Abstract: A physiological sensor has light emitting sources, each activated by addressing at least one row and at least one column of an electrical grid. The light emitting sources are capable of transmitting light of multiple wavelengths and a detector is responsive to the transmitted light after attenuation by body tissue.

Abstract: A patient monitor has multiple sensors adapted to attach to tissue sites of a living subject. The sensors generate sensor signals that are responsive to at least two wavelengths of optical radiation after attenuation by pulsatile blood within the tissue sites.

Abstract: A portable patient monitor has an integrated mode in which it operates as a plug-in module for a multiparameter patient monitoring system (MPMS). The patient monitor also has a portable mode in which it operates separately from the MPMS as a battery-powered handheld or standalone instrument. The patient monitor has a sensor port that receives a signal indicative of physiological parameters as input to an internal processor. The patient monitor processes this sensor signal to derive patient measurements. In the portable mode, this information is provided on its display. In the integrated mode, the patient monitor provides patient measurements to the MPMS to be displayed on a MPMS monitor.

Abstract: A method and an apparatus for separating a composite signal into a plurality of signals is described. A signal processor receives a composite signal and separates a composite signal into separate output signals. Feedback from one or more of the output signals is provided to a configuration module that configures the signal processor to improve a quality of the output signals. In one embodiment, calibration data from multiple calibration data sets is used to configure the demodulation of the composite signal into separate output signals.

Abstract: Embodiments of the present disclosure provide a hypersaturation index for measuring a patient's absorption of oxygen in the blood stream after a patient has reached 100% oxygen saturation. This hypersaturation index provides an indication of the partial pressure of oxygen of a patient. In an embodiment of the present invention, a hypersaturation index is calculated based on the absorption ratio of two different wavelengths of energy at a measuring site. In an embodiment of the invention, a maximum hypersaturation index threshold is determined such that an alarm is triggered when the hypersaturation index reaches or exceeds the threshold. In another embodiment, an alarm is triggered when the hypersaturation index reaches or falls below its starting point when it was first calculated.

Abstract: A method and an apparatus for separating a composite signal into a plurality of signals is described. A signal processor receives a composite signal and separates a composite signal into separate output signals. Feedback from one or more of the output signals is provided to a configuration module that configures the signal processor to improve a quality of the output signals. In one embodiment, calibration data from multiple calibration data sets is used to configure the demodulation of the composite signal into separate output signals.

Abstract: A physiological parameter tracking system has a reference parameter calculator configured to provide a reference parameter responsive to a physiological signal input. A physiological measurement output is a physiological parameter derived from the physiological signal input during a favorable condition and an estimate of the physiological parameter according to the reference parameter during an unfavorable condition.

Abstract: Embodiments of the present disclosure provide a hypersaturation index for measuring a patient's absorption of oxygen in the blood stream after a patient has reached 100% oxygen saturation. This hypersaturation index provides an indication of the partial pressure of oxygen of a patient. In an embodiment of the present invention, a hypersaturation index is calculated based on the absorption ratio of two different wavelengths of energy at a measuring site. In an embodiment of the invention, a maximum hypersaturation index threshold is determined such that an alarm is triggered when the hypersaturation index reaches or exceeds the threshold. In another embodiment, an alarm is triggered when the hypersaturation index reaches or falls below its starting point when it was first calculated.

Abstract: A processor provides signal quality based limits to a signal strength operating region of a pulse oximeter. These limits are superimposed on the typical gain dependent signal strength limits. If a sensor signal appears physiologically generated, the pulse oximeter is allowed to operate with minimal signal strength, maximizing low perfusion performance. If a sensor signal is potentially due to a signal induced by a dislodged sensor, signal strength requirements are raised. Thus, signal quality limitations enhance probe off detection without significantly impacting low perfusion performance. One signal quality measure used is pulse rate density, which defines the percentage of time physiologically acceptable pulses are occurring. If the detected signal contains a significant percentage of unacceptable pulses, the minimum required signal strength is raised proportionately.

Abstract: A patient monitor has multiple sensors adapted to attach to tissue sites of a living subject. The sensors generate sensor signals that are responsive to at least two wavelengths of optical radiation after attenuation by pulsatile blood within the tissue sites.

