Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content +++ Key Features ++ Defined as incomplete development of one or both lungs Characterized by a reduction in alveolar number and a reduction in airway branches Present in up to 10–15% of perinatal autopsies Congenital diaphragmatic hernia is the most common cause, with an incidence of 1:2200 births Can be a result of An intrathoracic mass, resulting in lack of space for the lungs to grow Decreased size of the thorax Decreased fetal breathing movements Decreased blood flow to the lungs Primary mesodermal defect affecting multiple organ systems Other causes include Extralobar sequestration Diaphragmatic eventration or hypoplasia Thoracic neuroblastoma Fetal hydrops Fetal hydrochylothorax Chest cage abnormalities, diaphragmatic elevation, oligohydramnios, chromosomal abnormalities, severe musculoskeletal disorders, and cardiac lesions may also result in hypoplastic lungs +++ Clinical Findings ++ Clinical presentation is highly variable and related to the severity of hypoplasia as well as associated abnormalities Often associated with pneumothorax in newborns Presenting symptoms in some newborns with primary hypoplasia (without associated anomalies) Perinatal stress Severe acute respiratory distress Persistent pulmonary hypertension In lesser degrees of hypoplasia, presenting symptoms may be Chronic cough Tachypnea Wheezing Recurrent pneumonia +++ Diagnosis ++ Chest radiography Findings include variable degrees of volume loss in a small hemithorax with mediastinal shift Pulmonary agenesis should be suspected if tracheal deviation is evident Chest CT scan is the optimal diagnostic method if the chest radiograph is not definitive Ventilation-perfusion scans, angiography, and bronchoscopy may demonstrate decreased pulmonary vascularity or premature blunting of airways associated with the maldeveloped lung tissue Arterial blood gas analysis determines degree of respiratory impairment +++ Treatment ++ Supportive Your MyAccess profile is currently affiliated with '[InstitutionA]' and is in the process of switching affiliations to '[InstitutionB]'. Please click ‘Continue’ to continue the affiliation switch, otherwise click ‘Cancel’ to cancel signing in. Get Free Access Through Your Institution Learn how to see if your library subscribes to McGraw Hill Medical products. Subscribe: Institutional or Individual Sign In Username Error: Please enter User Name Password Error: Please enter Password Forgot Username? Forgot Password? Sign in via OpenAthens Sign in via Shibboleth