Extracorporeal blood pump assembly and assembly method

Abstract

An extracorporeal blood pump assembly includes a blood pump and an extracorporeal membrane oxygenator (ECMO). The blood pump includes a pump housing, a rotor, and a flow converter located downstream of the rotor for converting a non-axial flow from the rotor into an axial flow. The pump housing defines an inlet and an outlet. The ECMO includes a membrane housing and an oxygenator membrane disposed in the membrane housing. The membrane cassette is detachably connected to the pump housing at one of the pump housing inlet and the pump housing outlet.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application Serial No. 63 / 040,307, filed on June 17, 2020, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present invention relates generally to mechanical blood circulation support systems and more particularly to an extracorporeal blood pump assembly including a combined blood pump and oxygenator. Background Art

[0004] Many types of heart assist devices have been developed for applications where a patient's heart is unable to provide adequate blood circulation, commonly referred to as a heart rhythm disorder or heart failure. For example, patients with chronic heart rhythm disorders may use a ventricular assist device, or VAD, which is implanted in the patient while awaiting a heart transplant or during long-term, purposeful treatment. As another example, patients with acute heart rhythm disorders may use an extracorporeal pump, or circulatory support system, to pump blood out and back into the patient's body. Extracorporeal circulatory support systems may also be used before and after surgery, for example, to direct blood through a patient while surgery is being performed on the heart.

[0005] At least some extracorporeal blood circulation support systems temporarily replace the patient's cardiopulmonary function by pumping blood around or bypassing the patient's heart and lungs. Such extracorporeal blood circulation support systems typically include an oxygenator, such as an extracorporeal membrane oxygenator or ECMO, to provide oxygen to the blood passing through the extracorporeal blood circulation support system.

[0006] At least some extracorporeal blood circulation support systems utilize ECMO units that are separate from the blood pump. The design of such extracorporeal blood circulation support systems may result in relatively large combined pressure drops across the multiple independent units, for example, due to the connections between the pump and the ECMO unit and the associated cross-sectional area changes of the inlets and outlets of the various units. Such pressure drops may be associated with or result in areas of turbulent blood flow or hemolysis.

[0007] Therefore, a need exists for an extracorporeal blood circulation support system that provides improved blood flow through a pump and an oxygenator. Summary of the invention

[0008] The present invention relates to an extracorporeal blood pump assembly, which includes a blood pump and an extracorporeal membrane oxygenator (ECMO). The blood pump includes a pump housing, a rotor, and a flow conversion member located downstream of the rotor to convert a non-axial flow from the rotor into an axial flow. The pump housing defines an inlet and an outlet. The ECMO includes a membrane housing and an oxygenator membrane disposed in the membrane housing. The membrane cassette is detachably connected to the pump housing at one of the pump housing inlet and the pump housing outlet.

[0009] The present invention also relates to an extracorporeal blood pump assembly kit, which includes a blood pump, a first extracorporeal membrane oxygenator (ECMO) and a second ECMO. The blood pump includes a pump housing, a rotor and a flow conversion member located downstream of the rotor to convert a non-axial flow from the rotor into an axial flow. The pump housing defines an inlet and an outlet. The first ECMO can be detachably connected to one of the pump housing inlet and the pump housing outlet, and the second ECMO can be detachably connected to one of the pump housing inlet and the pump housing outlet, so that the first ECMO can be interchanged with the second ECMO. The second ECMO has at least one of the size, volume and gas exchange characteristics different from the first ECMO.

[0010] The present invention also relates to a method for assembling an extracorporeal blood pump assembly. The method includes providing a blood pump including a pump housing, a rotor, and a flow conversion member located downstream of the rotor to convert a non-axial flow from the rotor into an axial flow. The pump housing defines an inlet and an outlet. The method also includes providing an extracorporeal membrane oxygenator (ECMO) including a membrane housing and an oxygenator membrane disposed within the membrane housing. The method also includes removably connecting the membrane housing to the pump housing at one of the pump housing inlet and the pump housing outlet. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic diagram of an extracorporeal blood circulation support system connected to a patient's body.

[0012] Figure 2 Is applicable to Figure 1 A cutaway perspective view of an extracorporeal blood pump assembly of a mechanical blood circulation support system.

[0013] Figure 3 yes Figure 2 An enlarged view of the blood pump of the extracorporeal blood pump assembly.

[0014] Figure 4 yes Figure 3 Schematic diagram of a portion of a blood pump including an example heat exchanger.

[0015] Figure 5 yes Figure 2 A magnified view of the extracorporeal blood pump assembly of an extracorporeal membrane oxygenator (ECMO).

[0016] Figure 6 yes Figure 2Cross-sectional view of an extracorporeal blood pump assembly including an ECMO with a multi-directional fiber oxygenator membrane.

[0017] Figure 7 yes Figure 2 A cut-away perspective view of an extracorporeal blood pump assembly including a reduced volume ECMO.

[0018] Figure 8 yes Figure 2 A perspective view of an extracorporeal blood pump assembly including an ECMO with a removable membrane cassette.

[0019] Fig. 9 Another suitable Figure 1 A cutaway perspective view of an extracorporeal blood pump assembly of a mechanical blood circulation support system. DETAILED DESCRIPTION

[0020] The present invention relates to a mechanical blood circulation support system, and more specifically to an extracorporeal blood pump assembly including a combined blood pump and an oxygenator. Embodiments of the extracorporeal blood pump assembly disclosed herein include an integrated blood pump and an extracorporeal membrane oxygenator (ECMO). For example, compared with a separate or independent blood pump and ECMO module, the design and construction of the extracorporeal blood pump assembly of the present invention is conducive to reducing the drop in blood pressure. For example, an embodiment of the blood pump assembly provides a blood flow path without bends and turns, and the path has a substantially constant cross-sectional area passing through the blood pump and ECMO, thereby reducing or eliminating the nozzle / throat effect that would otherwise be caused by connecting the independent blood pump and ECMO module with a pipe fitting. An embodiment of the blood pump assembly may also be free of a volute, otherwise it may result in a nozzle / throat effect, a blood flow path that is longer than necessary (and the associated pressure drop and larger priming volume), and at least one additional bend in the blood flow path.

[0021] The blood pump assembly of the present invention also facilitates reducing the priming volume of the unit, for example, by eliminating tubing between the blood pump and the ECMO module, and providing modularity for ECMO modules of different sizes (e.g., ECMO modules with different priming volumes for adult and pediatric modules can be interchanged as needed). The modularity of the blood pump assembly also allows the oxygenator membrane of the ECMO to be replaced or discarded without having to discard the blood pump, thereby allowing the blood pump to be cleaned and reused. Embodiments of the blood pump assembly may also include an integrated heat exchanger, thereby eliminating the need for a separate heat exchanger and associated fluid lines (e.g., connecting a separate water heater / water cooler).

