{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T14:15:34Z","timestamp":1777990534719,"version":"3.51.4"},"reference-count":19,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T00:00:00Z","timestamp":1767744000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,5,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Bicarbonate concentration is widely used to assess acid-base disorders in patients, and the concentration can be directly measured or calculated. When discrepant results between measured bicarbonate (mHCO3\u2212) and calculated bicarbonate (cHCO3\u2212) are observed, it can lead to confusion among clinicians and potential for misdiagnosis. Here we assessed the agreement between cHCO3\u2212 from the Radiometer blood gas analyzer and mHCO3\u2212 from 3 different chemistry instruments.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Three institutions that measure bicarbonate using chemistry analyzers from 3 different manufacturers and derive bicarbonate on Radiometer blood gas analyzers participated in this study. De-identified patient data include plasma mHCO3\u2212 and blood gas cHCO3\u2212 results (arterial and venous) collected within +\/\u2212 20\u2005min. Correlations and biases were determined.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Deming regression analysis showed good correlations between cHCO3\u2212 and mHCO3\u2212. Bland\u2013Altman analysis revealed the greatest bias between Radiometer and Abbott Architect (\u22122.63\u2005mmol\/L), followed by Siemens Advia (0.49\u2005mmol\/L) and Beckman AU680 (\u22120.45\u2005mmol\/L).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>This is the first study to compare cHCO3\u2212 from the Radiometer blood gas analyzer against mHCO3\u2212 results from multiple chemistry analyzers. Our results suggest that the Radiometer blood gas analyzer, Siemens Advia, and Beckman AU680 agree well with each other. However, bicarbonate results may be negatively biased when measured on the Abbott Architect compared with the other methods.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/jalm\/jfaf201","type":"journal-article","created":{"date-parts":[[2025,12,10]],"date-time":"2025-12-10T13:08:58Z","timestamp":1765372138000},"page":"483-492","source":"Crossref","is-referenced-by-count":0,"title":["Assessment of Instrument-Specific Variation between Measured and Calculated Bicarbonate"],"prefix":"10.1093","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5658-133X","authenticated-orcid":false,"given":"Nga Yeung","family":"Tang","sequence":"first","affiliation":[{"name":"Department of Pathology, University of Illinois Chicago , Chicago, IL ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-8484-6798","authenticated-orcid":false,"given":"Carmen","family":"Gherasim","sequence":"additional","affiliation":[{"name":"Department of Pathology, University of Michigan , Ann Arbor, MI ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lee","family":"Schroeder","sequence":"additional","affiliation":[{"name":"Department of Pathology, University of Michigan , Ann Arbor, MI ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6964-5104","authenticated-orcid":false,"given":"Hsuan-Chieh","family":"Liao","sequence":"additional","affiliation":[{"name":"Departments of Laboratory Medicine and Pathology, University of Washington , Seattle, WA ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qian","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Corewell Health , Royal Oak, MI ,","place":["United States"]},{"name":"Department of Pathology and Laboratory Medicine, Oakland University William Beaumont School of Medicine , Auburn Hills, MI ,","place":["United States"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2026,1,7]]},"reference":[{"key":"2026050509533315800_jfaf201-B1","doi-asserted-by":"crossref","first-page":"2093","DOI":"10.1093\/clinchem\/36.12.2093","article-title":"Discordance between measured and calculated total carbon dioxide","volume":"36","author":"Ungerer","year":"1990","journal-title":"Clin Chem"},{"key":"2026050509533315800_jfaf201-B2","doi-asserted-by":"crossref","first-page":"1586","DOI":"10.1373\/clinchem.2008.107441","article-title":"Comparison of measured and 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