Adaptation at birth Flashcards
What is the function of the placenta
hormone production gas exchange waste removal nutrition homeostasis acid base balance transport of IgG
What is the function of the foetal liver
albumin production
Erythropoeisis - RBC
clotting factors
What is the function of the foetal kidneys
produce urine and contributes to amniotic fluid
In foetal circulation, which vessel does oxygenated blood travel through to the foetus from the mother
Umbilical vein
In foetal circulation, which vessel does deoxygenated blood return to the mother from the foetus
Umbilical arteries
In foetal circulation, what shunt exists in the liver
Ductus venosus
In foetal circulation, where can blood in the right atrium go
- through the foramen ovale into the left atrium
2. to the right ventricle and then the pulmonary arteries
In foetal circulation, what direction of blood flow do the shunts allow for
Right to left
In foetal circulation, where does blood in the pulmonary trunk go
- small volumes to the lungs
2. majority to the aorta via the ductus arteriosus
In which trimester does the baby prepare for birth
3rd trimester
What does the foetus do to prepare for labour and delivery in the 3rd trimester
surfactant production glycogen stores brown fat stores SC fat stores swallow amniotic fluid
What happens in the transition of foetal to adult circulation
Decrease in pulmonary vascular resistance
Increase in systemic vascular resistance
Increase in O2 tension
Decrease in circulating prostaglandins which closes the ductus arteriosus and venosus
Foramen ovale closes
What do the following structures normally become after delivery
Ductus arteriosus
Foramen ovale
Ductus venosus
ligamentum arteriosus
closes to form fossa ovalis
ligamentum teres
What is persistent pulmonary hypertension of the newborn PPHN
failure of the pulmonary vascular resistance to fall
and the right to left shunt persists
What investigation/examination can be done for PPHN
What is the significance
pre (right hand) and post (foot) ductal O2 saturations
>3% difference is highly suspicious of PPHN
What is the management of PPHN
Ventilation Oxygen Nitric oxide Sedation Inotropes ECLS = extra corporeal life support
What is transient tachypnoea of the newborn TTN
Diagnosis of exclusion
Common
fluid in lungs hasn’t yet cleared eg big babies delivered by c-section
How do babies thermoregulate
breakdown of brown fat
peripheral vasoconstriction - acrocyanosis
Why do babies need help keeping warm
They have a larger head than body - lose heat faster
Born wet - need drying
Babies don’t shiver
What can be used as an energy source for the brain by babies
Ketones
List causes of neonatal hypoglycaemia
Increased demands: Hypothermia, Infection
Low glycogen stores: SGA, premature
Abnormal insulin levels: maternal DM, hyperinsulinaemia
Drugs: B blockers
Which is preferred, breast milk or formula milk
Breast milk
Loss of up to __% body weight is normal for babies
10%
What chemical helps to shift HbF to HbA
2,3 BPG
Where does haematopoeisis occur in the foetus and then the neonate
Foetus: liver
Neonate: bone marrow
What types of jaundice exist
Physiological
Pathological
what happens in jaundice
breakdown of HbF + immature conjugating pathways leads to increase in unconjugated bilirubin levels
When is the onset of physiological jaundice
2 days to 2 weeks old
When is the onset of pathological jaundice
Early <24 hours/at birth
Prolonged >14 days term / >21 days pre term
What are causes of early pathological jaundice
sepsis
haemolysis from Ab mismatch
What are causes of prolonged pathological jaundice
biliary atresia!
congenital hypothyroidism
What is the management of jaundice
Phototherapy
Exchange transfusion
Why is it important to treat jaundice
to prevent Kernicterus
What is Kernicterus
accumulation of very high levels of unconjugated bilirubin which can cross the BBB and settle in the basal ganglia leading to significant neurological problems and a type of CP
what is the ideal temperature for neonates
36.5-37.5
