Evaluation of the Predictive Ability of Urinary NGAL as an Early Marker of Acute Kidney Injury Following Cardiac Surgery in Neonates and Infants

Urinary NGAL has been shown to be an early marker of AKI following paediatric cardiac surgery (2 hours off pump). Previous studies showed that an early increase of urinary NGAL following cardiopulmonary bypass was an excellent predictor for a later >50% increase in serum creatinine concentration in children undergoing cardiac surgery. Increased urinary concentrations of NGAL were found following open heart surgery. When defining AKI as an >50% increase of serum creatinine from baseline, the increase of urinary NGAL concentration two hours off pump appeared to be an excellent predictor of AKI. Several studies included heterogeneous populations of patients aged one month to 21 years undergoing cardiac surgery. Besides, NGAL concentrations have not been studied in neonates after open heart surgery, neither has been identified the threshold for accurate prediction of severe AKI requiring renal replacement therapy (RRT). If such a threshold was identified, urinary NGAL could be provided for intervention.

The aim of this observational cohort study is to describe postoperative kinetics of urinary NGAL in neonates and to identify the threshold for accurate prediction of severe AKI requiring RRT in neonates and infants undergoing cardiac surgery with cardiopulmonary bypass.

The study is entirely observational, the decision to initiate RRT continues to be based on clinical evidence of fluid overload, low cardiac output and oliguria. Urine samples are collected during the early postoperative period, stored, than NGAL concentrations are measures on the ARCHITECT platform.