What is a Hemothorax and What are the Causes?

Definition, Causes, and Treatment of Hemothorax

lateral chest x-ray
What is a hemothorax and what are the causes?. Flickr.com/Creative Commons/Fourrure

If you've been told that you or a loved one have a hemothorax, you are probably very frightened. What is a hemothorax, what are some of the causes, and how are they treated?

What is a Hemothorax?

A hemothorax is defined as the accumulation of blood between the membranes lining the lungs (the pleura). Depending upon the cause, the blood may originate from the lungs, the hearts, the chest wall, or the large blood vessels present in the chest.

It's thought that close to 300,000 cases of hemothorax occur in the United States each year due to trauma alone, with chest injuries present in roughly 60 percent of patients with multiple trauma injuries.

Causes of a Hemothorax

There are many possible causes of a hemothorax. Some of these include:

  • Trauma to the chest is the most common cause of a hemothorax.
  • Emphysema.
  • Lung cancer, mesothelioma, and cancers that are metastatic (spread) to the lung.
  • Chest surgery (most commonly lung and heart surgery.)
  • Biopsy of lung masses.
  • Lung infections such as tuberculosis.
  • Bleeding disorders that result in prolonged clotting.
  • Pulmonary embolism and infarcts.

Hemothorax Symptoms

Symptoms may include:

  • Severe shortness of breath.
  • Anxiety and extreme restlessness.
  • Symptoms of shock such as a rapid heart rate, low blood pressure, pale, cold extremities and weakness.
  • Chest pain which is often sharp and may vary with position.

    Workup and Evaluation

    A careful history may give some clues to the cause and presence of a hemothorax—such as chest trauma or chest surgery. On the side affected, lung sounds may be diminished or absent. An upright chest x-ray may help to diagnose a hemothorax, and further testing, such as a chest CT may then be considered.

    When the chest tube is placed, the fluid may be evaluated to confirm the presence of blood in the pleural cavity and further look for possible causes.

    Evaluation of the pleural fluid can be helpful as well. For this fluid to be classified as a hemothorax, the hematocrit of the pleural fluid should be at least 50 percent of the hematocrit of the peripheral blood - blood examined by taking a sample from a vein.

    Hemothorax Treatment

    Initial treatment for a hemothorax usually involves stabilizing the patient and then inserting a chest tube to drain the blood and air that has built up or is building up between the lung membranes in the pleural cavity.

    Often, a hemothorax is a result of blunt or penetrating trauma to the chest. When it occurs without trauma, it's very important to determine and treat the underlying cause.

    For some people surgery, a thoracotomy is needed to get to the source and control the bleeding.

    Complications of a Hemothorax

    For those people who receive treatment, a small number are left with an empyema (a collection of pus between the membranes lining the lungs) or some scarring of the pleura (pleural fibrosis).

    Fibrosis may result in long-term respiratory symptoms for some people. With an empyema, further surgeries may be done to remove the pus and to prevent further fluid and bacteria from entering the chest. Treatments for fibrosis are primarily supportive as fibrosis is usually irreversible. That said, treatments ranging from pulmonary rehabilitation to breath training can be helpful in restoring the best quality of life possible.


    The outcome of a hemothorax is determined by both the extent of the bleeding, and the underlying cause. For people who sustain a hemothorax as a result of chest trauma, the overall prognosis is actually quite good, and excellent if the hemothorax can be adequately treated.


    Aktas, A. et al. Transthoracic biopsy of lung masses: Non technical factors affecting complication occurrence. Thoracic Cancer. 2015. 6(2):151-8.

    Broderick, S. Hemothorax: Etiology, diagnosis, and management. Thoracic Surgery Clinics. 2013. 23(1):89-96.

    Mancini, M et al. Hemothorax. Medscape. Updated 10/15/14.

    Morgan, C., Bashoura, L., Balachndran, D., and A. Saadia. Spontaneous Hemothorax. Annals of the American Thoracic Society. 2015. 12(10):1578-1582.

    Patrini, D. et al. Etiology and management of spontaneous haemothorax. Journal of Thoracic Disease. 2015. 7(3):520-6.

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