Integrated centrifugal blood pump-oxygenator, an extracorporeal life support system and a method of de-bubbling and priming an extracorporeal life support system

• US 10,258,729 B2
• Filed: 01/28/2016
• Issued: 04/16/2019
• Est. Priority Date: 12/07/2006
• Status: Active Grant

• Current Assignee: Thoratec LLC, University of Maryland Baltimore County (University of Maryland)
• Original Assignee: Thoratec LLC, University of Maryland Baltimore County (University of Maryland)
• Inventors: Gellman, Barry N., Koert, Andrew, Wu, Zhongjun, Zhang, Juntao, Griffith, Bartley P.
• Primary Examiner(s): Deak, Leslie R
• Application Number:
  US15/009,702
• Publication Number:
  US 20170021081A1
• Time in Patent Office: 1,174 Days
• Field of Search: 422 44- 48, 604 401, 604 609, 604 611, 604 613, 604 614
• CPC Class Codes: A61M 1/1698 Blood oxygenators with or without heat-exchangers intracorporal A61M1/1678; manufacturing of membranes therefor B01D67/00; semi-permeable membranes for separation processes characterised by their properties B01D69/00; semi-permeable membranes characterised by their material B01D71/00
• CPC Class Codes: A61M 1/262 rotating
• CPC Class Codes: A61M 1/267 used for pumping
• CPC Class Codes: A61M 1/3623 Means for actively controlling temperature of blood
• CPC Class Codes: A61M 2205/33 Controlling, regulating or measuring
• CPC Class Codes: A61M 2205/3303 Using a biosensor
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 60/113 in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/232 Centrifugal pumps
• CPC Class Codes: A61M 60/38 Blood oxygenation
• CPC Class Codes: A61M 60/419 the force acting on the blood contacting member being permanent magnetic, e.g. from a rotating magnetic coupling between driving and driven magnets
• CPC Class Codes: A61M 60/422 the force acting on the blood contacting member being electromagnetic, e.g. using canned motor pumps
• CPC Class Codes: A61M 60/508 Electronic control means, e.g. for feedback regulation
• CPC Class Codes: A61M 60/851 Valves

Abstract

A method for pumping and oxygenating blood includes receiving a flow of gas including oxygen into a gas inlet manifold via a gas inlet. The flow of gas is passed through the hollow fibers from the gas inlet manifold to a gas outlet manifold. The flow of gas is output from the gas outlet manifold via a gas outlet. An impeller is rotated to generate a flow of blood that flows over the hollow fibers. Oxygen from the flow of gas is transferred to the flow of blood through the hollow fibers. Carbon dioxide is transferred from the flow of blood to the flow of gas through the hollow fibers.

Claims

1. A method for pumping and oxygenating blood, the method including:

receiving a flow of gas including oxygen into a gas inlet manifold via a gas inlet of a housing in which the gas inlet manifold is disposed;

passing the flow of gas from the gas inlet manifold to a gas outlet manifold disposed within the housing through an oxygenator assembly having an exterior surface and an interior surface forming an exterior surface of a blood outlet channel, the oxygenator assembly including a plurality of hollow fibers through which the gas outlet manifold is in fluid communication with the gas inlet manifold, the blood outlet channel being coaxial with the oxygenator assembly;

outputting the flow of gas from the gas outlet manifold via a gas outlet of the housing;

rotating an impeller to generate a flow of blood that flows through a blood inlet to a blood inlet channel, through the blood inlet channel to the exterior surface of the oxygenator assembly, from the exterior surface of the oxygenator assembly through the oxygenator assembly and the interior surface of the oxygenator assembly into the blood outlet channel, and through the blood outlet channel to a blood outlet;

transferring oxygen from the flow of gas to the flow of blood through the hollow fibers; and

transferring carbon dioxide from the flow of blood to the flow of gas through the hollow fibers.

2. The method of claim 1, wherein each of the plurality of hollow fibers have substantially the same effective length so that the flow of gas flows through each of the plurality of hollow fibers the same rate.

3. The method of claim 1, comprising passing the flow of gas through the plurality of hollow fibers at a pressure less than a pressure of the flow of blood passing through the oxygenator assembly to inhibit formation of gaseous emboli in the flow of blood.

