Extended focused assessment with sonography in trauma injury pattern associations in blunt versus penetrating trauma

Background Extended focused assessment with ultrasound for trauma (EFAST) is a key component in the assessment of trauma patients; however, there is a paucity of research regarding how injury patterns manifest in EFAST and how associations might differ in blunt versus penetrating trauma.Methods A retrospective review was conducted of EFAST studies at a level 1 trauma center, capturing 1356 EFAST exams. Chi-squared analysis was used to evaluate associations within trauma groups and to compare injury prevalence between trauma subgroups.Results Among all ultrasound exams, 34 (2.5%) had pneumothorax, 23 (1.6%) had pericardial fluid, and 63 (4.6%) had intra-abdominal fluid. In the blunt trauma subgroup, 29 (2.4%) had pneumothorax, 19 (1.6%) had pericardial fluid, and 50 (4.2%) had intra-abdominal fluid. In the penetrating trauma subgroup, 5 (4.9%) had pneumothorax, 1 (1%) had pericardial fluid, and 11 (10.8%) had intra-abdominal fluid. Pneumothorax was associated with intra-abdominal fluid across all scans (P = 0.03). Within the penetrating trauma subgroup specifically, intra-abdominal fluid was associated with pericardial fluid (P = 0.004), and intra-abdominal fluid was more likely to be present compared to the blunt trauma subgroup (P = 0.003). Pneumothorax and pericardial effusion incidence did not differ between trauma categories.Conclusions The strong association of pneumothorax with intra-abdominal fluid, and intra-abdominal fluid with pericardial fluid, underscores the critical role of a complete EFAST in trauma evaluation, particularly once evidence of injury in one of these anatomic regions is identified.