(618) Overnight Review of Rapid Blood Culture Identification Results by Intensive Care Unit Pharmacists

Introduction: The BioFire® Blood Culture Identification 2 (BCID2) is a rapid multiplex blood culture identification panel. BCID2 in combination with Antimicrobial Stewardship Program (ASP) interventions can decrease time to antimicrobial optimization and mortality. At our institution ASP reviews BCID2 results on weekdays during business hours, potentially delaying interventions to optimize treatment. Overnight intensive care unit (ICU) pharmacists began reviewing overnight BCID2 results in September 2022. The purpose of this study was to evaluate the impact of overnight ICU pharmacist review on time to BCID2 review and time to accepted antimicrobial order changes in concordance with ASP guidance.

Methods: This was a retrospective cohort study of ICU patients with BCID2 results during overnight ICU pharmacist coverage (2100-0700) from August 1, 2021 to August 31, 2022 (pre-cohort), and September 1, 2022 to September 30, 2023 (post-cohort). The primary outcome was time from BCID2 result to ASP or overnight ICU pharmacist review. Secondary outcomes included type of documented intervention, accepted interventions, time to accepted antimicrobial order changes, types of accepted antimicrobial order changes, empiric antimicrobial concordance with final susceptibilities, 30-day mortality, and 30-day readmission. Descriptive statistics were calculated, and outcomes were compared using independent sample t-tests, Chi-square, and Fisher’s exact tests.

Results: This study included 422 overnight BCID2 results with 192 in the pre-cohort and 230 in the post-cohort. Baseline characteristics were similar between groups. Time to BCID2 review was significantly reduced in the post-cohort compared to the pre-cohort (mean time 11.6 hours vs. 21 hours, P < 0.001). A higher proportion of patients had documented interventions in the post-cohort compared to the pre-cohort (51.3% vs. 39.1%, P = 0.01). The time to antimicrobial order change was significantly reduced in the post-cohort (2.7 hours vs. 10.5 hours, P = 0.04). No statistically significant differences were observed in effective empiric antimicrobial therapy, 30-day mortality, or 30-day readmission.

Conclusions: This study demonstrates the added benefit of overnight pharmacist review of rapid diagnostics to improve time to antimicrobial interventions.