Noninvasive and Continuous Hemoglobin Monitoring for Surgical Blood Management

This is a matched-pair cluster-randomized controlled trial. At each participating centers, consenting eligible Anesthesiologists will be grouped into matched pairs based on their practice characteristics and experience (namely, their main surgical service/procedures and their years of experience working as a clinician responsible for making transfusion decisions). From each pair, Anesthesiologists will be randomly allocated to either treat their patients while having access to data from a continuous noninvasive hemoglobin monitoring device (total hemoglobin \[SpHb\] and Pleth Variability Index \[PVI\]) (SpHb group) or without access to SpHb/PVI data, under standard of care (control group). Regardless of randomization, all patients will be monitored with the device but the data will be blinded and not be available to the Anesthesiologist to be used in the management of the control group. Only in the SpHb group, the SpHb/PVI data will be provided live to the Anesthesiologist, to be used during management of the patients.