Sine saturation transform

• US 9,814,418 B2
• Filed: 11/17/2014
• Issued: 11/14/2017
• Est. Priority Date: 06/29/2001
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Masimo Corporation
• Inventors: Weber, Walter M., Al-Ali, Ammar, Cazzoli, Lorenzo
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US14/543,325
• Publication Number:
  US 20150141781A1
• Time in Patent Office: 1,093 Days
• CPC Class Codes: A61B 5/024 Detecting, measuring or recording pulse rate or heart rate A61B5/0205, A61B5/021 take precedence
• CPC Class Codes: A61B 5/02433 for infrared radiation
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• 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 5/7282 Event detection, e.g. detecting unique waveforms indicative of a medical condition A61B5/4094, A61B5/4818, A61B5/349, A61B5/0823 take precedence

Abstract

A transform for determining a physiological measurement is disclosed. The transform determines a basis function index from a physiological signal obtained through a physiological sensor. A basis function waveform is generated based on basis function index. The basis function waveform is then used to determine an optimized basis function waveform. The optimized basis function waveform is used to calculate a physiological measurement.

Claims

1. A pulse oximeter system comprising:

an input configured to accept from a noninvasive optical sensor signals indicative of light attenuated by body tissue of a monitored patient; and

a hardware processor, responsive to said signals, operatively communicating with said input and configured to electronically;

determine a basis function index based, at least in part, on said one or more signals;

generate at least one basis function waveform based, at least in part, on said basis function index;

determine at least one optimized basis function waveform based, at least in part, on said at least one basis function waveform;

determine signal components based, at least in part, on said one or more signals and said at least one optimized basis function waveform; and

generate a physiological measurement responsive to said signal components;

a display configured to provide visual indicia of said physiological measurement.

2. The system of claim 1, wherein said generate at least one basis function waveform includes generate one or more sinusoidal waves.

3. The system of claim 1, wherein said determine at least one basis function index includes determine a frequency corresponding to said at least one basis function index.

4. The system of claim 1, wherein said signal components comprise frequency components based, at least in part, on said one or more signals and said at least one basis function waveform.

5. The system of claim 1, wherein said at least one basis function index corresponds to a pulse rate.

6. The system of claim 1, wherein said one or more signals comprises an IR signal and a RD signal.

7. The system of claim 6, wherein said hardware processor is configured to determine signal components responsive to said IR signal and said RD signal.

8. The system of claim 1, wherein said at least one basis function index corresponds to a pulse rate.

9. A method of determining a physiological parameter of a monitored patient attached to a noninvasive optical sensor, the method comprising:

receiving one or more signals indicative of light attenuated by body tissue of said monitored patient, said one or more signals usable to determine measurements for a physiological parameter of said monitored patient;

electronically determining at least one basis function index based, at least in part, on said one or more signals;

electronically generating at least one basis function waveform based, at least in part, on said at least one basis function index;

electronically determining at least one optimized basis function waveform based, at least in part, on said at least one basis function waveform;

electronically determining signal components of said one or more signals based, at least in part, on said at least one optimized basis function waveform and said one or more signals; and

electronically processing said signal components of said one or more signals to determine an output measurement of said physiological parameter.

10. The method of claim 9, wherein said generating at least one basis function waveform comprises generating one or more sinusoidal waves.

11. The method of claim 9, wherein said determining at least one basis function index includes determining a frequency corresponding to said at least one basis function index.

12. The method of claim 9, wherein said at least one basis function index corresponds to a pulse rate.

13. The method of claim 9, wherein said one or more physiological parameters comprises oxygen saturation.

14. The method of claim 9, further comprising outputting said physiological measurement to a display device.

15. The method of claim 9, wherein said electronically determining signal components of said one or more signals comprises determining frequency components of said one or more signals based, at least in part, on said at least one basis function waveform and said one or more signals.

16. A pulse oximeter system capable of determining a physiological parameter of a monitored patient attached to a noninvasive optical sensor, the pulse oximeter comprising:

means for receiving one or more signals indicative of light attenuated by body tissue of a monitored patient;

means for communicating with said input and determining a basis function index based, at least in part, on said one or more signals;

means for generating at least one basis function waveform based, at least in part, on said basis function index;

means for determining at least one optimized basis function waveform based, at least in part, on said at least one basis function waveform;

means for determining signal components based, at least in part, on said one or more signals and said at least one optimized basis function waveform; and

means for generating a physiological measurement responsive to said signal components.