The oxygen saturation index can be calculated without the need for an arterial blood sample.
Parameters:
(1) oxygen saturation as a decimal fraction
(2) FIO2 from 0.21 to 1.00
(3) mean airway pressure in cm water
oxygen saturation index =
= FIO2 * (mean airway pressure) / (oxygen saturation)
Interpretation:
• An oxygen saturation index of 6.5 to 7.79 indicates acute lung injury.
• An oxygen saturation index of >= 7.8 indicates acute respiratory distress syndrome.
