BACKGROUND: Changes in the clinical practice of mechanical ventilation during and after the coronavirus pandemic (COVID-19) worldwide could influence the clinical outcomes of critically ill patients with mechanical ventilation due to a generalization of these changes. Thus, the variability of the clinical response of different strategies in critically ill patients could be related to the existence of unidentified phenotypes that would be related to an increased risk of mortality and functional deterioration at the medium term. OBJECTIVES: The main objective will be to evaluate the worldwide clinical practice of mechanical Ventilation in critically ill patients, as well as the medium-term clinical outcomes for the description of phenotypes of critically ill patients treated with mechanical ventilation. The analysis of phenotypes and unsupervised pattern recognition over time could help to predict relevant clinical outcomes. This approach could improve personalized and precision medicine applicable to the ventilated patient. METHODOLOGY: An observational, prospective, non-interventional, international, and multicenter study will be carried out that will include adult critically ill patients requiring invasive or non-invasive mechanical ventilation for more than 12 hours. Analyzes of the variability of mortality and functional impairment at six months will be performed. Likewise, artificial intelligence analyzes (machine learning and neural networks) will be carried out.