The pleural cavity consists of the pleural wall layer and the dirty layer, which are airtight potential cavities that do not contain air. When the pleura is broken for any reason and air enters the pleural cavity, it is called pneumothorax. At this time, the pressure in the pleural cavity rises, and even the negative pressure becomes positive pressure, which compresses the lungs and obstructs the venous blood flow back to the heart, producing different degrees of lung and heart dysfunction. The pneumothorax caused by thoracic trauma, needle treatment, etc. is called traumatic pneumothorax. The most common pneumothorax is caused by lung diseases that rupture the lung tissue and dirty layer pleura, or the pulmonary blisters and tiny emphysematous vesicles near the lung surface rupture on their own, and the air in the lung and bronchus escapes into the pleural cavity, which is called spontaneous pneumothorax.
Traumatic pneumothorax, in penetrating injuries, accounts for about 30% to 87.6%. The air in the pneumothorax in the majority of cases originates from the lung being punctured by the broken end of the rib fracture (superficially called pulmonary rupture, deep into the fine bronchi called pulmonary laceration), or due to the contusion of bronchi or lung tissue caused by the action of violence, or due to the rupture of bronchi or lung caused by the rapid increase in pressure in the airway. Pneumothorax can also be caused by sharp or firearm injuries that penetrate the chest wall and injure the lungs, bronchi and trachea or esophagus, and is mostly hemopneumothorax or pneumothorax. Occasionally, closed or penetrating diaphragmatic rupture is accompanied by gastric rupture and results in pneumothorax.
Clinical types
According to the rupture of the dirty pleura and its effect on the intrathoracic pressure after its occurrence, spontaneous pneumothorax is divided into the following three types.
1.Closed pneumothorax (simple)
2.Open pneumothorax
3.Tension pneumothorax
Due to the adhesion and pulling between the two layers of pleura, the rupture is continuously opened and the air moves freely in and out of the pleural cavity during inspiration and expiration. The pressure in the pleural cavity on the affected side is 0 up and down, and the pressure does not decrease after several minutes of observation after pumping.
According to the pathogenesis pneumothorax can be divided into the following types.
1, post-traumatic pneumothorax: caused by a sharp object stabbing the chest.
2, primary pneumothorax: pneumothorax occurring in healthy people without obvious lung lesions, mostly seen in young adults aged 20-40 years old, and more common in men.
3, secondary pneumothorax: pneumothorax occurring secondary to various diseases of the lung, such as chronic bronchitis, emphysema, tuberculosis, lung cancer, etc.
Primary pneumothorax is usually caused by congenital lung tissue hypoplasia, the presence of small pulmonary blisters or pulmonary blisters under the pleura after breaking the wall, the lesion is often located in the apical part of the lung; secondary pneumothorax is due to the original lung lesion, the formation of subpleural pulmonary blisters rupture or due to the lesion itself directly damage the pleura.
Spontaneous pneumothorax is mostly unilateral, and only about 10% of the patients have bilateral pneumothorax at the same time, while secondary pneumothorax has a great chance of being bilateral at the same time, and patients often have sudden chest pain after pneumothorax, which is sharp and persistent stabbing pain or cutting pain. The severity is closely related to the speed and type of pneumothorax, the degree of lung atrophy and the basic lung function. Unilateral closed pneumothorax, especially in young people with normal lung function, can have no obvious dyspnea, or even 80-90% lung compression or only feel slightly short of breath when moving or going upstairs, while tension pneumothorax or original The elderly with tension pneumothorax or pre-existing obstructive emphysema can have obvious dyspnea, and even when the lung compression is only 20-30%, they have shortness of breath. Irritant dry cough is produced by gas irritation of the pleura, mostly not serious, without sputum or occasionally a small amount of blood sputum, which may come from the site of lung rupture.
Clinical manifestations
Patients often have triggering factors such as holding heavy objects, breath-holding, and strenuous exercise, but there are also cases of pneumothorax occurring during sleep, in which the patient suddenly feels chest pain, shortness of breath, and breath-holding on one side, and may have coughing but little sputum. If the air accumulation is large or if there is an existing extensive lung disease, the patient often cannot lie down. If the patient lies on his or her side, he or she is forced to put the affected side of the pneumothorax on top to reduce shortness of breath. The degree of dyspnea is related to the amount of pneumoperitoneum and the extent of the original intrapulmonary lesion. When there are pleural adhesions and reduced lung function, even a small amount of limited pneumothorax may result in significant chest pain and shortness of breath.
