{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T20:17:18Z","timestamp":1780604238247,"version":"3.54.1"},"reference-count":26,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,1,8]],"date-time":"2021-01-08T00:00:00Z","timestamp":1610064000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Public Health"],"abstract":"<jats:p><jats:bold>Background:<\/jats:bold> Six months since the outbreak of coronavirus disease (COVID-19), the pandemic continues to grow worldwide, although the outbreak in Wuhan, the worst-hit area, has been controlled. Thus, based on the clinical experience in Wuhan, we hypothesized that there is a relationship between the patient's CO<jats:sub>2<\/jats:sub> levels and prognosis.<\/jats:p><jats:p><jats:bold>Methods:<\/jats:bold> COVID-19 patients' information was retrospectively collected from medical records at the Leishenshan Hospital, Wuhan. Logistic and Cox regression analyses were conducted to determine the correlation between decreased CO<jats:sub>2<\/jats:sub> levels and disease severity or mortality risk. The Kaplan-Meier curve analysis was coupled with the log-rank test to understand COVID-19 progression in patients with decreased CO<jats:sub>2<\/jats:sub> levels. Curve fitting was used to confirm the correlation between computed tomography scores and CO<jats:sub>2<\/jats:sub> levels.<\/jats:p><jats:p><jats:bold>Results:<\/jats:bold> Cox regression analysis showed that the mortality risk of COVID-19 patients correlated with decreased CO<jats:sub>2<\/jats:sub> levels. The adjusted hazard ratios for decreased CO<jats:sub>2<\/jats:sub> levels in COVID-19 patients were 8.710 [95% confidence interval (CI): 2.773\u201327.365, <jats:italic>P<\/jats:italic> &amp;lt; 0.001], and 4.754 (95% CI: 1.380\u201316.370, <jats:italic>P<\/jats:italic> = 0.013). The adjusted odds ratio was 0.950 (95% CI: 0.431\u20132.094, <jats:italic>P<\/jats:italic> = 0.900). The Kaplan-Meier survival curves demonstrated that patients with decreased CO<jats:sub>2<\/jats:sub> levels had a higher risk of mortality.<\/jats:p><jats:p><jats:bold>Conclusions:<\/jats:bold> Decreased CO<jats:sub>2<\/jats:sub> levels increased the mortality risk of COVID-19 patients, which might be caused by hyperventilation during mechanical ventilation. This finding provides important insights for clinical treatment recommendations.<\/jats:p>","DOI":"10.3389\/fpubh.2020.596168","type":"journal-article","created":{"date-parts":[[2021,1,8]],"date-time":"2021-01-08T17:15:52Z","timestamp":1610126152000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":6,"title":["Decreased CO2 Levels as Indicators of Possible Mechanical Ventilation-Induced Hyperventilation in COVID-19 Patients: A Retrospective Analysis"],"prefix":"10.3389","volume":"8","author":[{"given":"Di","family":"Hu","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinpeng","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rongfen","family":"Gao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shipei","family":"Wang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qianqian","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sichao","family":"Chen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianglong","family":"Huang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yihui","family":"Huang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Man","family":"Li","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Long","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zeming","family":"Liu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liang","family":"Guo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaohui","family":"Wu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2021,1,8]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"497","DOI":"10.1016\/S0140-6736(20)30183-5","article-title":"Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China","volume":"395","author":"Huang","year":"2020","journal-title":"Lancet."},{"key":"B2","doi-asserted-by":"publisher","first-page":"709","DOI":"10.1001\/jama.2020.1097","article-title":"The novel coronavirus originating in Wuhan, China: challenges for Global Health Governance","volume":"323","author":"Phelan","year":"2020","journal-title":"JAMA"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1101\/2020.02.07.937862","article-title":"Severe acute respiratory syndrome-related coronavirus: the species and its viruses \u2013 a statement of the Coronavirus Study Group","author":"Gorbalenya","year":"2020","journal-title":"bioRxiv."},{"key":"B4","doi-asserted-by":"publisher","first-page":"1054","DOI":"10.1016\/S0140-6736(20)30566-3","article-title":"Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study","volume":"395","author":"Zhou","year":"2020","journal-title":"Lancet."},{"key":"B5","unstructured":"Worldometer COVID-19 Data"},{"key":"B6","doi-asserted-by":"publisher","first-page":"1708","DOI":"10.1056\/NEJMoa2002032","article-title":"Clinical characteristics of coronavirus disease 2019 in China","volume":"382","author":"Guan","year":"2020","journal-title":"N Engl J Med."},{"key":"B7","doi-asserted-by":"publisher","first-page":"1199","DOI":"10.1056\/NEJMoa2001316","article-title":"Early transmission dynamics in Wuhan, China, of novel coronavirus-infected pneumonia","volume":"382","author":"Li","year":"2020","journal-title":"N Engl J Med."},{"key":"B8","doi-asserted-by":"publisher","first-page":"401","DOI":"10.1002\/jmv.25678","article-title":"Outbreak of pneumonia of unknown etiology in Wuhan, China: the mystery and the miracle","volume":"92","author":"Lu","year":"2020","journal-title":"J Med Virol."