Ear canal pulse/oxygen saturation measuring device

• US 5,213,099 A
• Filed: 09/30/1991
• Issued: 05/25/1993
• Est. Priority Date: 09/30/1991
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: United States Of America As Represented By The Secretary Of The Air Force
• Inventors: Tripp, Lloyd D. Jr.
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): PONTIUS, KEVIN LANE
• Application Number:
  US07/767,969
• Time in Patent Office: 603 Days
• Field of Search: 128/633, 128/664, 128/665, 356/41, 356/39
• US Class Current: 600/324
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/6817 Ear canal
• CPC Class Codes: H01L 2224/29144 Gold [Au] as principal constituent
• CPC Class Codes: H01L 2924/0105 Tin [Sn]

Abstract

An improved apparatus and method for non-invasive monitoring of blood oxygen saturation and pulse is made by modifying a conventional prior art pulse oximeter probe for use inside an ear canal or other body cavity. This placement is particularly useful for unobtrusively monitoring the blood oxygen saturation and pulse of pilots flying high performance military aircraft. When monitored blood oxygen saturation or pulse levels fall to a level indicating imminent unconsciousness, control of the aircraft can be removed from the pilot and the aircraft unloaded to reduce G-loading. The apparatus is made by removing the light emitting diode (LED) and light sensor from a commercially available pulse oximeter probe, or oxisensor, and cementing them on opposite sides of a conventional ear plug. The light emitted from the LED travels a reflective path through the vascular tissue surrounding the ear canal to be received by the light sensor on the other side of the canal.

Claims

1. An oximeter probe, comprising:

(a) a generally tubular plug made of pliable material and shaped to fit comfortably inside a living body cavity;

(b) light emitting means for emitting light of two or more preselected wavelengths, wherein the light emitting means is mounted and positioned inside the plug so that it can emit light outside the outer surface of the plug; and

,

(c) light sensing means for separately sensing the two or more preselected wavelengths of light emitted by the light emitting means, wherein the light sensing means is mounted and positioned inside the plug so that it can sense light impinging on the outer surface of the plug.

2. The oximeter probe according to claim 1, wherein the living body cavity is a human ear canal.

3. An oximeter probe comprising:

(a) a generally tubular plug made of pliable material and shaped to fit comfortably inside a living body cavity;

(b) light emitting means for emitting light of two or more preselected wavelengths, wherein the light emitting means is mounted and positioned inside the plug so that it can emit light outside the outer surface of the plug;

(c) light sensing means for sensing the light emitted by the light emitting means, wherein the light sensing means is mounted and positioned inside the lug so that it can sense light impinging on the outer surface of the plug; and

(d) wherein the light emitting means and light sensing means are positioned, respectively, to emit light in and to sense light from directions generally 180°

apart.

4. An oximeter probe comprising:

(a) a generally tubular plug made of pliable material and shaped to fit comfortably inside a living body cavity;

(b) light emitting means for emitting light of two or more preselected wavelengths, wherein the light emitting means is mounted and positioned inside the plug so that it can emit light outside the outer surface of the plug;

(c) light sensing means for sensing the light emitted by the light emitting means, wherein the light sensing means is mounted and positioned inside the plug so that it can sense light impinging on the outer surface of the plug; and

,

(d) wherein the light emitting means and light sensing means are mutually aligned along a line perpendicular to the central axis of the plug and face in opposite directions.

5. An oximeter probe, comprising:

(a) a generally tubular plug made of pliable material and shaped to fit comfortably inside a living ear canal;

(b) light emitting means for emitting light of two or more preselected wavelengths, wherein the light emitting means is mounted and positioned inside the plug so that it can emit light outside the outer surface of the plug; and

(c) light sensing means for separately sensing the two or more preselected wavelengths of light emitted by the light emitting means, wherein the light sensing means is mounted and positioned inside the plug so that it can sense light impinging on the outer surface of the plug.

6. An apparatus for protecting a pilot from harmful consequences of G-induced unconsciousness while piloting an aircraft, comprising:

(a) a generally tubular plug made of pliable material and shaped to fit comfortably inside a human ear canal;

(b) light emitting means for emitting light of two or more preselected wavelengths, wherein the light emitting means is mounted and positioned inside the plug so that it can emit light outside the outer surface of the plug;

(c) light sensing means for sensing the light emitted by the light emitting means, wherein the light sensing means is mounted and positioned inside the plug so that it can sense light impinging on the outer surface of the plug;

(c) means for calculating from the relative timing and intensity of the preselected light wavelengths the pulse rate and oxygen saturation levels of the blood flowing through blood vessels surrounding the ear canal; and

,

(d) means for unloading the aircraft to reduce the acceleration forces on the pilot whenever one or more of the pulse rate and the blood oxygen saturation level falls to a level indicating imminent unconsciousness of the pilot.

7. A method for measuring pulse rates and blood oxygen saturation levels, comprising the steps of:

(a) emitting a beam of light having a preselected plurality of wavelengths inside a living body cavity so that the light beam impinges on the inside surface of the body cavity;

(b) detecting the intensity of each of the preselected light wavelengths at a point on the inside surface of the body cavity generally opposite from where the light beam impinges; and

,

(c) calculating from the relative timing and intensity of the preselected light wavelengths the pulse rate and oxygen saturation levels of the blood flowing through blood vessels surrounding the body cavity.

8. The method for measuring pulse rates and blood oxygen saturation levels according to claim 7, wherein the living body cavity is a human ear canal.

9. A method for protecting a pilot from harmful consequences of G-induced unconsciousness while piloting an aircraft, comprising the steps of:

(a) measuring the pulse rate and blood oxygen saturation level of the pilot by a method comprising the steps of;

(i) emitting a beam of light having a preselected plurality of wavelengths inside an ear canal of the pilot so that the light beam impinges on the inside surface of the ear canal;

(ii) detecting the intensity of each of the preselected light wavelengths at a point on the inside surface of the ear canal generally opposite from where the light beam impinges; and

,

(iii) calculating from the relative timing and intensity of the preselected light wavelengths the pulse rate and oxygen saturation levels of the blood flowing through blood vessels surrounding the ear canal; and

,

(b) whenever one or more of the pulse rate and the blood oxygen saturation level falls to a level indicating imminent unconsciousness of the pilot, unloading the aircraft to reduce the acceleration and rate of change of acceleration on the pilot.

10. An oximeter probe, comprising:

(a) a generally tubular plug made of pliable material and shaped to resiliently fit inside a living body cavity;

(b) light emitting means for emitting light of two or more preselected wavelengths, wherein the light emitting means is mounted and positioned inside the plug so that it can emit light outside the outer surface of the plug; and

(c) light sensing means for separately sensing the two or more preselected wavelengths of light emitted by the light emitting means, wherein the light sensing means is mounted and positioned inside the plug so that it can sense light impinging on the outer surface of the plug.

11. An oximeter probe, comprising:

(a) a generally tubular plug made of pliable material and shaped to resiliently fit inside a living ear canal;

(b) light emitting means for emitting light of two or more preselected wavelengths, wherein the light emitting means is mounted and positioned inside the plug so that it can emit light outside the outer surface of the plug; and

,

(c) light sensing means for separately sensing the two or more preselected wavelengths of light emitted by the light emitting means, wherein the light sensing means is mounted and positioned inside the plug so that it can sense light impinging on the outer surface of the plug.