Reliability of Field Assessment Stroke Triage for Emergency Destination Scale Use by Paramedics: Mobile Stroke Unit First-Year Experience

Abstract

Background and Purpose: Field Assessment Stroke Triage for Emergency Destination (FAST-ED) scale is a helpful tool to triage patients with stroke in the field. However, data on its reliability in the prehospital setting are lacking. We aim to test the reliability of FAST-ED scale when used by paramedics in a mobile stroke unit covering a metropolitan area. Methods: As part of standard operating mobile stroke unit procedures, paramedics initially evaluated patients. If the event characterized a stroke alert, the FAST-ED score was determined by the paramedic upon patient contact (in-person) and then independently by a vascular neurologist (VN) immediately after paramedic evaluation (remotely/telemedicine). This allowed testing of the interrater agreement of the FAST-ED scoring performance between on-site prehospital providers and remotely located VN. Results: Of a total of 238 patients transported in the first 15 months of the mobile stroke unit’s activity, 173 were included in this study. Median age was 63 (interquartile range, 55.5–75) years and 52.6% were females. A final diagnosis of ischemic stroke was made in 71 (41%), transient ischemic attack in 26 (15%), intracranial hemorrhage in 15 (9%), whereas 61 (35%) patients were stroke mimics. The FAST-ED scores matched perfectly among paramedics and VN in 97 (56%) instances, while there was 0 to 1-point difference in 158 (91.3%), 0 to 2-point difference in 171 (98.8%), and 3 or more point difference in 2 (1.1%) patients. The intraclass correlation between VN and paramedic FAST-ED scores showed excellent reliability, intraclass correlation coefficient 0.94 (95% CI, 0.92–0.96; P <0.001). When VN recorded FAST-ED score ≥3, paramedics also scored FAST-ED≥3 in majority of instances (63/71 patients; 87.5%). A large vessel occlusion was identified in 16 (9.2%) patients; 13 occlusions were identified with a FAST-ED≥3 while 3 were missed. All of the latter patients had National Institutes of Health Stroke Scale score ≤5. Conclusions: We demonstrate excellent reliability of FAST-ED scale performed by paramedics when compared with VN, indicating that it can be accurately performed by paramedics in the prehospital setting.

Assessment of Clinical Scales for Detection of Large Vessel Occlusion in Ischemic Stroke Patients from the Dijon Stroke Registry

“…Such a gap may contribute to a poorer performance of the scales in the pre-hospital phase compared with their performance during an in-hospital evaluation due to difficulties in identifying subtle neurological impairment. However, a recent study showed an excellent reliability in the FAST-ED score obtained by paramedics compared with the score obtained by vascular neurologists [39], thus suggesting that differences in modalities of clinical evaluation may have only a minor impact on our findings. Finally, our study was based on a limited number of patients with LVO, thus limiting its power.…”

Prehospital stroke management and mobile stroke units

“…LVO patients in the intervention group ( n = 240) had better management metrics and better outcomes than did LVO patients in the pre-intervention group (34.6 vs. 23.7%; P = 0.014) [21]. Similarly, use of an LVO scale has been studied in a telemedicine-equipped MSU, with positive effects [22].…”

Direct Transfer to the Neuroangiography Suite for Patients With Stroke

“…While they can be administered swiftly and reliably in the prehospital setting, the sensitivity and specificity of these scales are variable and have achieved only moderate success in discriminating stroke mimics from strokes. 27–29 Furthermore, no clinical scale can meaningfully differentiate hemorrhagic from ischemic stroke (particularly LVO stroke) and so neuroimaging remains paramount in diagnosis. Identifying the type and etiology of stroke can be a diagnostic challenge for the DTA approach.…”