{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T14:05:11Z","timestamp":1780322711795,"version":"3.54.1"},"reference-count":30,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T00:00:00Z","timestamp":1780272000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: To evaluate the prognostic value of end-tidal carbon dioxide (ETCO2), arterial carbon dioxide (PaCO2), their difference (\u0394CO2 = PaCO2\u2013ETCO2), and the ETCO2\/PaCO2 ratio for 30-day mortality in adult patients intubated for acute respiratory failure in the emergency department (ED). Materials and Methods: In this single-center, prospective observational study, we enrolled consecutive adults intubated in the ED who had at least two paired arterial blood gas and capnography measurements within 90 min post-intubation. PaCO2 and ETCO2 were recorded at 0, 30, 60, and 90 min, and \u0394CO2 and ETCO2\/PaCO2 were calculated at each time point. Between-group comparisons, repeated-measures analyses, and logistic regression were used to explore associations, and prognostic performance was assessed using receiver operating characteristic curves. Results: Among 100 patients (36% female); 30- and 90-day mortality were 64% and 70%, respectively. Non-survivors were older, had lower mean arterial pressure after intubation, higher inflammatory and coagulation markers, and more frequent pneumonia and pulmonary embolism. ETCO2 values were consistently lower in non-survivors at 0, 30, and 60 min, while PaCO2 was also lower at early time points. \u0394CO2 and the ETCO2\/PaCO2 ratio did not differ between survivors and non-survivors. Among all CO2 metrics and time points, only ETCO2 showed low-to-moderate discrimination for 30-day mortality (area under the curve 0.65\u20130.70). Conclusions: In ED patients emergently intubated for acute respiratory failure, absolute ETCO2 values in the early post-intubation period provide modest prognostic information for short-term mortality, whereas \u0394CO2 and ETCO2\/PaCO2 do not appear to add prognostic value beyond ETCO2 alone.<\/jats:p>","DOI":"10.3390\/medicina62061075","type":"journal-article","created":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T12:19:42Z","timestamp":1780316382000},"page":"1075","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Predictive Value of End-Tidal CO2, Arterial CO2, CO2 Gap and Ratio for 30-Day Mortality in Emergency Department Intubations: A Prospective Analysis"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8446-9898","authenticated-orcid":false,"given":"Melis","family":"Efeoglu Sacak","sequence":"first","affiliation":[{"name":"Department of Emergency Medicine, Marmara University School of Medicine, 34899 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2758-8214","authenticated-orcid":false,"given":"Emir","family":"Unal","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Marmara University School of Medicine, 34899 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ozgecan","family":"Gorman","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, King\u2019s College Hospital NHS Foundation Trust, London SE5 9RS, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2282-6896","authenticated-orcid":false,"given":"Aykut","family":"Ozkan","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Marmara University Pendik Training and Research Hospital, 34899 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4419-6135","authenticated-orcid":false,"given":"Nurseli","family":"Bayram","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Marmara University Pendik Training and Research Hospital, 34899 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0110-3533","authenticated-orcid":false,"given":"Ozge","family":"Onur","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Marmara University School of Medicine, 34899 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1316-0308","authenticated-orcid":false,"given":"Haldun","family":"Akoglu","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Marmara University School of Medicine, 34899 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4589-8251","authenticated-orcid":false,"given":"Arzu","family":"Denizbasi Altinok","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Marmara University School of Medicine, 34899 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1056\/NEJM198803103181005","article-title":"End-tidal carbon dioxide concentration during cardiopulmonary resuscitation","volume":"318","author":"Falk","year":"1989","journal-title":"N. 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