4. The method of claim 3, wherein:

the gas outlet manifold is disposed below the plurality of hollow fibers so that blood entering into one or more of the plurality of hollow fibers drains into the gas outlet manifold; and

the gas outlet is disposed below the gas outlet manifold so that blood draining into the gas outlet manifold drains out through the gas outlet.

5. The method of claim 1, wherein the plurality of hollow fibers are oriented in a cross-biased arrangement.

6. The method of claim 1, wherein the plurality of hollow fibers are arranged so that a packing ratio of a total cross-sectional area of the plurality of hollow fibers to a total cross-sectional area of a oxygenator membrane formed by the plurality of hollow fibers is between 0.10 to 0.55.

7. The method of claim 6, wherein the packing ratio is between 0.15 and 0.45.

8. The method of claim 7, wherein the packing ratio is between 0.15 and 0.45.

9. The method of claim 1, wherein the plurality of hollow fibers are arranged circumferentially around the blood outlet channel.

10. The method of claim 9, wherein the blood inlet channel is surrounded by the blood outlet channel.

11. The method of claim 1, wherein the plurality of hollow fibers is coated with an anti-thrombogenic agent.

12. The method of claim 1, comprising magnetically suspending the impeller in a contact-free manner with respect to the housing during rotation of the impeller.

13. The method of claim 1, comprising the flowing the flow of blood through a frustoconical manifold to rotating outwardly radiating blades of the impeller.

14. The method of claim 13, comprising converting rotational flow velocity of the flow of blood into a pressure increase in the flow of blood via diffuser fins disposed downstream of the impeller.

15. The method of claim 1, comprising recirculating a subset of the flow of blood from the blood outlet channel to the blood inlet channel.

16. The method of claim 15, comprising repositioning a valve to change a flow rate of blood recirculated from the blood outlet channel to the blood inlet channel.

17. The method of claim 1, wherein the impeller is rotated within the housing.

18. A method for pumping and oxygenating blood, the method including:

receiving a flow of gas including oxygen into a gas inlet manifold via a gas inlet of a housing in which the gas inlet manifold is disposed;

passing the flow of gas from the gas inlet manifold to a gas outlet manifold disposed within the housing through an oxygenator assembly having an exterior surface and an interior surface forming an exterior surface of a blood outlet channel, the oxygenator assembly including a plurality of hollow fibers through which the gas outlet manifold is in fluid communication with the gas inlet manifold;

outputting the flow of gas from the gas outlet manifold via a gas outlet of the housing;

magnetically suspending an impeller in a contact-free manner with respect to the housing during rotation of the impeller;

rotating the impeller to generate a flow of blood that flows through a blood inlet to a blood inlet channel, through the blood inlet channel to the exterior surface of the oxygenator assembly, from the exterior surface of the oxygenator assembly through the oxygenator assembly and the interior surface of the oxygenator assembly into the blood outlet channel, and through the blood outlet channel to a blood outlet;

transferring oxygen from the flow of gas to the flow of blood through the hollow fibers; and

transferring carbon dioxide from the flow of blood to the flow of gas through the hollow fibers.

19. The method of claim 18, wherein the plurality of hollow fibers are circumferentially arranged and surrounds the blood outlet channel.

20. A method for pumping and oxygenating blood, the method including:

receiving a flow of gas including oxygen into a gas inlet manifold via a gas inlet of a housing in which the gas inlet manifold is disposed;

passing the flow of gas from the gas inlet manifold to a gas outlet manifold disposed within the housing through an oxygenator assembly having an exterior surface and an interior surface forming an exterior surface of a blood outlet channel, the oxygenator assembly including a plurality of hollow fibers through which the gas outlet manifold is in fluid communication with the gas inlet manifold, the plurality of hollow fibers being arranged circumferentially around the blood outlet channel;

outputting the flow of gas from the gas outlet manifold via a gas outlet of the housing;

rotating an impeller to generate a flow of blood that flows through a blood inlet to a blood inlet channel, through the blood inlet channel to the exterior surface of the oxygenator assembly, from the exterior surface of the oxygenator assembly through the oxygenator assembly and the interior surface of the oxygenator assembly into the blood outlet channel, and through the blood outlet channel to a blood outlet, wherein the blood inlet channel is surrounded by the blood outlet channel;

transferring oxygen from the flow of gas to the flow of blood through the hollow fibers; and

transferring carbon dioxide from the flow of blood to the flow of gas through the hollow fibers.