OVERVIEW

What is pneumothorax? Does it mean there is air in the chest cavity?

To be precise, it refers to the presence of gas in the pleural cavity. Pneumothorax occurs when gas enters the pleural cavity. The surface of the lungs is covered by a membrane called the visceral pleura, while the inner layer of the chest wall is lined with another membrane called the parietal pleura. The space between these two pleural layers is called the pleural cavity.

Normally, the pressure inside this sealed pleural cavity is lower than atmospheric pressure, which not only keeps the lungs expanded but also facilitates the return of venous blood and lymphatic fluid. When chest trauma affects the chest wall, lungs, or trachea, air enters the pleural cavity through the wound, leading to gas accumulation and impairing lung expansion.

What are the types of pneumothorax?

Based on the nature of the pleural rupture, pneumothorax is generally classified as closed, open, or tension (high-pressure). This classification is used to guide treatment decisions.

Additionally, there are classifications based on etiology, such as:

• Spontaneous pneumothorax: Occurs when lung or pleural diseases cause the rupture of the lung or visceral pleura, allowing gas from the lungs to enter the pleural cavity. This eliminates the original negative pressure in the pleural cavity, causing the lung to collapse due to its own elastic recoil.

• Traumatic pneumothorax: Occurs when the parietal pleura ruptures or is perforated, allowing external air to enter the pleural cavity through the chest wall. This is usually caused by trauma.

Spontaneous pneumothorax is further divided into secondary spontaneous pneumothorax and primary spontaneous pneumothorax. The former is often caused by lung diseases such as emphysema (ruptured bullae) or tuberculosis, while the latter has no obvious cause or trigger and may even show no abnormalities on X-ray. It is more common in young, tall, thin males who are otherwise healthy.

Which department should pneumothorax patients visit?

Respiratory medicine or cardiothoracic surgery.

SYMPTOMS

What are the common manifestations of pneumothorax?

The common manifestations are as follows:

• Chest pain: Most patients with pneumothorax experience varying degrees of chest pain, often caused by the stretching or tearing of pleural adhesions. The pain may occur suddenly, presenting as sharp or dull pain, and worsens with coughing or deep breathing. Elderly individuals, due to reduced sensitivity, may exhibit less noticeable chest pain compared to younger patients, potentially leading to delayed early diagnosis.

• Shortness of breath: This often occurs simultaneously with chest pain. In younger individuals, if lung compression is less than 30%, shortness of breath may not be obvious. However, elderly patients, who often have chronic lung diseases and poor lung function, may experience significant shortness of breath even with only 10% lung compression. In cases of tension pneumothorax, patients may exhibit progressive shortness of breath, even leading to shock or respiratory failure.

• Cough: Mostly a dry cough, triggered by pleural irritation. If infection is present, the cough may worsen, accompanied by purulent sputum.

CAUSES

How does closed pneumothorax occur?

Closed pneumothorax often occurs alongside rib fractures caused by trauma. Air enters the pleural cavity through lung lacerations or small chest wall wounds. If the chest wall wound closes quickly, the pleural cavity no longer communicates with the outside, and no additional air enters. In this case, the pressure in the pleural cavity remains lower than atmospheric pressure.

What commonly causes spontaneous pneumothorax?

The most common cause of spontaneous pneumothorax is the rupture of pulmonary bullae. Pulmonary bullae often develop due to conditions like emphysema, where increased residual air volume and pressure in the bronchioles and alveoli eventually lead to alveolar rupture, forming large air-filled sacs.

Who is more prone to pneumothorax?

Generally, the following groups are at higher risk:

• Tall, thin, healthy males: This body type is more susceptible to congenital elastic fiber dysplasia, leading to reduced alveolar wall elasticity. Overexpansion can form bullae, which may develop into pneumothorax under external factors.

• People with underlying lung diseases: Such as chronic bronchitis, emphysema, chronic tuberculosis, or bronchiolitis.

• Trauma patients: Including penetrating chest injuries (e.g., gunshot or stab wounds) and rib fractures.

• Special cases: Pregnancy-related pneumothorax, catamenial pneumothorax, neonatal pneumothorax, or patients on mechanical ventilation.

Which hospitalized patients may develop tension pneumothorax?

• Newborns: Most commonly seen in meconium aspiration syndrome, where meconium blocks airways, impairing ventilation and leading to bullae and pneumothorax. Newborns are usually monitored in intensive care, and prompt treatment typically ensures recovery.

• Patients with chronic lung diseases: For example, those with chronic fibrocavitary tuberculosis may experience bullae rupture due to severe coughing during hospitalization, leading to rapid breathing, dyspnea, cyanosis, and cold, clammy skin. Emergency interventions like closed thoracic drainage can quickly relieve symptoms, followed by treatment of the primary condition.

