Method and apparatus to sense temperature in an implantable pump

• US 20020042596A1
• Filed: 09/10/2001
• Published: 04/11/2002
• Est. Priority Date: 04/30/1999
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Olsen, James M., Hartlaub, Jerome T.
• Granted Patent: US 7,658,737 B2
• Time in Patent Office: Days
• US Class Current: 604/288.01
• CPC Class Codes: A61M 2005/14264 with means for compensating influence from the environment
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2205/3372 Temperature compensation
• CPC Class Codes: A61M 2205/52 with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: A61M 2230/50 Temperature
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: F04B 13/00 Pumps specially modified to deliver fixed or variable measured quantities
• CPC Class Codes: F04B 2201/0403 Carter housing temperature

Abstract

An implantable drug infusion pump for delivering drug therapy is made more reliable and its performance improved by monitoring drug pump temperature. Monitoring pump temperature can also provide for temperature-related drug therapy modification.

A pump temperature sensor is read by the infusion pump'"'"'s microprocessor. Pump temperature data is stored in pump memory for later access by a remote controller. A simple thermistor or semiconductor temperature sensor can provide fast and reliable temperature monitoring of the pump and/or of a patient by reading the temperature sensor'"'"'s value and calculating a temperature therefrom.

Claims

1. An automatic drug therapy delivery system, capable of detecting the possibility of damage to the pump prior to implant, the system comprising:

a) an implantable pump;

b) a temperature sensor producing electrically measurable signals that are indicative of temperature of the implantable pump over time; and

c) a controller having at least one input for receiving the signals from the temperature sensor, the controller configured to monitor the signals from the temperature sensor, the controller generating a temperature profile from the signals, the temperature profile being retrievable to detect a possible pump damaging temperature extreme.

2. The apparatus of claim 1, wherein the temperature profile comprises a histogram.

3. The apparatus of claim 2, wherein the histogram comprises ranges of high temperature, normal temperature, and low temperature.

4. The apparatus of claim 1, further comprising a data link coupled to the controller for the retrieval of the temperature profiles.

5. The apparatus of claim 1, wherein the controller comprises a microprocessor.

6. The apparatus of claim 1, further comprising a clock, operatively coupled to the controller, the clock generating an output signal representative of time and date.

7. The apparatus of claim 1, further comprising at least one storage device for storing the temperature profile.

8. The apparatus of claim 1, further comprising a plurality of memory storage locations wherein the temperature profile of the implantable pump is stored.

9. A method of detecting the possibility of pump damage prior to the implantation of an automatic drug delivery system, the method comprising the steps of:

a) sensing a temperature of an implantable pump and generating an electrically measurable signal indicative of the temperature of the implantable pump;

b) storing the signal in a memory; and

c) generating a historical representation of the signal from the memory to detect a damaging temperature extreme of the implantable pump.

10. The method of claim 9, wherein the historical representation comprises a histogram.

11. The method of claim 10, wherein the histogram comprises ranges of high temperature, normal temperature, and low temperature.

13. The apparatus of claim 12, wherein the predetermined relationship comprises a proportional relationship between body temperature and pump flow rate.

14. The apparatus of claim 12, wherein the predetermined relationship comprises a proportional relationship between body temperature and pump cycles.

15. The apparatus of claim 12, further comprising a data link coupled to the controller for the retrieval of the temperature signal.

16. The apparatus of claim 12, wherein the controller comprises a microprocessor.

17. The apparatus of claim 12, further comprising a clock operatively coupled to the controller for generating an output signal representative of time and date.

18. The apparatus of claim 12, further comprising at least one storage device for storing the temperature signal.

19. The apparatus of claim 12, further comprising a plurality of memory storage locations wherein data values representing historical temperatures of the implantable pump are stored.

12. An implantable drug therapy delivery system, capable of being implanted into a patient to adaptively administer a drug therapy regimen based on patient temperature comprising:

a) a pump;

b) a temperature sensor for sensing a patient'"'"'s body temperature, the temperature sensor generating a signal related to the body temperature of the patient; and

c) a controller having at least one input for receiving and monitoring the signal from the temperature sensor and responsively regulating the drug therapy to the patient based upon a predetermined relationship to maximize therapeutic effect.

20. A method of delivering a drug therapy to a patient comprising the steps of:

a) delivering the drug therapy to the patient;

b) sensing a body temperature of the patient and generating an electrically measurable signal indicative of the body temperature of the patient;

c) monitoring the electrically measurable signal to detect a high body temperature of the patient;

d) determining whether the drug therapy needs to be adjusted based on a predetermined relationship to maximize the therapeutic effect of the drug therapy; and

e) adjusting, if necessary, delivery of the drug therapy to the patient in response to the electrically measurable signal.

21. A controller for use with an implantable device comprising:

a) an input for receiving temperature signals relating to temperature of the implantable device; and

b) computer-executable instructions for determining a possible malfunction of the implantable device resulting from an extreme temperature of the implantable device.

22. A controller for use with an implantable device comprising:

a) at least one input for receiving a signal indicative of a device temperature; and

b) computer-executable instructions for monitoring the signal and generating a temperature profile to provide a historical representation in a plurality of predetermined categories in relative amounts of time that the implantable device experienced in each of the categories of temperature to detect a possible pump damaging temperature extreme.

24. The controller of claim 23, wherein the predetermined relationship comprises a relationship between body temperature and pump flow rate.

25. The controller of claim 23, wherein the predetermined relationship comprises a relationship between body temperature and pump cycles.

27. The apparatus of claim 26, wherein the program instructions comprise a predetermined relationship between temperature and pump cycles.

28. The apparatus of claim 26, wherein the controller comprises a microprocessor.

29. The apparatus of claim 26, wherein the pump comprises a propellant pump.

30. The apparatus of claim 29, wherein the uncompensated flow comprises a propellant for the propellant pump.

23. A controller for use with an implantable device to adaptively administer a drug therapy regimen based on a patient'"'"'s body temperature comprising:

a) at least one input for receiving a signal indicative of the patient'"'"'s body temperature; and

b) computer-executable instructions for monitoring the signal and responsively regulating the drug therapy regimen to the patient based upon a predetermined relationship to maximize therapeutic effect.

26. An implantable drug therapy delivery system, capable of being implanted into a patient to adaptively administer a drug therapy regimen comprised of:

a) a pump delivering an uncompensated flow of drug therapy;

b) a temperature sensor for producing an electrically measurable signal that is indicative of the temperature of the uncompensated flow; and

c) a controller having at least one input for receiving the signal from the temperature sensor, the controller configured to monitor the signal from the temperature sensor, the controller responsively executing program instructions so as to administer a compensated flow of drug therapy regimen to the patient from the pump based upon the signal.

31. A controller for use with an implantable device comprising:

a) at least one input for receiving a signal indicative of a device temperature;

b) computer-executable instructions for monitoring the signal and generating a temperature profile to provide a historical representation in a plurality of predetermined categories in relative amounts of time that the implantable device experienced in each of the categories of temperature to detect a possible pump damaging temperature extreme; and

c) further computer-executable instruction for determining whether the device is suitable for implant in a patient.

32. The controller of claim 31, wherein the device is an implantable pump.