Medical sensor for reducing motion artifacts and technique for using the same

• US 20070073121A1
• Filed: 09/29/2005
• Published: 03/29/2007
• Est. Priority Date: 09/29/2005
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Nellcor Puritan Bennett LLC (Medtronic Plc)
• Inventors: Hoarau, Carine, Karst, Edward, Baker, Clark
• Granted Patent: US 7,869,850 B2
• Time in Patent Office: Days
• US Class Current: 600/323
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/6826 Finger
• CPC Class Codes: A61B 5/6838 Clamps or clips
• CPC Class Codes: A61B 5/6844 Monitoring or controlling distance between sensor and tissue
• CPC Class Codes: A61B 5/6886 Monitoring or controlling distance between sensor and tissue
• CPC Class Codes: Y10T 29/49826 Assembling or joining

Abstract

A sensor for pulse oximetry or other applications utilizing spectrophotometry may be adapted to reduce motion artifacts by fixing the optical distance between an emitter and detector. A flexible sensor is provided with a stiffening member to hold the emitter and detector of the sensor in a relatively fixed position when applied to a patient. Further, an annular or partially annular sensor is adapted to hold an emitter and detector of the sensor in a relatively fixed position when applied to a patient. A clip-style sensor is provided with a spacer that controls the distance between the emitter and detector.

Claims

1. A sensor comprising:

a sensor body; and

an emitter and a detector disposed on the sensor body, wherein the emitter and the detector are adapted to operate in a transmission mode, and wherein the sensor body is adapted to hold the emitter and detector at a substantially fixed optical distance relative to one another when the sensor is applied to a patient.

2. The sensor, as set forth in claim 1, wherein the sensor comprises at least one of a blood constituent sensor or a tissue constituent sensor.

3. The sensor, as set forth in claim 1, wherein the sensor comprises at least one of a pulse oximetry sensor or a sensor for measuring a water fraction.

4. The sensor, as set forth in claim 1, wherein the sensor comprises at least one of a carboxyhemoglobin sensor or a methemoglobin sensor.

5. The sensor, as set forth in claim 1, wherein the sensor is adapted for intrauterine use.

6. The sensor, as set forth in claim 1, wherein the emitter comprises at least one light emitting diode.

7. The sensor, as set forth in claim 1, wherein the detector comprises at least one photodetector.

8. The sensor, as set forth in claim 1, wherein the sensor body is conformable, and wherein the sensor comprises a stiffening member adapted to reversibly hold the emitter and the detector at the fixed optical distance.

9. The sensor, as set forth in claim 8, wherein the sensor body comprises a cavity adapted to receive the stiffening member.

10. The sensor, as set forth in claim 8, wherein the sensor body comprises one or more deformable chambers, wherein the one or more chambers are adapted to receive the stiffening member.

11. The sensor, as set forth in claim 8, wherein the stiffening member is embedded within the sensor body.

12. The sensor, as set forth in claim 8, wherein the stiffening member comprises a sleeve.

13. The sensor, as set forth in claim 8, wherein the stiffening member comprises a gel, liquid, gas, or foam.

14. The sensor, as set forth in claim 8, wherein the stiffening member comprises a metal or a rigid polymeric material.

15. The sensor, as set forth in claim 8, wherein the stiffening member is activated by exposure to a specific condition.

20. The sensor, as set forth in claim 1, wherein the sensor comprises a clip-style sensor.

21. The sensor, as set forth in claim 20, wherein the clip-style sensor comprises a spacer.

22. The sensor, as set forth in claim 21, wherein the spacer comprises a magnet.

23. The sensor, as set forth in claim 21, wherein the spacer is adjustable.

16-19. -19. (canceled)

24. A sensor comprising:

a conformable sensor body;

an emitter and a detector disposed on the conformable sensor body, wherein the emitter and the detector are adapted to operate in a reflectance mode; and

a stiffening member, wherein the stiffening member is disposed on the conformable sensor body proximate to the emitter and the detector, and wherein the stiffening member holds the emitter and the detector at a substantially fixed optical distance relative to one another when the sensor is applied to a patient.

25. The sensor, as set forth in claim 24, wherein the stiffening member is activated by exposure to a specific condition.

26. The sensor, as set forth in claim 24, wherein the sensor comprises at least one of a pulse oximetry sensor or a sensor for measuring a water fraction.

27. The sensor, as set forth in claim 24, wherein the sensor comprises at least one of a carboxyhemoglobin sensor or a methemoglobin sensor.

28. The sensor, as set forth in claim 24, wherein the sensor is adapted for intrauterine use.

29. The sensor, as set forth in claim 24, wherein the emitter comprises at least one light emitting diode.

30. The sensor, as set forth in claim 24, wherein the detector comprises at least one photodetector.

31. The sensor, as set forth in claim 24, wherein the sensor body comprises a cavity adapted to receive the stiffening member.

32. The sensor, as set forth in claim 24, wherein the sensor body comprises one or more deformable chambers, wherein the one or more chambers are adapted to receive the stiffening member.

