The "Network Effect" on Interfacility Transfers Among Regional Stroke Certified Hospitals

Timely inter-facility transfer of thrombectomy-eligible patients is a mainstay of Stroke Systems of Care. We investigated transfer patterns among stroke certified hospitals in the Dallas-Fort Worth (DFW) Metroplex (19 counties, 9,286 sq mi, > 7.7 million people), by hospital network and stroke center status.

We conducted a North Central Texas Trauma Regional Advisory Council (NCTTRAC) Stroke Regional Care Survey at all 44 centers involved in the treatment of MT-eligible ischemic stroke patients between June-September 2019, with a response rate of 100%. All hospitals identified network status, stroke designation - Acute Stroke Ready Hospital (ASRH), Primary Stroke Center (PSC), Comprehensive Stroke Center (CSC) - and geographic location. Stroke Assessment and Large Vessel Occlusion (LVO) screening tool use was evaluated. The distance between the sending and receiving facility was calculated using GPS coordinates. If the closest CSC was not used, the average distance between the selected and the closest CSC was geospatially mapped via R statistical analysis software (Vienna, Austria) gmapsdistance package.

Of the 44 facilities, 6 were ASRHs, 27 were PSCs, 11 were CSCs. Seventy-seven percent (n=34) belonged to one of four hospital networks. All facilities used stroke assessment tools; 57% completed LVO screening. There was significant heterogeneity in inter-facility transfer patterns with no regional standardization. Seventeen percent of ASRHs (n=1) and 56% of PSCs (n=15) conducted inter-facility transfers using ground transportation via EMS. Sixty percent of non-network facilities transferred to the closest CSC. Of the remaining 40%, the average distance between the closest and the selected CSC was 1.5 miles (min max 0.2-2.9 miles). Seventeen percent of network facilities transferred to the closest CSC. Among the remaining 83%, the average distance between the closest and the selected CSC was 4.1 miles (min-max 1-8 miles).

Non-network facility status increased the likelihood of transfer to the closest Comprehensive Stroke Center. Transfer distance variability among network facilities may contribute to delays in reperfusion therapy.