Table 2

Comparison of the three systems

AIRVO 2
Constant flow
Steady air
Constant flow
Vivo 50
Constant pressure
p Values
Difference in tidal volume (mL)221.40±263.92257.30±315.06244.24±268.63p>0.99
Difference in PtcCO2 (mm Hg)−0.50±2.37−0.30±1.06−0.60±2.32p>0.05
Difference in RR (bpm)−3.26±2.14−3.17±4.93−4.18±2.68p>079
Difference in EIOP (cmH2O)−3.18±4.70−2.04±1.74−1.77±2.56p>0.85
Difference in EEOP (cmH2O)−0.51±2.800.71±2.341.02±3.99p>0.92
  • p Values in comparison between NHF-OTS 30 L/min and baseline.

  • difference EEOP, difference in end-expiration oesophageal pressure; difference EIOP, difference in end-inspiration oesophageal pressure; PtcCO2, transcutaneous carbon dioxide; RR, respiratory rate.