Difference between Scvo2 and Svo2

ScvO2 only measures venous blood returning from the upper half of the body, while SvO2 samples the true mixed venous blood leaving the right heart. Central (ScvO2) is normally slightly lower than mixed (SvO2), but is often higher than SvO2 in patients in shock.

1. What does ScvO2 mean?
2. What does a high ScvO2 mean?
3. How is ScvO2 measured?
4. What is SvO2 used for?
5. Is SvO2 high or low in sepsis?
6. What is the normal range of SaO2?
7. What is a normal PvO2?
8. What is mixed venous blood?
9. What is normal CVP?
10. What is the CaO2?
11. Why is SvO2 high in septic shock?
12. How can you tell ABG from VBG?

What does ScvO2 mean?

ScvO2 refers to hemoglobin saturation of blood in the superior vena cava and SvO2 refers to the same measurement in blood from the proximal pulmo- nary artery. The earliest clinical reports of the use of such data were of ScvO2 in the coronary care unit [1].

What does a high ScvO2 mean?

ScvO2 is normally < SvO2 because it contains predominantly SVC blood from the upper body — blood from the upper body has a higher oxygen extraction ratio, and thus a lower SO2 than IVC blood — of major organs at rest, the brain has high oxygen extraction ratio and the kidneys have the lowest.

How is ScvO2 measured?

ScvO2 should be measured from the tip of a central venous catheter placed close to, or within, the right atrium to reduce measurement error. ... Consequently, the use of pulmonary artery catheters to monitor critically ill patients and to guide therapy has diminished substantially (4).

What is SvO2 used for?

Mixed venous oxygen saturation (SvO2) can help to determine whether the cardiac output and oxygen delivery is high enough to meet a patient's needs. It can be very useful if measured before and after changes are made to cardiac medications or mechanical ventilation, particularly in unstable patients.

Is SvO2 high or low in sepsis?

Current guidelines recommend maintaining central venous oxygen saturation (ScvO₂) higher than 70% in patients with severe sepsis and septic shock.

What is the normal range of SaO2?

The reading may be referred to as SaO2. Readings vary from 0 to 100%. Normal readings in a healthy adult, however, range from 94% to 100%. The term SpO2 means the SaO2 measurement determined by pulse oximetry.

What is a normal PvO2?

Mixed venous saturation can help assess tissue oxygen delivery. From this equation, one can see that SvO2 varies directly with SaO2, Hg, cardiac output and inversely with VO2. The normal SvO2 is 65-75%, which denotes tissue oxygen extraction to be 25-35%. Normal PvO2 is 35-45mmHg.

What is mixed venous blood?

Accepted: 18 October 2008. True mixed venous blood is derived from a pool of venous blood entering the pulmonary artery via the great veins in the chest. It contains blood which has traversed all systemic capillary beds capable of extracting oxygen, and is thoroughly mixed by the right ventricle.

What is normal CVP?

Central venous pressure is an assessment of venous return, blood volume and, indirectly, of cardiac output. Normal CVP is between 0 and 8 cmH₂O (1–6 mmHg).

What is the CaO2?

Abstract. Rationale: PaO2 and SaO2 are commonly measured in respiratory practice, but arterial oxygen content (CaO2) refers to the volume of oxygen delivered to the tissues per unit blood volume.

Why is SvO2 high in septic shock?

Because septic shock is often characterized by high cardiac output and low extraction oxygen capacities, high values of SvO₂ or central venous blood oxygen saturation can be observed [10,11] as confirmed in the study by Velissaris and colleagues [1].

How can you tell ABG from VBG?

As discussed earlier, a VBG gives you the same information as an ABG. However, this information is going to be different since it's obtained from the venous as opposed to the arterial side. The most obvious difference will be in PO2 which, of course, will be markedly lower in the venous side than in the arterial side.