Tension pneumothorax, due to the sudden elevation of the chest cavity, the lung is compressed, the mediastinum is displaced, there is a serious respiratory and circulatory disorder, the patient has a tense expression, chest tightness, and even arrhythmia, often struggling to sit up, irritable, with cyanosis, cold sweat, rapid pulse, deficiency, and even respiratory failure and unconsciousness.
When pneumothorax is complicated by severe asthma or emphysema, symptoms such as shortness of breath and chest tightness are sometimes not easily detected, so it is necessary to compare carefully with the original symptoms and perform chest X-ray. Physical examination shows that the trachea is mostly shifted to the healthy side and there are signs of pneumothorax in the chest.
Signs: If a small amount of air accumulates in the chest, there are often no obvious signs. When there is a large amount of pneumonia, the patient’s chest is full, the rib space widens, and the respiratory degree is weakened; voice tremor and voice resonance are weakened or disappeared. The trachea and heart are shifted to the healthy side. Percussion on the affected side shows a drum sound. In the case of right-sided pneumothorax, the hepatic turbid boundary may be shifted downward. On auscultation, the breath sounds on the affected side are diminished or absent. If there is liquid pneumothorax, the sound of water vibrating in the chest can be heard. In case of hemopneumothorax, blood pressure may drop and even hemorrhagic shock may occur.
Imaging examination
X-ray chest examination is an important method to diagnose pneumothorax, which can show the degree of lung compression, intrapulmonary lesions and the presence of pleural adhesions, pleural effusion and mediastinal displacement. The typical X-ray of pneumothorax is a thin line of convex arc-shaped shadow, called pneumothorax line, with increased translucency outside the line, no lung texture, and compressed lung tissue inside the line. In massive pneumothorax, the lung retracts toward the lung door and appears as a round spherical shadow. A large number of pneumothorax or tension pneumothorax often shows a shift of the mediastinum and heart to the healthy side. In combination with mediastinal emphysema, transilluminated bands are seen next to the mediastinum and next to the cardiac border.
Tuberculosis or chronic inflammation of the lung causes multiple adhesions of the pleura, and when pneumothorax occurs, it is mostly confined and sometimes the pneumothorax is interconnected. If the pneumothorax extends to the lower thoracic cavity, the angle of the rib diaphragm becomes sharper. When combined with pleural effusion, the pneumo-liquid plane is shown, and the fluid surface can be seen to move under fluoroscopic change of body position. The pneumothorax can be easily missed in the posterior-anterior chest radiograph, and the lateral chest radiograph can assist in the diagnosis, or the pneumothorax can be found by turning the body position under x-ray fluoroscopy.
CT is more sensitive and accurate than X-ray chest radiograph in differentiating small volume pneumothorax, limited pneumothorax and pneumomediastinum from pneumothorax.
The size of pneumothorax volume can be judged based on X-ray chest radiographs. Since the pneumothorax volume approximates the ratio of the cubic lung diameter to the cubic unilateral chest diameter [(unilateral chest diameter. a lung diameter.) /unilateral thoracic cavity diameter.)] The distance from the lateral chest wall to the edge of the lung is about 25% of the unilateral thoracic volume at 1cm and about 50% at 2cm. Therefore, the distance from the lateral chest wall to the edge of the lung ≥ 2 cm is a large amount of pneumothorax, and < 2 cm is a small amount of pneumothorax. If the size of the pneumothorax is estimated from the apical pneumothorax line to the top of the chest cavity, the distance ≥3cm is a large amount of pneumothorax, and <3cm is a small amount of pneumothorax.
Spontaneous pneumothorax sometimes resembles other heart and lung diseases and should be differentiated.
I. Bronchial asthma and obstructive pulmonary emphysema
There is shortness of breath and dyspnea, and the signs are similar to spontaneous pneumothorax, but the dyspnea in emphysema is slowly aggravated for a long time, and bronchial asthma patients have a history of recurrent asthma attacks for many years. When asthma and emphysema patients have sudden worsening of dyspnea and chest pain, the possibility of complicated pneumothorax should be considered, and X-ray examination can make the distinction.
Second, acute myocardial infarction
Pulmonary maculopathy
It can also form tension cavity or giant cavity due to obstruction of bronchial valve, with slow onset and non-severe shortness of breath, and when the chest fluoroscopy is done from different angles, the pulmonary blister or bronchogenic cyst can be seen as round or oval translucent area, and no hairline pneumothorax line can be seen at the edge of the blister, and there are tiny bar texture inside the blister, which is the remnant of lung lobules or blood vessels. The pulmonary blister expands peripherally, pressing the lung toward the apical region of the lung, the angle of the rib diaphragm, and the angle of the heart diaphragm, while the pneumothorax presents as a translucent band on the outside of the chest, in which no lung lines are visible. The pressure within the pulmonary blister is similar to atmospheric pressure and there is no significant change in the volume of the blister after aspiration.
