Acute Kidney Injury in the PICU

Acute kidney injury (AKI) is a sudden decline of glomerular filtration rate, loss of kidney function, and reduction in urine output (UO) that may have different causes, levels of severity, and variable persistence over time. AKI is a common event in all hospitalized patients, with varying incidence rates according to age. The pediatric and neonatal settings offer a variety of challenges for a correct and timely diagnosis of AKI. Difficulties in establishing normal values for serum creatinine (SCr) and UO in healthy children, variations due to maternal creatinine, limitations in daily blood sampling, and the difficult UO estimation, indicate the need for specific tools in this population, especially in the first days and weeks of life. Heart failure due to congenital heart abnormalities, intraoperative or post-surgical renal blood flow reduction in cardiac surgery setting, graft versus host disease, and sinusoidal obstruction syndrome following hematopoietic stem cell transplantation are considered typical clinical conditions that may be complicated with severe AKI in the pediatric intensive care unit (PICU). Although not always easy to recognize, pediatric and neonatal AKI is a common event and, alike in the adult population, an independent risk factor for increased length of hospital stay, long-term complications, and mortality.