0010] In another aspect of the present disclosure, a blood pump system includes any blood pump detailed herein and any filter trap detailed herein. The blood pump system is switchable between a first flow direction and a second flow direction and includes a filter trap and a blood pump. The blood pump system includes a pump housing. The pump housing has a first connector configured as a fluid inlet to the pump housing in the first flow direction and as a fluid outlet from the pump housing in the second flow direction, and a second connector configured as a fluid inlet to the pump housing in the second flow direction and in fluid communication with a filter trap configured as a fluid outlet from the pump housing in the first flow direction. The blood pump housing has an impeller disposed within the pump housing. The impeller is configured to rotate in a first rotational direction at a predetermined speed to generate a fluid flow in the first flow direction at a first pressure and a first flow rate. The impeller is configured to rotate in a second rotational direction opposite the first rotational direction at a predetermined pump speed to generate a fluid flow in the second flow direction at a second pressure and a second flow rate. The product of the first flow rate and the first pressure is different from the product of the second flow rate and the second pressure.

[0011] In certain aspects, the blood pump system includes a first tube fluidly coupled to the pump housing around the first connector. The first tube can be configured to be fluidly coupled to a first blood vessel of a human body. The blood pump system can include a second tube fluidly coupled to the pump housing around the second connector and configured to be fluidly coupled to a second blood vessel of a human body.

[0012] In one aspect, the blood pump system includes a gas exchanger fluidly coupled to the blood pump. The blood pump system can include a heat exchanger fluidly coupled to the pump housing. The heat exchanger can be configured to maintain a desired temperature of the fluid. The blood pump system can include a vacuum device. The vacuum device can be fluidly coupled to the filter trap.

[0013] In another aspect of the present disclosure, the kit includes a blood pump system sealed in a sterile (sterilized) package. The kit can include any of the blood pump systems described herein. Any of the blood pumps, blood pump systems, and kits described herein can operate according to any of the methods described herein.

[0014] In another aspect of the present disclosure, a method of pumping blood in a first direction and a second direction includes inserting a first tube fluidly coupled to a blood pump into a first blood vessel of a patient; inserting a second tube fluidly coupled to the blood pump into a second blood vessel of the patient; operating the blood pump at a first operating pump speed such that blood flows through the blood pump in a first flow direction to the first blood vessel of the patient at a first pressure and a first flow rate; and operating the blood pump at a first operating pump speed such that blood flows through the pump in a second flow direction to the second blood vessel at a second pressure and a second flow rate. The product of the first pressure and the first flow rate is different from the product of the second pressure and the second flow rate.

[0015] Furthermore, any of the embodiments or aspects described herein can be used in combination with any or all of the other embodiments or aspects described herein, to the extent not inconsistent.

[0016] Various aspects of the present disclosure are described below with reference to the drawings, which are incorporated herein and form a part hereof, and which are not necessarily drawn to scale.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 3C

Figure 3D

Figure 3E

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

DETAILED DESCRIPTION OF THE INVENTION

[0018] Here, the present disclosure will be more fully described with reference to its exemplary embodiments, with reference to the drawings in which like reference numerals indicate like or corresponding elements in each of several drawings. These exemplary embodiments are described so that the present disclosure is thorough and complete and conveys the scope of the present disclosure to those skilled in the art. Features from one embodiment or aspect can be combined with features from any other embodiment or aspect in any suitable combination. For example, any individual or collective features of a method aspect or embodiment can be applied to an apparatus, product, or component aspect or embodiment, and vice versa. The present disclosure can be embodied in many different forms and should not be construed as limited to the embodiments described herein; rather, these embodiments are provided so that this disclosure will meet the legal requirements to which it is applied. As used herein and in the appended claims, the singular forms "a", "an", "the", etc. include plural references unless the context clearly dictates otherwise. Further, although quantitative quantities, numerical values, geometric relationships, etc. may be referred to herein, unless otherwise specified, any one or more (but not all) of these may be absolute or approximate values to account for possible tolerances, such as manufacturing tolerances or engineering tolerances.

