fetal / neonatal Flashcards
Complications in the fetus from indomethacin in pregnancy include:
a. renal insufficiency
b. oligohydramnios
c. premature closure of the ductus arteriosus
d. all of the above
e. none of the above
d. all of the above
Its an NSAID
Cardiovascular changes at birth
A - the brain is the organ that receives the most dramatic increase in blood flow
B - pulmonary vascular resistance and pulmonary blood flow decrease
C - foramen ovale is a flap valve that becomes functionally closed when L atrial pressure exceeds R atrial pressure
D - prostaglandins have a minor role in physiological closure of ductus arteriosus
C - foramen ovale is a flap valve that becomes functionally closed when L atrial pressure exceeds R atrial pressure
Occurs in the first few minutes of life
DUCTUS ARTERIOSUS - closes over course of a few hours
Pulmonary artery goes from high pressure to low pressure
Fall in prostaglandin (from placenta being removed) –> closure of ductus arteriosus
Also get constriction of smooth muscle in ductus arteriosus from high oxygen levels
What is the blood volume of a newborn baby weighing 3500gm?
A. 150 ml B. 250 ml C. 300 ml D. 350 ml E. 400 ml
D. 350 ml
Another set on answers say 300ml
BV of a child is around 85-105 ml/kg (WHO)
An ultrasound examination reveals that your patient has a fetus with gastroschisis. You advise her that:
A - The fetus has >30% chance of an associated chromosomal abnormality
B - Surgical repair is successful in <20% of cases
C - It is uncertain whether LUSCS confers any advantages over NVD
D - The infant is likely to have severe mental retardation
C - It is uncertain whether LUSCS confers any advantages over NVD
Surgical repair is often successful Neonatal mortality low (5-10%) Increased risk of FGR and PTB Neonatal bowel complications The opening is near the umbilicus but towards to right and not directly over it - no increase in incidence of chromosomal abnormalities - only contains small bowel usually - a/w oligo
Omphalocele - membrane covered herniation, inserts into the apex of the sac (of cord insertion)
- high incidence with associated abnormalities / genetic syndromes / chromosomal abnormalities (T13, 18)
- Can contain stomach, liver, spleen
- a/w poly
What is the fetal PaO2 at term?
A - 22 mmHg B - 32 mmHg C - 42 mmHg D - 52 mmHg E - 62 mmHg
B - 32 mmHg
32-35mmHg in the fetal umbilical vein
Compared to 90-100mmHg in mum
What is the cord pH at term immediately after a normal labour and delivery?
A - Vein 7.3, artery 7.27
B - Vein 7.27, artery 7.3
c - Vein 7.5, artery 7.2
d - Vein 7.2, artery 7.5
A - Vein 7.3, artery 7.27
Median artery pH - 7.27
Median vein pH - 7.35
Which of these crosses the placenta the least?
A - TSH
B - T4
C - TRH
D - Propylthiouracil
A - TSH
Don’t cross
- TSH
Does cross
- TRH
Which of the following drugs will affect the fetus adversely if used during pregnancy?
A - Flagyl
B - Heparin
C - Thiazide diuretics
D - Azothiaprine
C - Thiazide diuretics
Increase risk of malformations, fetal/neonatal electrolyte abnormalities, jaundice and thrombocytopenia
The most common cause of term infant mortality is:
A - congenital abnormalities B - infection C - NEC D - Bronchopulmonary dysplasia E - IVH
B - infection
You see a patient with bipolar disease on Lithium 900mg /day. The risks to the fetus include:
A - CNS abnormalities
B - Cardiac abnormalities
C - Renal anomalies
D- Postmaturity
B - Cardiac abnormalities
Ebstein’s anomaly - septal and posterior leaflets of tricuspid valve are displaced towards the apex of the right ventricle –> tricuspid regurgitation –> RA dilatation
Foramen ovale doesn’t close sometimes
Rx: valve replacement and closure of the foramen ovale
Phenytoin is associated with all of the following except:
A - IUGR B - Mental retardation C - Spina bifida D - Cardiac anomalies D - Cleft palate
C - Spina bifida
"Fetal dilantin syndrome" Growth deficiency Developmental delay Characteristic facies GU abnormalities Cleft palate
Neonatal thyroid function which are true:
a - increase in thyroxine after birth in preterm but not term infants
b - neonatal rise in T4 due to TSH increase
c - thyroxine is involved in shivering but not non-shivering thermogenesis
b - neonatal rise in T4 due to TSH increase
Serum TSH concentrations rise abruptly A/w exposure to cold Initial surge in TSH --> stimulates T4 secretion T4 peaks 24-36h of life Serum T3 also rises at same time
serum TSH levels rise rapidly in the first minutes after birth and peak at 30 minutes of postnatal life
A woman with bipolar affective disorder on lithium presents at 11/40. Serum lithium is 1.0 (0.9-1.4). She should be told:
a - lithium is suspected of causing heart defect
b - to cease lithium now will reduce risk to the baby
c - to reduce dose will reduce risk to baby
d - she should have CVS
e - should have amniocentesis at 16/40
a - lithium is suspected of causing heart defect
Which drug should not be used in lactation
a - Amiodarone
b - Warfarin
c - Digoxin
d - Propylthiouracil
a - Amiodarone
Secreted in high amounts in breastmilk
Contraindicated in breastfeeding
Rare cases of hypothyroidism in baby
PTU - safe 1st trimester, later in pregnancy risk of maternal liver disease, safe in breastfeeding
Warfarin - avoid in 1st trimester, 2nd and 3rd can give, safe in breastfeeding
Digoxin - minimal amounts in breastmilk, in pregnancy crosses placenta but not known to be harmful - lacking data
Which of the following is the most common cause of neonatal hyperthyroidism?
