Apparatus for regulating the temperature of a fluid

• US 6,259,074 B1
• Filed: 10/26/1999
• Issued: 07/10/2001
• Est. Priority Date: 10/26/1999
• Status: Expired due to Term

• Current Assignee: Smiths Medical ASD, Inc. (Smiths Group International Holdings Ltd.)
• Original Assignee: Sims Level 1 Inc. (Smiths Group International Holdings Ltd.)
• Inventors: Kyn, Pavel, Brunner, Charles, Waldron, Vicent, Zarkhin, Eugene B.
• Primary Examiner(s): PASCHALL, MARK H
• Application Number:
  US09/426,717
• Time in Patent Office: 623 Days
• Field of Search: 219/494, 219/496, 219/497, 219/501, 219/505, 219/508, 219/202, 392/441, 392/449, 392/456, 604/113, 604/114
• US Class Current: 219/497
• CPC Class Codes: A61M 2205/14 Detection of the presence or absence of a tube, a connector or a container in an apparatus
• CPC Class Codes: A61M 2205/366 by liquid heat exchangers
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/583 by visual feedback
• CPC Class Codes: A61M 39/10 Tube connectors; Tube couplings A61M39/02 takes precedence; connecting needles to syringes or hubs A61M5/34; connecting catheter tubes to hubs A61M25/0014
• CPC Class Codes: A61M 5/44 having means for cooling or heating the devices or media
• CPC Class Codes: G05D 23/1931 to control the temperature of one space
• CPC Class Codes: G05D 23/24 the sensing element having a resistance varying with temperature, e.g. a thermistor

Abstract

The temperature regulating device of the instant invention accurately regulates the temperature of a fluid to be sent through a conduit for either warming or cooling an infusate that is to be provided to a patient. The heater/cooler that is used for regulating the temperature of the fluid, and the fluid itself, are continuously monitored by a number of sensors, which provide feedback signals to a processor controller, to ensure that the temperature of the fluid is maintained at a desired temperature. The fluid is circulated by a pump which operation is also continuously monitored. A special connector assembly provides the inlet/outlet connection between the device and the fluid conduit. The connector assembly is constructed such that the system would operate only when the connector of the fluid conduit is correctly mated thereto. A calibration device, shaped substantially the same as the connector for the fluid conduit, when mated to the connector assembly, initiates a sequence that include the calibration and testing of various temperature sensitive components in the device.

Claims

1. System for routing a fluid of a given temperature through a heat exchange conduit, comprising:

temperature regulation means for controlling the temperature of said fluid;

connector means demountedly coupling said heat exchange conduit to said system for establishing a closed fluid path between said system and said heat exchange conduit so that said fluid may be circulated between said system and said heat exchange conduit to regulate the temperature of an infusate;

pump means for circulating said fluid between said system and said heat exchange conduit via said connector means;

sensor means for sensing the temperature of said fluid; and

processor means communicatively connected to said temperature regulation means, said pump means and said sensor means, said processor means using the sensed temperature of said fluid by said sensor means as a feedback to control the operation of said temperature regulation means for regulating the temperature of said fluid.

2. System of claim 1, further comprising:

a reservoir for storing said fluid; and

wherein said pump means comprises a reversible action pump adaptable for circulating said fluid between said system and said heat exchange conduit during the operation of said system, said pump further reversing the circulation direction of said fluid so that substantially all of said fluid in said heat exchange conduit is returned to said reservoir before said system ceases operation.

3. System of claim 2, further comprising:

motor sensor means electrically connected to said pump means and said processor means, said motor sensor means sensing the current being utilized by said pump means and reporting said sensed current to said processor means; and

a pump controller electrically connected to said pump means and said processor means;

wherein said processor means utilizes said sensed current reported by said motor sensor means for determining the operational status of said pump, said processor further outputting an instruction to pump controller for changing the direction said pump means circulates said fluid before said system ceases operation.

