Pneumothorax is the medical term commonly known as a lung collapsed with the presence of air or gas in the pleural cavity (Figures). When air leaks into the space between the lung and chest wall, a pneumothorax occurs. This air pushes out of your lung and causes it to collapse.
In most cases, only part of the lung collapses. It is quite common and has many different reasons. Pneumothorax can be caused by blunt or stab chest injury, some medical procedures, or damage from underlying lung disease. Or it can occur for no apparent reason.
Symptoms often include sudden chest pain and shortness of breath. In some cases, a collapsed lung can be a life-threatening event.
Clinical outcomes depend on the degree of collapse of the lung on the affected side. If pneumothorax is important, it may cause the mediastinum to shift and compromise hemodynamic stability.
If you have pneumothorax and think breathing is difficult, call your local emergency number for the ambulance.
There is no direct figure about the incidence of pneumothorax. However, it is often a common problem as a complication (often undiagnosed) of trauma and also occurs as a spontaneous formation and in patients with lung disease before.
A pneumothorax treatment usually involves inserting a flexible tube or needle between the ribs to remove excess air it contains. However, a small pneumothorax can heal on its own.
Lungs are cone-shaped, soft, spongy organs in the thoracic (chest) cavity (Figure). The lungs are largely made up of air tubes and cavities. The balance of the lung tissue, the stroma is a framework of connective tissue, which includes many elastic fibers. As a result, the lungs are light, soft, spongy, elastic organs, and each weigh only about 0.6 kg (1.25 pounds).
The flexibility of healthy lungs helps to reduce breathing effort.
The lungs are separated from each other by the heart and other structures of the mediastinum, which divides the thoracic cavity into two anatomically different chambers. As a result, if trauma causes one lung to collapse, the other may expand.
Each lung is closed and protected by a double-layer serous membrane called the pleural membrane or pleura. The superficial layer called the parietal pleura covers the wall of the thoracic cavity; deep layer, visceral pleura covers the lungs themselves. Between the visceral and the parietal pleura there is a small cavity, the pleural cavity, which contains a small amount of lubricating fluid secreted by the membranes.
This pleural fluid reduces friction between the membranes and allows them to slide easily on top of each other during breathing. Pleural fluid also causes two membranes to stick together, just like a water film causes two glass microscope slides, a phenomenon called surface tension, to stick together.
Separate pleural spaces surround the left and right lungs. The left and right lungs are located in the left and right pleural cavities inside the thoracic cavity.
If the air enters the pleural cavity, a condition called pneumothorax, the lung will collapse. The air breaks the seal of the pleural fluid that holds the lung to the thoracic wall, causing the elastic lung to collapse like a deflated balloon.
If inflammation continues, excess fluid accumulates in the pleural cavity, a condition known as pleural effusion.
Under the lungs, a thin, dome-shaped muscle called the diaphragm separates the chest from the abdomen. When you breathe, the diaphragm moves up and down, releasing air into and out of the lungs.
The rib cage surrounds the rest of the lungs.
Types of pneumothorax and their causes
The two main types of pneumothorax are traumatic pneumothorax and non–traumatic pneumothorax. If the air surrounding the lungs increases in pressure, both types can lead to a tension pneumothorax. Tension is common in cases of pneumothorax trauma and requires urgent medical treatment.
Traumatic pneumothorax occurs after some form of trauma or injury to the chest or lung wall. There may be a minor or major injury.
Trauma can damage the chest structures and cause air to leak into the pleural cavity.
Examples of injuries that can cause a traumatic pneumothorax include:
• trauma from motor vehicle accident to chest
• broken ribs
• a hard hit on the chest from a contact sport like a football team
• a knife or bullet wound on the chest
• medical procedures that may damage the lung, such as central line placement, ventilator use, lung biopsies, or CPR
Changes in air pressure caused by scuba diving or mountain climbing can also cause a traumatic pneumothorax. The altitude change can cause air bubbles to develop in your lungs and then rupture and collapse of the lungs.
Rapid treatment of pneumothorax is important due to significant chest trauma.
Symptoms are often severe and can contribute to potentially fatal complications such as cardiac arrest, respiratory failure, shock, and death.
This type of pneumothorax does not occur after injury. Instead, it happens spontaneously, so it is also called spontaneous pneumothorax.
There are two main types of spontaneous pneumothorax: primary and secondary.
Primary spontaneous pneumothorax (PSP) occurs in people without a known lung disease and often affects young men who are tall and weak (asthenic body posture).
Secondary spontaneous pneumothorax (SSP) tends to occur in older people with known lung problems.
Some situations that increase your risk of SSP include:
- Chronic obstructive pulmonary disease (COPD), such as emphysema or chronic bronchitis
- Acute or chronic infection, such as tuberculosis or pneumonia
- lung cancer
- Cystic fibrosis, a genetic lung disease that causes mucus to accumulate in the lungs
- asthma, a chronic obstructive airway disease that causes inflammation
Spontaneous hemopneumothorax (SHP) is a rare subtype of spontaneous pneumothorax. It occurs when both blood and air have recently filled the pleural cavity without a history of trauma or lung disease.
Progression of pneumothorax
Excluding caused by chest trauma, pneumothorax occurs due to rupture of the alveoli, followed by rupture of the pleural lining of the lung. If this communication then closes itself, the air in the pleural cavity is slowly absorbed. If communication between the pleural cavity and the airways remains open, a ‘bronchopleural fistula‘ is created.
