Bronchopulmonary dysplasia
Encyclopedia
Bronchopulmonary dysplasia (BPD; formerly Chronic Lung Disease of Infancy) is a chronic lung
disorder that is most common among children who were born prematurely
, with low birthweights and who received prolonged mechanical ventilation
to treat respiratory distress syndrome
. The classic diagnosis of BPD may be assigned at 28 days of life if the following criteria are met (Bureau of Maternal and Child Health, 1989):
(1) Positive pressure ventilation during the first 2 weeks of life for a minimum of 3 days.
(2) Clinical signs of abnormal respiratory function.
(3) Requirements for supplemental oxygen for longer than 28 days of age to maintain PaO2 above 50 mm Hg.
(4) Chest radiograph with diffuse abnormal findings characteristic of BPD.
BPD is characterized by inflammation
and scar
ring in the lungs. More specifically, the high pressures of oxygen delivery result in necrotizing bronchiolitis and alveolar septal injury, further compromising oxygenation of blood. Today, with the advent of surfactant therapy and high frequency nasal ventilation and oxygen supplementation, infants with BPD experience much milder injury without necrotizing bronchiolitis or alveolar septal fibrosis. Instead, there usually are uniformly dilated acini with thin alveolar septa and little or no interstitial fibrosis. It develops most commonly in the first 4 weeks after birth. However, since very preterm infants are at risk of BPD, recent study from Australia found that DHA
supplementation can reduce the BPD incidence and atopic outcomes in preterm infants with gestational age younger than 33 weeks.
Physical findings:
Lung
The lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
disorder that is most common among children who were born prematurely
Premature birth
In humans preterm birth refers to the birth of a baby of less than 37 weeks gestational age. The cause for preterm birth is in many situations elusive and unknown; many factors appear to be associated with the development of preterm birth, making the reduction of preterm birth a challenging...
, with low birthweights and who received prolonged mechanical ventilation
Mechanical ventilation
In medicine, mechanical ventilation is a method to mechanically assist or replace spontaneous breathing. This may involve a machine called a ventilator or the breathing may be assisted by a physician, respiratory therapist or other suitable person compressing a bag or set of bellows...
to treat respiratory distress syndrome
Infant respiratory distress syndrome
Infant respiratory distress syndrome , also called neonatal respiratory distress syndrome or respiratory distress syndrome of newborn, previously called hyaline membrane disease, is a syndrome in premature infants caused by developmental insufficiency of surfactant production and structural...
. The classic diagnosis of BPD may be assigned at 28 days of life if the following criteria are met (Bureau of Maternal and Child Health, 1989):
(1) Positive pressure ventilation during the first 2 weeks of life for a minimum of 3 days.
(2) Clinical signs of abnormal respiratory function.
(3) Requirements for supplemental oxygen for longer than 28 days of age to maintain PaO2 above 50 mm Hg.
(4) Chest radiograph with diffuse abnormal findings characteristic of BPD.
BPD is characterized by inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
and scar
Scar
Scars are areas of fibrous tissue that replace normal skin after injury. A scar results from the biological process of wound repair in the skin and other tissues of the body. Thus, scarring is a natural part of the healing process. With the exception of very minor lesions, every wound results in...
ring in the lungs. More specifically, the high pressures of oxygen delivery result in necrotizing bronchiolitis and alveolar septal injury, further compromising oxygenation of blood. Today, with the advent of surfactant therapy and high frequency nasal ventilation and oxygen supplementation, infants with BPD experience much milder injury without necrotizing bronchiolitis or alveolar septal fibrosis. Instead, there usually are uniformly dilated acini with thin alveolar septa and little or no interstitial fibrosis. It develops most commonly in the first 4 weeks after birth. However, since very preterm infants are at risk of BPD, recent study from Australia found that DHA
Docosahexaenoic acid
Docosahexaenoic acid is an omega-3 fatty acid that is a primary structural component of the human brain and retina. In chemical structure, DHA is a carboxylic acid with a 22-carbon chain and six cis double bonds; the first double bond is located at the third carbon from the omega end...
supplementation can reduce the BPD incidence and atopic outcomes in preterm infants with gestational age younger than 33 weeks.
Complications
Feeding problems are common in infants with BPD, often due to prolonged intubation. Such infants often display oral-tactile hypersensitivity (also known as oral aversion).Physical findings:
- hypoxemia;
- hypercapnia;
- crackles, wheezing, & decreased breath sounds;
- increased bronchial secretions;
- hyperinflation;
- frequent lower respiratory infections;
- delayed growth & development;
- cor pulmonale;
- CXR shows with hyperinflation, low diaphragm, atelectesis, cystic changes.