FAST-ED scale smartphone app-based prediction of large vessel occlusion in suspected stroke by emergency medical service

Abstract

Background and Purpose: Considering the highly time-dependent therapeutic effect of endovascular treatment in patients with large vessel occlusion–associated acute ischemic stroke, prehospital identification of large vessel occlusion and subsequent triage for direct transport to a comprehensive stroke center offers an intriguing option for optimizing patient pathways. Methods: This prospective in-field validation study included 200 patients with suspected acute ischemic stroke who were admitted by emergency medical service to a comprehensive stroke center. Ambulances were equipped with smartphones running an app-based Field Assessment Stroke Triage for Emergency Destination scale for transmission prior to admission. The primary measure was the predictive accuracy of the transmitted Field Assessment Stroke Triage for Emergency Destination for large vessel occlusion and the secondary measure the predictive accuracy for endovascular treatment. Results: A Field Assessment Stroke Triage for Emergency Destination ⩾4 revealed very good accuracy to detect large vessel occlusion–related acute ischemic stroke with a sensitivity of 82.4% (95% confidence interval = 65.5–93.2), specificity of 78.3% (95% confidence interval = 71.3–84.3), and an area under the curve c-statistics of 0.89 (95% confidence interval = 0.85–0.94). Field Assessment Stroke Triage for Emergency Destination ⩾4 correctly identified 84% of patients who received endovascular treatment [73.5% specificity (95% confidence interval = 66.4–79.8)] with an area under the curve c-statistics of 0.82 (95% confidence interval = 0.74–0.89). In a hypothetical triage model of an urban setting, one secondary transportation would be avoided with every fifth patient screened. Conclusion: A smartphone app-based stroke triage completed by emergency medical service personnel showed adequate quality for the Field Assessment Stroke Triage for Emergency Destination to identify large vessel occlusion–associated acute ischemic stroke. We demonstrate feasibility of the use of a medical messaging service in prehospital stroke care. Based on these first results, a randomized trial evaluating the clinical benefit of such a triage system in an urban setting is currently in preparation. Clinical Trial Registration: https://clinicaltrials.gov Unique identifier: NCT04404504.

Emergency medical service utilization and timely treatment among acute ischemic stroke patients in Beijing from 2018 to 2021

“…According to the results, though EMS utilization was not associated with the proportion of patients receiving endovascular therapy within 90 min, the adjusted time for imaging-to-puncture and door-to-puncture was significantly shorter in the EMS group. Recent research has developed and validated various tools to identify large vessel occlusion strokes in the prehospital setting enabling rapid triage and timely treatment of patients [27][28][29][30][31][32]. Efforts for prehospital risk identification for eligible endovascular patients in the EMS system may further optimize endovascular therapy and improves outcomes [33][34][35][36][37][38].…”

Prehospital stroke management and mobile stroke units

“…The results showed that its use improved door-to-CT times for 215 intervention patients as compared with 389 controls [27 min (18-44) vs. 71 min (43-147); P ¼ 0.0001] [35]. Similarly, a further study found that an application-based stroke scale used on smartphones in the field achieved good accuracy in detecting LVO [36].…”