System And Method For Estimating Blood Analyte Concentration

• US 20090247845A1
• Filed: 03/27/2009
• Published: 10/01/2009
• Est. Priority Date: 03/28/2008
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Nellcor Puritan Bennett LLC (Medtronic Plc)
• Inventors: Pav, Steven E.
• Granted Patent: US 8,437,822 B2
• Time in Patent Office: Days
• US Class Current: 600/322
• 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 5/6826 Finger
• CPC Class Codes: A61B 5/6838 Clamps or clips

Abstract

There is provided a system and method for estimating blood analyte concentration using a non-invasive medical device. The method includes detecting light from a plurality of light sources and generating signals representative of observed absorption of the light from the plurality of light sources. Blood analyte concentrations are then estimated using support vector regression analysis.

Claims

1. A system for estimating blood analyte concentration comprising:

a sensor comprising;

a plurality of light sources; and

a detector configured to generate signals based on light from the plurality of light sources; and

a monitor coupled to the sensor configured to;

receive the signals generated by the detector;

estimate blood analytes using support vector regression analysis; and

output the estimated blood analyte concentration.

2. The system of claim 1, wherein the plurality of light sources comprises three light sources operating at different wavelengths.

3. The system of claim 2, wherein the three light sources comprise:

a first light source operating in the red region of the electromagnetic spectrum; and

second and third light sources operating in the IR region of the electromagnetic spectrum.

4. The system of claim 1, wherein the monitor is configured to estimate the blood analyte concentration using an equation having the form

5. The system of claim 4, wherein the kernel k a nonlinear kernel.

6. A method for non-invasively estimating blood analyte concentration comprising:

detecting light from a plurality of light sources;

generating signals representative of observed absorption of the light from the plurality of light sources;

estimating blood analyte concentrations using support vector regression analysis.

7. The method of claim 6, wherein the estimating blood analyte concentrations comprises solving for an equation having a form:

8. The method of claim 6, wherein detecting light from a plurality of light sources comprises operating three light sources comprising a first light source operating in the red region of the electromagnetic spectrum, and second and third light sources operating in the infrared region of the electromagnetic spectrum.

9. The method of claim 7, wherein the kernel is a polynomial kernel.

10. The method of claim 7, wherein the kernel is a non-linear kernel.

11. The method of claim 7, wherein the kernel is a sigmoidal kernel.

12. The method of claim 7, wherein the kernel is a Gaussian kernel.

13. A method of manufacturing a non-invasive medical device comprising:

programming a non-invasive medical device to solve an support vector regression problem having a form;

14. The method of claim 13, wherein devising a pretransform comprises performing the transform g(x)=x/∥

x∥

₂.

15. The method of claim 13, wherein selecting the kernel comprises selection one of nonlinear kernels:

K(u,v)=(u·

v+c)^k, (Polynomial)

K(u,v)=tan h(cu·

v+Θ

), (Sigmoidal)

K(u,v)=e<sup>−

∥

u−

v∥

22/2σ

2</sup>, (Galissilan)

16. The method of claim 13, wherein gathering training data comprises converting saturation data from a second hand to equivalent rat-rat.

17. The method of claim 13, wherein the test result is sufficiently accurate if the computed y is within the ε

-tube for the support vector regression problem.