Antimicrobial pharmacokinetics and stewardship in critically Ill adult patients receiving ECMO: Challenges, evidence, and future directions

Infection is a common indication and complication for extracorporeal membrane oxygenation (ECMO), and adult ECMO recipients face increased nosocomial infection risk. Effective antimicrobial dosing in these patients remains difficult due to pharmacokinetic (PK) and pharmacodynamic (PD) alterations driven by critical illness and extracorporeal circuits. In this narrative review we aim to discuss the potential impact of ECMO on antimicrobial PK and dosing requirements. Findings across studies show heterogeneity in dosing practices and indicate that inter-patient variability is influenced more by critical illness and organ dysfunction than ECMO alone. Standardized dosing protocols remain lacking, and in the absence of robust guidelines, current best practice involves applying PK/PD principles, using therapeutic drug monitoring, and individualizing dosing strategies. Across all antimicrobial drug classes, robust prospective studies linking PK/PD targets to clinical outcomes are lacking. Future research should focus on prospective trials correlating dosing regimens with meaningful clinical endpoints to refine evidence-based antimicrobial guidance. These efforts are essential to developing evidence-based dosing recommendations and optimizing antimicrobial stewardship in this high-risk population.