[0022] Now referring to the accompanying drawings, Figure 1 Schematic diagram of an extracorporeal mechanical blood circulation support system 10 connected to a blood vessel of a patient 12. The extracorporeal mechanical blood circulation support system 10 includes an extracorporeal blood pump assembly 14, an inflow conduit or first conduit 16, an outflow conduit or second conduit 18, a controller 20, and a power source 22.

[0023] The blood pump assembly 14 includes a blood pump 24, an extracorporeal membrane oxygenator (ECMO) 26, and an inlet 28 and an outlet 30 for connecting flexible tubing thereto. The blood pump assembly 14 may include any suitable pump type that enables the blood pump assembly 14 to function as described herein, including, but not limited to, axial rotary pumps and centrifugal rotary pumps. The ECMO 26 includes an oxygenator membrane (in Figure 1 14 ), which is configured to increase the oxygen concentration and / or reduce the carbon dioxide concentration of the blood pumped by the blood pump assembly 14. The oxygenator membrane may include any suitable oxygenator membrane type that enables the blood pump assembly 14 to function as described herein, including, for example, but not limited to, a fiber bundle. In some embodiments, the system 10 also includes a purge valve ( Figure 1 10) to release air or other gases present in the system 10. The deflation valve may be connected to the outflow tubing 18, for example, or may be integrated into the ECMO 26 (e.g., at the outlet of the ECMO 26).

[0024] The blood pump assembly 14 is connected to a patient's blood vessel through an inflow conduit 16 and an outflow conduit 18. More specifically, an inlet 28 of the blood pump assembly 14 is connected to the inflow conduit 16, and an outlet 30 of the blood pump assembly 14 is connected to the outflow conduit 18. The inflow conduit 16 is connected to the patient's blood vessel, specifically a first peripheral blood vessel 32 in the illustrated embodiment, through a first cannula 34, while the outflow conduit 18 is connected to the patient's blood vessel, specifically a second peripheral blood vessel 36, through a second cannula 38. The blood pump assembly 14 pumps blood from the first peripheral blood vessel 32 through the inflow conduit 16, through the blood pump assembly 14, and back through the outflow conduit 18 to the second peripheral blood vessel 36. In the illustrated embodiment, the first peripheral blood vessel 32 is a femoral vein, and the second peripheral blood vessel 36 is an axillary artery. It should be understood that the connection to the patient's blood vessels shown in the figure is for illustrative purposes only, and the blood pump assembly 14 can be connected to the patient's blood vessels using any other suitable method that enables the extracorporeal mechanical blood circulation support system 10 to perform the functions described herein, such as but not limited to veno-venous (VV) connection and veno-arterial (VA) connection.

[0025] The controller 20 is communicatively coupled to the blood pump assembly 14 and configured to control the operation thereof. For example, the controller 20 is configured to control the operation (e.g., speed) of the blood pump 24. The controller 20 may generally include any suitable computer and / or other processing unit, including any suitable combination of computers, processing units, and / or the like that may be communicatively coupled to one another (e.g., the controller 20 may form all or part of a controller network). Thus, the controller 20 may include one or more processors and associated storage devices that are configured to perform various computer-implemented functions (e.g., perform the methods, steps, calculations, and / or the like disclosed herein). As used herein, the term "processor" refers not only to an integrated circuit contained within a computer as referred to in the art, but also to a controller, a microcontroller, a microcomputer, a programmable logic controller (PLC), an application specific integrated circuit (ASIC), a digital signal processor (DSP), a field programmable gate array (FPGA), and other programmable circuits. In addition, the storage device of the controller 20 may generally include a storage element, including, but not limited to, a non-transitory computer-readable medium (such as a random access memory (RAM)), a computer-readable non-volatile medium (such as a flash memory), a floppy disk, a compact disc read-only memory (CD-ROM), a magneto-optical disk (MOD), a digital versatile disc (DVD), and / or other suitable storage elements. Such a storage device may generally be configured to store suitable computer-readable instructions such that the storage device, when executed by a processor, configures the controller 20 to perform various functions including, but not limited to, controlling the components of the blood pump assembly 14 described herein.

[0026] The power source 22 provides power to the blood pump 24, the controller 20, and other electrical components of the blood pump assembly 14, and may generally include any suitable power source that enables the extracorporeal mechanical blood circulation support system 10 to function as described herein. Although the controller 20 and the power source are shown as being external to the blood pump assembly 14, in other embodiments, all or part of the controller 20 and / or the power source 22 may be incorporated into the blood pump assembly 14.

[0027] Figure 2 Is applicable to Figure 1 1 is a cutaway perspective view of an exemplary extracorporeal blood pump assembly 100 of a mechanical circulatory support system 10. The blood pump assembly 100 includes a blood pump 102 and an extracorporeal membrane oxygenator (ECMO) 104 fluidly connected to the blood pump 102. The blood pump assembly 100 includes an inlet 106 for receiving blood from the patient's circulatory system and an outlet 108 for returning blood to the patient's circulatory system. The inlet 106 and the outlet 108 can be connected using suitable fluid conduits (e.g., Figure 1 The fluid conduits 16, 18) shown in the figure are fluidly connected to the patient's blood circulation system, such as medical plastic tubing.

[0028] The blood pump assembly 100 is configured to pump blood from the patient's circulatory system so that the blood is received at the inlet 106, pumped through the ECMO 104 to increase the oxygen concentration in the blood and / or reduce the carbon dioxide concentration in the blood, and pumped back into the patient's circulatory system from the outlet 108. In the illustrated embodiment, the ECMO 104 is fluidly connected to the downstream of the blood pump 102 and defines the outlet 108, while the blood pump 102 defines the inlet 106. In other embodiments, the ECMO 104 can be fluidly connected to the upstream of the blood pump 102. In addition, in an exemplary embodiment, the ECMO 104 is removably connected to the blood pump 102. That is, the blood pump 102 and the ECMO 104 are connected together in a non-permanent manner to allow the blood pump 102 and the ECMO 104 to be repeatedly connected and disconnected without being damaged. The blood pump 102 and the ECMO 104 can be removably connected together by any suitable non-permanent connection method, for example, including but not limited to threads, crimp-type connectors, bayonet-type connectors, magnetic connectors, and combinations thereof. In other embodiments, ECMO 104 may be non-detachably connected to blood pump 102, for example by being integrally formed therewith.

