Capacitance enhanced physiological measurements

Systems, methods, apparatuses, and software for measuring and determining physiological parameters of a patient are presented. In one example, a physiological measurement system includes an optical system configured to emit one or more optical signals into tissue of a patient, and detect the one or more optical signals after propagation through the tissue. The physiological measurement system includes a capacitance system configured to apply one or more electric field signals to a single side of the tissue to determine a capacitance signal based at least on changes in the one or more electric field signals, and a processing system configured to process at least the one or more detected optical signals and the capacitance signal to determine a physiological parameter of the patient.