858: Effect of Rapid Sepsis Test Adoption on Mortality, Discharge, Hospital-Free Days & Cultures in 4 Eds

Introduction: Sepsis, the leading cause of hospital death, often presents to the emergency department (ED), where diagnosis is challenging. This study evaluated the impact of a host response (HR) test as part of a quality improvement initiative in 4 EDs within a health system. Methods: An HR test generates a score stratifying sepsis risk into 3 interpretation bands [4]. It was added to the triage protocol for suspected infection at 4 EDs: Gonzales, LA (S1, 9/24/2024–6/21/2025); Lafayette, LA (S2, 9/24/2024–6/21/2025); Jackson, MS (S3, 8/27/2024–5/24/2025); and Monroe, LA (S4, 8/27/2024–5/24/2025). Ordering was initiated via nurse- and physician-driven protocols, and test-informed treatment pathways were implemented. For up to 3 months prior to test integration, outcome data was collected for patients with a screening alert. Analysis populations were stratified by sepsis status using discharge ICD-10 codes. Implementation data was aggregated at each site for 9 months. Return-adjusted hospital-free days were calculated by subtracting a patient’s length of stay for ED returns within 30 days from the original encounter, or by setting it to zero for mortalities on such returns. Results: A total of 13,972 encounters were included across the four sites: S1 (n=1966; 14%), S2 (n=3009; 22%), S3 (n=4911; 35%), and S4 (n=4086; 29%). Among tested patients, 11,228 were non-septic and 2,744 (19.6%) were septic. Following HR test integration, improvements were seen across multiple outcomes. Mortality rates declined in both non-septic (–3.6%) and septic (–7.9%) tested populations (non-septic: 10.9% [149/1368] to 7.3% [253/3639]; septic: 30.6% [107/350] to 22.7% [154/679], post-implementation, Q3). ED discharge rates improved among non-septic patients by 6.2% (18.3% [250/1368] pre vs. 24.5% [892/3639] post, Q3), with no change to ED returns. Return-adjusted hospital-free days increased in both non-septic and septic groups (non-septic: 28 to 30 days; septic: 24 to 28.5 days, post, Q3). A 14% relative reduction in blood culture orders was also observed (51% [697/1368] pre vs. 37% [1342/3639] post, Q3). Conclusions: Adding a rapid sepsis test to protocolized screening of suspected infection patients may lead to improved mortality, ED discharge, and hospital-free days with reduced resource utilization.