Fig. 2.

Percentage of difference between measured airway pressure and theoretical airway pressure (%ΔP _aw) at 25, 50, 75 and 100 % of inspiration with different inspiratory trigger (IT) (a), muscular pressure (P _mus) (b) and positive end-expiratory pressure (PEEP) (c) under normal respiratory mechanics. Difference between $P_{{\text{aw}}_{\text{meas}}}$ and $P_{{\text{aw}}_{\text{th}}}$ is expressed in percentage of $P_{{\text{aw}}_{\text{th}}}$ (%ΔP _aw = ($P_{{\text{aw}}_{\text{meas}}}$ − $P_{{\text{aw}}_{\text{th}}}$)/$P_{{\text{aw}}_{\text{th}}}$ × 100). Resistance = 10 cmH₂O/L/s; compliance = 60 mL/cmH₂O; gain = 60 %; and respiratory rate = 20/min; a different IT at 0.8, 5 and 15 L/min; P _mus = 10 cmH₂O; PEEP = 5 cmH₂O. b Different P _mus at 10 and 15 cmH₂O; IT 5 L/min; PEEP = 5 cmH₂O; c different PEEP at 0 and 5 cmH₂O; IT 5 L/min; P _mus 10 cmH₂O