{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T16:35:23Z","timestamp":1791477323485,"version":"4.3.4"},"reference-count":29,"publisher":"Public Library of Science (PLoS)","issue":"4","license":[{"start":{"date-parts":[[2022,4,26]],"date-time":"2022-04-26T00:00:00Z","timestamp":1650931200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Background<\/jats:title>\n<jats:p>Delaying intubation in patients who fail high-flow nasal cannula (HFNC) may result in increased mortality. The ROX index has been validated to predict HFNC failure among pneumonia patients with acute hypoxemic respiratory failure (AHRF), but little information is available for non-pneumonia causes. In this study, we validate the ROX index among AHRF patients due to both pneumonia or non-pneumonia causes, focusing on early prediction.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>This was a retrospective observational study in eight Singapore intensive care units from 1 January 2015 to 30 September 2017. All patients &gt;18 years who were treated with HFNC for AHRF were eligible and recruited. Clinical parameters and arterial blood gas values at HFNC initiation and one hour were recorded. HFNC failure was defined as requiring intubation post-HFNC initiation.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>HFNC was used in 483 patients with 185 (38.3%) failing HFNC. Among pneumonia patients, the ROX index was most discriminatory in pneumonia patients one hour after HFNC initiation [AUC 0.71 (95% CI 0.64\u20130.79)], with a threshold value of &lt;6.06 at one hour predicting HFNC failure (sensitivity 51%, specificity 80%, positive predictive value 61%, negative predictive value 73%). The discriminatory power remained moderate among pneumonia patients upon HFNC initiation [AUC 0.65 (95% CI 0.57\u20130.72)], non-pneumonia patients at HFNC initiation [AUC 0.62 (95% CI 0.55\u20130.69)] and one hour later [AUC 0.63 (95% CI 0.56\u20130.70)].<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusion<\/jats:title>\n<jats:p>The ROX index demonstrated moderate discriminatory power among patients with either pneumonia or non-pneumonia-related AHRF at HFNC initiation and one hour later.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0261234","type":"journal-article","created":{"date-parts":[[2022,4,26]],"date-time":"2022-04-26T17:31:15Z","timestamp":1650994275000},"page":"e0261234","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":13,"title":["Expanding the utility of the ROX index among patients with acute hypoxemic respiratory failure"],"prefix":"10.1371","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1516-3454","authenticated-orcid":true,"given":"Andrew","family":"Li","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3805-4680","authenticated-orcid":true,"given":"Matthew Edward","family":"Cove","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jason","family":"Phua","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ser Hon","family":"Puah","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vicky","family":"Ng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amit","family":"Kansal","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qiao Li","family":"Tan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juliet Tolentino","family":"Sahagun","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juvel","family":"Taculod","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Addy Yong-Hui","family":"Tan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amartya","family":"Mukhopadhyay","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chee Kiang","family":"Tay","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1822-9455","authenticated-orcid":true,"given":"Kollengode","family":"Ramanathan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yew Woon","family":"Chia","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Duu Wen","family":"Sewa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Meiying","family":"Chew","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sennen J. W.","family":"Lew","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shirley","family":"Goh","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shekhar","family":"Dhanvijay","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jonathan Jit-Ern","family":"Tan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kay Choong See","family":"FCCP","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"name":"on behalf of SICM-NICER Group","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2022,4,26]]},"reference":[{"key":"pone.0261234.ref001","doi-asserted-by":"crossref","first-page":"1128","DOI":"10.1164\/rccm.201701-0006ED","article-title":"Not Just Oxygen? Mechanisms of Benefit from High-Flow Nasal Cannula in Hypoxemic Respiratory Failure","volume":"195","author":"EC Goligher","year":"2017","journal-title":"Am J Respir Crit Care