2: Thoracic Trauma

Epidemiology

• Twenty percent of all trauma patients sustain chest injuries.

Pathophysiology

• Thoracic injuries, like with all traumas, can result from blunt or penetrating mechanism. Fractures and soft tissue injuries are common. Compromised breathing remains a particularly urgent concern in these patients, which is unique to thoracic injuries and demonstrates common physiologic signs regardless of cause. Structures that can be injured include the protective bony thorax (ribs, sternum, scapula, and spinal column). The diaphragm inferiorly, and the soft tissue content of the thorax (heart, lungs, esophagus, and great vessels). Severe cardiovascular compromise can also result from injury to the chest.

Clinical features

• Outside of the pain of injury, obvious clinical compromise that results from thoracic injury includes primarily signs of respiratory embarrassment and hemodynamic instability. Presenting symptoms vary according to the injured structure. Potential symptoms include dyspnea, tachypnea, and pain on palpation. Signs include contusions, penetrating wounds, subcutaneous emphysema, crepitance, distant or unequal breath sounds on auscultation, muffled heart sounds, tracheal deviation, jugular venous distension, absent upper extremity pulses, shock, and distal neurologic deficit.

Diagnostics

• Physical examination including vital signs as part of the primary survey remains the initial most important diagnostic evaluation. Chest x-ray, upright where possible, is desirable. This will delineate injury to most bony structures, identify hemopneumothoraces, raise suspicion about mediastinal injury, and potentially aid in determination of trajectory of penetrating injuries. The patient’s hemodynamic status and mechanism of injury guide further diagnostic workup. Focused assessment with sonography for trauma (FAST) ultrasound can identify presence of fluid or the absence thereof in the pericardial sac. Thoracic computed tomography (CT) scan and CT angiography are valuable and reliable in assessing injuries to the great vessels in stable patients at risk and helpful in determining at-risk structures given the trajectory of the penetrating injury. Esophagoscopy, bronchoscopy, and esophagography all play a role in assessing the integrity of these structures and identifying the need for operative repair. In some situations, diagnosis is made necessarily at the time of therapeutic intervention as in the placement of a chest tube for signs of a tension pneumothorax, relief of pericardial tamponade via an emergency department (ED) thoracotomy in an arrested patient, or pericardial window at laparotomy.

Treatment

• As with all trauma patients, the best approach in management is delineated by ATLS guidelines. Addressing the need for a secure airway and ensuring adequate breathing and circulation necessitates rapid assessment of the thorax, diagnosis, and intervention for life-threatening abnormalities. Further management depends on structure-specific injuries.

Outcomes

• Outcomes for thoracic trauma are widely varied, are injury and mechanism dependent, and vary tremendously according to patient presentation and the specific structures that are injured.