Antimicrobial dosing in patients with renal dysfunction

Many antimicrobials used in critically ill patients are predominantly eliminated by the kidneys. Optimizing dosing in this population is challenging as renal clearance is often altered by changes in organ function and presence of extracorporeal circuits. Extrapolating dosing recommendations derived from noncritically ill populations to these patients may not adequately account for these pharmacokinetic changes, increasing the risk of subtherapeutic or toxic drug exposures. This review summarizes contemporary strategies for optimizing antimicrobial dosing in critically ill patients, with a focus on renal dysfunction.

In resource-limited settings, dosing nomograms developed from critically ill populations provide a practical and effective approach to improving antimicrobial target attainment. Therapeutic drug monitoring is increasingly recommended for a wider range of antimicrobials and can identify patients who require dose optimization. Model-informed precision dosing software has shown promise in improving antimicrobial exposures, although data supporting its impact on clinical outcomes are lacking. Emerging technologies for optimizing antimicrobial dosing include dosing software with artificial-intelligence and real-time monitoring of antimicrobial concentrations with biosensors.

Alterations in renal clearance are a major contributor to suboptimal antimicrobial exposure in critical illness. Selection of dose optimization strategies should be guided by local resources and expertise (see Graphical Abstract).