[0019] As used herein, "antegrade flow" refers to the physiologically normal flow of fluid through the human body. Further, "retrograde flow" refers to the physiologically abnormal flow through the human body. Further, "patient" refers to the recipient of perfusion or retrograde perfusion. As used herein, "operator", "user", or "clinician" refers to the operator of the pump. Further, the term "proximal" refers to the part of the device or its component that is close to the clinician, and the term "distal" refers to the part of the device or its component that is far from the clinician.

[0020] FIG. 1 is an isometric view of a bidirectional blood pump 100 according to an aspect of the present disclosure. FIG. 2 is a cross-sectional side view of the pump 100 according to an aspect of the present disclosure. Referring to FIGS. 1 and 2, the pump 100 includes a connector 102, a connector 104, a motor 106, and an impeller shaft 108. When the pump 100 operates for perfusion or forward flow, the connector 102 is an inlet that receives blood from a patient's vein. The blood is drawn into the pump 100 by the rotation of the impeller shaft 108 including an impeller 110 (see FIGS. 2 and 4A-4E). The blood exits the pump 100 via the connector 104 at a pressure approximately equal to the pressure of the artery of the patient to which the pump 100 is connected. For example, the pressure of the blood exiting the pump 100 operating for perfusion can be between 100 mmHg and 140 mmHg. The volumetric flow rate of the pump 100 operating for perfusion can be between 2.8 L / min and 3.5 L / min. In an exemplary aspect, a tube is connected to the patient's vein and to the connector 102, and the tube is connected to the patient's artery and to the connector 104.

[0021] The flow characteristics of the pump 100 can be represented from a hydraulic perspective, where hydraulics is the product of volumetric flow rate and pressure. For example, the pump 100 operates at a first pump speed with the impeller 110 rotating in a first direction to generate a flow with a first hydraulic. When the pump 100 operates at the first pump speed with the impeller 110 rotating in a second direction opposite to the first direction, the pump 100 generates a flow with a second hydraulic. In some embodiments, the first hydraulic may be greater than the second hydraulic. In an embodiment, the first hydraulic can correspond to forward flow and the second hydraulic can correspond to reverse flow.

[0022] When the pump 100 operates for retrograde perfusion, blood flows in the reverse direction or in a retrograde flow through the pump 100. The connector 104 is an inlet that receives blood from the patient's artery, and the connector 102 is an outlet that directs blood to the patient's vein. When operating for retrograde perfusion, the pressure output to the vein is approximately equal to the pressure of the vein because the impeller shaft 108 operates at the same speed during perfusion despite rotating in the reverse direction. In other words, when rotating in the first direction, the impeller 110 outputs blood with a flow rate and pressure approximately equal to the natural flow rate and pressure of the artery, and when rotating in the opposite second direction, the impeller 110 outputs blood with a flow rate and pressure approximately equal to the natural flow rate and pressure of the vein. Specifically, when the pump 100 is operated for retrograde perfusion at the same pump speed, a retrograde flow with a pressure and flow rate of 30% - 50% of the antegrade flow rate value occurs when the pump 100 is operated for perfusion. For example, the pressure of the blood exiting the pump 100 when operating for retrograde perfusion may be 2 mmHg - 10 mmHg, and the flow rate may be 1.2 L / min - 1.5 L / min. This unique behavior is made possible by the design of the impeller 110, which is described in more detail below in relation to FIGS. 3A - 3E.

[0023] Retrograde perfusion is not physiologically normal, but it provides a certain degree of perfusion and the ability to regulate the temperature of organs and / or tissues. Temperature regulation of tissues and organs is a further characteristic of the perfusion described above. In some applications, retrograde perfusion can be used to wash out emboli and other debris within the vascular system. Retrograde perfusion can provide better blood distribution in situations where there is a chronic or acute occlusion in the arterial circulation. The most common acute occlusion is thromboembolism. Retrograde perfusion can be performed to remove emboli from the patient with improved results compared to perfusion.

[0024] Either antegrade perfusion or retrograde perfusion can be utilized to selectively perfuse an organ or tissue with a drug, such as an anticoagulant, a thrombolytic agent, a drug that improves cell function, or a chemotherapeutic agent for local cancer treatment. This includes solitary malignancies within multiple organs being perfused.

