Driving Pressure in Trauma

Traumatic chest injuries are responsible for significant morbidity and the cause of trauma-related death in 20%-25% of cases. Thoracic trauma can include multiple injuries, mainly osseous (ribs, sternal fractures, flail chest), pulmonary contusions or lacerations, pneumothoraces and pleural effusions, and sometimes involve wounds to the heart and vessels (aortic dissection, cardiac contusion) or diaphragm. Following trauma, patients with thoracic injuries are at risk of developing acute respiratory distress syndrome (ARDS). This worsening of respiratory function can lead to requirement for mechanical ventilation. In addition, changes to gas exchange may also be generated or aggravated by mechanical ventilation as a result of barotrauma, biotrauma, or ventilation-associated pneumonia. Many mechanical ventilation strategies have been tried in trauma patients in the last 30 years to determine the optimal method of maximizing gas exchange with minimal lung damage. The driving pressure of the respiratory system has been shown to strongly correlate with mortality in a recent large retrospective ARDSnet study. Respiratory system driving pressure \[plateau pressure-positive end-expiratory pressure (PEEP)\] does not account for variable chest wall compliance especially in cases of chest trauma. Esophageal manometry can be utilized to determine transpulmonary driving pressure. A recent study suggests that utilizing PEEP titration to target positive transpulmonary pressure via esophageal manometry causes both improved elastance and driving pressures. Treatment strategies leading to decreased respiratory system and transpulmonary driving pressure at 24 h may be associated with improved 28 day mortality. However, currently no specific study with chest trauma patients exists. We propose to investigate the effect of hight transpulmonary driving pressure on duration on mechanical ventilation, length of stay and mortality in patients with sever chest trauma.