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Pulmonary Barotrauma

By

Richard E. Moon

, MD, Duke University Medical Center

Last full review/revision Jun 2021| Content last modified Jun 2021
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Barotrauma is tissue injury caused by a pressure-related change in body compartment gas volume. Factors increasing risk of pulmonary barotrauma include certain behaviors (eg, rapid ascent, breath-holding, breathing compressed air) and lung disorders (eg, COPD [chronic obstructive pulmonary disease]). Pneumothorax and pneumomediastinum are common manifestations. Patients require neurologic examination and chest imaging. Pneumothorax is treated. Prevention involves decreasing risky behaviors and counseling high-risk divers.

Overexpansion and alveolar rupture can occur when breath-holding occurs (usually while breathing compressed air) during ascent, particularly rapid ascent. The result can be

Pneumomediastinum may also cause crepitation in the neck, due to associated subcutaneous emphysema, and a crackling sound may rarely be heard over the heart during systole (Hamman sign). Air can sometimes track caudad into the peritoneal cavity (falsely suggesting a ruptured viscus and the need for laparotomy), but it does not typically cause peritoneal signs.

Alveolar rupture can allow air into the pulmonary venous circulation with subsequent arterial gas embolism Arterial Gas Embolism Arterial gas embolism is a potentially catastrophic event that occurs when gas bubbles enter or form in the arterial vasculature and occlude blood flow, causing organ ischemia. Arterial gas... read more , which is particularly dangerous when it involves the brain, but can also affect other organs (eg, spinal cord, heart, skin, kidneys, spleen, gastrointestinal tract).

Compression of the lungs may occur during very deep descent in breath-hold diving; compression may rarely decrease lung volume below residual volume, causing mucosal edema, vascular engorgement, pulmonary edema, and hemorrhage, which manifest clinically as dyspnea and hemoptysis on ascent.

Diagnosis

  • Chest imaging

Chest x-ray is done to look for signs of pneumothorax or pneumomediastinum (radiolucent band along the cardiac border). If chest x-ray is negative but there is strong clinical suspicion, then chest CT, which may be more sensitive than plain film x-rays, may be diagnostic. Ultrasound may also be useful for rapid bedside diagnosis of pneumothorax. Pneumoperitoneum without a ruptured viscus should be suspected when pneumoperitoneum is present without peritoneal signs.

If patients have any neurologic deficits found on neurologic examination, arterial gas embolism to the brain should be suspected.

Treatment

  • 100% oxygen

  • Sometimes tube thoracostomy

Suspected tension pneumothorax is treated with needle decompression followed by tube thoracostomy How To Do Surgical Tube Thoracostomy Surgical tube thoracostomy is insertion of a surgical tube into the pleural space to drain air or fluid from the chest. Pneumothorax that is recurrent, persistent, traumatic, large, under tension... read more How To Do Surgical Tube Thoracostomy . If a smaller (eg, 10 to 20%) pneumothorax is present and there is no sign of hemodynamic or respiratory instability, the pneumothorax may resolve when high-flow 100% oxygen is given for 24 to 48 hours. If this treatment is ineffective or if a larger pneumothorax is present, tube thoracostomy (using a pigtail catheter or small chest tube) is done.

No specific treatment is required for pneumomediastinum; symptoms usually resolve spontaneously within hours to days. After a few hours of observation, most patients can be treated as outpatients; high-flow 100% oxygen is recommended to hasten resorption of extra-alveolar gas in these patients. Rarely, mediastinotomy Mediastinoscopy and Mediastinotomy Mediastinoscopy is a procedure in which an endoscope is introduced through the suprasternal notch into the mediastinum to allow visualization of it. Mediastinotomy is surgical opening of the... read more is required to relieve tension pneumomediastinum.

Prevention

Prevention of pulmonary barotrauma is usually the top priority. Proper ascent timing and techniques are essential. Patients at high risk for 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 Pneumothorax during diving include those with pulmonary bullae, Marfan syndrome Marfan Syndrome Marfan syndrome consists of connective tissue anomalies resulting in ocular, skeletal, and cardiovascular abnormalities (eg, dilation of ascending aorta, which can lead to aortic dissection)... read more Marfan Syndrome , chronic obstructive pulmonary disease Chronic Obstructive Pulmonary Disease (COPD) Chronic obstructive pulmonary disease (COPD) is airflow limitation caused by an inflammatory response to inhaled toxins, often cigarette smoke. Alpha-1 antitrypsin deficiency and various occupational... read more Chronic Obstructive Pulmonary Disease (COPD) , or previous spontaneous pneumothorax. Such individuals should not dive or work in areas of compressed air. Patients with asthma Asthma Asthma is a disease of diffuse airway inflammation caused by a variety of triggering stimuli resulting in partially or completely reversible bronchoconstriction. Symptoms and signs include dyspnea... read more may be at risk of pulmonary barotrauma, although many people with asthma can dive safely after they are evaluated and treated appropriately. Patients with pneumomediastinum Pneumomediastinum Pneumomediastinum is air in mediastinal interstices. The main causes of pneumomediastinum are Alveolar rupture with dissection of air into the interstitium of the lung with translocation to... read more Pneumomediastinum after a dive should be referred to a diving medicine specialist for assessment of risks of future dives.

Key Points

  • Although rare, pulmonary barotrauma can result in tension pneumothorax, which must be immediately decompressed.

  • Examine all patients who have pulmonary barotrauma for signs of brain dysfunction, which suggests arterial gas embolism.

  • Treat all patients with suspected pulmonary barotrauma with 100% oxygen pending diagnostic testing.

More Information

The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

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