Postoperative anaemia: Hiding in plain sight.

Postoperative anaemia is common among surgical patients. While often viewed as a benign condition, postoperative anaemia is neither inevitable nor harmless, being intricately linked with adverse outcomes. In this review, we summarize the prevalence, aetiology, and outcomes of postoperative anaemia and highlight prevention and management strategies. Further, we propose a novel framework to characterize postoperative anaemia as an acute organ injury (i.e., acute blood injury, anaemic subtype), thereby drawing attention to a condition that is frequently overlooked. Additionally, we discuss areas warranting further research, including risk stratification for patients at heightened risk for the development of postoperative anaemia and associated complications and determination of appropriate treatment strategies.