SvO2 is defined as what?

SvO2 is defined as what?

• A. Arterial oxygen saturation
• B. Mixed venous oxygen saturation
• C. Central venous oxygen saturation
• D. Alveolar oxygen tension

Answer: (B)

SvO2 represents the oxygen saturation of mixed venous blood, which is the blood returning to the right heart from all tissues after oxygen has been extracted. It’s measured in the pulmonary artery and reflects the balance between oxygen delivery (DO2) and tissue oxygen consumption (VO2). This makes SvO2 a global indicator of the body’s oxygen debt or supply-demand status. Arterial oxygen saturation is SaO2, not SvO2, and reflects oxygen carried by arterial blood. Central venous oxygen saturation (ScvO2) comes from venous blood in the upper body via a central venous catheter, not the mixed venous blood from all systemic tissues. Alveolar oxygen tension (PaO2) is a measure of oxygen partial pressure in the alveoli, not blood oxygen saturation.

SvO2 represents the oxygen saturation of mixed venous blood, which is the blood returning to the right heart from all tissues after oxygen has been extracted. It’s measured in the pulmonary artery and reflects the balance between oxygen delivery (DO2) and tissue oxygen consumption (VO2). This makes SvO2 a global indicator of the body’s oxygen debt or supply-demand status.

Arterial oxygen saturation is SaO2, not SvO2, and reflects oxygen carried by arterial blood. Central venous oxygen saturation (ScvO2) comes from venous blood in the upper body via a central venous catheter, not the mixed venous blood from all systemic tissues. Alveolar oxygen tension (PaO2) is a measure of oxygen partial pressure in the alveoli, not blood oxygen saturation.