Door-in-Door-Out Time at Primary Stroke Centers May Predict Outcome for Emergent Large Vessel Occlusion Patients.

Background and Purpose- Interfacility transfers for thrombectomy in stroke patients with emergent large vessel occlusion (ELVO) are associated with longer treatment times and worse outcomes. In this series, we examined the association between Primary Stroke Center (PSC) door-in to door-out (DIDO) times and outcomes for confirmed ELVO stroke transfers and factors that may modify the interaction. Methods- We retrospectively identified 160 patients transferred to a single Comprehensive Stroke Center (CSC) with anterior circulation ELVO between July 1, 2015 and May 30, 2017. We included patients with acute occlusions of the internal carotid artery or proximal middle cerebral artery (M1 or M2 segments), with a National Institutes of Health Stroke Scale score of ≥6. Workflow metrics included time from onset to recanalization, PSC DIDO, interfacility transfer time, CSC arrival to arterial puncture, and arterial puncture to recanalization. Primary outcome measure was National Institutes of Health Stroke Scale at discharge and modified Rankin Scale (mRS) score at 90 days. Results- The median (Q1-Q3) age and National Institutes of Health Stroke Scale of the 130 ELVO transfers analyzed was 75 (64-84) and 17 (11-22). Intravenous alteplase was administered to 64% of patients. Regarding specific workflow metrics, median (Q1-Q3) times (in minutes) were 241 (199-332) for onset to recanalization, 85 (68-111) for PSC DIDO, 26 (17-32) for interfacility transport, 21 (16-39) for CSC door to arterial puncture, and 24 (15-35) for puncture to recanalization. Median discharge National Institutes of Health Stroke Scale score was 5 (2-16), and 46 (35%) patients had a favorable outcome at 90 days. Complete reperfusion (modified Thrombolysis in Cerebral Ischemia 2c/3) modified the deleterious association of DIDO on outcome. Conclusions- For patients diagnosed with ELVO at a PSC who are being transferred to a CSC for thrombectomy, longer DIDO times may have a deleterious effect on outcomes and may represent the single biggest modifiable factor in onset to recanalization time. PSCs should make efforts to decrease DIDO and routine use of DIDO as a performance measure is encouraged.