• Chest trauma patients: Some may not initially show pneumothorax symptoms but develop tension pneumothorax later due to severe coughing, turning minor lung injuries into open-valve wounds. This causes critical symptoms like dyspnea and cyanosis, requiring immediate medical attention.

• Mechanically ventilated patients: Mechanical ventilation, used for life support in respiratory failure, increases intrapulmonary pressure, raising the risk of bullae rupture and pneumothorax. Immediate thoracic drainage is needed. Once respiratory failure is resolved and ventilation is discontinued, pneumothorax usually heals well.

DIAGNOSIS

How is pneumothorax graded in terms of severity?

The severity of pneumothorax is classified based on the amount of air accumulated in the pleural cavity:

• Mild pneumothorax: Refers to lung collapse below 30%, with minimal impact on respiratory and circulatory functions, often presenting no obvious symptoms. The air may gradually absorb on its own, usually requiring no special treatment.

• Moderate pneumothorax: Refers to lung collapse between approximately 30% and 50%.

• Severe pneumothorax: Refers to lung collapse exceeding 50%, which can significantly impair lung ventilation and affect blood circulation.

In clinical practice, the volume of trapped air in pneumothorax is dynamic. Upon admission, patients typically undergo an estimation of the air volume. Regardless of the initial amount, active management is usually required to prevent worsening of the condition.

What tests are usually required for pneumothorax patients after hospitalization?

• Chest X-ray: The most basic and reliable method for diagnosing pneumothorax, showing the degree of lung collapse, pleural adhesions, mediastinal shift, pleural effusion, etc.

• Chest CT scan: More sensitive for detecting small amounts of air in the pleural cavity, especially useful for recurrent or chronic pneumothorax to identify underlying lesions.

• Arterial blood gas analysis: Essential in acute cases with cyanosis or hypoxemia to guide diagnosis and treatment.

• Preoperative routine tests: Required if surgical intervention is planned.

What is catamenial pneumothorax?

Catamenial pneumothorax is a special type of spontaneous pneumothorax triggered by menstruation in women. It recurs with the menstrual cycle, characterized by pneumothorax episodes typically occurring during menstruation rather than at its onset. The cause is often related to endometriosis.

TREATMENT

What are the treatment principles for pneumothorax patients?

The goal of pneumothorax treatment is to promote lung re-expansion, eliminate the cause, and reduce recurrence. Basic treatment measures include conservative therapy, air drainage, recurrence prevention, surgical intervention, and complication management.

When is conservative treatment chosen for pneumothorax?

Conservative treatment is suitable for mild primary or secondary pneumothorax. It includes bed rest, oxygen therapy, and symptom management such as pain relief, sedation, cough suppression, and laxatives to address triggers. Supportive care may be given to patients with poor physical condition or nutritional deficiencies.

Why does pneumothorax require active hospitalization?

Generally, if it is the first occurrence with minimal gas volume on chest X-ray and no symptoms like dyspnea or chest pain, hospitalization may not be necessary. However, recurrence often requires surgical intervention.

Intrapleural gas usually resolves spontaneously within two weeks. For large pneumothorax, pleural puncture or closed thoracic drainage is needed to remove gas and relieve lung and mediastinal compression, promoting early lung re-expansion. Antibiotics may be used to prevent infection.

Recurrent or life-threatening pneumothorax often requires surgery. Since patients cannot self-assess severity and close monitoring is necessary, hospitalization is crucial.

Why is active surgical treatment advocated for spontaneous pneumothorax?

Unlike traumatic pneumothorax, spontaneous pneumothorax often results from ruptured bullae. Conservative treatments, pleural puncture, or drainage only temporarily relieve symptoms without addressing the bullae, leading to high recurrence. Surgical removal of bullae and pleural abrasion to induce adhesions effectively prevents recurrence.

What is the common surgical procedure for spontaneous pneumothorax?

Video-assisted thoracoscopic surgery (VATS).

This minimally invasive approach is suitable for various thoracic conditions, offering advantages like smaller incisions, shorter duration, faster recovery, and reduced hospitalization. It is now the standard for spontaneous pneumothorax.

Though VATS is preferred, open thoracotomy remains necessary for severe pleural adhesions, diffuse bullae, or giant bullae. Despite larger trauma and slower recovery, it ensures low recurrence and definitive outcomes.

What complications may arise during pneumothorax treatment?