Others, such as peptic ulcer perforation, diaphragmatic hernia, pleurisy and lung cancer, sometimes due to acute chest pain, epigastric pain and shortness of breath, should also be distinguished from spontaneous pneumothorax.
1, pleural cavity consists of pleural wall layer and dirty layer, which is a closed potential cavity without air, any reason to break the pleura, air into the pleural cavity, called pneumothorax. The most common pneumothorax is caused by lung diseases that rupture the lung tissue and the dirty layer of pleura, or the pulmonary blister near the surface of the lung, the tiny emphysema bubble ruptures by itself, and the air in the lung and bronchus escapes into the pleural cavity, which is called spontaneous pneumothorax.
2, it is recommended to go to the hospital to clarify the cause, such as whether it is caused by the most common pulmonary blister, or caused by other diseases of the lung, etiology treatment, so as not to delay the disease.
3.If it is caused by pulmonary herpes.
Pulmonary herpes is caused by congenital abnormal bronchial development, mucosal folds in the form of flaps, and poorly developed cartilage, which causes the role of live flaps. If there are symptoms of chest tightness, shortness of breath, and recurrent, surgery is recommended. If there are no symptoms, it can be observed and treated by internal medicine.
The patient’s symptoms are closely related to the number and size of the macules and whether they are accompanied by inflammation and whether the pulmonary macules rupture.
First of all, small congenital pulmonary blisters usually do not lead directly to death.
However, a large congenital pulmonary blister or the presence of serious complications may cause death. Causes.
1. Direct cause. In large pulmonary blisters, there are varying degrees of respiratory distress due to difficulty in gas exchange, and some patients lose their labor force and may even have limited mobility or suffocation.
2.Indirect causes. It is mainly when complications occur. First, the vast majority of congenital pulmonary herpes is not infected, but if the cold and other reasons caused by increased lung secretions, the bronchi draining pulmonary herpes blocked, pulmonary herpes bronchi filled with inflammatory secretions, patients can appear fever, cough, cough and other symptoms of infection, in serious cases can lead to bacteremia, sepsis, septicemia leading to life-threatening. Secondly, spontaneous hemothorax caused by pulmonary blister, mostly bleeding from the pulmonary apical blister or pulmonary tissue around the blister with adhesions and adhesions tearing activity at the apex of the chest. The bleeding is difficult to stop automatically because the blood in the chest cavity does not coagulate due to the defibrotic effect of lung, heart and diaphragm movement. Clinical symptoms may vary depending on the speed of bleeding. When bleeding is slow, patients may show gradually increasing chest tightness, dyspnea, blunted diaphragm angle visible on X-ray, or parabolic images of pleural effusion. When bleeding is rapid, there can be shock manifestation in a short period of time. Third, a large range of congenital pulmonary herpes leads to the body in long-term gas exchange difficulties, hypoxia, can lead to can prompt the occurrence of pulmonary heart disease, and even multi-organ failure.
3, congenital pulmonary blister rupture can also be life-threatening. Rupture can be complicated by spontaneous pneumothorax, with sudden chest pain and difficulty in breathing. If the rupture of the pulmonary herpes forms a live valve, the negative pressure in the chest cavity increases when inhaling, the gas enters the chest cavity, and the live valve closes when exhaling, the gas cannot be discharged, especially when coughing, the airway pressure increases when the vocal valve is closed, the gas enters the chest cavity, the vocal valve opens, the airway pressure decreases, the fissure closes again, and the amount of gas in the chest cavity increases with each breath and cough, forming a tension pneumothorax.
In tension pneumothorax, the lung tissue on the affected side is completely atrophied and the mediastinum is pushed to the healthy side, while the lung tissue on the healthy side is also compressed and the large blood vessels of the heart are displaced and the large veins are distorted and deformed, which affects the blood return flow and causes serious impairment of respiratory circulation. This may lead to rapid cardiopulmonary failure and death.
