According to the study design, CI-AKI was defined according to the KDIGO criteria (creatinine >0.3 mg/dL or >50% compared to baseline levels), and subclinical CI-AKI is defined as a positive result for the relevant biomarker (TIMP-2 и IGFBP7 > 0.3 (ng/mL)2/1000; NGAL > 90 μg/L). Here, LCN2 is linked to acute kidney injury.