[0029] The blood pump 102 includes a pump housing 110, which defines an inlet 112, an outlet 114, and a blood flow path 116 extending therebetween. The ECMO 104 includes a membrane housing 118, which defines an inlet 120, an outlet 122, and a blood flow path 124 extending therebetween. The two blood flow paths 116, 124 cooperate to form a blood flow path 126 of the blood pump assembly 100, which extends from the blood pump assembly inlet 106 to the blood pump assembly outlet 108.

[0030] In the illustrated embodiment, the pump housing 110 and the diaphragm housing 118 have a "colinear" configuration. That is, the respective inlets and outlets of the pump housing 110 and the diaphragm housing 118 are colinear with each other in the axial direction. More specifically, the pump housing 110 extends along a longitudinal axis 128, and each of the pump housing inlet 112 and the pump housing outlet 114 is coaxial with the pump housing longitudinal axis 128. Similarly, the diaphragm housing 118 extends along a longitudinal axis 130, and each of the diaphragm housing inlet 120 and the diaphragm housing outlet 122 is coaxial with the diaphragm housing longitudinal axis 130. In addition, the blood pump assembly inlet 106 and the blood pump assembly outlet 108 are also colinear with each other. In other embodiments, the pump housing 110 and / or the diaphragm housing 118 may have a configuration other than a colinear configuration. For example, Fig. 9 Is applicable to Figure 11 is a perspective view of another exemplary extracorporeal blood pump assembly 900 of the mechanical blood circulation support system 10, wherein the blood pump assembly 900 has a non-axial configuration. More specifically, the blood pump housing 110 of this embodiment defines a volute 902 located fluidically downstream of the pump rotor, which redirects blood flow in a direction perpendicular to the flow direction at the pump housing inlet 112. Fig. 9 As shown, the pump housing inlet 112 and outlet 114 are axially offset from each other, as are the inlet 106 and outlet 108 of the blood pump assembly 900. In addition, in this embodiment, the ECMO 104 is integrated with the pump housing outlet 114 to receive blood flow therefrom. In this embodiment, the axial blood flow through the ECMO 104 is in the azimuthal or primary azimuthal direction of the pump 102.

[0031] Reference again Figure 2 In the illustrated embodiment, the pump housing inlet 112 defines the inlet 106 of the blood pump assembly 100, and the membrane housing outlet 122 defines the outlet 108 of the blood pump assembly 100. In other embodiments, the pump housing outlet 114 may define the outlet 108 of the blood pump assembly 100, and the membrane housing inlet 120 may define the inlet 106 of the blood pump assembly 100. In operation, the blood pump 102 pumps blood from the respective inlets 112, 120 to the respective outlets 114, 122 through the blood flow paths 116, 124. In the illustrated embodiment, the membrane housing 118 may be connected to the blood pump 102 at the pump housing outlet 114. That is, the membrane housing inlet 120 is connected to the pump housing outlet 114. In other embodiments, the membrane housing 118 may be connected to the blood pump 102 at the pump housing inlet 112 (that is, the membrane housing outlet 122 may be connected to the pump housing inlet 112).

[0032] In the illustrated embodiment, the pump housing 110 includes a cylindrical body 132 and a fluid conduit connector 134 extending from the body 132. The fluid conduit connector 134 is suitable for (e.g., sized and shaped to) connect to a fluid conduit (e.g., fluid conduits 16, 18), such as a conventional medical tube for conveying blood. The fluid conduit connector 134 may have any suitable configuration (e.g., including but not limited to a Luer connector) that can achieve a leak-free or leak-proof connection between the pump housing 110 and the fluid conduit. In the illustrated embodiment, the pump housing 110 includes a single fluid conduit connector 134 that defines a pump housing inlet 112. In other embodiments, the pump housing 110 may include more than one fluid conduit connector 134 (e.g., one that defines a pump housing inlet 112 and one that defines a pump housing outlet 114), or a single fluid conduit connector 134 may be located at the pump housing outlet 114 and define the pump housing outlet 114.

[0033] In the illustrated embodiment, the membrane housing 118 also includes a fluid conduit connection 136 that defines the outlet 122 of the membrane housing 118. In other embodiments, the membrane housing 118 may include more than one fluid conduit connection 136 (e.g., one that defines the membrane housing inlet 120 and one that defines the membrane housing outlet 122), or a single fluid conduit connection 136 may be located at the membrane housing inlet 120 and define the membrane housing inlet 120.

[0034] Refer to Figure 3 , the body 132 of the pump housing 110 includes a radial inner wall 202, a radial outer wall 204 spaced radially outward from the radial inner wall 202, a first end wall 206 extending between the radial inner wall 202 and the radial outer wall 204 adjacent to the pump housing outlet 114, and a second end wall 208 extending between the radial inner wall 202 and the radial outer wall 204 adjacent to the pump housing inlet 112. The pump housing 110 defines an inner cavity 210 that is separated and sealed from the pump housing blood flow path 116 for accommodating electronics and other operating components of the blood pump 102. In the illustrated embodiment, the inner cavity 210 is defined by the radial inner wall 202, the radial outer wall 204, the first end wall 206, and the second end wall 208. The inner cavity 210 is separated from the blood flow path 116 by the radial inner wall 202.

[0035] The blood pump 102 also includes a stator 212 (in Figure 3 ), a rotor 214, and a flow conversion member 216. The stator 212 is located in the inner cavity 210, and the rotor 214 and the flow conversion member 216 are located in the pump housing blood flow path 116. The flow conversion member 216 is located downstream of the rotor 214 to convert the non-axial flow (i.e., the fluid flow mainly in the radial, azimuthal and / or circumferential directions) from the rotor 214 into an axial flow. The operation (e.g., rotation) of the rotor 214 causes the fluid (e.g., blood) to flow from the inlet 112 (e.g., Figure 2 114) flows through the blood flow path 116 to the outlet 114. The pump housing 110 defines a rotor chamber 218 along a portion of the blood flow path 116, in which the rotor 214 and the flow conversion member 216 are located. More specifically, the rotor chamber 218 includes an upstream portion 220 located near the pump housing inlet 112, and a downstream portion 222 located axially downstream of the upstream portion 220 and close to the pump housing outlet 114. The rotor 214 is located in the upstream portion 220 of the rotor chamber 218, and the flow conversion member 216 is located in the downstream portion 222 of the rotor chamber 218 axially downstream of the rotor 214.

