Abstract 2940: Arrival in the Emergency Department on Nights and Weekends Results in Delayed Administration of Intravenous Thrombolysis for Ischemic Stroke

Background: Reduced time to administration of intravenous thrombolysis for acute ischemic stroke (AIS) is associated with improved functional outcomes. Less than one-third of AIS patients receive IV rt-PA with a door-to-needle (DTN) ≤ 60 minutes with only modest improvements reported over time. We investigated factors that may adversely prolong DTN time including reduced resident physician experience, low stroke severity on presentation, patient presentation time (day, evening, night) and day of week. Methods: A consecutive series of 258 patients with AIS received IV rt-PA at an academic comprehensive stroke center with a developed process for IV rt-PA administration and a neurology training program. Patient presentation times in the emergency department were divided into shifts defined as 07:00-14:59 (day), 15:00-22:59 (evening) and 23:00-06:59 (night). Neurology resident experience level was grouped as July-December (less experienced) vs. January-June (more experienced). Day of the week was grouped into weekday (Monday-Friday) and weekend (Saturday-Sunday). Variables associated with DTN time were assessed by t-test, ANOVA and by logistic regression. Results: The group had a mean age of 70.7±14.3 years, NIHSS score 13.3±6.8, DTN time 70.0±28.1 minutes, onset to ED arrival time 77.5±38.0 minutes. Patients presenting during evening and night hours had prolonged DTN times, day=65.5, evening=71.8 and night=78.3 minutes (p=0.05) by ANOVA. Patients arriving on weekends also had prolonged DTN times weekdays= 66.6 vs. weekends=77.2 minutes (p=.01). Increased time from onset to ED arrival was also associated with reduced DTN time (p<0.001). Age, gender, race, stroke severity on presentation, and resident experience level were not related to DTN time. Both presentation time by shift and day of week were predictive of prolonged DTN time by multivariable analysis (p<0.01). Conclusions: Presentation time during the evening and night hours and weekends is associated with prolonged DTN times. Reduced staffing and support on nights and weekends may adversely affect DTN time.