1. Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
2. Department of Oral Biology and Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
3. Department of Dentistry, Uttaradit Hospital, Uttaradit, Thailand
4. Department of Anesthesiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
5. Department of Anesthesiology, Lamphun Hospital, Lamphun, Thailand
6. Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand