Site selection for determining analyte concentration in living tissue

• US 20030040683A1
• Filed: 07/03/2002
• Published: 02/27/2003
• Est. Priority Date: 07/06/2001
• Status: Abandoned Application

• Current Assignee: OptiScan Biomedical Corporation
• Original Assignee: Hercules Technology Growth Capital, Inc.
• Inventors: Braig, James R., Hartstein, Philip C., Rule, Peter, Goldberger, Daniel S., Witte, Kenneth G., Cortella, Julian M., Agostino, Mark D., Smith, Heidi M., Herrera, Roger O.
• Application Number:
  US10/189,978
• Publication Number:
  US 20030040683A1
• Time in Patent Office: Days
• US Class Current: 600/584
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/1491 Heated applicators
• CPC Class Codes: A61B 5/6824 Arm or wrist
• CPC Class Codes: A61B 5/6826 Finger
• CPC Class Codes: A61B 5/6838 Clamps or clips

Abstract

A device and method for selecting and stabilizing proper sites for the measurement of the concentration of an analyte, for example glucose, within the tissue of a subject or patient are disclosed. One embodiment of the device immobilizes the subject'"'"'s forearm and finger, thereby stabilizing measurement sites thereon for exposure to a noninvasive monitor which captures analyte concentration data within the subject'"'"'s skin. The method involves the choice of a location on the subject'"'"'s body at which to take the analyte measurement, preferably based on the amount of time that has elapsed since the last time the subject ate.

Claims

1. A method of determining a location on a subject'"'"'s body whereat analyte measurements may be taken, based on the amount of elapsed time after the subject has eaten, said method comprising:

selecting an on-site location and an alternative site, said on-site location and said alternative site comprising distinct areas on said subject'"'"'s body;

establishing a relationship between a restricted time period and said on-site location and between an unrestricted time period and said alternative site, said restricted time period commencing immediately after said subject eats, said unrestricted time period commencing immediately after said restricted time period terminates; and

determining whether said amount of elapsed time after said subject has eaten falls within during said restricted time period; and

restricting said subject to taking analyte measurements at said on-site location during the restricted time period.

2. The method of claim 1, further comprising permitting said subject to take analyte measurements at either said on-site location or said alternative site during said unrestricted time period.

3. The method of claim 2, wherein said alternative site is a forearm.

4. The method of claim 2, wherein said alternative site is a palm.

5. The method of claim 1, wherein said on-site location is a finger.

6. The method of claim 5, wherein said on-site location is a fingertip.

7. The method of claim 1, wherein said restricted time period is about 2.0 hours.

8. The method of claim 1, wherein said restricted time period lasts between about 0.5 hours and about 3 hours after said subject last ate.

9. The method of claim 1, wherein said restricted time period lasts between about 1.0 hours and about 2.0 hours after said subject last ate.

10. The method of claim 1, wherein said restricted time period lasts between about 1.5 hours and about 2.0 hours after said subject last ate.

11. A method of measuring analyte concentration within the living tissue of a subject at a measurement location on the body of said subject, said method comprising:

designating a restricted time period and an unrestricted time period, said restricted time period commencing immediately after said subject eats, said unrestricted time period commencing immediately after said restricted time period terminates;

selecting only an on-site measurement location during a restricted time period; and

selecting any of an on-site measurement location and an alternative-site measurement location during an unrestricted time period.

12. The method of claim 11, further comprising performing an analyte concentration measurement at the selected measurement site.

13. The method of claim 12, further comprising augmenting local circulation near the selected measurement site.

14. The method of claim 11, wherein performing an analyte concentration measurement comprises performing an invasive analyte concentration measurement.

15. The method of claim 14, wherein performing an invasive analyte concentration measurement comprises drawing a blood sample from said subject and determining analyte concentration in said blood sample.

16. The method of claim 11, wherein performing an analyte concentration measurement comprises performing a noninvasive analyte concentration measurement.

17. The method of claim 16, wherein performing a noninvasive measurement comprises using an optical measurement system.

18. The method of claim 17, wherein said optical measurement system comprises a thermal gradient spectrometer which detects infrared energy emitted and/or reflected by said subject'"'"'s tissue to determine said analyte concentration based on the amount of infrared energy absorbed by the analyte.

19. The method of claim 11, wherein performing an analyte concentration measurement comprises performing an invasive analyte concentration measurement only at one of said on-site measurement location and said alternative-site measurement location, and performing a noninvasive analyte concentration measurement only at the other of said on-site measurement location and said alternative-site measurement location.

20. The method of claim 11, wherein said alternative-site measurement location is a forearm.

21. The method of claim 11, wherein said on-site measurement location is a finger.

22. The method of claim 21, wherein said on-site location is a fingertip.

23. The method of claim 21, wherein said alternative site is a palm.

24. The method of claim 11, wherein said restricted time period is about 2.0 hours.

25. The method of claim 11, wherein said restricted time period lasts between about 0.5 hours and about 3 hours after said subject last ate.

