RESPIRATORY DISTRESS SYNDROME

Question 1

What is respiratory distress syndrome mainly caused by? It is largely seen in which patient group?

Answer 1

Surfactant deficiency

Largely in preterm infants: rare if over 32 weeks gestation

Question 2

What is the function of surfactant in the lungs? Which three hormones increase production and what decreases production?

Answer 2

Reduces surface tension in alveoli, preventing alveoli from collapsing

• Stimulated by cortisol, thyroxine, prolactin,
• Inhibited by insulin (Think: diabetic mother)

Question 3

What type of delivery is associated with increased risk of respiratory distress syndrome?

Answer 3

Cesarian section

Question 4

List a key symptom that if it occurs within four hours of birth should raise a red flag for respiratory distress syndrome

Answer 4

Grunting

Question 5

What investigations should you consider in a baby who you think has respiratory distress syndrome (cyanosis, tachypnoea, grunting)? What do you expect to see?

Answer 5

• SpO₂ monitoring and blood gases
• CXR: bilateral, diffuse groundglass appearance (generalised atelectasis), air bronchogram

Question 6

What is shown in this x-ray?

Answer 6

Air bronchogram: air-filled bronchi (dark) being made visible by opacification of surrounding alveoli. Almost always caused by pathologic airspace/alveolar process, in which something other than air fills alveoli

Question 7

Outline the treatment of respiratory distress syndrome

Answer 7

• Intubation and administration of surfactant (extremely pre-term) or nasal CPAP
• Antibiotics: penicillin and gentamicin until congenital pneumonia excluded
• Nutrition: IV fluids until stable then gastric tube feeds + slow increase as tolerated. If unstable start parenteral nutrition after 24 to 48 hours
• Closely monitor oxygen requirements

Question 8

Which infection can both mimic and coexist with RDS? How do you treat this?

Answer 8

Congenital pneumonia: penicillin and gentamicin

Question 9

What is the prognosis of RDS? What can around 15% of cases go on to develop?

Answer 9

Majority have a good recovery

• Mortality is 5 to 10% and depends on severity and gestation
• Bronchopulmonary dysplasia may develop in 15% of cases and is inversely proportional to gestational age

Question 10

How can you prevent respiratory distress syndrome prenatally?

Answer 10

• Corticosteroids: given to mother 1 to 7 days before birth. Decreases incidence and mortality by 40%
• Treat coexisting morbidity is that inhibits surfactant production e.g. hypothermia, acidosis, infection