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Overview of Perinatal Respiratory Disorders


Arcangela Lattari Balest

, MD, University of Pittsburgh, School of Medicine

Reviewed/Revised Jul 2021 | Modified Sep 2022
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Respiratory problems in neonates include

Symptoms and signs of respiratory distress vary and include the following:

  • Grunting

  • Nasal flaring

  • Intercostal, subcostal, and suprasternal retractions

  • Weak breathing, irregular breathing, or a combination

  • Tachypnea and apneic spells

  • Cyanosis, pallor, mottling, delayed capillary refill, or a combination

  • Hypotension

In neonates, symptoms and signs may be apparent immediately on delivery or develop minutes or hours afterward.


Respiratory distress in neonates and infants has multiple causes ( see Table: Causes of Respiratory Distress in Neonates and Infants Causes of Respiratory Distress in Neonates and Infants Causes of Respiratory Distress in Neonates and Infants ).



There are several significant differences in the physiology of the respiratory system in neonates and infants compared with that of older children and adults. These differences include

  • A more compliant collapsible chest wall

  • Decreased lung compliance (in infants with surfactant deficiency due to prematurity or genetic mutations)

  • More reliance on diaphragmatic excursions over intercostal muscles

  • Collapsible extrathoracic airways

Also, infants’ smaller airway caliber gives increased airway resistance, and absence of collateral ventilation increases tendency toward atelectasis. Yet, other principles of respiration are similar in adults and children.


Evaluation of neonatal respiratory distress starts with a thorough history and physical examination.

Physical examination focuses on the heart and lungs. Chest wall asymmetry or sunken abdomen suggests diaphragmatic hernia Diaphragmatic Hernia Diaphragmatic hernia is protrusion of abdominal contents into the thorax through a defect in the diaphragm. Lung compression may cause persistent pulmonary hypertension. Diagnosis is by chest... read more Diaphragmatic Hernia . Diffuse crackles, decreased air entry, or grunting suggests poor alveolar expansion as seen in surfactant deficiency. Asymmetric breath sounds suggest pneumothorax Pneumothorax Pulmonary air-leak syndromes involve dissection of air out of the normal pulmonary airspaces. (See also Overview of Perinatal Respiratory Disorders.) Extensive physiologic changes accompany... read more or pneumonia Neonatal Pneumonia Neonatal pneumonia is lung infection in a neonate. Onset may be within hours of birth and part of a generalized sepsis syndrome or after 7 days and confined to the lungs. Signs may be limited... read more . A displaced left apical impulse, heart murmur, abnormal central or peripheral pulses, or a combination suggests a congenital heart defect Overview of Congenital Cardiovascular Anomalies Congenital heart disease is the most common congenital anomaly, occurring in almost 1% of live births ( 1). Among birth defects, congenital heart disease is the leading cause of infant mortality... read more Overview of Congenital Cardiovascular Anomalies . Assessment of blood pressure and femoral pulses may identify circulatory collapse with or without congenital defects. Poor capillary refill reflects circulatory compromise.

In both neonates and infants, it is important to assess oxygenation and response to oxygen therapy by pulse oximetry or blood gases. Chest x-ray also is recommended.

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