Respiratory Disorders in the Newborn: Identification and Diagnosis

Hany Aly, MD, FAAP* 1. *Assistant Professor of Pediatrics and of Obstetrics & Gynecology; Director, Newborn Services, George Washington University, Washington, DC After reading this article, readers should be able to: 1. Describe the specific radiologic findings in neonatal respiratory distress syndrome. 2. Differentiate between the normal results of a newborn chest radiograph and the radiographic patterns that reflect meconium aspiration. 3. Differentiate between the normal results of a newborn chest radiograph and the radiographic patterns that reflect pneumonia. 4. Distinguish between pulmonary disease and cyanotic congenital heart disease as a cause of hypoxemia and acidosis in a neonate. Respiratory distress is encountered frequently in newborns and represents the most frequent indication for re-evaluation of the young infant. Because respiratory distress in the newborn may be a potentially life-threatening condition, physicians are expected to assess and manage affected infants promptly. The key to successful management of the infant who has respiratory distress is based on the ability to obtain a complete maternal and newborn history, perform a thorough physical examination, recognize the common respiratory disorders, differentiate among various diagnostic entities, and identify those that are life-threatening. Respiratory distress in the newborn is characterized by one or more of the following: nasal flaring, chest retractions, tachypnea, and grunting. Nasal flaring is a relatively frequent finding in an infant attempting to decrease airway resistance. Suprasternal retraction indicates upper airway obstruction. Subcostal retraction, on the other hand, is a less specific sign that may be associated with either pulmonary or cardiac diseases. Normally, the neonate takes 30 to 60 breaths/min. The infant breathes at a faster rate to maintain ventilation in the face of decreased tidal volume. An infant in respiratory distress may try to maintain lung volume with adequate gas exchange by partially closing the glottis during expiration. This is the mechanism responsible for the audible grunting in these infants. An infant who has an advanced degree of respiratory distress may exhibit additional signs, such as cyanosis, gasping, …