1. Department of Anaesthesiology and Critical Care; Hospital Clínico Universitario; Valencia Spain
2. CIBER de Enfermedades Respiratorias; Instituto de Salud Carlos III; Madrid Spain
3. Department of Anesthesiology; Hospital Privado de Comunidad Mar de Plata; Mar de Plata Argentina
4. Deparment of Intensive Care; Hospital Universitario La Princesa; Madrid Spain