Abstract: A system for measuring a blood pressure value from a patient features a sensor configured to be worn on the patient's thumb. The sensor includes one or two light sources that emit optical radiation, and a photodetector that detects the optical radiation after it passes through a portion of a vessel (e.g. an artery or capillary) in the patient's thumb to generate a first time-dependent signal (e.g. a PPG waveform). In embodiments the sensor is made from a flexible material that wraps around a portion of the patient's thumb (e.g. the base) while leaving the thumb's tip uncovered. This configuration is less awkward than most finger-worn sensors, and allows the patient to comfortably go about their day-to-day activities (e.g. reading, eating) with little obstruction. The system also includes at least two electrodes that are configured to be worn on the patient's body and detect electrical signals that are processed by an electrical circuit to generate a second time-dependent signal (e.g. an ECG waveform).

Abstract: A sensor for monitoring a patient's blood pressure, the sensor including a housing unit with a back surface and which includes: a pair of electrodes mounted on the back surface; an optical system mounted on the back surface and including at least one light source that emits optical radiation near 570 nm and at least one photodetector; a first amplifier which generates an analog electrical waveform from the electrical signals from the electrodes; a second amplifier that generates an analog optical waveform from the optical signal from the photodetector; analog-to-digital converter circuitry configured to receive the analog electrical waveform and generate a digital electrical waveform therefrom and to receive the analog optical waveform and generate a digital optical waveform therefrom; and a processor programmed to receive the digital electrical and optical waveforms and determine a pulse transit time for the patient which is a measure of a separation in time of a first feature of the digital electrical wavef