OPTICAL SENSOR FOR MEASURING PHYSIOLOGICAL PROPERTIES

• US 20130046159A1
• Filed: 02/17/2012
• Published: 02/21/2013
• Est. Priority Date: 02/18/2011
• Status: Active Grant

• Current Assignee: Sotera Wireless Incorporated
• Original Assignee: Devin Mccombie
• Inventors: McCombie, Devin, Trommer, Gunnar, Moon, Jim, Clear, Scott, Groeli, Julian, Dhillon, Marshall
• Granted Patent: US 10,357,187 B2
• Time in Patent Office: Days
• US Class Current: 600/324
• CPC Class Codes: A61B 2560/0443 Modular apparatus
• CPC Class Codes: A61B 2562/146 for optical coupling
• 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

Abstract

The invention provides a physiological probe that comfortably attaches to the base of the patient'"'"'s thumb, thereby freeing up their fingers for conventional activities in a hospital, such as reading and eating. The probe, which comprises a separate cradle module and sensor module, secures to the thumb and measures time-dependent signals corresponding to LEDs operating near 660 and 905 nm. The cradle module, which contains elements subject to wear, is preferably provided as a disposable unit.

Claims

1. A physiological probe configured for securing to a subject'"'"'s digit, comprising:

a sensor module comprising

(a) electronic circuitry which comprises (i) at least one source of electromagnetic radiation, and (ii) a photodetector configured to detect radiation from the at least one source of electromagnetic radiation after it has interacted with the subject'"'"'s tissue, thereby acquiring data relating to at least one physiologic property of the subject, wherein the photodetector is operably connected to a connection cable for delivery of photodetector signals to an external processing unit, and

(b) a flexible enclosure providing a cover for the electronic circuitry, wherein the flexible enclosure comprises (i) at least one aperture through which the at least one source of electromagnetic radiation emits radiation for irradiating the subject'"'"'s tissue, (ii) at least one aperture through which the photodetector receives radiation after it has interacted with the subject'"'"'s tissue, and (iii) an aperture through which the connection cable passes; and

a cradle module comprising

(a) at least first and second rigid housing members mated to one another via a hinge region to form an approximately semicircular ring which is configured to releasably receive the sensor module, wherein the hinge region is configured to provide a range of adjustment in a diameter of the ring while physically constraining an included angle measured between the at least one source of electromagnetic radiation and the photodetector within a predetermined range.

2. A physiological probe according to claim 1, wherein the hinge is configured to accommodate a subject'"'"'s thumb at the level of the proximal phalanx for purposes of acquiring the data relating to at least one physiologic property of the subject.

3. A physiological probe according to claim 1, wherein the hinge is configured to accommodate a girth of between about 6.2 cm and about 7.4 cm.

4. A physiological probe according to claim 1, wherein the hinge region is a pivoting hinge formed by mating the first and second rigid housing members, and wherein the structure of the first and second rigid housing members constrains opening or closing of the hinge beyond the predetermined range when mated to one another via the pivoting hinge.

5. A physiological probe according to claim 1, wherein the predetermined range of the included angle measured between the source(s) of electromagnetic radiation and the photodetector is less than or equal to about 60°

.

6. A physiological probe according to claim 5, wherein the predetermined range of the included angle measured between the source(s) of electromagnetic radiation and the photodetector is between about 60°

and about 30°

.

7. A physiological probe according to claim 6, wherein the predetermined range of the included angle measured between the source(s) of electromagnetic radiation and the photodetector is between about 55°

and about 35°

.

8. A physiological probe according to claim 4, wherein, the hinge is configured such that a force applied to move the hinge beyond the predetermined range separates the first and second rigid housing members.

9. A physiological probe according to claim 1, wherein the sensor module comprises one or more hinge points in the flexible enclosure.

10. A physiological probe according to claim 9, wherein the sensor module comprises at least two hinge points in the flexible enclosure configured to provide three substantially planar sensor module surfaces when the sensor module is mated to the cradle module.

11. A physiological probe according to claim 1, wherein the surface of the sensor module and the surface of the cradle module which come into contact when the two modules are mated comprise corresponding registration structures configured to register the position of the sensor module in the cradle module.

12. A physiological probe according to claim 1, wherein the length of the cradle module is between about 1 cm and about 1.5 cm.

13. A physiological prove according to claim 1, wherein the cradle module is disposable.

14. A method of obtaining pulse oximetry signals from a subject, comprising:

affixing a physiological probe according to claim 1 to the palmar aspect of a digit of the subject at the level of the proximal phalanx, wherein the probe is positioned on the subject'"'"'s digit such that the source(s) of electromagnetic radiation, when energized, provide irradiation of tissues of the subject through the capillary, arterial, and soft tissue of the digit, and subsequently to the photodetector;

energizing the sources to irradiate the tissues of the subject; and

detecting photodetector signals at an external processing unit operably connected via the connection cable.

15. A method according to claim 14, further comprising calculating one or more of a blood pressure value, an SpO2 value, a pulse rate, a respiration cycle, and a photoplethysmograph waveform for the subject using the photodetector signals.

16. A method according to claim 14, comprising determining a blood pressure value for the subject using the photodetector signals.

17. A cradle module adapted for use in a physiological probe, comprising:

at least first and second rigid housing members mated to one another via a pivoting hinge to form an approximately semicircular ring which is configured to releasably attach to a sensor module, the sensor module comprising (i) one or more sources of electromagnetic radiation, and (ii) a photodetector configured to detect the radiation from the sources which has passed through or been reflected by the subject'"'"'s tissue,

wherein the hinge is configured to provide a range of adjustment in the diameter of the ring while physically constraining the included angle measured between the source(s) of electromagnetic radiation and the photodetector within a predetermined range.

18. A cradle module according to claim 17, wherein the hinge is configured to accommodate a subject'"'"'s thumb at the level of the proximal phalanx for purposes of acquiring the data relating to at least one physiologic property of the subject.

19. A cradle module according to claim 17, wherein the hinge is configured to accommodate a girth of between about 6.2 cm and about 7.4 cm.

20. A cradle module according to claim 17, wherein the hinge region is a pivoting hinge formed by mating the first and second rigid housing members, and wherein the structure of the first and second rigid housing members constrains opening or closing of the hinge beyond the predetermined range when mated to one another via the pivoting hinge.

21. A cradle module according to claim 17, wherein the predetermined range of the included angle measured between the sources and the photodetector is less than or equal to about 60°

22. A cradle module according to claim 21, wherein the predetermined range of the included angle measured between the sources and the photodetector is between about 60°

and about 30°

.

23. A cradle module according to claim 22, wherein the predetermined range of the included angle measured between the sources and the photodetector is between about 55°

and about 35°

.

24. A cradle module according to claim 17, wherein, the hinge is configured such that a force applied to move the hinge beyond the predetermined range separates the first and second rigid housing members.

25. A cradle module according to claim 17, wherein the surface of the cradle module which comes into contact with the sensor module when the two modules are mated comprises registration structures configured to register the position of the sensor module in the cradle module.

26. A cradle module according to claim 17, wherein the length of the cradle module is between about 1 cm and about 1.5 cm.