System and method for determining stroke volume of a patient
AssigneeCovidien LP
InventorsPaul Stanley Addison, James Nicholas Watson
Life of this patent
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Abstract
A PPG system for determining a stroke volume of a patient includes a PPG sensor configured to be secured to an anatomical portion of the patient. The PPG sensor is configured to sense a physiological characteristic of the patient. The PPG system may include a monitor operatively connected to the PPG sensor. The monitor receives a PPG signal from the PPG sensor. The monitor includes a pulse trending module determining a slope transit time of an upslope of a primary peak of the PPG signal. The pulse trending module determines a stroke volume of the patient as a function of the slope transit time.
Claims20
A photoplethysmogram (PPG) system comprising:
- a PPG sensor configured to generate a PPG signal including a primary peak separated from a trailing peak by a dicrotic notch, the PPG sensor comprising:
- one or more light sources configured to emit light into a tissue of a patient;
- and
- one or more detectors configured to detect an amount of the light from the tissue, wherein the detected amount of the light corresponds to a physiological characteristic of the patient,
- wherein the PPG sensor comprises a non-invasive PPG sensor;
- and
- processing circuitry configured to:
- receive the PPG signal from the PPG sensor,
- determine a slope transit time of an upslope of the primary peak of the PPG signal, and
- determine a stroke volume of the patient based on the determined slope transit time.
A method comprising:
- receiving, by processing circuitry, a PPG signal from a PPG sensor, wherein the PPG sensor comprises a non-invasive PPG sensor;
- determining, by the processing circuitry, a slope transit time of an upslope of a primary peak of the PPG signal;
- determining, by the processing circuitry, a stroke volume of the patient based on the determined slope transit time;
- presenting, by the processing circuitry, the stroke volume on a display;
- determining, by the processing circuitry, that the determine stroke volume is greater than a threshold;
- and
- triggering, by the processing circuitry, an alarm in response to determining that the stroke volume is greater than the threshold.
A photoplethysmogram (PPG) system comprising:
- a non-invasive PPG sensor configured to generate a PPG signal including a primary peak separated from a trailing peak by a dicrotic notch, the PPG sensor comprising:
- one or more light sources configured to emit light into a tissue of a patient;
- and
- one or more detectors configured to detect the light emitted from the one or more light sources, wherein the detected light corresponds to a physiological characteristic of the patient;
- and
- processing circuitry configured to:
- receive the PPG signal from the PPG sensor,
- determine a contour of the PPG signal along an upslope of the primary peak,
- determine a slope transit time of the upslope of the primary peak of the PPG signal by at least:
- determining a gradient of the upslope for a given amplitude of the PPG signal, or
- determining a temporal gradient of the upslope, and
- determine a stroke volume of the patient based on the determined slope transit time, wherein the processing circuitry is configured to determine the stroke volume based on sensed PPG signals from only the non-invasive PPG sensor.
Dependencies are inferred from the claim text.