{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,30]],"date-time":"2026-10-30T22:37:13Z","timestamp":1793399833496,"version":"4.5.0"},"reference-count":27,"publisher":"Oxford University Press (OUP)","issue":"11","license":[{"start":{"date-parts":[[2019,6,1]],"date-time":"2019-06-01T00:00:00Z","timestamp":1559347200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2019,6,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Rationale<\/jats:title>\n                    <jats:p>One important concern during high-flow nasal cannula (HFNC) therapy in patients with acute hypoxemic respiratory failure is to not delay intubation.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>To validate the diagnostic accuracy of an index (termed ROX and defined as the ratio of oxygen saturation as measured by pulse oximetry\/FiO2 to respiratory rate) for determining HFNC outcome (need or not for intubation).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This was a 2-year multicenter prospective observational cohort study including patients with pneumonia treated with HFNC. Identification was through Cox proportional hazards modeling of ROX association with HFNC outcome. The most specific cutoff of the ROX index to predict HFNC failure and success was assessed.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Measurements and Main Results<\/jats:title>\n                    <jats:p>Among the 191 patients treated with HFNC in the validation cohort, 68 (35.6%) required intubation. The prediction accuracy of the ROX index increased over time (area under the receiver operating characteristic curve: 2 h, 0.679; 6 h, 0.703; 12 h, 0.759). ROX greater than or equal to 4.88 measured at 2 (hazard ratio, 0.434; 95% confidence interval, 0.264\u20130.715; P\u2009=\u20090.001), 6 (hazard ratio, 0.304; 95% confidence interval, 0.182\u20130.509; P\u2009&amp;lt;\u20090.001), or 12 hours (hazard ratio, 0.291; 95% confidence interval, 0.161\u20130.524; P\u2009&amp;lt;\u20090.001) after HFNC initiation was consistently associated with a lower risk for intubation. A ROX less than 2.85, less than 3.47, and less than 3.85 at 2, 6, and 12 hours of HFNC initiation, respectively, were predictors of HFNC failure. Patients who failed presented a lower increase in the values of the ROX index over the 12 hours. Among components of the index, oxygen saturation as measured by pulse oximetry\/FiO2 had a greater weight than respiratory rate.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In patients with pneumonia with acute respiratory failure treated with HFNC, ROX is an index that can help identify those patients with low and those with high risk for intubation.<\/jats:p>\n                    <jats:p>Clinical trial registered with www.clinicaltrials.gov (NCT 02845128).<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1164\/rccm.201803-0589oc","type":"journal-article","created":{"date-parts":[[2018,12,21]],"date-time":"2018-12-21T16:06:12Z","timestamp":1545408372000},"page":"1368-1376","source":"Crossref","is-referenced-by-count":664,"title":["An Index Combining Respiratory Rate and Oxygenation to Predict Outcome of Nasal High-Flow Therapy"],"prefix":"10.1093","volume":"199","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3841-4551","authenticated-orcid":false,"given":"Oriol","family":"Roca","sequence":"first","affiliation":[{"name":"Critical Care Department, Vall d\u2019Hebron University Hospital, Vall d\u2019Hebron Research Institute and"},{"name":"Ciber Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1224-4761","authenticated-orcid":false,"given":"Berta","family":"Caralt","sequence":"additional","affiliation":[{"name":"Critical Care Department, Vall d\u2019Hebron University Hospital, Vall d\u2019Hebron Research Institute and"},{"name":"Departament de Medicina, Universitat Aut\u00f2noma de Barcelona, Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2123-3527","authenticated-orcid":false,"given":"Jonathan","family":"Messika","sequence":"additional","affiliation":[{"name":"Service de R\u00e9animation M\u00e9dico-Chirurgicale, H\u00f4pital Louis Mourier, Assistance Publique\u2013H\u00f4pitaux de Paris (AP-HP), Colombes, France"},{"name":"INSERM, Infection Antimicrobials Modelling Evolution (IAME), Unit\u00e9 Mixte de Recherche (UMR) 1137, Paris, France"},{"name":"Universit\u00e9 Paris Diderot, IAME, UMR 1137, Sorbonne Paris Cit\u00e9, Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manuel","family":"Samper","sequence":"additional","affiliation":[{"name":"Critical Care Department, Hospital del Mar, Mar Research Institute, Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benjamin","family":"Sztrymf","sequence":"additional","affiliation":[{"name":"Service de R\u00e9animation Polyvalente et Surveillance Continue, H\u00f4pital Antoine B\u00e9cl\u00e8re, AP-HP, Clamart, France"},{"name":"INSERM U999: Pulmonary Hypertension, Physiopathologie et Innovation Th\u00e9rapeutique, H\u00f4pital Marie Lannelongue, Le Plessis Robinson, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gonzalo","family":"Hern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Critical Care Department, Virgen de la Salud University Hospital, Toledo, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2353-9968","authenticated-orcid":false,"given":"Marina","family":"Garc\u00eda-de-Acilu","sequence":"additional","affiliation":[{"name":"Critical Care Department, Vall d\u2019Hebron University Hospital, Vall d\u2019Hebron Research Institute and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean-Pierre","family":"Frat","sequence":"additional","affiliation":[{"name":"R\u00e9animation M\u00e9dicale, Centre Hospitalier Universitaire de Poitiers, Poitiers, France"},{"name":"Facult\u00e9 de M\u00e9decine et de Pharmacie de Poitiers, Universit\u00e9 de Poitiers, Poitiers, France; and"},{"name":"INSERM, Centre d\u2019Investigation Clinique-1402, Equipe 5 Acute Lung Injury and Ventilatory Support, Poitiers, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0809-6823","authenticated-orcid":false,"given":"Joan R.","family":"Masclans","sequence":"additional","affiliation":[{"name":"Ciber Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain"},{"name":"Departament de Medicina, Universitat Aut\u00f2noma de Barcelona, Barcelona, Spain"},{"name":"Critical Care Department, Hospital del Mar, Mar Research Institute, Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1828-2299","authenticated-orcid":false,"given":"Jean-Damien","family":"Ricard","sequence":"additional","affiliation":[{"name":"Service de R\u00e9animation M\u00e9dico-Chirurgicale, H\u00f4pital Louis Mourier, Assistance Publique\u2013H\u00f4pitaux de Paris (AP-HP), Colombes, France"},{"name":"INSERM, Infection Antimicrobials Modelling Evolution (IAME), Unit\u00e9 Mixte de Recherche (UMR) 1137, Paris, France"},{"name":"Universit\u00e9 Paris Diderot, IAME, UMR 1137, Sorbonne Paris Cit\u00e9, Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2019,6,1]]},"reference":[{"key":"2026030321284138200_bib1","doi-asserted-by":"crossref","first-page":"1128","DOI":"10.1164\/rccm.201701-0006ED","article-title":"Not just oxygen? 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