1: Neonatology - IUGR

Question 1

Define IUGR

Answer 1

Failure of growth in-utero that may or may-not cause SGA

Question 2

Define SGA

Answer 2

Weight below 10th-centile for gestational age

Question 3

What are the two types of IUGR

Answer 3

1, Symmetrical

2. Asymmetrical

Question 4

What causes asymmetrical IUGR

Answer 4

• Due to external factors, most commonly placental insufficiency. Occurs late in gestation.

Question 5

What causes symmetrical IUGR

Answer 5

• Due to internal factors (Chromosomal abnormalities)

Question 6

What are two maternal causes of IUGR

Answer 6

• Substance abuse

- Teratogenic medications

Question 7

What is the main utter-placental cause of IUGR

Answer 7

Placental insufficiency

Question 8

What is placental insufficiency

Answer 8

Disruption in maternal-foetal circulation impairing substances exchange causing foetal compromise

Question 9

What are 5 causes of placental insufficiency

Answer 9

• DM
• HTN
• Smoking
• Antiphospholipid syndrome
• SLE
• Pre-eclampsia
• Rhesus incompatibility

Question 10

What are 3 foetal causes of IUGR

Answer 10

Chromosomal abnormality
TORCH
Cyanotic heat defects

Question 11

What is 70% of IUGR

Answer 11

Asymmetrical

Question 12

How will symmetrical growth IUGR present

Answer 12

Proportional decrease in head and abdominal circumference

Question 13

When does symmetrical IUGR usually occur

Answer 13

Abnormalities in brain development

Question 14

What is a more common complication of symmetrical IUGR and why

Answer 14

Abnormalities in brain development - due to occurring in first trimester

Question 15

How does asymmetrical IUGR present

Answer 15

Maintained head circumference, small abdominal circumference

Question 16

Explain pathophysiology of asymmetrical IUGR

Answer 16

Placental dysfunction decreases nutrients and oxygen delivered. Foetus therefore preferentially shunts oxygen and nutrients to vital organs, including the brain. Foetus then switches to glycolysis, which causes metabolic acidosis and foetal multi-organ failure

Question 17

What are features of IUGR on growth restriction

Answer 17

Below 10th gentile

May have oligohydramnios

Question 18

In asymmetrical IUGR, what will be seen on doppler US

Answer 18

Reduced umbilical blood flow

Question 19

What is a risk with IUGR

Answer 19

Baby born low birth weight - which increases risk of sudden infant death syndrome

Question 20

What is small for gestational-age

Answer 20

Weight below 10th centile of that for gestational age

Question 21

What is symmetrical SGA

Answer 21

All growth parameters are symmetrically small

Question 22

What causes symmetrical SGA

Answer 22

Chromosomal aberrations

Constitutionally small

Question 23

What is asymmetrical SGA

Answer 23

Weight is proportional smaller compared to head circumference and length

Question 24

What is the main cause of asymmetrical SGA

Answer 24

Pre-eclampsia

Question 25

What does SGA increase risk of

Answer 25

``` Perinatal asphyxia Hypoglycaemia Necrotising enterocolitis Meconium aspiration Polycythaemia TORCH infections ```

Question 26

Why does SGA increase risk of hypoglycaemia

Answer 26

Less glycogen stores

Question 27

Why does SGA increase risk of polycythaemia

Answer 27

Chronic in-utero hypoxia

Question 28

What is LGA

Answer 28

Babies weight >90th centile that for gestational age

Question 29

What are 4 causes of LGA

Answer 29

Constitutional Maternal DM Beckwith-weidemann syndrome Hydrops foetalis

Question 30

What is the presentation of beckwith-widemann syndrome

Answer 30

Hypoglycaemia Crease near ears Organomegaly Macroglossia

Question 31

What are the risks of LGA

Answer 31

Syndrome of over-growth that presents with - Perinatal asphyxia - Shoulder dystocia - Clavicle fracture - Nerve palsies - Hypoglycaemia