1. Department of Anaesthesiology; Herlev Hospital; Copenhagen University Hospital; Herlev Denmark
2. Department of Anaesthesia and Intensive Care Medicine; Gentofte Hospital; Copenhagen University Hospital; Gentofte Denmark
3. Department of Anaesthesia; Centre of Head and Orthopaedics; Rigshospitalet; Copenhagen University Hospital; Copenhagen Denmark
4. Arthroscopic Center Amager; Department of Orthopedic Surgery; Amager - Hvidovre; Copenhagen University Hospital; Copenhagen Denmark
5. Department of Anaesthesia; Amager - Hvidovre; Copenhagen University Hospital; Copenhagen Denmark
6. Section of Acute Pain Management; Rigshospitalet; Copenhagen University Hospital; Copenhagen Denmark