Fig. 2

End-expiratory caudal transpulmonary pressure (left) and respiratory system elastance (right). Legend: CENP, continuous external negative pressure; PEEP, positive end-expiratory pressure. Triangles indicate different shell positions (abdomen and thorax), colours represent different PEEP levels, super-posed numbers indicate significance (P < 0.05) of the respective CENP level compared with the CENP level of the number and stars indicate difference between both positions