Adaptation of the Newborn Flashcards
What are the 3 shunts in the foetus circulation?
ductus venosus (through liver) ductus arteriosus (from pulmonary vein to aorta) foramen ovale (between the atria)
What happens to these shunts when born?
Ductus venosis = ligamentum teres
Ductus arteriosus = ligamentum arteriosum
Foramen ovale closes
What occurs during the third trimester to prepare for delivery?
surfactant production, accumulation of glycogen, brown fat stores, subcutaneous fat and swallowing of amniotic fluid
What occurs in labour?
Increase in catecholamines and cortisol
squeezing of lungs
What is the cardiac change that occurs during labour?
There is the forcing of air into the lung (when cry) and this results in the opening of pulmonary vessels and an overall lowering of pressure in the pulmonary circulation
What is PPHN? Explain
persistent pulmonary hypertension of the newborn
this occurs when there is insufficient opening of the blood vessels within the lungs so pulmonary resistance remains high
How is PPHN diagnosed?
O2 sats will be low and the baby will be pale/blue/having difficulty breathing
How is PPHN treated?
ventilation, oxygen, nitric oxide, inotropics, ECMO.
How is heat lost from a newborn?
radiation, convection, conduction, evaporation
How do newborns thermoregulate?
no shiver reflex so need to produce heat via the breakdown of brown fat stores (this is inefficient in the first 12 hrs so require help)
What are risk factors for impaired thermoregulations?
SFD or preterm
What are ways to improve thermoregulation?
hat, skin to skin, dry, blanket, heated mattress, incubator
How is glucose homeostasis maintained?
requires the mobilisation of glycogen from hepatic stores and ketones for brain metabolism
What increases glucose demand?
if hypothermia or ill
What decreases glycogen storage?
SFD or preterm
Letting down reflex or the root and suck reflex describes what process?
The baby learning to suckle and stimulate milk production
What do oxytocin and prolactin do respectively?
O = triggers milk release P = triggers milk production
What is colostrum?
This is the first milk produced by the breast and it is rich in protein and fat (very concentrated)
What is foremilk and hindmilk?
Foremilk - released at start of feed
Hindmilk - released at end of feed
What are the haematological adaptations made?
Foetal Hb becomes less efficient so adult Hb production is increased. Haematopoeisis will move to the bone marrow
What is ‘physiological anaemia’?
This is due to adult Hb made slower than the breakdown of foetal Hb (faster) resulting in anaemia
Why is there ‘physiological jaundice’?
due to the breakdown of foetal Hb. The conjugating systems in the liver are immature so there is a higher concentration of unconjugated billirubin in the blood = jaundice 2-14 days
When is jaundice considered pathological?
Early < 2 days old
Prolonged > 2 weeks old
How is jaundice treated?
Phototherapy (blue lamp)
exchange transfusion
What are some risk factors for impaired adaption?
hypoxia/asphyxiation at delivery
small for dates or preterm
sick baby
congenital abnormalities
What are some causes of PPHN?
Meconium aspiration
Infection
Congenital abnormalities
