lung damage
Introduction
Introduction to lung injury Lung injury is a thoracic surgery disease. The lung is relatively easy to tolerate penetrating damage (except for high-speed projectiles). The lung parenchyma has a good ability to repair. Unless the hilar structure is damaged, the general lung tissue leaks and hemorrhage is very good. It will stop soon, and the parenchymal damage of the surrounding part rarely needs to be removed. On the other hand, although the blunt lung injury causes a small degree of local damage, it can lead to a large area of multiple damage and secondary reactive changes. More serious and even life-threatening complications. basic knowledge The proportion of illness: 0.001% - 0.008% Susceptible people: no special people Mode of infection: non-infectious Complications: lung abscess, mediastinal emphysema, pneumothorax
Cause
Cause of lung injury
A variety of clinical diseases can cause ALI, from the primary lung can be divided into intrapulmonary factors (direct damage) and extrapulmonary factors (indirect damage). According to the ALI/ARDS diagnostic criteria proposed by the 1994 European and American Joint Conference, the incidence of ALI and ARDS in the United States in 2005 was 79/100,000 and 59/100,000 respectively. The incidence of ARDS is different depending on the cause. The incidence of ALI/ARDS can be as high as 25% to 50% in severe infections, 40% in large blood transfusions, and 11% to 25% in multiple traumas. The incidence of ALI/ARDS is further increased when there are two or three risk factors. In addition, the longer the duration of risk factors, the higher the incidence of ALI/ARDS, and the prevalence of ARDS was 76%, 85% and 93%, respectively, at 24, 48 and 72 h.
Although different studies have reported a large difference in ALI/ARDS mortality (15-72%), overall the mortality rate of ARDS is still high. A meta-analysis of 72 ARDS clinical studies officially published in 1994-2006 was conducted, and the mortality rate of 11426 patients with ALI/ARDS was 43%. 15 adult ICUs in Shanghai, China From March 2001 to March 2002, the mortality rate of ARDS was as high as 68.5%. Recently, the meta-analysis of Ritesh A et al. suggests that there is no difference in the mortality rate between ALI and extra-pulmonary factors.
Prevention
Lung injury prevention
There is no effective preventive measure for this disease. Early detection and early diagnosis are the key to the prevention and treatment of this disease. Eating foods rich in quality protein. In a sense, protein is the material basis that determines the immunity of our body. If an adult lacks protein, it will cause physical decline, mental retardation, fatigue, premature aging, prone to illness, loss of elasticity and luster of the skin; To prevent pneumonia, in the daily diet, if you can pay attention to eating foods rich in high-quality protein, such as lean meat, crabs, sea fish, dairy products, soy products, eggs, etc., to improve the body's immunity, from Invasion of foreign pathogens.
Complication
Lung injury complications Complications, lung abscess, mediastinal emphysema, pneumothorax
Shortly after the illness of the patient, after several days or weeks, when the condition has not been alleviated, complications of other organs may occur due to insufficient oxygen supply. Excessive time of hypoxia can cause serious complications such as renal failure. If not treated promptly, it can die due to severe hypoxia. Due to the low ability of patients with acute respiratory distress syndrome to prevent lung infections, bacterial pneumonia often occurs during their illness. Chest complications such as abscesses, mediastinal emphysema and pneumothorax.
Symptom
Symptoms of lung injury Common symptoms Shortness of breath, wet lung, dyspnea, chest pain, alveolar rupture, hemoptysis, hypothermia, severe acute respiratory syndrome, lung consolidation
Lung injury has various manifestations, and clinical classification is artificial because they often appear together. In addition, in addition to lung blast injury, lung parenchymal damage caused by non-penetrating injury often incorporates damage to the internal organs.
1, local lung contusion
This is the most common type of lung injury. Since the blood flowing out of the ruptured blood vessels is filled with the alveoli and the surrounding interstitial lung, the clinical manifestations are hemoptysis and shortness of breath. It is only an isolated injury and has no important clinical significance, even if the blood flows in. In the bronchi, the lung tissue in the distal segment is solidified. If there is no major pulmonary parenchymal rupture, the blood clot is quickly absorbed and the lungs are re-expanded.
2, lung parenchymal tear
The rupture of blood vessels and bronchus, such as communicating with the pleural cavity, can cause hemothorax, pneumothorax or blood pneumothorax. Blood pneumothorax is most common in penetrating injury, while lung parenchymal tear caused by blunt injury is mostly in the deep part. The congestion and gas accumulate in somewhere, not forming a hematoma or an air cavity.
