PLETHYSMOGRAPH VARIABILITY PROCESSOR
First Claim
Patent Images
1. A plethysmograph variability method comprising:
- inputting a plethysmograph waveform having a plurality of pulses corresponding to pulsatile blood flow within a tissue site;
deriving a plurality of perfusion values corresponding to the pulses;
determining a plurality of variability values each indicative of the variability of a series of the perfusion values;
calculating a plethysmograph variability index representative of the variability values; and
displaying the plethysmograph variability index.
4 Assignments
0 Petitions
Accused Products
Abstract
A plethysmograph variability processor inputs a plethysmograph waveform having pulses corresponding to pulsatile blood flow within a tissue site. The processor derives plethysmograph values based upon selected plethysmograph features, determines variability values, and calculates a plethysmograph variability parameter. The variability values indicate the variability of the plethysmograph features. The plethysmograph variability parameter is representative of the variability values and provides a useful indication of various physiological conditions and the efficacy of treatment for those conditions.
-
Citations
30 Claims
-
1. A plethysmograph variability method comprising:
-
inputting a plethysmograph waveform having a plurality of pulses corresponding to pulsatile blood flow within a tissue site; deriving a plurality of perfusion values corresponding to the pulses; determining a plurality of variability values each indicative of the variability of a series of the perfusion values; calculating a plethysmograph variability index representative of the variability values; and displaying the plethysmograph variability index. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A plethysmograph variability processing system comprising:
-
an optical sensor that transmits multiple wavelengths of optical radiation into a tissue site, detects the optical radiation after attenuation by pulsatile blood flowing within the tissue site, and generates a sensor signal responsive to the detected optical radiation; a patient monitor that demodulates the sensor signal so as to generate a plurality of plethysmograph channels; a digital signal processor (DSP) within the patient monitor that inputs at least one of the plethysmograph channels and outputs a plethysmograph variability (PV) parameter accordingly; a PV process that executes on the DSP so as to process the at least one plethysmograph channel and derive the PV parameter; and a patient monitor output that is responsive to the PV parameter. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A plethysmograph variability method comprising:
-
inputting at least one of a plurality of plethysmograph channels measuring a plurality of plethysmograph values from the input; defining a plurality of windows each encompassing a unique time interval of the plethysmograph values; calculating a plurality of variability values, each of the variability values derived from the plethysmograph values encompassed in a unique one of the windows; defining a second plurality of windows each encompassing a unique time interval of the variability values; calculating a plurality of parameter values, each of the parameter values derived from the variability values encompassed in a unique one of the second windows; and outputting the parameter values. - View Dependent Claims (19, 20, 21, 22, 23, 24, 30)
-
-
25. A plethysmograph variability processing system having a sensor that transmits multiple wavelengths of optical radiation into a tissue site and that detects the optical radiation after attenuation by pulsatile blood flow within a tissue site so as to provide a plethysmograph input to a digital signal processor (DSP), the input selected from a plurality of channels corresponding to the multiple wavelengths, the DSP executes instructions for deriving plethysmograph variability from the plethysmograph, comprising:
-
a plethysmograph input; a measuring means for generating plethysmograph values from the plethysmograph input according to predefined plethysmograph features; a calculation means for deriving variability values from the plethysmograph values; and a reduction means for deriving a plethysmograph variability (PV) parameter from the plethysmograph values. - View Dependent Claims (26, 27, 28, 29)
-
Specification