IMPLANTABLE MEDICAL PUMP DIAGNOSTICS

• US 20120109099A1
• Filed: 11/01/2010
• Published: 05/03/2012
• Est. Priority Date: 11/01/2010
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Rogers, Charles R., Ali, Irfan Z., Mezera, Ronald L., Miesel, Keith A., Sarkinen, Scott A., Whitehead, Nicholas R.
• Granted Patent: US 9,192,719 B2
• Time in Patent Office: Days
• US Class Current: 604/500
• CPC Class Codes: A61M 2005/16863 Occlusion detection
• CPC Class Codes: A61M 2005/16868 Downstream occlusion sensors
• CPC Class Codes: A61M 2005/16872 Upstream occlusion sensors
• CPC Class Codes: A61M 5/14216 Reciprocating piston type
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/16809 by repeated filling and emptying of an intermediate volume pressure infusion using positive displacement pumps A61M5/142

Abstract

A method of detecting a fault condition within an implantable medical pump comprises delivering therapeutic fluid using a medical pump comprising an actuation mechanism configured to be energized to provide a pump stroke, detecting a property associated with energizing the actuation mechanism, and determining whether the property associated with energizing the actuation mechanism indicates that a fault condition exists with the medical pump.

Claims

1. A method of detecting a fault condition within an implantable medical pump, the method comprising:

delivering therapeutic fluid using a medical pump comprising an actuation mechanism configured to be energized to provide a pump stroke;

detecting a property associated with energizing the actuation mechanism; and

determining whether the property associated with energizing the actuation mechanism indicates that a fault condition exists within the medical pump.

2. The method of claim 1, wherein the fault condition comprises one of a plurality of fault condition types, the method further comprising identifying which of the plurality of fault condition types exists.

3. The method of claim 1, wherein the fault condition comprises at least one of:

a full stall of the actuation mechanism, a partial stall of the actuation mechanism, a high energy pump stroke, a low energy pump stroke, gas accumulation within the medical pump, air locking of the medical pump, voltage depletion of a power source, blockage in a flow path of the medical pump, an electrical short in the actuation mechanism, and on open switch between a power source and the actuation mechanism.

4. The method of claim 1, wherein determining whether the property associated with energizing the actuation mechanism indicates that a fault condition exists comprises at least one of:

determining whether the property associated with energizing the actuation mechanism of each of a predetermined number of a set of prior pump strokes indicates that the fault condition exists, or determining whether the property associated with energizing the actuation mechanism of each of a predetermined number of consecutive pump strokes indicates that the fault condition exists.

5. The method of claim 1, further comprising performing a recovery action to attempt to remedy the fault condition if it is determined that the property associated with energizing the actuation mechanism indicates the fault condition exists.

6. The method of claim 5, wherein performing the recovery action comprises initiating a recovery sequence.

7. The method of claim 5, wherein the recovery action comprises at least one of:

delivering a bolus of fluid through the medical pump;

increasing a drive voltage of the actuation mechanism;

increasing or decreasing a charge time of a capacitor that drives actuation mechanism, increasing a rate of pump strokes delivered by the medical pump, initiating a pump reset, reinitializing the medical pump, and placing the medical pump into a reduced delivery mode.

8. The method of claim 5, further comprising determining whether the recovery action resolved the fault condition after performing the recovery action.

9. The method of claim 1, wherein the property associated with energizing the actuation mechanism comprises at least one of:

a shape of at least a portion of an electrical current waveform through the actuation mechanism when the actuation mechanism is energized to provide a pump stroke;

a total energy supplied to the actuation mechanism in order to produce a pump stroke;

a voltage change across the actuation mechanism during a pump stroke; and

an outlet fluid pressure of the medical pump.

10. The method of claim 1, wherein the property associated with energizing the actuation mechanism comprises a shape of at least a portion of an electrical current waveform through the actuation mechanism when the actuation mechanism is energized to provide a pump stroke, wherein the shape of the current waveform is defined by at least one of:

a time from a start of the current waveform to an initial peak current;

a change in time between the initial peak current and a subsequent nadir in the current waveform;

an amplitude value of the initial peak current;

a change in current value between the initial peak current and the subsequent nadir; and

a time from the start of the current waveform to a nadir indicating an end of a pump stroke.

