1. Department of Cardiothoracic Surgery/Cardiac Anaesthesia & ICU Section, Heart Hospital, Hamad Medical Corporation, P.O. Box 3050, Doha, Qatar
2. Department of Critical Care Medicine, Beni Suef University, Beni-Suef 62511, Egypt
3. Department of Anesthesia, Al-Azhar University, Cairo 11651, Egypt
4. Department of Medical Research, Hamad Medical Corporation, P.O. Box 3050, Doha, Qatar