Prediction of postoperative acute kidney injury after cardiopulmonary bypass cardiac surgery: The role of preoperative inflammatory indices and intraoperative perfusion stress

YILMAZ M. A., Guney M. Z., Uzun N., Kivanc H. E., sonmez e., AYDIN M. E.

Challenge Journal of Perioperative Medicine, cilt.4, sa.1, ss.21-31, 2026 (TRDizin)

Özet

Background: Postoperative acute kidney injury is a frequent complication after cardiac surgery performed with cardiopulmonary bypass and is closely associated with increased mortality. This study aimed to evaluate the predictive value of preoperative renal function, routinely available inflammatory indices, and intraoperative perfusion stress–related parameters for the development of postoperative acute kidney injury in adult cardiac surgery. Methods: This single-center retrospective cohort study included 455 adult patients aged 18 years or older who underwent elective or urgent coronary artery bypass grafting, valve surgery, or combined procedures with cardiopulmonary bypass between January 1, 2025 and January 1, 2026. Postoperative acute kidney injury was defined according to the Kidney Disease Improving Global Outcomes (KDIGO) criteria by comparing the highest serum creatinine value measured within the first 72 postoperative hours with the preoperative creatinine level obtained within 48 hours before surgery. Preoperative inflammatory indices derived from routine blood tests and intraoperative perfusion-related variables were recorded. Independent predictors of acute kidney injury were identified using parsimonious multivariable logistic regression analysis, and discriminative performance was assessed by receiver operating characteristic analysis. Results: Postoperative acute kidney injury occurred in 216 patients (47.5%), and 12.7% developed stage two or higher acute kidney injury. In-hospital mortality was significantly higher in patients with acute kidney injury compared with those without acute kidney injury (25.5% versus 6.7%), increasing progressively with advancing severity. Advanced age, higher preoperative serum creatinine, and longer cardiopulmonary bypass duration were independently associated with postoperative acute kidney injury. For stage two or higher acute kidney injury, age and cardiopulmonary bypass duration remained independent predictors. Although inflammatory indices were associated with acute kidney injury, they did not retain independent predictive value in adjusted models. Cardiopulmonary bypass duration demonstrated the strongest discriminative performance for KDIGO stage ≥2 acute kidney injury. Conclusions: Postoperative acute kidney injury is common after cardiac surgery with cardiopulmonary bypass and is strongly associated with increased in-hospital mortality. Age, baseline renal function, and cardiopulmonary bypass duration are key determinants of postoperative acute kidney injury, highlighting intraoperative perfusion stress as a clinically relevant and potentially modifiable risk factor.