Arterial blood gas analysis utility in predicting lung injury in blunt chest trauma

thoracic trauma is one of the leading causes of death in all age groups and accounts for 25-50 % of all traumatic injuries. With the term lung injury in blunt chest trauma, we identified a spectrum of conditions: lung contusion, pneumothorax and haemothorax. The aim of this study was to evaluate the utility of arterial blood gas analysis parameters in predicting lung injury in blunt chest trauma.

we included 51 patients presenting to the Emergency Department of "C.T.O." Hospital in Naples [Italy] for blunt chest trauma. The patients were assigned to the Lung Injury Group or to the Non-Lung Injury Group basing on CT scan findings. For each patient, we calculated the alveolar-arterial oxygen gradient [AaDO₂], the AaDO₂ augmentation, the arterial partial pressure of oxygen deficit [PaO₂ Deficit] and the ratio between arterial partial pressure of oxygen and fraction of inspired oxygen [P/F]. Areas under the curve [AUC] and receiver operating characteristic [ROC] curve were used to compare the performance of each different test in relation to the detection of lung injury in blunt chest trauma.

patients with lung injury had lower oxygen saturation, arterial partial pressure of oxygen, P/F and higher PaO₂ Deficit, AaDO₂, AaDO₂ augmentation than patients without lung injury. PaO₂ Deficit, AaDO₂ and AaDO₂ augmentation showed a good accuracy to predict lung injury in blunt chest trauma.

our study demonstrates that the combination of different arterial blood gas analysis variables may be a fast approach for identifying patients with lung injury in the setting of blunt chest trauma in the Emergency Department.