How do you calculate AVDO2?

The AVDO2 was calculated according to the following formula: AVDO2 = Hb 1.34 (SaO2 SvO2) + 0.003 (PaO2 PvO2).

What does low SvO2 mean?

If SvO2 decreases, it indicates that the tissues are extracting a higher percentage of oxygen from the blood than normal. In otherwords, a decreased SvO2 indicates that the cardiac output is not high enough to meet tissue oxygen needs.

What does a-VO2 diff refer to?

The arteriovenous oxygen difference, or a-vO2 diff, is the difference in the oxygen content of the blood between the arterial blood and the venous blood. It is an indication of how much oxygen is removed from the blood in capillaries as the blood circulates in the body.

What is the O2 concentration in venous blood?

Oxygen delivery to the tissues Following circulation through the tissues, the average oxygen saturation in the venous blood returning to the right side of the heart (mixed venous blood) is typically about 75% in healthy individuals at rest, a figure which implies a considerable “reserve” in the oxygen delivery system.

What is the difference between po2 and SAO2?

PAO2 is the pressure exerted by O2 on the arterial wall. SAO2 is the percentage of hemoglobin binding sites that are occupied with O2. This is the main difference between PAO2 and SAO2.

How do you calculate cardiac output in cath lab?

CO is calculated as oxygen consumption divided by the arteriovenous oxygen concentration difference (in milliliters of oxygen). Remember O2 saturation percentages are converted to amount (or content) of O2 using the following formula: content (1.36 x hemoglobin x O2 saturation x 10).

Is SvO2 high or low in sepsis?

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].

What is a good SvO2?

SvO2 thus reflects the balance between oxygen delivery and oxygen demand [9]. The normal range for SvO2 is 65 to 75% [4,10].

What is the A-VO2 difference at rest?

At rest, arteriovenous oxygen difference is normally 4.5 mL/100 mL/min (approximately 23% extraction), and at V ˙ O 2 max this difference is commonly close to 16 mL/100 mL/min (about 80–85% extraction) (Rowell, 1993b).

Why does VO2 increase during exercise?

VO2 During Exercise Since the ATP energy used by your muscles is generated with the aid of oxygen, it follows that an increase in exercise intensity will result in an increase in muscular oxygen demands. Therefore, increased exercise intensity ultimately corresponds to an increased VO2 .

What is the normal range for SvO2?

What does high venous O2 mean?

An increase in central venous saturation is seen when oxygen delivery increases more than consumption and/or when oxygen consumption is reduced without an equivalent reduction in delivery. During normal aerobic metabolism at rest, about 25 % of total oxygen, or 200 – 250 ml/min, is extracted from the blood.