Main clinical outcomes were defined as the development of pneumonia and extubation failure (need for reintubation within 48 h after endotracheal tube removal or inability for the patient to trigger and sustain spontaneous breathing after changing the setup of the mechanical ventilation to continuous spontaneous ventilation mode). Pneumonia was defined using Horan et al. pneumonia flow diagram (24 (link)). We defined early pneumonia (<5 post-operative days). and late pneumonia. Secondary outcomes/endpoints were numbers of ventilation days after surgery, length of stay in ICU and in hospital in days, tracheostomy and mortality rate at 30 days after trauma. Thoracic deformation was defined as the absence of symmetry of the chest wall after trauma on the X-ray.