When Should CPAP or PEEP Be Considered

When should CPAP or PEEP be considered?

A) If a PaO₂ of at least 60 mm Hg with an FIO₂ of 0.5 or less cannot be achieved
B) If a PaO₂ of at least 50 mm Hg with an FIO₂ of 0.5 or less cannot be achieved
C) If a PaO₂ of at least 80 mm Hg with an FIO₂ of 0.5 or less cannot be achieved
D) If a PaO₂ of at least 60 mm Hg with an FIO₂ of 0.6 or less cannot be achieved