title: Population pharmacokinetics and dosing simulations of cefepime in septic shock patients receiving continuous renal replacement therapy.
abstract: The aim of this study was to describe the population pharmacokinetics of cefepime in septic shock patients requiring continuous renal replacement therapy and to determine whether current or alternative dosing regimens can achieve PK/PD targets. In this observational PK study, 62 samples from 13 patients were analysed using non-linear mixed-effects modelling. Different dosing regimens were evaluated using Monte Carlo simulations with ultrafiltration flow rates (UFRs) of 1000, 1500 and 2000 mL/h. The probability of target attainment was calculated against a conservative (60% T(>MIC)) and a higher PK/PD target (100% T(>MIC)) against an MIC of 8 mg/L, the clinical susceptibility breakpoint for Pseudomonas aeruginosa. A one-compartment model with between-subject variability (BSV) on clearance and volume of distribution (V(d)) described the data adequately. UFR was supported as a covariate on both parameters. Typical values for clearance and V(d) were 4.4L/h (BSV 37%) and 40.9L (BSV 20%), respectively. Dosing simulations showed failure to achieve both a conservative and a higher PK/PD target using a dose of 1g q12h for patients treated with a high UFR (≥1500 mL/h). The dose of 2g q8h or 1g q6h leads to optimal target attainment for high UFR. One gram q8h is optimal for low UFR (≤1000 mL/h). We found important variability in PK parameters. Dosing simulations show that a dose of 2g q8h or 1g q6h is needed to ensure rapid achievement of adequate levels if the UFR is ≥1500 mL/h and 1g q8h for low UFR (≤1000 mL/h).
authors.affiliation: Department of Clinical Chemistry, Microbiology and Immunology, Ghent University, Ghent, Belgium; Department of Critical Care, Ghent University, Ghent, Belgium. Electronic address: mieke.carlier@ugent.be.
authors.forename: Mieke
authors.initials: M
authors.lastname: Carlier
authors.affiliation: Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Brussels, Belgium.
authors.forename: Fabio S
authors.initials: FS
authors.lastname: Taccone
authors.affiliation: Department of Intensive Care, Erasme Hospital, Université Libre de Bruxelles (ULB), Brussels, Belgium.
authors.forename: Majorie
authors.initials: M
authors.lastname: Beumier
authors.affiliation: Department of Infectious Diseases, Erasme Hospital, Université Libre de Bruxelles (ULB), Brussels, Belgium.
authors.forename: Lucie
authors.initials: L
authors.lastname: Seyler
authors.affiliation: Department of Clinical Chemistry, Erasme Hospital, Université Libre de Bruxelles (ULB), Brussels, Belgium.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Cotton
authors.affiliation: Department of Infectious Diseases, Erasme Hospital, Université Libre de Bruxelles (ULB), Brussels, Belgium.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Jacobs
authors.affiliation: Burns, Trauma and Critical Care Research Centre, University of Queensland, Herston, Brisbane, Queensland, Australia; Royal Brisbane and Women's Hospital, Herston, Brisbane, Queensland, Australia; Institute of Translational Medicine, University of Liverpool, Liverpool, UK.
authors.forename: Jason A
authors.initials: JA
authors.lastname: Roberts
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D000077723:Cefepime; D002511:Cephalosporins / Q000008:administration & dosage* / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D015233:Models, Statistical; D010949:Plasma / Q000737:chemistry; D017582:Renal Replacement Therapy / Q000379:methods*; D012772:Shock, Septic / Q000628:therapy*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D000077723:Cefepime
keywords: Critical care; Dialysis; Dosing; ICU; β-Lactam antibiotics