DISPOSABLE CASSETTE FOR INTRAVENOUS HEAT EXCHANGE CATHETER

• US 20070293919A1
• Filed: 07/23/2007
• Published: 12/20/2007
• Est. Priority Date: 08/24/1998
• Status: Active Grant

• Current Assignee: Zoll Circulation Incorporated (Asahi Kasei Corporation)
• Original Assignee: Radiant Medical, Inc. (Asahi Kasei Corporation)
• Inventors: Alejandro, Jose, Machold, Timothy, Bloom, Nicole, Roth, Alex, Scott, Dave, Oliver, Edward
• Granted Patent: US 8,177,824 B2
• Time in Patent Office: Days
• US Class Current: 607/104
• CPC Class Codes: A61B 2017/00119 alarm; indicating an abnormal situation
• CPC Class Codes: A61B 2017/00123 and automatic shutdown
• CPC Class Codes: A61B 2017/22051 with an inflatable part, e.g. balloon, for positioning, blocking, or immobilisation A61B2017/22048, A61B2017/3486 take precedence
• CPC Class Codes: A61F 2007/0054 with a closed fluid circuit, e.g. hot water
• CPC Class Codes: A61F 2007/0096 with a thermometer
• CPC Class Codes: A61F 2007/126 for invasive application, e.g. for introducing into blood vessels
• CPC Class Codes: A61F 7/0085 Devices for generating hot or cold treatment fluids
• CPC Class Codes: A61F 7/10 Cooling bags, e.g. ice-bags
• CPC Class Codes: A61F 7/12 Devices for heating or cooling internal body cavities
• CPC Class Codes: A61F 7/123 using a flexible balloon containing the thermal element
• CPC Class Codes: A61M 2025/1072 having balloons with two or more compartments
• CPC Class Codes: A61M 2025/1086 having a special balloon surface topography, e.g. pores, protuberances, spikes or grooves
• CPC Class Codes: A61M 2205/127 with provisions for heating or cooling
• CPC Class Codes: A61M 25/1011 Multiple balloon catheters
• CPC Class Codes: A61M 5/44 having means for cooling or heating the devices or media
• CPC Class Codes: F28D 1/0341 with U-flow or serpentine-flow inside the conduits
• CPC Class Codes: F28D 2021/005 for medical applications
• CPC Class Codes: F28F 3/12 Elements constructed in the shape of a hollow panel, e.g. with channels F28D1/02, F28D1/03 take precedence
• CPC Class Codes: F28F 9/0246 Arrangements for connecting header boxes with flow lines

Abstract

A heat exchange fluid supply system for supplying a heat exchange fluid to an intravascular heat exchange catheter includes a disposable cassette having a bulkhead and an external heat exchanger, and which is configured to operate in combination with a reusable master control unit. The bulkhead includes a reservoir section and a pump section. The reservoir section is provided with a means to monitor the amount of heat exchange fluid that is in the system. The bulkhead provides the mechanism for priming the system with heat exchange fluid from an external source and for circulating fluid to the catheter in a closed circuit. The pump section is configured to allow for pumping of heat exchange fluid at a constant pressure.

Claims

1-36. -36. (canceled)

37. A heat exchange circuit for exchanging heat with tissue of a patient, comprising:

an internal heat exchanger;

an external heat exchanger forming a fluid circuit with the internal heat exchanger;

a pump for moving a heat exchange fluid through the fluid circuit; and

,

a vent in the fluid circuit, the vent being permeable to gas but not to fluid.

38. A circuit as in claim 37, further comprising a master control unit, the master control unit having a pump drive mechanism, the master control unit responsive to an input to activate the pump drive mechanism to pump fluid through the fluid circuit.

39. A circuit as in claim 38, wherein the pump is selected from the group consisting of a vane pump, a diaphragm pump, peristaltic pump, an impeller pump, a screw pump, and a gear pump.

40. A circuit as in claim 37, wherein the vent comprises an aperture covered with a hydrophobic material.

41. A circuit as in claim 37, wherein the internal heat exchanger is a heat exchange catheter.

42. A circuit as in claim 41, wherein the heat exchange catheter is a catheter having a plurality of heat exchange lobes.

43. A circuit as in claim 42, wherein at least one of the plurality of heat exchange lobes is curvilinear.

44. A circuit as in claim 42, wherein the plurality of heat exchange lobes are helically disposed around a central axis.

45. A circuit as in claim 37, wherein the external heat exchanger comprises a cassette configured for mating in heat exchange relationship with a heat generating or removing unit.

