Endpoints
LUNG
The primary objectives of this study were to assess the effects of prone position on arterial oxygenation (as defined by the PaOSecondary endpoints of the study were the effects of prone position on:Breathing pattern: respiratory rate, inspiratory effort (the negative deflection of Gas exchange: PaCORespiratory mechanics: The end-expiratory Lung inflation pattern, measured with the EIT globally and regionally in the four regions of interests (ROI: ventral, mid-ventral, mid-dorsal, dorsal-Additional file Analyzed EIT outcomes were: global and regional tidal volume, expressed in arbitrary units and calculated on a pixel-by-pixel basis; global and regional lung compliance, calculated as the ratio of tidal volume to quasi-static transpulmonary driving pressure; amount of pendelluft, expressed in terms of % of tidal volume (Additional file Respiratory mechanics and lung inflation pattern were analyzed according to a methodology described elsewhere [