Method for the presentation of information concerning variations of the perfusion

• US 20060167362A1
• Filed: 10/02/2003
• Published: 07/27/2006
• Est. Priority Date: 10/15/2002
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Bindszus, Andreas, Neumann, Rolf
• Granted Patent: US 7,572,230 B2
• Time in Patent Office: Days
• US Class Current: 600/504
• CPC Class Codes: A61B 5/0261 using optical means, e.g. infrared light
• 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
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence

Abstract

The invention relates to a method for the presentation of information concerning variations of the arterial filling with blood (perfusion) of organs of living beings on the user surface (10) of a display screen, in which method the data required for the presentation (perfusion index) is derived, using an algorithm, from measuring values of a non-invasive photometric measuring process for determining the arterial oxygen saturation of the blood. The invention is characterized in that a first perfusion index is defined as a reference value and the subsequent perfusion indices are determined as relative deviations with respect to the reference value, said relative deviations being presented in the form of analog, graphic elements (42, 44) on the user surface (10) as information concerning the 10 variations of the perfusion.

Claims

1. A method for the presentation of information concerning variations of the arterial filling with blood of organs of living beings on the user surface of a display unit, in which method the data required for the presentation is determined, using an algorithm, from measuring values produced by a non-invasive photometric measuring process for determining the arterial oxygen saturation of the blood, wherein a first perfusion index is defined as a reference value and the subsequent perfusion indices are determined as relative deviations with respect to the reference value, said relative deviations being presented as information concerning the variations of the perfusion on the user surface.

2. A method as claimed in claim 1, wherein the determination of the reference value takes place automatically at the beginning of the photometric measuring process.

3. A method as claimed in claim 1, wherein the instant of determination of the reference value can be chosen at will.

4. A method as claimed in claim 1, wherein the reference value is stored on a memory chip.

5. A method as claimed in claim 1, wherein the reference value as well as the subsequent perfusion indices are scaled by a factor.

6. A method as claimed in claim 5, wherein the factor is adjustable.

7. A method as claimed in claim 1, wherein the variation of the perfusion is presented in numerical form.

8. A method as claimed in claim 1, wherein analog graphic elements are used for the presentation.

9. A method as claimed in claim 8, wherein bar elements are used as the graphic elements.

10. A method as claimed in claim 9, wherein the relative variations of the perfusion are represented by different bar lengths.

11. A method as claimed in claim 8, wherein a representation in conformity with a tachometer display is used as the graphic element.

12. A method as claimed in claim 8, wherein the display is formed as a multidimensional type in conjunction with other physiological variables, notably as a spider diagram.

13. A method as claimed in claim 1, wherein an upper alarm limit and a lower alarm limit are provided.

14. A method as claimed in claim 13, wherein the alarm limit is adjustable.

15. A method as claimed in claim 13, wherein an acoustic and/or optical alarm signal is triggered when the alarm limit is exceeded.

16. (canceled)

17. A method of determining the quality of the measuring values derived by means of a photometric measuring process, wherein the signal quality is determined by the modulation factor (AC/DC) of one or more wavelengths in combination with one or more of the following variables:

saturation-independent perfusion index

transmission factor

extent of ambient disturbances, such as stray light, EM radiation, and the like

shape of the PLETH signal

strength and/or duration of artifacts.

18. A method of presenting the quality of the measuring values (signal quality) derived by means of the photometric measuring process, notably as claimed in claim 17, wherein this information is graphically presented on the user surface by way of different coloring of icons and/or background areas, the coloring depending on said quality.

19. A method as claimed in claim 18, wherein the icons are identical to the graphic elements used for the presentation of the perfusion.

20. A method as claimed in claim 18, wherein the icons are independent graphic elements.

21. A device, comprising a pulsoximeter for determining arterial O₂ saturation and for calculating perfusion index in order to determine information concerning variation of the perfusion, means for detection of interference signals, and for estimating the quality of the measuring values acquired and the information concerning a variation of the perfusion, and

means for presenting the information.