Diagnostics

previous preterm birth

• Interstitial pulmonary edema with perihilar streaking

• Diffuse, fine, reticulogranular (ground-glass) densities with low lung volumes and air bronchograms

• Atelectasis

• Hypoxia with respiratory acidosis; may lead to increased lactate levels

• Evaluate for partial respiratory failure or global respiratory failure

—> screening for markers of fetal lung immaturity

• Lecithin-sphingomyelin ratio < 1.5 (≥ 2 is considered mature)

  • The amount of sphingomyelin in the amniotic fluid remains relatively consistent during pregnancy.

  • The amount of lecithin, which is the major component of surfactant, starts increasing after week 26 of gestation.

  • The lower the lecithin-sphingomyelin ratio, the more likely it is that the lungs are immature.

• Foam stability index < 0.48

  • A semi-quantitative test used to assess fetal lung maturity

  • Amniotic fluid is mixed with ethanol until foam formation ceases to occur

  • The index refers to the highest quantity of ethanol that can be added to amniotic fluid still permitting the formation of foam.

• Low surfactant-albumin ratio

• Hyaline membranes lining the alveoli

  • Composed of fibrin, cellular debris, and red blood cells

  • Eosinophilic appearance, amorphous material lining the alveolar surface

• Engorged and congested capillary vessels in the interstitium