[Pharmacokinetics of vancomycin in children hospitalized in a critical care unit].

INTRODUCTION: Monitoring PK/PD of vancomycin with basal and peak serum levels and the area under the curve of drug exposure 24 h/MIC (ABC 24 h/MIC) could optimize the management of children.

OBJECTIVE: To study the PK of vancomycin in children hospitalized in the Pediatric Intensive Care Unit (PICU), assessing PK/PD parameters withABC24 h/MIC.

METHODS: Retrospective, descriptive study in the PICU (Hospital Luis Calvo Mackenna) between January 2008-March 2010. We included children < 18 years who required antimicrobial treatment with vancomycin for suspected/confirmed staphylococcal infection using a dose of 40 mg/k/day. Plasmatic levels were performed one hour postinfusion and 30 min prior to the next dose. The following PK/PD parameters were calculated: vancomycin clearance, elimination rate constant, volume of distribution, half-life (T1/2) and ABC 24 h/ MIC.

RESULTS: We enrolled eighty-four children. According to ABC 24 h/MIC obtained, 54% (45/84) of children reached an optimal level (> 400 mg*hr/L). Based on the traditional PK/PD parameters, 49% of cases (41/84) presented a basal level of vancomycin in the therapeutic range (5-15 μg/mL) and of those, only 39% (16/41) had a ABC 24 h/MIC over 400 mg*h/L.

DISCUSSION: Based on our results, children admitted to PICU could be exposed to sub therapeutic doses of vancomycin. We recommend to implement tailored antimicrobial treatment monitoring vancomycin PK/PD parameters.