[0036] The rotor 214 can rotate in response to the electromagnetic field generated by the stator 212 to pump blood from the pump housing inlet 112 to the pump housing outlet 114. The stator 212 and the rotor 214 can generally have any suitable configuration that enables the blood pump 102 to function as described herein. For example, the rotor 214 can be supported by one or more magnetic bearings, one or more mechanical bearings, or any combination of magnetic and mechanical bearings. Suitable embodiments of stators and rotors are described, for example, in U.S. Patent Nos. 7,798,952; 9,068,572; 9,091,271; and 9,265,870, which inventions are hereby incorporated by reference in their entirety. In some embodiments, the rotor 214 is a magnetically levitated rotor having a magnetically levitated configuration similar to the CentriMag commercially available from Abbott Laboratories. TM Construction used in acute circulatory support systems.

[0037] In the illustrated embodiment, the rotor 214 defines a central bore ( Figure 3 214, through which blood flows during operation of the blood pump 102. The rotor 214 includes impeller blades 224 and, in the illustrated embodiment, includes a shroud 226 that covers the downstream end of the impeller blades 224 adjacent to the flow switching member 216. In addition, in the illustrated embodiment, the rotor 214 includes a permanent magnet ( Figure 3 214). The permanent magnets have permanent north and south poles, which are used for combined active and passive magnetic suspension of the rotor 214 and for rotation of the rotor 214. In operation, the stator 212 is controlled to drive (i.e., rotate) the rotor and radially suspend the rotor 214 by generating an electromagnetic field that interacts with the permanent poles of the permanent magnets. In this way, the stator 212 acts as an active magnetic bearing.

[0038] The stator 212 generally includes a plurality of winding structures that generate a suitable electromagnetic field that interacts with the rotor 214 to rotate and levitate the rotor 214. In the illustrated embodiment, the stator 212 includes a plurality of pole pieces 228 ( Figure 3 228). The blood pump assembly 100 may include any suitable number of pole pieces that enable the blood pump assembly 100 to function as described herein. In some embodiments, the blood pump assembly 100 includes six pole pieces 228. In some embodiments, the blood pump assembly 100 may include more than six or less than six pole pieces, such as four pole pieces or eight pole pieces. However, in other embodiments, the blood pump assembly 100 may include less than four pole pieces, or more than eight pole pieces. In the illustrated embodiment, each pole piece 228 includes a drive coil 230 for generating an electromagnetic field to rotate the rotor 214, and a suspension coil 232 for generating an electromagnetic field to control the radial position of the rotor 214.

[0039] Each of the drive coil 230 and the suspension coil 232 includes a plurality of conductor windings wound around the pole piece 228. The drive coil 230 and the suspension coil 232 of the stator 212 are arranged in opposing pairs, and control the drive of the rotor 214 and radially levitate the rotor 214 by generating an electromagnetic field that interacts with the permanent magnetic poles of the permanent magnets. Although in the illustrated embodiment, the drive coil 230 and the suspension coil 232 are shown as separate coils, it should be understood that the drive coil 230 and the suspension coil 232 can be implemented as a single coil that is configured to generate an electromagnetic field for the rotation and radial suspension of the rotor 214. For example, suitable methods for controlling the stator 212 and for generating an electromagnetic field to rotate and radially levitate the rotor 214 are described in U.S. Patents 8,770,945; 9,068,572; and 9,849,224, the contents of which are incorporated herein by reference in their entirety. The stator 212 may be communicatively coupled to a suitable controller, such as the controller 20 , to control the current supplied to the stator 212 to generate an electromagnetic field to rotate and radially levitate the rotor 214 .

[0040] In the illustrated embodiment, the flow converter 216 is axially located downstream of the rotor 214 and is configured to convert the non-axial blood flow from the rotor 214 into an axial blood flow toward the pump housing outlet 114. The flow converter 216 may generally include any suitable structure for converting the non-axial blood flow into the axial blood flow, which may include, for example, but not limited to, stator blades, diffusers, volutes, and combinations thereof. In an exemplary embodiment, the flow converter 216 includes a plurality of stator blades 234 extending radially outward from a central hub 236. Figure 3 As shown, the stator blades 234 and the central hub 236 are located fluidically and axially downstream of the rotor 214. Each stator blade 234 extends from a leading edge 238 to a trailing edge 240 along a path that gradually transitions from a primarily circumferential orientation to a primarily axial orientation. That is, each stator blade 234 extends from the leading edge 238 in a direction having a circumferential component and an axial component, wherein the circumferential component gradually and continuously decreases as the stator blade 234 extends toward the trailing edge 240 until the stator blade 234 is substantially oriented in the axial direction. Therefore, the trailing edge 240 of each stator blade 234 is circumferentially offset from the leading edge 238 by a certain angle. In the illustrated embodiment, the trailing edge 240 of each stator blade 234 is circumferentially offset from the leading edge 238 by an angle of approximately 30°. In other embodiments, the trailing edge 240 of each stator blade 234 is circumferentially offset from the leading edge 238 by an angle less than or greater than 30°, such as 15°, 45°, 60°, 75°, or 90°.

[0041] In some embodiments, one or more stator blades 234 may include a stator blade extension 242 that extends axially upstream of a downstream end of rotor 214 (e.g., shroud 226) such that stator blade extension 242 axially overlaps rotor 214. Stator blade extension 242 may facilitate conversion of non-axial flow from rotor 214 to axial flow through flow converter 216. Figure 3 2 is shown in phantom in FIG. 2 , although the plurality of stator blades 234 may include more than one stator blade extension 242 . In some embodiments, for example, each of the plurality of stator blades 234 includes a stator blade extension 242 .

[0042] In some embodiments, the flow conversion member 216 can be removably connected to the pump housing 110, for example, to facilitate cleaning of the flow conversion member 216 and / or the pump housing 110 so that the blood pump 102 can be reused. For example, the stator blades 234 and the hub 236 can be connected to the pump housing 110 by friction fit or compression. Additionally or alternatively, the blood pump 102 can include one or more retaining rings ( Figure 3 ) to secure the stator blades 234 and the hub 236 in place. In other embodiments, the flow converter 216 is attached to the ECMO 104 (e.g., the membrane housing 118) and inserted into the rotor cavity 218 when the membrane housing 118 is connected to the pump housing 110. In such embodiments, the flow converter 216 can be discarded when the ECMO 104 is replaced or discarded. In other embodiments, the flow converter 216 can be connected to the pump housing 110 using any suitable non-permanent connection method that allows the flow converter 216 and the pump housing 110 to be repeatedly connected and separated without damage, such as but not limited to threads, bayonet connectors, magnetic connectors, and combinations thereof. In other embodiments, the flow converter 216 can be non-detachably connected to the pump housing 110. In some embodiments, for example, the stator blades 234 and the hub 236 can be integrally formed with the pump housing 110 (e.g., by additive manufacturing).

