Emergency Medicine · Trauma
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Most commonly caused by blunt or penetrating chest trauma lacerating lung parenchyma or intercostal vessels.
Presents with dyspnea, decreased breath sounds, and stony dullness to percussion on the affected side.
Confirmed when pleural fluid hematocrit is ≥50% of serum hematocrit, distinguishing it from a simple effusion.
First-line treatment is a large-bore tube thoracostomy (32-36 French) in the 5th intercostal space at the mid-axillary line.
Emergent thoracotomy is indicated for initial output ≥1500 mL or ongoing bleeding ≥200 mL/hr for 2-4 hours.
Unlike tension pneumothorax (hyperresonant), massive hemothorax is dull to percussion though both can cause tracheal deviation.
Retained blood organizes into a restrictive fibrothorax or empyema if not adequately drained.
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A 24-year-old man is brought to the emergency department after a stabbing to the left chest. He is dyspneic and diaphoretic with a blood pressure of 88/54 mm Hg and a heart rate of 124/min. Breath sounds are absent over the left hemithorax with dullness to percussion. Upright chest radiograph shows blunting of the left costophrenic angle with a fluid level.
Which of the following is the most appropriate next step in management?
Placement of a large-bore (32-36 French) tube thoracostomy.
Tube thoracostomy both evacuates the hemothorax and quantifies ongoing blood loss to guide the need for thoracotomy. Dullness to percussion distinguishes hemothorax from a hyperresonant tension pneumothorax, and immediate output of 1500 mL or more would mandate operative exploration.
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Etiology / Epidemiology
Most commonly caused by blunt or penetrating chest trauma lacerating lung parenchyma or intercostal vessels.
Clinical Manifestations
Presents with dyspnea, pleuritic chest pain, and decreased breath sounds with stony dullness to percussion on the affected side.
Diagnosis
Diagnosed via upright chest X-ray showing blunting of the costophrenic angle; confirmed by pleural fluid hematocrit ≥ 50% of serum hematocrit.
Treatment
First-line treatment is large-bore tube thoracostomy (32-36 French); massive hemothorax requires emergent thoracotomy.
Prognosis
Complications include hypovolemic shock, retained clotted hemothorax, and restrictive fibrothorax or empyema
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Epidemiology & Etiology
Predominantly occurs secondary to thoracic trauma (motor vehicle collisions, stab/gunshot wounds). Non-traumatic spontaneous hemothorax is rare but includes bleeding diatheses, malignancies, or fatal complications of thoracic aortic dissection. Iatrogenic causes include central line placement, thoracentesis, or pleural biopsy.
Pertinent Anatomy
The pleural space lies between the parietal and visceral pleura, capable of holding up to 3 liters of blood per hemithorax, leading to exsanguination without major external bleeding. Bleeding typically originates from the low-pressure pulmonary parenchyma or high-pressure intercostal and internal mammary arteries via laceration.
Pathophysiology
Accumulation of blood in the pleural space compresses the ipsilateral lung parenchyma, leading to alveolar collapse and ventilation-perfusion (V/Q) mismatch. Large volumes of blood cause mediastinal shift, impeding venous return and decreasing cardiac output. The blood initially remains liquid due to mechanical defibrination by cardiac and respiratory movements, but may eventually clot and organize into a restrictive fibrothorax.
Clinical Manifestations
Patients present with sudden-onset dyspnea, chest pain, and signs of hypovolemic shock (tachycardia, hypotension, pallor). Physical exam reveals decreased or absent breath sounds and stony dullness to percussion over the affected hemithorax. Unlike tension pneumothorax which is hyperresonant, massive hemothorax presents with dullness, though both can exhibit tracheal deviation to the contralateral side.
Diagnosis
Upright chest radiograph is the initial test, requiring at least 200-300 mL of fluid to visualize blunting of the costophrenic angle or a classic meniscus sign. Bedside eFAST ultrasound rapidly detects fluid in the pleural cavity in trauma settings, preventing delayed recognition. Definitive diagnosis requires pleural fluid analysis demonstrating a pleural fluid hematocrit ≥ 50% of the peripheral serum hematocrit.
Treatment
Initial management requires ABCs, massive transfusion protocol if in shock, and large-bore tube thoracostomy (32-36 French) placed in the 5th intercostal space at the mid-axillary line. Emergent thoracotomy is indicated for massive hemothorax, strictly defined as initial chest tube output ≥ 1500 mL or continuous bleeding of ≥ 200 mL/hr for 2-4 hours. Prophylactic antibiotics like cefazolin are often administered for penetrating trauma to prevent secondary infection.
Prognosis
Failure to fully evacuate blood can lead to a retained hemothorax, requiring Video-Assisted Thoracoscopic Surgery (VATS) for definitive evacuation. Untreated retained blood significantly increases the risk of empyema and late restrictive lung disease from fibrothorax. Patients require close hemodynamic monitoring for rebleeding and serial chest imaging to ensure complete lung re-expansion.
Differential Diagnosis
1. Tension Pneumothorax: Presents with tracheal deviation and shock but has hyperresonance to percussion instead of dullness.
2. Pleural Effusion: Accumulation of transudative or exudative fluid rather than blood; pleural fluid hematocrit is strictly < 50% of serum.
3. Cardiac Tamponade: Trauma patient with shock and Beck's triad (hypotension, JVD, muffled heart sounds) but a normal pulmonary exam.
4. Pulmonary Contusion: Blunt trauma causing alveolar hemorrhage, presenting with focal crackles and patchy opacities on imaging without a distinct fluid level.