Brummitt, Charles

Introduction: Antibiotic time-outs (ATO) are a recommended antimicrobial stewardship action, but data assessing their impact are lacking. This study investigated the impact of a systematic, pharmacist initiated ATO intervention. Methods: This pre-post study included inpatients on hospitalist and intensivist services receiving empiric antibiotics for ≥48 hours. The ATO was initiated by pharmacists after 48 hours of empiric therapy and the outcome was documented including antibiotic indication, plan, and duration. An electronic medical record (EMR) alert facilitated ATO completion and pharmacists and prescribers received education prior to implementation. The primary outcome was EMR documentation of an antibiotic plan by 72 hours. Secondary outcomes included antibiotic utilization and antibiotic therapy modifications by 2 hours. Results: 399 patients were included, 199 pre- and 200 post-intervention. The most common indications were pneumonia (32%), intra-abdominal infection (20%) and urinary tract infection (19%), with no between-group differences. EMR documentation of an antibiotic plan significantly improved in the post-intervention group (19% vs. 79%, p<0.0001) as did modifications to antibiotic therapy. The median duration of in-hospital antibiotic therapy was similar between groups (4.0 vs. 4.0 days, p = 0.2499). Approximately 45% of patients in each group received discharge antibiotics and median duration of discharge antibiotic therapy prescribed was reduced (7 vs. 5 days in the pre- and post-intervention groups, respectively; p = 0.0140). Discussion: Implementation of pharmacist initiated ATO was associated with improvements in supporting EMR documentation and antibiotic therapy modifications. These findings highlight an important role in which pharmacists can serve as part of a collaborative antibiotic stewardship team.

Background: Investigations of the relationship between vancomycin trough concentrations and area under the concentration time curve (AUC) are growing, but still limited. The authors sought to determine vancomycin exposure among hospitalized adults with presumed or confirmed invasive staphylococcal infections using 2-level pharmacokinetic monitoring to inform changes to an institutional vancomycin dosing protocol. Methods: This was a retrospective observational study performed in 2 acute care hospitals. Adults prescribed vancomycin (therapeutic trough 15–20 mg/L) for a presumed or documented invasive staphylococcal infection were evaluated. Two steady-state serum vancomycin levels were used to determine each patient's 24-hour AUC to minimum inhibitory concentration ratio (AUC/MIC) using a non-Bayesian, equation-based approach. Patient demographics and crude clinical outcomes were also collected. Results: Thirty-four patients were included in the study, with 2 patients having vancomycin levels drawn twice (36 sets of levels). Most patients were located in an intensive care unit (91.2%), and 85.3% of patients were prescribed vancomycin for bacteremia, pneumonia, or endocarditis. The mean ± SD vancomycin Cmin was 16.6 ± 6.1 mg/L, and the mean AUC/MIC was 588 ± 156 mg/L × hour. The rate of 24-hour vancomycin AUC/MIC target attainment was 91.2% (n = 31/34). Of the patients with a Cmin > 9 mg/L, 100% (n = 33) achieved AUC/MIC values >400 mg/L × hour and 93.9% were >500 mg/L × hour. There was a strong correlation between vancomycin Cmin and AUC24 hr (R2 = 0.731; P < 0.001). Conclusions: Targeting a vancomycin trough between 15 and 20 mg/L frequently resulted in an AUC/MIC greater than that thought to be necessary for efficacy optimization. Considering these findings alongside the practical challenges associated with wide-scale implementation of AUC monitoring, reducing the target trough as a means to prevent vancomycin overexposure warrants clinical consideration and further evaluation.