[0043] The blood pump assembly 100 also includes a heat exchanger 244 thermally coupled to the flow converter 216 to heat and / or cool the blood flowing through the blood pump assembly 100. The heat exchanger 244 may generally include any suitable heating and / or cooling element capable of exchanging heat with the blood flowing through the blood pump assembly 100, including, for example, but not limited to, resistive (e.g., electric) heaters, thermoelectric coolers (e.g., Peltier coolers), and fluid heat exchangers (e.g., heated or cooled water pumped through a tube in fluid communication with the plurality of stator blades 234). Figure 3In the illustrated embodiment, the heat exchanger 244 is disposed within the inner cavity 210 and extends circumferentially around the plurality of stator blades 234. The heat exchanger 244 is thermally connected to the plurality of stator blades 234 via the radial inner wall 202 of the main body 132, so that heat is transferred between the heat exchanger 244 and the plurality of stator blades 234 via the radial inner wall 202. In such embodiments, the main body 132 may be constructed of a suitable thermally conductive material to facilitate heat exchange between the heat exchanger 244 and the plurality of stator blades 234. Suitable thermally conductive materials include, but are not limited to, metals, metal alloys, aluminum, titanium, steel, stainless steel, copper, brass, bronze, beryllium, any alloy combination thereof, and thermally conductive ceramics, such as alumina. Figure 3 , the heat exchanger 244 is shown as being located proximate to the flow transition member 216 and extending a length that is substantially equal to the axial length of the flow transition member 216. In other embodiments, the heat exchanger 244 may extend axially beyond the flow transition member 216 and / or may be located at a location within the inner cavity 210 other than proximate to the flow transition member 216. In some embodiments, for example, the heat exchanger 244 or a component thereof is located adjacent to the upstream portion 220 of the rotor cavity 218 to achieve heat transfer adjacent to the rotor 214. Further, in some embodiments, the heat exchanger 244 may be partially or fully integrated with the radial inner wall 202. For example, the heat exchanger 244 may include one or more resistive heating coils that are molded, cast, embedded, or otherwise integrated into the radial inner wall 202. Additionally or alternatively, the heat exchanger 244 may include a fluid passage defined by the radial inner wall 202 for a heat exchange fluid to flow therethrough.

[0044] Figure 4 Schematically shows Figure 3 The flow transition member 216 is coupled to another suitable embodiment of a heat exchanger 300 that is thermally coupled to the flow transition member 216 . Figure 4 The heat exchanger 300 shown in FIG. Figure 3 In this embodiment, the heat exchanger 300 is disposed in the central hub 236 and a plurality of stator blades 234 ( Figure 4More specifically, in the present embodiment, the heat exchanger 300 is a resistive heater, comprising at least one wire 302 that passes through the central hub 236 and at least one of the plurality of stator blades 234. The wire 302 is coupled to a suitable power source (e.g., the power source 22) for supplying power to the wire 302. The heat generated by the wire 302 through resistive heating is transferred to the blood flowing through the blood pump assembly 100 through the stator blades 234 and the central hub 236. In other embodiments, the heat exchanger 300 may not be disposed in the plurality of stator blades 234, but may instead be disposed within the central hub 236. In such embodiments, heat exchange with the blood flowing through the blood pump assembly 100 may occur through the central hub 236 and / or through the plurality of stator blades 234, because the stator blades 234 are coupled to the central hub 236 in thermal communication. For example, heat generated within the central hub (eg, heat generated by the electrical wires 302 ) may be thermally transferred to the plurality of stator blades 234 via conduction, and then transferred to the blood via the stator blades 234 .

[0045] The blood pump 102 may include other components in addition to those described above, including, for example, but not limited to, an onboard controller and one or more sensors 246 for detecting blood flow characteristics through the blood pump 102. In some embodiments, for example, the onboard or stand-alone controller is implemented as a printed circuit board (PCB) located within the inner cavity 210. Figure 3 244) and is in communication with one or more sensors 246 to control the operation of one or more components of the blood pump 102, such as the rotor 214 and the heat exchanger 244. The sensors 246 may include, but are not limited to, pressure sensors, flow (volume and / or mass) sensors, and temperature sensors. Figure 3 A single sensor 246 is shown at the inlet 112 of the pump housing 110, but it should be understood that the blood pump 102 may include any suitable number of sensors located at any suitable location that enables the blood pump assembly 100 to function as described herein. In some embodiments, for example, the blood pump assembly 100 may include a sensor 246 located at the pump housing inlet 112, the pump housing outlet 114, the diaphragm housing inlet 120, the diaphragm housing outlet 122, and / or located at any location between the inlet 106 of the blood pump assembly 100 including the inlet 106 and the outlet 108 of the blood pump assembly 100.

[0046] Refer to Figure 5, ECMO 104 includes an oxygenator membrane 402 to increase the oxygen concentration and / or reduce the carbon dioxide concentration of the blood pumped through the blood pump assembly 100. The oxygenator membrane 402 is disposed within the blood flow path 124 defined by the membrane housing 118, such that the blood flowing through the ECMO 104 flows through and contacts the oxygenator membrane 402. The oxygenator membrane 402 may generally include any suitable oxygenator membrane that enables the blood pump assembly 100 to function as described herein, including, for example, and without limitation, fiber bundles, porous media, laminated plates, microfluidic channels, bubble oxygenation, and artificial organs (e.g., lungs).

[0047] In the illustrated embodiment, the oxygenator membrane 402 is a fiber bundle that includes a plurality (e.g., thousands) of fibers 404, each of which is configured to exchange gases with blood in contact therewith. In some embodiments, for example, the fibers 404 are hollow, microporous fibers that allow gas exchange with blood through micropores in the fibers. More specifically, each fiber defines an internal channel that communicates with a gas source (e.g., oxygen and / or an oxygen-enriched gas mixture) and allows gas exchange between the gas in the internal channel and the blood in contact with the fiber through micropores on the fiber surface. In other embodiments, the fibers 404 may be coated or skinned fibers that allow oxygen and / or carbon dioxide to diffuse through a non-porous skin layer on the outer surface of the fiber. The ends of the fibers 404 and / or the fiber bundle may be cast (e.g., with a polymer such as polyurethane). Additionally, the ends of the fibers may be trimmed, cut, or otherwise opened to allow communication between the internal channels of the hollow fibers and the gas source. Suitable fibers 404 for use in the oxygenator membrane 402 include, for example, but are not limited to, commercially available fibers having an outer diameter in the range of 200 to 400 microns and a wall thickness in the range of 20 to 50 microns.

