Personalised dosing of vancomycin: A prospective and retrospective comparative quasi‐experimental study

Aims The 2019 update to the US consensus guideline for vancomycin therapeutic monitoring advocates using Bayesian‐guided personalised dosing to maximise efficacy and minimise toxicity of vancomycin. We conducted an observational cohort study of the implementation of bed‐side Bayesian‐guided vancomycin dosing in vascular surgery patients. Methods Over a 9‐month prospective study period, vascular surgery patients were dosed vancomycin using Bayesian‐guided dosing decision tool (DoseMeRx) and compared retrospectively with a control group admitted to the same ward in the 14 months prior to the study and dosed using a standard algorithmic approach. Primary endpoints were proportion of patients achieving mean area under the curve in 24 hours (AUC 24 ) in the acceptable range 350–450 mg/L• h and percentage time in acceptable range (%TTR). Secondary endpoints focused on clinical outcomes including incidence of acute kidney injury. Results A significantly higher proportion of DoseMeRx patients achieved mean AUC 24 values in the acceptable range compared to the control group; 71/104 (68.3%) vs 58/139 (41.7%), P < .005. The median %TTR was also greater in DoseMeRx patients compared to the control group (57.1 vs 30.0%, P < .00001). Patients in the DoseMeRx group missed an average of 0.23 doses per course compared to 1.04 doses in the control group ( P < .00001). No difference was observed in secondary (clinical) outcomes between the 2 groups. Conclusion Bedside Bayesian‐guided personalised dosing of vancomycin increases the proportion of patients achieving target AUC 24 and the %TTR.