Carolinas Core Concepts Core Concepts in EM; a repository for Carolinas lecture summaries.


Respiratory Master Class

  • VBG's have supplanted ABG's in the emergent analysis of acid/base status.  The venous pH is different by only 0.05 if the pH is 7.2 or higher.   Similarly, an abnormal venous lactate is 100% sensitive for an abnormal arterial lactate.
  • Pa02 measurements detect O2 levels dissolved in plasma, not bound to hemoglobin.  This will be falsely elevated in cyanide or carbon monoxide poisoning!
    • Gennis PR, et al.: The usefulness of peripheral venous blood in estimating acid-base status in acutely ill patients. Ann Emerg Med 14(9):845, 1985.
    • Weil MH, et al.: Difference in acid-base state between venous and arterial blood during cardiopulmonary resuscitation. N Engl J Med 315(3):153, 1986.
    • Younger JG, et al.: Relationship between arterial and peripheral venous lactate levels. Acad Emerg Med 3(7):730, 1996.