{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T02:48:50Z","timestamp":1792205330022,"version":"4.4.0"},"reference-count":40,"publisher":"BMJ","issue":"1","license":[{"start":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T00:00:00Z","timestamp":1710288000000},"content-version":"unspecified","delay-in-days":12,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"DOI":"10.13039\/100001003","name":"Boehringer Ingelheim","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100001003","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open Resp Res"],"accepted":{"date-parts":[[2024,2,28]]},"published-print":{"date-parts":[[2024,3]]},"abstract":"<jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Fibrotic interstitial lung disease (ILD) is frequently associated with abnormal oxygenation; however, little is known about the accuracy of oxygen saturation by pulse oximetry (SpO<jats:sub>2<\/jats:sub>) compared with arterial blood gas (ABG) saturation (SaO<jats:sub>2<\/jats:sub>), the factors that influence the partial pressure of carbon dioxide (PaCO<jats:sub>2<\/jats:sub>) and the impact of PaCO<jats:sub>2<\/jats:sub> on outcomes in patients with fibrotic ILD.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Study design and methods<\/jats:title>\n                  <jats:p>Patients with fibrotic ILD enrolled in a large prospective registry with a room air ABG were included. Prespecified analyses included testing the correlation between SaO<jats:sub>2<\/jats:sub> and SpO<jats:sub>2<\/jats:sub>, the difference between SaO<jats:sub>2<\/jats:sub> and SpO<jats:sub>2<\/jats:sub>, the association of baseline characteristics with both the difference between SaO<jats:sub>2<\/jats:sub> and SpO<jats:sub>2<\/jats:sub> and the PaCO<jats:sub>2<\/jats:sub>, the association of baseline characteristics with acid-base category, and the association of PaCO<jats:sub>2<\/jats:sub> and acid-base category with time to death or transplant.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>A total of 532 patients with fibrotic ILD were included. Mean resting SaO<jats:sub>2<\/jats:sub> was 92\u00b14% and SpO<jats:sub>2<\/jats:sub> was 95\u00b13%. Mean PaCO<jats:sub>2<\/jats:sub> was 38\u00b16 mmHg, with 135 patients having PaCO<jats:sub>2<\/jats:sub> &lt;35 mmHg and 62 having PaCO<jats:sub>2<\/jats:sub> &gt;45 mmHg. Correlation between SaO<jats:sub>2<\/jats:sub> and SpO<jats:sub>2<\/jats:sub> was mild to moderate (r=0.39), with SpO<jats:sub>2<\/jats:sub> on average 3.0% higher than SaO<jats:sub>2<\/jats:sub>. No baseline characteristics were associated with the difference in SaO<jats:sub>2<\/jats:sub> and SpO<jats:sub>2<\/jats:sub>. Variables associated with either elevated or abnormal (elevated or low) PaCO<jats:sub>2<\/jats:sub> included higher smoking pack-years and lower baseline forced vital capacity (FVC). Lower baseline lung function was associated with an increased risk of chronic respiratory acidosis. PaCO<jats:sub>2<\/jats:sub> and acid-base status were not associated with time to death or transplant.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Interpretation<\/jats:title>\n                  <jats:p>SaO<jats:sub>2<\/jats:sub> and SpO<jats:sub>2<\/jats:sub> are weakly-to-moderately correlated in fibrotic ILD, with limited ability to accurately predict this difference. Abnormal PaCO<jats:sub>2<\/jats:sub> was associated with baseline FVC but was not associated with outcomes.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1136\/bmjresp-2023-002250","type":"journal-article","created":{"date-parts":[[2024,3,13]],"date-time":"2024-03-13T14:16:20Z","timestamp":1710339380000},"page":"e002250","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":3,"title":["Characteristics of pulse oximetry and arterial blood gas in patients with fibrotic interstitial lung disease"],"prefix":"10.1136","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-9714-5813","authenticated-orcid":false,"given":"Mira A","family":"Donaldson","sequence":"first","affiliation":[{"name":"Department of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kathryn","family":"Donohoe","sequence":"additional","affiliation":[{"name":"College of Medicine, University of Cincinnati, Cincinnati, Ohio, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deborah","family":"Assayag","sequence":"additional","affiliation":[{"name":"Department of Medicine, McGill University, Montreal, Qu\u00e9bec, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Celine","family":"Durand","sequence":"additional","affiliation":[{"name":"D\u00e9partement de M\u00e9decine, Centre de Recherche du Centre Hospitalier de l'Universite de Montreal, Montreal, Qu\u00e9bec, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jolene H","family":"Fisher","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Toronto, Toronto, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kerri","family":"Johannson","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Calgary, Calgary, Alberta, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin","family":"Kolb","sequence":"additional","affiliation":[{"name":"Department