Med"},{"key":"pone.0261234.ref002","doi-asserted-by":"crossref","first-page":"1207","DOI":"10.1164\/rccm.201605-0916OC","article-title":"Physiologic Effects of High-Flow Nasal Cannula in Acute Hypoxemic Respiratory Failure","volume":"195","author":"T Mauri","year":"2017","journal-title":"Am J Respir Crit Care Med"},{"key":"pone.0261234.ref003","doi-asserted-by":"crossref","first-page":"2238","DOI":"10.1007\/s00134-020-06228-7","article-title":"Use of nasal high flow oxygen during acute respiratory failure","volume":"46","author":"JD Ricard","year":"2020","journal-title":"Intensive Care Med"},{"key":"pone.0261234.ref004","doi-asserted-by":"crossref","first-page":"162","DOI":"10.4187\/respcare.03423","article-title":"Use of high-flow nasal cannula oxygen therapy in subjects with ARDS: a 1-year observational study","volume":"60","author":"J Messika","year":"2015","journal-title":"Respir Care"},{"key":"pone.0261234.ref005","doi-asserted-by":"crossref","first-page":"1383","DOI":"10.4187\/respcare.04016","article-title":"High-flow nasal cannula in a mixed adult ICU","volume":"60","author":"KA Gaunt","year":"2015","journal-title":"Respir Care"},{"key":"pone.0261234.ref006","doi-asserted-by":"crossref","first-page":"2307","DOI":"10.2169\/internalmedicine.54.4266","article-title":"High-flow nasal cannula therapy for acute hypoxemic respiratory failure in adults: a retrospective analysis","volume":"54","author":"W Hyun Cho","year":"2015","journal-title":"Intern Med"},{"key":"pone.0261234.ref007","doi-asserted-by":"crossref","first-page":"2185","DOI":"10.1056\/NEJMoa1503326","article-title":"High-flow oxygen through nasal cannula in acute hypoxemic respiratory failure","volume":"372","author":"JP Frat","year":"2015","journal-title":"N Engl J Med"},{"key":"pone.0261234.ref008","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1097\/MAJ.0000000000000557","article-title":"High flow nasal cannulas for oxygenation: an audit of its use in a tertiary hospital","volume":"350","author":"D Sotello","year":"2015","journal-title":"Am J Med Sci"},{"key":"pone.0261234.ref009","doi-asserted-by":"crossref","first-page":"291","DOI":"10.4187\/respcare.04252","article-title":"Randomized controlled trial of humidified high-flow nasal oxygen for acute respiratory distress in the emergency department: the HOT-ER study","volume":"61","author":"PG Jones","year":"2016","journal-title":"Respir Care"},{"key":"pone.0261234.ref010","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1186\/1471-2253-14-66","article-title":"Nasal high-flow oxygen therapy in patients with hypoxic respiratory failure: effect on functional and subjective respiratory parameters compared to conventional oxygen therapy and non-invasive ventilation","volume":"14","author":"N Schwabbauer","year":"2014","journal-title":"BMC Anesthesiology"},{"key":"pone.0261234.ref011","doi-asserted-by":"crossref","first-page":"1780","DOI":"10.1007\/s00134-011-2354-6","article-title":"Beneficial effects of humidified high flow nasal oxygen in critical care patients: a prospective pilot study","volume":"37","author":"B Sztrymf","year":"2011","journal-title":"Intensive Care Med"},{"key":"pone.0261234.ref012","doi-asserted-by":"crossref","first-page":"1077","DOI":"10.2147\/COPD.S104616","article-title":"Nasal high flow improves ventilation in patients with COPD","volume":"11","author":"J Braunlich","year":"2016","journal-title":"Int J Chron Obstruct Pulmon Dis"},{"key":"pone.0261234.ref013","doi-asserted-by":"crossref","first-page":"759","DOI":"10.1136\/thoraxjnl-2015-207962","article-title":"Nasal high flow oxygen therapy in patients with COPD reduces respiratory rate and tissue carbon dioxide while increasing tidal and end-expiratory lung volumes: a randomised crossover trial","volume":"71","author":"JF Fraser","year":"2016","journal-title":"Thorax"},{"key":"pone.0261234.ref014","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1016\/j.annemergmed.2017.03.028","article-title":"High-flow nasal cannula versus conventional oxygen therapy in emergency department patients with cardiogenic pulmonary edema: a randomized controlled trial","volume":"70","author":"O Makdee","year":"2017","journal-title":"Ann Emerg Med"},{"key":"pone.0261234.ref015","doi-asserted-by":"crossref","first-page":"623","DOI":"10.1007\/s00134-015-3693-5","article-title":"Failure of high-flow nasal cannula may delay intubation and increase mortality","volume":"41","author":"BJ Kang","year":"2015","journal-title":"Intensive Care Med"},{"key":"pone.0261234.ref016","doi-asserted-by":"crossref","first-page":"200","DOI":"10.1016\/j.jcrc.2016.05.022","article-title":"Predicting success of high-flow nasal cannula in pneumonia patients with hypoxemic respiratory failure: the utility of the ROX index","volume":"35","author":"O Roca","year":"2016","journal-title":"J Crit Care"},{"key":"pone.0261234.ref017","doi-asserted-by":"crossref","first-page":"1368","DOI":"10.1164\/rccm.201803-0589OC","article-title":"An index combining respiratory rate and oxygenation to predict outcome of