Abstract DP089: Using the ROSIER Scale to Decrease Acute Stroke Activations in a Municipal Hospital Emergency Department

Background: Appropriately identifying strokes among patients presenting acutely with neurologic symptoms is a challenge in the emergency department (ED). Acute stroke activations (ASA), while essential for ensuring prompt care, are also resource intensive. As treatment timelines and eligibility expand, the volume of false-positive ASA (stroke mimics) have increased. Because rates of stroke mimics are higher among patients presenting to the ED as walk-ins rather than via Emergency Medical Services (EMS), we sought to determine whether using the ROSIER scale (RS), a validated tool for stroke triage screening, could reduce false-positive ASA for walk-ins. The RS is a 7-item stroke recognition tool, which incorporates clinical history and neurological signs, and ranges from -2 to +5 with scores ≥1 suggestive of stroke. Methods: We retrospectively reviewed consecutive ASA patients presenting to the ED within 6h from last known well (LKW) from 1/1/2024-6/30/2025. Data was abstracted from the extant medical record with an RS score determined based on triage documentation for all walk-ins, and final diagnosis (stroke/TIA/ICH versus stroke mimic) determined by expert consensus for all ASA blinded. An RS≥1 was considered a positive screen in accordance with prior literature. Descriptive statistics were used to describe our findings and standard tests of comparison to compare groups with alpha set at