Ex vivo calibration of a photoplethysmographic device

A method for in vitro calibration of a photoplethysmographic device comprising the steps of:

• a. providing a fluid circuit;
• b. incorporating a pump mechanism in the fluid circuit;
• c. providing an excised tissue that includes at least one artery and a venous return portion;
• d. configuring the pump mechanism to generate pulsatile output fluid flow through the fluid circuit;
• e. connecting the pulsatile output fluid flow to the at least one artery of the excised tissue to incorporate the excised tissue in the fluid circuit;
• f. providing a photoplethysmographic device including an emitter and a photodetector;
• g. positioning the emitter so that light output by the emitter is incident on the excised tissue;
• h. positioning the photodetector so that a portion of the light output by the emitter passes through the excised tissue and is incident on the photodetector;
• i. introducing blood into the fluid circuit to be input to the pump mechanism;
• j. incorporating a sample access port in the fluid circuit for sampling the blood in the fluid circuit and for running the sampled blood through a reference instrument to obtain reference measurements;
• k. energizing the pump mechanism to move the blood through the excised tissue;
• l. energizing the emitter to output light;
• m. pairing data from the photodetector and one or more reference measurements of the obtained reference measurements;
• and
• n. processing the paired data to calibrate the photoplethysmographic device.