Abstract Body: Introduction: Delaware (DE) is comprised of 3 counties, with 7 hospitals within the stroke system. The state’s only CSC located in the northernmost county receives transfers from 1 PSC midway in the state and 3 PSCs in the southernmost county (figure 1). Historically PSC door time to CSC skin puncture time by interfacility transport can range from 3.5 to >5 hours from the furthest DE PSC. Utilizing ground EMS and Delaware State Police (DSP) helicopter EMS (HEMS) transport, DE developed a process to identify potential acute LVO patients and transport directly to the CSC to reduce time to mechanical thrombectomy (MT).

Methods: In November 2022, DE EMS Standing Orders changed the pre-hospital stroke evaluation tool from RACE to the Visual, Aphasia, Neglect (VAN) assessment. DE EMS identified patients who were VAN+ and utilized HEMS for direct transport to the CSC statewide.
If EMS identified a VAN+ patient in Kent or Sussex counties, the local PSC medical control approved for direct CSC transport while considering thrombolytic timing.
DSP met the ground EMS crews at a pre-designated landing zone to receive the patient.
Ground EMS notified the CSC to prepare for the standard stroke alert evaluation.
Results: From January 2023 to June 2024, 183 patients were flown by DSP HEMS directly to the CSC bypassing a PSC.
Of those, 59% had a final diagnosis of stroke (AIS and nontraumatic ICH/SAH)
Of those with AIS, 60% were positive for an LVO
Of those patients with LVO, MT was completed on 71%, compared to rate of 52% in prior years
Kent County: EMS arrival to skin puncture median time was 2.00 hours compared to 3.75 hours for interfacility transfer from the PSC.
Sussex County: EMS arrival to skin puncture median time was 2.5 hours compared to 4.00 hours for interfacility transfer time from the 2 Sussex PSCs combined (figure 2).
Statewide the median time for EMS arrival to skin puncture for patients who were MT candidates was 2.25 hours vs 3.88 hours, 1.6 hours faster than PSC to CSC transferred patients.
CSC time includes obtaining imaging which may already have been completed at the PSC for interfacility transfers.

Conclusion: Early LVO patient identification and pre-hospital helicopter EMS transport directly to the CSC reduced the time from EMS arrival to skin puncture for MT patients in Delaware by 1.6 hours. This was 41% faster compared to those arriving at the CSC via interfacility transfer from PSC, and increased the rate of thrombectomy on eligible patients by 19%.