Appropriateness of Antibiotic Dosing in Patients with Augmented Renal Clearance in Cardiovascular Surgery and Coronary Intensive Care Units.

OBJECTIVE: To evaluate the appropriateness of antibiotic dosing in patients with augmented renal clearance (ARC) admitted to the cardiovascular surgery intensive care unit (CVS-ICU) and the coronary intensive care unit (CICU). STUDY DESIGN: A descriptive study. Place and Duration of the Study: CVS-ICU and CICU, Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkiye, from January 2024 to January 2025. METHODOLOGY: Adult patients (≥18 years) hospitalised for ≥24 hours, diagnosed with ARC (eGFR ≥130 mL/min/1.73 m2), and receiving antibiotics were included. Dosing appropriateness was assessed based on UpToDate® recommendations. ARC risk was stratified using the ARC scoring system. Data were analysed using descriptive statistics, chi-square test, and Mann-Whitney U test. RESULTS: Of the 3,334 screened patients, 83 (2.5%) met ARC criteria; 57 received antibiotics and were included in the analysis. At least one dosing error was identified in 84.2% of cases, mostly underdosing (73.1%). The most common antibiotics were cefazolin (42.6%), ampicillin-sulbactam (14.6%), and daptomycin (7.3%). A high ARC risk score was associated with a greater likelihood of dosing errors (90.4% vs. 66.6%; OR = 4.7, p = 0.044). Patients with dosing errors were younger (median 25.5 vs. 50 years, p = 0.004) and received more antibiotics (p = 0.038). CONCLUSION: Although ARC was uncommon, dosing errors were frequent. Early recognition of ARC and individualised dosing are critical to optimise therapy in ICU patients. KEY WORDS: Augmented renal clearance, Antibiotic dosing, Cardiovascular surgery intensive care unit, Coronary intensive care unit, Dose adjustment.