HEAT EXCHANGE SYSTEMS, DEVICES AND METHODS

• US 20110218600A1
• Filed: 01/31/2011
• Published: 09/08/2011
• Est. Priority Date: 04/14/2006
• Status: Active Grant

• Current Assignee: Deka Products Limited Partnership
• Original Assignee: Deka Products Limited Partnership
• Inventors: Owens, Kingston, Perry, N. Christopher, van der Merwe, Dirk A., Tracey, Brian, Kamen, Dean, Demers, Jason A., Gray, Larry B., Dale, James D., Altobelli, David E.
• Granted Patent: US 8,968,232 B2
• Time in Patent Office: Days
• US Class Current: 607/104
• CPC Class Codes: A61F 2007/126 for invasive application, e.g. for introducing into blood vessels
• CPC Class Codes: A61M 1/16 with membranes
• CPC Class Codes: A61M 1/1605 Physical characteristics of the dialysate fluid
• CPC Class Codes: A61M 1/1656 Apparatus for preparing dialysates
• CPC Class Codes: A61M 1/287 Dialysates therefor
• CPC Class Codes: A61M 1/362227 the interface providing means for actuating on functional elements of the cassette, e.g. plungers
• CPC Class Codes: A61M 1/36225 with blood pumping means or components thereof
• CPC Class Codes: A61M 1/362263 Details of incorporated filters
• CPC Class Codes: A61M 1/362265 Details of valves
• CPC Class Codes: A61M 1/3626 Gas bubble detectors
• CPC Class Codes: A61M 1/369 Temperature treatment
• CPC Class Codes: A61M 2205/12 with interchangeable cassettes forming partially or totally the fluid circuit
• CPC Class Codes: A61M 2205/127 with provisions for heating or cooling
• CPC Class Codes: A61M 2205/128 with incorporated valves
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 2205/3324 PH measuring means
• CPC Class Codes: A61M 2205/3334 Measuring or controlling the flow rate
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2205/3606 cooled
• CPC Class Codes: A61M 2205/3653 by Joule effect, i.e. electric resistance
• CPC Class Codes: A61M 2205/502 : User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 60/113 : in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/36 : for specific blood treatment; for specific therapy
• CPC Class Codes: A61M 60/43 : using vacuum at the blood pump, e.g. to accelerate filling
• CPC Class Codes: A61M 60/554 : of blood pressure
• CPC Class Codes: A61M 60/837 : Aspects of flexible displacement members, e.g. shapes or materials
• CPC Class Codes: A61M 60/847 : arranged in a cassette
• CPC Class Codes: A61M 60/849 : Disposable parts
• CPC Class Codes: A61M 60/851 : Valves
• CPC Class Codes: A61M 60/892 : Active valves, i.e. actuated by an external force
• CPC Class Codes: A61M 60/894 : Passive valves, i.e. valves actuated by the blood
• CPC Class Codes: F04B 23/06 : the pumps being all of reciprocating positive-displacement type
• CPC Class Codes: F04B 39/12 : Casings; Cylinders; Cylinder heads; Fluid connections
• CPC Class Codes: F04B 39/123 : Fluid connections
• CPC Class Codes: F04B 39/14 : Provisions for readily assembling or disassembling
• CPC Class Codes: F04B 43/0081 : systems, control, safety measures
• CPC Class Codes: F04B 43/073 : the actuating fluid being controlled by at least one valve
• CPC Class Codes: F04B 43/0736 : with two or more pumping chambers in parallel
• CPC Class Codes: F04B 53/16 : Casings; Cylinders; Cylinder liners or heads; Fluid connections
• CPC Class Codes: F04B 53/22 : Arrangements for enabling ready assembly or disassembly
• CPC Class Codes: F04B 7/02 : the valving being fluid-actuated
• CPC Class Codes: G01K 1/08 : Protective devices, e.g. casings
• CPC Class Codes: G01K 1/16 : Special arrangements for conducting heat from the object to the sensitive element
• CPC Class Codes: G01M 3/188 : for radiators
• CPC Class Codes: G05D 7/0682 : using a plurality of flow sources
• CPC Class Codes: Y02A 90/10 : Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

Abstract

Embodiments of the present invention relate generally to heat-exchanger systems that can be used to heat or cool a fluid such as blood. Pod pumps that provide low shear and low turbulence may be used in such systems, particularly for systems that pump blood. A certain heat-exchanger system used to heat blood or other fluids may be used to provide whole-body hyperthermic treatments or regional hyperthermic chemotherapy treatments. A disposable unit may be used to separate the fluid path from the fluid control systems. The disposable unit typically includes a heat-exchanger component that is received by a corresponding heat exchanger in a base unit. Fluid pumped through the heat-exchanger component is heated by the heat exchanger.

