Alberto Braghiroli1, Giuseppe Insalaco2, Antonio M Esquinas3. 1. Division of Respiratory Disease, Salvatore Maugeri Foundation, IRCCS, Scientific Institute of Veruno, Veruno, Italy. alberto.braghiroli@fsm.it. 2. National Research Council of Italy-Institute of Biomedicine and Molecular Immunology "A. Monroy", Palermo, Italy. 3. Intensive Care and Non Invasive Ventilatory Unit, Hospital Morales Meseguer, Murcia, Spain.