Normal mixed venous oxygen tension (PvO2) is approximately 40 mmHg, representing the balance between oxygen consumption and oxygen delivery. A true PvO2 measurement must come from a mixed venous blood sample containing venous drainage from the SVC, IVC, and the heart. Thus, the sample should be obtained from a pulmonary artery catheter. There are several factors that determine PvO2, which can be remembered using the mnemonic COALS:
- Cardiac output
- Oxygen consumption
- Amount of hemoglobin
- Loading of hemoglobin
- Saturation of hemoglobin
Of note, PvO2 can be used in lieu of SvO2 (mixed venous oxygen saturation), which is normally 65-75%.
Other References
- Jensen, Niels (2003). Clinical Arterial Blood Gas Analysis Link
Copyright Information
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.