A wearable physiological sensing device with optical pathways is described. The wearable physiological sensing device may include at least one light source a first light pipe coupled with the at least one light source, the first light pipe at least partially circumscribing an extremity of a patient, and including at least one aperture for radiating light from the light source into the extremity. The wearable physiological sensing device may also include a second light pipe including at least one aperture for receiving the light radiated through the extremity, the second light pipe at least partially circumscribing the extremity of the patient, and an optical receiver coupled with the second light pipe configured to receive the light and output one or more signals representative of the received light.
