J Cravo1, A C Pazarli2, A M Esquinas3. 1. Serviço de Pneumologia A, Centro Hospitalar e Universitário de Coimbra, Praceta Prof. Mota Pinto, 3000-075, Coimbra, Portugal. jcravo87@gmail.com. 2. Department of Chest Diseases, Elbistan State Hospital, Kahramanmaraş, Turkey. 3. Intensive Care and Non Invasive Ventilatory Unit, Hospital Morales Meseguer, Murcia, Spain.