TY - JOUR N2 - Near-infrared spectroscopy (NIRS)-derived measurement of oxidized cytochrome c oxidase concentration ([oxCCO]) has been used as an assessment of the adequacy of cerebral oxygen delivery. We report a case in which a reduction in conscious level was associated with a reduction in [oxCCO]. Hypoxaemia was induced in a 31-year-old, healthy male subject as part of an ongoing clinical study. Midway through the hypoxaemic challenge, the subject experienced an unexpected vasovagal event with bradycardia, hypotension and reduced cerebral blood flow (middle cerebral artery blood flow velocity decrease from 70 to 30 cm s(-1)) that induced a brief reduction in conscious level. An associated decrease in [oxCCO] was observed at 35 mm (-1.6 ?M) but only minimal change (-0.1 ?M) at 20-mm source-detector separation. A change in optical scattering was observed, but path length remained unchanged. This unexpected physiological event provides an unusual example of a severe reduction in cerebral oxygen delivery and is the first report correlating change in clinical status with changes in [oxCCO]. UR - http://dx.doi.org/10.1007/978-1-4614-7411-1_4 EP - 27 ID - discovery1399753 TI - Reduction of cytochrome C oxidase during vasovagal hypoxia-ischemia in human adult brain: a case study Y1 - 2013/// SN - 0065-2598 AV - public KW - Adult KW - Anoxia KW - Bradycardia KW - Brain KW - Cerebrovascular Circulation KW - Electron Transport Complex IV KW - Humans KW - Ischemia KW - Male KW - Oxygen KW - Peptides KW - Spectroscopy KW - Near-Infrared JF - Advances in Experimental Medicine and Biology A1 - Ghosh, A A1 - Kolyva, C A1 - Tachtsidis, I A1 - Highton, D A1 - Elwell, CE A1 - Smith, M N1 - © Springer Science+Business Media New York 2013. This article is published with open access at Springerlink.com. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited. VL - 789 SP - 21 ER -