1 Department of Anesthesiology, American University of Beirut-Medical Center, Beirut, Lebanon.
2 Intensive Care Unit, Hospital Morales Meseguer, Murcia, Spain.
3 Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, American University of Beirut-Medical Center, Beirut, Lebanon.
4 Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, American University of Beirut-Medical Center, Beirut, Lebanon. pb05@aub.edu.lb.