Single Injection Clearance in the Neonate

Abstract

The single injection clearance of inulin was compared to the standard clearance in neonates aged 1–20 days. In the first 3 days of life, the single injection method overestimated glomerular filtration rate by approximately 30%. From the 2nd week of life, values obtained by the two techniques were not significantly different. We conclude that caution should be paid when interpreting results obtained by the single injection technique during the very first days of life.

Glomerular filtration rate in the preterm infant: the relation to gestational and postnatal age

“…Only in a few patients trustworthy results can be obtained by this technique. These data are in accordance with those of Fawer et al [13].…”

Big equation for small kidneys: a newly proposed model to estimate neonatal GFR

“…This finding was ascribed to the slow rate of inulin diffusion into the extracellular space of neonates. Using the 24-h inulin infusion method as a reference value, the same author found that the single-injection method correlated poorly with GFR when the single-injection clearance was estimated over 2 h. Similarly, in 1979, Fawer et al showed that the single-injection inulin technique overestimated the urinary clearance of inulin by up to 30% in the first week of life [21].…”

Postnatale Ernährung bei sehr kleinen Frühgeborenen

“…Zusätzlich zur verminderten renalen Konzentrationsfähigkeit ist auch die glomeruläre Filtrationsfähigkeit der Niere sowie die tubuläre Rückresorption und die Cl – - und H + -Ionen-Elimination im Vergleich zu älteren Kindern geringer 8 . Dies erfordert ein vergleichsweise hohes Flüssigkeitsvolumen zur Ausscheidung von harnpflichtigen Substanzen.…”