Fraction of inspired oxygen
Encyclopedia
Fraction of inspired oxygen (FiO2) is the percentage of oxygen concentration participating in gas exchange in the alveoli.
of oxygen
in arterial blood
(PaO2) and FiO2 is used as an indicator of hypoxemia
per the American-European Consensus Conference on lung injury. A high FiO2 has been shown to alter the ratio of PaO2/FiO2.
Uses
The ratio between partial pressurePartial pressure
In a mixture of ideal gases, each gas has a partial pressure which is the pressure which the gas would have if it alone occupied the volume. The total pressure of a gas mixture is the sum of the partial pressures of each individual gas in the mixture....
of oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
in arterial blood
Arterial blood
Arterial blood is the oxygenated blood in the circulatory system found in the lungs, the left chambers of the heart, and in the arteries. It is bright red in color, while venous blood is dark red in color...
(PaO2) and FiO2 is used as an indicator of hypoxemia
Hypoxemia
Hypoxemia is generally defined as decreased partial pressure of oxygen in blood, sometimes specifically as less than or causing hemoglobin oxygen saturation of less than 90%.-Distinction from anemia and hypoxia:...
per the American-European Consensus Conference on lung injury. A high FiO2 has been shown to alter the ratio of PaO2/FiO2.