Claims

1. A method for heating or cooling a liquid using a controller to control a fluidly actuated pumping cassette, the method comprising:

opening an inlet valve on the cassette to fluidly connect a source of the liquid with at least one reciprocating positive-displacement pump on the cassette, each pump comprising;

a curved rigid chamber wall;

a flexible membrane attached to the rigid chamber wall, the flexible membrane and rigid chamber wall defining a pumping chamber;

a rigid limit structure for limiting movement of the membrane and limiting the maximum volume of the pumping chamber, the flexible membrane and the rigid limit structure defining an actuation chamber connected via a fluidic control port in the rigid limit structure to a fluid source under positive or negative pressure; and

a pressure transducer configured to measure a pressure in the pumping chamber or the actuation chamber to provide pressure information to the controller;

introducing a quantity of the liquid into the pumping chamber through the inlet valve;

closing the inlet valve and fluidly isolating the pumping chamber;

applying a known pressure to the actuation chamber;

measuring a rate of pressure change in the pumping chamber or the actuation chamber;

comparing the measured rate of pressure change with the controller to a pre-determined range of values; and

opening an outlet valve fluidly connected to an outlet of the pumping chamber and pumping the liquid from the outlet to a heat exchanger only if the measured rate of pressure change is within a pre-determined range of values.

2. A method according to claim 1, wherein the rigid chamber wall is hemispheroid.

3. A method according to claim 2, wherein the rigid limit structure is hemispheroid, such that the pumping chamber is spheroid when the membrane is urged against the rigid limit structure and the actuation chamber is spheroid when the membrane is urged against the rigid chamber wall.

4. A method according to claim 1, wherein the at least one reciprocating positive-displacement pump comprises a pair of reciprocating positive-displacement pumps.

6. A method according to claim 1, wherein the at least one pump is fluidly connected to a disposable conduit having an inlet and an outlet, and wherein the method further comprises:

placing the disposable conduit in proximity with the heat exchanger; and

pumping the liquid through the disposable conduit so as to heat or cool the liquid.

7. A method according to claim 6, wherein the disposable conduit includes at least one of a heat-exchanger bag, a length of tubing, and a radiator.

8. A method according to claim 1, wherein the source is a patient and the liquid is a bodily fluid.

9. A method according to claim 8, further comprising:

monitoring the patient'"'"'s temperature; and

controlling the operation of at least one of (a) the at least one pump and (b) the heat exchanger in order to maintain the temperature of the liquid within a predetermined range.

10. A method according to claim 1, wherein the actuation chamber is fluidly connected to a pneumatic actuation system for providing either a positive or a negative pressure to the actuation chamber of each pump.

11. A method according to claim 10, wherein the pneumatic actuation system includes:

a gas reservoir containing a gas at either a positive or a negative pressure, and

a valving mechanism for controlling the flow of gas between the gas reservoir and the actuation chamber of each pump.

12. A method according to claim 11, wherein the controller receives pressure information from at least one actuation-chamber pressure transducer and controls the valving mechanism.

13. A method according to claim 12, wherein the pneumatic actuation system further comprises a reservoir pressure transducer for measuring the pressure of the gas in the reservoir, and wherein the controller receives pressure information from the reservoir pressure transducer.

14. A method according to claim 13, wherein the controller compares pressure information from the actuation-chamber pressure transducer with pressure information from the reservoir pressure transducer to determine whether at least one pressure transducer is malfunctioning.

15. A method according to claim 1, wherein a pneumatic actuation system provides positive pressure alternating with negative pressure to the actuation chamber of each pump.

16. A method according to claim 15, wherein the pneumatic actuation system comprises:

a positive-pressure gas reservoir;

a negative-pressure gas reservoir; and

a valving mechanism for controlling the flow of gas between the gas reservoirs and the actuation chamber of each pump.

17. A method according to claim 16, wherein the pneumatic actuation system further comprises:

at least one actuation-chamber pressure transducer for measuring the pressure of the actuation chamber of each pump, and wherein

the controller receives pressure information from the at least one actuation-chamber pressure transducer and controls the valving mechanism.

18. A method according to claim 17, wherein the controller controls the valving mechanism to cause the flexible membrane of each pump to move toward the rigid chamber wall in a pump stroke beginning or move toward the rigid limit structure in a pump stroke end, and

wherein the controller determines the amount of fluid flow through each pump based on a number of pump strokes.

