Evaluation of neonatal acute kidney injury after critical congenital heart disease surgery

Background Acute kidney injury (AKI) is a common complication of congenital heart diseases (CHDs) after cardiac surgery. This study aimed to define the frequency and critical course, risk factors and short-term outcomes of AKI in postoperative CHD neonates. Methods Postoperatively followed term CHD newborn infants were enrolled in the study. Infants with congenital anomalies of the urinary tract and other major congenital anomalies were excluded. Neonatal modified KDIGO criteria were used to assess AKI. Results A total of 199 postoperatively followed newborn infants were included in the study. Acute kidney injury was detected in 71 (35.6%) patients. Of these patients, 24 (33.8%) were in stage 1, 14 (19.7%) in stage 2, and 33 (46.5%) in stage 3. Acute kidney injury occurred within the first week (median 1 day [IQR 1-2 d ays]) of cardiac surgery in 93% of the patients. The duration of invasive respiratory support and extracorporeal membrane oxygenation (ECMO) and mortality were significantly higher in stage 3 patients. Higher vasoactive-inotropic score (OR, 1.02; 95% CI, 1.0-1.04; p = 0.008) and receiving ECMO (OR, 7.9; 95% CI, 2.6-24.4; p = 0.001) were associated with risk for the development of AKI. The mortality rate was 52.1% in the AKI (+) patients, and having AKI (OR 7.1; 95% CI, 3.5-14.18) was significantly associated with mortality. Conclusion Acute kidney injury, a common early complication after critical neonatal CHD cardiac surgery, is associated with increased morbidity and mortality. Stage 3 AKI is associated with significantly higher mortality rates.