1. Department Anesthesiology, Surgical-Trauma Intensive Care and Pain Clinic, Hospital Clínic Universitari, University of Valencia, 46010 Valencia, Spain
2. Anesthesiology and Intensive Care Department, Consorcio Hospital General Universitario, 46014 Valencia, Spain
3. Anesthesiology and Intensive Care Department, Hospital Universitario Ramón y Cajal, 28034 Madrid, Spain
4. Surgical Critical Care Department, Hospital Universitario La Paz, 28046 Madrid, Spain
5. Anesthesiology and Surgical Critical Care Department, Hospital Universitario De La Princesa, 28006 Madrid, Spain