A 46-year-old restrained male driver involved in a high-speed head-on collision presented with hemodynamic instability (systolic blood pressure = 90 mm Hg, heart rate = 139 beats/min) following prehospital intubation for hypoxia. Extensive bruising to the patient's left hemithorax with a large flail segment and subcutaneous emphysema were noted. His trachea was midline with reported bilateral equal breath sounds on auscultation. Bilateral tube thoracostomy was performed. Despite aggressive fluid resuscitation, the patient remained transiently hemodynamically unstable. Although the initial supine anteroposterior chest radiograph displayed a mild rightward mediastinal shift, there was no evidence of an overt residual pneumothorax (Figure 1). The focused assessment with sonography for trauma examination also identified a small amount of perisplenic fluid concurrent to a normal pericardial space.