[1] Univ Sains Malaysia, Sch Med Sci, Dept Anaesthesiol & Intens Care, Kubang Kerian, Kelantan, Malaysia
[2] Hosp Univ Sains Malaysia, Dept Anaesthesiol & Intens Care, Kubang Kerian, Kelantan, Malaysia
[3] Univ Sains Malaysia, Sch Med Sci, Biostat & Res Methodol Unit, Kelantan, Malaysia
[4] Natl Univ Hlth Syst, Natl Univ Hosp, Dept Med, Div Resp & Crit Care Med, Singapore, Singapore
[5] Univ Sains Malaysia, Sch Med Sci, Dept Anaesthesiol & Intens Care, Kubang Kerian 16150, Kelantan, Malaysia