Clinical Significance and Prognostic Implications of Quantifying Pulmonary Contusion Volume in Patients with Blunt Chest Trauma

Background: Pulmonary contusion (PC) is the most frequent blunt chest injury which could be used to identify patients at high-risk of clinical deterioration. We aimed to investigate the clinical correlation between PC volume and outcome in patients with blunt chest trauma (BCT). Material/Methods: BCT patients with PC were identified retrospectively from the prospectively collected trauma registry database over a 2-year period. Contusion volume was measured and expressed as percentage of total lung (CTCV) volume using three-dimensional reconstruction of thoracic CT images on admission. Data included patients' demographics, mechanism of injury (MOI) and injury severity, associated injuries, CTCV, mechanical ventilation, complications, and mortality. Results: A total of 226 BCT patients were identified to have PC with a mean age of 35.2 years. Motor vehicle crash (54.4%) and falls (16.4%) were the most frequent MOIs. Bilateral PC (61.5%) was more prevalent than rightsided (19.5%) and left-sided PC (19%). CTCV had a significant positive correlation with ISS; whereas, age and PaO2/FiO2 ratio showed a negative correlation (p<0.05 for all). The median CTCV was significantly higher in patients who developed in-hospital complications (p=0.02). A CTCV >20% was associated with increasedrisk of acute respiratory distress syndrome (ARDS), blood transfusion and prolonged mechanical ventilation. However, multiple linear regression analysis showed that CTCV alone was not an independent predictor of in-hospital outcomes. Presence of chest infection, CTCV, and Injury Severity Scores were predictors of ARDS. Conclusions: Quantifying pulmonary contusion volume could allow identification of patients at high-risk of ARDS. CTCV has a significant correlation with injury severity in patients with BCT. Further prospective studies are needed to address the validity of CTCV in the patients care.