[0025] The motor 106 is coupled to the impeller shaft 108 and configured to drive the impeller shaft 108 bidirectionally (for example, clockwise in the case of perfusion and counterclockwise in the case of retrograde perfusion, although the opposite configuration may be considered depending on the orientation of the impeller vanes). The motor 106 is connected to the controller via the lead wire 112, and the controller supplies power to the motor 106 and controls its operating parameters (such as speed, torque, etc.). The motor 106 includes an output shaft 114 that is coupled to the impeller shaft 108 via a coupler 116. In some embodiments, the output shaft 114 and / or the impeller shaft 108 can include keyways or the like for rotatably coupling these components. The impeller shaft 108 is supported by a bearing 118 and includes an impeller 110. The impeller shaft 108 extends through an impeller housing 120 in which the impeller 110 is located. A seal 122 seals the impeller housing 120 to prevent blood from leaking from the portion where the impeller shaft 108 enters the impeller housing 120.

[0026] The connector 102 is in fluid communication with the impeller housing 120 via a conduit 124, and the connector 104 is in fluid communication with the impeller housing 120 via a conduit 126. During perfusion, blood flows from the connector 102 through the conduit 124 into the impeller housing 120. The impeller 110 pushes the blood out of the impeller housing 120 at a pressure approximately equal to the pressure in the artery to which the pump 100 is connected. Thereafter, the blood flows through the conduit 126 and out through the connector 104.

[0027] Figures 3A - 3E show multiple views of the impeller 110 according to an aspect of the present disclosure. The impeller 110 includes a body 140 having a first segment 128 and a second segment 132. The first segment 128 is relatively oval-shaped with a plane 130. The second segment 132 is frustoconical with vanes 134 that spiral around its perimeter. In some embodiments, the impeller 110 can include multiple vanes 134. The vanes 134 are designed to supply a first flow rate and pressure when operating in a first direction (e.g., clockwise) and a second flow rate and pressure when operating in a second direction (e.g., counterclockwise). In an aspect, the first pressure is between 2 mmHg and 10 mmHg, and the second pressure is between 100 and 140 mmHg. In some aspects, the first flow rate is between 1.2 L / min and 1.5 L / min, and the second flow rate is between 2.8 L / min and 3.5 L / min. The first pressure and second pressure, as well as the first flow rate and second flow rate, can be achieved by the impeller 110 rotating in opposite directions while the pump 100 operates at a single pump speed. The pump speed can be in the range of 4,000 RPM to 8,000 RPM, for example, 6,000 RPM. The various flow characteristics are made possible by the design of the impeller 110.

[0028] As can be seen from FIGS. 3A to 3C, the vane 134 can have an inclination angle such that the radially outer portion of the vane 134 approaches the plane 136 more than the radially inner portion of the vane 134 in the axial direction. The inclination angle can be in the range of 30 degrees to 65 degrees, for example 48.6 degrees, with respect to the central axis of the impeller 110. The inclination angle of the vane 134 with respect to the central axis of the impeller 110 can be constant or variable. The inclination angle of the vane 134 can be large at the axially outer portion of the vane 134 and small at the axially inner portion of the vane 134. The vane 134 can project from the second segment 132 with a variable radial length. At the axially inner point, the vane 134 can project from the second segment 132 with a smaller radial length, and at the axially outer point, the vane 134 can project from the second segment 132 with a larger radial length. For example, the leading edge of the vane 134 positioned inward along the body of the impeller 110 can have an inclination angle that is smaller or larger with respect to the central axis of the impeller 110 than the trailing edge of the vane 134 positioned outward along the body of the impeller 110, and can project from the segment of the impeller 110 with a smaller or larger radial length. In some embodiments, the inclination angles and the lengths of the radial projections of the leading and trailing edges of the vane 134 can be interchanged. The vane 134 can be wound spirally around the body of the impeller 110 at a constant pitch or a variable pitch. For example, the vane 134 at the leading edge can have a pitch in the range of 1 to 6 millimeters, for example 4 millimeters, and the vane 134 at the trailing edge can have a pitch in the range of 50 to 80 millimeters, for example 64 millimeters.

