1. Faculty of Medicine, Universiti Sultan Zainal Abidin, Kuala Terengganu, Malaysia
2. Department of Anaesthesiology and Intensive Care, Hospital Pengajar Universiti Sultan Zainal Abidin, Kuala Nerus, Malaysia
3. Department of Anesthesiology and Pain Medicine, Seoul National University Hospital, Seoul, Korea
4. Department of Anesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul, Korea