METHODS AND SYSTEMS FOR POWER OPTIMIZATION IN A MEDICAL DEVICE

• US 20130324856A1
• Filed: 05/31/2012
• Published: 12/05/2013
• Est. Priority Date: 05/31/2012
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Nellcor Puritan Bennett LLC (Medtronic Plc)
• Inventors: Lisogurski, Daniel, Baker, Clark R. Jr.
• Granted Patent: US 9,241,676 B2
• Time in Patent Office: Days
• US Class Current: 600/476
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/02416 using photoplethysmograph signals, e.g. generated by infrared radiation A61B5/14552 takes precedence
• CPC Class Codes: A61B 5/02433 for infrared radiation
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/7285 for synchronising or triggering a physiological measurement or image acquisition with a physiological event or waveform, e.g. an ECG signal A61B6/5205, A61B6/541, A61B8/5207, A61B8/543 take precedence
• CPC Class Codes: A61B 5/746 Alarms related to a physiological condition, e.g. details of setting alarm thresholds or avoiding false alarms alarms per se G08B

Abstract

A physiological monitoring system may use photonic signals to determine physiological parameters. The system may vary parameters of a light drive signal used to generate the photonic signal from a light source such that power consumption is reduced or optimized. Parameters may include light intensity, firing rate, duty cycle, other suitable parameters, or any combination thereof. In some embodiments, the system may use information from a first light source to generate a light drive signal for a second light source. In some embodiments, the system may vary parameters in a way substantially synchronous with physiological pulses, for example, cardiac pulses. In some embodiments, the system may vary parameters in response to an external trigger.

Claims

1. A method of operating a physiological monitor, the method comprising:

receiving an external trigger, wherein the external trigger is based on a signal other than a light signal received by the physiological monitor; and

generating a light drive signal for activating a light source to emit a photonic signal, wherein at least one parameter of the light drive signal is configured to vary based on the external trigger.

2. The method of claim 1, wherein the external trigger is based on a signal received from an ECG sensor.

3. The method of claim 2, wherein the external trigger is based on an R-wave from the signal received from the ECG sensor.

4. The method of claim 1, wherein the external trigger is based on a signal received from a blood pressure sensor.

5. The method of claim 1, wherein the external trigger is based on a signal received from a respiratory sensor.

6. The method of claim 1, wherein the at least one parameter of the light drive signal comprises light intensity.

7. The method of claim 1, wherein the at least one parameter of the light drive signal comprises light source firing rate.

8. The method of claim 1, further comprising:

receiving a light signal attenuated by a subject; and

sampling the light signal at a sampling rate, wherein the sampling rate varies substantially synchronously with the variation of the at least one parameter of the light drive signal.

9. The method of claim 1, wherein the at least one parameter of the light drive signal comprises duty cycle.

10. The method of claim 1, further comprising:

receiving a light signal attenuated by a subject, wherein the light signal comprises a component corresponding to the photonic signal; and

determining a physiological parameter of the subject based on the component of the light signal.

11. The method of claim 1, wherein the at least one parameter of the light drive signal is further configured to vary based on one or more physiological parameters.

12. A physiological monitoring system, comprising processing equipment configured:

receive an external trigger, wherein the external trigger is based on a signal other than a light signal received by the physiological monitor; and

generate a light drive signal for activating a light source to emit a photonic signal, wherein at least one parameter of the light drive signal is configured to vary based on the external trigger.

13. The system of claim 12, wherein the external trigger is based on a signal received from an ECG sensor.

14. The system of claim 13, wherein the external trigger is based on an R-wave from the signal received from the ECG sensor.

15. The system of claim 12, wherein the external trigger is based on a signal from a blood pressure sensor.

16. The system of claim 12, wherein the external trigger is based on a signal received from a respiratory sensor.

17. The system of claim 12, wherein the at least one parameter of the light drive signal comprises light intensity.

18. The system of claim 12, wherein the at least one parameter of the light drive signal comprises light source firing rate.

19. The system of claim 12, further comprising:

receiving a light signal attenuated by a subject; and

sampling the light signal at a sampling rate, wherein the sampling rate varies substantially synchronously with the variation of the at least one parameter of the light drive signal.

20. The system of claim 12, wherein the at least one parameter of the light drive signal comprises duty cycle.

21. The system of claim 12, further comprising:

receiving a light signal attenuated by a subject, wherein the light signal comprises a component corresponding to the photonic signal; and

determining a physiological parameter of the subject based on the component of the light signal.

22. The system of claim 12, wherein the at least one parameter of the light drive signal is further configured to vary based on one or more physiological parameters.