Clemmesen CG, et al. - Elderly patients with a hip fracture were examined for the possible delay in perioperative anemia detection, accumulated perioperative anemia-associated burden, peripheral perfusion, and their association with patient outcomes. In this prospective study, researchers enrolled 51 patients and included 41 in the final analyses. They continuously monitored all patients for hemoglobin concentration (SpHb) and perfusion index (PI) with the Radical-7 Pulse CO-Oximeter and Rainbow R1 Adhesive Multi-parameter Sensors (Masimo Corp., Irvine, CA, US) from 12 h presurgery to 24 h postsurgery. This study showed a delay in transfusion threshold detection, and the presence of significant associations between low SpHb or time with low SpHb and postoperative outcomes. They observed mean delay in the detection of low Hb (< 10 g/dL) of 1.07 h using intermittent blood samples when compared with SpHb. These findings suggest that in the perioperative period, patients may spend hours with undetected/uncorrected anemia; there was an association of time spent in the anemic state with delirium.