Neonatology

Question 1

Embryo defintion

Answer 1

Fertilised ovum, until 9w

Question 2

Fetus definition

Answer 2

fertilised ovum, from 9w until delivery

Question 3

Still birth definition

Answer 3

fetal death and expulsion >24w

Question 4

Abortion definition

Answer 4

fetal death <24w

Question 5

Neonatal mortality rate

Answer 5

number of deaths of LIVE born infants within the 1st 28 days per 1000 live births

Question 6

Infant mortality rate

Answer 6

number of deaths between birth and 1 year per 1000 live births

Question 7

Perinatal mortality rate

Answer 7

number of still births and early neonatal deaths within the first 7 days per 1000 live AND still births

Question 8

Low birth weight

Answer 8

<1500g

Question 9

Presentation of CMV infection

Answer 9

CNS - periventricular calcification

Ophthal - chorioretinitis

Sensorineural deafness

Hepatosplenomegaly

Jaundice

Pneumonitis

Thrombocytopenia with petechia +/- purpura

Question 10

Rx CMV

Answer 10

oral valganciclovir or IV ganciclovir

Question 11

Ix CMV

Answer 11

PCR amplification for viral DNA
- amniotic fluid/blood/urine/CSF or saliva

Question 12

Classic triad of toxoplasmosis

Answer 12

Hydrocephalus
Chorioretinitis
Diffuse intracranial calcifications

Question 13

Ix for toxoplasmosis

Answer 13

Reference serology test
- IgM and IgG

IgM +ve indicates active infection
IgG becomes +ve after 2w and stay +ve for life

Question 14

Rx for toxoplasmosis

Answer 14

If fetal infection status not known
- Spiramycin
- Cont until term of fetal infection status documented

If fetal infection suspected or documented
- Pyrimethamine / Sulfasdiazine / Folinic acid
- Rx until 12m of age

Question 14

Presentation congenital syphilis

Answer 14

Rash
Desquamation of soles of hands & feet
Metaphyseal bone lesions

Other features same as toxoplasmosis/CMV

Question 15

Fetal varicella syndrome features

Answer 15

Limb hypoplasia
Microcephaly
Cataracts
Skin scarring (pale yellow dermatomal scars)
IUGR

Question 16

Rx fetal varicella

Answer 16

Prophylaxis
- IVIG following exposure

Rx
- IV aciclovir

Question 17

Complications of fetal varicella

Answer 17

2y bacterial infection (strep A)
Thrombocytopenia
Pneumonia
Purpura fulminans - subcut vasculitis
Cerebellitis

Question 18

Congenital parvovirus causes …?

Answer 18

red cell aplasia > hydrops fetalis

Question 19

Physioogy of PPHN

Answer 19

failure of pulmonary vascular resistance to fall within the infants first breaths, so the fetal pattern of left to right shunting across the FO and DA persists, so intrapulmonary shunting and further hypoxia occurs

Question 20

Ix for haemorrhagic disease of the newborn

Answer 20

Prolonged PT and APTT

FBC - normal platelets and fibrinogen

Clotting factors II, VII, IX and X all low

Question 21

Rx of haemorrhagic disease of the newborn

Answer 21

Vit K and FFP (need FFP becuase Vit K doesnt correct clotting times quickly enough

Question 22

Newborn hearing screening

Answer 22

1. Automated otoacoustic emissions test
2. Automated auditory brain stem response (AABR)

Question 23

When does blood spot in CF babies become unreliable

Answer 23

if done after 8w

Question 24

when to do blood spot if baby needs transfusion after birth

Answer 24

pre-transfusion and 3 days after the last transfusion

Question 25

unavoidable repeat sampling of blood spot

Answer 25

<32 weeks - need repeat day 21 Bortderline TSH results - repeat day 7-10 after 1st sample

Question 26

Gestation indicated for antenatal steroids

Answer 26

24 - 34+6 weeks

Question 27

survival rates of premature infants with active care

Answer 27

<21w - 0% 22w -10% 23w - 40% 24w - 60% 26w - 80%

Question 28

dose regime of antenatal steroids

Answer 28

betamethasone 12mg - 2 doses 2x hours apart dexamethasone 6mg - 4 doses 12 hours apart

Question 29

gestation indicated for antenatal Mg sulf

Answer 29

< 32 w

Question 30

Most common organism causing EOS

Answer 30

Group B strep - Streptococcus agalactiae

Question 31

Screening criteria for ROP

Answer 31

<31 weeks gestational age OR <1500g BW

Question 32

Timing of 1st screen for ROP

Answer 32

If born < 31 weeks - Between 31+0 and 31+6 postmenstrual age, or at 4w completed weeks postnatal age (whichever is LATER) If born >31 weeks and < 1500g - 36 weeks postmenstrual age, or 4 weeks postnatal age (whichever is SOONER)

Question 33

Pathophysiology of ROP

Answer 33

Secondary to interruption of the normal process of retinal blood vessel development following preterm birth 1. Hyperoxia has a detrimental effect on the immature retina 2. Retinal ischaemia drives vaso-proliferation

Question 34

Grading of IVH

Answer 34

I - restricted to subependymal/germinal matrix II - expansion into the lateral ventricles but <50% and remain norma size III - extension into dilated ventricles IV - grade III with parenchymal haemorrhage

Question 35

Most common affected sites in NEC

Answer 35

terminal ileum/caecum/ascending colon

Question 36

Rx PDA

Answer 36

Prostaglandin synthase inhibitor - pcm or ibuprofen Then surgical ligation if unsuccessful

Question 37

surrogate measure for bilirubin production

Answer 37

carbon monoxide

Question 38

breakdown products of haemoglobin

Answer 38

Fe Globin Carbon monoxide Biliverdin

Question 39

Interim product of haemoglobin breakdown to bilirubin

Answer 39

Biliverdin

Question 40

What is used to break down haemoglobin to biliverdin

Answer 40

haem oxygenase

Question 41

What is used to convert biliverdin to bilirubin

Answer 41

biliverdin reductase enzyme

Question 42

What does unconjugated bilirubin join with in plasma

Answer 42

albumin

Question 43

enzyme responsible for conjugating bilirubin in the liver

Answer 43

uridine disphosphate glucuronyl transferase (UGT)

Question 44

what happens to conjugated bilirubin once it has been excreted in bile from the liver

Answer 44

it is hydrolysed in the gut to form urobilinogen and stercobilinogen. also is recycled into the enterohepatic circuation (most)