Intensity of Mechanical Ventilation

The aim of this thesis was to investigate the association of intensity of ventilation with outcome and the predictive value of its markers (i.e. driving pressure and mechanical power) as well as the effects of interventions proposed to decrease the intensity of ventilation, such as the use of automated modes of ventilation and prone positioning, in patients with and without the acute respiratory distress syndrome (ARDS).
In the first part of this thesis, we focused on patients without ARDS, in which we found that driving pressure and mechanical power did not increase the predictive validity of regularly used disease severity scores. Furthermore, in patients after cardiac surgery, the use of an automated mode of ventilation decreased the intensity of mechanical ventilation compared to conventional modes of ventilation. Finally, in patients without ARDS mechanical power was shown to have an association with outcome additional to that of its individual components.
The second part of this thesis focusses on patients with ARDS. Here we showed that changes in driving pressure caused by prone positioning, although better than other ventilatory parameters, have a poor predictive capacity for mortality. Lastly, in patients with ARDS due to COVID-19 a cumulative exposure to a higher intensity of ventilation was independently associated with worse outcome.