1. Department of Anesthesia and Intensive Care Copenhagen University Hospital ‐Bispebjerg and Frederiksberg Copenhagen Denmark
2. Department of Clinical Medicine University of Copenhagen Copenhagen Denmark
3. Section for Transfusion Medicine, Capital Region Blood Bank, Rigshospitalet Copenhagen University Hospital Copenhagen Denmark
4. Department of Anesthesia and Intensive Care Zealand University Hospital Køge Denmark
5. Section of Biostatistics University of Copenhagen Copenhagen Denmark
6. Department of Anesthesia and Trauma Center, Centre of Head and Orthopedics Copenhagen University Hospital – Rigshospitalet Copenhagen Denmark