Method for spectrophotometric blood oxygenation monitoring

• US 10,117,610 B2
• Filed: 10/03/2016
• Issued: 11/06/2018
• Est. Priority Date: 05/12/2005
• Status: Active Grant

• Current Assignee: Edwards Lifesciences Corporation
• Original Assignee: Cas Medical Systems Incorporated (Edwards Lifesciences Corporation)
• Inventors: Benni, Paul B.
• Primary Examiner(s): HINDENBURG, MAX F
• Application Number:
  US15/283,883
• Publication Number:
  US 20170086721A1
• Time in Patent Office: 764 Days
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/14552 Details of sensors specially adapted therefor
• CPC Class Codes: A61B 5/14553 specially adapted for cerebral tissue
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/6814 Head
• CPC Class Codes: G01N 2021/3144 for oxymetry
• CPC Class Codes: G01N 21/359 using near infrared light
• CPC Class Codes: G01N 21/49 within a body or fluid

Abstract

According to the present invention, a method and apparatus for non-invasively determining the blood oxygen saturation level within a subject'"'"'s tissue is provided. The method comprises the steps of: a) providing a spectrophotometric sensor operable to transmit light into the subject'"'"'s tissue, and to sense the light; b) detecting light after passage through the subject'"'"'s tissue using the sensor, and producing initial signal data from the light sensed; c) calibrating the sensor to that particular subject using the initial signal data, thereby accounting for the specific physical characteristics of the particular subject'"'"'s tissue being sensed; and d) using the calibrated sensor to determine the blood oxygen parameter value within the subject'"'"'s tissue.

Claims

1. A method for non-invasively determining a blood oxygen parameter value of a subject'"'"'s tissue, comprising:

providing a spectrophotometric sensor having one or more transducers and a processor portion, each transducer including at least one light source and at least one light detector, and the processor portion including at least one processor;

using the at least one processor to execute algorithmic instructions stored in a memory device, which instructions cause the at least one processor to;

control the at least one light source to transmit light at one or more wavelengths of red light into the subject'"'"'s tissue;

control the at least one light detector to sense the transmitted red light after passage through the subject'"'"'s tissue and produce initial signals representative of the sensed red light;

receive and process the initial signals from the at least one light detector and produce first signal data from the initial signals;

selectively alter the algorithmic instructions using the first signal data to account for the specific physical characteristics of the particular subject'"'"'s tissue being sensed; and

determine the blood oxygen parameter value within the subject'"'"'s tissue using the selectively altered algorithmic instructions.

2. The method of claim 1, wherein the one or more wavelengths of red light include light wavelengths in the range of about 622 nm to 780 nm.

3. The method of claim 2, wherein the one or more wavelengths of red light include visible light wavelengths in the range of about 622 nm to 700 nm.

4. The method of claim 3, wherein the one or more wavelengths of red light include light at the wavelength of about 690 nm.

5. The method of claim 1, wherein the blood oxygen parameter value within the subject'"'"'s tissue is determined using signals representative of light sensed by the at least one light detector subsequent to the sensing of the light used to produce the initial signals.

6. The method of claim 1, wherein the first signal data is attributable to non-pulsatile blood flow within the subject'"'"'s tissue.

7. The method of claim 1, wherein the blood oxygen parameter is oxyhemoglobin.

8. The method of claim 1, wherein the blood oxygen parameter is deoxyhemoglobin.

9. An apparatus for non-invasively determining a blood oxygen parameter value of a subject'"'"'s tissue, comprising:

at least one transducer having at least one light source and at least one light detector, wherein the transducer is configured to be applied to a tissue surface of the subject with the at least one light source positioned to transmit light into the subject'"'"'s tissue and the at least one light detector positioned to sense the transmitted light after passage through the subject'"'"'s tissue; and

a processor portion having at least one processor in communication with a memory device storing algorithmic instructions, which instructions cause the at least one processor to selectively;

control the at least one light source to transmit light at one or more wavelengths of red light into the subject'"'"'s tissue;

control the at least one light detector to sense the transmitted red light after passage through the subject'"'"'s tissue and produce initial signals representative of the sensed red light;

receive and process the initial signals from the at least one light detector and produce first signal data from the initial signals;

alter the algorithmic instructions using the first signal data to account for the specific physical characteristics of the particular subject'"'"'s tissue being sensed; and

determine the blood oxygen parameter value within the subject'"'"'s tissue using the selectively altered algorithmic instructions.

10. The apparatus of claim 9, wherein the one or more wavelengths of red light include light wavelengths in the range of about 622 nm to 780 nm.

11. The apparatus of claim 10, wherein the one or more wavelengths of red light include visible light wavelengths in the range of about 622 nm to 700 nm.

12. The apparatus of claim 11, wherein the one or more wavelengths of red light include light at the wavelength of about 690 nm.

13. The apparatus of claim 9, wherein the blood oxygen parameter value within the subject'"'"'s tissue is determined using signals representative of light sensed by the at least one light detector subsequent to the sensing of the light used to produce the initial signals.

14. The apparatus of claim 9, wherein the blood oxygen parameter is oxyhemoglobin.

15. The method of claim 9, wherein the blood oxygen parameter is deoxyhemoglobin.

16. The apparatus of claim 9, wherein the at least one light source is configured to transmit light along a plurality of wavelengths into the subject'"'"'s tissue.