Discrimination of cheyne-stokes breathing patterns by use of oximetry signals
First Claim
1. A computer implemented method of detecting an occurrence of Cheyne-Stokes respiration in one or more programmed processors comprising:
- accessing blood gas data representing a measured blood gas signal from an oximeter;
determining a duration of one or more contiguous periods of changing saturation of a blood gas from the blood gas data;
determining a presence of a peak in a predetermined frequency range for de-saturation and re-saturation cycles of the blood gas data;
detecting the occurrence of Cheyne-Stokes respiration from (a) a comparison of the determined duration and a threshold derived to differentiate saturation changes due to Cheyne-Stokes respiration and saturation changes due to obstructive sleep apnea, and (b) a comparison of the determined peak to a further threshold;
generating an output indicating the detected occurrence of Cheyne-Stokes respiration; and
determining a quality indicator for determining a confidence level associated with detecting the occurrence of Cheyne-Stokes respiration,wherein the processor determines the quality indicator by determining a number of samples where the measured blood gas signal drops below a predetermined percentage threshold.
2 Assignments
0 Petitions
Accused Products
Abstract
Methods and apparatus provide Cheyne-Stokes respiration (“CSR”) detection based on a blood gas measurements such as oximetry. In some embodiments, a duration, such as a mean duration of contiguous periods of changing saturation or re-saturation occurring in an epoch taken from a processed oximetry signal, is determined. An occurrence of CSR may be detected from a comparison of the duration and a threshold derived to differentiate saturation changes due to CSR respiration and saturation changes due to obstructive sleep apnea. The threshold may be a discriminant function derived as a classifier by an automated training method. The discriminant function may be further implemented to characterize the epoch for CSR based on a frequency analysis of the oximetry data. Distance from the discriminant function may be utilized to generate probability values for the CSR detection.
64 Citations
25 Claims
-
1. A computer implemented method of detecting an occurrence of Cheyne-Stokes respiration in one or more programmed processors comprising:
-
accessing blood gas data representing a measured blood gas signal from an oximeter; determining a duration of one or more contiguous periods of changing saturation of a blood gas from the blood gas data; determining a presence of a peak in a predetermined frequency range for de-saturation and re-saturation cycles of the blood gas data; detecting the occurrence of Cheyne-Stokes respiration from (a) a comparison of the determined duration and a threshold derived to differentiate saturation changes due to Cheyne-Stokes respiration and saturation changes due to obstructive sleep apnea, and (b) a comparison of the determined peak to a further threshold; generating an output indicating the detected occurrence of Cheyne-Stokes respiration; and determining a quality indicator for determining a confidence level associated with detecting the occurrence of Cheyne-Stokes respiration, wherein the processor determines the quality indicator by determining a number of samples where the measured blood gas signal drops below a predetermined percentage threshold. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A computer implemented method of detecting an occurrence of Cheyne-Stokes respiration in one or more programmed processors comprising:
-
accessing blood gas data representing a measured blood gas signal from an oximeter; determining a duration of one or more contiguous periods of changing saturation of a blood gas from the blood gas data; determining a presence of a peak in a predetermined frequency range for de-saturation and re-saturation cycles of the blood gas data; detecting the occurrence of Cheyne-Stokes respiration from (a) a comparison of the determined duration and a threshold derived to differentiate saturation changes due to Cheyne-Stokes respiration and saturation changes due to obstructive sleep apnea, and (b) a comparison of the determined peak to a further threshold; generating an output indicating the detected occurrence of Cheyne-Stokes respiration; and processing the blood gas data to remove artifact data, wherein the processing the blood gas data to remove artifact data comprises determining in the one or more programmed processors a beginning and end of a motion artifact period in the blood gas data by identifying with a derivative signal of the blood gas data an initial negative spike with a first lesser threshold followed by a positive spike with a second greater threshold. - View Dependent Claims (11, 12)
-
-
13. An apparatus to detect an occurrence of Cheyne-Stokes breathing, the apparatus comprising:
-
a memory for blood gas data representing a measured blood gas signal from an oximeter; and a processor coupled with the memory, the processor being configured (a) to determine a duration of one or more contiguous periods of changing saturation of a blood gas from the blood gas data;
(b) to determine a presence of a peak in a predetermined frequency range for de-saturation and re-saturation cycles of the blood gas data;
(c) to detect an occurrence of Cheyne-Stokes respiration from (1) a comparison of the determined duration and a threshold derived to differentiate saturation changes due to Cheyne-Stokes respiration and saturation changes due to obstructive sleep apnea, and (2) a comparison of the determined peak to a further threshold; and
(d) to generate an output indicating the detected occurrence of Cheyne-Stokes respiration,wherein the processor is further configured to determine a quality indicator for determining a confidence level associated with detecting the occurrence of Cheyne-Stokes respiration, and wherein the processor determines the quality indicator by determining a number of samples where the measured blood gas signal drops below a predetermined percentage threshold. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21)
-
-
22. An apparatus to detect an occurrence of Cheyne-Stokes breathing, the apparatus comprising:
-
a memory for blood gas data representing a measured blood gas signal from an oximeter, and a processor coupled with the memory, the processor being configured (a) to determine a duration of one or more contiguous periods of changing saturation of a blood gas from the blood gas data;
(b) to determine a presence of a peak in a predetermined frequency range for de-saturation and re-saturation cycles of the blood gas data;
(c) to detect an occurrence of Cheyne-Stokes respiration from (1) a comparison of the determined duration and a threshold derived to differentiate saturation changes due to Cheyne-Stokes respiration and saturation changes due to obstructive sleep apnea, and (2) a comparison of the determined peak to a further threshold; and
(d) to generate an output indicating the detected occurrence of Cheyne-Stokes respiration,wherein the processor is further configured to process the blood gas data to remove artifact data, and wherein the processor is configured to process the blood gas data to remove artifact by determining a beginning and end of a motion artifact period in the blood gas data by identifying with a derivative signal of the blood gas data an initial negative spike with a first lesser threshold followed by a positive spike with a second greater threshold. - View Dependent Claims (23, 24)
-
-
25. An apparatus for detecting an occurrence of Cheyne-Stokes respiration comprising:
-
means for accessing blood gas data representing a measured blood gas signal from an oximeter; means for determining a duration of one or more contiguous periods of changing saturation of a blood gas from the blood gas data; means for determining a presence of a peak in a predetermined frequency range for de-saturation and re-saturation cycles of the blood gas data; and means for detecting the occurrence of Cheyne-Stokes respiration from (a) a comparison of the determined duration and a threshold derived to differentiate saturation changes due to Cheyne-Stokes respiration and saturation changes due to obstructive sleep apnea, and (b) a comparison of the determined peak to a further threshold; and means for generating an output indicating the detected occurrence of Cheyne-Stokes respiration means for determining a quality indicator for determining a confidence level associated with detecting the occurrence of Cheyne-Stokes respiration, wherein the quality indicator is determined by determining a number of samples where the measured blood gas signal drops below a predetermined percentage threshold.
-
Specification