[0029] Other means of achieving a bidirectional flow are also conceivable. For example, it can be achieved by a control system designed to rotate the impeller at different speeds for the forward and reverse flows. This can be achieved using a standard blood pump and continuously adjusting the speed of the shaft based on the direction of the flow or switching between individual speed setting points. The speed adjustment can be passive, encoded, for example, in a mechanism, circuit, or programming. Alternatively, the speed adjustment can be active. Active speed adjustment can be an open loop controlled via a switch or dial, or a closed loop derived from feedback, for example, from flow rate and pressure sensors.

[0030] Figure 4 is an isometric view of the filter trap 200 according to an aspect of the present disclosure. Figure 5 is an exploded assembly view of the filter trap 200 according to an aspect of the present disclosure. Figure 6 is an isometric view of the filter trap 200 according to an aspect of the present disclosure. Figure 7 is an isometric view of the filter trap 200 according to an aspect of the present disclosure. In some aspects, the filter trap 200 can be used in combination with the pump 100. In other aspects, the filter trap 200 can be used with other devices. Arrow F R indicates the direction of the reverse flow through the filter trap 200. Arrow F A indicates the direction of the forward flow through the filter trap 200. Arrow F V indicates the direction of the vacuum flow exiting the filter trap 200.

[0031] The filter trap 200 includes a housing 202 and connectors 204, 206, and 208. Connectors 204 and 206 attach the filter trap 200 to, for example, a tube that carries blood. In some embodiments, the filter trap 200 is arranged in series with the pump 100, the connector 206 is connected to the connector 204 via a tube, and the connector 206 is connected to a patient's artery. The connector 208 is an outlet, which enables, for example, emboli that have entered the housing 202 to be removed from the blood passing through the filter trap 200.

[0032] In the embodiments of FIGS. 4 - 6, the housing 202 is formed by a first half 210 and a second half 212. The half 210 includes the connectors 204, 206, and 208. The half 212 includes a perforated wall 214 and a check valve 216. The perforated wall 214 includes a plurality of perforations 230, 232, 234 sized to allow blood to pass through but prevent the passage of emboli. For example, the perforations 230, 232, 234 can have diameters in the range of 50 μm to 100 μm. The perforated wall 214 can have a first perforated portion 230, a second perforated portion 232, a third perforated portion 234, and a non - perforated portion 238. In some embodiments, the entire surface of the perforated wall 214 includes perforations. The perforated wall 214 divides the housing 202 into an external chamber 220 formed between the wall of the housing 202 and the outside of the perforated wall 214 and an internal chamber 222.

[0033] The valve 216 is formed from two flexible members 228, each of which can include a wall engagement portion 218. Each of the flexible members 228 of the valve 216 can be self - biasing towards the closed position of the valve 216, as shown in FIG. 6. The flexible member 228 is biased to move away when the flow is from the connector 204 towards 206, and is biased towards the closed position when the flow is from the connector 206 towards 204, as shown in FIG. 7. The two flexible members 228 of the valve 216 are attached to the perforated wall 214 within the internal chamber 222 and further define an internal trap house 224 and an inlet section 240 thereinside. The valve 216 can be made of silicone rubber, polycarbonate or the like. This configuration can help capture emboli removed from the artery during retrograde perfusion. For example, an embolus is removed from the artery during retrograde perfusion, flows into the filter trap 200 together with the blood, and enters through the connector 204. When the blood flows from the connector 204 to the connector 206 during retrograde perfusion, the embolus enters the filter trap 200, flows past the valve 216 (which is open due to the flow), and finally remains on the perforated wall 214 because the embolus is larger than the perforations in the perforated wall 214. When the pump 100 is turned off and the flow stops, the valve 216 closes due to its self - biasing, and any emboli within the filter trap 200 are trapped inside. These emboli can be aspirated through the connector 208. However, even if perfusion is performed without the emboli being removed, the emboli cannot exit the filter trap 200 because the valve 216 is in the closed position during perfusion. The blood can still pass through the filter trap 200, easily pass through the perforated wall 214, and exit through the connector 204 to the outside.

