IV fluid warming system with detection of presence and alignment of cassette

• US 20010009610A1
• Filed: 02/14/2001
• Published: 07/26/2001
• Est. Priority Date: 03/09/1999
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: Arizant Healthcare Inc. (3M Company)
• Inventors: Maharaji, Gary Rabindranath, Augustine, Scott Douglas, Ziaimehr, Allen Hamid, Entenman, Scott Allen
• Granted Patent: US 6,535,689 B2
• Time in Patent Office: Days
• US Class Current: 392/470
• CPC Class Codes: A61M 2205/60 with identification means
• CPC Class Codes: A61M 5/44 having means for cooling or heating the devices or media

Abstract

An intravenous (IV) fluid warming system with a removable heat exchanger includes a presence detector. The system is for warming an IV fluid before infusion into a body. The system includes a warming unit for warming the IV fluid and an inlet slot for receiving a heat exchanger, preferably embodied as a cassette . The heat exchanger is sized to fit into the inlet slot of the warming unit. The heat exchanger has a heat exchanger membrane with an internal fluid pathway that is in fluid communication with a fluid inlet port and a fluid outlet port. While the heat exchanger is in the warming unit, the IV fluid flows through the internal fluid pathway of the heat exchanger, warming the fluid. A heat exchanger presence detector is part of the warming system. The presence detector detects the presence of the heat exchanger when it is received in the warming unit. The presence detector enables the heating operation of the warming unit when the presence of the heat exchanger is sensed.

Claims

1. An intravenous (IV) fluid warming system comprising:

a warming unit with an inlet slot;

a heat exchanger receivable in the warming unit inlet slot, the heat exchanger having a fluid inlet port and a fluid outlet port in fluid communication with an internal fluid pathway in the heat exchanger; and

a presence detector acting between the warming unit and the heat exchanger to sense the presence of the heat exchanger in the warming unit.

2. The system of

claim 1

, wherein the presence detector comprises:

a first circuit element in the warming unit;

a second circuit element on the heat exchanger, the second element cooperating with the first circuit element to enable a signal representing a condition between the heat exchanger and the warming unit.

3. The system of

claim 2

further including;

an indicator connected to the first circuit element for giving an indication of the condition.

4. The system of

claim 3

, wherein the indication is of receipt of the heat exchanger in the warming unit.

5. The system of

claim 1

, wherein the presence detector includes a magnetic switch comprising:

a sensor and a magnet in the warming unit with a gap between them; and

a presence indicator on the heat exchanger sized to fit within the gap between the magnet and sensor.

6. The system of

claim 1

, wherein the presence detector includes a mechanical switch located on the warming unit to be engaged by the heat exchanger when the heat exchanger is in the warming unit.

7. The system of

claim 1

, wherein the presence detector includes an electronic switch having a sensor located in the warming unit to sense the heat exchanger when the heat exchanger is in the warming unit.

8. The system of

claim 1

, wherein the presence detector includes a radio frequency transceiver in the warming unit and a passive transmitter in the to sense the heat exchanger when the heat exchanger is in the warming unit.

9. The system of

claim 1

, wherein heat exchanger comprises;

a frame; and

a heat exchanger membrane attached to the frame;

a first layer of heat exchanger membrane; and

a second layer of the heat exchanger membrane joined to the first layer by a substantially continuous seam around the peripheries of the layers.

10. The system of

claim 9

, wherein the first layer and second layer are made of a thermoplastic material and are joined by a thermal bond.

11. The system of

claim 9

further comprising:

the first layer also being joined to the second layer at a plurality of locations within the substantially continuous seam, forming an internal fluid pathway with a plurality of connected channels.

12. The system of

claim 11

, wherein the internal fluid pathway is serpentine in shape.

13. The system of

claim 9

further comprising:

a fluid inlet port in fluid communication with a first end of the internal fluid pathway;

a fluid inlet line having a first end in fluid communication with the fluid inlet port and a second end connectable to an IV fluid container;

a fluid exit port in fluid communication with a second end of the internal fluid pathway; and

a fluid outlet line having a first end in fluid communication with the fluid outlet port and a second end connectable with a patient infusion system.

14. The system of

claim 9

, the frame including a handle.

15. The system of

claim 1

further comprising:

an attachment means for attaching the warming unit to an IV pole.

16. The system of

claim 15

, wherein the attachment means is a clamp.

17. The system of

claim 1

, wherein the warming unit comprises:

a first heater plate positioned on one side of the inlet slot; and

a second heater plate positioned on an opposite side of the inlet slot.

18. The system of

claim 1

, wherein the heat exchanger is a disposable cassette

19. The system of

claim 1

further comprising:

a warming unit controller, and

a controller display window connected to the warming unit controller.

20. The system of

claim 19

further comprising:

a thermocouple positioned in the warming unit

21. The system of

claim 20

wherein the thermocouple is in communication with the warming unit controller.

22. An intravenous (IV) fluid warming system comprising:

a warming unit with;

an enclosure having an inlet slot;

at least one heating element positioned in the enclosure;

a heat exchanger comprising;

a frame receivable to be received in the inlet slot,

a heat exchanger membrane attached to the frame, the heat exchanger membrane having an internal fluid pathway;

a fluid inlet port near a first end of the internal fluid path;

a fluid outlet port near a second end of the internal fluid path; and

a presence detector acting between the heat exchanger and the warming unit.

23. The system of

claim 22

, wherein the enclosure comprises a first enclosure portion with a handle and a second enclosure portion.

24. The system of

claim 22

, wherein the presence detector comprises:

a first circuit element in the warming unit;

a second circuit element positioned on the heat exchanger, the second element cooperative with the first circuit element to enable a signal representing a condition between the heat exchanger and the warming unit.

25. The system of

claim 24

further including;

an indicator connected to the first circuit element for giving an indication of the condition.

26. The system of

claim 25

, wherein the indication is of receipt of the heat exchanger in the warming unit.

27. The system of

claim 24

, wherein the first element includes a sensor.

28. The system of

claim 27

, wherein the first element further includes a mechanical switch connected to the sensor and the second circuit element includes a switch contactor.

29. The system of

claim 22

, wherein the presence detector is a magnetic switch having a magnet near one side of the inlet slot, a sensor near another side of the inlet slot and a controller connected to the sensor.

30. The system of

claim 22

further comprising:

a warming unit controller; and

a controller display window connected to the warming unit controller.

31. The system of

claim 30

further comprising:

a thermocouple positioned in the warming unit

32. The system of

claim 22

wherein the thermocouple is in communication with the warming unit controller.

33. A method of using an intravenous (IV) fluid warming system that includes a warming unit and a heat exchanger, the method comprising the steps of:

inserting the heat exchanger into the inlet; and

providing an indication that the heat exchanger is received in the inlet.

34. The method as defined in

claim 33

, further including enabling operation of the warming unit in response to the indication.

35. The method as defined in

claim 34

, further including removing the indication when the heat exchanger is removed from the inlet.

36. The method defined in

claim 35

, further including disabling operation of the warming unit in response to removing the indication.

37. A heat exchanger for being received in a warming unit for being warmed therein, comprising:

an IV fluid cassette with an internal fluid pathway; and

a presence indicator on the cassette.

38. The heat exchanger of

claim 37

, wherein the presence indicator comprises a magnetic material.

39. The heat exchanger of

claim 37

, wherein the presence indicator comprises a void in the cassette.

40. A warming unit with an opening for receiving an IV fluid heat exchanger to be warmed by the warming unit, comprising:

an enclosure;

a heat exchanger warming assembly in the enclosure; and

a heat exchanger presence detector circuit in the enclosure connected to the warming assembly.