Evaluation of pharmacist time dedicated to vancomycin dosing in adult patients using a 24-hour AUC nomogram or trough monitoring approach: A time motion study

Abstract

Purpose: Evidence-based guideline recommendations for vancomycin dosing recently shifted from a trough-based strategy to an area under the curve (AUC) approach. While several AUC dosing methods exist, the optimal approach has not been determined. Literature characterizing time requirements for various vancomycin dosing strategies remains limited.

Methods: A time and motion study was conducted to measure the time spent by clinical pharmacists dosing vancomycin using an AUC nomogram. Pharmacists who dosed and monitored vancomycin for adult patients on the general medical ward (GMW) or intensive care unit (ICU) of a large academic medical center consented to study participation. Vulnerable patients and vancomycin orders for surgical infection prophylaxis were excluded. The primary outcome was the median amount of time clinical pharmacists dedicated to vancomycin-related clinical activities during an 8-hour weekday shift. Secondary outcomes included the proportion of patients prescribed vancomycin at the beginning of each shift and factors contributing to greater than average time spent on vancomycin-related responsibilities.

Results: Seven clinical pharmacists collected data on 178 vancomycin orders. The estimated amount of time a clinical pharmacist spent on daily vancomycin responsibilities averaged 10.45 minutes (interquartile range [IQR], 6.94-15.8 minutes). The overall median time requirement per vancomycin assessment was 3.45 minutes (IQR, 1.95-6.7 minutes). The only factor independently associated with prolonged dosing time was follow-up dosing from a previous day.

Conclusion: The study elucidated time requirements associated with an AUC nomogram-based vancomycin dosing approach. This data could be used to compare time requirements associated with other existing vancomycin dosing strategies, which may help healthcare systems determine the optimal AUC dosing method for their specific practice model.

Keywords: area under curve; methicillin-resistant Staphylococcus aureus; pharmacists; pharmacokinetics; time and motion studies; vancomycin.