{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T08:27:00Z","timestamp":1789979220391,"version":"4.0.1"},"reference-count":27,"publisher":"American Physiological Society","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal of Applied Physiology"],"published-print":{"date-parts":[[2013,9,1]]},"abstract":"<jats:p> We investigated 1) the regional distribution of cerebral blood flow (CBF), 2) the influence of end-tidal Pco<jats:sub>2<\/jats:sub> (Pet<jats:sub>CO<\/jats:sub><jats:sub>2<\/jats:sub>) on CBF, and 3) the potential for an extracranial blood \u201csteal\u201d from the anterior brain region during passive hyperthermia. Nineteen (13 male) volunteers underwent supine passive heating until a steady-state esophageal temperature of 2\u00b0C above resting was established. Measurements were obtained 1) during normothermia (Normo), 2) during poikilocapnic hyperthermia (Hyper), and 3) during hyperthermia with Pet<jats:sub>CO<\/jats:sub><jats:sub>2<\/jats:sub> and end-tidal Po<jats:sub>2<\/jats:sub> clamped to Normo levels (Hyper-clamp). Blood flow in the internal carotid (Q\u0307<jats:sub>ica<\/jats:sub>), vertebral (Q\u0307<jats:sub>VA<\/jats:sub>), and external carotid (Q\u0307<jats:sub>eca<\/jats:sub>) arteries (Duplex ultrasound), blood velocity of the middle cerebral (MCAv) and posterior cerebral (PCAv) arteries (transcranial Doppler), and cutaneous vascular conductance on the cheek (cheek CVC; Doppler velocimetry) were measured at each stage. During Hyper, Pet<jats:sub>CO<\/jats:sub><jats:sub>2<\/jats:sub> was lowered by 7.0 \u00b1 5.2 mmHg, resulting in a reduction in Q\u0307<jats:sub>ica<\/jats:sub> (\u221218 \u00b1 17%), Q\u0307<jats:sub>va<\/jats:sub> (\u221231 \u00b1 21%), MCAv (\u221222 \u00b1 13%), and PCAv (\u221218 \u00b1 10%) compared with Normo ( P &lt; 0.05). The reduction in Q\u0307<jats:sub>VA<\/jats:sub> was greater than that in Q\u0307<jats:sub>ICA<\/jats:sub> ( P = 0.017), MCAv ( P = 0.047), and PCAv ( P = 0.034). Blood flow\/velocity was completely restored in each intracranial vessel (ICA, VA, MCA, and PCA) during Hyper-clamp. Despite a \u223c250% increase in Q\u0307<jats:sub>ECA<\/jats:sub> and a subsequent increase in cheek CVC during Hyper compared with Normo, reductions in Q\u0307<jats:sub>ICA<\/jats:sub> were unrelated to changes in Q\u0307<jats:sub>ECA<\/jats:sub>. These data provide three novel findings: 1) hyperthermia attenuates Q\u0307<jats:sub>VA<\/jats:sub> to a greater extent than Q\u0307<jats:sub>ICA<\/jats:sub>, 2) reductions in CBF during hyperthermia are governed primarily by reductions in arterial Pco<jats:sub>2<\/jats:sub>, and 3) increased Q\u0307<jats:sub>ECA<\/jats:sub> is unlikely to compromise Q\u0307<jats:sub>ICA<\/jats:sub> during hyperthermia. <\/jats:p>","DOI":"10.1152\/japplphysiol.00394.2013","type":"journal-article","created":{"date-parts":[[2013,7,4]],"date-time":"2013-07-04T04:02:41Z","timestamp":1372910561000},"page":"653-659","source":"Crossref","is-referenced-by-count":82,"title":["Regional changes in brain blood flow during severe passive hyperthermia: effects of Pa<sub>CO<sub>2<\/sub><\/sub> and extracranial blood flow"],"prefix":"10.1152","volume":"115","author":[{"given":"Anthony R.","family":"Bain","sequence":"first","affiliation":[{"name":"Center for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan, British Columbia, Canada;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kurt J.","family":"Smith","sequence":"additional","affiliation":[{"name":"Center for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan, British Columbia, Canada;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nia C.","family":"Lewis","sequence":"additional","affiliation":[{"name":"Center for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan, British Columbia, Canada;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Glen E.","family":"Foster","sequence":"additional","affiliation":[{"name":"Center for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan, British Columbia, Canada;"},{"name":"School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada; and"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kevin W.","family":"Wildfong","sequence":"additional","affiliation":[{"name":"Center for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan, British Columbia, Canada;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher K.","family":"Willie","sequence":"additional","affiliation":[{"name":"Center for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan, British Columbia, Canada;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geoffrey L.","family":"Hartley","sequence":"additional","affiliation":[{"name":"Department of Kinesiology, Brock University, St. Catharines, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephen S.","family":"Cheung","sequence":"additional","affiliation":[{"name":"Department of Kinesiology, Brock University, St. Catharines, Ontario, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philip N.","family":"Ainslie","sequence":"additional","affiliation":[{"name":"Center for Heart, Lung, and Vascular Health, University of British Columbia, Okanagan, British Columbia, Canada;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1972.33.4.418"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1161\/HYPERTENSIONAHA.107.101014"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00784.2010"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00475.2009"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00035.2011"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2009.172023"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00332.2007"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00010.2008"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1113\/expphysiol.2008.042143"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00247.2011"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1227\/00006123-199305000-00006"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2008.165118"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2012.00308"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2011.212118"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1016\/j.neuroimage.2010.12.079"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2002.030023"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1964.19.3.531"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00988.2011"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2012.230425"},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2010.204461"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1161\/01.STR.25.1.17"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1993.74.5.2566"},{"key":"B23","doi-asserted-by":"publisher","DOI":"10.1016\/j.jneumeth.2011.01.011"},{"key":"B24","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2012.228551"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00712.2005"},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.01043.2001"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.2001.91.2.929"}],"container-title":["Journal of Applied Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.physiology.org\/doi\/pdf\/10.1152\/japplphysiol.00394.2013","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,9,8]],"date-time":"2019-09-08T20:10:11Z","timestamp":1567973411000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.physiology.org\/doi\/10.1152\/japplphysiol.00394.2013"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,9,1]]},"references-count":27,"journal-issue":{"issue":"5","published-print":{"date-parts":[[2013,9,1]]}},"alternative-id":["10.1152\/japplphysiol.00394.2013"],"URL":"https:\/\/doi.org\/10.1152\/japplphysiol.00394.2013","relation":{},"ISSN":["8750-7587","1522-1601"],"issn-type":[{"value":"8750-7587","type":"print"},{"value":"1522-1601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2013,9,1]]}}}