of Medicine, McMaster University, Hamilton, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stacey D","family":"Lok","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"H\u00e9l\u00e8ne","family":"Manganas","sequence":"additional","affiliation":[{"name":"D\u00e9partement de M\u00e9decine, Centre de Recherche du Centre Hospitalier de l'Universite de Montreal, Montreal, Qu\u00e9bec, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5890-3227","authenticated-orcid":false,"given":"Veronica","family":"Marcoux","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bohyung","family":"Min","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Calgary, Calgary, Alberta, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julie","family":"Morisset","sequence":"additional","affiliation":[{"name":"D\u00e9partement de M\u00e9decine, Centre de Recherche du Centre Hospitalier de l'Universite de Montreal, Montreal, Qu\u00e9bec, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel-Costin","family":"Marinescu","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada"},{"name":"Centre for Heart Lung Innovation, University of British Columbia, Vancouver, British Columbia, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher J","family":"Ryerson","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of British Columbia, Vancouver, British Columbia, Canada"},{"name":"Centre for Heart Lung Innovation, University of British Columbia, Vancouver, British Columbia, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2024,3,13]]},"reference":[{"key":"2025083112410330000_11.1.e002250.1","doi-asserted-by":"crossref","first-page":"994","DOI":"10.1016\/j.chest.2021.04.037","article-title":"Incidence and prognostic significance of hypoxemia in fibrotic interstitial lung disease: an international cohort study","volume":"160","author":"Khor","year":"2021","journal-title":"Chest"},{"key":"2025083112410330000_11.1.e002250.2","doi-asserted-by":"publisher","DOI":"10.1016\/S0147-9563(98)90086-3"},{"key":"2025083112410330000_11.1.e002250.3","first-page":"194","article-title":"Limitations of pulse oximetry","volume":"39","author":"Mardirossian","year":"1992","journal-title":"Anesth Prog"},{"key":"2025083112410330000_11.1.e002250.4","doi-asserted-by":"publisher","DOI":"10.1177\/0310057X1804600307"},{"key":"2025083112410330000_11.1.e002250.5","doi-asserted-by":"publisher","DOI":"10.1378\/chest.109.5.1151"},{"key":"2025083112410330000_11.1.e002250.6","doi-asserted-by":"publisher","DOI":"10.1378\/chest.99.4.842"},{"key":"2025083112410330000_11.1.e002250.7","doi-asserted-by":"crossref","DOI":"10.1371\/journal.pone.0126979","article-title":"Accuracy of pulse oximeters in detecting hypoxemia in patients with chronic thromboembolic pulmonary hypertension","volume":"10","author":"Kohyama","year":"2015","journal-title":"PLoS One"},{"key":"2025083112410330000_11.1.e002250.8","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1155\/2016\/3562923","article-title":"The Canadian Registry for Pulmonary Fibrosis: design and rationale of a national pulmonary fibrosis registry","volume":"2016","author":"Ryerson","year":"2016","journal-title":"Canadian Respiratory Journal"},{"key":"2025083112410330000_11.1.e002250.9","doi-asserted-by":"crossref","DOI":"10.1186\/s12890-019-0986-4","article-title":"Baseline characteristics and comorbidities in the Canadian Registry for Pulmonary Fibrosis","volume":"19","author":"Fisher","year":"2019","journal-title":"BMC Pulm Med"},{"key":"2025083112410330000_11.1.e002250.10","unstructured":"Castro D , Patil SM , Keenaghan M . Arterial Blood Gas. Treasure Island (FL): StatPearls Publishing, 2019."},{"key":"2025083112410330000_11.1.e002250.11","doi-asserted-by":"publisher","DOI":"10.1164\/rccm.201908-1590ST"},{"key":"2025083112410330000_11.1.e002250.12","doi-asserted-by":"crossref","DOI":"10.1183\/13993003.00016-2016","article-title":"ERS\/ATS standards for single-breath carbon monoxide uptake in the lung","volume":"49","author":"Graham","year":"2017","journal-title":"Eur Respir J"},{"key":"2025083112410330000_11.1.e002250.13","doi-asserted-by":"crossref","DOI":"10.1038\/s41598-021-02634-z","article-title":"Impact of COVID-19 on the association between pulse oximetry and arterial oxygenation in patients with acute respiratory distress syndrome","volume":"12","author":"Nguyen","year":"2022","journal-title":"Sci Rep"},{"key":"2025083112410330000_11.1.e002250.14","doi-asserted-by":"crossref","first-page":"959","DOI":"10.1007\/s10439-020-02722-7","article-title":"An evolving clinical need: discordant oxygenation measurements of intubated COVID-19 patients","volume":"49","author":"Rubano","year":"2021","journal-title":"Ann Biomed Eng"},{"key":"2025083112410330000_11.1.e002250.15","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1111\/anae.15228","article-title":"Discrepancy between SPO2 and SAO2 in patients with Covid\u201019","volume":"76","author":"Wilson\u2010Baig","year":"2021","journal-title":"Anaesthesia"},{"key":"2025083112410330000_11.1.e002250.16","doi-asserted-by":"crossref","DOI":"10.3389\/fimmu.2021.687397","article-title":"Commonalities