lecture 4 foetal and neonatal development Flashcards
what happens to the urine produced by the kidneys
swallow
what prevents an asceding infections
plug
what is the foetus totally reliant on
placenta
example of a disease caused by lack of good placenta
IUGR - Intrauterine growth restriction
what is passed through the placenta important for immune defence
antibodies
can infection be passed across the placenta
yes
newborns should be
warm
sweet
pink
why are babies airways easily obstructed
small
difference in vocal cords of a preterm
bulbous instead of which strands
at first how does the lung form
buds off the embryonic forgut
why may a preterm not be able to breathe because of the lungs
underdeveloped - no terminal bud - no surface for gas exchange
what is it when gut ends up in the chest
diaphragmatic hernia
what is surfactant made by
type two pneumocytes in the alveoli
when is surfactant made
last two week of gestation
what is surfactant
phospholipid
why do we have surfactant
reduce surface tension in the lungs
what is respiratory distress syndrome caused by
babies being born pre term and so they have no surfactant
main reason you might be deficient in surfactant
prematurity
other reasons you have low surfactant
infection
acidosis
hypothermia
meconium aspiration
what is meconium aspiration
eating foetal poop
what can babies born premature be given to overcome low surfactant
steroids
what is a case where nothing can be done about no surfactant
congenital lack of type 2 pneumocytes
what colour is a premature baby’s skin
red
why is a preterm baby’s skin red
lack of dermis
other features of pre term babies
disproportionately big head
no subcutaneous fat
what is the sightings on a radiograph called with a baby with RDS
ground glass effect
what might happen if you put two much pressure in a babys lung
pneumothorax
what is the placenta made of
trophoblast tissue
what is the blood supply from for the placenta on the maternal
spiral arteries
does mum and baby blood mix
no i think youll find it dosent
what supplies foetus from placenta
umbilical vein
what returns blood to the placenta
umbilical arteries
what kind of blood do the umbilical arteries contain
deoxygenated
what kind of blood do the umbilical veins contain
oxygenated
what duct allows the passage from umbilical vein to IVC
ductus venosus
what does foetal circulation bypass
liver
lungs
what allows the blood to go from right to left atria
foramen ovale
or ductus arteriosus
what does the ductus arteriosus become in the adult
ligamentum arteriosus
how is foetal circulation sustained in this way
high pressure in lungs
low pressure rest of body
how is the liver bypassed
ductus venosus
how does the foetal circulation chnage once born
breathe = low pressure in the lungs = circulation has to adapt
what happens to the ductus arteriosus after birth
constricts
why does the ductus arteriosus constrict
hormonal change - prosoglandin
transpositioning of the great arteries
two circularatory systems that dont cross
can babies in utero survive with transpositioning of the great arteries
yaaaas betch
how would you treat transpositioning of the great arteries
surgery
inefficient left side of the heart?
Hypoplastic left heart syndrome
what is persistent pulmonary hypertension in a new born
lungs not working
blood bypasses lungs still
what does the blood bypass the lungs with
ductus arteriosus
how do you treat Persistent pulmonary hypertension in a newborn
treat the cause of the lungs
inotropes for systemic circulation
gas for pulmonary
hwo does the site of heamatogenesis change
yolk sac - liver - spleen - bone marrow
what do foetuses produce in response to low saturation levels
EPO
what happens to haemoglobin when the baby starts to breath
EPO production reduces
haemoglobin changes shape
what is special about foetal haemoglobin
higher affinity for oxygen
why dod new borns get cold quick
high surface area to volume ratio
how do you overcome low surface area of babies when cold
tuck them up
what do babies have to generate heat
brown fat
what makes it harder for babies to cope with temperature
hypoxic
low sugar
how can babies store energy
in the liver
what alternate thing can babies use as an energy source
fatty acids and ketones
example when babies cant use the alternate energy supply
MCAD - medium chain acetylcholine deficiency
how might a diabetic mum affect baby
pancreas produces loads of insulin
once born gluclose plummets
how do kidney change in he first few days of life
reduce ECF in the first few days
GFR increases
tubular function increase
