The purpose of this study was to determine the influence of weight with
gentamicin assay error on the Bayesian and nonlinear least squares regression analysis in 12 Korean
appendicitis patients.
Gentamicin was administered intravenously over 0.5 h every 8 h. Three specimens were collected at 48 h after the first dose from all patients at the following times, just before regularly scheduled infusion, at 0.5 h and 2 h after the end of 0.5 h infusion. Serum
gentamicin levels were analyzed by fluorescence polarization immunoassay technique with TDxFLx. The standard deviation (SD) of the assay over its working range had been determined at the serum
gentamicin concentrations of 0, 2, 4, 8, 12, and 16 microg/mL in quadruplicate. The polynominal equation of
gentamicin assay error was found to be SD (microg/mL) = 0.0246 - (0.0495C) + (0.00203C2). There were differences in the influence of weight with
gentamicin assay error on pharmacokinetic parameters of
gentamicin using the nonlinear least squares regression analysis but there were no differences on the Bayesian analysis. This polynominal equation can be used to improve the precision of fitting of pharmacokinetic models to optimize the process of model simulation both for population and for individualized pharmacokinetic models. The result would be improved dosage regimens and better, safer care of patients receiving
gentamicin.