BACKGROUND: Reduced oxygen delivery (DO METHODS: MEDLINE, Embase, the Cochrane Library, and Web of Science were electronically searched to identify comparative studies from inception until July 2023 that reported the association between intraoperative DO RESULTS: Of the 2513 papers identified, 10 studies, including 21,875 participants, were included. Of these, three studies reported on delirium, two on POCD, and five on CVA. Eight studies reported reduced intraoperative DO CONCLUSIONS: Limited data suggest that maintaining intraoperative DO