Neonates

Question 1

Surfactant production physiology

Answer 1

Produced by type 2 alveolar cells (larger, less frequent) at 24weeks onwards
- Synthesis depends on pH, temp & perfusion
- Present from 20weeks but does not reach surface
- Appears in amniotic fluid 28-32 weeks
- Mature levels by 35wks

Components
- 90% lipid (80% cholesterol)- DPPC main component, apolipoproteins SpA-D
- 10% protein

Question 2

Genetic surfactant deficiency & presentation?

Answer 2

SpB = lethal
SpC = RDS at birth, fibrosis as infants
SpD- pools in airspaces, leads to emphysema

Question 3

Bell staging for NEC

Answer 3

Question 4

Neonatal abstinence syndrome, Sx, stats

Answer 4

70% will show signs of withdrawal (only half will be severe enough to need Rx)
Methadone worse than heroin
Mostly within 48h - 10d

Sx: high pitched cry, Sz, irritability, ^HR/HTN/RR, diarrhoea, vomitting, LOW, excoriation, yawning/sneezing, poor/excessive feeding, sweating

Rx NAS scoring/morphine

3% mortality

Question 5

Effects of maternal smoking on neonate?

Answer 5

• Decreased peak expiratory flow
• Increased risk LRTIs
• Increased asthma/RAD prevalence & severity
• Increased risk SIDS (prenatal > postnatal)

Question 6

Findings on amnio that suggest NTD?

Answer 6

Elevated AFP

Question 7

Findings on amnio that suggest T21?

Answer 7

Raised BHCG, PAPP-A
Low AFP

Question 8

Other conditions with raised AFP?

Answer 8

Abdominal wall defect
Annular pancreas
Duodenal atresia
EB
MF hemorrhage

Question 9

Causes of early lung maturation?

Answer 9

Steroids
Mat HTN/renal vascular disease
PROM
Mat narcotic addiction
+/- placental insufficiency/PTL

Question 10

Causes of delayed lung maturation?

Answer 10

GDM (without vascular disease)
Hydrops

Question 11

Complications with NSAIDs for PDA closure

Answer 11

Risk of complications: low platelets, AKI, NEC, GI bleed/perforation, alterations in cerebral blood flow.
* Ibuprofen = less AKI / NEC than indomethacin, similar efficacy, no differences in long term outcome or IVH.
* Indomethacin  reduced IVH and pulmonary haemorrhage= no difference in death, long term disability, CLD.

Risks of PDA open:
Death, CLD, NEC, IVH, CP, PVL

Question 12

Time period of decline in PVR after birth

Answer 12

Rapidly in 2-3 days
Reaches adult levels at 2 weeks

Question 13

Congenital central hypoventilation syndrome (CCHS)- genetics, symptoms

Answer 13

AD- variable penetrance
PHOX2B 90%
MY01H and LBX1 - if consanguinous
1/150,000

Global autonomic dysfunction.
* Abnormally reduced ventilatory response to hypoxia and
hypercapnia.
* Cardiac, Ocular and Endocrinological symptoms.
* Associated with Hirschsprung Disease (Haddad syndrome)
*Neural crest tumours- neuroblastoma, ganglioneuroma + phaeo, medullary thyroid Ca

Question 14

What is IFALD? How is it prevented

Answer 14

IFALD = liver disease associated with
intestinal failure with multifactorial cause.

• Potentially life-threatening
• Historically 10-50% of children receiving
  prolonged PN have died from IFALD.
• Soy based = most risk