PO2, SaO2, CaO2 are all related but different. If the lungs are normal, then PaO2 is affected only by the alveolar PO2 (PAO2), which is determined by the fraction of inspired oxygen, the barometric pressure and the PaCO2 (i.e., the alveolar gas equation).

How do you calculate PO2 from PaO2?

The alveolar gas equation is used to calculate alveolar oxygen partial pressure: PAO2 = (Patm – PH2O) FiO2 – PACO2 / RQ.

What is PaO2 called?

Partial pressure of oxygen (PaO2). This measures the pressure of oxygen dissolved in the blood and how well oxygen is able to move from the airspace of the lungs into the blood.

What does PO2 stand for?

Values of partial pressure of oxygen (PO2) and of carbon dioxide (PCO2) were measured by means of blood gas electrodes.

Is pa02 the same as O2?

PaO2 values are always much lower than oxygen saturation values. This is simply a reflection of the oxygen saturation curve (figure above). For example, a saturation of 88% correlates to a PaO2 of ~55mm. We’re generally comfortable with a saturation of 88%, but a PaO2 of 55mm may cause concern.

Is SaO2 and SpO2 the same?

Conclusion: Oxygen saturation results determined of different ways are often not identical. The difference between SaO2 and SpO2 are often more 3 pp when SpO2 results obtained from fingertip less than 94%.

What is PaO2 SaO2 and SpO2?

SpO2 = oxygen saturation as measured by pulse oximeter. SaO2 = oxygen saturation as measured by blood analysis (e.g. a blood gas) PaO2 = partial pressure of oxygen in the blood, as measured by blood analysis..dyspnea.

What is pO2 and SO2?

It is important to understand the difference between the pO2, the oxygen saturation (often called SO2 or SaO2), the oxygen content and the oxygen delivery rate. The pO2 represents the partial pressure of oxygen or the gas tension. Normal pO2 in arterial blood is only 100 mmHg.

What is pO2 mmHg?

pO2. Partial pressure of oxygen, or oxygen content, in mmHg. pO2 > 80 mmHg. pCO2. Partial pressure of carbon dioxide, or carbon dioxide content, in mmHg.

What is pO2 in blood gas?

pO2: This is measured by a pO2 electrode. It is the partial pressure (tension) of oxygen in a gas phase in equilibrium with blood. High or low values indicate blood hyperoxia or hypoxia, respectively. pO2 in venous blood is lower than arterial blood due to oxygen extraction by peripheral tissues.

What is the difference between PO2 and o2 saturation?

Oxygen saturation can be assessed by SaO2 or SpO2. SaO2 is oxygen saturation of arterial blood, while SpO2 is oxygen saturation as detected by the pulse oximeter. The partial pressure of oxygen is expressed as PO2, and the partial pressure of arterial blood is expressed as PaO2.

What is normal PaO2?

Normal Results Partial pressure of oxygen (PaO2): 75 to 100 millimeters of mercury (mm Hg), or 10.5 to 13.5 kilopascal (kPa) Partial pressure of carbon dioxide (PaCO2): 38 to 42 mm Hg (5.1 to 5.6 kPa) Arterial blood pH: 7.38 to 7.42.

What is normal PO2 on ABG?

Most healthy adults have a PaO2 within the normal range of 80–100 mmHg. If a PaO2 level is lower than 80 mmHg, it means that a person is not getting enough oxygen. A low PaO2 level can point to an underlying health condition, such as: emphysema.

How does SpO2 correlate with PaO2?

SpO2 correlated well with arterial pO2 as predicted by the standard oxygen-hemoglobin dissociation curve in a undifferentiated critically ill patient population. In this study, a SpO2 >90% correlated with an arterial pO2 >60 mmHg more than 94% of the time.

What is a good pa02?

Since a normal PaO2 is between 90-100 mmHg, some people may think that an O2 saturation of 90 is normal as well — after all 90 was a pretty good grade to get in school. An O2 sat of 90% corresponds to a PaO2 of 60 mmHg. This is the minimum oxygen concentration providing enough oxygen to prevent ischemia in tissues.

Which is more important SaO2 or PaO2?

PaO2 is the most important (but not the only) determinant of SaO2. Other determinants of SaO2 for a given PaO2 are conditions that shift the position of the oxygen dissociation curve left or right, such as temperature, pH, PaCO2 and level of 2,3-DPG in the blood.