Validation of Vancomycin Dosing Guidance During Transition of Care

Abstract

Vancomycin is an antibiotic commonly used to treat serious gram-positive infections. Patients requiring prolonged therapy in Singapore routinely receive intermittent vancomycin infusion in the hospital and are switched to continuous infusion for outpatient parenteral antibiotic therapy. During this transition of care, there may be a risk of not achieving therapeutic targets. We evaluated the performance of a model-based dosing algorithm in achieving a therapeutic target within 7 days of care transition. A published population pharmacokinetic model was used as the foundation to guide vancomycin dosing when discharging inpatients on intermittent infusion to outpatient care on continuous infusion. Selected demographic variables (age, weight, and creatinine clearance) were used to devise initial dosing. Patients with guided dosing were compared with historic controls (dosing by clinicians alone). The primary outcome of the study was to achieve vancomycin steady-state concentration of 20-25 mg/L. Compared with historic controls, the proportion of patients attaining a therapeutic target by day 7 was significantly improved (6 of 19 [31.6%] vs 12 of 17 [70.6%], P =.04). Our model-based approach could guide customized dosing to facilitate switching patients from intermittent to continuous infusion during transition of care. Further validation in a larger patient cohort is warranted.