SYSTEMS AND METHODS FOR Ex vivo LUNG CARE

• US 20090197325A1
• Filed: 04/08/2008
• Published: 08/06/2009
• Est. Priority Date: 01/31/2008
• Status: Active Grant

• Current Assignee: TransMedics, Inc. (TransMedics Group, Inc.)
• Original Assignee: TransMedics, Inc. (TransMedics Group, Inc.)
• Inventors: SULLIVAN, John, FATTAH, Ihab Abdel, BRINGHAM, Richard, BISHOP, Tom, KYI, Stanley, VAN DRIEL, Michael, NEWELL, Scott, ABDELAZIM, Anas, DE REMER, Matthew, HARRIOTT, Doug, MURRAY, Paul, KHAYAL, Tamer, HAVENER, Robert, ANDERSON, Mark, FISHMAN, Robert, TAYLOR, Ron, Hassanein, Waleed
• Granted Patent: US 9,814,230 B2
• Time in Patent Office: Days
• US Class Current: 435/284.1
• CPC Class Codes: A01N 1/02 Preservation of living parts
• CPC Class Codes: A01N 1/021 Preservation or perfusion media, liquids, solids or gases used in the preservation of cells, tissue, organs or bodily fluids
• CPC Class Codes: A01N 1/0247 for perfusion, i.e. for circulating fluid through organs, blood vessels or other living parts

Abstract

Methods and systems of maintaining, evaluating, and providing therapy to a lung ex vivo. The methods and systems involve positioning the lung in an ex vivo perfusion circuit; circulating a perfusion fluid through the lung, the fluid entering the lung through a pulmonary artery interface and leaving the lung through a left atrial interface; and ventilating the lung by flowing a ventilation gas through a tracheal interface. Maintaining the lung for extended periods involves causing the lung to rebreath a captive volume of air, and reaching an equilibrium state between the perfusion fluid and the ventilation gas. Evaluating the gas exchange capability of the lung involves deoxygenating the perfusion fluid and measuring a time taken to reoxygenate the perfusion fluid by ventilating the lung with an oxygenation gas.

Claims

1. A lung care system comprising:

a portable multiple use module including a portable chassis;

a single use disposable module including;

an interface adapted to couple the single use disposable module with the multiple use module for electromechanical interoperation with the multiple use module; and

a lung chamber assembly having a first interface for allowing a flow of a perfusion fluid into the lung, a second interface for allowing ventilation of the lung with a ventilation gas, and a third interface for allowing a flow of the perfusion fluid away from the lung, the lung chamber assembly including a dual drain system for carrying the flow of the perfusion fluid away from the lung, the dual drain system comprising a measurement drain for directing a part of the perfusion fluid flow to a sensor of a perfusion fluid gas content and a main drain for receiving a remaining part of perfusion fluid flow.

2. The system of claim 1, wherein the dual drain further comprises a vessel for collecting the flow of perfusion fluid away from the lung into a pool which feeds into the measurement drain, a drainage capacity of the measurement drain being less than a flow rate of the perfusion fluid away from the lung, wherein excess perfusion fluid overflowing the vessel flows to the main drain.

3. The system of claim 1, wherein the disposable module further comprises a pump adapted to circulate the perfusion fluid through the lung.

4. The system of claim 1 further comprising a ventilation system connected to the second interface for ventilating the lung with a gas having a predetermined composition.

5. The system of claim 4, wherein the predetermined composition includes about 12% oxygen.

6. The system of claim 4, wherein the predetermined composition is about 12% oxygen, about 5.5% carbon dioxide, and about 82.5% nitrogen.

7. The system of claim 1, further including a conduit that provides fluid communication between the main drain and a reservoir for the perfusion fluid.

8. The system of claim 1 wherein the portable multiple use module comprises a lung console for providing at least one of electrical, pneumatic, and mechanical control of the disposable module.

9. The system of claim 8, wherein the lung console includes a ventilation controller for controlling the ventilation of the lung.

10. The system of claim 9, wherein the ventilation controller includes a mechanical actuator for actuating a bellows for causing a flow of ventilation gas into the lung.

11. The system of claim 9, wherein the lung console module includes a pneumatic control system for controlling at least one valve in a ventilation gas circuit connected to the lung in the disposable module.

12. The system of claim 11, wherein the at least one valve is disposed in the ventilation gas circuit between the lung and the bellows, an off position of the valve closing a gas connection between the lung and the bellows.

13. The system of claim 11, wherein the at least one valve includes a relief valve for venting ventilation gas from the lung ventilation circuit.

