Cheng-Wei Lu,1,2 Kuo-Chen Chang1 1Department of Anesthesiology, Far Eastern Memorial Hospital, New Taipei, 220, Taiwan; 2Department of Mechanical Engineering, Yuan Ze University, Taoyuan, 320, TaiwanCorrespondence: Cheng-Wei Lu, Department of Anesthesiology, Far Eastern Memorial Hospital, 21, Section 2, Nan-Ya South Road, Banqiao District, New Taipei, 220, Taiwan, Tel +886 2 89667000, ext. 2383, Fax +886 2 23680782, Email drluchengwei@gmail.com
Lu et al. (Wed,) studied this question.