Development of the Three Antimicrobial Stewardship E's (TASE) Framework and Association Between Stewardship Interventions and Intended Results Analysis to Identify Key Facility-Specific Interventions and Strategies for Successful Antimicrobial Stewardship

Background. Successful antimicrobial stewardship (AS) interventions have been described previously. Currently, a uniform operational approach to planning and implementing successful AS interventions does not exist. From 2015 to 2019, concomitant vancomycin and piperacillin-tazobactam use (CVPTU) for >48 hours at Vanderbilt University Medical Center (VUMC) significantly decreased through AS efforts. We analyzed the interventions that led to this change and created a model to inform future intervention planning and development. Methods. Adult admissions at VUMC from January 2015 to August 2019 were evaluated for CVPTU. The percentage of admissions receiving CVPTU for >48 hours, the primary outcome, was evaluated using statistical process control charts. We created the Three Antimicrobial Stewardship E's (TASE) framework and Association between Stewardship Interventions and Intended Results (ASIR) analysis to assess potential intensity and impact of interventions associated with successful change during this time period and to identify guiding principles for development of future initiatives. Results. The mean percentage of admissions receiving CVPTU per month declined from 4.2% to 0.7%. Over 8 time periods, we identified 4 periods with high, 3 with moderate, and 1 with low intervention intensity. Continuous provider-level AS education was present throughout. Creation and dissemination of division and department algorithms and reinforcement via computerized provider order entry sets preceded the largest reduction in CVPTU and sustained prescribing practice changes. Conclusions. The TASE framework and ASIR analysis successfully identified pivotal interventions and strategies needed to effect and sustain change at VUMC. Further research is needed to validate the effectiveness of this framework as a stewardship intervention planning tool at our institution and others.