Critical O2 Delivery in Rat Brain

  • Robert Schlichtig
  • Jill Herrick
  • Edwin M. Nemoto
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 345)


As O2 delivery (DO2) of whole body,1,2 intestine,3,4 liver,5 or skeletal muscle6 is progressively decreased in anesthetized animals, O2 consumption (VO2) is initially maintained constant via increased O2 extraction by the tissues (O2 supply independence). However, below a critical threshold DO2 value (DO2c), VO2 of these organs decreases in proportion to DO2 (O2 supply dependence). More importantly, dysoxia (i.e. O2 demand that exceeds O2 supply)7 appears to commence at the onset of liver O2 supply dependence, as reflected by the simultaneous decrease in VO2 and increase in hepatic mitochondrial reduction.5 Accordingly, it tentatively appears that dysoxia may be identified, in liver at least, by the DO2c inflection of a biphasic VO2- DO2 relation.


Cerebral Blood Flow Mean Arterial Pressure Extraction Ratio Superior Sagittal Sinus Immobilization Stress 
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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • Robert Schlichtig
    • 1
    • 2
  • Jill Herrick
    • 2
  • Edwin M. Nemoto
    • 1
  1. 1.Department of Anesthesiology and Critical Care MedicineUniversity of PittsburghPittsburghUSA
  2. 2.Veterans Affairs Medical CenterUniversity DrivePittsburghUSA

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