Estimation of renal function in critically ill neonates, infants and children
Pieter De Cock, PharmD, PhD
BACKGROUND: In critically ill children, renal function is constantly fluctuating as a result of underlying disease processes, changing hemodynamic status and therapeutic interventions. Acute kidney injury (AKI) as well as augmented renal clearance (ARC) are common (prevalence AKI : 15-82%; ARC: 60%). Both are associated with increased morbidity and mortality. GAP: Although accurate estimation of renal function is crucial in critically ill children, to date, this remains a journey of the beaten track. HYPOTHESIS: Determination of glomerular filtration rate (GFR) is generally used for quantification of renal function. Despite its broad use, we hypothesize that commonly used creatinine-based methods for estimation of GFR are not reliable in critically ill children. This study aims to identify the most reliable bedside GFR estimation method and quantitatively describe the intrapatient (time-dependent) variability in GFR. METHODS: A prospective, interventional trial at the neonatal and pediatric ICU, Ghent University Hospital (Belgium) is performed. Glomerular filtration rate is measured by calculation of iohexol plasma clearance (golden standard for GFR estimation). Accuracy and sensitivity of different estimation methods (by urinary creatinin clearances and serum biomarker-based GFR equations, amikacin clearance) are studied. RESULTS: Pending IMPACT: Accurate and sensitive renal function estimation methods (RFEM) provide an invaluable tool to guide drug dosing and fluid management in the critically ill child with rapidly changing renal function. To date, there is a lack of scientific evidence on the optimal RFEM to be used. Moreover, this study will give an insight on the necessary frequency for GFR estimation/biomarker measurement in routine clinical care.