What Are the Different Causes of Pneumothorax?

Pneumothorax (pneumothorax) refers to gas entering the pleural cavity, causing a state of accumulation of gas, called pneumothorax. The lung tissue and visceral pleura are often ruptured due to lung disease or external force, or the fine emphysema bubbles near the surface of the lung are ruptured. Traumatic pneumothorax is caused by trauma to the chest wall or lungs; spontaneous rupture of lung tissue due to disease is called "spontaneous pneumothorax", and artificially injecting air into the pleural cavity for treatment or diagnosis is called "artificial pneumothorax". Pneumothorax can be divided into closed pneumothorax, open pneumothorax and tension pneumothorax. Spontaneous pneumothorax is more common in young men or men with chronic branches, emphysema, and tuberculosis. This disease is one of the pulmonary emergency cases, severe cases can be life threatening, timely treatment can be cured.

Basic Information

English name: pneumothorax
Visiting department: Respiratory
Multiple groups: Young adult men with chronic branch, emphysema, and tuberculosis

Common causes: Strenuous exercise, cough, heavy lifting or upper arm lift, blunt injury, tuberculosis, etc.
Common symptoms: Chest tightness, shortness of breath, cyanosis, cough, etc.

Causes of pneumothorax

The factors that induce pneumothorax are strenuous exercise, coughing, heavy lifting or upper arm lift, weight lifting exercise, hard solution of stool and blunt injuries. When a severe cough or strong bowel movements occur, the pressure in the alveoli rises, leading to rupture of the original damaged or defective lung tissue and pneumothorax. With an artificial respirator, pneumothorax may occur if the aspiration pressure is too high.

Primary pneumothorax

Also called idiopathic pneumothorax. It refers to pneumothorax that occurs in healthy people whose routine X-ray examination of the lungs fails to detect obvious lesions. It occurs in young people, especially men who are lean and elderly. Smoking is the main cause of primary pneumothorax, and the incidence of pneumothorax has a significant dose-response relationship with the amount of smoking.

2. Secondary pneumothorax

Its mechanism is caused by the formation of bullae or direct damage to the pleura on the basis of other lung diseases. Often based on chronic obstructive emphysema or fibrous lesions after inflammation (such as silicosis, chronic tuberculosis, diffuse pulmonary interstitial fibrosis, cystic pulmonary fibrosis, etc.), bronchiolitis is narrow and distorted, producing a valve mechanism The formation of bullae. Swelling emphysema is degenerative due to nutritional and circulatory disorders. Chronic obstructive pulmonary disease (COPD) is the most common cause of secondary pneumothorax. About 57% of secondary pneumothorax is caused by COPD. With the worsening of COPD, the risk of pneumothorax also increases.

3. Special type of pneumothorax

(1 ) Menstrual pneumothorax is a pneumothorax with recurrent episodes related to the menstrual cycle.

(2 ) Pregnancy with pneumothorax Most young women in childbearing period. Patients with this disease develop pneumothorax with each pregnancy. According to the time when pneumothorax appears, it can be divided into early (3 to 5 months of pregnancy) and late (more than 8 months of pregnancy).

(3 ) Spontaneous pneumothorax in the elderly over 60 years old is called spontaneous pneumothorax in the elderly. In recent years, the incidence of this disease has increased. More men than women. Most of them are secondary to chronic lung diseases (about 90%), with chronic obstructive pulmonary diseases being the first.

(4 ) Traumatic pneumothorax is mostly caused by the lung being punctured by a fractured rib, and it can also be caused by violent bronchial or lung tissue contusion or laceration, or bronchial or lung rupture caused by a sharp rise in airway pressure. Sharp wounds or firearm injuries penetrate the chest wall and hurt the lungs, bronchial tubes, and trachea or esophagus. They can also cause pneumothorax, and most of them are pneumothorax or pneumothorax. Occasionally, a closed or penetrating diaphragm rupture is accompanied by a gastric rupture and pneumothorax.

