For ScvO2 levels, what is the critical value indicating impaired tissue oxygenation?

ScvO2, or central venous oxygen saturation, is a critical parameter that reflects the balance between oxygen delivery and consumption at the tissue level. A ScvO2 level of less than 65% is indicative of impaired tissue oxygenation, suggesting that the body is not effectively utilizing or distributing the oxygen being delivered to the tissues.

When the ScvO2 falls below this threshold, it may point to several underlying issues, such as inadequate perfusion, increased oxygen demand, or impaired oxygen delivery, often seen in states of shock or severe illness. In well-functioning systems, ScvO2 levels should ideally be greater than 70%, with values below 65% showing that tissues may not be receiving sufficient oxygen to meet metabolic needs.

Higher values, above 65% and certainly those around or greater than 80%, generally reflect adequate tissue oxygenation and effective oxygen delivery, while lower ranges such as those between 25-30% or 35-50% suggest severely compromised tissue perfusion and oxygenation, which can lead to cellular injury and organ dysfunction. Understanding these levels is crucial for clinicians in critical care settings to assess patient status and guide therapeutic interventions effectively.