[0048] In the illustrated embodiment, gas is supplied to the end of the fiber 404 through the cavity 406 defined in the membrane shell 118. More specifically, the membrane shell 118 is a double-walled shell, which includes an inner wall 408 and an outer wall 410, which cooperate to define the cavity 406. The cavity 406 is divided into a gas supply section and a ventilation section. The gas supply section is connected to a suitable gas source (e.g., oxygen and / or oxygen-enriched mixed gas), which is supplied to the fiber 404 for gas exchange with the blood in contact therewith. The gas source may include, for example, but is not limited to, ambient atmosphere, compressed air and oxygen. The ventilation section may be open to the atmosphere, or connected to a suitable rebreather system, so as to facilitate gas absorption from the gas source through the fiber 404. The first end of each fiber 404 is arranged in the gas supply section of the cavity 406, and the second end of each fiber 404, i.e., the opposite end, is arranged in the ventilation section of the cavity 406 to allow gas from the gas source to flow from the gas supply section to the ventilation section through each fiber 404.

[0049] In the illustrated embodiment, the fibers 404 of the fiber bundle are oriented perpendicular to the direction of blood flow, which is represented by the blood flow path 124, and perpendicular to the longitudinal axis 130 of the membrane shell 118. In other embodiments, the direction of the fibers 404 may be oriented in a direction that is not perpendicular to the direction of blood flow and / or the longitudinal axis 130 of the membrane shell 118. In some embodiments, for example, the fibers 404 are oriented parallel to the direction of blood flow and / or the longitudinal axis 130 of the membrane shell 118. In other embodiments, the fibers 404 may be oriented at an oblique angle relative to the direction of blood flow and / or the longitudinal axis 130 of the membrane shell 118. In other embodiments, the fibers 404 may have a multi-directional orientation. That is, the fiber bundle may include multiple groups of fibers 404, each group of fibers being oriented at a different angle. For example, Figure 6 An ECMO 104 having an oxygenator membrane 502 is shown that includes a fiber bundle having a multi-directional orientation. In the illustrated embodiment, the fiber bundle includes two groups of fibers, each group of fibers being oriented at an angle of approximately 45° relative to the direction of blood flow and the longitudinal axis 130 of the membrane shell 118. Without being bound by any particular theory, it is believed that such fiber bundle orientation can facilitate reducing or disrupting microscopic flow patterns in the blood flow through the membrane shell 118, and thereby facilitate improved oxygen and / or carbon dioxide transfer between the fibers 404 and the blood flowing through the ECMO 104.

[0050] Reference again Figure 5 , the membrane housing 118 includes a first section 412 having a first cross-sectional area, a second section 414 having a smaller cross-sectional area than the first, and a third narrowing section 416 having a narrowed cross-section disposed between the first section 412 and the second section 414. In the illustrated embodiment, the membrane housing 118 is generally cylindrical. More specifically, the first section 412 and the second section 414 are cylindrical, and the third narrowing section 416 is conical. Therefore, in the illustrated embodiment, the first section 412 of the membrane housing has a first diameter, the second section 414 of the membrane housing 118 has a second diameter that is smaller than the first diameter, and the narrowing section 416 has a diameter that transitions from the first diameter to the second diameter. In the illustrated embodiment, the narrowing section 416 is located downstream of the first section 412 of the membrane housing 118, although in other embodiments, the narrowing section 416 may be located upstream of the first section 412 of the membrane housing 118.

[0051] The oxygenator membrane 402 is disposed in the first section 412 and is generally sized and shaped to be complementary to the inner surface of the membrane housing 118. In the illustrated embodiment, the oxygenator membrane 402 extends into the narrowed section 416. Thus, in the illustrated embodiment, the oxygenator membrane 402 includes a first section 418 having a constant cross-sectional area or diameter, and a second section 420 having a narrowed cross-sectional area or diameter. In the illustrated embodiment, the fibers 404 in the fiber bundle are oriented perpendicular to the direction of blood flow and the longitudinal axis 130 of the membrane housing 118. Thus, the fibers 404 located within the membrane housing narrowed section 416 have a shorter length than the fibers 404 located outside the membrane housing narrowed section 416 (i.e., the fibers 404 located within the membrane housing first section 412). Without being bound by any particular theory, it is believed that the fibers 404 located within the second, narrowed section 420 of the oxygenator membrane 402, particularly fibers oriented perpendicular to or at an angle to the direction of blood flow and the longitudinal axis of the membrane shell 118, can exhibit better carbon dioxide transfer (i.e., clearance) from the blood because the fibers 404 in the second narrowed section 420 have a smaller length and, therefore, a lower carbon dioxide partial pressure across their entire length than the other fibers 404 in the fiber bundle. Thus, the ECMO of the present invention can optimize oxygen delivery and carbon dioxide transfer.

[0052] ECMO 104 can have any suitable size and volume that enables blood pump assembly 100 to function as described herein. In some embodiments, the size of ECMO 104 is selected based on the characteristics of the patient for whom blood pump assembly 100 is used. For example, a larger ECMO 104 can be used for adult patients, while a smaller ECMO 600 (e.g., Figure 7 104) can be used for children or young children. Additionally or alternatively, the size and shape of ECMO 104 can be designed for optimal gas exchange characteristics. For example, an ECMO optimized for removing carbon dioxide (i.e., relatively long and narrow) can be used for patients who need enhanced removal of carbon dioxide in the blood. In addition, ECMO 104 is interchangeable with ECMOs of different sizes, such as ECMOs with oxygenator membranes having different oxygen and / or carbon dioxide gas exchange capabilities. In some embodiments, ECMO 104 is one of a plurality of ECMOs configured for use with blood pump 102. That is, ECMO 104 can be part of a kit including blood pump 102 and a plurality of ECMOs (e.g., ECMO 104 and ECMO 600), each of which is interchangeable with another and removably connected to blood pump 102. ECMOs may have different sizes, volumes, and / or gas exchange characteristics.

[0053] As described above, the ECMO 104 and oxygenator membrane 402 in the illustrated embodiment have circular cross-sections. In other embodiments, the ECMO 104 and oxygenator membrane 402 may have cross-sections other than circular cross-sections. For example, in some embodiments, the ECMO 104 and oxygenator membrane 402 may have rectangular cross-sections. In such embodiments, blood flow through the blood pump assembly 100 will transition from a circular cross-section (i.e., within the pump housing 110) to a rectangular cross-section (i.e., within the membrane housing 118).

