Venous blood gas analysis

The use of venous blood gas analysis has been promoted as an alternative to arterial blood gas analysis to measure and monitor partial pressure of carbon dioxide (PaCO₂), pH and bicarbonate concentration. However, because venous blood gas values do not correlate directly with arterial blood gas values, there is considerable controversy as to whether venous blood gas analysis is clinically useful.

There are no prospective data regarding the utility of venous blood gas analysis in the assessment of chronic obstructive pulmonary disease or pneumonia.

Venous blood gas analysis alone is inadequate to accurately assess patients with respiratory failure; if venous blood gas analysis is performed and is abnormal, arterial blood gas analysis should be performed.