Population Kinetics of Gentamicin in Neonates
Willi Weber , Gabriele Kewitz, Michael Looby , Manfred Nitz , Lutz Harnisch, Ludwig Rost
Clinical Pharmacology and Neonatology Clinic, Free University of Berlin Klinikum Steglitz, Hindenburgdamm 33 1000 Berlin 45, Federal Republic of Germany
Summary : A population kinetic analysis was carried out on sparse Gentamicin (GE) data collected from 469 neonates as part of a a routine therapeutic drug monitoring (TDM ) program for the hospital neonatology unit. The best predictors of the kinetic parameters of the monoexponential model, volume of distribution (VD) and clearance (CL), were the neonates weight (WT) and gestational age (GA). VD is related only to WT, whereas the half-life is only related to the GA. The clinical implications of the findings are that the initial dose per WT administered to premature infants should be larger than that for term infants because of a larger VD per WT and the dose intervals between the maintenance doses extended due to the prolonged half-life. Apart from these general guidelines, specific dose recommendations are given.