Cincinnati Biorepository to Enhance the Acute Resuscitation of Cardiac Arrest Patients (Cincy BEARCATS): A Feasibility and Pilot Study.
Prehospital emergency care · 2026-02-19 · Method & validation
Abstract
OBJECTIVES: The intra-arrest stage of out-of-hospital cardiac arrest is a poorly understood syndrome. We created an emergency medical services (EMS) clinical research infrastructure to systematically study its biological pathophysiology from the earliest medical contact in the prehospital setting. Our objectives were to evaluate the feasibility of intra-arrest blood collection at two timepoints by on-duty paramedics and qualitatively describe the preliminary results of laboratory analysis. METHODS: Two urban fire-based EMS stations conducted this prospective observational pilot study. Intra-arrest patients necessitating intravenous medication administration were included. Traumatic arrests or children <8 years old were excluded. Paramedics obtained blood samples using preassembled blood collection kits immediately after intravenous access, and again after return of spontaneous circulation or resuscitative efforts were terminated on scene. Blood samples were rapidly transported, centrifuged, and frozen. Multiple pathways of biological pathophysiology were analyzed. Preexisting quality improvement activities monitored for interference with clinical care. RESULTS: Throughout the 7-month study period, there were no episodes of interference with standard clinical care during 27 patient encounters. Initial and repeat blood samples from 10 subjects had a panel of blood-based biomarker levels measured. In initial samples, we observed 6 subjects with hyperkalemia, 6 with hypernatremia, 1 with hypocalcemia, 7 with complement activation, 2 with hyperreninemia, and 1 with low antithrombin. In repeat samples, we observed renormalization of potassium in 2 subjects despite no pharmacological treatment. Complement activation, fibrin degradation products, and lactate levels increased over time in all but 1 subject. CONCLUSIONS: Serial intra-arrest blood sample collection by treating paramedics is feasible. Intra-arrest biological pathophysiology is heterogeneous.