[1] Univ Autonoma Barcelona, Inst Univ Parc Tauli, CIBER Enfermedades Resp, Serv Med Intens,Hosp Sabadell,Corp Sanitaria Parc, E-08193 Barcelona, Spain
[2] Hosp Burgos, Serv Med Intens, Burgos, Spain
[3] Hosp Univ Gen Castellon, Serv Med Intens, Castellon de La Plana, Spain
[4] Hosp SAS Jerez, Serv Cuidados Crit & Urgencias, Cadiz, Spain
[5] Hosp Valle De Hebron, Inst Recerca, Barcelona, Spain
[6] Consorci Sanitari Terrasa, Barcelona, Spain
[7] Clin USP Palmaplanas, Serv Med Intens, Palma De Mallorca, Spain
[8] Hosp Santa Creu & Sant Pau, Serv Med Intens, Barcelona, Spain
[9] Hosp Univ Araba, Serv Med Intens, Vitoria, Alava, Spain