Abstract To analyze microbiological effectiveness of vancomycin in children from a pediatric hospital through population pharmacokinetic modelling, as well as to propose dose adjustment, a cross- sectional study was performed in children under vancomycin treatment from the John Paul II Children’s Hospital, MG. In order to establish a model, concentrations versus time curves were analyzed using a population pharmacokinetic approach with Pmetrics®. Seventeen blood samples of 10 patients were collected. The best model to describe vancomycin population pharmacokinetic (PK) consisted of a two-compartment linear intravenous absorption model. The R² value and bias for population and individuals in observed versus predicted plot was 0.642 vs. 0.992 and the bias of 0.41 mg/L and 0.0778 mg/L, respectively. The covariables creatinine clearance, age, and body mass index were related to vancomycin PK. A relevant PK variability for vancomycin in pediatric patients was verified, which was significantly influenced by creatinine clearance, age, and body mass index. This result justifies the formulation of dosing recommendations for vancomycin in pediatric patients to achieve adequate pharmacodynamics targets.

RESUMO Objetivo Adaptar um software de ajuste de dose de antibióticos inicialmente elaborado em língua inglesa para o português e a conjuntura brasileira. Métodos Trata-se de estudo observacional, descritivo, em que foi utilizado o método Delphi para estabelecer consenso entre especialistas de diferentes áreas da saúde, com perguntas que abordaram os aspectos visuais e operacionais do software. Em uma segunda etapa, foi realizado um estudo piloto, experimental, com alocação aleatória dos pacientes, para avaliação e adaptação do software em ambiente real de uma unidade de tratamento intensivo, onde foram comparadas diferenças entre pacientes que utilizaram dose padronizada usual de piperacilina/tazobactam, e os que utilizaram a dose individualizada ajustada por meio do software Individually Designed Optimum Dosing Strategies. Resultados Participaram da primeira rodada 12 profissionais cujas sugestões foram encaminhadas ao desenvolvedor do software para adequação e ajustes, e posteriormente submetidas à segunda rodada. Oito especialistas participaram da segunda rodada. Foram obtidos índices de 80% e 90% de concordância entre os juízes, caracterizando uniformidade nas sugestões. Dessa forma, houve modificação no layout do software para adequação linguística e cultural, minimizando erros de entendimento e contradições. Na segunda etapa, foram incluídos 21 pacientes, e não houve diferenças entre doses de piperacilina nos grupos dose padronizada e dose ajustada. Conclusão A versão adaptada do software é segura e confiável para seu uso no Brasil.

ABSTRACT Objective To adapt an antibiotic dose adjustment software initially developed in English, to Portuguese and to the Brazilian context. Methods This was an observational, descriptive study in which the Delphi method was used to establish consensus among specialists from different health areas, with questions addressing the visual and operational aspects of the software. In a second stage, a pilot experimental study was performed with the random comparison of patients for evaluation and adaptation of the software in the real environment of an intensive care unit, where it was compared between patients who used the standardized dose of piperacillin/tazobactam, and those who used an individualized dose adjusted through the software Individually Designed and Optimized Dosing Strategies. Results Twelve professionals participated in the first round, whose suggestions were forwarded to the software developer for adjustments, and subsequently submitted to the second round. Eight specialists participated in the second round. Indexes of 80% and 90% of concordance were obtained between the judges, characterizing uniformity in the suggestions. Thus, there was modification in the layout of the software for linguistic and cultural adequacy, minimizing errors of understanding and contradictions. In the second stage, 21 patients were included, and there were no differences between doses of piperacillin in the standard dose and adjusted dose Groups. Conclusion The adapted version of the software is safe and reliable for its use in Brazil.

RESUMO Objetivo Analisar a efetividade microbiológica considerando a correlação farmacocinética/farmacodinâmica de vancomicina em crianças e propor uma estimativa de ajuste na dose. Métodos Trata-se de um estudo observacional, transversal, realizado em hospital pediátrico, no período de 1 ano (2016 a 2017). Foram incluídas crianças de 2 a 12 anos de ambos os sexos, tendo sido excluídas crianças queimadas ou submetidas à terapia renal substitutiva. Para análise farmacocinética, foram coletadas duas amostras de 2mL de sangue total, respeitando o intervalo de 2 horas entre cada coleta. Resultados Foram incluídos dez pacientes pediátricos com idade de 5,5 anos (mediana) e intervalo interquartil (IQ) de 3,2-9,0 anos, peso de 21kg (mediana; IQ: 15,5-24,0kg) e altura de 112,5cm (mediana; IQ: 95-133cm). Apenas uma criança alcançou concentrações mínimas entre 10µg/mL e 15µg/mL. Conclusão A utilização empírica de vancomicina na população de crianças não alcançou o alvo farmacocinético/farmacodinâmico terapêutico para concentração inibitória mínima de 1μg/mL.

ABSTRACT Objective Analyze the microbiological effectiveness, based on the pharmacokinetics/pharmacodynamics correlation of vancomycin in pediatric patients, and to propose dose adjustment. Methods This is an observational, cross-sectional study, conducted in a pediatric hospital, over a 1-year period (2016 to 2017). Children of both sexes, aged 2 to 12 years, were included in the study; burn children, and children in renal replacement therapy were excluded. For the pharmacokinetic analysis, two samples of 2mL of whole blood were collected, respecting the 2-hour interval between each withdrawal. Results Ten pediatric patients with median age of 5.5 years and interquartile range (IQR) of 3.2-9.0 years, median weight of 21kg (IQR: 15.5-24.0kg) and median height of 112.5cm (IQR: 95-133cm), were included. Only one child achieved trough concentrations between 10µg/mL and 15µg/mL. Conclusion The empirical use of vancomycin in the children studied did not achieve the therapeutic pharmacokinetic/pharmacodynamic target for minimum inhibitory concentration of 1µg/mL.