Abstract WP41: Mobile Stroke Unit Operational Performance: A Retrospective Single Institution Analysis And Meta-Analysis

Introduction: Mobile stroke units (MSU) have become increasingly common and now span a diverse range of communities. Reporting has previously focused on clinical outcomes, and metrics reporting the operational performance of MSUs have not been standardized. The aim of this study was to establish normalized metrics to evaluate MSUs and to a complete a meta-analysis of the current literature on MSU performance. Methods: Our MSU serves a population of 741,000 people in upstate New York. Data was prospectively collected and retrospectively analyzed from its inception in October of 2018 through March of 2021. We report rates of transportation/dispatch and MSU utilization rates. MEDLINE and Cochrane Library databases were utilized to perform a meta-analysis. Pooled rates of tPA/dispatch, tPA/day, mechanical thrombectomy (MT)/dispatch and MT/day were calculated. An assessment of inter-study heterogeneity was also completed. Results: In 606 days, our MSU was dispatched 1,719 times for an average rate of 2.8 dispatches/day. 324 patients (18.8%) were transported to the hospital by the MSU. Intravenous tPA was administered in 64 patients (3.7% of all dispatches) and the rate of tPA/day was 0.317 (95% CI 0.150 to 0.567). MT was performed in 24 patients (1.4% of dispatches) for a MT/day rate of 0.119 (95% CI 0.074 to 0.163). Of the 290,760 total minutes the MSU was available, it was in use for 38,742 minutes (13.3% utilization rate). Our meta-analysis included 18 total articles. Eight studies were included in the pooled analysis of tPA/dispatch (342/5,862) for a rate of 7.2% (95% CI 4.8% to 9.5%, I2 = 92%) and nine were included in the analysis of tPA/day (785/1,998) for a rate of 0.359 (95% CI 0.150 to 0.567, I2 = 99%). Seven studies met criteria for analysis of MT/dispatch (102/5,335) for a rate of 2.0% (95% CI 1.2% to 2.8%, I2 = 67%) and for MT/day (103/1,249) for a rate of 0.092 (95% CI 0.046 to 0.138, I2 = 91%). Conclusions: Future studies investigating MSUs should focus on the following normalized metrics: tPA/dispatch, tPA/day, MT/dispatch, MT/day, and the newly described utilization rate. These normalized metrics are also useful at an institutional level when evaluating the overall utilization and efficacy of an MSU.