ObjectiveTo summarize the clinical experience and risk factors for acute kidney injury (AKI) in neonates undergoing congenital cardiac surgery and demonstrate whether neonatal AKI after cardiac surgery was independently related to perioperative short-term outcomes. MethodsMedical records of neonates undergoing congenital heart surgery from January 2014 to September 2021 were retrospectively reviewed. The patients were divided into an AKI group and a non-AKI group according to whether the AKI occured after the surgery. Multivariate logistic analysis was performed to analyze the risk factors for postoperative AKI and the relationship between postoperative AKI and postoperative short-term outcomes. ResultsA total of 609 patients were included. There were 395 males and 214 females with an age at surgery of 1.0-28.0 d and weight of 1.9-4.8 kg. After cardiac surgery, 139 neonates developed AKI. Multivariate logistic analysis showed that less intraoperative urine output [OR=0.96, 95%CI (0.94, 0.99), P=0.005], more intraoperative infusion of red blood cells [OR=1.49, 95%CI (1.16, 1.91), P=0.002], longer intraoperative deep hypothermic circulatory arrest time [OR=1.02, 95%CI (1.00, 1.04), P=0.020], higher vasoactive-inotropic score [OR=1.03, 95%CI (1.01, 1.04), P<0.001] and elevated lactate (increasing by 5 mmol/L) [OR=2.90, 95%CI (1.76, 4.76), P<0.001] when transferred to ICU were independent risk factors for AKI. AKI was an independent risk factor for increased in-hospital mortality [OR=12.61, 95%CI (3.00, 37.48), P<0.001]. ConclusionLess intraoperative urine output, more intraoperative infusion of red blood cells, longer intraoperative deep hypothermic circulatory arrest time, higher vasoactive-inotropic score and elevated lactate when transferred to ICU are independent risk factors for AKI. Furthermore, AKI is an independent risk factor for perioperative death after cardiac surgery.