1 Department of Anaesthesiology, Pain Medicine and Critical Care, R. G. Kar Medical College, Kolkata, West Bengal, India.
2 Intensive Care Unit, Hospital Morales Meseguer, Murcia, Spain.
3 Department of Anaesthesiology and Critical Care, Institute of Post Graduate Medical Education and Research/S.S.K.M. Hospital, Kolkata, West Bengal, India. drmcmandal@gmail.com.