Practice of ventilation and clinical outcomes in different age groups of critically ill patients

Invasive mechanical ventilation is often essential to support critically ill patients with respiratory failure. However, mechanical ventilation may also contribute to further lung injury through mechanisms such as volutrauma, barotrauma, atelectrauma and biotrauma, underscoring the importance of lung-protective ventilation strategies. Despite this, evidence regarding optimal ventilation strategies remains limited. Clinical practice often relies on physician experience and extrapolation from adult data. Yet, physiological and developmental differences between children and adults, as well as across pediatric and adult age groups, challenge the validity of such extrapolations and leave uncertainty regarding the most appropriate ventilation strategies for different patient populations.
The studies presented in this thesis aim to improve the understanding of ventilation practices in both critically ill children and adults.
The first part of this thesis focuses on pediatric patients and describes the epidemiology, ventilation practices and outcomes in critically ill children across different age groups worldwide. It further identifies potentially modifiable ventilation-related factors independently associated with clinical outcomes. In addition, changes in ventilation intensity following extracorporeal membrane oxygenation (ECMO) are explored, as well as their association with clinical outcomes.
The second part focuses on adult patients and investigates the association between age and extubation failure in neurocritical care patients. It also evaluates the impact of a high positive end-expiratory pressure (PEEP)/low fraction of inspired oxygen (FiO2) strategy compared with a low PEEP/high FiO2 strategy in patients with coronavirus disease 2019 (COVID-19) related acute respiratory distress syndrome (ARDS). In addition, it explores whether the timing of spontaneous ventilation is associated with outcomes in COVID-ARDS patients.
Together, this thesis contributes to a better understanding of global ventilation practices in both children and adults and identifies potentially modifiable ventilation-related factors associated with clinical outcomes.