3, pulmonary hematoma
Pulmonary hematoma is caused by the accumulation of blood stasis caused by lung parenchymal tear after lung contusion. It is a common complication of blunt chest injury. The clinical manifestation is chest pain, moderate. Hemoptysis, low fever and difficulty in breathing, usually relieved after 1 week. The pulmonary hematoma is on the initial chest X-ray. The contour of the shadow is blurred. After a few days, the blood around it is absorbed, the outline is distinct, usually located in the big The posterior segment of the leaf, 2 to 5 cm in diameter, the special position of the pulmonary hematoma, which makes people think that the pulmonary hematoma caused by blunt injury is caused by the reaction mechanism in the deep part of the lung parenchyma, such as the premature X-ray chest. In contrast, small pulmonary hematoma is difficult to distinguish from the original spherical lesions of the lung. This question remains to be resolved if the shadow of the lesion disappears quickly. If the shadow is not absorbed within 3 weeks, the biopsy should be considered to confirm the diagnosis.
4, traumatic lung cavity
The lung cavity is rare. If the chest injury only tears a small bronchiole, and there is no damage to the blood vessels, the air accumulates in the deep part of the body, forming an air cavity. Generally, there is no secondary infection, and it will resolve itself within 1 week. Occasionally, if there is a thick bronchial rupture, forming an atmospheric cavity, it is difficult to subside. It is necessary to surgically suture the stump of the bronchus, control the source of the gas, collapse the air cavity, and relieve the compression of the surrounding lung tissue.
Examine
Lung injury examination
1. Laboratory inspection:
The total number and classification of white blood cells are normal and increase with secondary infection.
2, imaging examination:
(1) Early radiation pneumonitis: changes in pulmonary congestion and exudation in the early stage of radiotherapy, increased texture and small patches in the corresponding parts of the radiation, the edges are blurred, and gradually merge with each other in severe cases.
(2) Pulmonary fibrosis: Radiation pneumonitis occurred in the radiation area, and some were absorbed by the treatment, but some patients showed obvious fibrosis in the later stage. The lungs in the radiation area were coarse and dense, the fibers contracted, and the adjacent tissues were displaced.
Diagnosis
Diagnosis and identification of lung injury
diagnosis
According to clinical manifestations, examinations, etc. can be diagnosed.
Differential diagnosis
1, cardiogenic pulmonary edema (left heart failure)
Acute respiratory distress syndrome is a non-cardiogenic pulmonary edema caused by alveolar capillary membrane damage and increased vascular permeability, and therefore must be differentiated from cardiogenic pulmonary edema caused by factors such as increased hydrostatic pressure. Cardiogenic pulmonary edema is common in left heart failure caused by hypertensive heart disease, coronary heart disease, cardiomyopathy, and left atrial failure caused by mitral stenosis. They all have a history of heart disease and corresponding clinical manifestations, such as combined with chest X-ray and electrocardiogram, the diagnosis is generally not difficult. Cardiac catheter pulmonary capillary wedge pressure (Paw) increases in left heart failure (Paw > 2.4 kPa), which is more meaningful for diagnosis.
2, acute pulmonary embolism
More common in post-operative or long-term bedridden, thrombosis from the deep veins of the lower extremities or pelvic veins. The onset of the disease is sudden, with difficulty in breathing, chest pain, hemoptysis, cyanosis, PaO2 decline, etc., and ARDS is not easy to identify. Increased blood lactate dehydrogenase, abnormal ECG (typically SQT changes), radionuclide lung ventilation, perfusion scan and other changes have a greater significance for the diagnosis of pulmonary embolism. Pulmonary angiography is more important in the diagnosis of pulmonary embolism.
3, severe pneumonia
Severe pulmonary infections including bacterial pneumonia, viral pneumonia, and miliary tuberculosis can cause ARDS. However, some patients with severe pneumonia (especially Legionella pneumonia) have clinical manifestations of dyspnea, hypoxemia and the like, but no ARDS. Most of them have large infiltrative inflammation shadows in the lung parenchyma, and the symptoms of infection (fever, increased white blood cells, left shift of the nucleus) are obvious, and sensitive antibiotics can be cured.
4. Idiopathic pulmonary interstitial fibrosis
Some patients with idiopathic pulmonary fibrosis develop subacute and have type II respiratory failure, especially when the lung infection is aggravated, which may be confused with ARDS. The chest auscultation of this disease has Velcro voice, chest X-ray examination is reticular, nodular shadow or accompanied by honeycomb changes, the course of disease development is relatively slower than ARDS, lung function is limited ventilatory disorder can be identified.
