Abstract WP250: Transport Times and Door to Needle Times for Stroke Patients Transported by EMS

Abstract

Background: Treatment of acute ischemic stroke with intravenous thrombolytics (IV tPA) within the therapeutic window is more likely achieved when there is rapid activation of emergency medical services (EMS), identification of stroke, direct transport to Acute Stroke-Ready Hospitals, and expedited ED evaluation. Objective: To characterize the relation between EMS treatment interval and door to needle times in a regional stroke system of care. Methods: This is a retrospective analysis of consecutive patients with positive prehospital stroke screens transported to an approved stroke center in a large metropolitan system from January 2011 to December 2014. Data, including EMS on scene time, ED arrival time, and time of IV tPA administration, was abstracted from the regional EMS Agency stroke database. The median times from EMS arrival on scene to ED arrival (scene to door) and from ED arrival to IV tPA (door to needle) were calculated along with the total scene to needle time. The correlation coefficient was calculated between scene to door and door to needle time. Results: Among 16,317 patients transported for suspected stroke, the median age was 75 (Interquartile range [IQR] 62-85) years, 53% were women, 66% White, 11% Asian, 10% Black and 24% Hispanic. 84% had a cerebrovascular final diagnosis, ischemic stroke (IS) being the most common (n=8606, 53%). 16% had a non-stroke-related diagnosis. The median NIHSS was 9 (IQR 4 to 19). Median scene to door time was 29mins (IQR 23-38). IV tPA was administered to 1655 patients (19% with final diagnosis of IS), with 84% treated within 3hrs of LWKT (median=128mins, IQR 99-165). Among patients receiving IV tPA, the median scene to door time was 28mins (IQR 22-36), door to needle time 92mins (IQR 68-98) and scene to needle time 116mins (IQR 89-126). There was no correlation between scene to door and door to needle time (r=-0.0014). Conclusions: In this large metropolitan region, scene to door times for stroke transports averaged just under 30mins and scene to needle times just under 2hrs. There was no correlation between scene to door and door to needle times. These findings provide data to guide efforts to reduce first responder to final treatment intervals throughout regional EMS stroke systems.