Resumen La terapia antibiótica óptima en los pacientes en estado crítico puede complicarse por la alteración de la fisiología asociada a esta etapa de la enfermedad. La farmacocinética y la exposición a los antibióticos pueden verse alteradas por la enfermedad crítica subyacente y las intervenciones médicas que reciben estos pacientes en la unidad de cuidados intensivos. Además, las cepas que suelen encontrarse en la unidad de cuidados intensivos suelen ser menos susceptibles y “resistentes” a los antibióticos más habituales. De hecho, una dosificación de antibióticos que no tenga en cuenta estas diferencias únicas, probablemente fracasará y dará lugar a resultados clínicos deficientes y a la aparición de resistencia a los antibióticos en la unidad de cuidados intensivos. Los objetivos de esta revisión son describir la farmacocinética de los antibióticos betalactámicos en pacientes críticos, destacar los objetivos farmacocinéticos/farmacodinámicos para los pacientes y exponer algunas estrategias importantes que pueden optimizar la dosificación de los antibióticos betalactámicos en pacientes críticos en la unidad de cuidados intensivos.

Abstract Optimal antibiotic therapy for critically ill patients can be complicated by the altered physiology associated with critical illness. Antibiotic pharmacokinetics and exposures can be altered driven by the underlying critical illness and medical interventions that critically ill patients receive in the intensive care unit. Furthermore, pathogens that are usually isolated in the intensive care unit are commonly less susceptible and “resistant” to common antibiotics. Indeed, antibiotic dosing that does not consider these unique differences will likely fail leading to poor clinical outcomes and the emergence of antibiotic resistance in the intensive care unit. The aims of this narrative review were to describe the pharmacokinetics of beta-lactam antibiotics in critically ill patients, to highlight pharmacokinetic/pharmacodynamic targets for both non-critically ill and critically ill patients, and to discuss important strategies that can be undertaken to optimize beta-lactam antibiotic dosing for critically ill patients in the intensive care unit.

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.