Bronchopulmonary hypoplasia in children
Introduction
Brief introduction of bronchopulmonary hypoplasia in children Bronchopulmonary dysplasia (BPD) is a chronic lung injury caused by a variety of factors, which occurs in immature children and patients with hyaline membrane disease after high concentration of oxygen and mechanical ventilation, and its main pathological changes For pulmonary fibrosis, it is also known as ventilator lung or fibroproliferative chronic lung disease, now also known as chronic lung disease (CLD), some scholars will BPD, Wilson-Mikity syndrome and chronic immature lung insufficiency (chronicpulmonaryinsufficiencyofprematurity, CPIP) is considered as three types of CLD, a chronic lung disease following neonatal lung injury. basic knowledge The proportion of the disease: 0.001% - 0.002% (the above is the incidence of infants and young children) Susceptible people: children Mode of infection: non-infectious Complications: Asthma Pulmonary heart disease Respiratory failure
Cause
Causes of bronchopulmonary dysplasia in children
(1) Causes of the disease
The cause has not been fully understood so far, and the causes of BPD may be induced:
1. High concentration of oxygen.
2. Mechanical positive pressure ventilation damage.
3. Chronic inflammation.
4. Excessive water and salt intake, that is, too much infusion.
5. Arterial catheter closure with heart failure.
6. Lung maturity is poor.
7. Asphyxiation during production, the disease can be seen in full-term newborns with meconium inhalation, persistent pulmonary hypertension, congenital cardiopulmonary disease, intracranial hemorrhage or septic shock after mechanical ventilation treatment, some scholars inhaled high concentrations of oxygen in newborn lambs, Regardless of whether mechanical ventilation can cause similar BPD changes, it is believed that chronic pulmonary edema caused by any cause can hinder lung development after birth of immature lungs. Recently, gastroesophageal reflux has been reported to delay the course of bronchopulmonary dysplasia.
(two) pathogenesis
1. High concentration of oxygen: It has been reported that after inhaling high concentration of oxygen, intermediate metabolites of oxygen in the body such as peroxide, free radicals, hydroxyl ions, hydrogen peroxide, and singlet oxygen are highly active free radicals. Oxidized cell membrane unsaturated lipids and intracellular thiolase, glutathionease, coenzyme A, etc., interfere with cell metabolism, thereby impairing its structure, while the cilia activity of epithelial cells disappears after high concentration of oxygen, and mucus accumulates in After the lungs, epithelial cells are xenobiotic and degenerate, leading to chronic lung lesions.
2. Barotrauma: Positive pressure, inspiratory peak pressure is too high, excessive inspiratory time, excessive lung expansion, can produce bronchopulmonary dysplasia.
3. Premature delivery: Insufficient antioxidant enzyme system in premature infants, sensitive to oxygen; premature infants are prone to hyaline membrane disease in the lungs, need mechanical ventilation, due to high airway resistance, decreased lung compliance, artificial ventilation easily lead to alveolar, small bronchi Injury; premature infants are prone to patent ductus arteriosus, leading to pulmonary edema; premature infants with vitamin A, vitamin E deficiency.
4. Other factors: Chronic inflammation of the lungs, asphyxia at birth, excessive water and salt input, chronic pulmonary edema caused by heart failure due to congenital heart disease, hinder the development of lungs after birth, and promote the occurrence of BPD.
Prevention
Prevention of bronchopulmonary hypoplasia in children
In addition to measures to prevent premature delivery and hyaline disease, it should be noted that in the rescue of neonatal respiratory failure, the oxygen concentration should not be too high, the pressure during mechanical ventilation should not be too large to avoid lung injury, pay attention to avoid excessive sodium and water, timely correction of patent ductus arteriosus and Proper antibiotics to prevent infection, etc., it has been reported that vitamin E can reduce the occurrence of BPD, but there is no conclusion, in addition, hunger, protein, vitamins, trace element deficiency, etc., can increase the oxygen toxicity of the lung, should be noted.
Complication
Pediatric bronchopulmonary dysplasia complications Complications, asthma, pulmonary heart disease, respiratory failure
Asthma, pulmonary heart disease, pulmonary dysfunction, pulmonary infection, respiratory failure, etc. Survivors often have poor growth and development, chronic asthma, pulmonary fibrosis, pulmonary dysfunction, pulmonary heart disease and neurological complications such as mental retardation, cerebral palsy, etc. .
