[1] Hosp Clin Univ, Unidad Cuidados Intensivos Resp, Valencia, Spain
[2] Univ Autonoma Madrid, Hosp Univ La Princesa, Madrid, Spain
[3] Univ Texas Hlth Sci Ctr San Antonio, S Texas Vet Hlth Care Syst, Audie L Murphy Div, San Antonio, TX 78229 USA
[4] Hosp Clin Barcelona, Unidad Vigilancia Intensiva & Intermedia Resp, Serv Neumol, Inst Torax,IDIBAPS, Barcelona, Spain
[5] Corp Sanitaria Parc Tauli, Barcelona, Spain
[6] VHIR Univ Autonoma Barcelona, UCI, Hosp Univ Vall dHebron, CibeRes, Barcelona, Spain
[7] Hosp Univ Gran Canaria Dr Negrin, Las Palmas Gran Canaria, Spain