Abstract 18: The Role of Vascular Imaging at Primary Stroke Centers in the Drip and Ship Paradigm

Background:In drip-and-ship protocols, vascular imaging at Primary Stroke Centers (PSC), although recommended, is not usually performed in many PSC, and its value is uncertain. Our aim was to evaluate the role of performing vascular imaging at PSC, comparing patients with vascular imaging at PSC (VI+) Vs. those without vascular imaging (VI-) in several outcomes.Methods:Observational, multicenter study from a prospective, government-mandated, population-based registry of ischemic stroke code patients firstly evaluated at a PSC from January-2016 to June-2020. We determined and compared rates of Mechanical Thrombectomy (MT) candidates transferred to CSC from all ischemic stroke codes at PSC, MT treated at CSC patients from all MT candidates transferred, and metrics related to drip-and-ship paradigm between VI + and VI- groups. A multivariate analysis to determine PSC related factors associated with receiving EVT at CSC was performed.Results:From 5792 ischemic stroke code patients at PSC, 3384 (58.4%) received a vascular imaging at PSC (VI+). Among all, 32.6% were transferred to CSC as MT candidates, and finally, 10.6% were treated with MT at CSC. The rate of transferred MT candidates was lower in the VI+ than VI- group (n: 783, 23.1% Vs. n: 1109, 46 %, p< 0.001). Among the transferred MT candidates, MT treatment at CSC was more common in the VI+ than VI- (n: 377, 48.1% Vs: n: 239, 21.5%, p<0.001). In patients transferred with baseline mild strokes (NIHSS <6), the rate of MT treated patients was higher in VI+ than VI- (n: 31, 29% Vs. n: 20, 7% p<0.001). Interval times as DIDO (median minutes 84 Vs. 81) and DTP time (188 Vs. 182) did not show differences between VI+ and VI-. In multivariate analysis adjusted by age, the independent factors associated to receiving MT at CSC were VI+ (OR: 2,128, CI95%:1,549-2,922, p<0.001), baseline NIHSS, and RACE scale.Conclusion:In the present study, performing vascular imaging at PSC diminishes unnecessary transfers to CSC and is associated with a higher probability of receiving MT at CSC in transferred patients. In mild strokes, performing a vascular imaging at PSC increases the probability of receiving MT at CSC. Metrics related to drip-and-ship model were not affected by performing a vascular imaging at PSC.