Prematurity

Question 1

When is a child described as being premature?

Answer 1

Delivered at <37 weeks gestation

Question 2

When is a child described as being of low birth weight (LBW)?

Answer 2

<2500g

Question 3

When is a child described as being moderately premature?

Answer 3

Delivered at 35-37 weeks

Question 4

When is a child described as being very premature?

Answer 4

Delivered at 29-34 weeks

Question 5

When is a child described as being extremely premature?

Answer 5

Delivered at = 28 weeks

Question 6

What are the RFs for prematurity?

Answer 6

1. Previous prematurity
2. Multiple gestation
3. Cervical incompetence
4. PROM
5. Maternal infection
6. Maternal chronic disease
7. Maternal substance use, e.g. smoking

Question 7

What are the 3 possible neurological consequences of prematurity?

Answer 7

1. Intraventricular haemorrhage (IVH)
2. Periventricular leukomalacia (PVL)
3. Hypoxic ischaemic encephalopathy (HIE)

Question 8

What is HIE?

Answer 8

Swelling and irritation of the brain caused by lack of oxygen

Question 9

When may HIE occur?

Answer 9

1. Failure of gas exchange across the placenta
2. Interruption of the umbilical blood flow
3. Inadequate maternal placental perfusion
4. Compromised foetus
5. Failure of cardiorespiratory adaptation at birth

Question 10

What is the most common cause of neonatal seizures?

Answer 10

HIE

Question 11

If a seizure is going to occur with HIE, when do they generally do so?

Answer 11

Within 24 hours of delivery

Question 12

What neurological condition is associated with PVL?

Answer 12

CP

Question 13

What cell produces surfactant?

Answer 13

Type II alveolar cells

Question 14

At what point do these cells begin producing surfactant?

Answer 14

26 weeks at the earliest, so any baby born before this will certainly have inadequate surfactant

Question 15

When is a child defined as having tachypnoea?

Answer 15

> 60

Question 16

What is an infant trying to achieve by grunting?

Answer 16

Grunting attempts to create a positive airway pressure to maintain functional residual capacity

Question 17

What is the characteristic appearance of RDS on XR?

Answer 17

Ground-glass

Question 18

What drug may be given to reduce the risk of RDS if a premature delivery is imminent?

Answer 18

Maternal corticosteroids

Question 19

What may be given to the infant post-delivery should they be suffering with RDS?

Answer 19

Synthetic surfactant therapy

Question 20

When does the ductus arteriosus close in a full-term/normal BW infant?

Answer 20

Within 3 days of delivery

Question 21

What happens if the DA DOESN’T close 3 days post-delivery?

Answer 21

Oxygenated blood of the aorta mixes with deoxygenated blood of the pulmonary artery. Results in tachycardia, SOB, difficulty feeding and a ‘machine-like’ heart murmur

Question 22

Whom is at risk of non-DA closure?

Answer 22

LBW infants, i.e. often premature infants

Question 23

What can be given to close the DA?

Answer 23

NSAIDs

Question 24

How does NSAIDs close the DA?

Answer 24

They decrease prostaglandin synthesis, it being prostaglandin E1 that is responsible for the DA’s patency. Without prostaglandins the DA can not remain open

Question 25

What is the most common neonatal surgical emergency?

Answer 25

Necrotising enterocolitis (NEC)

Question 26

What part of the bowel is most commonly effect by NEC?

Answer 26

Terminal ileum + proximal colon

Question 27

What may be protective against NEC?

Answer 27

Breast milk + antenatal steroids

Question 28

What are the characteristic XR signs in NEC?

Answer 28

1. Intramural air
2. Distended bowel loops
3. Air in portal tract
4. (Air under diaphragm when bowel has perforated)

Question 29

What oxygen sats are aimed for in a pre-term infant and why?

Answer 29

92-94% - because oxygen toxicity poses risk of retinopathy of prematurity (ROP)

Question 30

What infants are screened for ROP?

Answer 30

Those born at:

1. <32 weeks gestation
2. <1500g BW