Purpose of review: Maintenance of adequate tissue oxygenation is an important task in intensive care units. In this context, venous oximetry by obtaining mixed venous oxygen saturation or central venous oxygen saturation has been discussed as useful monitoring parameters. This review discusses the physiology and clinical application of these parameters.
Recent findings: No study has so far demonstrated that venous oxygen saturation monitoring can reduce mortality in critically ill patients although length of stay has been decreased in cardiac surgery patients. Furthermore, pulmonary artery catheter usage does not affect outcome in critically ill patients. In contrast, early goal directed therapy for patients with severe sepsis or septic shock, which includes treatment goals for mean arterial pressure, central venous pressure, and central venous oxygen saturation, was able to increase survival in these patients. There is also evidence that central venous oxygen saturation measurement is beneficial in other types of shock.
Summary: Early goal directed therapy should be implemented in the initial resuscitation of septic patients. Measurement of central venous oxygen saturation can easily be applied in intensive care unit patients and offers a useful indirect indicator for the adequacy of tissue oxygenation.