Thoracic Trauma

Hemothorax and open pneumothorax

Recognizing hemothorax. Blood in the pleural space causes decreased breath sounds and dullness to percussion. An upright radiograph blunts the costophrenic angle once a few hundred milliliters collect, but a supine film shows only diffuse haze over the hemithorax and can hide a liter; eFAST and CT are more sensitive. Treatment is tube thoracostomy in the 4th–5th intercostal space between the anterior and midaxillary lines, passed over the superior border of the rib because the intercostal vein, artery, and nerve run in the groove beneath each rib. Small-bore catheters are increasingly used in stable patients.

Massive hemothorax versus tension pneumothorax. Both cause shock with absent breath sounds on one side; the bedside examination separates them.

When to operate. Most hemothoraces stop bleeding once the lung re-expands. Operative thoracotomy is indicated for large initial output, continued brisk drainage, or persistent instability or transfusion dependence despite resuscitation.

Retained hemothorax. Clot that persists on imaging after chest tube drainage should be evacuated by video-assisted thoracoscopic surgery (VATS) within about 3–5 days, before it organizes. Left behind, it becomes empyema or fibrothorax with trapped lung, and a second chest tube rarely clears it.

Open pneumothorax. A chest-wall defect about two-thirds the diameter of the trachea or larger lets air enter through the wound instead of the airway, collapsing the lung with each breath. Cover it with a sterile occlusive dressing taped on three sides — a flutter valve that seals on inspiration and vents on expiration — then place a chest tube through a separate incision and close the wound surgically.

Taping the dressing on all four sides without a chest tube traps air and can create a tension pneumothorax.

Chest wall injury and pulmonary contusion

Flail chest. When two or more adjacent ribs each break in two or more places, the free segment moves paradoxically — inward on inspiration, outward on expiration. The paradox is rarely the main problem: hypoxemia comes chiefly from the underlying pulmonary contusion and from pain-driven splinting and hypoventilation. Positive-pressure ventilation eliminates the paradox but is reserved for respiratory failure.

Pulmonary contusion. Hemorrhage and edema in the lung beneath the impact cause shunting and hypoxemia. The first radiograph may be clear; patchy opacities that ignore lobar borders appear within about 6 hours, peak at 24–48 hours, and resolve over 3–7 days unless pneumonia or ARDS follows. CT is more sensitive. Care is supportive: oxygen, analgesia, pulmonary toilet, and judicious fluids to keep the patient euvolemic, because overload worsens the capillary leak. Corticosteroids and prophylactic antibiotics have no role.

Rib fractures in older adults. Patients 65 and older tolerate rib fractures poorly: each additional fractured rib raises mortality by roughly 19% and pneumonia risk by roughly 27%. Admit them, provide scheduled multimodal and regional analgesia, and keep a low threshold for ICU monitoring; splinting leads to atelectasis, pneumonia, and delayed respiratory failure.

Fracture location as a clue. Fractures of the first or second rib, scapula, or sternum mark a high-energy impact and prompt a search for great-vessel, brachial plexus, and cardiac injury. Lower rib fractures (9–12) point to the liver on the right, the spleen on the left, and the kidneys posteriorly. A child's compliant chest wall can transmit enough force to cause severe contusion without any rib fracture.

Blunt aortic and cardiac injury

Blunt aortic injury. Rapid deceleration (high-speed collision, fall from height) shears the aorta at the isthmus, just distal to the left subclavian artery where the ligamentum arteriosum tethers it. Roughly 80–85% of victims die at the scene; survivors have a hematoma contained only by adventitia that can rupture at any moment. Radiograph clues include:

• Mediastinum wider than 8 cm on a supine AP film and an obscured aortic knob
• Trachea and nasogastric tube deviated to the right; depressed left mainstem bronchus
• Left apical pleural cap and left hemothorax
• First- or second-rib fractures

Diagnosis and treatment. A normal radiograph does not exclude the injury, so mechanism alone justifies imaging. CT angiography of the chest is the test of choice; transesophageal echocardiography serves patients too unstable to leave the resuscitation bay or operating room. Start anti-impulse therapy with a short-acting β-blocker such as esmolol, targeting a heart rate below 80/min and systolic pressure near 100 mmHg, with good analgesia; add a vasodilator only after β-blockade so reflex tachycardia does not raise wall stress. Endovascular repair (TEVAR) has replaced open repair for most injuries and can wait until higher-priority hemorrhage is controlled; minimal intimal tears are followed with serial imaging.

Blunt cardiac injury. A direct anterior blow — classically the steering wheel — most often bruises the anteriorly placed right ventricle, and a sternal fracture is a clue. Screen with an ECG and troponin I. If both are normal, significant injury is excluded. A new arrhythmia, conduction block (often right bundle branch block), ST change, or elevated troponin calls for continuous telemetry for 24–48 hours; hemodynamic instability or a persistent arrhythmia calls for echocardiography to look for wall-motion abnormality, pericardial effusion, or valve or septal rupture. Sinus tachycardia is the most common rhythm abnormality.

Diaphragm and airway injuries

Diaphragmatic rupture. Blunt force produces large radial tears, usually on the left because the liver shields the right hemidiaphragm. The radiograph may show a nasogastric tube coiled above the left hemidiaphragm, bowel gas in the chest, or an elevated or indistinct left hemidiaphragm easily mistaken for hemothorax. CT can miss the defect, and negative intrathoracic pressure enlarges it over time, so herniation and strangulation may appear years later.

Repair. Every traumatic tear is repaired. Acute injuries are approached through the abdomen (laparotomy or laparoscopy) so associated intra-abdominal injuries can be treated; chronic hernias are often repaired through the chest because of adhesions.

Penetrating thoracoabdominal wounds. Wounds between the nipple line (the scapular tip posteriorly) and the costal margin can cross the diaphragm. In a stable patient with a left-sided wound and no peritonitis, diagnostic laparoscopy finds small defects that examination and CT miss.

Tracheobronchial injury. Most blunt airway injuries lie within 2.5 cm of the carina. Suspect one when a pneumothorax has a continuous large air leak or the lung fails to re-expand despite a working chest tube, especially with hemoptysis, pneumomediastinum, or spreading subcutaneous emphysema. The collapsed lung may sag away from the hilum toward the dependent chest (fallen lung sign). Bronchoscopy confirms the injury. Secure the airway with fiberoptic intubation beyond the tear or selective intubation of the opposite mainstem bronchus, add a second chest tube if needed, and repair significant tears operatively.

Emergency department thoracotomy

Who benefits. Resuscitative thoracotomy has its best results after penetrating chest trauma, especially stab wounds of the heart with tamponade; survival after blunt arrest is rare. Signs of life include pupillary response, respiratory effort, spontaneous movement, and organized cardiac electrical activity.

Technique and goals. A left anterolateral thoracotomy through the 5th intercostal space, extended across the sternum (clamshell) when needed, lets the team open the pericardium anterior to the phrenic nerve to release tamponade, control cardiac or lung hemorrhage, cross-clamp the descending aorta to divert blood to the heart and brain, evacuate air embolism, and perform internal cardiac massage. Patients who regain a pulse go directly to the operating room.