Overview:
Barotrauma is a traumatic change caused due to an alteration in the water or air pressure. It is common in scuba divers and people who travel in jets. Barotrauma is damage caused to the body tissues physically. It happens due to a pressure difference between the gaseous space inside the body and the surrounding external environment. If the condition of barotrauma affects the entire body, then it is called generalized barotrauma or decompression sickness.
Pulmonary barotrauma is a common condition. It occurs due to an invasive mechanical ventilation procedure that leads to alveolar rupture. In this way, the tissues in the lungs get disrupted. Barotrauma can happen due to the increase in trans alveolar pressure. Air leaks into extra-alveolar tissue resulting in conditions such as pneumothorax, pneumomediastinum, pneumoperitoneum, and subcutaneous emphysema.
What Is Epidemiology?
The incidence of barotrauma during a mechanical ventilation procedure differs based on the underlying indication for mechanical ventilation. The incidence, in this case, ranges from 0 to 50 percent. The recent advancements in the mid-2000s have led to the application of low tidal volume ventilation. With this advancement, the rate has reduced so well in a range of more than 10 percent than the earlier time.
What Causes Barotrauma?
Barotrauma mainly occurs due to two reasons. It includes either the rupture of the alveoli of the lungs, or it involves a direct injury. Alveolar rupture is of two types. They are ventilator-related or disease-related. The following are the various causes of ventilator-related alveolar rupture.
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Positive Pressure Ventilation: A normal breathing cycle is chiefly dependent on the negative pressure inside the lungs compared to the pressure of the external atmosphere. However, mechanical ventilators usually deliver a positive influence. Positive pressure ventilation causes an increase in pressure at the nearby regions of the alveolus. This increase in pressure finally leads to the rupture of the alveolar sac’s membrane.
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Elevated Pressure: A regular mechanical ventilator is inserted into a patient. Increased pressure in the ventilator can injure the alveolus and result in barotrauma.
The cause for the disease-related type is not known fully.
What Are the Risk Factors?
Certain diseases serve as a risk factor for a patient to acquire barotrauma when they are intubated with a mechanical ventilator. Those diseases are as follows:
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Chronic interstitial lung disease.
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Acute respiratory distress syndrome.
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Direct mechanical injury to the alveolus due to any external cause may lead to an escape of the air to the surrounding tissue such as the pleura, accessory respiratory muscles. These injuries also can cause conditions that are similar to barotrauma.
What Is the Pathophysiology of Barotrauma and Mechanical Ventilation?
The exact pathophysiology that accounts for lung injury and barotrauma in mechanically ventilated patients remains unclear. However, research evidence has shown that increased inflation or air swelling and increased pressure on the alveolar membranes can lead to inflammatory changes. The inflammatory change causes a rupture and leakage of air into the external alveolar tissues. This can further lead to complications like pneumothorax or infections.
Usually, an increase in pressure was very significant to approach and treat patients who required mechanical ventilation to support their normal breathing. This was done to minimize the risk of atelectasis. It refers to the condition where there is a collapse of the alveolar sacs and ventilation. Such ventilatory settings lead to high inspiratory pressures where the patient is mechanically set to inhale air with increased pressure. It results in increased inflation of the alveolar unit.
Hyperinflation is very commonly seen in patients with acute respiratory distress syndrome (ARDS) and other types of lung diseases. Normal alveoli usually receive a comparatively increased percentage of air pressure, which causes preferential ventilation. Finally, it leads to hyperinflation to accommodate the larger tidal volume, which results in barotrauma of the lungs.
What Is Ear Barotrauma?
Ear barotrauma is an injury to the ear, which is caused by any instant changes in pressure. It can also be caused by other circumstances, such as sea diving. This adventurous sport can affect people with respiratory conditions such as nasal stuffiness or others. Barotraumas occur in several different types and can contribute to the most common scuba-diving injuries. Middle-ear barotrauma occurs mostly in first-time divers. It affects a small population of experienced divers also. Injuries of this type can be very serious. It may even result in permanent hearing loss, which is accompanied by excruciating pain. It can be cured after two weeks. Some severe cases of barotrauma keep divers out of the water for many months. It is always easy to prevent ear barotrauma if people follow the proper precautions. One of the primary preventative measures is to avoid scuba-diving if you have an ongoing respiratory problem.
What Is Airplane Ear?
An airplane ear is a type of ear barotrauma. It is defined as stress on a person’s eardrum that occurs when the air pressure in his or her middle ear and the air pressure in the environment fail to balance. A person might get affected by an airplane ear when he or she is on an airplane, especially when the airplane is in takeoff or landing.
Airplane ears are also termed ear barotrauma, parotitis media, or aerotitis media. Self-care measures such as yawning, swallowing, and chewing gum casually can prevent this condition.
How Is Barotrauma Managed Initially?
Once pulmonary barotrauma secondary to the mechanical ventilator is suspected in an intubated patient, necessary action must be taken immediately. The physical exam will be remarkable for absent breath sounds, and in most cases, patients who can communicate will complain of symptoms such as shortness of breath and chest pain.
Vital signs usually show a decrease in oxygen saturation. Hypotension occurs secondary to obstructive shock in a patient affected with tension pneumothorax. In patients who develop a tension pneumothorax, the necessary action is taken even before diagnosing with a chest radiograph. Tension pneumothorax patients would need urgent needle decompression to evacuate the pneumothorax presented. The placement of a thoracostomy tube would follow that.
In patients presenting with relatively minor complications, like pneumothorax with stable oxygen saturation and heart rate, the clinician should first check a chest radiograph. The chest radiograph is a vital tool to identify pneumothorax, pneumomediastinum, subcutaneous emphysema, and less common manifestations of pulmonary barotrauma.
How Is It Diagnosed?
The diagnosis of barotrauma would usually require the following;
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Medical history of the patient.
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Chest imaging and computed tomography (CT) scan of the chest. A chest X-ray is usually done to check for signs of pneumothorax or pneumomediastinum. If the chest X-ray is negative, but there is strong clinical suspicion of barotrauma, then chest CT, which is more sensitive than X-rays, may be used as a diagnostic tool.
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A neurologic examination for signs of brain dysfunction due to arterial gas embolism.
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Ultrasound is also very useful for faster bedside diagnosis of pneumothorax.
What Is the Treatment Option?
There is no single way to prevent pulmonary barotrauma occurrence in patients who are in mechanical ventilation support. The most efficient way of management that has been described to prevent the risk of developing barotrauma on mechanical ventilation involves the maintenance of the plateau and peak inspiratory pressures.
Different ventilator modes are available right now. The most commonly used methods in intensive care units are volume assist control (volume AC), a volume cycled mode, and pressure assist control (pressure AC), a pressure cycled mode.
Conclusion:
Prevention of pulmonary barotrauma is always the priority. Patients who are at high risk should never dive into areas with compressed air. Patients with asthma are very commonly at risk of pulmonary barotrauma. It is necessary to get medical clearance before diving. Feel free to get help from our online platform.
