Population Pharmacokinetics of Gentamicin in Saudi Newborns during the 1st Week of Life

Introduction: Preterm birth is associated with several complications and serious infections including sepsis. Gentamicin is an important drug approved for the treatment of suspected sepsis and has extensive variable pharmacokinetics in newborns.

Objectives: To determine the pharmacokinetic parameters of gentamicin in Saudi newborns population of 92 preterm and term newborns and to identify the covariates that influences the pharmacokinetic parameters of the drug.

Methods: A total of 92 Saudi newborns were evaluated at the neonatal intensive care unit of King AbdullAziz university Hospital (Jeddah). One hundred and eighty   three serum drug concentrations were collected. Mean gestational age (GA) was 33.19 ± 2.97, weeks; mean body weight (BW) was 1.9 ± 0.63 kg. Data analysis was performed with NONMEM to evaluate these factors GA, (height) HT and gender. These factors were modeled with allometric scaling. Body weight was included as a primary covariate according to an allometric power model. One- and two-compartment models were used. Diseases (patent ductus arteriosus (PDA), Respiratory distress syndrome (RDS), sepsis) were evaluated by multiple stepwise regression using SPSS (version 16).

Results and conclusions: The two-compartment open model was  found to be better at describing gentamicin pharmacokinetics in newborns during the first week of life. Sepsis was the only disease that increased volume of distribution (Vd) significantly.