Respiratory Distress in the Newborn

Question 1

What is the definition of respiratory distress in neonates?

Answer 1

• tachypnoea >60/min
• increased WOB = subcostal, intercostal, tracheal tug, nasal flaring, head bobbing
• noisy breathing = stridor, wheeze, grunting (end expiratory pressure, end expiratory volume in lungs)
• central cyanosis.

Question 2

What are some causes of RD in neonates?

Answer 2

Transient

• post-asphyxia (hypoxia in utero, fix it because metabolic acidosis)
• hypo/hyperthermia (increase metabolic rate)

Term:

• sepsis/pneumonia/meningitis = most dangerous
• wet lung = most common (transient tachypnoea of newborn)
  
  • 1-2% cold C sections - gradually improves
  • investigations
    
    • slightly hazy XR, fluid in fizzure

Other:

• meconium aspiration syndrome
  
  • mechanism
    
    • blocks airway (complete - distal collapse, incomplete - inflammation and air leaks)
    • chemical pneumonitis = bile salts
    • +/- infection
  • Ix - consolidation
  • Tx - prevention - rapid delivery, avoid post-term birth
  • impossible in preterm babies, and those who cannot pass meconium
• congenital
  
  • cardiac - antenatally diagnsed (ebstein’s anomaly, TOF, TGA with intact ventricular septum, HLHS with PFO).
  • space occupying lesion (diaphragmatic hernia)
• pneumothroac - decompress with chest drain.

Question 3

What are some risk factors for sepsis?

Answer 3

• respiratory distress
• GBS + swab
  
  • Causes: (birth canal)
    
    • GBS,
    • GNB - protected in cold CS theoretically.
• chorioamnionitis
  
  • maternal/foetal fever/hypothermia
• prolonged rupture of membranes (18-24hrs)
• mechonium stained liquor
• spontaneous labour <35weeks - IV antis
• blood markers for infection
  
  • WCC
  • NP
  • I/T ratio bands
  • CRP

Question 4

What is the treatment for neonatal sepsis?

Answer 4

• IV benpen + gentamicin (no broad spectrum antibotics - microbiota, GBS never develop resistance benzpen).
• give AFTER blood culture
• GBS prevention
  
  • screening at 35-7weeks
  • prophylaxis 4hrly in labour
    
    • subsequent pregnancies.

Question 5

What is hyaline membrane disease? How do you know? Treatment?

Answer 5

• lack of surfactant because its switched on by cortisol at 34weeks
  
  • smaller airway more likely to collapse.
  • surfactant deficiency - atelectasis - hypoxia - alveolar type 2 cell metabolism decreased.
• natural history - gets worse before it gets better.
• excessive fluid - can be primary or secondary (MAS/infection)

Investigations:

• CXR - under-inflated lungs, ground-glass reticulonodular pattern.
• RFs:
  
  • prematurity
  • asphyxia
  • maternal diabetes
  • second twin, male, FHx.
  • CS
• Treatment:
  
  • antenatal corticosteroids <35weeks
  • IM given 2 doses back to back 24hrs apart
  • delivery room:
    
    • O2 - 91-95% -pulse oximeter
      
      • if too high get retinopathy of prematurity
      • CPAP
  • antibiotics if unsure
  • acid-base
  • haemoglobin
  • surfactant:
    
    • reduces death
    • natural are better than synthetic (derived from animal proteins)
      
      • used to have to intubate to give it
      • now give it into trachea (off mechanical ventilator)
      • mist