26. The method of claim 11, wherein said restricted time period lasts between about 1.0 hours and about 2.0 hours after said subject last ate.

27. The method of claim 11, wherein said restricted time period lasts between about 1.5 hours and about 2.0 hours after said subject last ate.

28. A mechanical stabilization device for immobilizing a finger and/or a hand for exposure to a blood constituent monitor, said device comprising:

a base comprising an elbow channel and a forearm channel for respectively stabilizing an elbow and a forearm of an arm such that relative movement between said arm and said base is substantially minimized, said forearm channel including a primary window configured for thermal contact with said forearm; and

a finger restraint comprising a finger hole which includes a secondary window configured for thermal contact with said finger.

29. The device of claim 28, wherein said primary window is configured to interface with said blood constituent monitor, said primary window facilitating capturing of analyte concentration data within tissue of said forearm.

30. The device of claim 28, wherein said secondary window is configured to interface with said blood constituent monitor, said secondary window facilitating capturing of analyte concentration data within tissue of said finger.

31. The device of claim 28, wherein said elbow channel and said forearm channel respectively conform to the anatomical shapes of said elbow and said forearm of said arm.

32. The device of claim 28, wherein said finger restraint conforms to the anatomical shape of said finger.

33. The device of claim 28, wherein said base further comprises a pair of forearm restraining holes and a pair of elbow restraining holes, said forearm restraining holes and said elbow restraining holes facilitating stabilizing said arm within said base.

34. The device of claim 28, wherein said finger restraint is movable distally and proximally relative said forearm channel to accommodate various forearms and fingers having different lengths.

35. The device of claim 28, wherein said finger hole has a diameter which may be increased and decreased so as to stabilize a variety of fingers having different sizes.

36. A method for stabilizing an arm and a finger of a subject for determination of analyte concentration within said subject'"'"'s tissue, said method comprising:

providing a mechanical stabilization device comprising a base and a finger restraint, said base comprising an elbow channel and a forearm channel for stabilizing said arm, said forearm channel including a primary window configured for thermal contact with said forearm, said finger restraint comprising a finger hole which includes a secondary window;

inserting said finger into said finger hole while said forearm is laid onto the forearm channel and said elbow is placed within the elbow channel;

securing said forearm within said forearm channel and securing said elbow within said elbow channel, such that said forearm is placed into thermal contact with said primary window;

tightening said finger hole around said finger such that said finger is placed into thermal contact with said second window; and

performing said determination of analyte concentration within said subject'"'"'s tissue.

37. The method of claim 36, wherein said finger hole has an adjustable diameter which can be increased and decreased so as to tighten around and release said finger.

38. The method of claim 36, wherein said securing said forearm further comprises passing a forearm fastening strap over said forearm and through a pair of forearm fastening holes within said base, said fastening strap tightened to prevent relative movement between said forearm and said forearm channel.

39. The method of claim 36, wherein said securing said elbow further comprises passing an elbow fastening strap over a proximal portion of said forearm and through a pair of elbow fastening holes within said base, said fastening strap tightened to prevent relative movement between said elbow and said elbow channel.

40. A mechanical stabilization device for use with a monitor for determining analyte concentration within tissue of a subject, said device comprising:

a first site selector forming a thermal interface between a window of said monitor and an on-site location of said tissue; and

a second site selector forming a thermal interface between said window of said monitor and an alternate site on said tissue, said on-site location and said alternate site comprising two distinct locations on said tissue of said subject.

41. The device of claim 40, wherein said first site selector is smaller than said second site selector.

42. The device of claim 41, further comprising an adaptive member which facilitates coupling said first site selector with said monitor.

43. The device of claim 40, wherein said alternate site is a forearm.

44. The device of claim 40, wherein said on-site location is a finger.

45. The device of claim 40, wherein said first and second site selectors each comprises a generally flat member having an aperture which allows thermal spectra to pass therethrough.

46. The device of claim 45, wherein said first and second site selectors each interfaces with a window of said monitor.

47. The device of claim 40, wherein said first and second site selectors are each made of a flexible, semi-compliant material which allows said first and second site selectors to bend thereby conforming to various location on said subject.

48. The device of claim 40, wherein said first and second site selectors each comprises a window having a heating element disposed thereon, each of said windows comprising a material of high thermal conductivity so as to permit thermal spectra to pass therethrough.

49. The device of claim 48, wherein said first and second site selectors are each electrically connected to an external power supply.

50. The device of claim 48, wherein a power cable places said first site selector in electrical communication with said second site selector whereby said first site selector receives electric power when said second site selector is connected to said external power supply.

51. The device of claim 40, wherein fastening straps are used to attach said first and second site selectors to said tissue of said subject.