ABSTRACT NUMBER: ESOC2026A587 FEASIBILITY OF PREHOSPITAL GFAP POINT-OF-CARE TESTING IN AMBULANCE VEHICLES FOR EARLY DETECTION OF INTRACEREBRAL HEMORRHAGE (PRETECT 1)

Abstract Background and aims Prehospital identification of intracranial hemorrhage (ICH) in patients with suspected acute stroke or reduced level of consciousness is highly relevant for triage and early management. Recent studies demonstrated promising diagnostic performance of glial fibrillary acidic protein (GFAP) using in-hospital point-of-care testing on prehospital blood samples. PRETECT-1 is the first study to evaluate the feasibility of prehospital GFAP testing directly in ambulance vehicles. Methods From 06/2024 to 10/2025, patients with suspected acute stroke (≤6 hours) or reduced consciousness (any time window) were enrolled in a cooperative study with regional emergency medical services. Plasma GFAP was measured in the prehospital phase using a mobile centrifuge and the i-STAT Alinity(Abbott) system. Feasibility outcomes included availability of GFAP results before hospital admission, before brain imaging and occurrence of technical failures. Diagnostic reference was the final diagnosis (ICH vs. other diagnoses). Results 152 patients (mean age 72.8 ± 16.2 years) were included; 24 patients were diagnosed with ICH vs.128 patients with other diagnoses (mostly ischemic stroke; median GFAP 319 [94.5–1782] vs. 50.5 [29–78.5] pg/mL). Mean time from blood sampling to GFAP result was 31.7 ± 20.0 minutes. GFAP results were available before hospital admission in 41.6% of cases (median time difference 0 minutes [−9 to +10]). Overall, 84.4% of results were available prior to CT. Technical issues occurred in 19 cases. Conclusions Prehospital GFAP testing in ambulances is feasible and frequently provides results before hospital admission and imaging. Centrifugation and technical failures limited efficiency, supporting the transition to whole-blood cartridges in the on-going PRETECT-2 trial. Conflict of interest Christian Foerch reports a patent issued for GFAP for identification of intracerebral hemorrhage licensed to Banyan Biomarkers; grants from Keep fighting foundation; and grants from AstraZeneca. The other authors: nothing to disclose.