Table 1 Airway pressure and resistance during high-flow tracheal oxygen in the bench experiment.
HFT flow rates (L/min) | p among flow rates | ||||||
|---|---|---|---|---|---|---|---|
10 | 20 | 30 | 40 | 50 | 60 | ||
Mean inspiratory P aw (cmH 2 O) | |||||||
Standard interface | −0.9 ± 0.6 | −1.1 ± 0.8 | −0.8 ± 0.7 | −0.7 ± 0.7 | −0.6 ± 0.8 | −0.4 ± 0.8 | 0.621 |
Modified interface | −1.1 ± 0.8 | −0.8 ± 0.8 | −0.3 ± 0.9 | 0.6 ± 1.1 | 2.1 ± 1.3 | 4.0 ± 1.4 | <0.001 |
p between interfaces | 0.130 | 0.153 | 0.003 | <0.001 | <0.001 | <0.001 | |
Mean expiratory P aw (cmH 2 O) | |||||||
Standard interface | 0.5 ± 0.3 | 0.6 ± 0.3 | 0.8 ± 0.3 | 1.0 ± 0.3 | 1.2 ± 0.3 | 1.5 ± 0.3 | <0.001 |
Modified interface | 0.9 ± 0.5 | 1.6 ± 0.6 | 2.6 ± 0.6 | 3.8 ± 0.6 | 5.3 ± 0.6 | 7.0 ± 0.7 | <0.001 |
p between interfaces | 0.004 | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 | |
Inspiratory resistance (cmH 2 O/L/s) | |||||||
Standard interface | 3.8 ± 0.4 | 3.8 ± 0.6 | 3.9 ± 0.7 | 4.1 ± 0.6 | 4.1 ± 0.5 | 4.4 ± 0.6 | 0.389 |
Modified interface | 4.5 ± 0.3 | 4.6 ± 0.6 | 5.5 ± 0.5 | 6.3 ± 0.2 | 6.2 ± 0.9 | 5.5 ± 1.7 | 0.002 |
p between interfaces | 0.014 | 0.001 | 0.002 | < 0.001 | < 0.001 | 0.166 | |
Expiratory resistance (cmH 2 O/L/s) | |||||||
Standard interface | 6.2 ± 1.0 | 6.2 ± 0.9 | 6.4 ± 0.7 | 6.5 ± 0.9 | 6.6 ± 0.9 | 6.6 ± 0.8 | 0.905 |
Modified interface | 7.6 ± 1.5 | 7.6 ± 1.1 | 8.7 ± 1.1 | 9.6 ± 1.1 | 10.5 ± 1.1 | 11.9 ± 1.3 | <0.001 |
p between interfaces | 0.009 | 0.002 | <0.001 | <0.001 | <0.001 | <0.001 | |
