Villar, JesúsFernández, CristinaGonzález-Martín, Jesús MFerrando, CarlosAñón, José MDel Saz-Ortíz, Ana MDíaz-Lamas, AnaBueno-González, AnaFernández, LorenaDomínguez-Berrot, Ana MPeinado, EduardoAndaluz-Ojeda, DavidGonzález-Higueras, ElenaVidal, AnxelaFernández, M MarMora-Ordoñez, Juan MMurcia, IsabelTarancón, ConcepciónMerayo, EleuterioPérez, AlbaRomera, Miguel AAlba, FranciscoPestaña, DavidRodríguez-Suárez, PedroFernández, Rosa LSteyerberg, Ewout WBerra, LorenzoSlutsky, Arthur SThe Spanish Initiative For Epidemiology Stratification And Therapies Of Ards Siesta Network,2023-05-032023-05-032022-09-272077-0383http://hdl.handle.net/10668/21351Introduction: In patients with acute respiratory distress syndrome (ARDS), the PaO2/FiO2 ratio at the time of ARDS diagnosis is weakly associated with mortality. We hypothesized that setting a PaO2/FiO2 threshold in 150 mm Hg at 24 h from moderate/severe ARDS diagnosis would improve predictions of death in the intensive care unit (ICU). Methods: We conducted an ancillary study in 1303 patients with moderate to severe ARDS managed with lung-protective ventilation enrolled consecutively in four prospective multicenter cohorts in a network of ICUs. The first three cohorts were pooled (n = 1000) as a testing cohort; the fourth cohort (n = 303) served as a confirmatory cohort. Based on the thresholds for PaO2/FiO2 (150 mm Hg) and positive end-expiratory pressure (PEEP) (10 cm H2O), the patients were classified into four possible subsets at baseline and at 24 h using a standardized PEEP-FiO2 approach: (I) PaO2/FiO2 ≥ 150 at PEEPenAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/ARDS criterialung-protective ventilationmortalityoutcomepredictionstratificationresearch article36233592open access10.3390/jcm11195724PMC9570540https://www.mdpi.com/2077-0383/11/19/5724/pdf?version=1665298329https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9570540/pdf