[1] Command Hosp Eastern Command, Dept Anesthesiol & Crit Care, Kolkata, West Bengal, India
[2] All India Inst Med Sci, Dept Neuroanaesthesiol & Crit Care, New Delhi, India
[3] All India Inst Med Sci, Dept Emergency Med, New Delhi, India
[4] All India Inst Med Sci, Neurosci Ctr, Dept Neuroanaesthesiol & Crit Care, New Delhi, India