Clinical manifestations of pneumothorax

Pneumothorax

The severity of the symptoms depends on how quickly the disease starts, the degree of lung compression, and the condition of the primary lung disease. Typical symptoms are sudden chest pain, followed by chest tightness and dyspnea, and irritating cough. This type of chest pain is usually acupuncture or knife-cut and lasts for a short time. Irritant dry cough is caused by gas irritating the pleura. Most of the patients with rapid onset, large pneumothorax, or with lung lesions, have shortness of breath. Some patients have incentives to have a cough, hold their stools or lift heavy objects before pneumothorax occurs, but many patients develop disease during normal activities or quiet rest. Moderate pneumothorax in young healthy people is rarely uncomfortable, and sometimes patients are only found during physical examination or routine chest radiography; in elderly with emphysema, even if the lungs are compressed less than 10%, they can produce significant breathing difficult.

2.Tensile pneumothorax

Patients often show high nervousness, fear, irritability, shortness of breath, suffocation, cyanosis, sweating, weak and fast pulses, decreased blood pressure, cold and cold skin, and even unconsciousness and coma, if not timely Rescue often causes death. Pneumothorax patients generally have no fever, increased white blood cell counts, or increased erythrocyte sedimentation. If these symptoms are present, they usually indicate an original pulmonary infection, such as tuberculous or purulent inflammation, or complications such as exudative pleurisy or empyema. .

3. Bilateral pneumothorax

Bilateral pneumothorax can occur in a small number of patients, with dyspnea being the most prominent manifestation, followed by chest pain and cough. At the same time, it was found that bilateral heterogeneous spontaneous pneumothorax, that is, one side occurred first and then became bilateral pneumothorax, which was relatively higher than the bilateral spontaneous pneumothorax, reaching 83.9%.

4. Partial pneumothorax

Patients with mediastinal emphysema have more severe dyspnea and often have obvious cyanosis. Rarely, when pneumothorax occurs, pleural adhesions or pleural blood vessels tear to produce blood pneumothorax. If the amount of bleeding is large, it can be manifested as pale signs, cold sweat, weak pulse, and decreased blood pressure. But most patients have only a small amount of bleeding.

5. Asthma complicated by pneumothorax

When the patient is in a persistent state of asthma, if the condition continues to worsen through active treatment, it should be considered whether pneumothorax is complicated; on the contrary, pneumothorax patients sometimes show asthma-like symptoms, shortness of breath, and even both lungs filled with wheezing. Cavity pumping decompression, shortness of breath and wheezing disappeared.

Secondary pneumothorax is associated with underlying lung disease, with more severe symptoms and more complications, and is prone to cause tension pneumothorax.

Pneumothorax

Imaging examination

X-ray examination is an important method for diagnosing pneumothorax. Chest radiography is the conventional method for the diagnosis of pneumothorax. If clinically suspected pneumothorax and the anterior chest radiograph are normal, a chest chest radiograph or a lateral chest radiograph should be performed. Most of the pneumothorax films have a clear pneumothorax line, that is, the boundary line between the atrophic lung tissue and the gas in the pleural cavity, showing a convex line shadow. The outside of the pneumothorax line is a light-transmitting area without lung texture, and the line is compressed lung tissue. A large number of pneumothorax can be seen mediastinum, the heart shifted to the healthy side. Gas-liquid surface is visible when pleural effusion is combined. Local pneumothorax is easily missed during posterior anterior X-ray examination. Lateral chest radiographs can assist diagnosis. Rotating position under X-ray perspective can also be found. Mediastinal emphysema should be considered if there is a light-transmitting band around the edge of the heart. Chest radiography is the most commonly used diagnostic method for the diagnosis of pneumothorax. CT is more sensitive and accurate than X-ray chest radiography for the identification of small amounts of pneumothorax, localized pneumothorax, and bullae and pneumothorax. The basic CT of pneumothorax is a very low density gas shadow in the pleural cavity, accompanied by changes in the compression and collapse of the lung tissue.

