PERFUSION INDEX SMOOTHER

• US 20150245794A1
• Filed: 03/16/2015
• Published: 09/03/2015
• Est. Priority Date: 10/12/2006
• Status: Active Grant

• Current Assignee: Masimo Corporation
• Original Assignee: Masimo Corporation
• Inventors: Al-Ali, Ammar
• Granted Patent: US 10,194,847 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 5/0295 using plethysmography, i.e. measuring the variations in the volume of a body part as modified by the circulation of blood therethrough, e.g. impedance plethysmography
• 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 5/7207 of noise induced by motion artifacts
• CPC Class Codes: A61B 5/7278 Artificial waveform generation or derivation, e.g. synthesising signals from measured signals A61B5/327 takes precedence
• 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

An embodiment of the present disclosure seeks to smooth a perfusion index measurement through use of a baseline perfusion index measurement and/or through the use of multiple PI calculations. The combination of the baseline perfusion index measurement reduces an error between a calculated measurement of PI and actual conditions.

Claims

1. A method of determining an indication of perfusion index in a patient monitor, the method comprising:

receiving pleth data;

calculating at least two indications of perfusion index using at least two different calculation techniques; and

determining a final indication of perfusion index based on the at least two indications of perfusion index.

2. The method of claim 1, wherein the final indication of perfusion index is determined by selecting the lowest indication of perfusion index.

3. The method of claim 1, wherein the final indication of perfusion index is determined by statistical analysis.

4. The method of claim 1, wherein the final indication of perfusion index is determined by averaging the at least two indications of perfusion index.

5. A method of determining an indication of perfusion index, the method comprising:

receiving pleth data; and

determining an indication of perfusion index by utilizing at least one of a first calculation technique and a second calculation technique to determine a resulting indication of perfusion index.

6. The method of claim 5, wherein determining the indication of perfusion index comprises utilizing the calculation technique that will result in the lowest perfusion index value.

7. An oximeter comprising:

an input capable of receiving intensity signal data responsive to intensity signals acquired from a detector capable of detecting light attenuated by body tissue,

a first calculation calculator configured to calculate a first indication of perfusion index using a first calculation technique;

a second calculator configured to calculate a second indication of perfusion index using a second calculation technique; and

a processor configured to utilize at least one of the first and second calculators to determine a resulting indication of perfusion index.

8. The method of claim 7, wherein the processor is configured to select the calculator which calculates the lowest indication of perfusion index.

9. The method of claim 7, wherein the processor utilizes both calculation techniques.

10. The method of claim 9, wherein the processor is further configured to select the lowest indication of perfusion index as the resulting indication of perfusion index.

11. A method of determining an indication of a physiological condition using data responsive to intensity signals acquired from a detector capable of detecting light attenuated by body tissue, the method comprising:

determining one or more indications of pulse information from data responsive to intensity signals acquired from a detector capable of detecting light attenuated by body tissue;

determining a first indication of amplitude data for a pulse based on the one or more indications of pulse information;

determining a second indication of amplitude data for a combination of pulses based on the one or more indications of pulse information;

determining a final indication of amplitude data based on the first and second indications; and

outputting the final indication as an indication of perfusion index.

12. The method of claim 11, wherein the amplitude data is used to determine an indication of perfusion.

13. The method of claim 11, wherein determining a final indication further comprises selecting the lowest indication of amplitude from the first and second indications of amplitude.

14. The method of claim 11, wherein determining a final indication further comprises averaging the first and second indications of amplitude.

15. The method of claim 11, wherein determining a final indication is based on a statistical analysis of the first and second indications of amplitude.

16. The method of claim 11, wherein the combination comprises an averaged combination of pulses.

17. The method of claim 11, wherein the combination comprises a maximum and minimum amplitude of a plurality of pulses.

18. The method of claim 11, wherein the combination comprises a statistical combination of pulses.