Discussion
AKI, BPD, diuretic-induced
SECONDARY, PREMATURE
In this secondary analysis of a large, prospective, multicenter, randomized clinical trial of ELGANS, we evaluated the impact of fluid correction of serum creatinine on AKI diagnosis and its association with short-term and long-term outcomes. We found that fluid correction identified many neonates with previously undiagnosed AKI, and that correcting for fluid balance changed AKI staging in many patients. Fluid-corrected AKI correlated better with clinically relevant outcomes and was associated with increased odds of short-term clinical outcomes, including mechanical ventilation and grade 3 BPD. Furthermore, correcting serum creatinine for fluid balance created a new serum creatinine curve for neonates over the first 2 weeks of life, with a slow improvement in kidney function over time, which challenges the often cited peak and then fall serum creatinine trajectory over the first several postnatal days.Over the past several decades, the study of AKI has been most impacted by consensus definitions for diagnosis and staging.Our findings should be interpreted in the context of the unique physiology of the premature neonate. Premature neonates differ from older children in that they are subject to the full spectrum of fluid balance during the first 2 postnatal weeks including positive fluid balance, physiologic diuresis, and diuretic-induced diuresis, which impacts the diagnosis of AKI in neonates, because changes in fluid balance complicate the AKI diagnosis when using serum creatinine diagnostic criteria.