Fabiana MadottoTài PhamGiacomo BellaniLieuwe D. BosFabienne D. SimonisEddy FanAntonio ArtigasLaurent BrochardMarcus J. SchultzJohn G. LaffeyAntonio PesentiAndres EstebanLuciano GattinoniFrank van HarenAnders LarssonDaniel F. McAuleyMarco RanieriGordon RubenfeldB. Taylor ThompsonHermann WriggeArthur S. SlutskyFernando RiosFrank Van HarenT. SottiauxP. DepuydtFredy S. LoraLuciano Cesar AzevedoEddy FanGuillermo BugedoHaibo QiuMarcos GonzalezJuan SileskyVladimir CernyJonas NielsenManuel JibajaDimitrios MatamisJorge Luis RaneroPravin AminS. M. HashemianKevin ClarksonKiyoyasu KurahashiAsisclo VillagomezAmine Ali ZeggwaghLeo M. HeunksJon Henrik LaakeJose Emmanuel PaloAntero do Vale FernandesDorel SandescYaasen ArabiVesna BumbasierevicNicolas NinJose A. LorenteAnders LarssonLise PiquilloudFekri AbrougDaniel F. McAuleyLia McNameeJavier HurtadoEd BajwaGabriel DémpaireHektor SulaLordian NunciAlma CaniAlan ZazuChristian DelleraRisso V. AlejandroJulio DaldinMauricio VinzioRuben O. FernandezLuis P. CardonnetLisandro R. BettiniMariano Carboni BissoEmilio M. OsmanMariano G. SettenPablo LovazzanoJavier AlvarezVeronica VillarNorberto C. PozoNicolas GrubissichGustavo A. PlotnikowDaniela N. VasquezSantiago IlutovichNorberto TiribelliAriel ChenaCarlos A. PellegriniMaría G. SaenzElisa EstenssoroMatias BrizuelaHernan GianinettoPablo E. GomezValeria I. CerratoMarco G. BezziSilvina A. BorelloFlavia A. LoiaconoAdriana M. FernandezSerena KnowlesClaire ReynoldsDeborah M. InskipJennene J. MillerLi Ka Shing Knowledge InstituteUniversitat Autònoma de BarcelonaSaint Michael's Hospital University of TorontoUniversity of TorontoUniversity Health Network University of TorontoAzienda Ospedaliera San Gerardo MonzaMahidol UniversityUniversity of Milano - BicoccaNational University of Ireland GalwayAmsterdam UMC - University of Amsterdam2019-08-282019-08-282018-05-01Intensive Care Medicine. Vol.44, No.5 (2018), 564-57714321238034246422-s2.0-85045095335https://repository.li.mahidol.ac.th/handle/20.500.14594/46740© 2018, Springer-Verlag GmbH Germany, part of Springer Nature and ESICM. Purpose: To evaluate patients with resolved versus confirmed ARDS, identify subgroups with substantial mortality risk, and to determine the utility of day 2 ARDS reclassification. Methods: Our primary objective, in this secondary LUNG SAFE analysis, was to compare outcome in patients with resolved versus confirmed ARDS after 24 h. Secondary objectives included identifying factors associated with ARDS persistence and mortality, and the utility of day 2 ARDS reclassification. Results: Of 2377 patients fulfilling the ARDS definition on the first day of ARDS (day 1) and receiving invasive mechanical ventilation, 503 (24%) no longer fulfilled the ARDS definition the next day, 52% of whom initially had moderate or severe ARDS. Higher tidal volume on day 1 of ARDS was associated with confirmed ARDS [OR 1.07 (CI 1.01–1.13), P = 0.035]. Hospital mortality was 38% overall, ranging from 31% in resolved ARDS to 41% in confirmed ARDS, and 57% in confirmed severe ARDS at day 2. In both resolved and confirmed ARDS, age, non-respiratory SOFA score, lower PEEP and P/F ratio, higher peak pressure and respiratory rate were each associated with mortality. In confirmed ARDS, pH and the presence of immunosuppression or neoplasm were also associated with mortality. The increase in area under the receiver operating curve for ARDS reclassification on day 2 was marginal. Conclusions: ARDS, whether resolved or confirmed at day 2, has a high mortality rate. ARDS reclassification at day 2 has limited predictive value for mortality. The substantial mortality risk in severe confirmed ARDS suggests that complex interventions might best be tested in this population. Trial Registration: ClinicalTrials.gov NCT02010073.Mahidol UniversityMedicineArticleSCOPUS10.1007/s00134-018-5152-6