[0034] The filter trap 200 is configured to collect a large or significant amount of plugs, and the fluid is capable of continuing to pass through other portions of the third perforated portion 234 when the fluid flow passing through the first perforated portion 230 and the second perforated portion 232 of the perforated wall 214 is obstructed. Such a flow bypasses the trap house 224 and selects the external chamber 220 to maintain the flow rate parameters. During the reverse flow, the flexible member 228 of the valve 216 can be biased by the flow, and the wall engagement portion 218 engages with the first non-perforated portion 238 of the perforated wall 214 so that the flow through the second perforated portion 232 is restricted. When the wall engagement portion 218 of the flexible member 228 engages with the unperforated portion 238, the flexible member 228 can form the trap chamber 226. The trap chamber 226 can capture plugs within the trap house 224 during the reverse flow F R between them.

[0035] In some embodiments, the pump 100 can switch between the forward flow F A and the reverse flow F R multiple times during a single operation. In some cases, the filter trap 200 may collect plugs in the trap house 224 during a period prior to the reverse flow F R . If plugs remain in the trap house 224, the forward flow F A can backwash the first perforated portion 230, and the plugs captured against the first perforated portion 230 are removed from the first perforated portion 230 and move towards the flexible member 228 of the valve 216 in the closed position and / or the second perforated portion 232. Returning from the forward flow F A to the reverse flow F R causes the flexible member 228 of the valve 216 to capture previously captured plugs between the flexible member 228 and the perforated wall 214 within the trap chamber 226 defined between the flexible member 228 and the section of the perforated wall 214 that defines the third perforated portion 234. In some embodiments, from the reverse flow F R to the forward flow F AThe switch to can be interrupted by a momentary halt in the flow that allows the flexible member 228 of the valve 216 to self-urge itself back to the closed position. Reverse flow F R and forward flow F A Providing a momentary halt in the flow between can prevent the release of the captured plug.

[0036] In some cases, the plug can be removed by perfusion. In such cases, the plug can be captured in the third perforated portion 234 of the perforated wall 214. Reverse flow F R Once is initiated, the angle of the third perforated portion 234 of the perforated wall 214 is such that the direct flow through the valve 216 is selected to pass through the third perforated portion 234 and the wall engagement surface 218 of the valve 216 is urged to contact the non-perforated portion 238 of the perforated wall 214, and the flow is directed to pass through the first perforated portion 230 of the perforated wall 214. Thus, during reverse flow F R the flow can be restricted to pass through the third perforated portion 234 and prevented from passing through the second perforated portion 232. The trap chamber 226 defined between the flexible member 228 of the valve 216 and the perforated wall 214 can capture the plug during a previous momentary period of forward flow F A of.

[0037] The filter trap 200 can include a seal or gasket that provides a better fluid seal. The housing 202 can have a two-piece structure as shown, or can have a one-piece structure. The main bodies 210 and 212 of the housing can be fused by any suitable method, such as ultrasonic welding or adhesion by an adhesive.

[0038] Filter trap 200 can be used for purposes including, but not limited to, collecting thromboemboli, other embolic substances, non-embolic in situ thrombi, or other debris, regardless of the presence or absence of the bidirectional pump 100. Diseases for which the use of filter trap 200 may be relevant, regardless of the presence or absence of pump 100, include, but are not limited to, acute myocardial infarction / coronary insufficiency syndrome, acute aortic occlusion, atheroembolism, thrombotic / embolic stroke, pulmonary embolism, or deep vein thrombosis.

[0039] FIG. 8 is a perspective view of a blood pump system 300 according to an aspect of the present disclosure. The blood pump system 300 includes a bidirectional blood pump 100, an arterial cannula 310, and a vascular cannula 320. The blood pump system 300 can include a filter trap 200, an alarm 330, a vacuum device 340, a gas exchanger or oxygen supplier 350, and a heat exchanger 360.