2. Capacity of pneumothorax

In terms of volume, it is difficult to estimate accurately from a chest radiograph. If an accurate estimate of pneumothorax volume is needed, a CT scan is the best method. In addition, CT scan is the only effective method to distinguish pneumothorax from some difficult cases (such as surgical emphysema with apnea due to inconspicuous pulmonary compression, suspicious bullae with complex cystic lung disease, etc.).

3. Measurement of intrathoracic pressure

Helps in the typing and treatment of pneumothorax. The diagnosis of pneumothorax type (closed, open, and tonic) can be determined by measuring intrathoracic pressure.

4. Blood gas analysis and pulmonary function tests

Arterial blood gas analysis is abnormal in most patients with pneumothorax, with PaO ₂ below 80 mmHg in more than 75% of patients. 16% of patients with secondary pneumothorax had PaO ₂ <55mmHg and PaCO ₂ > 50mmHg. Pulmonary function tests are not helpful in detecting the occurrence or volume of pneumothorax, so they are not recommended.

5. thoracoscopy

The location of the pleural rupture and the underlying lesions can be identified, and treatment can be performed at the same time.

Pneumothorax diagnosis

It is not difficult to diagnose the disease based on clinical symptoms, signs, and X-ray findings. When obstructive emphysema is complicated by spontaneous pneumothorax, it is often confused with its original symptoms and signs. X-ray examination is needed for diagnosis.

Differential diagnosis of pneumothorax

Bullae

Onset is slow and the course is long; pneumothorax is often acute and has a short history. X-ray examination of pulmonary bullae is a circular or oval light-transmitting area, located in the lung field, and there are still small strip-like textures; while pneumothorax is a strip-shaped shadow, located in the chest cavity outside the lung field. Pulmonary bullae around the lungs are easily misdiagnosed as pneumothorax. The line of bullae on the chest radiograph is concave facing the lateral chest wall; the convex side of the pneumothorax often faces the lateral chest wall. Chest CT is helpful for differential diagnosis. Over a longer period of time, the size of the bullae rarely changed, while the pneumothorax morphology gradually changed and eventually disappeared.

2. Acute myocardial infarction

Pneumothorax-like clinical manifestations, such as acute chest pain, chest tightness, dyspnea, and shock, but patients often have a history of coronary heart disease, hypertension, changes in heart sound properties and rhythm, no pneumothorax signs, electrocardiogram or chest X-ray examination. Helps identify.

3. Pulmonary embolism

There are underlying diseases of embolic origin, no signs of pneumothorax, and chest X-ray examination can help identify.

4. Chronic obstructive pulmonary disease and bronchial asthma

Chronic obstructive pulmonary disease, dyspnea, is slowly exacerbated for a long time, and bronchial asthma has a history of recurrent asthma for many years. When patients with chronic obstructive pulmonary disease and bronchial asthma have a sudden increase in dyspnea and chest pain, the possibility of concurrent pneumothorax should be considered. Chest X-ray examination can help identify.

Pneumothorax treatment

Spontaneous pneumothorax is one of the emergency department of respiratory medicine. If it is not handled in time, it often affects work and daily life, especially the diagnosis and treatment of patients with persistent or recurrent pneumothorax are not timely or appropriate, often damaging lung function and even threatening life. Therefore, it is very important to actively treat and prevent recurrence. In determining the treatment plan, the symptoms, physical signs, X-ray changes (degree of lung compression, presence or absence of mediastinal displacement), pleural pressure, pleural effusion, pneumothorax occurrence rate, and original lung function status should be considered. Choose the appropriate method for the first onset or recurrence, whether the hemodynamics is stable, the size of pneumothorax, the cause of pneumothorax, the onset or recurrence, and the initial treatment effect. Basic treatment principles include general treatment of bed rest, conservative observation treatment, exhaust therapy, pleural cavity aspiration, closed chest drainage, preventive measures for recurrence, surgical treatment, and prevention of primary disease and complications. The goal of early treatment of pneumothorax is to eliminate tension pneumothorax and relieve dyspnea. Choose a reasonable treatment method based on whether the patient is primary or secondary.

General treatment

Patients with pneumothorax should be absolutely bed rested, fully inhale oxygen, and speak as little as possible to reduce lung activity, which is conducive to gas absorption and lung expansion. It is suitable for the first episode, the lung collapse is below 20%, and there is no dyspnea.

