• Clinical science

Neonatal respiratory distress syndrome (Infant respiratory distress syndrome…)


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 suspected diagnosis is based on clinical features and confirmed by evaluating the extent of atelectasis via chest x-ray. Blood gases show respiratory and metabolic acidosis in addition to hypoxia. Treatment primarily involves emergent resuscitative measures, including nasal continuous positive airway pressure (CPAP) and stabilizing blood sugar levels and electrolytes. In addition, intratracheal surfactant is administered if ventilation alone is unsuccessful. Most cases resolve within 3–5 days of treatment. However, complications such as 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.



Epidemiological data refers to the US, unless otherwise specified.





Clinical features

  • History of premature birth
  • Onset of symptoms: usually immediately after birth but can occur within 48–72 hours postpartum
  • 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




Differential diagnoses

Neonatal respiratory distress syndrome

Transient tachypnea of the newborn (wet lung disease) [10] Persistent pulmonary hypertension of the newborn (PPHN) [11] Meconium aspiration syndrome [12][13][14]
  • Usually postterm
  • Delayed resorption of fetal lung fluid
Risk factors
  • Perinatal asphyxia
  • Prolonged premature rupture of the membranes
  • Infection
Onset of symptoms
  • Within the first minutes/hours after birth
  • Immediately after birth and within the next 2 hours
  • Within 24 hours after birth
  • Immediately after birth
Clinical features
  • Tachypnea
  • Increased breathing effort
  • Diffuse crackles, diminished, or normal breathing sounds on auscultation
  • Symptoms are reversible
  • Low APGAR scores
  • Cyanosis and signs of respiratory distress
  • Heart examination: prominent precordial impulse and a narrowly split and accentuated S2
  • Supportive care
  • Administration of artificial surfactant
  • Supportive care (e.g., supplemental oxygen, neutral thermal environment, adequate nutrition)

The differential diagnoses listed here are not exhaustive.


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



Bronchopulmonary dysplasia (BPD)

Further complications

Baby oxen have RIBs: Babys receiving too much oxygen get Retinopathy of prematurity, Intraventricular hemorrhage, and Bronchopulmonary dysplasia.


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


  • If left untreated, NRDS has a case fatality rate of 30%.
  • Most cases that are promptly treated resolve within 3–5 days.



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last updated 08/27/2020
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