Bronchopulmonary dysplasia (BPD) is a chronic lung condition primarily affecting infants born prematurely. It involves the abnormal development and injury of delicate lung tissue, altering the structure and function of their respiratory system.
Understanding Bronchopulmonary Dysplasia
BPD is a chronic lung disease in premature infants, often leading to long-term breathing difficulties. It impacts the developing lungs by causing irritation and hindering their normal growth. In severe instances, the lungs can exhibit scarring and inflammation, disrupting their ability to function properly.
It affects the tiny air sacs, known as alveoli, and the small airways within the lungs. BPD can lead to damaged or underdeveloped alveoli. This interrupts normal lung architecture, resulting in fewer and larger alveoli, along with a thickening of the interstitial tissue.
It also influences the pulmonary vasculature, where blood vessels may develop abnormally. This can make blood passage through the lungs more challenging and potentially lead to increased pressure within these vessels, a condition called pulmonary hypertension.
Factors Contributing to BPD
BPD develops when premature babies, whose lungs are not fully mature, require breathing assistance. A primary risk factor is extreme prematurity, particularly in infants with very low birth weight. Their undeveloped lungs are susceptible to damage and inflammation.
Respiratory support, such as mechanical ventilation and oxygen therapy, can contribute to lung injury. High amounts of inhaled oxygen and pressure from ventilation can overstretch the alveoli, causing inflammation and damage to the delicate lining of the airways and air sacs. This damage is particularly impactful on the premature lung, which is less resilient than a full-term lung.
Other factors include inflammation within the lungs and infections like pneumonia. These conditions can worsen irritation and swelling in the undeveloped lung tissue, compromising its ability to grow and function normally.
Identifying and Diagnosing BPD
Identifying BPD involves observing specific clinical signs. Infants with BPD often exhibit rapid or difficult breathing, shortness of breath, and visible retractions, which are the pulling in of the skin between the ribs or collar bones during inhalation. Wheezing, grunting while breathing, and persistent dependence on supplemental oxygen are also common indicators.
The diagnosis of BPD is based on the prolonged need for oxygen supplementation. Medical professionals consider BPD present if an infant requires supplemental oxygen beyond 28 days of age or after 36 weeks postmenstrual age. This criterion helps distinguish BPD from other conditions requiring oxygen support.
Supporting diagnostic tests include chest X-rays, which can reveal characteristic changes in lung appearance, such as hyperinflation, a low diaphragm, and sometimes cystic changes or atelectasis. These imaging findings, combined with observed clinical symptoms and the infant’s history of prematurity and respiratory support, help confirm the diagnosis.
Managing BPD and Long-Term Outlook
Managing BPD involves supportive care to promote lung healing and overall development. Nutritional support is a significant component, as adequate growth is linked to better lung recovery. Infants with BPD often have increased calorie needs due to the extra effort required for breathing.
Medications are used to manage symptoms and support lung function. Diuretics may be prescribed to reduce fluid in the lungs, while bronchodilators can help open airways. In some instances, steroids might be considered to reduce inflammation, although their use is carefully weighed due to potential side effects.
Ongoing respiratory support, ranging from supplemental oxygen to non-invasive ventilation, is often necessary as the infant’s lungs mature. While many children with BPD show significant improvement in their breathing difficulties over time, some may experience long-term respiratory issues, such as asthma-like symptoms or increased susceptibility to respiratory infections. Some children may also face developmental challenges, necessitating ongoing follow-up care and therapies.