a - previous thyroidectomy on thyroxine b - Graves disease treated with PTU c - Maternal exposure to Iodine 131 during pregnancy d - Iodine deficiency goitre e - Maternal Hashimoto’s thyroiditis
b - Graves disease treated with PTU
TSH receptor stimulating antibodies (TSI)
PTU doesn’t reduce TSI
TSI can cross the placenta
Most likely cause of perinatal mortality with diabetes?
a - fetal hypoglycaemia b - congenital abnormality c - APH d - Fetal hyperinsulinaemia e - PIH
d - Fetal hyperinsulinaemia
PEDERSON HYPOTHESIS
Maternal high glucose –> fetal hyperinsulinaemia –> high rates of fetal growth and subcut fat and glycogen deposition in liver –> increased fetal metabolic rate which can provoke fetal hypoxia
Congenital abnormality - 2-4 fold increased risk
- T1DM 2.9-7.5%
- T2DM 2.1-12.3%
Management in suspected fetal hypothyroidism?
a - give mother thyroxine
b - intraamniotic thyroxine
c - do nothing in utero but give thyroxine to neonate
d - none of the above
c - do nothing in utero but give thyroxine to neonate
Usually due to TSH receptor blocking antibodies crossing the placenta
- More common in women with atrophic thyroiditis rather than Hashimoto’s
2% of congenital hypothyroidism
Refer MFM for serial USS
To pick up most no. of causes of neonatal hypothyroidism
a - TSH only
b - TSH first and if elevated do T4
c - Both TSH and T4
d - T3
b - TSH first and if elevated do T4
TSH on guthrie card
Screening for congenital hypothyroidism
Primip with no antenatal care delivers 1000 gm baby at 28/40. What is most likely cause of death?
A - sepsis
B - temp instability
C - intracranial haemorrhage
D - RDS
D - RDS
as per Lancet article
What features are suggestive of neonatal hypothyroidism – except?
a - hypotonia
b - atypical facies
c - open posterior fontanelle
d - slow heart rate in labour
b - atypical facies
swollen eyes, but no other atypical facies
Which one crosses the placenta
a - heparin only
b - warfarin only
c - heparin and warfarin
d - none of the above
B - warfarin only
Which one causes stipling of the epiphysis?
a - heparin only
b - warfarin only
c - heparin and warfarin
d - none of the above
b - warfarin only
stipling = pattern of focal bone calcification
- caused by warfarin, hypothyroidism, alcohol
What is the risk of congenital heart block with anti Ro + La antibodies?
A - 5%
B - 10%
C - 20%
A - 5%
most likely to be assoc with oligohydramnios:
A - VSD- isolated
B - posterior urethral valves
C - PUJO – unilateral
D - duodenal atresia
B - posterior urethral valves
Keyhole sign on USS - distended bladder, oligo
PUJO = pelvic ureteric junction obstruction
most likely to be assoc with abnormal karyotype
A - VSD- isolated
B - posterior urethral valves
C - PUJO – unilateral
D - duodenal atresia
D - duodenal atresia
30% of duodenal atresia with have T21
3% of those with T21 will have duodenal atresia
Vactryl association
Which of the following cannot be detected on routine US scanning?
a - hydrocephalus
b - exomphalos
c - cystic fibrosis
d - cleft palate
c - cystic fibrosis
A previously healthy 4 day old infant becomes hypotensive and dehydrated, low Na and high K. Which definitive Ix likely to be positive next?
raised 17-OH progesterone (>200)
CAH
- salt-wasting crisis
Predominant Hb type in neonate?
a - HbA
b - HbA2
c - HbF
d - HbH
c - HbF