Neuron-specific enolase measured in serum compared to plasma for neuroprognostication in out-of-hospital cardiac arrest​Yusuf A. Isse Christian Hassager Jacob E. Møller Ruth Frikke-Schmidt Benjamin Nyholm Frederik T. Søndergaard Johannes Grand Simon Mølstrøm Laust E. R. Obling Rasmus P. Beske Henrik Schmidt Jesper Kjaergaard Martin A. S. Meyer a Department of Cardiology, The Heart Center, Copenhagen University Hospital, Rigshospitalet, Denmarkb Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmarkc Department of Clinical Research, University of Southern Denmark, Odense, Denmarkd Department of Cardiology, Odense University Hospital, Odense, Denmarke Department of Clinical Biochemistry, Center of Diagnostic Investigation, Copenhagen University Hospital, Copenhagen, Denmarkf Department of Anesthesiology, Odense University Hospital, Odense, Denmarkg Department of Cardiothoracic Anesthesiology, The Heart Center, Copenhagen University Hospital, Rigshospitalet, Denmarkon January 10, 2026 at 1:50 am