Abstract WP78: Large Vessel Occlusion Triage and Routing Utilized for Long-Distance Stroke Transports by Emergency Medical Services (LVO TRUST EMS)

Abstract

Introduction: Endovascular treatment (EVT) is the most effective therapy in acute ischemic stroke (AIS) with large vessel occlusion (LVO) but its practice is limited to comprehensive stroke centers (CSC). Previous studies have suggested that trained Emergency Medical Services (EMS) professionals can successfully detect LVO cases using a validated screening tool. For these cases, direct transfer to CSC bypassing community hospitals could lead to better outcomes. Methods: This is a retrospective cohort study from 01/01/2018-12/31/2022 of patients with suspected stroke transported by EMS providers from 14 community agencies (primarily fire paramedics) in Southeastern Massachusetts (EMS Region V). When stroke was suspected, EMS providers applied the Field Assessment Stroke Triage for Emergency Destination (FAST-ED) score to assess severity. Bypass of local community hospitals for direct transport to CSC was generally considered for patients with FAST-ED ≥4 and approval of the Region V EMS Medical Director, with the goal of early intervention for severe strokes. In addition to standard education on the use of the FAST-ED score, the EMS agencies received annual aggregate performance feedback and individual case feedback (when requested) from the CSC. Data were collected from the Electronic Health Record (EHR) on demographics, comorbidities, final diagnoses, FAST-ED scores, NIHSS and acute treatments. Descriptive statistics were performed to describe the accuracy of diagnosis and rates of treatment. Results: Among 166 triaged patients to go directly to CSC, 57.6% (95/166) were diagnosed with AIS, and 61.1% (58/95) of them were found to have LVO. There was a higher proportion of AIS or intracranial hemorrhage (ICH) in cases with higher FAST-ED scores. Only 23.4% (39/166) of the cases were diagnosed with stroke mimics, primarily related to lower FAST-ED scores. In total, 36.9% of patients with AIS received EVT: thrombectomy with standard window tPA (21.1%) or late presenter tPA (LKW ≥ 4.5 h, 1.1%), and without tPA (14.7%). Conclusions: A diverse group of community-based EMS services in Southeastern Massachusetts using a prehospital tool can identify patients with severe stroke, i.e. AIS due to LVO or ICH, with acceptable diagnostic accuracy.