Physiological sensor resembling a neck-worn collar

A sensor for measuring photoplethysmogram (PPG) and electrocardiogram (ECG) waveforms and blood oxygen (SpO2) values from a patient, the sensor comprising:

• a primary housing, wherein during use the primary housing is configured to rest entirely on a middle of the patient's chest, the primary housing comprising a first portion and a second portion, the first portion disposed above the second portion
• a secondary housing coupled to the primary housing via a flexible wire, the secondary housing including a heating element, a temperature sensor, and an optical system, wherein the secondary housing is disposed adjacent to a shoulder, and wherein;
• the heating element is attached to a bottom surface of the secondary housing so that it contacts and heats an area adjacent to the shoulder;
• the temperature sensor is in direct contact with the heating element;
• the optical system comprises a light source configured to generate optical radiation in both the red spectral region and infrared spectral region, a optical sensor oriented within the secondary housing so that the optical radiation irradiates the area of the patient's chest, and a photodetector configured to generate a red PPG waveform by detecting optical radiation in the red spectral region that reflects off the area after it is heated by the heating element, the photodetector further configured to generate an infrared PPG waveform by detecting optical radiation in the infrared spectral region that reflects off the area after it is heated by the heating element;
• wherein the secondary housing further includes two electrode leads, wherein one of the two electrode leads is disposed away from the optical system via an articulating arm,
• wherein the primary housing comprises an ECG sensor comprising two electrode leads and an ECG circuit, the ECG circuit configured to receive signals from the electrode leads when the sensor is worn by the patient and, after processing them, generate an ECG waveform;
• wherein the primary housing further comprises a processing system configured to analyze the ECG waveform to identify a first fiducial marker comprised in the ECG waveform, and based on the first fiducial marker, identify a first set of fiducial markers comprised in the red PPG waveform, and a second set of fiducial markers comprised in the infrared PPG waveform, the processing system further configured to collectively process the first and second set of fiducial markers to generate the SpO2 value;
• and,
• a closed-loop temperature controller comprised within the secondary housing and in electrical contact with each of the heating element, the temperature sensor, and the processing system, the closed-loop temperature controller configured to:
• 1) receive a first signal from the temperature sensor;
• 2) receive a second signal from the processing system corresponding to one of the first and second sets of fiducial markers;
• 3) collectively process the first and second signals to generate a control parameter;
• and 4) control an amount of heat generated by the heating element based on the control parameter.