Cerebral oxygen saturation: graded response to carbon dioxide with isoxia and graded response to oxygen with Isocapnia

Simple item page
dc.contributor.authorMutch, W. Alan C
dc.contributor.authorPatel, Sunni R.
dc.contributor.authorShahidi, Ayda M.
dc.contributor.authorKulasekara, Susith I.
dc.contributor.authorFisher, Joseph A.
dc.contributor.authorDuffin, James
dc.contributor.authorHudson, Christopher
dc.date.accessioned2013-11-19T14:56:45Z
dc.date.available2013-11-19T14:56:45Z
dc.date.issued2013-02
dc.description.abstractBackground - Monitoring cerebral saturation is increasingly seen as an aid to management of patients in the operating room and in neurocritical care. How best to manipulate cerebral saturation is not fully known. We examined cerebral saturation with graded changes in carbon dioxide tension while isoxic and with graded changes in oxygen tension while isocapnic. Methodology/Principal Findings - The study was approved by the Research Ethics Board of the University Health Network at the University of Toronto. Thirteen studies were undertaken in healthy adults with cerebral oximetry by near infrared spectroscopy. End-tidal gas concentrations were manipulated using a model-based prospective end-tidal targeting device. End-tidal carbon dioxide was altered ±15 mmHg from baseline in 5 mmHg increments with isoxia (clamped at 110±4 mmHg). End-tidal oxygen was changed to 300, 400, 500, 80, 60 and 50 mmHg under isocapnia (37±2 mmHg). Twelve studies were completed. The end-tidal carbon dioxide versus cerebral saturation fit a linear relationship (R2 = 0.92±0.06). The end-tidal oxygen versus cerebral saturation followed log-linear behaviour and best fit a hyperbolic relationship (R2 = 0.85±0.10). Cerebral saturation was maximized in isoxia at end-tidal carbon dioxide of baseline +15 mmHg (77±3 percent). Cerebral saturation was minimal in isocapnia at an end-tidal oxygen tension of 50 mmHg (61±3 percent). The cerebral saturation during normoxic hypocapnia was equivalent to normocapnic hypoxia of 60 mmHg. Conclusions/Significance - Hypocapnia reduces cerebral saturation to an extent equivalent to moderate hypoxia.en_US
dc.description.sponsorshipInternal Funding, Department of Ophthalmology and Vision Sciencesen_US
dc.identifier.citationPLoS ONE 8 (2): e57881en_US
dc.identifier.doihttp://dx.doi.org/10.1371/journal.pone.0057881
dc.identifier.urihttp://hdl.handle.net/1993/22260
dc.publisherPLoSen_US
dc.rightsopen accessen_US
dc.subjectcerebral saturationen_US
dc.subjectneurocritical careen_US
dc.subjectIsoxiaen_US
dc.subjectIsocapniaen_US
dc.subjectgraded responseen_US
dc.titleCerebral oxygen saturation: graded response to carbon dioxide with isoxia and graded response to oxygen with Isocapniaen_US
dc.typeArticleen_US
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
journal_pone_0057881.pdf
Size:
342.98 KB
Format:
Adobe Portable Document Format
Description:
main article
Download
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
2.17 KB
Format:
Item-specific license agreed to upon submission
Description:
Download
Collections
University of Manitoba Scholarship
Rady Faculty of Health Sciences Scholarly Works