Abstract WP234: Improved Response, Neurologic Evaluation, and Treatment Timing With a Mobile Stroke Unit in a Large Urban Population

Abstract

Background: The University of Colorado Mobile Stroke Unit (UC MSU) began clinical operation in January 2016, providing ambulance-mounted CT scanning and tele-stroke neurologic assessment in the Denver, CO, metropolitan area. As one of the first U.S. tertiary stroke centers to utilize a mobile stroke protocol we sought to evaluate characteristics of response, neurologic evaluation, and treatment of the MSU. Methods: The study assessed patient, stroke, ambulance response, neurologic evaluation, and treatment characteristics of the UC MSU for its initial year in service. Variables included time from stroke alert (MSU dispatch) to brain CT in the field, treatment decision, tPA administration, and transport to a hospital stroke center. Time intervals from last seen normal were calculated for all patients. Study variables were compared for patients treated with thrombolysis on the MSU, and those who were not; and with reported times for other MSUs, and hospitals. Results: Between Jan. 15, 2016 and Jan. 9, 2017, 47 individuals received prehospital management with the UC MSU. Median age was 67 years (IQR 58-77), and 51% were female. Median initial NIH Stroke Scale score was 5 (IQR 2-11), and 36% were moderate to severe (NIHSS ≥8). Thirteen (28%) of patients were treated with IV tPA on the MSU. Median times from stroke alert to MSU arrival on the scene and first CT were 7 minutes (IQR 5-8), and 20 minutes (IQR 18-24), respectively. Median time to tPA administration was 39 minutes (IQR 35-45) from stroke alert, and 52 minutes (IQR 48-77) from the last time the patient was seen normal. Times from stroke alert and last seen normal to arrival at a stroke hospital were a median of 51 minutes (IQR 45-54) and 71 minutes (IQR 56-118), respectively. Conclusions: In this study of the initial year of an urban MSU’s operation, time intervals from stroke alert to initial brain CT imaging, neurologic evaluation and administration of thrombolysis were found to be substantially reduced compared to conventional, hospital-based stroke protocols, and some earlier MSUs. Intervals from last seen normal to these procedure time points were similarly reduced. These results suggest prehospital management with an MSU has potential to aid the goal of earlier thrombolysis after ischemic stroke symptom onset.