Respiratory Distress in the Term and Near-term Infant

Abstract

After completing this article, readers should be able to: 1. Differentiate between cardiac and respiratory causes of cyanosis. 2. Describe the primary parenchymal diseases that can cause respiratory distress in the neonate. 3. Describe the primary developmental lung abnormalities that can cause respiratory distress in the neonate. One of the most common reasons for admission of term neonates to a neonatal intensive care unit (NICU) is respiratory distress. (1) The cause may be of pulmonary or nonpulmonary origin. The nonpulmonary causes include cardiac, infectious, metabolic, central nervous system, and miscellaneous conditions. This review focuses on the major pulmonary causes for respiratory distress in term infants, in particular, the first two of the four groups that appear in Table 1. (2) | Parenchymal conditions | || | Developmental abnormalities | | Airway abnormalities | | Mechanical abnormalities | Table 1. Potential Pulmonary Causes for Respiratory Distress in Neonates Differentiating cardiac and respiratory causes of cyanosis is a common clinical problem, particularly in cases in which there is little or no tachypnea or respiratory distress. The major signs of neonatal respiratory distress are tachypnea and cyanosis, in which tachypnea is defined as a respiratory rate consistently greater than 60 breaths/min. A hyperoxia test may assist in differentiating between the two. Pulse oximetry may help to decide whether a formal hyperoxic test is useful. A neonate who exhibits cyanosis without marked respiratory distress and has an O2 saturation of less than 85% in both room air and 100% oxygen likely has an intracardiac shunt. If the O2 saturation increases to more than 85% on 100% oxygen, …