Table 2.

Quantification of hypoxemia using oxygenation and oxygenation saturation indices to classify the degree of severity of pediatric acute respiratory distress syndrome in patients undergoing invasive mechanical ventilation

	Mild	Moderate	Severe
OI	4 ≤ OI < 8	8 ≤ OI < 16	OI ≥ 16
OSI	5 ≤ OSI < 7.5	7.5 ≤ OSI < 12.3	≥ 12.3

OI - oxygenation index, based on the formula: MAP x FiO₂/PaO₂; OSI - oxygen saturation index based on the formula: MAP x FiO₂/SatO₂. When SatO₂ was used as a criterion for the diagnosis of pARDS, oxygen therapy should be titrated to achieve SaO₂ ≤ 97% for the OSI calculation. In patients undergoing non-invasive ventilation, there is currently no means to stratify the severity of pARDS, which is defined in these cases by an OI ≤ 300 or OSI ≤ 264.