(See also Overview of Thoracic Trauma Overview of Thoracic Trauma Thoracic trauma causes about 25% of traumatic deaths in the US. Many chest injuries cause death during the first minutes or hours after trauma; they can frequently be treated at the bedside... read more .)
The usual cause of hemothorax is laceration of the lung, intercostal vessel, or an internal mammary artery. It can result from penetrating or blunt trauma. Hemothorax is often accompanied by pneumothorax Pneumothorax Pneumothorax is air in the pleural space causing partial or complete lung collapse. Pneumothorax can occur spontaneously or result from trauma or medical procedures. Diagnosis is based on clinical... read more 
(hemopneumothorax).
Hemorrhage volume ranges from minimal to massive. Massive hemothorax is most often defined as rapid accumulation of ≥ 1000 mL of blood. Shock Shock Shock is a state of organ hypoperfusion with resultant cellular dysfunction and death. Mechanisms may involve decreased circulating volume, decreased cardiac output, and vasodilation, sometimes... read more is common.
Patients with large hemorrhage volume are often dyspneic and have decreased breath sounds and dullness to percussion (often difficult to appreciate during initial evaluation of patients with multiple injuries). Findings may be unremarkable in patients with smaller hemothoraces.
Diagnosis of Hemothorax
Chest x-ray
Sometimes E-FAST (Extended Focused Assessment With Sonography in Trauma)
Hemothorax is suspected based on symptoms and physical findings. Diagnosis is typically confirmed by chest x-ray and sometimes E-FAST or CT.
Treatment of Hemothorax
Fluid resuscitation as needed
Usually tube thoracostomy
Sometimes thoracotomy
Patients with signs of hypovolemia (eg, tachycardia, hypotension) are given IV crystalloid and sometimes blood transfusion (see Intravenous Fluid Resuscitation Intravenous Fluid Resuscitation Almost all circulatory shock states require large-volume IV fluid replacement, as does severe intravascular volume depletion (eg, due to diarrhea or heatstroke). Intravascular volume deficiency... read more ).
If blood volume is sufficient to be visible on chest x-ray (usually requiring about 500 mL), or if pneumothorax Pneumothorax Pneumothorax is air in the pleural space causing partial or complete lung collapse. Pneumothorax can occur spontaneously or result from trauma or medical procedures. Diagnosis is based on clinical... read more is present, a large-caliber (eg, 28 to 38 Fr) chest tube is inserted in the 5th or 6th intercostal space in the midaxillary line. Tube drainage improves ventilation, decreases risk of clotted hemothorax (which can lead to empyema or fibrothorax), and facilitates assessment of ongoing blood loss and diaphragmatic integrity. Blood collected via tube thoracostomy can be autotransfused, decreasing the requirement for crystalloid and exogenous blood.
Urgent thoracotomy is indicated in either of the following situations:
Initial bleeding is >1500 mL
Bleeding is > 200 mL/hour for > 2 to 4 hours and causes respiratory or hemodynamic compromise or the need for repeated blood transfusions.