• Hemopneumothorax: Pneumothorax may rupture pleural vessels, causing blood accumulation. Bleeding usually stops after lung re-expansion. Persistent bleeding unresponsive to treatment warrants urgent thoracotomy.
• Pyopneumothorax: Common in secondary pneumothorax with infections like tuberculosis, Staphylococcus aureus, or anaerobes. Appropriate antibiotics are required.
• Subcutaneous emphysema: Gas may escape into subcutaneous tissues post-drainage, appearing as transparent bands on X-ray. It typically resolves as intrapleural gas is absorbed.

What anesthesia is typically used for pneumothorax surgery?

General anesthesia with double-lumen endotracheal intubation, standard for most thoracic surgeries.

How is pneumothorax surgery performed?

The procedure involves three steps:

• Repairing lung leaks or chest wall injuries;
• Treating lung lesions (e.g., resecting bullae);
• Inducing pleural adhesions to prevent recurrence.

A chest tube is placed post-surgery (one per side for bilateral cases), extending to the pleural apex.

Why is a chest tube placed after pneumothorax surgery?

To fully drain intrapleural gas, aid recovery, and monitor air leakage. It also helps assess residual gas and lung re-expansion via imaging.

When can the chest tube be removed post-surgery?

After confirming no air leakage and satisfactory lung expansion on X-ray.

Can patients move around with a chest tube before removal?

After ~12 hours of stable monitoring, patients are encouraged to walk and cough actively to promote lung expansion. The drainage bottle must remain below chest level.

Why is coughing encouraged after spontaneous pneumothorax surgery?

Since one lung is deflated during surgery, active coughing helps re-expand it, facilitating early tube removal and recovery.

Why does open pneumothorax require emergency treatment?

Caused by chest wall defects, it equalizes pleural pressure with the atmosphere, collapsing the lung and impairing respiration. Shifting mediastinal pressure during breathing disrupts cardiac and vascular function, causing severe hypoxia. Symptoms like dyspnea, cyanosis, or shock necessitate urgent intervention.

How is open pneumothorax managed in emergencies?

1. Pre-hospital: Seal the wound with a clean cloth and airtight covering (e.g., plastic bag), then transport immediately.

2. In-hospital: Cover with sterile Vaseline gauze and dressing, converting it to closed pneumothorax. Perform pleural decompression, oxygenate, and stabilize. Later, debride and suture the wound, followed by closed drainage.

Why is tension pneumothorax more urgent than open pneumothorax?

Caused by one-way valve injuries, it traps air in the pleural space, escalating pressure. This collapses the affected lung, shifts the mediastinum, compresses the healthy lung, and impairs cardiac function, rapidly leading to respiratory/circulatory failure. Symptoms include severe dyspnea, cyanosis, agitation, and shock.

How to identify and manage tension pneumothorax?

Pre-hospital: Look for chest fullness, subcutaneous emphysema, reduced respiratory movement, and dyspnea. Emergency treatment involves inserting a large needle or tube into the 2nd intercostal space (midclavicular line) to decompress.

In-hospital: Immediate chest tube drainage is done if confirmed by X-ray. Persistent symptoms may require surgery for adhesions, trapped lung, or tracheal injuries.

DIET & LIFESTYLE

What should pneumothorax patients pay attention to in daily life?

• Patients should avoid strenuous exercise for six months after surgery, such as long-distance running or climbing stairs;

• During recovery, slow-paced walking is allowed under a doctor's advice.

• Avoid air travel if possible, as high-altitude pressure may cause secondary tearing of newly healed wounds.

• Heavy physical labor or high-intensity work should be minimized to prevent recurrence.

What should pneumothorax patients pay attention to in their diet?

The general principle is to maintain a diverse and scientific diet to meet nutritional needs and promote recovery;

• Vegetables, fruits, meat, eggs, and dairy products can all be consumed, but avoid foods or cooking methods that are usually irritating;

• Increase intake of fiber-rich foods moderately and reduce hard-to-digest foods.

PREVENTION

How to Prevent Pneumothorax?

Patients with pneumothorax who have not undergone surgery to address the underlying cause may experience recurrence. They should avoid strenuous physical activities such as weightlifting, diving, or lifting heavy objects, as sudden exertion can trigger pneumothorax. In daily life, seek medical attention promptly if symptoms like chest tightness, shortness of breath, or difficulty breathing occur.

After surgical discharge, rest for 2-4 weeks and avoid vigorous or excessive activities—such as upper limb pulling movements or chest expansion exercises—for at least 3 months (3–6 months). Avoid sudden exertion and breath-holding; maintain regular bowel movements.

Prevent upper respiratory infections and avoid severe coughing. If primary conditions like pulmonary bullae or tuberculous cavities exist, address them promptly to prevent pneumothorax complications or recurrence.