ALB and acute kidney injury: To address these constraints, future research should pursue (1) prospective multicenter validation across varied healthcare tiers to establish context-specific FAR thresholds; (2) longitudinal biomarker studies integrating single-cell sequencing to resolve spatiotemporal causality between FAR elevation and tubulopathy; and (3) wearable-AI hybrid models enabling continuous fibrinogen/albumin monitoring coupled with LSTM networks for ultra-early AKI warning (e.g., predicting imminent AKI within 6–12 h postoperatively).