[Therapeutic monitoring of intravenous vancomycin in a pediatric critical care unit]. / Monitoreo terapéutico de vancomicina intravenosa en una unidad de paciente crítico pediátrico.

ABSTRACT

BACKGROUND: In critically ill pediatric patients vancomycin distribution and elimination is altered underscoring the need for pharmacokinetic monitoring; however the therapeutic trough ranges have not been validated for children. OBJECTIVE: To describe the pharmacokinetics of intravenous vancomycin in critically ill pediatric patients using plasmatic vancomycin monitoring. METHODS: Retrospective, descriptive study performed in a paediatric critical care unit. Vancomycin serum levels (Cmin and Cpeak), t ½ and Vd were determined in 1 month to 12 year old patients receiving ≥ 40 mg per-kg-per day. Plasmatic levels were measured at therapy onset and during follow up, evaluating the proportion of trough level determinations within therapeutic range, the average trough concentration, and the Cpeak achieved. RESULTS: A total of 65 plasmatic vancomycin monitorings were analysed in 45 patients. The average values for Ctrough, Cpeak, t1/2 and Vd were 10.4 µg/mL, 22.7 µg/mL, 3,1 h and 0.7 L/kg, respectively. An average dose of 47,1 mg/kg/day achieved initial Ctrough levels < 10 mg/mL in 60% of patients (n = 27), between 10 and 14,9 µg/mL in 22,2% (n = 10), between 15 to 20 µg/mL in 4% (n 2), and > 20 µg/mL in 13,3% (n 6). CONCLUSIONS: Vancomycin doses of 40 mg/kg/day are insufficient for critically ill paediatric patients without renal failure. A higher starting dose and monitoring of plasma levels must be considered in this population.