Abstract 300: An Opportunity for Awareness: The International Academy of Emergency Medical Dispatch's Stroke Diagnostic Tool is Predictive, but Underutilized, for Hospital Confirmed Large Vessel Occlusion Strokes

Abstract

Background: Accurate identification of ischemic stroke from large vessel occlusion (LVO) by 9-1-1 professionals can facilitate prompt patient transfer to stroke centers that perform endovascular thrombectomy. We sought to determine the proportion of LVO stroke patients that were evaluated using the Medical Priority Dispatch System's (MPDS) Stroke Diagnostic Tool (SDxT). Methods: Structured, retrospective review of our institution’s stroke registry, EMS Records, and dispatch codes between January 1, 2019 and November 30, 2022. Inclusion: Adult (age >17), accessed the 9-1-1 system and transported by a ground EMS agency for an acute stroke. Exclusion: age <18, pregnant, incarcerated, cases with missing 9-1-1 data, and intracranial hemorrhage. Two trained/monitored abstractors, blinded to the study purpose, used a standardized data collection tool/dictionary to extract data. Data included MPDS codes, SDxT outcome, EMS care, demographics, hospital NIHSS score, advanced imaging, tPA administration, and mechanical thrombectomy. Primary outcome: the proportion of LVO cases that had an acute stroke (28 protocol) dispatch code. Secondary outcome: the proportion of LVO cases that that a SDxT score indicating “strong or clear evidence of a stroke”. We report proportions and 95% CI's as appropriate. Results: 60 patients met inclusion/exclusion criteria. 11/60, 18.3 % (95%CI= 10.4, 30) of the patients had complete data and a LVO. 54% were male, the median (IQR) age was 69.5 (61.3-77.5), and the median (IQR) NIHSS was 16 (5-19.75). Primary outcome: 45.5 % (95% CI= 21.3.72.0) of the LVO’s were coded as an Acute Stroke by the 9-1-1 center. Of those, 3/5 utilized the stroke diagnostic tool, all 3 of these were determined to have "Clear Evidence of Stroke". Limitations: Retrospective, unlinked data, small number of LVO's. Conclusion: When utilized, the SDxT correctly identified all LVO’s. There is an opportunity to increase awareness and utilization of the SDxT by 9-1-1 centers. Future research should focus on identifying barriers to stroke recognition and provide additional tools to address the real-life challenges our 9-1-1 communications specialists face when rapidly assessing for an acute stroke over the phone.