{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,24]],"date-time":"2026-10-24T01:58:29Z","timestamp":1792807109053,"version":"4.5.0"},"reference-count":25,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T00:00:00Z","timestamp":1768176000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003196","name":"Ministero della Salute","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100003196","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Med."],"abstract":"\n Background<\/jats:title>\n \n Efficient oxygen transport depends on hemoglobin (Hb) affinity for O\n 2<\/jats:sub>\n , which is modulated by factors like PCO\n 2<\/jats:sub>\n , as described by the Bohr effect. This\n in vitro<\/jats:italic>\n study explored how varying PO\n 2<\/jats:sub>\n and PCO\n 2<\/jats:sub>\n influence hemoglobin oxygen saturation (HbO\n 2<\/jats:sub>\n ) and plasma electrolyte concentrations in whole human blood.\n <\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n Blood from six healthy volunteers was equilibrated at 37\u00b0C with gas mixtures spanning PO\n 2<\/jats:sub>\n and PCO\n 2<\/jats:sub>\n ranges. A total of 346 samples were analyzed for blood gases, HbO\n 2<\/jats:sub>\n , and electrolytes. The HbO\n 2<\/jats:sub>\n dissociation curve was modeled using a Gompertz function within a non-linear mixed-effects framework, while electrolyte dynamics were assessed via polynomial models.\n <\/jats:p>\n <\/jats:sec>\n \n Results<\/jats:title>\n \n HbO\n 2<\/jats:sub>\n saturation ranged from 1.4 to 99.6%. Increasing PCO\n 2<\/jats:sub>\n shifted the dissociation curve rightward, steepening its slope and raising the inflection point\u2014hallmarks of the Bohr effect\u2014without affecting maximal HbO\n 2<\/jats:sub>\n . Electrolyte analysis revealed that chloride decreased with PCO\n 2<\/jats:sub>\n and increased with HbO\n 2<\/jats:sub>\n , consistent with the erythrocyte chloride shift. Sodium increased with PCO\n 2<\/jats:sub>\n , and a significant interaction between HbO\n 2<\/jats:sub>\n and PCO\n 2<\/jats:sub>\n was observed. Strong ion difference (SID) decreased linearly with HbO\n 2<\/jats:sub>\n and increased quadratically with PCO\n 2<\/jats:sub>\n , suggesting a compensatory role in CO\n 2<\/jats:sub>\n -induced acid-base changes.\n <\/jats:p>\n <\/jats:sec>\n \n Conclusion<\/jats:title>\n \n These findings, validated against external datasets, underscore the tight coupling between respiratory gas exchange and electrolyte homeostasis. The study provides novel insights into how CO\n 2<\/jats:sub>\n modulates both oxygen delivery and plasma ionic composition, with implications for understanding acid-base physiology and its regulation in health and disease.\n <\/jats:p>\n <\/jats:sec>","DOI":"10.3389\/fmed.2025.1708274","type":"journal-article","created":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T08:15:17Z","timestamp":1768205717000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":3,"title":["In vitro characterization of hemoglobin oxygen dissociation curves and electrolyte shifts in human blood under varying 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