11. The method of claim 1, wherein the property associated with energizing the actuation mechanism comprises a shape of at least a portion of an electrical current waveform through the actuation mechanism when the actuation mechanism is energized to provide a pump stroke, the method further comprising storing a baseline shape that indicates a normal pump stroke in a memory, determining a shape of at least a portion of a current waveform through the actuation mechanism when the actuation mechanism is energized to provide a pump stroke, and comparing the baseline shape to the shape of the portion of the current waveform through the actuation mechanism to provide the pump stroke to determine if the fault condition exists.

12. The method of claim 1, further comprising initiating an alarm if it is determined that the property associated with energizing the actuation mechanism indicates the fault condition exists.

13. The method of claim 1, further comprising logging a time stamp indicating the time at which the fault condition was determined to exist.

14. The method of claim 1, further comprising monitoring the medical pump and determining whether the fault condition has been resolved.

15. The method of claim 14, wherein determining whether the fault condition has been resolved comprises at least one of:

determining that the property associated with energizing the actuation mechanism of each of a predetermined number of a set of prior pump strokes indicates that the fault condition has been resolved, or determining that the property associated with energizing the actuation mechanism of each of a predetermined number of consecutive pump strokes indicates that the fault condition has been resolved.

16. The method of claim 14, if it is determined that the fault condition has been resolved, further comprising logging a time stamp indicating the time at which the fault condition was resolved.

17. The method of claim 14, further comprising initiating an alarm when it is determined that the property associated with energizing the actuation mechanism indicates the fault condition exists and clearing the alarm when it is determined that the fault condition has been resolved.

18. A medical device system comprising:

a medical pump configured to deliver a therapeutic fluid to a patient, the medical pump comprising an actuation mechanism configured to be energized to provide a pump stroke;

a sensor configured to detect a property associated with energizing the actuation mechanism; and

a processor configured to determine whether the property associated with energizing the actuation mechanism indicates that a fault condition exists within the medical pump.

19. The system of claim 18, wherein the actuation mechanism comprises a coil configured to be energized to provide a pump stroke and an actuator that is movable in response to the energization of the coil.

20. The system of claim 18, wherein the fault condition comprises one of a plurality of fault condition types, and wherein the processor is further configured to identify which of the plurality of fault condition types exists.

21. The system of claim 18, wherein the fault condition comprises at least one of:

a full stall of the actuation mechanism, a partial stall of the actuation mechanism, a high energy pump stroke, a low energy pump stroke, gas accumulation within the medical pump, air locking of the medical pump, voltage depletion of a power source, blockage in a flow path of the medical pump, an electrical short in the actuation mechanism, and on open switch between a power source and the actuation mechanism.

22. The system of claim 18, wherein the processor is configured to determine that the property associated with energizing the actuation mechanism indicates that a fault condition exists when the processor determines that the property associated with energizing the actuation mechanism of each of a predetermined number of a set of prior pump strokes indicates the fault condition exists, or when the processor determines that the property associated with energizing the actuation mechanism of each of a predetermined number of consecutive pump strokes indicates the fault condition exists.

23. The system of claim 18, wherein the processor is further configured to initiate a recovery action to attempt to remedy the fault condition if it is determined that the property associated with energizing the actuation mechanism indicates the fault condition exists.

24. The system of claim 23, wherein the recovery action comprises a recovery sequence initiated by the processor.

25. The system of claim 23, wherein the recovery action comprises at least one of:

delivering a bolus of fluid through the medical pump;

increasing a drive voltage of the actuation mechanism;

increasing or decreasing a charge time of a capacitor that drives actuation mechanism, increasing a rate of pump strokes delivered by the medical pump, initiating a pump reset, and reinitializing the medical pump.

26. The system of claim 23, wherein the processor is further configured to determine whether the recovery action resolved the fault condition after initiating the recovery action.

