A baby with a giant omphalocele is born at 33 weeks gestation with a birth weight of 1800 gm. They have respiratory distress requiring intubation and mechanical ventilation. What is the most likely cause of respiratory morbidity in this baby with giant omphalocele?

 

a pneumonia and sepsis

 

b pulmonary hypoplasia

 

c hyaline membrane disease

 

d meconium aspiration

 

e associated congenital diaphragmatic hernia

B

B

A baby with a giant omphalocele is born at 33 weeks gestation with a birth weight of 1800 gm. They have respiratory distress requiring intubation and mechanical ventilation. What is the most likely cause of respiratory morbidity in this baby with giant omphalocele?

 

a pneumonia and sepsis

 

b pulmonary hypoplasia

 

c hyaline membrane disease

 

d meconium aspiration

 

e associated congenital diaphragmatic hernia

B

e

A baby with a giant omphalocele is born at 33 weeks gestation with a birth weight of 1800 gm. They have respiratory distress requiring intubation and mechanical ventilation. What is the most likely cause of respiratory morbidity in this baby with giant omphalocele?

 

a pneumonia and sepsis

 

b pulmonary hypoplasia

 

c hyaline membrane disease

 

d meconium aspiration

 

e associated congenital diaphragmatic hernia

B

B

correct answer

b pulmonary hypoplasia

 

Babies born with giant omphalocele often have associated pulmonary hypoplasia which can cause respiratory distress at birth, complicate attempts to surgically repair the omphalocele and be an important determinant of long term outcome. The pulmonary hypoplasia may be the result of deformation of the chest wall associated with the abdominal wall defect and the liver displacement seen in giant omphaloceles. The resulting narrow chest is a characteristic finding that can be seen on pre- and postnatal imaging. Prenatal imaging measurements are being used to predict the severity of pulmonary hypoplasia and postnatal morbidity and mortality. Patients with giant omphalocele and pulmonary hypoplasia should also be screened for pulmonary hypertension. The presence of pulmonary hypertension is associated with increased duration of mechanical ventilation, longer length of hospitalization, and higher mortality.

 

Diaphragm defects are present in one to two percent of patients with omphalocele and when present are often anterior or anterolateral defects rather than the posterolateral defects seen in babies with congenital diaphragmatic hernia not associated with omphalocele. The risk of respiratory distress syndrome caused by surfactant deficiency is directly related to the degree of prematurity. Although 40% of babies with omphalocele are born prematurely, respiratory distress syndrome would be very uncommon in a baby of 35 weeks gestation. Meconium aspiration is also possible but is more commonly seen in babies who are born after their due date. Sepsis is also possible but there are no risk factors for neonatal sepsis noted in the case presented (e.g. prolonged rupture of membranes, maternal fever or uterine tenderness, inadequately treated maternal group B Strep colonization).