{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T18:08:03Z","timestamp":1788890883826,"version":"build-2803163510"},"reference-count":46,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T00:00:00Z","timestamp":1788825600000},"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":"\n Introduction<\/jats:title>\n Acute carbon monoxide poisoning frequently induces complex acid-base disturbances; however, whether hypocapnia serves solely as a compensatory response to metabolic acidosis or involves additional factors remains insufficiently characterized.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n We retrospectively analyzed 940 emergency department patients with acute carbon monoxide poisoning (January 2019\u2013February 2025), stratified by base excess into an acidosis group (<\u22123 mmol\/L) and a non-acidosis group (\u2265 \u22123 mmol\/L). Group comparisons used Mann-Whitney U tests, Spearman\u2019s correlations assessed bivariate relationships, and hierarchical regression modeled PaCO\n 2<\/jats:sub>\n determinants.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n The acidosis group (\n n<\/jats:italic>\n \u2009=\u2009169) showed higher carboxyhemoglobin (26.5% vs. 21.6%) and lactate (4.4 vs. 1.7 mmol\/L), and lower pH (7.37 vs. 7.41) and PaCO\n 2<\/jats:sub>\n (33 vs. 39 mmHg) (all\n P<\/jats:italic>\n \u2009<\u20090.001). Base excess correlated positively with PaCO\n 2<\/jats:sub>\n (\n \u03c1<\/jats:italic>\n \u2009=\u20090.489) and pH (\n \u03c1<\/jats:italic>\n \u2009=\u20090.498), and negatively with lactate (\n \u03c1<\/jats:italic>\n \u2009=\u2009\u22120.414) (all\n P<\/jats:italic>\n \u2009<\u20090.001). Base excess was the strongest independent predictor of PaCO\n 2<\/jats:sub>\n (\n \u03b2<\/jats:italic>\n \u2009=\u20090.866), with each 1 mmol\/L decrease associated with a 1.57 mmHg reduction (95% CI: 1.47\u20131.68). These associations were more pronounced in acidotic patients (\n \u03b2<\/jats:italic>\n \u2009=\u20091.289 vs. 0.453) and males (\n \u03b2<\/jats:italic>\n \u2009=\u20091.106 vs. 0.750). Curve-fitting showed only a modest linear relationship (\n R<\/jats:italic>\n 2<\/jats:sup>\n \u2009=\u20090.211).\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n \n In acute carbon monoxide poisoning, metabolic acidosis is associated with hypocapnia, but the relationship is modest and context-dependent. The limited linear association between base excess and PaCO\n 2<\/jats:sub>\n , together with effect modification by acidosis status and sex, indicates hypocapnia involves factors beyond simple metabolic compensation.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.1371\/journal.pone.0356796","type":"journal-article","created":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T17:30:17Z","timestamp":1788888617000},"page":"e0356796","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Hypocapnia in acute carbon monoxide poisoning: A complex interaction beyond metabolic compensation"],"prefix":"10.1371","volume":"21","author":[{"given":"Yongai","family":"Ling","sequence":"first","affiliation":[{"name":"Health Promotion Center, People\u2019s Hospital of Anji","place":["Huzhou, Zhejiang, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xianwei","family":"Xiong","sequence":"additional","affiliation":[{"name":"People\u2019s Hospital of Anji","place":["Huzhou, Zhejiang, China"],"department":["Department of Emergency Medicine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Changsheng","family":"Ye","sequence":"additional","affiliation":[{"name":"People\u2019s Hospital of Anji","place":["Huzhou, Zhejiang, China"],"department":["Department of Emergency Medicine"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0008-7358-1324","authenticated-orcid":true,"given":"Weiguang","family":"Wang","sequence":"additional","affiliation":[{"name":"People\u2019s Hospital of Anji","place":["Huzhou, Zhejiang, China"],"department":["General Practice 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