significance of central ABG

The patient with a low SvO2 is likely shunting blood and therefore not exchanging oxygen with other tissues that need it. The patient is usually mottled at this point in time. http://www.uptodate.com/home/content...=cc_medi/16828

It can be confusing, because it is related to delivery and consumption of oxygen. Decreased SvO2/ ScvO2 can result from failure to produce, and maintain oxygneation (hypoxia, hypovolemia, anemia,decreased perfusion). But, increased SvO2/ ScvO2 can result from failure of the tissues from using the oxygen that is present in the blood (shunting, interstitial edema, cells unable to take or ust teh oxygen being delivered, etc). Thus low and high values can be significant. It is really helpful to compare arterial ABG''s with venous gases to see how much oxygen consumption is really going on. There is a formula for this,but sorry to say I do not know it.