Introduction: Treatment for large vessel occlusion is profoundly time dependent. Two potential mechanisms to reduce time to treatment are optimizing transfers from Primary Stroke Centers (PSC) and transporting selected patients directly to a Comprehensive Stroke Center (CSC). In our region, we sequentially implemented both interventions. We sought to evaluate the impact of 1) Optimization of PSC transfer protocols and 2) implementation of a severity based EMS triage protocol on times to treatment and outcomes.
Methods: All thrombectomy patients in our state treated over 24 months were retrospectively reviewed. We included patients with anterior circulation LVO, presenting within 6 hours, with an NIHSS of 6 or higher. An EMS protocol was introduced such that patients with a field LAMS score of 4 or higher, within 30 minutes of the CSC, would be directly transported to the CSC. Patients from adjacent states (where the EMS protocol would not apply) as well as inpatient strokes were excluded. We examined the proportion of patients who were directly transported to the CSC, as well as trends in time to treatment with IV tPA and thrombectomy from the time of first hospital arrival (PSC or CSC). Time periods were as follows: 7/1/2015 to 12/31/2015 (Pre-optimization and pre-triage); 1/1/2016 to 12/31/2016 (PSC optimization; pre-triage) and 1/1/2017 to 6/30/2017 (PSC optimization and triage). Primary outcome measures were times to treatment, discharge to home, and in-hospital mortality.
Results: The results are summarized in the table below. Marked decreases in median time from first hospital arrival to recanalization were seen, from 156 to 109 minutes over time. In addition, there were increases in discharge home, and decreases in in-hospital mortality across each of the time periods.
Conclusions: Through a combination of field triage and optimization of PSC workflow, it is possible to reduce times to thrombectomy and improve outcomes across an entire region.