19. A method according to claim 18, wherein the controller integrates pressure information received from an actuation-chamber pressure transducer during a pump stroke to detect an aberrant flow condition.

20. A method according to claim 1, wherein the inlet valve prevents flow out of the pumping chamber through an inlet of each pump and the outlet valve prevents flow into the pumping chamber through the outlet.

21. A method according to claim 20, wherein the controller controls the inlet valve and the outlet valve.

31. A method according to claim 1, wherein the inlet valve and the outlet valve each comprises a flexible valve membrane capable of occluding liquid flow in the valve, and an actuation housing with actuation port to transmit fluid under positive or negative pressure to the flexible valve membrane.

33. A method according to claim 1, wherein the fluid source is a pneumatic source.

35. A method according to claim 1, wherein the predetermined range of values comprises a predetermined rate of change in measured pressure in response to the application of the known pressure to the actuation chamber.

37. A method according to claim 1, wherein the pressure transducer is in fluid communication with the actuation chamber.

5. A method according to claim 5, wherein the pair of pumps are operated out of phase so as to produce a substantially continuous liquid flow.

22. A fluidly activated liquid pumping system comprising:

a controller; and

a disposable cassette comprising;

(a) at least one reciprocating positive-displacement pump, each pump comprising;

(i) a curved rigid chamber wall;

(ii) a flexible membrane attached to the rigid chamber wall, the flexible membrane and rigid chamber wall defining a pumping chamber;

(iii) a rigid limit structure for limiting movement of the membrane and limiting the maximum volume of the pumping chamber, the flexible membrane and the rigid limit structure defining an actuation chamber;

(iv) a port in the rigid limit structure fluidly connecting the actuation chamber to a fluid source supplying fluid at a positive or negative pressure to actuate the flexible membrane; and

(v) a pressure transducer configured to measure a fluid pressure in the pumping chamber or the actuation chamber and to provide pressure information to the controller;

(b) an inlet valve for directing liquid into the pumping chamber through an inlet in the rigid chamber wall; and

(c) an outlet valve for directing liquid out of the pumping chamber through an outlet in the rigid chamber wall;

wherein

pressure readings from the pressure transducer are used by the controller to detect the presence of air in the pumping chamber when a known pressure is applied to the actuation chamber via the port, and the inlet valve and the outlet valve are both closed; and

wherein

the outlet in the rigid chamber wall is connected to a fluid conduit comprising a heat-exchanger bag or a radiator.

23. A fluidly activated liquid pumping system according to claim 22, wherein each rigid chamber wall is hemispheroid.

24. A fluidly activated liquid pumping system according to claim 22, wherein the inlet valve prevents flow out of the pumping chamber through the inlet and the outlet valve prevents flow into the pumping chamber through the outlet.

25. A fluidly activated liquid pumping system according to claim 24, wherein the inlet valve and the outlet valve are controlled by the controller.

26. A fluidly activated liquid pumping system according to claim 22, wherein the fluid conduit includes an inlet in fluid communication with the outlet of the at least one pump for pumping fluid into the fluid conduit for heating or cooling.

27. A fluidly activated liquid pumping system according to claim 22, further comprising:

a filter in fluid communication with an outlet of the fluid conduit for filtering heated or cooled fluid flowing out of the fluid conduit.

28. A fluidly activated liquid pumping system according to claim 22, further comprising:

a manifold including;

at least one inlet port for providing fluidic connection to an inlet of the fluid conduit; and

an outlet port for providing fluidic connection to an outlet of the fluid conduit.

29. A fluidly activated liquid pumping system according to claim 28, wherein the manifold further includes at least one sensor component, each sensor component disposed in a port and capable of transmitting thermal information regarding fluid passing through the port.

30. A fluidly activated liquid pumping system according to claim 29, wherein each sensor component includes a thermal well.

32. A disposable cassette according to claim 22, wherein the inlet valve and the outlet valve each comprises a flexible valve membrane capable of occluding liquid flow in the valve, and an actuation housing with actuation port to transmit fluid under positive or negative to actuate the flexible valve membrane.

34. A fluidly activated liquid pumping system according to claim 22, wherein the fluid source is a pneumatic source.

36. A fluidly activated liquid pumping system according to claim 22, wherein the pressure readings comprise a rate of change of pressure in the actuation chamber or pumping chamber and wherein the controller is configured to compare a measured rate of pressure change to a pre-determined range of values and open the outlet valve to enable pumping the liquid from the outlet to the heat-exchanger bag or radiator only if the measured rate pressure change is within the pre-determined range of values.

38. A method according to claim 22, wherein the pressure transducer is in fluid communication with the actuation chamber.