Abstract
OBJECTIVE: This study aimed to evaluate the impact of a pharmacist-led support system on the administration rate of vancomycin (VCM) loading dose, 0-24-hour area under the concentration-time curve (AUC(0-24)), incidence of acute kidney injury (AKI), and all-cause mortality in hospitalized patients. DESIGN: This retrospective study with interrupted time series analysis was conducted from January 2021 to May 2024. SETTING: A public tertiary referral center providing acute and specialized inpatient care in Japan. PATIENTS: Among the 587 hospitalized patients who received VCM during the study period, 326 were evaluated. INTERVENTION: The intervention comprised implementation of a pharmacist-led support system involving prospective prescription review and direct intervention when a VCM loading dose (25-30 mg/kg) was not prescribed. RESULTS: The loading dose administration rate increased significantly by 43.2% immediately introducing the support system (95% confidence interval: 8.40-77.90; P = 0.0156), without significant trend change thereafter. AUC(0-24) also increased significantly (241.0 vs 307.0; P < 0.001); there were no significant differences in AKI incidence or 90-day mortality. CONCLUSIONS: The support system improved the loading dose administration rate and AUC(0-24) without significantly increasing AKI or mortality. The improvement was immediate and sustained over 122 weeks, supporting its use in institutions aiming to optimize VCM loading doses where evidence remains limited.