46. A circuit as in claim 45, further comprising:

a master control unit, the master control unit responsive to input parameters to activate or deactivate the pump.

47. A circuit as in claim 46, wherein the master control unit is also responsive to the input parameters to control the heat generating or removing unit to control the amount of heat added to or removed from the heat exchange fluid.

48. A circuit as in claim 45, wherein the external heat exchanger further comprises a reservoir and the vent comprises an opening disposed at the top of the reservoir, the opening covered by a hydrophobic material.

49. A circuit as in claim 46, further comprising a sensor in communication with the master control unit for sensing a condition of the fluid in the fluid circuit and for generating a signal associated with the condition of the fluid and wherein the master control unit is responsive to the signal to control the pump to stop pumping heat exchange fluid through the fluid circuit.

50. A circuit as in claim 48, wherein said fluid circuit further comprises a reservoir for holding heat exchange fluid that is pumped through the fluid circuit, and wherein the sensor is a fluid level sensor for detecting the fluid level in the reservoir, and the master control unit is responsive to a selected fluid level in the reservoir to stop pumping the heat exchange fluid through the fluid circuit.

51. A circuit as in claim 48, wherein the sensor is an air detector that senses air in the fluid circuit.

52. A heat exchange circuit for exchanging heat with tissue of a patient, comprising:

an internal heat exchanger;

an external heat exchanger forming a fluid circuit with the internal heat exchanger, the external heat exchanger including a cassette configured to be placed into heat exchange relationship with a heat generating or removing unit, the fluid circuit also including a reservoir disposed within the cassette;

a pump for moving a heat exchange fluid through the fluid circuit;

a channel providing access into the circuit for inputting heat exchange fluid into the fluid circuit;

a fluid level sensor for sensing the level of fluid in the reservoir; and

a master control unit capable of receiving an input to start the pump and also capable of receiving a signal from the fluid level sensor, the signal associated with a sensed fluid level.

53. A circuit as in claim 52, wherein the master control unit is responsive to the signal from the fluid level sensor to stop the pump when the signal represents a selected fluid fill condition of the reservoir.

54. A circuit as in claim 53, wherein the fluid fill condition of the reservoir is a full condition representing completion of priming of the fluid circuit.

55. A circuit as in claim 53, wherein the selected fill condition of the reservoir is a low condition.

56. A method for priming a heat exchange circuit for exchanging heat with tissue of a patient, comprising:

providing a fluid circuit including an internal heat exchanger, an external heat exchanger, an input channel for introducing heat exchange fluid into the circuit, a pump for pumping the heat exchange fluid through the heat exchange fluid;

adding heat exchange fluid to the fluid circuit through the input channel;

pumping the heat exchange fluid through the fluid circuit; and

removing gas from the fluid circuit.

57. The method of claim 56, wherein removing gas from the fluid circuit includes displacing the gas from the fluid circuit by pumping the heat exchange fluid through the fluid circuit and separating the gas from the fluid circuit while maintaining the heat exchange fluid in the fluid circuit.

58. The method of claim 57, wherein separating the gas from the fluid circuit includes venting the gas through a vent.

59. The method of claim 58, wherein separating the gas from the fluid circuit includes venting the gas through a hydrophobic vent.

60. The method of claim 57, wherein separating the gas from the fluid circuit includes communicating the gas to a reservoir external to the fluid circuit.

61. The method of claim 56, further comprising:

stopping pumping of heat exchange fluid through the fluid circuit when substantially all of the gas has been removed from the fluid circuit and the fluid circuit is substantially full of heat exchange fluid.

62. A method of automatically priming a heat exchange circuit for exchanging heat with tissue of a patient, the heat exchange circuit including an internal heat exchanger, an external heat exchanger, an input channel for adding heat exchange fluid into the fluid circuit and a pump, at least a portion of the heat exchange circuit configured for mounting on a master control unit, comprising:

sensing when the at least a portion of the heat exchange circuit is mounted on the master control unit and providing a signal to a processor of the master control unit;

supplying heat exchange fluid to the fluid circuit through the input channel;

pumping heat exchange fluid through the fluid circuit in response to the signal provided to the master control unit;

removing air from the fluid circuit;

sensing when substantially all of the air has been removed from the circuit and the fluid circuit is substantially full of heat exchange fluid; and

providing a signal indicating that priming the fluid circuit is complete.

63. The method of claim 62, further comprising:

stopping the pump in response to the signal indicating that priming the fluid circuit is complete.

64. The method of claim 62, further comprising:

notifying a user that priming is complete in response to the signal indicating that priming the fluid circuit is complete.