1. 1Department of Anaesthesiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China; Department of Anaesthesia, Pain & Perioperative Medicine, Queen Mary Hospital, Hong Kong, China.
2. 2Department of Orthopaedics and Traumatology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China.
3. 3Department of Anaesthesiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China.
4. 4Department of Orthopaedics and Traumatology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China.
5. 5Department of Orthopaedics and Traumatology, Queen Mary Hospital, Hong Kong, China.
6. 6Department of Anaesthesia, Pain & Perioperative Medicine, Queen Mary Hospital, Hong Kong, China.
7. 7Department of Anaesthesia, Pain & Perioperative Medicine, Queen Mary Hospital, Hong Kong, China.
8. 8Department of Anaesthesiology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China.