391: Vancomycin Pharmacokinetics and Dosing in Critically Ill Patients on Crrt: A Scoping Review

Introduction: Acute kidney injury is common in critically ill patients, and continuous renal replacement therapy (CRRT) is frequently used in this population. CRRT significantly alters drug pharmacokinetics (PK), including vancomycin, an antibiotic with a narrow therapeutic window. Existing studies show inconsistent PK findings and dosing recommendations, complicating standardized dosing. To address this, we conducted a scoping review to evaluate the literature on vancomycin PK and dosing in critically ill adults receiving CRRT. Methods: A scoping review following PRISMA guidelines was conducted. Relevant studies from inception to December 2024 were identified using Ovid MEDLINE via PubMed, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov. Studies were included if they were English-language involving critically ill adults on CRRT and evaluating vancomycin PK or dosing through single-dose, multiple-dose, or population PK analyses. Two authors independently screened studies, with one performing final review. An AI tool (ChatGPT, OpenAI) was used to assist in editing the abstract for length and clarity. All content was reviewed and verified by the authors. Results: Ninety-eight studies were identified, of which 22 met inclusion criteria. Vancomycin clearance (Cl) ranged from 1.5 – 4.6 L/hr, with CRRT often accounting for ≥50% of total Cl. CRRT modality and intensity were key determinants of vancomycin Cl. Volume of distribution ranged from 0.38 – 1.4 L/kg. Population PK studies showed high interindividual variability. Dose simulation studies support model-informed precision dosing, recommending a loading and maintenance dose of 10 – 15 mg/kg/day, or a fixed dose of 1500 – 1750 mg/day. Conclusions: Vancomycin dosing in CRRT patients is highly variable due to significant PK alterations. Guidelines do not address this variability, underscoring the need for individualized dosing, therapeutic drug monitoring, and potentially model-informed approaches. Future studies should focus on validating personalized strategies and linking PK/pharmacodynamic targets with outcomes.