Accuracy of delivered airway pressure and work of breathing estimation during proportional assist ventilation: a bench study

Background Proportional assist ventilation+ (PAV+) delivers airway pressure (Paw) in proportion to patient effort (Pmus) by using the equation of motion of the respiratory system. PAV+ calculates automatically respiratory mechanics (elastance and resistance); the work of breathing (WOB) is estimated by the ventilator. The accuracy of Pmus estimation and hence accuracy of the delivered Paw and WOB calculation have not been assessed. This study aimed at assessing the accuracy of delivered Paw and calculated WOB by PAV+ and examining the factors influencing this accuracy.