[0040] As described above, the arterial cannula 310 is fluidly coupled to the bidirectional blood pump 100 at the connector 104, and the vascular cannula 320 is fluidly coupled to the bidirectional blood pump 100 at the connector 102. The filter trap 200 can be connected in series with the bidirectional blood pump 100 between the arterial cannula 310 and the connector 104. The filter trap 200 operates within the blood pump system 300 as described above, and the check valve 216 opens only during retrograde perfusion.

[0041] Alarm 330 can be connected to the bidirectional blood pump 100 and is configured to sound or give a warning in response to the impeller 110 operating outside the set range of rotational speed or outside the limit value of the desired rotational speed, for example, operating between 4,000 and 8,000 RPM, or between 5,000 RPM ± 500 RPM, or between 5,000 RPM ± 10%. When setting the alarm 330, it is necessary to set only one operating speed value for both perfusion and retrograde perfusion. Setting the alarm 330 to a single warning point for both perfusion and retrograde perfusion is due to the bidirectional blood pump 100 operating at the same rotational speed for both perfusion and retrograde perfusion. Alarm 330 can be configured to give a warning in response to a change in pressure or a change in flow rate that exceeds the desired parameters. In an embodiment, alarm 330 can be connected to a pressure sensor that measures the flow pressure through the blood vessel. For example, alarm 330 may sound when the pressure in the forward flow is below 100 mmHg or exceeds 140 mmHg. In an embodiment, alarm 330 can be connected to a flow meter that measures the flow rate through the blood vessel. For example, the alarm may sound when the flow rate in the forward flow is below 2.8 L / min. or exceeds 3.5 L / min. Alarm 330 can be configured to give a warning to the operator with an audible sound, a visual indicator, a tactile feedback, or some other suitable indicator.

[0042] The blood pump system 300 can include a vacuum device 340. The vacuum device 340 can be fluidly coupled to the filter trap 200 at the connector 208. The vacuum device 340 can v enable the removal of the emboli trapped in the filter trap 200 during retrograde perfusion by generating a vacuum flow F. By removing debris from the filter trap 200 during the operation of the pump 100, a long-term perfusion operation or the removal of a large amount of debris from the patient can be enabled. By removing the debris collected from the filter trap 200, a better flow through the pump 100 can be enabled, which can help maintain the flow rate and pressure provided by the pump 100.

[0043] The blood pump system 300 can include a gas exchanger or an oxygen supplier 350 to replenish oxygen to the perfused or retrograde perfused blood. The oxygen supplier 350 can be added in series with the bidirectional blood pump 100. Incorporating the oxygen supplier 350 may be advantageous when performing perfusion over a long period.

[0044] The blood pump system 300 can include a heat exchanger 360 for adjusting the temperature of the perfusion fluid. By adjusting the temperature of the perfusion fluid, heat damage to tissues and organs can be prevented, and the patient can be prevented from experiencing hypothermia or hyperthermia. The heat exchanger 360 can heat or cool the perfusion fluid. For example, in short-term perfusion, the bidirectional blood pump 100 may act as a heat sink and reduce the blood temperature below the desired temperature for perfusion. Conversely, in long-term perfusion, the bidirectional blood pump 100 may become warm due to long-term operation and raise the temperature of the perfused blood above the desired temperature.

[0045] The above-mentioned accessories of the blood pump system 300, such as the oxygen supplier 350, can change the flow rate and pressure characteristics of the pump 100. Such accessories may require a change in the operating speed of the pump 100. For example, including the oxygen supplier 350 may require an increase in the operating speed of the pump 100, for example, an increase of up to 50 RPM may be required.

[0046] FIG. 9 is a perspective view of a blood pump kit 400 according to the present disclosure. The kit 400 is sterilized and can be provided to a clinician, who can open it near the patient in an operating room or within a sterile area for use. The kit 400 includes a pump 100, a filter trap 200, an arterial cannula 310, a vascular cannula 320, and a vacuum device 340. The kit 400 can include an alarm 330, an oxygen supply 350, and / or a heat exchanger 360. The components of the kit 400 can be sealed by any suitable means, such as a plastic wrapping 410. The components of the kit 400 can be sealed together or individually. The kit 400 can be assembled and operated as described above in connection with the blood pump system 300.

