System and method for continuous monitoring of diabetes-related blood constituents

• US 5,741,211 A
• Filed: 10/26/1995
• Issued: 04/21/1998
• Est. Priority Date: 10/26/1995
• Status: Expired due to Term

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Renirie, Alexis C. M., Houben, Richard, van Leeuwen, Frank
• Primary Examiner(s): Bahr, Jennifer
• Assistant Examiner(s): YARNELL, BRYAN KEITH
• Application Number:
  US08/548,784
• Time in Patent Office: 908 Days
• Field of Search: 128/630, 128/668, 128/670, 128/696, 128/700, 128/695, 128/702, 128/703, 128/705, 128/920, 607/6, 607/72, 607/22, 607/25
• US Class Current: 600/300
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: Y10S 128/92 Computer assisted medical diagnostics

Abstract

A system and method for sensing and providing an indication of one or more diabetes-related blood constituents of a patient, the system being based upon an ECG sensor which processes patient ECG signals, either surface, or intracardiac or epicardial, for determining a measure of a blood constituent such as insulin or glucose, or both insulin and glucose. The system has processing capability for correlating selected parameters of the ECG signal with patient blood insulin or blood glucose, to provide the insulin or glucose level. Additionally, the system is provided with input capability for enabling the patient to input data such as the time of meal intake, which is representative of glucose intake, which data is incorporated in making a determination of patient insulin need. The system can be in a first external wearable embodiment, or in a second implantable embodiment which utilizes a pacing-type lead for picking up intracardiac or epicardial signals. In either the wearable or implantable embodiment, the output response may be simply an indication of patient insulin and/or glucose need provided by an external display, and may also include automatic control of insulin injection to the patient.

Claims

1. System apparatus for providing an indication of at least patient blood insulin, comprising:

ECG sensor means for obtaining signals representative of the patient ECG,

signal processing means for processing said ECG signals to provide first parameter data indicative of the patient'"'"'s blood insulin level, wherein the signal processing means include means for comparing the sensed ECG signals against a reference value, and

response means for providing a response as a function of said data.

2. The system apparatus as described in claim 1, wherein said response means comprises means for outputting an indication of the patient'"'"'s blood insulin level.

3. The system apparatus as described in claim 1, wherein said system apparatus is implantable in said patient and said response means comprises pump means for injecting insulin into said patient as a function of said insulin data.

4. The system apparatus as described in claim 1, comprising a wearable housing for housing said apparatus and adapted to be worn by a patient, and wherein said response means comprises output means for providing an output signal receivable by said patient, said output signal being representative of the patient'"'"'s insulin level.

5. The system apparatus as described in claim 1, wherein said signal processing means further comprises glucose means for processing said ECG signals and obtaining second parameter data indicative of the patient blood glucose level.

6. The system apparatus as described in claim 5, wherein said signal processing means further comprises analyzing means for analyzing said insulin and glucose data, and additional response means for providing a response as a function of said analyzed insulin and glucose data.

7. The system apparatus as described in claim 1, comprising keyboard input means for inputting data representative of patient glucose intake.

8. A system for providing an indication of blood insulin level of a patient, comprising

ECG sensor means for sensing ECG signals of said patient,

processing means for processing said ECG signals and obtaining therefrom a measure of patient blood insulin, wherein the processing means include means for comparing the sensed ECG against a reference value, and

output means responsive to said insulin measure for outputting an indication of patient insulin level.

9. The system as described in claim 8, comprising an implantable housing for housing said system within said patient.

10. The system as described in claim 8, wherein said signal processing means comprises parameter means for separating out predetermined parameters of said patient ECG which correlate to patient blood insulin level.

11. The system as described in claim 8, comprising storage means for storing patient blood insulin levels, and wherein said signal processing means further comprises extrapolation means for extrapolating anticipated time of insulin need as a function of said stored patient blood insulin levels.

12. The system as described in claim 8, further comprising second processing means for processing said ECG signals and obtaining therefrom an indication of patient blood glucose.

13. The system as described in claim 12, further comprising delivery means for delivering insulin to the patient, and control means for controlling said delivery means to provide indicated insulin in response to indicated patient insulin and glucose levels.

14. A system for determining insulin need of a diabetic patient, comprising

ECG sensing means for sensing the patient ECG and deriving therefrom an indication of patient blood insulin level,

glucose input means for inputting data indicative of patient glucose intake,

processing means for determining patient insulin need as a function of said indicated blood insulin level and said glucose intake data, wherein the processing means include means for comparing said indicated blood insulin level against a reference value, and

response means for outputting an indication of said determined patient insulin need.

15. The system as described in claim 14, wherein said ECG sensing means comprises first processing means for processing ECG signals and deriving therefrom selected parameter data.

16. The system as described in claim 15, wherein said ECG sensing means comprises second processing means for determining time variations of selected ECG parameters and for calculating anticipated insulin need as a function of said variations.

