Koch, Birgit C P

ABSTRACT Beta‐lactam antibiotics (beta‐lactams) are first‐line treatments for most major infectious syndromes in acutely ill patients, with in vitro activity against common pathogens, demonstrated efficacy in trials, and a perceived low risk of adverse effects. The current dosing approach, informed by population‐level data, tends to be simplistically reduced to a “one size fits all” dosing method which only accounts for body weight (i.e., in pediatrics) and end organ function to estimate drug clearance (e.g., estimated glomerular filtration rate); this approach results in substantial variability in observed serum concentrations in acutely ill patients, which can compromise real‐world effectiveness and safety. Beta‐lactam dose individualization, therefore, defined as a dosing regimen for one patient informed by measured concentrations from that patient, has been recommended in international clinical guidelines. Comprehensive guidance on best practices for beta‐lactam dose individualization is lacking. To address this knowledge gap and develop guidance, a multidisciplinary panel of international experts was assembled from the disciplines of infectious diseases, critical care, pharmacometrics, and laboratory medicine, representing both adults and pediatrics. The panel systematically evaluated the literature, using the GRADE approach where feasible, to address broad thematic questions pertaining to whether beta‐lactam dose individualization should be pursued, for what indications beta‐lactam dose individualization is warranted, and the most critical considerations and best practices for implementation of beta‐lactam individualization. The resultant consensus recommendations will equip healthcare professionals caring for acutely ill patients treated with beta‐lactam therapy with the evidence and tools necessary to guide optimal use of beta‐lactam dose individualization.

Due to extensive pathophysiological changes in critically ill patients, standard dosing of antibiotics may lead to inadequate drug exposure. This is concerning, as insufficient plasma drug concentrations may lead to treatment failure, whereas excessive drug exposure may increase the risk of toxic adverse events. The role of inflammation as a factor influencing the pharmacokinetics (PK) and pharmacodynamics (PD) of antibiotics remains largely unknown. PK/PD target attainment of antibiotics can be improved through therapeutic drug monitoring, i.e., measurement of drug concentrations in the blood with subsequent dosage adjustment to reach a certain target. Besides, population PK models may be used to predict drug exposure and tailor dosing in an individual patient (model‐informed precision dosing). Inflammatory biomarkers have been proposed to measure inflammation levels and guide antibiotic treatment. However, their potential to guide antibiotic dosing is unclear. This narrative review describes associations between inflammation and PK/PD of antibiotics in critically ill patients, and the role of biomarkers, therapeutic drug monitoring and model‐informed precision dosing in improving antibiotic dosing. A focus of future research should be on the interplay between inflammation and PK/PD of antibiotics by including inflammatory biomarkers in PK/PD models and using big data to predict antibiotic exposure in critically ill patients.