[0054] Figure 8 yes Figure 2 1 is a perspective view of a blood pump assembly 100 having an ECMO 802 having a rectangular cross-section. More specifically, Figure 8 The ECMO 802 includes a membrane shell 804, which includes a first section 806 with a rectangular cross-section, a second section 808 with a circular cross-section, and a third narrowing section 810 with a pyramidal cross-section arranged between the first section 806 and the second section 808. The first section 806 of the membrane shell has a larger cross-sectional area than the second section 808 of the membrane shell, and the third section 810 of the membrane shell has a gradually decreasing narrowing cross-section. In this embodiment, the first section 806 of the membrane shell defines the inlet ( Figure 8 ), and the membrane shell second section 414 defines the outlet 812 of the ECMO 802.

[0055] In this embodiment, the oxygenator membrane ( Figure 8 More specifically, the oxygenator membrane is part of a membrane cassette 814 that can be inserted into and removed from the membrane housing 804 when the membrane housing 804 is connected to the blood pump housing 110. In other words, the membrane cassette 814 including the oxygenator membrane disposed therein can be inserted into and / or removed from the membrane housing 804 without disconnecting the membrane housing 804 from the blood pump housing 110. The membrane cassette 814 can be inserted into and removed from the membrane housing 804 in a direction perpendicular to the direction of blood flow (indicated by arrow 816) and can also be inserted into and removed in a direction perpendicular to the direction of gas flow through the fibers of the oxygenator membrane. In the illustrated embodiment, for example, blood flows through the blood pump assembly 100 in a first direction indicated by arrow 818, and gas flows through the fibers of the oxygenator membrane in a second direction perpendicular to the first direction indicated by arrow 820. The membrane cassette 814 can be inserted into and removed from the membrane housing 804 along a third direction 816 that is perpendicular to both the first direction 818 and the second direction 820 .

[0056] In some embodiments, ECMO 802 may include one or more mechanical guides 822 to facilitate the insertion and / or removal of the membrane cassette 814. Suitable mechanical guides 822 include, for example, but are not limited to, guide rails, plates, and combinations thereof. In the illustrated embodiment, the mechanical guides 822 include an upper plate 824 and a lower plate 826 connected to the membrane shell 804. The upper plate 824 and the lower plate 826 extend from the membrane shell 804 to facilitate the insertion of the membrane cassette 814 into the membrane shell 804. The upper plate 824 and the lower plate 826 may be hingedly connected to the membrane shell 804 to allow the plates to be folded into a folded configuration (i.e., against the membrane shell 804) when not in use.

[0057] Additionally, in some embodiments, the membrane cassette 814 may be pre-filled (i.e., filled with liquid) before being inserted into the membrane shell 804. The mechanical guide 822 for guiding the membrane cassette 814 into the membrane shell 804 may be configured to prevent fluid from leaking from the pre-filled membrane cassette 814. In the illustrated embodiment, for example, the upper plate 824 covers the outlet of the membrane cassette 814, and the lower plate 826 covers the inlet of the membrane cassette 814, thereby preventing fluid from leaking from the membrane cassette 814. In addition, in some embodiments, the fluid inlet and / or outlet may be integrated in the mechanical guide 822 to achieve pre-filling of the membrane cassette 814. In the illustrated embodiment, for example, the lower plate 826 may include a fluid supply port, which is fluidically connected to the fluid inlet of the membrane cassette 814 to supply fluid to the membrane cassette 814 before inserting the membrane shell 804. The upper plate 824 may include a fluid outlet, a return line, and / or a vent to facilitate pumping fluid through the membrane cassette 814 to pre-fill the membrane cassette 814.

[0058] Reference again Figure 2, when the membrane housing 118 and the pump housing 110 are connected together, they define a continuous blood flow path having a substantially constant cross-sectional area or diameter. More specifically, the membrane housing 118 is connected to the pump housing 110 at an interface 248, and the blood flow path 126 of the blood pump assembly 100 extends through the interface. The cross-sectional area of ​​the blood flow path 126 across the interface 248 is substantially constant. For example, in the illustrated embodiment, the cross-sectional area of ​​the blood flow path 126 upstream of the interface 248 (i.e., the portion of the blood flow path 126 defined by the pump housing 110) is equal to the cross-sectional area of ​​the blood flow path 126 downstream of the interface 248 (i.e., the portion of the blood flow path 126 defined by the membrane housing 118). Stated another way, the cross-sectional area of ​​the membrane housing first section 412 is substantially equal to the cross-sectional area of ​​the rotor cavity 218. In other embodiments, the cross-sectional area of ​​the blood flow path 126 across the interface varies by less than 20%, less than 10%, less than 5%, or even less than 2%. Additionally, the blood flow path 126 of the blood pump assembly 100 may be free of turns and bends to reduce shear stress and / or hemolysis of the blood flowing through the blood pump assembly 100. In the illustrated embodiment, for example, the inlet 106 and the outlet 108 of the blood pump assembly are axially co-linear with each other, and the blood flow path 126 of the blood pump assembly 100 is free of turns and bends.

[0059] As described herein, the blood pump assembly of the present invention provides several advantages compared to previous designs of extracorporeal blood pumps. For example, compared to a single or independent blood pump and ECMO module, the blood pump assembly of the present invention is advantageous in reducing the drop in blood pressure by providing a blood flow path without bends and turns and having a substantially constant cross-sectional area through the blood pump and ECMO. This reduces or eliminates the nozzle / throat effect otherwise produced by connecting the independent blood pump and ECMO module with a pipe fitting, and also avoids unnecessary bends and twists in the blood flow path. An embodiment of the blood pump assembly may also be free of a volute, which may otherwise result in a nozzle / throat effect, a longer than necessary blood flow path (and associated pressure drops and greater priming), and at least one additional bend in the blood flow path. The blood pump assembly of the present invention is also advantageous in reducing the priming amount of the unit, for example, by eliminating the tube between the blood pump and the ECMO module, and providing modularity for ECMO modules of different sizes (for example, ECMO modules with different priming amounts for adult and pediatric modules can be interchanged as needed). The modularity of the blood pump assembly also allows the replacement or discarding of the ECMO oxygenator membrane without having to discard the blood pump, so that the blood pump can be cleaned and reused. Embodiments of the blood pump assembly may also include an integrated heat exchanger, thereby eliminating the need for a separate heat exchanger and associated fluid lines (eg, connecting a separate water heater / cooler).