Symptom
Symptoms of bronchopulmonary hypoplasia in children Common symptoms Pale hypoxemia, dryness, cough, shortness of breath, snoring, wheezing, drowsiness, three concave signs, jugular vein engorgement
For premature infants with hyaline membrane disease or after prolonged unhealed or improved, respiratory distress and hypoxia, pale, sweating, lethargy, vomiting, dry cough, shortness of breath, cyanosis, difficulty breathing, mild intercostal space depression, lung There are wet voices and wheezing sounds, there are apnea episodes, need oxygen and assisted ventilation, the course of disease is prolonged for several weeks to several months, there is progressive respiratory failure and heart failure, often with right heart failure, such as liver enlargement, distal end Edema, jugular vein engorgement, etc., arterial blood gas analysis can be found with hypoxemia and (or) hypercapnia, clinically visible growth retardation or stagnation in children, recovery patients often have repeated lower respiratory tract in 1 to 2 years old Infection, dependence on oxygen and respirator survival.
Examine
Examination of bronchopulmonary hypoplasia in children
In the first stage of tracheal secretion cytology, squamous epithelial cells and shrunken cells, a small number of fibroblasts, phase II saw a large number of squamous epithelial cells and some immature cells, and stage III and IV showed degenerative cells and exfoliated respiratory tract. Mucosal tube type.
1. X-ray examination: It is difficult to distinguish from RDS, it can be divided into 4 stages, stage I: more common double lung field density increase shadow, there are extensive particle shadow and bronchial aeration sign, phase II: double lung transmittance almost disappears, heart Enlargement, blurred heart, stage III: lung field is diffuse small round honeycomb translucent area, irregular density, plum-like shape, stage IV: about 1 month after onset, the dense lungs see dense striped changes, and See the irregular translucent area.
2. Pulmonary function test: Lung activity is the most sensitive indicator, with increased airway resistance and decreased lung compliance.
Diagnosis
Diagnosis and diagnosis of bronchopulmonary hypoplasia in children
diagnosis
1. History: 50% occur in premature infants with a birth weight <1000g, most commonly seen in hyaline membrane disease, especially complicated with PDA, barotrauma and pneumonia.
2. Clinical manifestations: The clinical can be divided into 4 phases: the first phase (the first 2 to 3 days): for the acute respiratory distress phase, there are obvious dyspnea and cyanosis, and the respiratory distress can not be distinguished from the primary disease, phase II (4 to 10 days): There is very little inflation in the lungs, the lungs become hard, the lung compliance decreases, the difficulty of breathing and the cyanosis are further aggravated, and pneumothorax, mediastinal emphysema, and children often die in this period, Phase III (10 30 days): In the transition to the chronic phase, the lungs began to show proliferative changes. At this time, the condition was relatively stable, but due to hypoxemia and hypoventilation, the children were still inseparable from oxygen and needed a respirator. Stage IV (1 month later): for the chronic phase, there is extensive interstitial fibrosis and lung tissue destruction, which can be manifested as progressive respiratory failure, development of pulmonary heart disease, slow growth, stagnation, shortness of breath accompanied by three Concavity sign, there are blisters and wheezing sounds in the lungs, often leading to death from respiratory infections. The mortality rate in this period is about 40%. About one-third of the survivors and the X-ray lungs gradually return to normal after 3 years. .
Differential diagnosis
1.Wilson-Mikity syndrome: Some scholars believe that the second disease is one, but more scholars believe that it is two diseases, although both are prone to premature infants, and X-rays are very similar, but Wilson-Mikity syndrome is mainly It is related to the immature lung, generally no hyaline disease and inhalation of high concentration of oxygen and mechanical ventilation injury history; it is completely normal a few days after birth, more than 1 to 3 weeks after birth, symptoms appear, the onset is hidden, X-ray appears In the third phase of BPD, diffuse interstitial infiltration with small cystic transparent area, in addition to common rib fractures, has been rare in recent years.
2. Cytomegalovirus infection and Cysticercus cellulosae: See related content.
3. Cystic fibrosis: See related content, in addition to the identification of various pneumonia, pulmonary hemorrhage and pulmonary edema.