[0047] FIG. 10 is a flowchart showing a method of pumping blood according to an aspect of the present disclosure. Method 1000 includes inserting a first cannula into a first blood vessel, such as an artery (step 1010), and inserting a second cannula into a second blood vessel, such as a vein (step 1020). With the first cannula and the second cannula inserted into the first blood vessel and the second blood vessel, respectively, the bidirectional blood pump 100 can generate blood flow in a first direction (step 1030). The direction of flow can be selectively switched to a second direction of flow (step 1040). For example, the bidirectional blood pump 100 can selectively switch between forward flow operation and reverse flow operation. The step of generating blood flow in the first direction (step 1030) can be either forward flow or reverse flow, and the step of generating blood flow in the second direction (step 1040) can be either forward flow or reverse flow. The pump 100 can operate in only one direction for the entire procedure, or can operate in both the first direction (step 1040) and the second direction (step 1040). In some embodiments, the filter trap 200 can be connected in series with the bidirectional rotary pump 100. When operating in reverse flow, the filter trap 200 can collect debris removed during retrograde perfusion, such as thromboemboli (step 1032). If the filter trap 200 is included, the method can include removing the debris collected from the filter trap 200 (step 1034). In certain embodiments, a vacuum device 340 can be connected to the filter trap 200 to remove the debris collected therein (step 1034). The vacuum device 340 can operate continuously or intermittently during reverse flow (step 1034).

[0048] While multiple embodiments of the present disclosure are shown in the drawings, the present disclosure is not intended to be limited thereto, and the scope of the present disclosure is as broad as technology permits and is intended to be interpreted similarly herein. Any combination of the above embodiments is also contemplated and is within the scope of the claims. Accordingly, the above description should not be construed in a limiting sense, but should be construed merely as an exemplification of specific embodiments. Those skilled in the art can envision other changes within the scope of the claims appended hereto.

Explanation of Signs

[0049] 100 Blood pump 200 Filter trap 300 Blood pump system 310 Arterial cannula 320 Vascular cannula 330 Alarm 340 Vacuum device 350 Oxygen supply device 360 Heat exchanger

Claims

1. A blood pump system that can be switched between a first flow direction and a second flow direction, comprising: a filter trap; a blood pump; The blood pump includes: a pump housing; an impeller disposed within the pump housing; The pump housing includes: a first connector configured as a fluid inlet to the pump housing in the first flow direction and as a fluid outlet from the pump housing in the second flow direction; a second connector in fluid communication with the filter trap, the second connector configured as a fluid inlet to the pump housing in the second flow direction and as a fluid outlet from the pump housing in the first flow direction; The impeller is configured to rotate in a first rotational direction at a predetermined pump speed to generate a fluid flow in the first flow direction at a first pressure and a first flow rate, and to rotate in a second rotational direction opposite to the first rotational direction at the predetermined pump speed to generate a fluid flow in the second flow direction at a second pressure and a second flow rate, wherein the first flow rate is greater than the second flow rate and the first pressure is greater than the second pressure.

2. The impeller includes: a body having a first segment and a second segment; vanes extending radially outward from the body and helically wound around the second segment of the body. The blood pump system according to claim 1.

3. The blood pump system according to claim 2, wherein the vanes have an inclination angle such that an outer radial portion of the vanes is farther from the first segment than an inner radial portion of the vanes.

4. The blood pump system according to claim 2, wherein the vanes are helically wound around the second segment of the body with a variable pitch, and a portion of the vanes closer to the first segment has a smaller pitch than a portion of the vanes farther from the first segment.

5. The blood pump system according to claim 2, wherein the first segment is substantially oval and the second segment is frustoconical.

6. ​ ​ ​ The blood pump system according to claim 1, wherein the filter trap includes a check valve configured to remain closed when fluid passes through the pump housing in the first flow direction and to open when fluid passes through the pump housing in the second flow direction.

7. The blood pump system according to claim 6, further comprising a vacuum device fluidly coupled to the filter trap.

8. The blood pump system according to claim 1, wherein the product of the first flow rate and the first pressure is different from the product of the second flow rate and the second pressure.

