Oxygen monitoring apparatus and methods of using the apparatus

• US 20030190262A1
• Filed: 03/28/2003
• Published: 10/09/2003
• Est. Priority Date: 01/24/2001
• Status: Active Grant

• Current Assignee: RIC INVESTMENTS LLC (Koninklijke Philips N.V.)
• Original Assignee: RIC INVESTMENTS LLC (Koninklijke Philips N.V.)
• Inventors: Apperson, Jerry R., Blazewicz, Perry R., Mace, Leslie E.
• Granted Patent: US 7,833,480 B2
• Time in Patent Office: Days
• US Class Current: 422/94
• CPC Class Codes: G01N 2021/6432 Quenching
• CPC Class Codes: G01N 2021/7786 Fluorescence
• CPC Class Codes: G01N 21/6408 with measurement of decay time, time resolved fluorescence
• CPC Class Codes: G01N 21/783 for analysing gases
• CPC Class Codes: Y10T 436/207497 Molecular oxygen
• CPC Class Codes: Y10T 436/209163 Dissolved or trace oxygen or oxygen content of a sealed environment

Abstract

Apparatus or systems which employ luminescence-quenching to produce a signal indicative of oxygen concentration. Components of such systems include: (1) an airway adapter, sampling cell, or the like having a casing and a sensor which is excited into luminescence with the luminescence decaying in a manner reflecting the concentration of oxygen in gases flowing through the airway adapter or other flow device and is in intimate contact with a window in the casing; (2) a transducer which has a light source for exciting a luminescable composition in the sensor into luminescence, a light sensitive detector for converting energy emitted from the luminescing composition as that the composition is quenched into an electrical signal indicative of oxygen concentration in the gases being monitored, and a casing which locates the light source and detector in close physical proximity to the window but on the side thereof opposite the sensor; and (3) subsystems for maintaining the sensor temperature constant and the temperature of the window above condensation temperature and for processing the signal generated by the light sensitive detector. Airway adapters, sampling cells, and transducers for such systems are also disclosed.

Claims

1. A sampling device of a respiratory gas sensor comprising:

a housing;

a flow passage for receiving a sample, said flow passage being defined by said housing;

a luminescable material exposed to said flow passage and visible from an exterior of said housing; and

a temperature communication element operatively coupled to said housing and associated with said luminescable material so as to control a temperature of said luminescable material.

2. The sampling device of claim 1, further comprising:

a window formed through said housing, said luminescable material exposed to said exterior of said housing through said window.

3. The sampling device of claim 2, wherein said window comprises a support supporting said luminescable material.

4. The sampling device of claim 3, wherein said luminescable material is carried by a matrix, which is carried upon said window.

5. The sampling device of claim 4, wherein said matrix is porous.

6. The sampling device of claim 5, wherein said matrix comprises a membrane.

7. The sampling device of claim 4, further comprising:

a retention element adjacent said window and configured to receive at least an edge portion of said matrix.

8. The sampling device of claim 7, wherein said retention element comprises:

an aperture formed in said housing and configured to receive said window; and

said window.

9. The sampling device of claim 8, wherein said aperture receives at least an edge portion of said matrix and said window secures at least said edge portion within said aperture upon positioning of said window in said aperture.

10. The sampling device of claim 1, wherein said luminescable material is capable of emitting at least one wavelength of electromagnetic radiation that, upon exposure of said luminescable material to at least one analyzed substance, is quenched at a rate related to a quantity of said at least one analyzed substance.

11. The sampling device of claim 10, wherein said at least one analyzed substance comprises oxygen.

12. The sampling device of claim 10, wherein said quantity comprises at least one of a concentration of said at least one analyzed substance and a partial pressure of said at least one analyzed substance in a mixture comprising at least one gaseous component.

13. The sampling device of claim 1, wherein said temperature communication element comprises an annular member.

14. The sampling device of claim 1, wherein said temperature communication element is configured to maintain at least said luminescable material at a substantially constant temperature.

15. The sampling device of claim 1, wherein said temperature communication element is configured to prevent moisture from collecting on a contacted structure.

16. The sampling device of claim 1, wherein said temperature communication element is configured to be coupled with a temperature control element of a transducer with which said housing is configured to be coupled.

17. The sampling device of claim 1, wherein said temperature communication element comprises a temperature control element.

18. The sampling device of claim 1, wherein said housing is configured to be positioned along the length of a breathing circuit.

19. The sampling device of claim 1, wherein said housing comprises a housing of a sidestream sampling cell.

20. A respiratory gas sensor, comprising:

a sampling device, comprising;

a housing;

a flow passage for receiving a sample, said flow passage being defined by said housing;

a luminescable material exposed to said flow passage and visible from an exterior of said housing, luminescence of said luminescable material being quenchable upon exposure thereof to at least one analyzable substance; and

a temperature communication element in thermal communication with said luminescable material; and

a transducer configured for assembly with at least a portion of said sampling device, said transducer comprising;

a housing;

a source of at least one wavelength of electromagnetic radiation within said housing; and

a detector within said housing, said source and said detector being oriented toward said luminescable material upon placement of said sampling device and said transducer in an assembled relationship.

21. The respiratory gas sensor of claim 20, further comprising a window defined in said housing.

22. The respiratory gas sensor of claim 21, wherein said window carries at least one of said luminescable material and a matrix by which said luminescable material is carried.

23. The respiratory gas sensor of claim 22, wherein said temperature communication element contacts at least one of said window and said matrix.

24. The respiratory gas sensor of claim 20, wherein said luminescable material is capable of emitting at least one wavelength of electromagnetic radiation that, upon exposure of said luminescable material to at least one analyzed substance, is quenched at a rate related to a quantity of said at least one analyzed substance in said sample.

25. The respiratory gas sensor of claim 24, wherein said at least one analyzed substance comprises oxygen.

26. The respiratory gas sensor of claim 20, wherein said temperature communication element is configured to maintain at least said luminescable material at a substantially constant temperature.

27. The respiratory gas sensor of claim 20, wherein said temperature communication element comprises a temperature control element.

28. The respiratory gas sensor of claim 20, wherein said temperature communication element is configured to be operatively coupled with a temperature control element.

29. The respiratory gas sensor of claim 20, wherein said transducer further comprises:

a temperature control element that communicates with said temperature communication element upon placement of said sampling device and said transducer in said assembled relationship.

30. The respiratory gas sensor of claim 20, wherein at least one of said sampling device and said transducer comprises an interconnection element.

31. The respiratory gas sensor of claim 30, wherein said interconnection element is configured to prevent misalignment between said sampling device and said transducer.

32. The respiratory gas sensor of claim 20, wherein said sampling device is configured to be positioned along the length of a breathing circuit.

33. The respiratory gas sensor of claim 20, wherein said housing of said sampling device comprises a housing of a sidestream sampling cell.