nasal high flow therapy","volume":"199","author":"O Roca","year":"2019","journal-title":"Am J Respir Crit Care Med"},{"key":"pone.0261234.ref018","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1186\/s40560-020-00458-z","article-title":"Early prediction of high flow nasal cannula therapy outcomes using a modified ROX index incorporating heart rate","volume":"8","author":"KJ Goh","year":"2020","journal-title":"Journal of Intensive Care"},{"key":"pone.0261234.ref019","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1186\/s13613-019-0578-8","article-title":"Predictors of successful separation from high-flow nasal oxygen therapy in patients with acute respiratory failure: a retrospective monocentre study","volume":"9","author":"M Rodriguez","year":"2019","journal-title":"Ann Intensive Care"},{"key":"pone.0261234.ref020","doi-asserted-by":"crossref","first-page":"2099","DOI":"10.1001\/jama.2018.14282","article-title":"Effect of high-flow nasal oxygen vs standard oxygen on 28-day mortality in immunocompromised patients with acute respiratory failure\u2014the HIGH randomized clinical trial","volume":"320","author":"E Azoulay","year":"2018","journal-title":"JAMA"},{"key":"pone.0261234.ref021","doi-asserted-by":"crossref","first-page":"788","DOI":"10.1001\/jama.2016.0291","article-title":"Epidemiology, patterns of care, and mortality for patients with acute respiratory distress syndrome in intensive care units in 50 countries","volume":"315","author":"G Bellani","year":"2016","journal-title":"JAMA"},{"key":"pone.0261234.ref022","doi-asserted-by":"crossref","first-page":"e274","DOI":"10.1097\/CCM.0000000000002085","article-title":"High-flow nasal cannula oxygenation in immunocompromised patients with acute hypoxemic respiratory failure: a Groupe de Recherche respiratoire en reanimation onco-hematologique study","volume":"45","author":"V Lemiale","year":"2017","journal-title":"Crit Care Med"},{"key":"pone.0261234.ref023","doi-asserted-by":"crossref","first-page":"646","DOI":"10.1016\/S2213-2600(16)30093-5","article-title":"Effect of non-invasive oxygenation strategies in immunocompromised patients with severe acute respiratory failure: a post-hoc analysis of a randomised trial","volume":"4","author":"JP Frat","year":"2016","journal-title":"Lancet Respir Med"},{"key":"pone.0261234.ref024","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1016\/S2213-2600(18)30345-X","article-title":"Acute respiratory failure in immunocompromised adults","volume":"7","author":"E Azoulay","year":"2019","journal-title":"Lancet Respir Med"},{"key":"pone.0261234.ref025","doi-asserted-by":"crossref","first-page":"1808","DOI":"10.1007\/s00134-017-4947-1","article-title":"Acute hypoxemic respiratory failure in immunocompromised patients; the Efraim multinational prospective cohort study","volume":"43","author":"E Azoulay","year":"2017","journal-title":"Intensive Care Med"},{"key":"pone.0261234.ref026","doi-asserted-by":"crossref","first-page":"1149","DOI":"10.1111\/resp.13050","article-title":"Physiological effects of titrated oxygen via nasal high-flow cannulae in COPD exacerbations: a randomized controlled cross-over trial","volume":"22","author":"J Pilcher","year":"2017","journal-title":"Respirology"},{"key":"pone.0261234.ref027","doi-asserted-by":"crossref","first-page":"1077","DOI":"10.2147\/COPD.S104616","article-title":"Nasal high-flow improves ventilation in patients with COPD","volume":"11","author":"J Braunlich","year":"2016","journal-title":"Int J COPD"},{"key":"pone.0261234.ref028","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1159\/000342027","article-title":"Effects of nasal high flow on ventilation in volunteers, COPD and idiopathic pulmonary fibrosis patients","volume":"85","author":"J Braunlich","year":"2013","journal-title":"Respiration"},{"key":"pone.0261234.ref029","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1186\/s13054-020-2828-4","article-title":"Safe patient transport for COVID-19","volume":"24","author":"MF Liew","year":"2020","journal-title":"Crit Care"}],"updated-by":[{"DOI":"10.1371\/journal.pone.0282136","type":"correction","label":"Correction","source":"publisher","updated":{"date-parts":[[2023,2,16]],"date-time":"2023-02-16T00:00:00Z","timestamp":1676505600000}}],"container-title":["PLOS ONE"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0261234","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,26]],"date-time":"2022-04-26T17:50:04Z","timestamp":1650995404000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0261234"}},"subtitle":[],"editor":[{"given":"Tai-Heng","family":"Chen","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2022,4,26]]},"references-count":29,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2022,4,26]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0261234","relation":{"correction":[{"id-type":"doi","id":"10.1371\/journal.pone.0282136","asserted-by":"object"}]},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,4,26]]}}}