9. The blood pump system according to claim 8, wherein the product of the first flow rate and the first pressure is greater than the product of the second flow rate and the second pressure.

10. The filter trap includes a housing, a first trap connector, a second trap connector, a perforated wall disposed within the housing and defining an internal chamber and an external chamber within the housing, and the check valve separating the internal chamber into an inlet section and a trap house, The blood pump system according to claim 6.

11. The blood pump system according to claim 10, wherein the perforated wall defines a plurality of perforations, each perforation having a diameter in the range of 50 μm to 100 μm.

12. The blood pump system according to claim 10, wherein the check valve includes two flexible members attached to the perforated wall, the two flexible members being configured to engage each other in a closed position and to separate from each other in an open position.

13. The blood pump system according to claim 12, wherein the two flexible members are self-biased toward the closed position.

14. The blood pump system according to claim 12, wherein the perforated wall includes a first perforated portion and a second perforated portion, the first perforated portion being separated from the second perforated portion by a non-perforated portion.

15. The blood pump system according to claim 14, wherein each of the two flexible members includes a wall engagement portion configured to engage the non-perforated portion when the two flexible members are in the open position.

16. The blood pump system according to claim 15, wherein when each of the two flexible members is in the open position and engaged with the non-perforated portion of the perforated wall, each of the two flexible members defines a trap chamber together with the perforated wall.

17. The blood pump system according to claim 16, wherein the second perforated portion is separated from the trap housing in each trap chamber by the two flexible members.

18. The blood pump system according to claim 17, wherein the fluid flow through the filter trap in the second flow direction is prevented from flowing through the second perforated portion by the flexible member engaging the non-perforated portion.

19. The blood pump system according to claim 14, wherein the perforated wall includes a third perforated portion configured to be disposed in the external chamber and the inlet section in a directly fluidly communicating state.

20. The blood pump system according to claim 10, further comprising a third trap connector in direct fluid communication with the trap housing.

21. The blood pump system according to claim 20, further comprising a vacuum device, wherein the third trap connector is configured to fluidly couple the filter trap to the vacuum device.

22. The blood pump system according to claim 1, further comprising a first tube fluidly coupled to the pump housing and configured to be fluidly coupled to a first blood vessel of a human body around the first connector.

23. The blood pump system according to claim 22, further comprising a second tube fluidly coupled to the pump housing and configured to be fluidly coupled to a second blood vessel of the human body around the second connector.

24. The blood pump system according to claim 1, further comprising a gas exchanger fluidly coupled to the pump housing.

25. The blood pump system according to claim 1, further comprising a heat exchanger fluidly coupled to the pump housing and configured to maintain a desired temperature of the fluid.

26. The blood pump system according to claim 1, wherein the first pressure is greater than the second pressure and the first flow rate is greater than the second flow rate.

27. The blood pump system according to claim 1, wherein the second flow rate is between 30% and 50% of the first flow rate.

28. The blood pump system according to claim 1, wherein the first pressure ranges from 100 mmHg to 140 mmHg and the first flow rate ranges from 2.8 L / min to 3.5 L / min.

29. The blood pump system according to claim 1, wherein the second pressure is in the range of 2 mmHg to 10 mmHg, and the second flow rate is in the range of 1.2 L / min to 1.5 L / min.

30. A kit comprising the blood pump system according to any one of claims 1 to 29, sealed in a sterile package.

31. A method of pumping blood in a first direction and a second direction, comprising: inserting a first tube fluidly coupled to a blood pump into a first blood vessel of a patient; inserting a second tube fluidly coupled to the blood pump into a second blood vessel of the patient; operating the blood pump at a first operating pump speed such that blood flows through the blood pump at a first pressure and a first flow rate in a first flow direction into the first blood vessel of the patient; operating the blood pump at the first operating pump speed such that blood flows through the blood pump at a second pressure and a second flow rate in a second flow direction into the second blood vessel; comprising: wherein the first flow rate is greater than the second flow rate, and the first pressure is greater than the second pressure.

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