1 Department of Cardiothoracic and Vascular Anesthesia, General Hospital "G. Papanikolaou", Chortiatis, 57010, Thessaloníki, Greece. dodasarri@yahoo.gr.
2 Department of Anaesthetics, Guy's and St Thomas' NHS Foundation Trust, London, UK. dodasarri@yahoo.gr.
3 Department of Respiratory Medicine, G. Papanikolaou Hospital, Thessaloníki, Greece.
4 Intensive Care Unit, Department of Anesthesiology and Intensive Care, AHEPA University Hospital of Thessaloniki, Aristotle University of Thessaloniki, Thessaloníki, Greece.