I read with interest the article by Malinoski et al1 on the correlation of central venous and arterial blood gas measurements in mechanically ventilated trauma patients.1
As a clinical toxicologist, I am interested in data regarding the range of values for central venous oxygen saturation for the purposes of confirming suspected acute cyanide exposures. Cyanide binds mitochondrial cytochrome aa3, thus preventing oxygen utilization and resulting in a rise in venous oxygen saturation. To identify how much of a rise is clinically important, we must first understand the “normal” range of central venous blood oxygen saturation levels in a variety of clinical settings. Studies have been performed in healthy volunteers2 and in the critical care setting3,4; however, these papers date back to the 1950s and early 1970s.
Wills B. Venous Blood Oxygen Saturation. Arch Surg. 2006;141(7):716. doi:10.1001/archsurg.141.7.716-a