Pathology of pneumothorax

2021-01-28 12:00 AM

Normally, the air enters the pleura when exhaled and exits when exhaling, if exhaled but the air cannot escape, the valve is overflow, thus causing increasing difficulty in breathing


Pneumothorax was described by Laennec from 1819 and by 1888 Galliard more clearly described. 1937 Sattler scans the thoracic path of the ruptured bronchial bladder causing pneumothorax and then the pneumothorax and pneumothorax burst into the pleura.

Pleural pneumothorax is a condition in which air enters between the two pleural leaves, deflating the lungs, with complete and incomplete pneumothorax.


Primary pneumothorax

Secondary pneumothorax


Spontaneous pneumothorax is common in young people aged 20-30 years, the rate of men 4/1 compared to women. According to Salmeron. (1995), the annual rate of pneumothorax is 9 / 100,000 population, recurrence> 28%.

About 20% of pneumothorax is a complication of lung infections.

About 40% of pneumothorax is due to tuberculosis and (40% of unknown cause.

25% of pneumothorax recurred after 2 years, 50% recurred after 6 years.

Usually, pneumothorax occurs in severe asthma attacks.


There are many causes of primary or secondary pneumothorax.

Primary pneumothorax

Common in young people and men> women = 4 times usually due to:

Broken air balloon waste.

Viral alveoli.

The reason is unknown.

Usually occurs in people with a history of smoking, exertion, coughing, stress ...

Secondary pneumothorax

Pulmonary tuberculosis.

Bronchitis - lung infection (20%) 

The most chronic obstructive pulmonary disease is emphysema.

During an asthma attack.

Bronchial infiltration or pleural metastasis.

Pulmonary disease, pulmonary fibrosis, silica dust, Sarcoidosis 

Other lung diseases 

Pneumothorax due to trauma, exploration procedure

Injury punctured chest, rib fracture punctured the lungs 

Procedures of pleural puncture, pleural biopsy, endotracheal intubation, rescue.

Poke the pulse under the blow 

Drainage of the pleura 



Mechanism of pathogenesis

Normally, the pressure in the pleural space is negative (-3 to - 5 cm H20), when the air enters the pleura, the lung parenchyma shrinks, the thoracic dilate, resulting in vital capacity, total capacity and capacity. reduced sediment accumulation.

The degree of respiratory dysfunction due to pneumothorax depends on the degree of airflow (atelectasis) and lung function prior to the pneumothorax - Pneumothorax may be present after pneumothorax due to ligament damage between 2 pleurae.

Normally, the air enters the pleura when inhaled in and out when exhaled. If exhaled but the air cannot escape, it is a valvular overflow, thus causing increasing difficulty in breathing and leading to severe respiratory failure. mediastinal deflection.

Pneumothorax can be caused by a piercing wound through the chest wall or through the viscera due to perforation, rupture of the alveoli, rupture of a balloon, or rupture of a lung abscess.

If the pleural fistula is blocked, the overflow will fade.

If a pneumothorax occurs over 1 pleural thickening, it will cause incomplete pneumothorax.


Full spontaneous pneumothorax

Common in young people (20-30 years old) with the first symptom of sudden severe chest pain like a knife, makes the patient dare not breathe deeply, coughs violently and cough increases pain. There may be dizziness if the pneumothorax is rapid and large, rapid pulse, mild, low blood pressure, cold hands and feet, sweating, rapid shallow breathing, panic anxiety ... then symptoms subside. after a few hours, a few days.

Examination of the lung reveals enlarged side chest, wide intercostal spaces, drum-like echoes, reduced sound vibrations, and total lung sounds are heard, or echoes can be heard. Knocking out, vibrating sound reduced, and bronchial tone loss is called the Galliard trilogy. In the later stages, there may be a cloudy knuckle in the bottom of the lung due to blood or post-effusion.

If the pneumothorax is mild, the symptom of mechanical function is not clear, pulmonary resonance and manifestations of respiratory failure are not apparent.

Laboratory testing

Standard chest radiograph straight, inclined:

Shows that the side of thoracic pneumothorax is enlarged, seen brighter than normal, the entire lung parenchyma is pushed towards the hilum to form a muzzle, the mediastinum is pushed to the opposite side, the diaphragm is pushed down.  Can see the diaphragmatic angle due to haemorrhage or combined effusion or horizontal (multiple) fluid level, sometimes seen the damage of the master lung tissue suggest the cause of pneumothorax.

If the pneumothorax is incomplete, only a focal bright area is a visible and visceral leaf is thick and sticky.

Computerized tomography:

Can help identify lung damage below the spillway and help determine the cause of the spill, but not always.

Other exploration:

By pressure gauge: Helps determine the pressure in the pleura to assess whether the pneumothorax has a valve or not, has plugged the opening again.

Thoracoscopy: This procedure helps to evaluate quite well the damage to the master lung tissue causing pneumothorax, especially when it is necessary to drain the pleura and helps to prevent recurrent pneumothorax or detect other air bubbles. and klebs

Clinical forms

Complete (complete) pneumothorax.

Local (incomplete) pneumothorax: due to old pleural thickening.

Valvular pneumothorax: Air enters the pleura but cannot escape, this is a severe form that can lead to death without timely intervention.

