Intraosseous or Intravenous Vascular Access for Out-of-Hospital Cardiac Arrest.

Autor:	Vallentin MF; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Granfeldt A; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Klitgaard TL; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Mikkelsen S; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Folke F; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Christensen HC; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Povlsen AL; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Petersen AH; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Winther S; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Frilund LW; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Meilandt C; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Holmberg MJ; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Winther KB; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Bach A; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Dissing TH; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Terkelsen CJ; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Christensen S; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Kirkegaard Rasmussen L; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Mortensen LR; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Loldrup ML; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Elkmann T; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Nielsen AG; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Runge C; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Klæstrup E; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Holm JH; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Bak M; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Nielsen LR; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Pedersen M; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Kjærgaard-Andersen G; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Hansen PM; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Brøchner AC; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Christensen EF; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Nielsen FM; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Nissen CG; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Bjørn JW; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Burholt P; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Obling LER; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Holle SLD; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Russell L; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Alstrøm H; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Hestad S; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Fogtmann TH; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Buciek JUH; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Jakobsen K; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Krag M; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Sandgaard M; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Sindberg B; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark., Andersen LW; From Prehospital Emergency Medical Services, Central Denmark Region (M.F.V., A.L.P., A.H.P., S.W., L.W.F., C.M., K.B.W., A.B., T.H.D., L.K.R., L.R.M., M.L.L., T.E., A.G.N., C.R., L.W.A.), the Department of Clinical Medicine, Aarhus University (M.F.V., A.G., C.J.T., S.C., L.W.A.), and the Departments of Anesthesiology and Intensive Care (A.G., M.J.H., T.H.D., S.C., C.G.N., B.S., L.W.A.), Cardiology (C.J.T.), and Radiology (E.K.), Aarhus University Hospital, Aarhus, the Department of Anesthesiology and Intensive Care, Aalborg University Hospital (T.L.K., F.M.N.), the Center for Prehospital and Emergency Research, Department of Clinical Medicine, Aalborg University and Aalborg University Hospital (E.F.C.), and Emergency Medical Services, North Denmark Region (P.B.), Aalborg, the Prehospital Research Unit (S.M., P.M.H.) and Emergency Medical Services (J.H.H., M.B., L.-G.R.N., M.P., G.K.-A., P.M.H.), Region of Southern Denmark, the Department of Anesthesiology and Intensive Care, Odense University Hospital (J.H.H., M.B.), and the Department of Regional Health Research, University of Southern Denmark (A.C.B.), Odense, the Departments of Cardiology (F.F.) and of Anesthesiology and Intensive Care (L.R.), Copenhagen University Hospital, Gentofte Copenhagen University Hospital-Emergency Medical Services, Ballerup (F.F., J.W.B., H.A., S.H., T.H.F.), the Department of Clinical Medicine, University of Copenhagen (F.F., H.C.C., L.R., M.K.), and the Department of Cardiology, the Heart Center, Copenhagen University Hospital, Rigshospitalet (L.E.R.O., S.L.D.H.), Copenhagen, the Prehospital Center, Region Zealand, Næstved (H.C.C.), the Department of Anesthesiology and Intensive Care, Gødstrup Regional Hospital, Gødstrup (L.K.R.), the Department of Anesthesiology and Intensive Care, Randers Regional Hospital, Randers (L.R.M., T.E.), the Department of Anesthesiology and Intensive Care, Viborg Regional Hospital, Viborg (A.G.N.), the Elective Surgery Center, Silkeborg Regional Hospital, Silkeborg (C.R.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Esbjerg and Grindsted, Esbjerg (L.-G.R.N.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Kolding (M.P., A.C.B.), the Department of Anesthesiology and Intensive Care, University Hospital of Southern Denmark, Aabenraa (G.K.-A.), the Department of Anesthesiology and Intensive Care, Svendborg Hospital, Svendborg (P.M.H.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital, Herlev (H.A.), the Department of Anesthesiology and Intensive Care, Copenhagen University Hospital-North Zealand, Hillerød (S.H.), the Department of Anesthesiology and Intensive Care, Zealand University Hospital, Køge (J.U.H.B.), the Department of Anesthesiology and Intensive Care, Nykøbing Falster Hospital, Nykøbing Falster (K.J.), the Department of Anesthesiology and Intensive Care, Holbæk Hospital, Holbæk (M.K.), and the Department of Anesthesiology and Intensive Care, Slagelse Hospital, Slagelse (M.S.) - all in Denmark.
Jazyk:	angličtina
Zdroj:	The New England journal of medicine [N Engl J Med] 2024 Oct 31. Date of Electronic Publication: 2024 Oct 31.
DOI:	10.1056/NEJMoa2407616
Abstrakt:	Background: Out-of-hospital cardiac arrest is a leading cause of death worldwide. Establishing vascular access is critical for administering guideline-recommended drugs during cardiopulmonary resuscitation. Both the intraosseous route and the intravenous route are used routinely, but their comparative effectiveness remains unclear. Methods: We conducted a randomized clinical trial to compare the effectiveness of initial attempts at intraosseous or intravenous vascular access in adults who had nontraumatic out-of-hospital cardiac arrest. The primary outcome was a sustained return of spontaneous circulation. Key secondary outcomes were survival at 30 days and survival at 30 days with a favorable neurologic outcome, defined by a score of 0 to 3 on the modified Rankin scale (scores range from 0 to 6, with higher scores indicating greater disability). Results: Among 1506 patients who underwent randomization, 1479 were included in the primary analysis (731 in the intraosseous-access group and 748 in the intravenous-access group). The successful establishment of vascular access within two attempts occurred in 669 patients (92%) assigned to the intraosseous-access group and in 595 patients (80%) assigned to the intravenous-access group. Sustained return of spontaneous circulation occurred in 221 patients (30%) in the intraosseous-access group and in 214 patients (29%) in the intravenous-access group (risk ratio, 1.06; 95% confidence interval [CI], 0.90 to 1.24; P = 0.49). At 30 days, 85 patients (12%) in the intraosseous-access group and 75 patients (10%) in the intravenous-access group were alive (risk ratio, 1.16; 95% CI, 0.87 to 1.56); a favorable neurologic outcome at 30 days occurred in 67 patients (9%) and 59 patients (8%), respectively (risk ratio, 1.16; 95% CI, 0.83 to 1.62). Prespecified adverse events were uncommon. Conclusions: There was no significant difference in sustained return of spontaneous circulation between initial intraosseous and intravenous vascular access in adults who had out-of-hospital cardiac arrest. (Funded by the Novo Nordisk Foundation and others; IVIO EU Clinical Trials Register number, 2022-500744-38-00; ClinicalTrials.gov number, NCT05205031.). (Copyright © 2024 Massachusetts Medical Society.)
Databáze:	MEDLINE
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