33. The sensor, as set forth in claim 24, wherein the stiffening member is embedded within the sensor body.

34. The sensor, as set forth in claim 24, wherein the stiffening member comprises a gel, liquid, gas, or foam.

35. The sensor, as set forth in claim 24, wherein the stiffening member is activated by exposure to a specific condition.

36. The sensor, as set forth in claim 24, wherein the stiffening member comprises a metal or a rigid polymeric material.

37. A pulse oximetry system comprising:

a pulse oximetry monitor; and

a pulse oximetry sensor adapted to be operatively coupled to the monitor, the sensor comprising;

a sensor body;

an emitter and a detector disposed on the sensor body, wherein the sensor is adapted to hold the emitter and detector at a substantially fixed optical distance relative to one another when the sensor is applied to a patient.

38. The system, as set forth in claim 37, wherein the emitter and the detector are adapted to operate in transmission mode.

39. The system, as set forth in claim 37, wherein the emitter and the detector are adapted to operate in reflectance mode.

40. The system, as set forth in claim 37, wherein the sensor comprises at least one of a blood constituent sensor or a tissue constituent sensor.

41. The system, as set forth in claim 37, wherein the sensor comprises at least one of a pulse oximetry sensor or a sensor for measuring a water fraction.

42. The system, as set forth in claim 37, wherein the sensor comprises at least one of a carboxyhemoglobin sensor or a methemoglobin sensor.

43. The system, as set forth in claim 37, wherein the sensor is adapted for intrauterine use.

44. The system, as set forth in claim 37, wherein the emitter comprises at least one light emitting diode and wherein the detector comprises at least one photodetector.

45. The system, as set forth in claim 37, wherein the sensor body is conformable, and wherein the sensor comprises a stiffening member adapted to reversibly hold the emitter and the detector at a fixed optical distance when applied to a patient.

46. The system, as set forth in claim 45, wherein the sensor body comprises a cavity adapted to receive the stiffening member.

47. The system, as set forth in claim 45, wherein the sensor body comprises one or more deformable chambers, wherein the chambers are adapted to receive the stiffening member.

48. The system, as set forth in claim 45, wherein the stiffening member is embedded within the conformable sensor body.

49. The system, as set forth in claim 45, wherein the stiffening member comprises a sleeve.

50. The system, as set forth in claim 45, wherein the stiffening member comprises a gel, liquid, gas, or foam.

51. The system, as set forth in claim 45, wherein the stiffening member comprises a metal or a rigid polymeric material.

56. The system, as set forth in claim 37, wherein the sensor comprises a clip-style sensor.

57. The system, as set forth in claim 56, wherein the clip-style sensor comprises a magnet.

58. The system, as set forth in claim 56, wherein the clip-style sensor comprises a spacer.

59. The system, as set forth in claim 56, wherein the spacer is adjustable.

52-55. -55. (canceled)

60. A method comprising:

fixing the optical distance between an emitter and a detector relative to one another, wherein the emitter and the detector are disposed on a sensor body.

61. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises inserting the stiffening member into a cavity in the sensor body.

62. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises inserting the stiffening member into one or more deformable chambers in the sensor body.

63. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises embedding a stiffening member within the sensor body.

64. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises sliding a sleeve around the sensor.

65. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises inserting a gel, liquid, gas, or foam stiffening member into the sensor body.

66. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises inserting a metal or a rigid polymeric material stiffening member into the sensor body.

67. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises disposing the emitter and the detector on a substantially annular or partially annular sensor body, wherein the sensor body is adapted for use on a patient'"'"'s digit.

68. The method, as set forth in claim 63, wherein fixing the optical distance between the emitter and the detector comprises adjusting the diameter of the sensor body with an adjustment strap.

69. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises engaging a spacer on the sensor body, wherein the sensor body comprises a clip.

70. The method, as set forth in claim 60, wherein fixing the optical distance between the emitter and the detector comprises engaging a magnet on the spacer.

71. A method of manufacturing a pulse oximetry sensor, comprising:

providing a sensor body on which an emitter and a detector are disposed, wherein the sensor body is adapted to hold the emitter and the detector at a substantially fixed optical distance.

72. The method, as set forth in claim 71, comprising:

providing the sensor body, wherein the sensor body is conformable; and

providing a stiffening member, wherein the stiffening member is adapted to reversibly hold the emitter and the detector at the substantially fixed optical distance.

73. The method, as set forth in claim 72, comprising:

embedding the stiffening member within the sensor body.

74. The method, as set forth in claim 72, comprising:

forming the stiffening member into a sleeve.

75. The method, as set forth in claim 72, comprising:

forming a cavity in the sensor body

76. The method, as set forth in claim 72, comprising:

forming one or more deformable chambers in the sensor body.

80. The method, as set forth in claim 71, comprising:

providing a clip-style sensor.

81. The method, as set forth in claim 80, comprising:

providing a spacer.

82. The method, as set forth in claim 80, comprising:

providing a magnet on the spacer.

83. The method, as set forth in claim 80, comprising:

providing an adjustable spacer.

77-79. -79. (canceled)