Both sides pneumothorax: Rare, often fast death.

Pneumothorax in patients with chronic respiratory failure (COPD, tuberculosis ...) causes acute respiratory failure / chronic respiratory failure leading to decompensated respiratory failure.

Silent pneumothorax: usually localized pneumothorax, mild, accompanied by bronchial asthma, emphysema ... should only be detected when taking a chest film.


Implementing the quadrants

It is usually not difficult in the case of complete pneumothorax with strong muscle symptoms such as sudden pain in the chest like a knife, accompanied by acute respiratory failure (shortness of breath, shallow, purple, sweating.,.) or accompanied by shock (small tachycardia, blood pressure drops, manifestations of acute heart failure, cold limbs ...) and Galliard triangle. The main diagnosis is X-rays. For localized, silent forms, it must be associated with the history, respiratory disease, ease and important factor is radiograph.

Diagnose the cause

Usually, it is difficult because about 50% of pneumothorax cases are of unknown cause. Must rely on history, medical history and clinical symptoms along with other tests to identify the main disease-causing pneumothorax.

Most pneumothorax is spontaneous and has easy factors such as exertion, strong cough, severe bronchial asthma attacks, tress ...

Must pay attention to the chest exploration procedures such as endotracheal intubation, bronchoscopy, subclavius measurement, lung biopsy, trans-parietal pleura, pleural effusion, pleural drainage ... some schools with the probe, liver biopsy, acupuncture and some other procedures.

Chest injury: Common is a broken rib.

Distinguished guess

When pneumothorax: In both lungs, there is no acute functional muscle symptom, total bilateral reduction in the bronchial tone, possibly chronic respiratory failure, is confirmed by radiological diagnosis.

Lung cocoon: X-ray image and necessary computerized tomography.

Lung cavity: Based on history, medical history and X-ray images.


Bleeding, pleural fluid after the gas spill.

Pleural infection through the air into the pleura.

Acute heart failure, acute respiratory failure.

Valvular pneumothorax.

Thickening of the pleura.

Chronic pneumothorax (irreversible).

Pneumothorax recurred after many years.


Supportive treatment

Bed rest during the acute phase, fowler lying down if the acute respiratory failure is present.

Avoid anxiety, emotions: Must be quiet, can add sedatives such as Valium or Diaz├ępam, valium 5 mg x 1-2 tablets/day, but pay attention to patients with chronic respiratory failure.

Do not work hard after an attack.

Eat easily digestible snacks, stop smoking.

General treatment

Pain relief: Paracetamol or Acetaminophen 500 mg x 3-4 tablets/day can be used if the pain is severe.

Cough relief: Because cough can increase chest pain or make it difficult to breathe: use a cough suppressant such as Paxeladin 3 v / day (no respiratory centre depression).

Oxygen through the nose with an average dose of 2-3 l / 1 'if there is a respiratory failure but must pay attention to the type of gas spill with valves or without valves.

Antibiotics: Often pneumothorax will be infected by bacteria from the air or from the bronchus into the pleura. Systemic antibiotics and types with a broad spectrum of bacteria such as Cephalosporin III: 3 - 4g / 24 TB or TM should be used.

Treatment of air spills

The aim is to lead the lung tissue to lead to avoid acute respiratory failure due to atelectasis. The main method is to suck pleural air with a syringe, the position usually chosen is the II ribs on the mid-attack line.

Depending on the type of air spill that has different indications.

Closing pleural pneumothorax: Normally, the gas absorbs itself again after a while, if the amount is not reduced in 3-4 days, you can use a large syringe and needle to suck, should not suck early, and only Suction slowly, a small amount to avoid shock due to organ position change or sudden pressure drop.

Open pleural pneumothorax: Catheter must drain the pleura with negative pressure, insert into the medial or intercostal II intercostal 4-5 in the anterior axillary line, put the catheter in the direction of the lung, or use a vacuum (- 20 to 40 cm H20). After 3-5 days, clamp the catheter again: 24 - 48 hours to see if the gas spill returns or not, monitor pulse, temperature, blood pressure and check by X-ray to evaluate.

Valvular pneumothorax: This is a medical emergency and should be done quickly.

If the conditions are not available, use a large needle to poke the pleura in the stated position and connect with the Serum chain into a shape containing 9 Nacl, but draw the chain down to 10 -15 cm.

If using metal 14 - 16 hours to poke through the machine continuously, suction pressure - 15 cmH2O.

Treatment to prevent recurrent air spills

It is possible to find the lesions causing TKMP by endoscopic methods to determine such as ambering surgery, sealing the hole of the visceral leaf.

Thickening the pleura with bio-glue.

Treat the cause of pneumothorax

In Vietnam, the most common cause is tuberculosis, in addition to infections, viruses and some other factors, so to determine the cause for treatment to avoid recurrence or worsening of TKMP.

Take care to avoid easy factors such as exertion, stress, coughing a pulse, and smoking.

 Surgical treatment

Indicates surgical treatment in the following cases.

Pneumothorax - pleural bleeding due to trauma.

Emphysema - hat collapse lung abscess or TB 

Pneumothorax due to chest injury. (open injury, broken ribs, foreign bodies ...).