LCN2 and acute kidney injury: Several previous studies performed in patients undergoing cardiac surgery or liver transplantation suggest that NGAL levels at 0–6 h postsurgery are meaningful for the early detection of AKI [8–11, 13, 17], whereas a study performed in patients undergoing non-cardiac major surgery showed no correlation of NGAL levels at 2 or 6 h postsurgery with the development of AKI [18].