{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T06:23:22Z","timestamp":1787639002971,"version":"build-2736575974"},"reference-count":33,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T00:00:00Z","timestamp":1787616000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pharmacol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      Norepinephrine is an effective vasopressor for preventing and managing spinal anesthesia-induced hypotension during cesarean delivery. Nevertheless, data regarding the 95% effective dose (ED\n                      <jats:sub>95<\/jats:sub>\n                      ) of continuous norepinephrine infusion in obese parturients remain scarce.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      This prospective dose-finding study enrolled parturients scheduled for elective cesarean delivery under spinal anesthesia. Participants were stratified into two groups based on body mass index (BMI): non-obese group (BMI &amp;lt;30\u00a0kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      ) and obese group (BMI \u226530\u00a0kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      ). Intravenous norepinephrine infusion was initiated at a dose of 0.01\u00a0\u03bcg\/kg\/min in the first participant, with subsequent dosages adjusted according to the preceding patient\u2019s response using a biased coin design up-and-down sequential method. Spinal anesthesia-induced hypotension was defined as a mean arterial pressure of below 65\u00a0mmHg sustained for more than 1\u00a0minute within 30\u00a0min following intrathecal injection. The 95% effective dose (ED\n                      <jats:sub>95<\/jats:sub>\n                      ) was estimated via isotonic regression coupled with bias-corrected bootstrapping. Maternal and neonatal outcomes, including adverse events, were recorded.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Eighty parturients were included in the analysis. The ED\n                      <jats:sub>95<\/jats:sub>\n                      of norepinephrine was determined to be 0.045\u00a0\u03bcg\/kg\/min (95% confidence interval [CI], 0.03\u20130.05\u00a0\u03bcg\/kg\/min) in the non-obese group and 0.0662\u00a0\u03bcg\/kg\/min (95% CI, 0.055\u20130.075\u00a0\u03bcg\/kg\/min) in the obese group. No significant differences were observed in maternal or neonatal outcomes between the two cohorts.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The findings indicate that obese parturients require a significantly higher prophylactic dose of norepinephrine infusion to prevent spinal anesthesia-induced hypotension compared to the non-obese counterparts. These results underscore the importance of individualized dosing strategies based on BMI to optimize hemodynamic management in obese parturients undergoing cesarean delivery.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphar.2026.1905008","type":"journal-article","created":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T05:35:49Z","timestamp":1787636149000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["ED95 determination of continuous norepinephrine infusion for preventing spinal anesthesia-induced hypotension in obese parturients during cesarean delivery"],"prefix":"10.3389","volume":"17","author":[{"given":"Rui","family":"Ran","sequence":"first","affiliation":[{"name":"Department of Anesthesiology, Chongqing Health Center for Women and Children, Women and Children\u2019s Hospital of Chongqing Medical University","place":["Chongqing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Limeng","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, First Clinical College, Chongqing Medical University","place":["Chongqing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenqian","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Chongqing Health Center for Women and Children, Women and Children\u2019s Hospital of Chongqing Medical University","place":["Chongqing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jing","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Chongqing Health Center for Women and Children, Women and Children\u2019s Hospital of Chongqing Medical University","place":["Chongqing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaofeng","family":"Lei","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Chongqing Health Center for Women and Children, Women and Children\u2019s Hospital of Chongqing Medical University","place":["Chongqing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jin","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology, Chongqing Health Center for Women and Children, Women and Children\u2019s Hospital of Chongqing Medical University","place":["Chongqing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,8,25]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"540","DOI":"10.1213\/ANE.0000000000006244","article-title":"Manually controlled, continuous infusion of phenylephrine or norepinephrine for maintenance of blood pressure and cardiac output during spinal anesthesia for cesarean delivery: a double-blinded randomized study","volume":"136","author":"Belin","year":"2023","journal-title":"Anesth. 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