14. The system of claim 11, wherein the at least one valve includes a trickle valve for introducing a ventilation gas to the ventilation gas circuit.

15. The system of claim 9, wherein the ventilation controller is capable of selecting one of a plurality of gases for ventilating the lung.

16. The system of claim 15, wherein the plurality of gases includes an oxygenation gas, a deoxygenation gas, and a maintenance gas.

17. The system of claim 16, wherein the oxygenation gas is selected from a set consisting of air and a gas containing between 25% and 100% oxygen.

18. The system of claim 16, wherein the deoxygenation gas comprises carbon dioxide and nitrogen.

19. The system of claim 16, wherein the deoxygenation gas is composed of about 6% carbon dioxide and about 94% nitrogen.

20. The system of claim 16, wherein the maintenance gas comprises oxygen, carbon dioxide, and nitrogen.

21. The system of claim 16, wherein the maintenance gas is composed of about 12% oxygen, about 5.5% carbon dioxide, and about 82.5% nitrogen.

22. The system of claim 16, wherein the maintenance gas is supplied from a tank housed within the multiple use module.

23. The system of claim 8, wherein the portable multiple use module comprises a perfusion fluid controller for controlling a perfusion fluid gas component.

24. The system of claim 23, wherein the perfusion fluid controller includes a pneumatic valve controller for controlling a flow of gas to a gas exchanger in the disposable module, wherein the gas exchanger is configured to exchange gases between the flow of gas to the gas exchanger and the perfusion fluid.

25. The system of claim 24, wherein the flow of gas to the gas exchanger comprises a deoxygenation gas for removing oxygen from the perfusion fluid.

26. The system of claim 25, wherein the deoxygenation gas comprises carbon dioxide and nitrogen.

27. The system of claim 25, wherein the deoxygenation gas is composed of about 6% carbon dioxide and about 94% nitrogen.

28. The system of claim 1, wherein the multiple use module includes a monitor for displaying a status of the lung care system and a user interface for controlling an operation of the lung care system.

29. The system of claim 28, wherein the displayed status includes at least one of an oxygen content of the perfusion fluid entering the lung and an oxygen content of the perfusion fluid exiting the lung.

30. The system of claim 28, wherein the monitor displays a real time trace of a ventilation gas pressure where the gas enters the lung, a real time trace of pulmonary arterial pressure of the lung as measured by a pressure sensor located where the perfusion fluid enters the pulmonary artery, and a time-averaged graph of pulmonary arterial pressure.

31. The system of claim 1, wherein the multiple use module includes a monitor for displaying a status of the lung care system during assessment of the lung, and a user interface for controlling an operation of the lung care system, wherein the monitor displays a real time trace of an oxygen content of the perfusion fluid entering the lung and a real time trace of an oxygen content of the perfusion fluid leaving the lung.

32. A lung care system comprising:

a portable multiple use module including a portable chassis and a lung console;

a single use disposable module including;

an interface adapted to couple the single use disposable module with the multiple use module for electromechanical interoperation with the multiple use module; and

a lung chamber assembly having a first interface for allowing a flow of a perfusion fluid into the lung, a second interface for allowing ventilation of the lung with a ventilation gas, and a third interface for allowing a flow of the perfusion fluid away from the lung, wherein

the lung console provides at least one of electrical, pneumatic, and mechanical control of the perfusion fluid and the ventilation gas in the disposable module.

33. The system of claim 32, wherein the lung chamber assembly includes a dual drain system for carrying the flow of the perfusion fluid away from the lung, the dual drain system comprising a measurement drain for directing a part of the perfusion fluid flow to a sensor of a perfusion fluid gas content and a main drain for receiving a remaining part of perfusion fluid flow.

34. The system of claim 33, wherein the dual drain further comprises a vessel for collecting the flow of perfusion fluid away from the lung into a pool which feeds the measurement drain, a drainage capacity of the measurement drain being less than a flow rate of the perfusion fluid away from the lung, wherein excess perfusion fluid overflowing the vessel flows to the main drain.

35. The system of claim 32, wherein the disposable module further comprises a pump adapted to circulate the perfusion fluid through the lung.

36. The system of claim 32, wherein the disposable module further comprises a ventilation system connected to the second interface for ventilating the lung with a gas having a predetermined composition.

37. The system of claim 36, wherein the predetermined composition includes about 12% oxygen.

38. The system of claim 36, wherein the predetermined composition is about 12% oxygen, about 5.5% carbon dioxide, and about 82.5% nitrogen.

