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Overview of Perinatal Respiratory Disorders


Arcangela Lattari Balest

, MD, University of Pittsburgh, School of Medicine

Reviewed/Revised Jul 2023
Topic Resources

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.

Etiology of Perinatal Respiratory Disorders

Respiratory distress in neonates and infants has multiple potential causes (see table ).


Physiology of Perinatal Respiratory Disorders

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 Perinatal Respiratory Disorders

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 occurs in surfactant deficiency. Asymmetric breath sounds suggest pneumothorax 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 shunting (eg, bounding pulses in arteriovenous malformations or patent ductus arteriosus Patent Ductus Arteriosus (PDA) Patent ductus arteriosus (PDA) is a persistence of the fetal connection (ductus arteriosus) between the aorta and pulmonary artery after birth. In the absence of other structural heart abnormalities... read more Patent Ductus Arteriosus (PDA) ) or left heart dysfunction, 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.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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