},{"key":"B9","doi-asserted-by":"publisher","first-page":"411","DOI":"10.3760\/cma.j.cn112151-20200312-00193","article-title":"A pathological report of three COVID-19 cases by minimal invasive autopsies","volume":"49","author":"Yao","year":"2020","journal-title":"Zhonghua Bing Li Xue Za Zhi."},{"key":"B10","doi-asserted-by":"publisher","first-page":"389","DOI":"10.1002\/hep.31301","article-title":"Longitudinal association between markers of liver injury and mortality in COVID-19 in China","volume":"72","author":"Lei","year":"2020","journal-title":"Hepatology"},{"key":"B11","doi-asserted-by":"publisher","first-page":"e5","DOI":"10.22037\/emergency.v6i1.19298","article-title":"Applications of End-Tidal Carbon Dioxide (ETCO2) monitoring in emergency department; a narrative review","volume":"6","author":"Aminiahidashti","year":"2018","journal-title":"Emerg."},{"key":"B12","doi-asserted-by":"publisher","first-page":"1061","DOI":"10.1001\/jama.2020.1585","article-title":"Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus-infected pneumonia in Wuhan, China","volume":"323","author":"Wang","year":"2020","journal-title":"JAMA"},{"key":"B13","doi-asserted-by":"publisher","first-page":"700","DOI":"10.1016\/j.jtho.2020.02.010","article-title":"Pulmonary pathology of early-phase 2019 novel coronavirus (COVID-19) pneumonia in two patients with lung cancer","volume":"15","author":"Tian","year":"2020","journal-title":"J Thorac Oncol."},{"key":"B14","doi-asserted-by":"publisher","first-page":"475","DOI":"10.1016\/S2213-2600(20)30079-5","article-title":"Clinical course and outcomes of critically ill patients with SARS-CoV-2 pneumonia in Wuhan, China: a single-centered, retrospective, observational study","volume":"8","author":"Yang","year":"2020","journal-title":"Lancet Respir Med."},{"key":"B15","doi-asserted-by":"publisher","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":"Bellani","year":"2016","journal-title":"JAMA."},{"key":"B16","doi-asserted-by":"publisher","first-page":"493","DOI":"10.1097\/01.pec.0000173345.07530.c0","article-title":"Capnography as a rapid assessment and triage tool for chemical terrorism","volume":"21","author":"Krauss","year":"2005","journal-title":"Pediatr Emerg Care."},{"key":"B17","doi-asserted-by":"publisher","first-page":"14","DOI":"10.1016\/j.jopan.2013.07.009","article-title":"Capnography (ETCO2), respiratory depression, and nursing interventions in moderately sedated adults undergoing transesophageal echocardiography (TEE)","volume":"30","author":"Adams","year":"2015","journal-title":"J Perianesth Nurs."},{"key":"B18","doi-asserted-by":"publisher","first-page":"500","DOI":"10.1197\/j.aem.2005.12.017","article-title":"Does end-tidal carbon dioxide monitoring detect respiratory events prior to current sedation monitoring practices?","volume":"13","author":"Burton","year":"2006","journal-title":"Acad Emerg Med."},{"key":"B19","doi-asserted-by":"publisher","first-page":"258","DOI":"10.1016\/j.annemergmed.2009.07.030","article-title":"Does end tidal CO2 monitoring during emergency department procedural sedation and analgesia with propofol decrease the incidence of hypoxic events? A randomized, controlled trial","volume":"55","author":"Deitch","year":"2010","journal-title":"Ann Emerg Med."},{"key":"B20","doi-asserted-by":"publisher","first-page":"379","DOI":"10.1213\/01.ANE.0000131964.67524.E7","article-title":"Capnography accurately detects apnea during monitored anesthesia care","volume":"99","author":"Soto","year":"2004","journal-title":"Anesth Analg."},{"key":"B21","doi-asserted-by":"publisher","first-page":"1281","DOI":"10.1056\/NEJMoa012835","article-title":"Pulmonary dead-space fraction as a risk factor for death in the acute respiratory distress syndrome","volume":"346","author":"Nuckton","year":"2002","journal-title":"N Engl J Med."},{"key":"B22","doi-asserted-by":"publisher","first-page":"1289","DOI":"10.1097\/CCM.0000000000004447","article-title":"Extracorporeal membrane oxygenation for coronavirus disease 2019-induced acute respiratory distress syndrome: a multicenter descriptive study","volume":"48","author":"Yang","year":"2020","journal-title":"Crit Care Med"},{"key":"B23","doi-asserted-by":"publisher","first-page":"1154","DOI":"10.1053\/j.jvca.2017.09.031","article-title":"Single-center experience with venovenous ECMO for influenza-related ARDS","volume":"32","author":"Buchner","year":"2018","journal-title":"J Cardiothorac Vasc Anesth."},{"key":"B24","doi-asserted-by":"publisher","first-page":"130","DOI":"10.1093\/eurjhf\/hfn013","article-title":"Heart failure and chronic obstructive pulmonary disease: diagnostic pitfalls and epidemiology","volume":"11","author":"Hawkins","year":"2009","journal-title":"Eur J Heart Fail."},{"key":"B25","doi-asserted-by":"publisher","first-page":"207","DOI":"10.1186\/cc696","article-title":"Carbon dioxide kinetics and capnography during critical care","volume":"4","author":"Anderson","year":"2000","journal-title":"Crit Care."},{"key":"B26","unstructured":"Chinese Clinical Guidance for COVID-19 Pneumonia Diagnosis and Treatment"}],"container-title":["Frontiers in Public Health"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpubh.2020.596168\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,1,14]],"date-time":"2021-01-14T03:00:25Z","timestamp":1610593225000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fpubh.2020.596168\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,1,8]]},"references-count":26,"alternative-id":["10.3389\/fpubh.2020.596168"],"URL":"https:\/\/doi.org\/10.3389\/fpubh.2020.596168","relation":{},"ISSN":["2296-2565"],"issn-type":[{"value":"2296-2565","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,1,8]]},"article-number":"596168"}}