Bronchopulmonary dysplasia in premature infants

Among all the pathologies in children who were born earlier than the prescribed time, breathing problems are especially common. They are diagnosed in 30-80% of premature babies. During their treatment, oxygen is used, which provokes the appearance of another pathology - bronchopulmonary dysplasia (BPD).

Causes

The high frequency of problems with the respiratory system in premature babies is due to the fact that such babies do not have time to mature the surfactant system. TThis is the name of the substances that cover the alveoli of the lungs from the inside and prevent them from sticking together during exhalation. They begin to form in the lungs of the fetus from 20-24 weeks of gestation, but completely cover the alveoli only by 35-36 weeks. During childbirth, the surfactant is synthesized especially actively so that the lungs of the newborn immediately expand and the baby begins to breathe.

In premature babies, such a surfactant is not enough, and many pathologies (asphyxia during childbirth, diabetes in a pregnant woman, chronic fetal hypoxia during gestation, and others) inhibit its formation. If the baby develops a respiratory tract infection, the surfactant is destroyed and inactivated.

As a result, the alveoli do not expand and collapse insufficiently, which causes lung damage and impairment of gas exchange. To prevent such problems, the baby is given artificial lung ventilation (ALV) immediately after birth. A complication of this procedure, in which oxygen is used at a high concentration, is bronchopulmonary dysplasia.

In addition to insufficient lung maturity in premature infants and toxic exposure to oxygen, factors that trigger BPD are:

Lung tissue barotrauma during mechanical ventilation.
Incorrect surfactant administration.
Hereditary predisposition.
The ingestion of infectious agents into the lungs, among which the main ones are called chlamydia, ureaplasma, cytomegalovirus, mycoplasma and pneumocystis. The pathogen can enter the baby's body in utero or as a result of tracheal intubation.
Pulmonary edema, which can be caused both by problems with the removal of fluid from the baby's body, and by an excess volume of intravenous infusions.
Pulmonary hypertension, which is often caused by heart defects.
Aspiration of stomach contents due to gastroesophageal reflux during mechanical ventilation.
Lack of vitamins E and A.

Symptoms

The disease manifests itself after the infant is disconnected from mechanical ventilation. The child's breathing rate increases (up to 60-100 times per minute), the baby's face turns blue, a cough appears, during breathing, the gaps between the ribs are drawn in, the exhalation becomes longer, and a whistle is heard when breathing.

If the disease is difficult, the child cannot be removed from the apparatus at all, as he immediately suffocates.

Diagnostics

To detect bronchopulmonary dysplasia in an infant born prematurely, one should consider:

Anamnesis data - at what stage of pregnancy the baby was born and with what weight, whether there was mechanical ventilation, what was its duration, whether there is oxygen dependence.
Clinical manifestations.
Results of X-ray and blood gas analysis, as well as computed tomography of the chest.

BPD forms

Depending on the severity and the baby's need for oxygen, they emit:

Mild bronchopulmonary dysplasia - respiratory rate up to 60, at rest breathing is not rapid, mild shortness of breath and symptoms of bronchospasm appear with a respiratory infection.
Moderate BPD - respiratory rate 60-80, increases with crying and feeding, moderate shortness of breath, dry wheezing is determined on exhalation, if an infection joins, the obstruction increases.
A severe form - the respiratory rate is more than 80 even at rest, the symptoms of bronchial obstruction are pronounced, the child lags behind in physical development, there are many complications from the lungs and heart.

During the course of the disease, there are periods of exacerbation, which are replaced by periods of remission.

BPD stages

The first stage of the disease begins on the second or third day of the baby's life. It is manifested by shortness of breath, tachycardia, blue skin, dry cough, rapid breathing.
From the fourth to the tenth day of life, the second stage of the disease develops, during which the epithelium of the alveoli is destroyed, and edema appears in the lung tissue.
The third stage of the disease begins from the 10th day of life and lasts on average up to 20 days. It damages the bronchioles
From the 21st day of life, the fourth stage develops, during which areas of collapsed lung tissue appear in the lungs, and emphysema also develops. As a result, the child develops chronic obstructive disease.

Treatment

In the treatment of BPD, the following are used:

Oxygen therapy. Although the disease is provoked by mechanical ventilation, a child with dysplasia often requires long-term oxygen supply. With this treatment, the oxygen concentration and pressure in the apparatus are maximally reduced. In addition, the amount of oxygen in the baby's blood must be monitored.
Diet therapy. The baby should receive food at the level of 120-140 kcal for each kilogram of his weight per day. If the condition of the baby is severe, nutrient solutions (fat emulsions and amino acids) are administered intravenously or through a tube. The liquid is given in moderation (up to 120 ml per kilogram of body weight per day) to eliminate the risk of pulmonary edema.
Mode. The baby is provided with peace and optimal air temperature.
Medicines. Babies with BPD are prescribed diuretics (prevent pulmonary edema), antibiotics (prevent or eliminate infection), glucocorticoids (relieve inflammation), bronchodilators (improve bronchial patency), heart medications, vitamins E and A.

Potential consequences and complications

With a moderate and mild course of the disease, the condition of babies is slowly (within 6-12 months) improving, although BPD proceeds with fairly frequent episodes of exacerbations. A severe form of dysplasia in 20% of cases leads to the death of the baby. In surviving infants, the disease lasts for many months and may result in clinical improvement.

In some children born prematurely, the diagnosis remains for life and becomes the cause of disability.

Common complications of BPD are:

The formation of atelectasis, which are collapsed areas of lung tissue.
The appearance of cor pulmonale. This is the name of the lung changes caused by vasoconstriction in the right ventricle.
The development of heart failure associated with an enlarged heart.
Formation of chronic respiratory failure, in which the child is required to additionally give oxygen after discharge at home.
Development of bronchial infections and pneumonia. They are especially dangerous for children under 5-6 years old, as they often lead to death.
The appearance of bronchial asthma.
Increased risk of sudden infant death syndrome due to frequent and prolonged sleep apnea.
Increased blood pressure. Usually diagnosed in a child of the first year of life and is often successfully treated with antihypertensive drugs.
Delayed development. In babies, a low rate of weight gain is noted, and growth retardation, and a lag in neuropsychic development caused by brain damage during periods of hypoxia.
The appearance of anemia.

Prevention

The most important preventive measures for BPD are preventing premature birth and proper care of the premature baby. A woman expecting a baby should:

Treat chronic diseases in a timely manner.
Eat well.
Avoid smoking and alcohol.
Avoid strenuous physical activity.
Provide psycho-emotional peace.

If there is a threat of premature birth, glucocorticoids are prescribed to the expectant mother to accelerate the synthesis of surfactant and more rapid maturation of the alveoli in the fetal lungs.

A baby who was born ahead of schedule needs: