Renal Function Assessment in Critically Ill Children

Inclusion criteria: * patients admitted to the pediatric or neonatal intensive care unit * 0 - 15 years * for neonates: gestational age ≥ 37 weeks * bodyweight \>2.5kg * intra-arterial and/or intravenous access available for iohexol administration and blood sampling Exclusion criteria: * no vascular access in place for iohexol administration and blood sampling * absence of parental/patient consent * known hypersensitivity to contrast media or previous history of adverse reaction after administration of contrast agents * known thyroid dysfunction, or for newborns: mother with known thyroid dysfunction * extracorporeal circuit (haemodialysis, extra corporal membrane oxygenation (ECMO), peritoneal dialysis) * patients with chronic kidney disease or congenital kidney anomalies * preterm neonates (gestational age \< 37 weeks) * body weight \< 2.5 kg * dehydrated newborns (i.e. loss of birth weight ≥ 10%) * planned/expected surgery with extracorporeal circulation within 5 days after inclusion