Abstract No. 540 Mechanical thrombectomy for emergent large-vessel occlusions (ELVO) in the era of the Field Assessment Stroke Triage for Emergency Destination (FAST-ED): a retrospective cohort assessment at a comprehensive stroke center

Abstract

The FAST-ED is a verified pre-hospital screening tool for patients suspected of having an emergent large vessel occlusion (ELVO). It allows for early triaging of patients to comprehensive stroke centers for emergent comprehensive stroke treatment. We set out to study the effect of this pre-hospital triaging tool at a single center comprehensive stroke center. Institutional records of pre-hospital stroke alerts and FAST-ED scores were queried over a 17-month period. FAST-ED data was acquired from a single regional Fire and Rescue Team as implementation of the FAST-ED scoring metric was non-uniform across the regional emergency medical services (EMS). Demographic and clinical data was assessed including admission National Institute of Health Stroke Scale (NIHSS), incidence of mechanical thrombectomy, length of hospitalization as well as treatment metrics including time to catheterization. Between January 2017 and May 2018, 432 stroke alerts were activated of which 251 were generated by EMS, and 164 (65.3%) had documented FAST-ED scores. Among total pre-hospital stroke alerts, age distribution was 69.7 years±15 (mean±SD), and female predominance was 50.2%. In the 17 months, 28 patients received mechanical thrombectomy, and 21.5% received rT-PA (54 patients). In our analysis, overall median (IQR) FAST-ED and NIHSS scores were 3 (4) and 9 (16) respectively. Interestingly 95% of mechanical thrombectomies were performed on patients with FAST ED scores ≥ 4, and 96.4% on patients with NIHSS ≥ 5. The FAST-ED pre-hospital scoring metric is a useful tool as an adjunct to the NIHSS in the diagnosis of emergent large vessel occlusion. In the right setting it can be useful in optimizing treatment paradigms and improve time to treatment in these patients.