4. System of claim 1, wherein said connector means comprises bidirectional receptacle ports, further comprising:

a housing whereat said receptacle ports are integrated; and

an other sensor means positioned relative to said receptacle ports for determining whether said heat exchange conduit is correctly mated to said receptacle ports.

5. System of claim 1, further comprising:

a gateway whereat said connector means couples said heat exchange conduit to said system; and

calibration means matable to said gateway for initiating calibration and testing of at least the temperature sensitive components of said system.

6. System of claim 5, wherein said system comprises a housing, said gateway comprises bidirectional receptacle ports at said housing, and said calibration means comprises a body matable to said bidirectional ports, and wherein said sensor means comprises thermistor means and thermostat means, said system further comprising:

an other sensor means located relative to said bidirectional ports for sensing the mating of said calibration body to said bidirectional ports, said sensor means enabling said system to initiate calibration and testing of said thermistor means for maintaining the temperature of said fluid to a desired temperature and said thermostat means for providing a fail-safe shut down of said temperature regulation means.

7. System of claim 1, further comprising:

a display for presenting an interface to a user, said display adaptable for presenting messages to the user in any one of a plurality of languages.

8. System of claim 1, wherein said temperature regulation means comprises a heater, further comprising:

temperature sensor means for detecting the heating temperature of said heater, the heating temperature of said heater being communicatively routed to said processor means, said system shutting down if the heating temperature sensed is above a predetermined threshold.

9. System of claim 1, wherein said sensor means comprises at least two thermistors for sensing the temperature of said fluid, the respective temperatures sensed by said thermistors providing comparative and redundant checks on the regulated temperature of said fluid.

10. System of claim 1, further comprising:

bidirectional ports to which said connector means is coupled;

filter means provided relative to said ports for filtering out microbes and other particulates that might contaminate fluid passages in said system, said fluid and said heat exchange conduit; and

other sensor means positioned relative to said ports for detecting contamination of said filter means.

11. System of claim 1, further comprising:

an ultraviolet light source positioned relative to said reservoir and a tubing in said system through which said fluid flows, said ultraviolet light source directing an ultraviolet light towards said reservoir and/or said tubing for killing any microbes or bacteria that may be present in said fluid.

12. System of claim 1, wherein said connector means comprises bidirectional receptacle ports, further comprising:

a housing whereat said receptacle ports are integrated;

a connector assembly communicatively coupled to said receptacle ports; and

an other sensor means positioned relative to said receptacle ports for continuously monitoring the positioning of said connector assembly relative to said receptacle ports, said other sensor means signaling said processor means to shut down said system if it senses said connector assembly to have been moved relative to said receptacle ports.

13. Apparatus for maintaining the temperature of a fluid to a desired temperature, comprising:

temperature regulating means for controlling the temperature of said fluid;

sensor means for sensing the temperature of said fluid;

pump means for routing said fluid to a heat exchanger to regulate the temperature of an infusate; and

processor means communicatively connected to said temperature sensor means, said sensor means and said pump means, said processor means utilizing the sensed temperature of said fluid from said sensor means as a feedback for controlling the operation of said temperature regulation means to maintain the temperature of said fluid to said desired temperature and the operation of said pump means for routing said fluid to said heat exchanger.

14. Apparatus of claim 13, further comprising:

inlet/outlet port means interposed between said heat exchanger and said pump means;

coupling means fitted to said inlet/outlet port means to enable said heat exchanger to be fluidly connected to said pump means, said pump means operable to circulate said fluid between said heat exchanger and said temperature regulating means so as to maintain the temperature of said fluid substantially at said desired temperature.

15. Apparatus of claim 13, wherein said temperature regulating means comprises a heater;

and

wherein said sensor means comprises at least one temperature sensor for detecting the heating temperature of said heater, the detected heating temperature being communicatively routed to said processor means said system shutting down if the temperature sensed is above a predetermined threshold.

16. Apparatus of claim 14, further comprising:

an electromechanical switch positioned relative to said inlet/outlet port means for determining whether said coupling means is correctly fitted to said inlet/outlet port means.

