Abstract: A physiological monitoring system may receive a sensor signal from a physiological sensor. The system may determine a parameter based on the sensor signal, for example variability of a blood oxygen saturation value or the percent modulation of a light signal. The system may determine a light drive parameter limit based on one or more parameters. For example, the system may determine a light drive current limit. The frequency of changes in the limit may be regulated using a state machine and other techniques that include hysteresis. An extant light drive parameter may be updated or changed in accordance with the light drive parameter limit and a light drive signal may be generated based on the light drive parameter.

Abstract: Provided herein are methods and apparatuses for facilitating clinical acceptance of patient monitoring features. These methods may be used in conjunction with a computer that includes software for viewing the type of display associated with the monitoring feature. The clinical acceptance systems as provided herein may display a new or experimental monitoring feature along with a benchmark feature that a clinician is familiar with. In certain embodiments, the viewing tool may be isolated from the calculation tools so that the computer may include stored files that are in a format ready for display.

Abstract: Provided herein are methods and apparatuses for facilitating clinical acceptance of patient monitoring features. These methods may be used in conjunction with a computer that includes software for viewing the type of display associated with the monitoring feature. The clinical acceptance systems as provided herein may display a new or experimental monitoring feature along with a benchmark feature that a clinician is familiar with. In certain embodiments, the viewing tool may be isolated from the calculation tools so that the computer may include stored files that are in a format ready for display.

Abstract: Systems and methods for processing photoplethysmograph (PPG) signals to determine a differential pulse transit time (DPTT) are disclosed. Sensors may be used to obtain first and second PPG signals from a subject. The sensors may be placed at different locations on the subject's body. A first algorithm may be performed on the PPG signals or on signals derived from them to obtain a DPTT. A corresponding confidence measure may be determined and if the confidence measure falls within a first numerical range, the calculated DPTT may be used. On the other hand, if the confidence measure falls within a second numerical range, an alternative algorithm may be performed on the PPG signals or on signals derived from them and the DPTT obtained using the alternative algorithm may be used. The DPTT may be used to perform continuous or periodic measurements of blood pressure.