Open Pneumothorax · What Is It, Diagnosis, and More

An open pneumothorax and a closed pneumothorax are both types of pneumothorax, the difference between them is how air gets into the pleural cavity.  

An open pneumothorax occurs when an injury creates a hole in the chest wall that allows air from the environment to enter the pleural cavity. The most common cause is a penetrating chest injury, such as that from a stab wound or gunshot wound. On the other hand, a closed pneumothorax occurs when air leaks from the lung into the pleural space, but the chest wall remains intact. 

A lung disease, such as chronic obstructive pulmonary disease (COPD), cystic fibrosis, lung cancer, or pneumonia, can be the source of a closed pneumothorax. However, damage can also occur spontaneously in predisposed individuals, a phenomenon called spontaneous pneumothorax. 

An open pneumothorax is often due to forceful impact with a dull object penetrating trauma to the chest wall. Blunt or penetrating trauma can happen in situations such as physical attacks, falls, or motor vehicle accidents.  

In addition, an open pneumothorax may be iatrogenic, meaning it’s a result of a diagnostic procedure or treatment. For example, a clinician could unintentionally injure the chest wall during a transtracheal aspiration, a procedure that requires inserting a needle into the lung tissue; a lung biopsy, in which a portion of the lung tissue is removed; or during a tube thoracostomy, where a tube is placed in the pleural cavity.  

The signs and symptoms of an open pneumothorax include sudden chest pain, shortness of breath, rapid and shallow breathing, a fast heart rate, and low oxygenation of body tissues, called hypoxia. Sometimes, individuals with this condition may feel weak, dizzy, restless, or agitated. An open chest wound may be visible, or a sucking sound may be audible when air enters the wound.  

With each breath, air moves freely in and out of the pleural space through the chest wall defect, preventing expansion of the lungs. If air continues to enter the pleural space without being able to escape, the individual may develop a tension pneumothorax. As a result of the rising pressure in the pleural space, the lung collapses and pushes the mediastinum to the opposite side, compressing the heart and the other lung. If left untreated, tension pneumothorax can lead to cardiovascular collapse and cardiac arrest.  

An open pneumothorax is usually first diagnosed clinically, especially in trauma settings and then confirmed with imaging. Common examination findings include shallow and rapid breathing and decreased or absent breath sounds on the affected side of the chest.  

Imaging can also assist in diagnosis; the extended focused abdominal sonography for trauma (E-FAST) exam is a diagnostic tool that can be performed rapidly in trauma settings and doesn’t delay initiation of treatment. Computerized tomography (CT) and chest X-ray are also options, although an ultrasound is typically more useful than a chest X-ray as it allows detection of smaller pneumothoraxes. If a patient is unstable with a suspected open pneumothorax, treatment is typically initiated before imaging is used to confirm the diagnosis.  

Emergency management of an open pneumothorax involves covering the wound with an occlusive dressing taped on three sides only. This allows air to escape but not re-enter during inspiration, functioning as a one-way valve. If the dressing is not properly applied, and it allows air into the chest space without allowing it to escape, a tension pneumothorax may develop.   

After stabilization, a chest tube may be inserted into the chest wall, typically into the left fifth intercostal space, mid-axillary line. Supplemental oxygen may be required if hypoxia is severe. Long-term treatment involves surgical intervention to repair the open wound or defect in the chest.