Respiratory distress in the newborn

Abstract

Respiratory distress presents as tachypnea, nasal flaring, retractions, and grunting and may progress to respiratory failure if not readily recognized and managed. Causes of respiratory distress vary and may not lie within the lung. A thorough history, physical examination, and radiographic and laboratory findings will aid in the differential diagnosis. Common causes include transient tachypnea of the newborn, neonatal pneumonia, respiratory distress syndrome (RDS), and meconium aspiration syndrome (MAS). Strong evidence reveals an inverse relationship between gestational age and respiratory morbidity. (1)(2)(9)(25)(26) Expert opinion recommends careful consideration about elective delivery without labor at less than 39 weeks’ gestation. Extensive evidence, including randomized control trials, cohort studies, and expert opinion, supports maternal group B streptococcus screening, intrapartum antibiotic prophylaxis, and appropriate followup of high-risk newborns according to guidelines established by the Centers for Disease Control and Prevention. (4)(29)(31)(32)(34) Following these best-practice strategies is effective in preventing neonatal pneumonia and its complications. (31)(32)(34). On the basis of strong evidence, including randomized control trials and Cochrane Reviews, administration of antenatal corticosteroids (5) and postnatal surfactant (6) decrease respiratory morbidity associated with RDS. Trends in perinatal management strategies to prevent MAS have changed. There is strong evidence that amnioinfusion, (49) oropharyngeal and nasopharyngeal suctioning at the perineum, (45) or intubation and endotracheal suctioning of vigorous infants (46)(47) do not decrease MAS or its complications. Some research and expert opinion supports endotracheal suctioning of nonvigorous meconium-stained infants (8) and induction of labor at 41 weeks’ gestation (7) to prevent MAS.

Figure 1.

Case 1: Transient tachypnea of the newborn is characterized by streaky, pulmonary interstitial markings and fluid in the fissure apparent on chest radiograph. Case 2: Neonatal pneumonia with bilateral opacities, air bronchograms, and pleural effusions is apparent. Case 3: Respiratory distress syndrome is characterized by diffuse, bilateral, ground glass fields with air bronchograms secondary to diffuse atelectasis. Case 4: Meconium aspiration syndrome causes a chemical pneumonitis, partial airway obstruction, and a localized surfactant inactivation that leads to areas of hyperinflation mixed with diffuse, patchy infiltrates radiographically.

Figure 2.

Common complications of meconium aspiration syndrome include pneumothorax (left upper) and persistent pulmonary hypertension of the newborn (right upper) characterized by cyanosis with normal lung fields and decreased pulmonary vascular markings.