System for monitoring physiological characteristics

• US 20050038332A1
• Filed: 06/03/2004
• Published: 02/17/2005
• Est. Priority Date: 12/27/2001
• Status: Active Grant

• Current Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Minimed Incorporated (Medtronic Plc)
• Inventors: Mueller, John C. Jr., Saidara, Frank, Mastrototaro, John Joseph, Tolle, Charles Vallet, Nielsen, Edward S., Sanders, Jeff B.
• Granted Patent: US 7,399,277 B2
• Time in Patent Office: Days
• US Class Current: 600/347
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 2560/045 with a separable interface unit, e.g. for communication
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1468 using chemical or electrochemical methods, e.g. by polarographic means A61B5/1486 takes precedence
• CPC Class Codes: A61B 5/1486 using enzyme electrodes, e.g. with immobilised oxidase
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor
• CPC Class Codes: A61B 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B
• CPC Class Codes: G01N 33/48792 Data management, e.g. communication with processing unit for in vivo diagnostics A61B5/0002; transmission systems for measured values G08C
• CPC Class Codes: G16H 15/00 ICT specially adapted for medical reports, e.g. generation or transmission thereof
• CPC Class Codes: G16H 20/10 relating to drugs or medications, e.g. for ensuring correct administration to patients
• CPC Class Codes: G16H 20/17 delivered via infusion or injection
• CPC Class Codes: G16H 40/63 for local operation
• CPC Class Codes: G16H 40/67 for remote operation

Abstract

Apparatuses and methods for medical monitoring physiological characteristic values such as blood glucose levels for the treatment of diabetes, are presented. The apparatuses and methods provide for preventing any negative consequence in the operation of a monitor and/or infusion device as a result of disorientation that may occur from waking from slumber with a low blood glucose level. In addition, a graphical display is disclosed incorporating a variety of enhancements which readily conveys to the user historical as well as real time information regarding the measured characteristic value.

Claims

1. A device, comprising:

a sensor input capable of receiving a signal from a sensor, the signal being based on a sensed physiological characteristic value of a user of the device; and

a processor coupled to the sensor input for operating an alarm based on the received signal from the sensor;

wherein the processor activates the alarm according to;

a first criteria when the user is awake; and

a second criteria when the user is asleep.

2. The device of claim 1, wherein the sensed physiological characteristic is a measurement of glucose.

3. The device of claim 2, wherein the device provides an alarm warning at an earlier timepoint when the user is asleep as compared to when the user is awake by altering a threshold criteria for the activation an alarm during sleeping hours, wherein the threshold criteria includes:

glucose concentrations reaching a predetermined value;

or

glucose concentrations exhibiting a predetermined rate of change.

4. The device of claim 3, wherein providing earlier alarm warning to the user is applied to multiple alarms.

5. The device of claim 3, wherein activating the alarm to provide earlier alarm warning is performed by monitoring a rate of change in the sensed physiological characteristic value and adjusting an alarm threshold value when the rate exceeds a predetermined rate limit.

6. The device of claim 5, wherein the physiological characteristic value is a blood glucose measurement, providing earlier warning to the user is applied to a low blood glucose alarm and the rate limit comprises a declining blood glucose rate.

7. The device of claim 6, wherein the rate limit is between approximately −

2.0 mg/dl and approximately −

4.0 mg/dl.

8. The device of claim 3, wherein adjusting the alarm threshold criteria comprises raising a low blood glucose alarm threshold.

9. The device of claim 8, wherein the low blood glucose alarm threshold is raised by approximately 6 mg/dl.

10. The device of claim 8, wherein the low blood glucose alarm threshold is raised by approximately 12 mg/dl.

11. The device of claim 8, wherein the low blood glucose alarm threshold is raised by approximately 6 mg/dl and the rate limit is approximately −

2.0 mg/dl.

12. The device of claim 8, wherein the low blood glucose alarm threshold is raised by approximately 12 mg/dl the rate limit is approximately −

4.0 mg/dl.