Complications
(A) Recurrent pneumothorax
About 1/3 of pneumothorax can recur ipsilaterally within 2-3 years. For multiple recurrence of pneumothorax. For those who can tolerate surgery, pleural repair is performed; for those who cannot tolerate dissection, pleural adhesion therapy can be considered. The available adhesion agents are tetracycline powder injection, sterilized refined talc, 50% glucose, vitamin C, pneumonia vaccine, streptococcal kinase, OK432 (streptococcal preparation), etc. Its mechanism of action is to produce sterile metaplastic pleural inflammation through biological and physicochemical stimulation, which causes adhesion of two layers of pleura and atresia of pleural cavity for the purpose of preventing and treating pneumothorax. Before injecting adhesives into the pleural cavity, there should be closed drainage by negative pressure suction to make sure that the lungs are completely reopened. To avoid severe chest pain caused by drugs, appropriate lidocaine should be injected first, and the patient should be allowed to rotate the position to make the pleura fully anesthetized, and adhesives should be injected after 15-20 minutes. If tetracycline powder 0.5-1g is dissolved in 100ml of saline and injected into the chest cavity from the drainage tube, the patient is asked to repeatedly rotate the position so that the drug evenly coats the pleura (especially the lung tip) and the tube is clamped and observed for 24 hours (if there are symptoms of pneumothorax, open the tube at any time to ventilate), the excess drug is sucked out of the chest cavity, if it is not effective at one time, the drug can be repeatedly injected and observed for 2-3 days, and the pneumothorax can be cured by fluoroscopy or radiography, then the tube can be removed. drainage tube.
(II) Pneumothorax
Necrotizing pneumonia, lung abscess and caseous pneumonia caused by Staphylococcus aureus, Pneumococcus pneumoniae, Pseudomonas aeruginosa, Mycobacterium tuberculosis and various anaerobic bacteria can be complicated by pneumothorax. The condition is critical, and bronchopleural fistulas are often formed. Pathogenic bacteria can be found in the pus, and in addition to the appropriate application of antibiotics (local and systemic), surgical treatment should be considered according to the specific situation.
(C) Hemopneumothorax
Spontaneous pneumothorax with intrapleural hemorrhage is due to the cleavage of blood vessels within the pleural adhesion zone. After complete lung reopening, the bleeding can mostly stop on its own. If the bleeding continues, in addition to pumping and draining fluid and appropriate blood transfusion, open chest ligation of the bleeding vessels should be considered.
(IV) Mediastinal emphysema and subcutaneous emphysema
Subcutaneous emphysema of the chest wall may occur along the pinhole or incision after high pressure pneumothorax aspiration or installation of closed drainage. The escaping gas also spreads to the abdominal wall and subcutaneous upper extremities. The high pressure gas enters the interstitial lung, follows the vascular sheath, and enters the mediastinum through the pulmonary hilum. The mediastinal gas may then enter the subcutaneous tissue of the neck and the subcutaneous thoracic abdomen along the fascia, and the subcutaneous and mediastinal marginal hyaline bands can be seen on the X-ray, and the large blood vessels in the mediastinum are compressed. Rupture sounds may be heard in the mediastinal region.
Subcutaneous emphysema and mediastinal emphysema are self-absorbing with decompression of the gas in the pleural cavity. The inhalation of higher oxygen concentration can increase the concentration of oxygen in the mediastinum and facilitate the dissipation of the emphysema. If the tension of mediastinal emphysema is too high and affects breathing and circulation, suprasternal fossa puncture or incision can be made to vent the air.
Pneumothorax is easily confused with which diseases
1, pneumothorax , especially limited or encapsulated pneumothorax should be distinguished from giant pneumothorax.
The two are similar in terms of symptoms, signs and X-ray chest film, but on closer examination, there are indeed differences.
(1) the history of giant pulmonary blister is long and the symptoms occur slowly; while the history of pneumothorax is short and the symptoms often occur suddenly.
(2) The pneumothorax is round or oval in shape and located in the lung field, while the pneumothorax is a banded pneumothorax and located in the pleural cavity outside the chest.
③The upper pulmonary blister is seen to have a downward depression of the basal margin and an upward extension of the lung tissue under the lower margin, while the upper chest wrapped pneumothorax has its outer lower air shadow tilted outward and downward.
④If the pulmonary alveoli are in the lower lobe, the rib-diaphragm angle is rounded and blunt, and the extruded lung tissue and/or pleura can be seen close to the chest wall, with no fluid plane in the pneumothorax. In contrast, fluid planes can be seen at the angle of the rib diaphragm in patients with pneumothorax.
⑤ After a longer period of observation, the size of the pulmonary blister rarely changes, while the pneumothorax form becomes smaller with each passing day and finally disappears.
2.Pneumothorax should be distinguished from myocardial infarction, pulmonary infarction, septal hernia, bronchial asthma, bronchopulmonary cyst and diaphragmatic hernia, chronic obstructive pulmonary emphysema and other diseases: according to medical history, symptoms, signs, combined with chest X-ray, electrocardiogram and related examinations can make the distinction.