The objectives of this study were to evaluate the incidence and to identify risk factors for acute kidney injury (AKI) in neonates undergoing cardiopulmonary bypass (CPB) with a miniaturized bloodless primed extracorporeal circuit.

A retrospective cohort study.

A single-center, tertiary academic hospital.

Data of 462 patients were analyzed.

With a retrospective analysis of neonates undergoing CPB with bloodless priming between May 2007 and August 2019, the incidence of AKI was determined according to the neonatal Kidney Disease: Improving Global Outcomes classification. Multivariate logistic regression analyses were performed to determine risk factors for AKI.

The incidence of AKI was 41.1% (190 of 462); 30.3% (n = 140) had mild stage 1, 6.5% (n = 30) reached stage 2, and 4.3% (n = 20) reached stage 3. Multivariate logistic regression showed that degree of hypothermia (p = 0.05), duration of CPB (p = 0.03), and lower baseline serum creatinine (p < 0.001) were associated independently with AKI. In the authors’ patient population, patients without transfusion of donor-derived erythrocytes had a lower incidence of AKI (p = 0.003). AKI stages 2 and 3 were associated with longer duration of mechanical ventilation (p = 0.008) and increased length of stay in the intensive care unit (p = 0.03).

With a miniaturized CPB circuit and bloodless priming, the AKI incidence was well within the range consistent with previously reported studies from other institutions.