Abstract: A time domain rule-based processor provides recognition of pulses in a pulse oximeter-derived waveform.

Abstract: The disclosure includes pulse oximetry systems and methods for determining point-by-point saturation values by encoding photoplethysmographs in the complex domain and processing the complex signals. The systems filter motion artifacts and other noise using a variety of techniques, including statistical analysis such as correlation, or phase filtering.

Abstract: A patient interface in accordance with one embodiment of the present disclosure is configured to be at least partially carried by a patient and to receive gas exhaled by the patient. The patient interface includes first and second cannula tubes each having a first end and a second end, the first ends are configured to be inserted into the nostrils of a patient, the first and second cannula tubes are configured to direct exhaled gas from the patient from the first ends to said second ends. The patient interface also includes first and second sensors positioned near the second ends, and the first and second sensors are configured to provide first and second signals based upon the gas, wherein the first and second signals are indicative of a physiological parameter of the patient. The patient interface also includes a communications link configured to provide the signal to a physiological monitor.

Abstract: Confidence in a physiological parameter is measured from physiological data responsive to the intensity of multiple wavelengths of optical radiation after tissue attenuation. The physiological parameter is estimated based upon the physiological data. Reference data clusters are stored according to known values of the physiological parameter. At least one of the data clusters is selected according to the estimated physiological parameter. The confidence measure is determined from a comparison of the selected data clusters and the physiological data.

Abstract: A method and an apparatus to analyze two measured signals that are modeled as containing desired and undesired portions such as noise, FM and AM modulation. Coefficients relate the two signals according to a model defined in accordance with the present invention. In one embodiment, a transformation is used to evaluate a ratio of the two measured signals in order to find appropriate coefficients. The measured signals are then fed into a signal scrubber which uses the coefficients to remove the unwanted portions. The signal scrubbing is performed in either the time domain or in the frequency domain. The method and apparatus are particularly advantageous to blood oximetry and pulserate measurements. In another embodiment, an estimate of the pulserate is obtained by applying a set of rules to a spectral transform of the scrubbed signal. In another embodiment, an estimate of the pulserate is obtained by transforming the scrubbed signal from a first spectral domain into a second spectral domain.

Abstract: A patient monitor has multiple sensors adapted to attach to tissue sites of a living subject. The sensors generate sensor signals that are responsive to at least two wavelengths of optical radiation after attenuation by pulsatile blood within the tissue sites.

Abstract: A method and an apparatus measure blood oxygenation in a subject. A light source is activated to cause a first emission at a first wavelength and a second emission at a second wavelength. A detector detects a composite signal indicative of an attenuation of the first and second wavelengths by tissue of a patient. The composite signal is demodulated into a first intensity signal and a second intensity signal. Blood oxygenation in the subject is determined from the first and second intensity signals.

Abstract: The present disclosure includes a portable physiological monitor including a first local display and configured to communicate with a second physiological monitor including a second display.

Abstract: A method and an apparatus measure blood oxygenation in a subject. A light source is activated to cause a first emission at a first wavelength and a second emission at a second wavelength. A detector detects a composite signal indicative of an attenuation of the first and second wavelengths by tissue of a patient. The composite signal is demodulated into a first intensity signal and a second intensity signal. Blood oxygenation in the subject is determined from the first and second intensity signals.

Abstract: A method and an apparatus to analyze two measured signals that are modeled as containing desired and undesired portions such as noise, FM and AM modulation. Coefficients relate the two signals according to a model defined in accordance with the present invention. In one embodiment, a transformation is used to evaluate a ratio of the two measured signals in order to find appropriate coefficients. The measured signals are then fed into a signal scrubber which uses the coefficients to remove the unwanted portions. The signal scrubbing is performed in either the time domain or in the frequency domain. The method and apparatus are particularly advantageous to blood oximetry and pulserate measurements. In another embodiment, an estimate of the pulserate is obtained by applying a set of rules to a spectral transform of the scrubbed signal. In another embodiment, an estimate of the pulserate is obtained by transforming the scrubbed signal from a first spectral domain into a second spectral domain.