Exhaust therapy

It is suitable for patients with obvious dyspnea and severe lung compression, especially those who need emergency venting for tension pneumothorax. Hemodynamic instability suggests that tension pneumothorax may be needed, and immediate decompression of the second intercostal puncture in the midline of the clavicle is required.

(1) Pleural cavity aspiration method.

(2) Closed chest drainage.

3. Pleural adhesions

Due to the high rate of spontaneous pneumothorax recurrence, in order to prevent recurrence, simple physical and chemical agents, immune activators, fibrin supplements, medical adhesives, and biostimulants are introduced into the pleural cavity, and the pleura and parietal pleura are adhered, thereby Eliminate the pleural space, so that no air accumulates, which is called "pleural fixation." The British Thoracic Society (BTS) guidelines consider that chemical pleural fixation is only suitable for patients with persistent air leaks that are not suitable for surgical treatment and is not recommended as the preferred treatment.

4. Lung or bulla rupture closure method

In the diagnosis of emphysema and bullae rupture without other substantial lung lesions, endoscopic use of laser or adhesive can be used to close the cleft without opening the chest.

5. Surgical treatment

Both the American College of Chest Physicians (ACCP) and BTS guidelines recommend that drainage is considered unsuccessful or that drainage is considered more than 4 days before surgery is considered. The first purpose of the operation is to control air leaks, the second is to treat lung lesions, and the third is to prevent the recurrence of pneumothorax by adhering the visceral and parietal pleura. In recent years, due to the development of thoracic surgery, mainly the improvement of surgical methods and the improvement of surgical instruments, especially the advancement of television thoracoscopic instruments and technology, surgical treatment of spontaneous pneumothorax has become a safe and reliable method. Surgery can eliminate the breach of the lungs, and can fundamentally treat the primary lesions, such as bullae, bronchopleural fistula, perforation of tuberculosis, etc., or ensure pleural fixation through surgery. Therefore, it is an effective method for treating refractory pneumothorax and the most effective measure for preventing recurrence. Studies have shown that patients with spontaneous pneumothorax leak for more than 4 days or undergoing re-thoracic drainage underwent video assisted thoracoscopic surgery (VATS) for bullous bullectomy and pinning combined with mechanical or chemical pleural fixation.

6. Bronchoscopic occlusion treatment

On the basis of conventional closed chest drainage, bronchoscopic balloon exploration and selective bronchial occlusion are used to block the bronchi leading to the broken lung for therapeutic purposes.

Pneumothorax prevention

1. Pneumothorax has a high recurrence rate. Patients need to be informed of the symptoms that suggest a recurrence of pneumothorax. Pneumothorax often manifests as sudden chest pain and dyspnea, but there are also a small number of patients without obvious symptoms.

2. The BTS guidelines recommend that all patients need to see a pneumothorax 2 to 4 weeks after the initial onset of pneumothorax, review pneumothorax absorption, check for underlying lung disease, and whether further treatment is needed.

3. Patients may consider participating in normal work and activities after the symptoms disappear. However, strenuous exercise and physical collision exercise can only be performed after imaging shows that the pneumothorax has completely disappeared.

4. Quitting smoking can significantly reduce the recurrence of primary pneumothorax, and the relative risk is reduced by about 40% to help them successfully quit smoking.

5. Because underwater activities such as diving can increase the recurrence rate of pneumothorax, and the amount of pneumothorax will increase during the ascent of the dive, increasing the risk of tension pneumothorax, the BTS guidelines recommend that treatment is not performed accurately (such as partial pleural resection) Patients should avoid diving for life. For professional divers, after the onset of pneumothorax, a partial pleural resection is required before resuming diving.

6. Although taking a plane does not increase the risk of pneumothorax, it can aggravate pneumothorax at high altitudes, with serious consequences. Therefore, patients with pneumothorax who have not undergone closed chest drainage should avoid flying, and need treatment or imaging data to indicate pneumothorax You can take the plane after absorption.