Fig. 2

Esophageal pressure swings during spontaneous breathing in normal conditions and with ARDS. a Esophageal pressure (P_es) trace of an awake, spontaneously breathing sheep with healthy lungs. Esophageal pressure swings (∆P_es) are around 4–6 cmH₂O and the respiratory rate is around 14–18 breaths per minute. b P_es trace of an awake, spontaneously breathing sheep with oleic acid-induced ARDS. Measured ∆P_es values are around 20–30 cmH₂O and respiratory rate is greatly increased. Personal experimental data of Thomas Langer and Andriy Batchinsky [49]