17. The system as described in claim 14, wherein said glucose input means comprises an input terminal adapted to enable said patient to enter said glucose intake data.

18. The system as described in claim 17, wherein said input means comprises time means for storing data representative of the time of patient glucose intake.

19. The system as described in claim 14, wherein said processing means comprises glucose variation means for calculating anticipated glucose variation as a function of said glucose intake data, and wherein said response means comprises comparing means for comparing anticipated glucose variation with measured patient insulin level.

20. The system as described in claim 14, comprising second processing means for processing said ECG signals to obtain a measure of patient glucose, and wherein said response means comprises dual parameter response means for responding as a function of determined insulin and glucose levels.

21. A system for sensing one or more diabetes-related blood constituents of a patient, comprising an implantable apparatus and an external apparatus, said implantable apparatus comprising sensor means for continuously sensing ECG signals from said patient;

processing means for continuously processing said ECG signals and obtaining therefrom data indicating the level of at least one selected blood constituent, wherein the processing means include means for comparing the sensed ECG signals against a reference value; and

transfer means for transferring said data to said external apparatus, and

said external apparatus comprising indicator means for indicating said patient blood constituent level based upon said transferred data.

22. The system as described in claim 21, wherein said at least one selected blood constituent is blood insulin, and said data is insulin data, and said indicating means comprises display means for displaying a measure of patient blood insulin.

23. The system as described in claim 22, comprising external data transfer means for transferring data from said external apparatus to said implanted apparatus, and wherein said implanted apparatus comprises receiving means for receiving said data transferred from said external apparatus.

24. The system as described in claim 23, wherein said external transfer means comprises means for transferring data representative of patient glucose intake.

25. The system as described in claim 24, wherein said implanted apparatus comprises processing means for processing said insulin data and said glucose intake data, and response means for delivering insulin to said patient based on said insulin data and said glucose data.

26. The system as described in claim 25, wherein said response means comprises an insulin pump for injecting insulin directly into said patient'"'"'s body.

27. The system as described in claim 23, wherein said external apparatus comprises input means for inputting data representative of patient glucose intake and transfer means for transferring said glucose intake data to said implantable apparatus, said implantable apparatus having receiving means for receiving said transferred glucose intake data.

28. The system as described in claim 21, wherein said blood constituent is glucose and said data is blood glucose data, and said indicating means comprises display means for displaying a measure of patient blood glucose.

29. The system as described in claims 28, comprising validity means for storing data indicative of whether said ECG signals correlate with blood glucose for said patient.

30. The system as described in claim 21, wherein said sensor means comprises means for sensing patient intracardiac signals.

31. The system as described in claim 21, wherein said sensor means comprises means for sensing patient epicardial signals.

32. The system as described in claim 21, wherein said processing means comprises VCG means for deriving the patient VCG from said ECG signals.

33. A system for continuously determining a measure of at least one diabetes-related blood constituent of a patient, said constituent selected from the group of blood insulin and blood glucose, comprising:

sense means for continuously sensing patient ECG signals, the ECG having a QRS portion and a T wave portion;

programmable means for storing data reflective of preselected ECG parameters corresponding to a selected one of said blood constituents;

first signal processing means for substantially continuously extracting from said ECG signals portions representative of said ECG parameters;

second signal processing means for processing said extracted signal portions and obtaining data therefrom which correlates with said selected constituent; and

third signal processing means for continuously determining a measure of said selected constituent as a function of said obtained data wherein said third signal processing means include means for comparing said obtained data against a reference value.

34. The system as described in claim 33, comprising a housing for containing said system whereby said system is adapted to be wearable by a patient.

35. The system as described in claim 33, comprising external means for programming said ECG parameters.

36. The system as described in claim 33, wherein said sense means comprises subcutaneous electrodes.

37. The system as described in claim 33, wherein said first signal processing means comprises averaging means for beat-to-beat averaging over a predetermined number of consecutive patient cardiac beats.

38. The system as described in claim 33, wherein said second signal processing means comprises means for determining from said extracted signals a measure of at least one of the QRS and the T wave portions of said patient ECG signals.

39. The system as described in claim 38, wherein said determining means comprises means for getting a measure of a RMS value of both said QRS and the T wave portions.

40. The system as described in claim 33, wherein said sense means has means for sensing intracardiac patient ECG signals.

41. The system as described in claim 38, further comprising means for storing basal values of preselected ECG parameters, and wherein said determining means comprises statistical means for comprising said determined parameter values with corresponding stored basal values.

42. The system as described in claim 33, wherein said at least one diabetes-related constituent is patient blood insulin, and comprising output means for providing an output representative of patient blood insulin.

43. The system as described in claim 33, wherein said at least one diabetes-related constituent is patient blood glucose, and comprising output means for providing an output representative of patient blood glucose.

44. The system as described in claim 33, wherein said at least one diabetes-related constituent is blood glucose, and further comprising validity means for enabling determination of patient blood glucose.