27. The system of claim 18, wherein the property associated with energizing the actuation mechanism comprises at least one of:

a shape of at least a portion of an electrical current waveform through the actuation mechanism when the actuation mechanism is energized to provide a pump stroke;

a total energy supplied to the actuation mechanism in order to produce a pump stroke;

a voltage change across the actuation mechanism during a pump stroke;

an outlet fluid pressure of the medical pump.

28. The system of claim 18, wherein the property associated with energizing the actuation mechanism comprises a shape of at least a portion of an electrical current waveform through the actuation mechanism when the actuation mechanism is energized to provide a pump stroke, wherein the shape of the current waveform is defined by at least one of:

a time from a start of the current waveform to an initial peak current;

a change in time between the initial peak current and a subsequent nadir in the current waveform;

an amplitude value of the initial peak current;

a change in current value between the initial peak current and the subsequent nadir; and

a time from the start of the current waveform to a nadir indicating an end of a pump stroke.

29. The system of claim 18, wherein the property associated with energizing the actuation mechanism comprises a shape of at least a portion of an electrical current waveform through the actuation mechanism when the actuation mechanism is energized to provide a pump stroke, the method further comprising storing a baseline shape that indicates a normal pump stroke in a memory, determining a shape of at least a portion of an electrical current waveform through the actuation mechanism when the actuation mechanism is energized to provide a pump stroke, and comparing the baseline shape to the shape of the portion of the current waveform through the actuation mechanism to provide the pump stroke to determine if the fault condition exists.

30. The system of claim 18, wherein the sensor comprises at least one of a current sensor, a voltage sensor, or a pressure sensor.

31. The system of claim 18, wherein the processor is configured to initiate an alarm if it is determined that the property associated with energizing the actuation mechanism indicates the fault condition exists.

32. The system of claim 18, wherein the processor is configured to log a time stamp indicating the time at which the fault condition was determined to exist.

33. The system of claim 18, wherein the processor is configured to monitor the medical pump and determining if the fault condition has been resolved.

34. The system of claim 33, wherein the processor is configured to determine that the fault condition has been resolved when the processor determines that the property associated with energizing the actuation mechanism of each of a predetermined number of a set of prior pump strokes indicates that the fault has been resolved, or when the processor determines that the property associated with energizing the actuation mechanism of each of a predetermined number of consecutive pump strokes indicates that the fault condition has been resolved.

35. The system of claim 33, wherein the processor is configured to log a time stamp indicating the time at which the fault condition was resolved if the processor determines that the fault condition has been resolved.

36. The system of claim 33, wherein the processor is configured to initiate an alarm when the processor determines that the property associated with energizing the actuation mechanism indicates the fault condition exists and to clear the alarm when the processor determines that the fault condition has been resolved.

37. A medical device system comprising:

means for delivering a therapeutic fluid to a patient, the means for delivering the therapeutic fluid comprising means for actuating the fluid and to provide a pump stroke;

means for detecting a property associated with energizing the means for actuating the fluid; and

means for determining whether the property associated with the energizing the actuating the fluid indicates that a fault condition within the means for actuating the fluid exists.

38. The system of claim 37, wherein the means for actuating the fluid comprises a coil configured to be energized to provide a pump stroke and an actuator that is movable in response to the energization of the coil.

39. The system of claim 37, wherein the fault condition comprises one of a plurality of fault condition types, and wherein the processor is further configured to identify which of the plurality of fault condition types exists.

40. The system of claim 37, wherein the fault condition comprises at least one of:

a full stall of the means for actuating the fluid, a partial stall of the means for actuating the fluid, a high energy pump stroke, a low energy pump stroke, gas accumulation within the means for delivering the therapeutic fluid, air locking of the means for delivering the therapeutic fluid, voltage depletion of a means for providing energy to the means for actuating the fluid, blockage in a flow path of the means for delivering the therapeutic fluid, an electrical short in the actuation mechanism, and on open switch between the means for actuating the fluid and the means for providing energy to the means for actuating the fluid.

41. The system of claim 37, wherein the means for determining whether the property associated with the energizing the actuating the fluid is configured to determine when the property associated with energizing the means for actuating the fluid indicates that a fault condition exists when the means for determining whether the property associated with the energizing the actuating of the fluid determines that the property associated with energizing the means for actuating the fluid of each of a predetermined number of a set of prior pump strokes indicates the fault condition exists, or when the means for determining whether the property associated with the energizing the actuating of the fluid determines that the property associated with energizing the means for actuating the fluid of each of a predetermined number of consecutive pump strokes indicates the fault condition exists.

