Oxygenation Index (OI) Calculator

Formula

To calculate the Oxygenation Index (OI):

\[ OI = \frac{FiO2 \times MAP \times 100}{PaO2} \]

Where:

\(OI\) is the Oxygenation Index
\(FiO2\) is the fraction of inspired oxygen
\(MAP\) is the mean airway pressure
\(PaO2\) is the arterial oxygen tension

What is an Oxygenation Index?

The Oxygenation Index (OI) is a calculation used in intensive care medicine to measure the severity of lung disease, such as acute respiratory distress syndrome (ARDS). It is calculated using the fraction of inspired oxygen (FiO2), the mean airway pressure (MAP), and the arterial oxygen concentration (PaO2). A higher OI indicates more severe lung disease and a greater need for supportive care or intervention.

Example Calculation 1

Let's assume the following values:

Fraction of Inspired Oxygen (FiO2) = 0.5
Mean Airway Pressure (MAP) = 20
Arterial Oxygen Tension (PaO2) = 100

Using the formula:

\[ OI = \frac{0.5 \times 20 \times 100}{100} = 10 \]

The Oxygenation Index is 10.

Example Calculation 2

Let's assume the following values:

Fraction of Inspired Oxygen (FiO2) = 0.6
Mean Airway Pressure (MAP) = 25
Arterial Oxygen Tension (PaO2) = 80

Using the formula:

\[ OI = \frac{0.6 \times 25 \times 100}{80} = 18.75 \]

The Oxygenation Index is 18.75.