CASE PRESENTATION
A female neonate, born at 39 weeks, with no prenatal complications was born to a healthy 27-year-old mother by spontaneous vaginal delivery. The baby had Apgar scores of 8 and 9. However, shortly after birth, the patient developed hypoxia. She was tachypneic (RR 60s-70s) and required oxygen via nasal cannula to maintain adequate oxygen saturations. A chest x-ray was performed and read as right lung collapse with a mass in the right hemithorax.
WHAT IS YOUR DIAGNOSIS?
A. Pleural effusion
B. Dextrocardia with cardiomegaly
C. Right-sided congenital diaphragmatic hernia (CDH)
D. Pulmonary hamartoma
THE DIAGNOSIS IS:
C. right-sided CDH
CASE PROGRESSION
The infant was transferred to a larger hospital for further workup. A computed tomography scan revealed agenesis of the right lung with abdominal viscera in the right hemithorax. Most of the right hepatic lobe and right kidney were herniated through a right-sided diaphragmatic hernia.
RESOLUTION OF THE CASE AND PATIENT OUTCOMES
Pediatric surgery was consulted for surgical repair of the hernia. However, they deferred treatment because of futility, as there was no viable right lung. Surprisingly, the neonate became clinically stable. She appeared comfortably tachypneic with a respiratory rate in the 40s-50s and was able to maintain oxygen saturations of 100% with supplemental O2 via nasal cannula. She was discharged home on 0.1-L oxygen at 100% FiO2 with plans to follow up with a pediatric pulmonary specialty clinic.
INFORMATION ABOUT THE DIAGNOSIS
CDHs are structural defects in the skeletal muscle that separate the thoracic and abdominal cavities (Kardon et al., 2017). These defects impair respiration as well as allow the contents of the abdominal cavity to herniate into the thoracic cavity, which disrupts lung and pulmonary vascular development (Kardon et al., 2017). The cause of CDH is unknown and is likely multifactorial. CDH has been associated with specific genetic mutations in about 30% of cases (Kardon et al., 2017). The size and location of CDHs vary, with posterolateral defects most likely to be associated with pulmonary hypoplasia (Kardon et al., 2017).
CDH is a birth defect with high morbidity and mortality. However, treatments are improving, and the survival rate for infants with CDH is now over 70% (Putnam et al., 2016). Treatment most often consists of gentle ventilatory support until the neonate is stabilized, followed by surgical repair of the hernia. Gentle ventilatory support uses small tidal volumes and low peak inspiratory pressures, with permissive hypercapnia to prevent barotrauma to the lung tissue (Bhatnagar & Sarin, 2017). Some patients require extracorporeal membrane oxygenation.
A prenatal treatment option, which may be tried in severe cases diagnosed before birth, is fetal endoscopic tracheal occlusion. In fetal endoscopic tracheal occlusion, a balloon is inserted into the trachea of the fetus at 26-28 weeks of gestation, which blocks fluid produced in the lungs from escaping and promotes stretch and growth of the lungs (Kardon et al., 2017).
Pulmonary hypertension is a severe complication of CDH, before and after repair. Blood flow is reduced through the pulmonary arteries, causing hypoxemia, which can lead to right heart failure. There are many medications used to treat pulmonary hypertension; however, some patients do not respond to medical therapy (Bhatnagar & Sarin, 2017).
Right-sided defects occur in about 25% of all CDH cases (Partridge et al., 2016). There is an increased incidence of postnatal diagnosis of CDH with right-sided defects, possibly related to diagnostic challenges involving the similarity of the fetal liver and lung on sonography as well as the lower incidence of right-sided CDH (Partridge et al., 2016). A retrospective study by Partridge et al. (2016) found no difference in mortality rates between right- versus left-sided CDH. However, pulmonary morbidities, such as pulmonary hypoplasia and pulmonary hypertension, are associated with greater mortality and are more highly associated with right-sided defects (Partridge et al., 2016).
A retrospective study by Putnam et al. (2016) found that the size of the hernia seems to be the greatest predictor of the quality of outcome and burden of disease for patients with CDH. Many patients with CDH will require pulmonary medications, such as pulmonary vasodilators, and/or supplemental oxygen at discharge (Putnam et al., 2016). Patients with CDH often have comorbidities including gastroesophageal reflux, failure to thrive, and neurodevelopmental delay.
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