• Clinical science

Neonatal respiratory distress syndrome (Infant respiratory distress syndrome…)


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Neonatal respiratory distress syndrome (NRDS), or surfactant deficiency disorder, is a lung disorder in infants that is caused by a deficiency of pulmonary surfactant. It is most common in preterm infants, with the incidence and severity decreasing with gestational age. Surfactant deficiency causes the alveoli to collapse, resulting in impaired blood gas exchange. Symptoms manifest shortly after birth and include tachypnea, tachycardia, increased breathing effort, and/or cyanosis. The diagnosis is suspected based on clinical features and confirmed by evaluating the extent of atelectasis via chest x-ray. Blood gases show respiratory and metabolic acidosis, as well as hypoxia. Treatment primarily involves emergent resuscitative measures, which include nasal CPAP and stabilization of blood sugar levels and electrolytes. Additionally, intratracheal surfactant is administered if ventilation alone is not successful. Most cases resolve within 3–5 days of treatment. However, complications like hypoxemia, tension pneumothorax, bronchopulmonary dysplasia, sepsis, and neonatal death may still occur. NRDS can be prevented by administering antenatal glucocorticoids to the mother if premature delivery is expected.


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Epidemiological data refers to the US, unless otherwise specified.


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  • Impaired synthesis and secretion of surfactant
  • Risk factors that predispose to NRDS
  • Rarely, hereditary



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Clinical features

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  • History of premature birth
  • Onset of symptoms: usually presents immediately after birth
  • Signs of increased breathing effort
    • Tachypnea
    • Nasal flaring and moderate to severe subcostal/intercostal and jugular retractions
  • Typical expiratory “grunting”
  • Auscultation: decreased breath sounds
  • Cyanosis due to peripheral hypoxic vasoconstriction



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Differential diagnoses

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The differential diagnoses listed here are not exhaustive.


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  • Ventilation:
    1. Nasal CPAP with a PEEP of 3–8 cm H2O
    2. If respiratory insufficiency persists, intubation with mechanical ventilation and O2 inhalation (target O2 saturation of 90%)
  • Endotracheal administration of artificial surfactant within 2 hours postpartum
  • Supportive measures: IV fluid replacement; stabilization of blood sugar levels and electrolytes

Physiologic O2 saturation in neonates is around 90% instead of 100%. A saturation of 100% is considered toxic for the neonate!



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Bronchopulmonary dysplasia (BPD)

Further complications


We list the most important complications. The selection is not exhaustive.


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  • Neonatal RDS has a case fatality rate of 30% if not treated.
  • Most cases that have been diagnosed and promptly treated resolve within 3–5 days of treatment.


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last updated 12/13/2018
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