Rarely, communication remains open, but the defect functions as a flap valve and supplies air to the pleural cavity during inspiration, but prevents it from escaping during expiration. Thus, with every breath, air accumulates in the pleural cavity, compresses the adjacent lung, and ultimately compresses other structures in the chest, including the heart. This is called “tension pneumothorax“. Tension pneumothorax rarely occurs spontaneously.
Many people who have had a pneumothorax can have another recurrence, usually within one to two years from the first. If the opening in the lung does not close, air may continue to leak. Surgery may eventually be required to close the air leak.
Causes of pneumothorax
A pneumothorax can cause:
- Chest injury. Any blunt or stab injury to your chest can cause lung collapse. Some injuries may occur during physical assault or car accidents, while others may accidentally occur during medical procedures involving inserting a needle into the chest.
- Lung disease. Damaged lung tissue is more likely to collapse. Lung damage can be caused by many underlying diseases, including chronic obstructive pulmonary disease (COPD), cystic fibrosis, and pneumonia.
- Explosed air bubbles. Small air bubbles (blebs) may develop on your lung. These blebs sometimes burst – allowing air to seep into the area surrounding the lungs.
- Mechanical ventilation. A serious type of pneumothorax may occur in people who need mechanical assistance to breathe. The ventilator may create an air pressure imbalance in the chest. The lung can collapse completely.
Risk factors for pneumothorax include:
- Your gender. In general, men are much more likely to have pneumothorax than women.
- To smoke. The risk increases with duration and number of cigarettes smoked, even without emphysema.
- Age. The type of pneumothorax caused by ruptured air bubbles occurs in people between the ages of 20 and 40, especially if the person is too tall and weak.
- Genetics. Some types of pneumothorax occur in families.
- Lung disease. Having an underlying lung disease, especially chronic obstructive pulmonary disease (COPD), makes a collapsed lung more likely.
- Mechanical ventilation. People who need mechanical ventilation to help them breathe are at higher risk of pneumothorax.
- Previous pneumothorax. Anyone who has had a pneumothorax is at greater risk for the other, usually within one to two years of the first.
Pneumotorax signs and symptoms
Pneumothorax is presented as asymptomatic and nonclinical signs or symptoms in a primary spontaneous pneumotorax, (a bleb rupture). Typically, the chest pain and difficulty in breathing are with especially with secondary spontaneous pneumotorax.
The tension pneumothorax presents with hypotension, hypoxia, and chest pain.
The catamenial pneumotorax: Catamenial pneumothorax is a condition of air leaking into the pleural space (pneumothorax) occurring in conjunction with menstrual periods (catamenial refers to menstruation), and or during ovulation, believed to be caused primarily by endometriosis of the pleura (the membrane surrounding the lung or diaphragm).
A chest X-ray selection test: small pneumotorax (less than 20% of the hemorahocxes) can be difficult to be seen in the chest x-ray; And a graphy, which is taken during the end of exhalation, can help visualize.
In some cases, a computerized tomography (CT) can be displayed to provide more detailed images. CT scanners combine images from many different directions to produce such as detailed images of internal structures.
The larger pneumotorax, the cause of the lung’s trachea and mediastinum (heart and large vessels) move away from the affected side (mediastinal shift)*.
Physical examination of a patient with a pneumotorax, a demonstration of decreased breath sounds at the affected side.
Symptoms might contain pleuritic pain, chest pain and difficulty in breathing. Affected patients may also show mental state changes, including decrease warning and / or conscious.
Treatment of pneumothorax
The purpose of a pneumothorax treatment is to relieve the pressure on your lungs and allow it to expand again. Depending on the cause of pneumothorax, a second goal may be to prevent relapses.
The methods of achieving these goals depend on the severity of lung collapse and sometimes your overall health.
Choosing from the various management options in pneumothorax requires an understanding of the natural history of pneumothorax, the risk of recurrent pneumothorax, and the benefits and limitations of treatment options. Oxygen-free observation, supplemental oxygen delivery, simple aspiration, chest tube placement, video-assisted thoracoscopic surgery (VATS), open thoracotomy and pleurodesis are among these options.
• Small pneumothorax may not require treatment. If only a small part of your lung collapses, your doctor can monitor your condition at 1-week intervals with a series of chest X-rays until excess air is completely absorbed and your lung re-expands. Normally this takes a week or two. It can speed up the process of supplemental oxygen absorption.
• The larger and tension pneumothorax requires air aspiration (needle inserted into the pleural cavity between the ribs) with the placement of the intercostal drainage tube shortly thereafter. This drain tube ends with an underwater seal; therefore, escaping air is seen as bubbles in the water, but air from the atmosphere cannot return.
Sometimes, pneumothorax continues to bubbling after a 5-7 days; this indicates the presence of bronchopleral fistula and surgery may be required. This involves either removing the pleura or sticking the two pleural layers together by placing them in the pleural cavity (talc pleurodesis).
• A tension pneumothorax should be treated immediately by *decompression with a needle in the 2nd intercostal space (between the second and third ribs in front). This is then followed by an official intercostal tube placement as above.
• Catamenial pneumothorax treatment includes hormonal therapy and surgical treatment (wedge lung resection, pleurectomy, chemical or mechanical pleurodesis and diaphragm reconstruction – using direct stitching or synthetic meshes). Video-assisted thoracoscopic surgery (VATS) is the preferred access in the treatment of pneumothorax. Thoracotomy is indicated only in cases of relapse after a previous procedure. If the procedure contains large lesions in the diaphragm, the use of video-assisted mini-thoracotomy is recommended. Most authors agree on the recommendations for bullectomy, pleurectomy, or pleurodesis.
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