39. The system of claim 33, wherein the main drain directs the remaining part of the perfusion fluid to a reservoir.

40. The system of claim 32, wherein the lung console includes a ventilation controller for controlling the ventilation of the lung.

41. The system of claim 40, wherein the ventilation controller includes a mechanical actuator for actuating a bellows for causing a flow of ventilation gas into the lung.

42. The system of claim 40, wherein the lung console module includes a pneumatic control system for controlling at least one valve in a ventilation gas circuit connected to the lung in the disposable module.

43. The system of claim 42, wherein the at least one valve is disposed in the ventilation gas circuit between the lung and the bellows, an off position of the valve closing a fluid connection between the lung and the bellows.

44. The system of claim 42, wherein the at least one valve includes a relief valve for venting ventilation gas from the lung ventilation circuit.

45. The system of claim 42, wherein the at least one valve includes a trickle valve for delivering a ventilation gas to the ventilation gas circuit.

46. The system of claim 40, wherein the ventilation controller is configured to select one of a plurality of gases for ventilating the lung.

47. The system of claim 46, wherein the plurality of gases includes an oxygenation gas, a deoxygenation gas, and a maintenance gas.

48. The system of claim 47, wherein the oxygenation gas is selected from a set consisting of air and a gas containing between 25% and 100% oxygen.

49. The system of claim 47, wherein the deoxygenation gas comprises carbon dioxide and nitrogen.

50. The system of claim 47, wherein the deoxygenation gas is composed of about 6% carbon dioxide and about 94% nitrogen.

51. The system of claim 47, wherein the maintenance gas comprises oxygen, carbon dioxide, and nitrogen.

52. The system of claim 47, wherein the maintenance gas is composed of about 12% oxygen, about 5.5% carbon dioxide, and about 82.5% nitrogen.

53. The system of claim 47, wherein the maintenance gas is supplied from a tank housed within the multiple use module.

54. The system of claim 32, wherein the lung console includes a perfasion fluid controller for controlling a perfusion fluid gas component.

55. The system of claim 54, wherein the perfusion fluid controller includes a pneumatic valve controller for controlling a flow of gas to a gas exchanger in the disposable module, wherein the gas exchanger is configured to exchange gases between the flow of gas to the gas exchanger and the perfusion fluid.

56. The system of claim 55, wherein the flow of gas to the gas exchanger comprises a deoxygenation gas for removing oxygen from the perfusion fluid.

57. The system of claim 56, wherein the deoxygenation gas comprises carbon dioxide and nitrogen.

58. The system of claim 56, wherein the deoxygenation gas is composed of about 6% carbon dioxide and about 94% nitrogen.

59. The system of claim 32, wherein the multiple use module includes a monitor for displaying a status of the lung care system and a user interface for controlling an operation of the lung care system.

60. The system of claim 59, wherein the displayed status includes at least one of an oxygen content of the perfusion fluid entering the lung and an oxygen content of the perfusion fluid exiting the lung.

61. The system of claim 59, wherein the monitor displays a real time trace of a ventilation gas pressure where the gas enters the lung, a real time trace of pulmonary arterial pressure of the lung as measured by a pressure sensor located where the perfusion fluid enters the pulmonary artery, and a time-averaged graph of pulmonary arterial pressure.

62. The system of claim 32, wherein the multiple use module includes a monitor for displaying a status of the lung care system during assessment of the lung, and a user interface for controlling an operation of the lung care system, wherein the monitor displays a real time trace of an oxygen content of the perfusion fluid entering the lung and a real time trace of an oxygen content of the perfusion fluid leaving the lung.

63. A lung care system comprising:

a multiple use module including a chassis; and

a single use disposable module including;

an interface adapted for attachment to the multiple use module;

a lung chamber assembly having a first interface for allowing a flow of a perfusion fluid into the lung, a second interface for allowing ventilation of the lung with a ventilation gas, and a third interface for allowing a flow of the perfusion fluid away from the lung; and

a drain system for draining the perfusion fluid from the lung chamber assembly, the drain system including a measurement conduit and a main drain conduit, the measurement conduit further directing a flow of perfusion fluid to a sensor that is adapted to measure a perfusion fluid gas content.

64. The system of claim 63, wherein the measurement conduit is adapted to place the perfusion fluid in a condition suitable for gas content measurement by the sensor.

65. The system of claim 63, wherein the perfusion fluid gas content is an oxygen content.

66. The system of claim 63, wherein the sensor is a pulse oxymeter.