Patent ID: 9307928
Filing Date: 2016-04-12
CPC Classification: A61B,G16H

Claim Text:
1. A plethysmographic respiration detector responsive to respiratory effects appearing on a detected intensity waveform measured with an optical sensor at a blood perfused peripheral tissue site so as to provide a measurement of respiration rate, the plethysmographic respiration detector comprising: a preprocessor configured to identify a portion of a plethysmograph waveform which includes a physiologically acceptable series of plethysmograph waveform pulses; one or more processors configured to use a plurality of different techniques to derive a plurality of different frequency spectrums using the portion of the plethysmograph waveform, each of the plurality of different frequency spectrums responsive to at least one respiratory effect on the portion of the plethysmograph waveform and including a plurality of local maximums, the one or more processors comprising at least two of: a decision logic configured to determine a respiration rate based at least on a comparison of one or more local maximums of the first frequency spectrum and one or more local maximums of the second frequency spectrum, the decision logic comprising: wherein the decision logic is configured to generate a respiration rate output if the comparator finds at least one local maximum of each of the at least two of the baseline frequency spectrum, the AM frequency spectrum, and the SM frequency spectrum occur at matching frequencies within the first tolerance.