13. The device of claim 1, wherein activating the alarm to provide earlier warning is set according to a schedule based on a time of day.

14. The device of claim 3, wherein activating the alarm to provide earlier warning is set by the user before sleeping.

15. The device of claim 1, wherein the processor delays accepting input from the user when the processor activates the alarm according to the second criteria.

16. A device, comprising:

a sensor input capable of receiving a signal from a sensor, the signal being based on a sensed physiological characteristic value of a user; and

a processor coupled to the sensor input for operating an alarm based on the sensed physiological characteristic value of the user from the received signal from the sensor;

wherein the processor activates the alarm and delays accepting input from the user when the alarm awakens the user.

17. The device of claim 16, wherein the physiological characteristic value is a blood glucose measurement and delaying accepting input from the user is applied to a low blood glucose alarm.

18. The device of claim 16, wherein the physiological characteristic value is a blood glucose measurement and delaying accepting input from the user is applied to a high blood glucose alarm.

19. The device of claim 16, wherein delaying accepting input from the user is applied to a plurality of alarms based on a plurality of sensed physiological characteristic values.

20. The device of claim 16, wherein delaying accepting input from the user is set according to a schedule based on a time of day.

21. The device of claim 16, wherein delaying accepting input from the user is set by the user before sleeping.

22. The device of claim 16, wherein the processor delays accepting input from the user until the user provides a predetermined input.

23. The device of claim 22, wherein the predetermined input comprises entering a numeric code or executing a button sequence.

24. The device of claim 16, wherein the processor activates the alarm to provide earlier warning to the user when sleeping than when the users is awake.

25. A device, comprising:

a sensor input capable of receiving a signal from a sensor, the signal being based on a sensed physiological characteristic value of a user;

a memory for storing a plurality of measurements of the sensed physiological characteristic value of the user from the received signal from the sensor; and

a display for presenting a graphical representation of the plurality of measurements of the sensed physiological characteristic value.

26. The device of claim 25, wherein the graphical representation displays real time measurements of the sensed physiological characteristic value.

27. The device of claim 25, wherein the received signal from the sensor is transmitted via RF telemetry.

28. The device of claim 25, wherein the device is an infusion pump.

29. The device of claim 25, wherein the physiological characteristic value is a blood glucose measurement.

30. The device of claim 25, wherein the physiological characteristic value measurement is displayed in a graphical format or a text format or a combination thereof.

31. The device of claim 25, wherein the graphical representation comprises a color coded set of indicators.

32. The device of claim 25, wherein the a graphical representation comprises one or more trend indicators, indicating an approximate rate trend in the sensed physiological characteristic value over a recent series of the plurality of measurements.

33. The device of claim 32, wherein the graphical representation comprises a vertical cursor which allows a user to alternatively select measurements of the sensed physiological characteristic value from the graphical format or from the text format.

34. The device of claim 32, wherein the recent series of the plurality of measurements comprises four most recent measurements.

35. The device of claim 32, wherein the one or more trend indicators includes an indicator of a current measurement.

36. The device of claim 32, wherein the one or more trend indicators comprise a color coded set of indicators.

37. The device of claim 36, wherein the physiological characteristic value is a blood glucose measurement and the color coded set of indicators comprises a grid of nine indicators including three rate trend categories including going down, stable and going up and three current measurement categories including low, in zone and high where a single rate trend category and a single current measurement category are indicated simultaneously.

38. The device of claim 37, wherein going down and low and going up and high are indicated in red;

going down and high and going up and low are indicated in yellow;

going down and in zone, going up and in zone, stable and high and stable and low are indicated in orange; and

stable and in zone is indicated in green.

39. The device of claim 32, wherein the one or more trend indicators comprise five symbols indicating a fast increasing rate, a moderate increasing rate, a negligible rate change, a moderate decreasing rate and a fast decreasing rate, respectively.

