EMS Data Linked Project: Stroke in South Carolina

BACKGROUND:  Although stroke mortality rates have declined significantly for the last three decades, South Carolina’s rate remains relatively high. Located in the buckle of the stroke belt, SC stroke mortality rate ranked third highest in the county, according to the latest available data¹. Despite the fact that 49% of all stroke mortality occurred pre-transport², there is an urgent need to study those who are transported for acute stroke care. The SC Department of Health and Environmental Control (DHEC) has compiled 100% of 2010 EMS run data and linked them with the facility discharge files. The purposes of this study are to:

• enumerate the length of time from 911call to destination,
• evaluate the impact of EMS transportation in improving stroke identification, and treatment of acute stroke and
• examine the rate of intravenous tissue plasminogen activator (IV-tPA) use and its correlates.

METHODS:  A retrospective analysis was conducted of the statewide EMS database linked with statewide hospital discharge records. Patients transported via EMS were compared with patients not transported by EMS.  Variables considered included patient demographics, transportation time, location or type of destination hospital, and treatment with IV-tPA.

RESULTS: In 2010, 18,962 hospitalized patients in SC were assigned a primary discharge diagnosis of stroke. Of these, 36% (6,824) were transported via EMS. The average time from 911call to hospital arrival was 44.6 minutes.  About 48% of all stroke patients were treated in primary stroke centers (PSCs), and 4.3% of all ischemic patients received thrombolytic therapy.  EMS identification of stroke signs and symptoms was associated with shorter transfer times and a higher transfer rate to a PSC than patients whose symptoms were not identified as stroke by EMS (50% vs. 43% for all strokes, P<0.001; 50% vs. 41% for ischemic strokes, P<0.001).  For patients with ischemic stroke, EMS identification of stroke resulted in a markedly higher tPA treatment rate (10.9%) than cases whose symptoms were not identified as stroke by EMS (3.6%) and cases arriving by private vehicles (3.5%, P<0.001).  

CONCLUSIONS:  EMS identification of stroke signs and symptoms was associated with increased rate of transportation to PSCs and increased fibrinolytic treatment for ischemic stroke. Younger stroke patients, EMS transport, treatment in a PSC, and living in an urban county increased the likelihood of receiving IV-tPA. Increasing the community’s utilization of EMS and raising their awareness of the nearest PSCs location and designation may increase the rate of IV-tPA use and better stroke outcome.