{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T04:54:56Z","timestamp":1781499296034,"version":"3.54.1"},"reference-count":33,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T00:00:00Z","timestamp":1781481600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100009088","name":"Veterin\u00e4rmedizinische Universit\u00e4t Wien","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100009088","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>\n                    Hypertonic saline (HS) has been used to enhance electrical impedance tomography (EIT) cardiac-related signals associated with pulmonary perfusion in other species, but its suitability and physiological effects in horses are unknown. This exploratory study aimed to determine whether intravenous administration of 100 mL of 23% HS produces a detectable change in thoracic impedance in anaesthetised horses, and to evaluate the physiological effects of repeated bolus administration. Six adult horses were anaesthetised twice using total intravenous anaesthesia. Hypertonic saline 23% was administered via a jugular catheter every 15 min (T15-T60). End-expiratory lung impedance (EELI), tidal impedance variation (TIV), heart rate (HR), and mean arterial pressure (MAP) were recorded at pre-injection, post-injection and end-sample timepoints. Plasma sodium (Na\n                    <jats:sup>+<\/jats:sup>\n                    ) and chloride (Cl\n                    <jats:sup>\u2212<\/jats:sup>\n                    ) concentrations were measured before each injection and 15 minutes after the final injection (T75), while urinary fractional excretion (FE) was calculated at T15 and T75. Changes over time were assessed using repeated-measures ANOVA, and FE was compared using paired t-tests. Following HS injection, there was a significant decrease in EELI (\n                    <jats:italic>p<\/jats:italic>\n                    &amp;lt; 0.01), and unanticipated haemodynamic effects were observed, including a significant decrease in MAP (\n                    <jats:italic>p<\/jats:italic>\n                    &amp;lt; 0.01) and increase in HR (\n                    <jats:italic>p<\/jats:italic>\n                    &amp;lt; 0.01), with hypotension (MAP below 70 mmHg) occurring in 62% of post-injection measurements. TIV decreased significantly (\n                    <jats:italic>p<\/jats:italic>\n                    = 0.02), and alterations in breathing pattern occurred in 24\/47 post-injection sample times, including transient tachypnoea, expiratory pauses, and crown-like breaths. Plasma Na\n                    <jats:sup>+<\/jats:sup>\n                    and Cl\n                    <jats:sup>\u2212<\/jats:sup>\n                    increased significantly over time (both\n                    <jats:italic>p<\/jats:italic>\n                    &amp;lt; 0.01), and FE of Na\n                    <jats:sup>+<\/jats:sup>\n                    and Cl\n                    <jats:sup>\u2212<\/jats:sup>\n                    increased between T15 and T75 (\n                    <jats:italic>p<\/jats:italic>\n                    = 0.01 and\n                    <jats:italic>p<\/jats:italic>\n                    = 0.02, respectively). Injection of 100 ml of 23% HS reduced EELI, supporting potential use for enhancing perfusion-related EIT signals. Repeated boluses produced clinically relevant decreases in MAP. Concurrent changes in TIV and breathing pattern may complicate interpretation of EIT-derived ventilation-perfusion relationships. Accordingly, repeated 23% HS boluses cannot currently be recommended for EIT contrast enhancement in horses. Further work is required to determine whether single-bolus or lower-concentration protocols provide adequate signal enhancement with less physiological disturbance.\n                  <\/jats:p>","DOI":"10.3389\/fvets.2026.1789443","type":"journal-article","created":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T04:27:15Z","timestamp":1781497635000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Feasibility and safety of repeated 23% hypertonic saline boluses for electrical impedance tomography contrast enhancement in anaesthetised horses"],"prefix":"10.3389","volume":"13","author":[{"given":"Kieran","family":"Smith","sequence":"first","affiliation":[{"name":"Murdoch University School of Veterinary and Life Sciences","place":["Perth, WA, Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anthea","family":"Raisis","sequence":"additional","affiliation":[{"name":"Murdoch University School of Veterinary and Life Sciences","place":["Perth, WA, Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fernando","family":"Moreno-Martinez","sequence":"additional","affiliation":[{"name":"Murdoch University School of Veterinary and Life Sciences","place":["Perth, WA, Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Byrne","sequence":"additional","affiliation":[{"name":"Murdoch University School of Veterinary and Life Sciences","place":["Perth, WA, Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina","family":"Mosing","sequence":"additional","affiliation":[{"name":"Anaesthesiology and Intensive Care, Clinical Centre for Small Animal Health and Research, Clinical Department for Small Animals and Horses, University of Veterinary Medicine Vienna","place":["Vienna, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,6,15]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"20","DOI":"10.3389\/fvets.2022.946911","article-title":"Thoracic electrical impedance tomography\u2014the 2022 veterinary consensus statement","volume":"9","author":"Brabant","year":"2022","journal-title":"Front Vet Sci."},{"key":"B2","doi-asserted-by":"publisher","first-page":"1140","DOI":"10.1152\/japplphysiol.00359.2020","article-title":"What hinders pulmonary gas exchange and changes distribution of ventilation in immobilized white rhinoceroses (Ceratotherium simum) in lateral recumbency?","volume":"129","author":"Mosing","year":"2020","journal-title":"J Appl Physiol."},{"key":"B3","doi-asserted-by":"publisher","first-page":"225","DOI":"10.1152\/japplphysiol.01090.2010","article-title":"Regional lung perfusion estimated by electrical impedance tomography in a piglet model of lung 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