Implementation of an Intervention to Improve Blood Culture Stewardship in 14 Adult ICUs and Wards.

Importance: Data are limited on factors associated with successful implementation of diagnostic stewardship interventions to improve blood culture (BCx) ordering in adult inpatients. Objective: To evaluate the impact of a quality improvement (QI) initiative to improve BCx ordering and to evaluate factors associated with improved practices. Design, Setting, and Participants: We conducted a pragmatic QI initiative over a one-year period in seven acute care academic hospitals in the United States. A total of 14 adult units, seven intensive care units (ICUs) and seven wards from each hospital were included. The study was conducted between April st 2022 and June 30th, 2024. Data analysis was performed March 1st to October 25th, 2026. Intervention: The QI included implementation of an evidence-based BCx algorithm with indications for blood cultures, education on the algorithm, and monitoring and feedback of BCx practices. Outcomes and Measures: The primary outcome was BCx utilization (BCU) 12 months before and after implementation. Using the Consolidated Framework for Implementation Research, we assessed implementation through interviews with QI teams, diaries of QI activities completed by each team, and a survey of frontline providers. Coincidence analysis was used to identify implementation factors associated with improvement in BCU. Results: Four ICUs had significantly lower BCU (~20% reduction), one of them also had a 50% increase in BCx positivity. Greater baseline BCx inappropriateness was associated with significant reduction in BCU. Two wards had a significant increase in BCU, one of which had a concomitant increase in BCx positivity. An additional ward had a 60% increase in BCx positivity despite similar BCU before and after QI implementation. Coincidence analysis identified several factors associated with improved BCU, including perceptions that the algorithm was easy to use and reduced unnecessary repeat BCx, as well as nurse inclusion in educational activities and regular education and feedback on BCx practices. Conclusion: Baseline BCU should inform the design and focus of BCx stewardship initiatives. Effective improvement efforts require multifaceted implementation strategies.