Poulin, Marc J.Vantanajal, Jimmy S.2005-08-162005-08-162004Vantanajal, J. S. (2004). Cerebral blood flow responses to sustained alterations in end-tidal PO2 and PCO2 in humans (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/169490612975819http://hdl.handle.net/1880/42088Bibliography: p. 113-130Some pages are in colour.The techniques of transcranial Doppler ultrasound and dynamic end-tidal forcing were used to study the dynamics of the middle cerebral artery peak flow velocity (V P) (i.e. index of cerebral blood flow) response to 60 min of sustained isocapnic hypoxia, isocapnic hyperoxia, euoxic hypocapnia, and euoxic hypercapnia in humans. Each protocol involved two 60-min interventions, with a 60-min recovery period between tests. Peak flow velocity increased significantly during hypoxia (14.7%) and decreased during hyperoxia (11.8%). During hypercapnia, VP increased significantly (33.6%) and remained elevated. There was no evidence of adaptation during these protocols. However, a significant adaptation was observed during hypocapnia. After an initial decrease (39%), VP increased significantly and stabilized at 25.2% below baseline. This adaptive component was found to be significantly faster during the second intervention. There were no significant differences between the first and second intervention for the remaining protocols.xviii, 163 leaves : ill. ; 30 cm.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.master thesis10.11575/PRISM/16949AC1 .T484 2004 V365