Respiratory distress, the most common indication for neonatal intensive care, manifests with 1 or more of the following: tachypnea, grunting, nasal flaring, and chest retractions. In addition, the infant may also have cyanosis, gasping, apnea, stridor, or choking. Conditions that cause respiratory distress in the newborn are listed in Table 52-1.
TABLE 52-1CAUSES OF RESPIRATORY DISTRESS IN THE NEWBORN ||Download (.pdf) TABLE 52-1CAUSES OF RESPIRATORY DISTRESS IN THE NEWBORN
|Respiratory Diseases |
Vocal cord paralysis
2. Chest wall abnormalities/diaphragmatic hernia
3. Malformations of the mediastinum and lung parenchyma
Congenital cystic adenomatoid malformation (CCAM)
Congenital lobar emphysema
Congenital pulmonary cyst
Pulmonary arteriovenous malformations
4. Lung parenchymal and vascular diseases
Transient tachypnea of the newborn
Hyaline membrane disease
Meconium aspiration syndrome
Persistent pulmonary hypertension
Congenital alveolar proteinosis or genetic abnormalities of surfactant system
Tetralogy of Fallot
Transposition of the great vessels
Total anomalous pulmonary venous return
Patent ductus arteriosus
Interrupted aortic arch
Hypoplastic left heart syndrome
Coarctation of the aorta
Severe congestive heart failure
Other Disease Processes
Hypoxic ischemic encephalopathy
TRANSIENT TACHYPNEA OF THE NEWBORN
Transient tachypnea of the newborn (TTN) is a self-limiting, usually benign disease, affecting term or late preterm infants soon after birth. It occurs in approximately 11 infants per 1000 live births and is more common in males. It is associated with cesarean section delivery, the use of analgesia or anesthesia during labor, gestational diabetes, and perinatal asphyxia.
TTN results from inadequate or delayed absorption of fetal lung fluid leading to a persistent postnatal pulmonary edema.
CLINICAL FEATURES AND DIAGNOSIS
Infants with TTN present shortly after birth with mild to moderate respiratory distress. They have mild cyanosis and often require oxygen therapy but rarely need mechanical ventilation. On physical examination, diffuse crackles and rhonchi during the first few hours after birth result from residual fluid within the air spaces of the lungs. Blood gas analysis may be normal or may reveal mild alkalosis and hypoxemia. The characteristic radiographic findings are prominent pulmonary vascular markings, especially around the hila; diffuse parenchymal infiltrates; widened interlobar fissures; and some degree of hyperinflation with flattening of the diaphragm. Pleural effusions may also be present and the cardiac silhouette may appear enlarged on the chest radiograph (Fig. 52-1).
Transient tachypnea of the newborn. An anteroposterior radiograph of a term newborn on day 1 with transient tachypnea shows bilateral linear opacities (arrow) extending from the lung hila to peripheral lung fields.