Higher preoperative albumin-corrected anion gap (ACAG) values significantly increased delirium risk by 56% and one-year mortality by 35% in 4,482 cardiac surgery patients. This blood chemistry marker, which adjusts standard anion gap measurements for albumin levels, outperformed traditional anion gap metrics in predicting both postoperative delirium (9.5% incidence) and death within one year (4.8% incidence). The finding represents a potentially valuable advance in cardiac surgery risk assessment. ACAG appears to capture the combined effects of inflammation, metabolic disturbances, and acid-base imbalances that predispose patients to neurological complications. Unlike expensive imaging or specialized tests, anion gap and albumin are routinely measured in standard blood panels, making this a cost-effective screening tool. The research addresses a critical need, as postoperative delirium affects cognitive recovery and increases healthcare costs. However, this retrospective analysis from a single healthcare system requires validation across diverse populations. As a preprint awaiting peer review, these results need independent confirmation before clinical implementation. The study's strength lies in its large cohort size and robust statistical modeling, though causation cannot be established from observational data.