between ARDS, pulmonary fibrosis and COVID-19: the potential of autotaxin as a therapeutic target","volume":"12","author":"Ntatsoulis","year":"2021","journal-title":"Front Immunol"},{"key":"2025083112410330000_11.1.e002250.17","doi-asserted-by":"publisher","DOI":"10.1097\/00000542-200504000-00004"},{"key":"2025083112410330000_11.1.e002250.18","doi-asserted-by":"publisher","DOI":"10.1378\/chest.97.4.814"},{"key":"2025083112410330000_11.1.e002250.19","first-page":"594","article-title":"Accuracy of pulse oximetry in pigmented patients","volume":"86","author":"Bothma","year":"1996","journal-title":"S Afr Med J"},{"key":"2025083112410330000_11.1.e002250.20","doi-asserted-by":"publisher","DOI":"10.1213\/01.ane.0000285988.35174.d9"},{"key":"2025083112410330000_11.1.e002250.21","unstructured":"Menezes B , Sanchez-Martinez J , Fletcher L , et al . Use of pulse oximetry to select who should be screened for long term oxygen therapy (LTOT) in interstitial lung disease (ILD) patients. Eur Respir J 2014;44."},{"key":"2025083112410330000_11.1.e002250.22","doi-asserted-by":"crossref","DOI":"10.1186\/s12931-017-0621-y","article-title":"Health related quality of life in patients with idiopathic pulmonary fibrosis in clinical practice: Insights-IPF Registry","volume":"18","author":"Kreuter","year":"2017","journal-title":"Respir Res"},{"key":"2025083112410330000_11.1.e002250.23","doi-asserted-by":"crossref","unstructured":"Tzouvelekis A , Kourtidou S , Bouros E , et al . Impact of depression on patients with idiopathic pulmonary fibrosis. ERS International Congress 2017 abstracts; September 2017 doi:10.1183\/1393003.congress-2017.PA357","DOI":"10.1183\/1393003.congress-2017.PA357"},{"key":"2025083112410330000_11.1.e002250.24","doi-asserted-by":"publisher","DOI":"10.1136\/thx.47.2.93"},{"key":"2025083112410330000_11.1.e002250.25","doi-asserted-by":"crossref","DOI":"10.1155\/2022\/4205079","article-title":"The relationship of partial pressure of carbon dioxide (PaCO2) with disease severity indicators such as BODE and GOLD in hospitalized COPD patients","volume":"2022","author":"Zhang","year":"2022","journal-title":"Int J Clin Pract"},{"key":"2025083112410330000_11.1.e002250.26","first-page":"41","article-title":"Relationship between FEV1 and PaO2, PaCO2 in patients with chronic bronchitis","volume":"3","author":"Fard","year":"2004","journal-title":"Tanaffos"},{"key":"2025083112410330000_11.1.e002250.27","article-title":"Development and relevance of hypercapnia in COPD","volume":"2021","author":"Dave","year":"2021","journal-title":"Can Respir J"},{"key":"2025083112410330000_11.1.e002250.28","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00085.2009"},{"key":"2025083112410330000_11.1.e002250.29","doi-asserted-by":"publisher","DOI":"10.1111\/j.1752-699X.2011.00248.x"},{"key":"2025083112410330000_11.1.e002250.30","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.86.1.12"},{"key":"2025083112410330000_11.1.e002250.31","doi-asserted-by":"publisher","DOI":"10.1136\/thx.47.1.34"},{"key":"2025083112410330000_11.1.e002250.32","doi-asserted-by":"publisher","DOI":"10.1378\/chest.117.1.169"},{"key":"2025083112410330000_11.1.e002250.33","doi-asserted-by":"publisher","DOI":"10.1001\/jama.1971.03190110023006"},{"key":"2025083112410330000_11.1.e002250.34","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(80)91008-9"},{"key":"2025083112410330000_11.1.e002250.35","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(00)02323-0"},{"key":"2025083112410330000_11.1.e002250.36","doi-asserted-by":"publisher","DOI":"10.1159\/000086183"},{"key":"2025083112410330000_11.1.e002250.37","doi-asserted-by":"publisher","DOI":"10.1378\/chest.06-2124"},{"key":"2025083112410330000_11.1.e002250.38","doi-asserted-by":"publisher","DOI":"10.1159\/000131707"},{"key":"2025083112410330000_11.1.e002250.39","doi-asserted-by":"publisher","DOI":"10.1111\/j.1600-6143.2006.01276.x"},{"key":"2025083112410330000_11.1.e002250.40","doi-asserted-by":"crossref","DOI":"10.1183\/13993003.00404-2023","article-title":"Treatable traits: a comprehensive precision medicine approach in interstitial lung disease","volume":"62","author":"Khor","year":"2023","journal-title":"Eur Respir J"}],"container-title":["BMJ Open Respiratory Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bmjresp-2023-002250","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,8,31]],"date-time":"2025-08-31T19:41:13Z","timestamp":1756669273000},"score":1,"resource":{"primary":{"URL":"https:\/\/bmjopenrespres.bmj.com\/lookup\/doi\/10.1136\/bmjresp-2023-002250"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,3]]},"references-count":40,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2024,3,13]]},"published-print":{"date-parts":[[2024,3]]}},"alternative-id":["10.1136\/bmjresp-2023-002250"],"URL":"https:\/\/doi.org\/10.1136\/bmjresp-2023-002250","relation":{},"ISSN":["2052-4439"],"issn-type":[{"value":"2052-4439","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,3]]}}}