42. The system of claim 37, further comprising means for performing a recovery action to attempt to remedy the fault condition.

43. The system of claim 42, wherein the recovery action comprises a recovery sequence.

44. The system of claim 42, wherein the recovery action comprises at least one of:

delivering a bolus of fluid through the medical pump;

increasing a drive voltage of the actuation mechanism;

increasing or decreasing a charge time of a capacitor that drives actuation mechanism, increasing a rate of pump strokes delivered by the medical pump, initiating a pump reset, and reinitializing the medical pump.

45. The system of claim 37, wherein the property associated with energizing the means for actuating the fluid comprises at least one of:

a shape of at least a portion of an electrical current waveform through the means for actuating the fluid when the means for actuating the fluid is energized to provide a pump stroke;

a total energy supplied to the means for actuating the fluid in order to produce a pump stroke;

a voltage change across the means for actuating the fluid during a pump stroke;

an outlet fluid pressure of the means for delivering the therapeutic fluid.

46. The system of claim 37, wherein the property associated with energizing the means for actuating the fluid comprises a shape of at least a portion of an electrical current waveform through the means for actuating the fluid when the means for actuating the fluid is energized to provide a pump stroke, wherein the shape of the current waveform is defined by at least one of:

a time from a start of the current waveform to an initial peak current;

a change in time between the initial peak current and a subsequent nadir in the current waveform;

an amplitude value of the initial peak current;

a change in current value between the initial peak current and the subsequent nadir; and

a time from the start of the current waveform to a nadir indicating an end of a pump stroke.

47. The system of claim 37, wherein the property associated with energizing the means for actuating the fluid comprises a shape of at least a portion of an electrical current waveform through the means for actuating the fluid when the means for actuating the fluid is energized to provide a pump stroke, the method further comprising storing a baseline shape that indicates a normal pump stroke in a memory, determining a shape of at least a portion of an electrical current waveform through the means for actuating the fluid when the means for actuating the fluid is energized to provide a pump stroke, and comparing the baseline shape to the shape of the portion of the current waveform through the means for actuating the fluid to provide the pump stroke to determine if the fault condition exists.

48. The system of claim 37, further comprising means for initiating an alarm when it is determined that the property associated with energizing the means for actuating the fluid indicates the fault condition exists.

49. The system of claim 37, further comprising a means for logging a time stamp indicating the time at which the fault condition was determined to exist.

50. The system of claim 37, further comprising a means for monitoring the means for delivering a therapeutic fluid and determining if the fault condition has been resolved.

51. The system of claim 50 wherein the means for monitoring the means for delivering a therapeutic fluid is configured to determine whether the recovery action resolved the fault condition when the means for monitoring the means for delivering a therapeutic fluid determines that the property associated with energizing the actuating the fluid of each of a predetermined number of a set of prior pump strokes indicates that the fault has been resolved, or when the means for monitoring the means for delivering a therapeutic fluid determines that the property associated with energizing the actuating of the fluid of each of a predetermined number of consecutive pump strokes indicates that the fault condition has been resolved.

52. The system of claim 50, further comprising a means for logging a time stamp indicating the time at which the fault condition was resolved if the means for monitoring the means for delivering a therapeutic fluid determines that the fault condition has been resolved.

53. The system of claim 50, further comprising a means for initiating an alarm when the means for monitoring the means for delivering a therapeutic fluid determines that the property associated with energizing the actuating the fluid indicates the fault condition exists and means for clearing the alarm when the means for monitoring the means for delivering a therapeutic fluid determines that the fault condition has been resolved.

54. A computer-readable medium comprising instructions for causing a programmable processor to:

direct the delivery of a therapeutic fluid using a medical pump comprising an actuation mechanism configured to be energized to provide a pump stroke;

detect a property associated with energizing the actuation mechanism; and

determine whether the property associated with energizing the actuation mechanism indicates that a fault condition exists within the medical pump.