{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T19:12:58Z","timestamp":1791313978436,"version":"4.3.1"},"reference-count":25,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,9,10]],"date-time":"2021-09-10T00:00:00Z","timestamp":1631232000000},"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. Neurol."],"abstract":"<jats:p>Cerebral perfusion may be altered in sepsis patients. However, there are conflicting findings on cerebral autoregulation (CA) in healthy participants undergoing the experimental endotoxemia protocol, a proxy for systemic inflammation in sepsis. In the current study, a newly developed near-infrared spectroscopy (NIRS)-based CA index is investigated in an endotoxemia study population, together with an index of focal cerebral oxygenation.<\/jats:p><jats:p><jats:bold>Methods:<\/jats:bold> Continuous-wave NIRS data were obtained from 11 healthy participants receiving a continuous infusion of bacterial endotoxin for 3 h (<jats:ext-link>ClinicalTrials.gov<\/jats:ext-link> NCT02922673) under extensive physiological monitoring. Oxygenated\u2013deoxygenated hemoglobin phase differences in the (very)low frequency (VLF\/LF) bands and the Tissue Saturation Index (TSI) were calculated at baseline, during systemic inflammation, and at the end of the experiment 7 h after the initiation of endotoxin administration.<\/jats:p><jats:p><jats:bold>Results:<\/jats:bold> The median (inter-quartile range) LF phase difference was 16.2\u00b0 (3.0\u201352.6\u00b0) at baseline and decreased to 3.9\u00b0 (2.0\u20138.8\u00b0) at systemic inflammation (<jats:italic>p<\/jats:italic> = 0.03). The LF phase difference increased from systemic inflammation to 27.6\u00b0 (12.7\u201367.5\u00b0) at the end of the experiment (<jats:italic>p<\/jats:italic> = 0.005). No significant changes in VLF phase difference were observed. The TSI (mean \u00b1 SD) increased from 63.7 \u00b1 3.4% at baseline to 66.5 \u00b1 2.8% during systemic inflammation (<jats:italic>p<\/jats:italic> = 0.03) and remained higher at the end of the experiment (67.1 \u00b1 4.2%, <jats:italic>p<\/jats:italic> = 0.04). Further analysis did not reveal a major influence of changes in several covariates such as blood pressure, heart rate, PaCO<jats:sub>2<\/jats:sub>, and temperature, although some degree of interaction could not be excluded.<\/jats:p><jats:p><jats:bold>Discussion:<\/jats:bold> A reversible decrease in NIRS-derived cerebral autoregulation phase difference was seen after endotoxin infusion, with a small, sustained increase in TSI. These findings suggest that endotoxin administration in healthy participants reversibly impairs CA, accompanied by sustained microvascular vasodilation.<\/jats:p>","DOI":"10.3389\/fneur.2021.695705","type":"journal-article","created":{"date-parts":[[2021,9,10]],"date-time":"2021-09-10T06:30:39Z","timestamp":1631255439000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":8,"title":["Near-Infrared Spectroscopy-Derived Dynamic Cerebral Autoregulation in Experimental Human Endotoxemia\u2014An Exploratory Study"],"prefix":"10.3389","volume":"12","author":[{"given":"Nick","family":"Eleveld","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cornelia W. E.","family":"Hoedemaekers","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C. 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