[0060] Although the embodiments and examples disclosed in the present invention have been described with reference to specific embodiments, it should be understood that these embodiments and examples are merely illustrative of the principles and applications of the present invention. Therefore, it should be understood that various modifications may be made to the illustrative embodiments and examples, and other arrangements may be designed without departing from the spirit and scope of the present invention as defined in the claims. Therefore, this application is intended to cover modifications and variations of these embodiments and their equivalents.

[0061] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any device or system and performing any incorporated method. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. If these examples have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims, then these other examples are within the scope of the claims.

Claims

1. An extracorporeal blood pump assembly, comprising: A blood pump comprising a pump housing, a rotor, and a flow conversion member located downstream of the rotor for converting non-axial flow from the rotor into axial flow, the pump housing defining an inlet and an outlet; and An extracorporeal membrane oxygenator (ECMO) comprising a membrane housing and an oxygenator membrane disposed within the membrane housing, wherein the membrane housing is detachably connected to the pump housing at one of the pump housing inlet and the pump housing outlet, wherein a blood pump housing and the membrane housing cooperate to define a blood flow path extending from the inlet of the blood pump assembly to the outlet of the blood pump assembly, wherein the pump housing is connected to the membrane housing at an interface, wherein a cross-sectional area of ​​the blood flow path across the interface is substantially constant.

2. The extracorporeal blood pump assembly of claim 1, wherein the blood flow path is free of bends and turns.

3. The extracorporeal blood pump assembly of claim 1, wherein the inlet and the outlet of the blood pump assembly are axially collinear with each other.

4. The extracorporeal blood pump assembly of claim 1, wherein the cross-sectional area of ​​the blood flow path across the interface varies by less than 20%.

5. An extracorporeal blood pump assembly according to claim 1, wherein the pump housing defines a cavity, the cavity including an upstream portion and a downstream portion axially downstream of the upstream portion, wherein the rotor is located in the upstream portion and the flow conversion element is located in the downstream portion.

6. The extracorporeal blood pump assembly of claim 1, wherein the flow converter comprises a plurality of stator blades located fluidically downstream of the rotor.

7. An extracorporeal blood pump assembly according to claim 6, wherein at least one of the plurality of stator blades includes a stator blade extension, which extends axially upstream of the downstream end of the rotor so that the stator blade extension is axially overlapped with the rotor.

8. The extracorporeal blood pump assembly of claim 6, further comprising a heat exchanger, wherein the heat exchanger is at least one of coupled in thermal communication with the plurality of stator blades or disposed within at least one of the plurality of stator blades.

9. The extracorporeal blood pump assembly of claim 8, wherein each of the plurality of stator blades extends radially outward from a rotating hub, and wherein the heat exchanger is disposed within the rotating hub.

10. The extracorporeal blood pump assembly of claim 8, wherein the heat exchanger is disposed within at least one of the plurality of stator blades.

11. The extracorporeal blood pump assembly of claim 8, wherein the heat exchanger comprises at least one of a resistive heater and a thermoelectric cooler.

12. The extracorporeal blood pump assembly according to claim 1, wherein the membrane housing comprises a first section having a first cross-sectional area, a second section having a second cross-sectional area smaller than the first section, and a narrowing section arranged between the first section and the second section and having a narrowed cross-sectional area, wherein the oxygenator membrane is disposed in the first section and extends into the narrowing section.

13. The extracorporeal blood pump assembly of claim 12, wherein the oxygenator membrane comprises a plurality of fibers, wherein the fibers located within the constriction section are shorter in length than the fibers located outside the constriction section.

14. The extracorporeal blood pump assembly of claim 1 , wherein the extracorporeal membrane oxygenator further comprises a membrane cassette, wherein the oxygenator membrane is disposed within the membrane cassette, wherein the membrane cassette is insertable into and removable from the membrane housing when the pump housing is connected to the membrane housing.

15. An extracorporeal blood pump assembly kit, comprising A blood pump comprising a pump housing, a rotor, and a flow conversion member located downstream of the rotor for converting non-axial flow from the rotor into axial flow, the pump housing defining an inlet and an outlet; a first extracorporeal membrane oxygenator (ECMO) removably connectable to one of the pump housing inlet and the pump housing outlet at an interface, wherein a cross-sectional area of ​​a blood flow path across the interface is substantially constant; and and a second extracorporeal membrane oxygenator detachably connectable to one of the pump housing inlet and the pump housing outlet to enable the first extracorporeal membrane oxygenator to be interchangeable with the second extracorporeal membrane oxygenator, wherein the second extracorporeal membrane oxygenator has at least one of a size, a volume, and a gas exchange characteristic that is different from that of the first extracorporeal membrane oxygenator. 16 . The extracorporeal blood pump assembly kit according to claim 15 , wherein each of the first extracorporeal membrane oxygenator and the second extracorporeal membrane oxygenator comprises a membrane housing and an oxygenator membrane disposed within the membrane housing.

17. A method for assembling an extracorporeal blood pump assembly, comprising: Providing a blood pump comprising a pump housing, a rotor, and a flow conversion member located downstream of the rotor to convert non-axial flow from the rotor into axial flow, wherein the pump housing defines an inlet and an outlet; An extracorporeal membrane oxygenator (ECMO) is provided, comprising a membrane shell and an oxygenator membrane disposed in the membrane shell; and The membrane housing is removably connected to the pump housing at one of the pump housing inlet and the pump housing outlet, wherein the blood pump housing and the membrane housing cooperate to define a blood flow path extending from the inlet of the blood pump assembly to the outlet of the blood pump assembly, wherein the pump housing is connected to the membrane housing at an interface, wherein a cross-sectional area of ​​the blood flow path across the interface is substantially constant.

18. The method of claim 17, wherein the extracorporeal membrane oxygenator is a first extracorporeal membrane oxygenator, the method further comprising: Disconnecting the membrane housing from the pump housing; as well as A second extracorporeal membrane oxygenator is removably connected to the pump housing at one of the pump housing inlet and the pump housing outlet, wherein the second extracorporeal membrane oxygenator has at least one of a size, a volume, and a gas exchange characteristic that is different from the first extracorporeal membrane oxygenator.

19. The method of claim 17, wherein the membrane housing defines an inlet and an outlet, the method further comprising: connecting a first fluid conduit to one of the pump casing inlet and the pump casing outlet; as well as A second fluid conduit is connected to one of the membrane housing inlet and the membrane housing outlet.

Images