40. The device of claim 39, wherein the physiological characteristic value is a blood glucose measurement and the fast increasing rate is at least approximately +3 mg/dl, the moderate increasing rate is between approximately +3 mg/dl and +1 mg/dl, the negligible rate change is between approximately +1 mg/dl and −

1 mg/dl, the moderate decreasing rate is between approximately −

1 mg/dl and −

3 mg/dl and the fast decreasing rate equal or exceeding −

3 mg/dl.

41. The device of claim 39, wherein the five symbols comprise two up arrows, a single up arrow, no indicator, a single down arrow and two down arrows corresponding respectively to the fast increasing rate, the moderate increasing rate, the negligible rate change, the moderate decreasing rate and the fast decreasing rate.

42. The device of claim 25, wherein the physiological characteristic value is a blood glucose measurement and the graphical representation comprises a graphical plot of at least a portion of the plurality of measurements of the sensed blood glucose measurement where a horizontal axis comprises a time scale and a vertical axis comprises a blood glucose measurement scale.

43. The device of claim 42, wherein the graphical plot comprises a color coded set of indicators.

44. The device of claim 43, wherein the color coded set of indicators comprise horizontal bands corresponding to various levels of danger corresponding to each of the plurality of measurements of the sensed blood glucose measurement.

45. The device of claim 43, wherein the color coded set of indicators comprises a color of the graphical plot indicating a current danger level corresponding to a current blood glucose measurement.

46. The device of claim 42, wherein the graphical plot is continuously updated in real-time such that the shown portion of the plurality of measurements of the sensed blood glucose measurement comprises a most recent period.

47. The device of claim 42, wherein the blood glucose measurement scale can be selectively displayed in mg/dl or mmol/l.

48. The device of claim 42, wherein the blood glucose measurement scale comprises a fixed measurement range from approximately 0 to 310 mg/dl or approximately 0 to 17.2 mmol/l.

49. The device of claim 42, wherein the time scale comprises a time range selectively changed to show different periods of the plurality of blood glucose measurements.

50. The device of claim 49, wherein the time range is selectively changed as either a 3 hour period or a 24 hour period.

51. The device of claim 50, wherein when the time range shows the 3 hour period the graphical plot comprises approximately 36 blood glucose measurements, each approximately five minutes apart.

52. The device of claim 49, wherein when the time range shows the 3 hour period each hour of the graphical plot is marked by a vertical line.

53. The device of claim 49, wherein when the time range shows the 24 hour period the graphical plot comprises approximately 72 blood glucose measurements, each approximately 20 minutes apart.

54. The device of claim 49, wherein when the time range shows the 24 hour period the graphical plot daytime hours are displayed with a light background and night time hours are displayed with a dark background.

55. The device of claim 49, wherein when the time range shows the 24 hour period noon and midnight on the graphical plot are each marked by a vertical line.

56. A device, comprising:

a sensor input capable of receiving at least one signal from a sensor, the signal being based on a plurality of sensed physiological characteristic values of a user of the device; and

a processor coupled to the sensor input for operating a plurality of alarms based on the received signal from the sensor;

wherein the processor is capable of activating each of the plurality of alarms according to a different sensed physiological characteristic value of the plurality of sensed physiological characteristic values.

57. The device of claim 56, wherein the plurality of sensed physiological characteristic values include:

blood glucose concentrations in the user; and

the rate of change of blood glucose concentrations in the user over a predetermined time period.

58. The device of claim 57, wherein a first alarm is activated when glucose concentrations exhibit a predetermined rate of change and a second alarm is activated when glucose concentrations reach a predetermined value.

59. The device of claim 58, wherein the criteria for activating the first alarm are more stringent than the criteria for activating the second alarm.

60. The device of claim 58, wherein the processor is capable of activating an alarm based on an evaluation of both the blood glucose concentrations in the user and the rate of change of blood glucose concentrations.

61. The device of claim 60, wherein the alarm is activated based on a mathematical comparison of the blood glucose concentrations in the user and the rate of change of blood glucose concentrations in the user.

62. The device of claim 56, further including a relay that automatically dials a predetermined telephone number as part of a notification scheme for an event that has not been acknowledged and/or addressed by the user.