Intensity of ventilation and prognostic classification: Studies in the ICU and the OR

This thesis, entitled ‘Intensity of ventilation––studies in the ICU and the OR’, is a collection of clinical investigations in critically ill patients under invasive ventilation and surgery patients receiving intraoperative ventilation during general anesthesia. The main findings of this thesis are that in patients with COVID–19 ARDS severity and mortality between severity classes changes substantially in the first days of mechanical ventilation. For daily practice, reclassification of ARDS in time is advised as it improves prognostication compared to classification at the first day of invasive ventilation. Furthermore, in this thesis we showed that both driving pressure and mechanical power of ventilation have independent associations with diverse outcomes in critically ill patients and surgical patients undergoing mechanical ventilation. Driving pressure and mechanical power of ventilation should be monitored to give insight in the amount of energy transferred to the respiratory system. Minimizing driving pressure and mechanical power of ventilation could have the potential to become a lung protective ventilation strategy, but the causal relationship with patient outcome needs to be studied.