Assessment of Worldwide Acute Kidney Injury Epidemiology in Neonates 2.0

There is a growing focus on short- and long-term kidney health in neonates, including those with acute kidney injury (AKI). AKI occurs commonly in the Neonatal Intensive Care Unit (NICU) and is associated with adverse outcomes. In addition to poor outcomes during the hospitalization, infants discharged from the NICU may have an increased burden of kidney disease during childhood. Studies of long-term kidney function in children born prematurely show a fourfold increase in chronic kidney disease (CKD) by adolescence and into adulthood. Despite the landmark findings of the Assessment of Worldwide Acute Kidney Injury Epidemiology in Neonates (AWAKEN) study, the limitations of this study are notable. First, the AWAKEN study enrolled infants admitted in 2014, making the data now over 10 years old. Much has changed in neonatal practice (e.g. increased AKI awareness, treatment strategies). Secondly, the findings of the AWAKEN study were geographically limited. While the AWAKEN study was multi-national and multi-center, it represented only 24 centers (22 from North America, 1 from India and 1 from Australia). Finally, information collected from AWAKEN ended at hospital discharge. The investigators seek to leverage the strength of the Neonatal Kidney Collaborative along with other organizations and collaboratives interested in neonatal kidney health to address these gaps. Therefore, the investigators are conducting a second, modified iteration of this study entitled "AWAKEN 2.0". AWAKEN 2.0 will be a multi-center multi-national retrospective analysis utilizing similar methodology to the AWAKEN study.

Inclusion Criteria: 1. All infants born or admitted to a participating level 3 or 4 NICU between 1/1/19- 3/31/19 will be screened. 2. Infants who received intravenous fluids for \> 48 hours will be eligible. Exclusion Criteria: 1. Age \> 14 days at admission 2. Congenital heart disease requiring transfer for escalation of CHD care and/or surgery within the first 7 days 3. Lethal chromosomal anomalies 4. Neonatal mortality \