17. Apparatus of claim 14, further comprising:

calibration means fitted to said inlet/outlet port means for initiating calibration and testing of said sensor means to ensure said temperature regulating means accurately regulates the temperature of said fluid; and

a proximity sensor positioned relative to said inlet/outlet port means, said calibration and testing of said sensor means can begin only when said proximity sensor senses said calibration means being correctly fitted to said inlet/outlet port means.

18. Apparatus of claim 14, further comprising:

a reservoir for storing said fluid; and

wherein said pump means comprises a reversible action pump for circulating said fluid between said temperature regulating means and said heat exchanger, said pump further reversing the circulation direction of said fluid so that substantially all of said fluid in said heat exchanger is returned to said reservoir before said pump ceases operation.

19. Apparatus of claim 14, further comprising:

filter means provided relative to said inlet/outlet port means for substantially filtering out microbes and other particulates that might contaminate said fluid, fluid passages in said system and said heat exchange conduit; and

other sensor means positioned relative to said inlet/outlet port means for detecting any microbial contamination of said filter.

20. Apparatus of claim 13, further comprising:

a reservoir for storing said fluid; and

an ultraviolet light source positioned relative to said reservoir or a tubing that routes said fluid to said heat exchanger, said ultraviolet light source directing an ultraviolet light either to said reservoir and/or said tubing for killing any microbes or bacteria that may be present in said fluid.

21. A device for controlling the temperature of a fluid, comprising:

a reservoir for storing said fluid;

a heater for heating said fluid;

a connector assembly secured to the housing of said device, said assembly adaptable to accept a heat exchange conduit to which said fluid is routed, said heat exchange conduit configured to reflux said fluid to said heater via said connector assembly to thereby establish a closed fluid path between said heater and said heat exchange conduit;

a pump for circulating said fluid between said heat exchange conduit and said heater to regulate the temperature of an infusate in a heat exchange relationship with said heat exchange conduit;

sensor means for sensing the temperature of said fluid; and

processor means communicatively connected to at least said heater, said pump and said sensor, said processor means using the temperature of said fluid sensed by said sensor means as a feedback to control the operation of said heater for regulating the temperature of said fluid.

22. Device of claim 21, wherein said pump is a reversible action pump that circulates said fluid between said heater and said heat exchange conduit in a forward direction during regular operation and circulates said fluid in a reverse direction so as to return substantially all of said fluid in said heat exchange conduit back to said reservoir before said device shuts down.

23. Device of claim 21, further comprising:

switch means positioned relative to said connector assembly for determining whether said heat exchange conduit is correctly mated to said connector assembly.

24. Device of claim 21, further comprising:

temperature checking means fitted to said connector means for enabling calibration and testing of said sensor to ensure the temperature of said fluid is being accurately regulated; and

an other sensor means positioned relative to said connector assembly for sensing whether said temperature checking means is correctly fitted to said connector assembly.

25. Device of claim 21, further comprising:

filter means provided relative to said connector assembly for substantially filtering out microbes or particulates that might contaminate said fluid before said fluid is output via said connector assembly to said heat exchange conduit; and

an other sensor positioned relative to said connector assembly for detecting any microbial contamination at said filter means.

26. Device of claim 21, further comprising:

an ultraviolet light source positioned relative to said reservoir or a tubing that routes said fluid to said heat exchange conduit, said ultraviolet light source directing an ultraviolet light either to said reservoir and/or said tubing for killing any microbes or bacteria that may be present in said fluid.

27. Device of claim 21, wherein said sensor means comprises:

at least one pair of thermistors each for individually sensing the temperatures of said fluid;

wherein said heater is turned off either when the respective temperatures sensed by said thermistors vary by a predetermined amount or when either one of said thermistors senses the temperature of said fluid to be at a given overtemp temperature.

28. Device of claim 21, wherein said sensor means comprises:

a thermostat configured and calibrated to effect an open circuit for shutting down said device when the temperature of said fluid reaches a predetermined overheated temperature.