Devices and methods for assessing pulmonary status using optical oxygenation sensing

A method for measuring an oxygenation status in a patient comprising:

• bringing an oxygenation monitoring device into contact with a tissue of the patient, the oxygenation monitoring device comprising an optical sensor comprising:
• an implantable housing defining an interior volume, the implantable housing comprising:
• control circuitry disposed within the interior volume a first optical emitter coupled to the implantable housing and in electrical communication with the control circuitry, wherein the first optical emitter is configured to emit light at a first wavelength from 100 nanometers (nm) to 2000 nm;
• a second optical emitter coupled to the implantable housing and in electrical communication with the control circuitry, wherein the second optical emitter is configured to emit light at a second wavelength that is different from the first wavelength;
• and
• a first optical detector coupled to the implantable housing and in electrical communication with the control circuitry, wherein the first optical detector is configured to detect incident light;
• wherein the first optical emitter is spaced a first distance away from the first optical detector along a planar surface of the device;
• wherein the second optical emitter is spaced a second distance away from the first optical detector along the planar surface of the device, wherein the first distance is greater than the second distance;
• implanting the oxygenation monitoring device subcutaneously at or near a site of a lung tissue so that the first light emitter and the first light detector are directed toward an interior of the patient toward a surface of the lung tissue;
• propagating a first emitted light from the first optical emitter at the first wavelength to a region of the lung tissue at a first depth;
• propagating a second emitted light from the second optical emitter at the second wavelength to a second region of the lung tissue at a second depth, wherein the first depth is greater than the second depth;
• wherein the emitted light from the first optical emitter propagates through the lung tissue simultaneously with the emitted light from the second optical emitter;
• detecting an incident light with the optical detector;
• determining an oxygenation status of the lung tissue based on the detected incident light;
• wherein determining the oxygenation status comprises performing a ratiometric calculation using a ratio of a first molar extinction coefficient at the first wavelength to a second molar extinction coefficient at the second wavelength.