Younger age |
Lower acuity of illness (APACHE score) |
Able to cooperate, better neurologic score |
Less air leaking, intact dentition |
Moderate hypercarbia (PaCO2 >45 mmHG, <92 mmHG) |
Moderate acidemia (pH <7.35, >7.10) |
Improvements in gas exchange and heart respiratory rates within first two hours |