1. Department of Critical Care Medicine, University Hospital Carlos Haya, 29018 Malaga, Spain
2. University of Malaga School of Medicine, Spain
3. Department of Critical Care Medicine, Santiago Hospital, Vitoria, Spain
4. Department of Critical Care Medicine, Hospital 12 de Octubre, Madrid, Spain
5. Department of Critical Care Medicine, Centro Hospitalario de Porto, Portugal
6. Department of Critical Care Medicine, Hospital Municipal de Necochea, Argentina