Normal Newborn Flashcards
What are the changes that occur after birth within the circulatory system?
As the newborn takes its first breath pulmonary vascular resistance drops.
More blood flow goes through the pulmonary vasculature and into the left side of the heart.
Concurrently blood flow to the right side of the heart is reduced as the umbilical vessels are clamped.
This creates a pressure change so that the pressure in the left atria exceeds the pressure in the right causing the foramen ovale (flap) to shut.
Due to the effects of prostaglandins the ductus arteriosus will shut within hours to days.
What are the changes that occur after birth in the respiratory system?
Chest compression during birth squeezes out a third of the liquid in the lung and the release of adrenaline promotes reabsorption of the rest.
Adrenaline triggers the release of surfactant.
Pulmonary vascular resistance drops with expansion of the alveoli after the first breath.
What are the time frames for the following to be achieved: pass urine, open bowels and regain birth weight?
Pass urine: within first 24hrs
Open bowels: usually within 6 hours but normal unto 24hrs
Regain birth weight: newborns lose ~ 10% of there birth weight but should regain it by 2 weeks.
Describe how to conduct a newborn baby check and what is being looked for?
General observation of posture and movement.
Birth weight and head circumference plotted.
Fontanelle: raised?
Face: looking for dysmorphic features.
Eyes: jaundice, red reflex (looking for congenital cataracts)
Mouth: sucking reflex and checking for cleft palate
Chest: lung and heart sounds 110-160bpm
Abdomen: liver is normal to lie 1-2cm under costal margin
Femoral pulses: Coarctation
Genitalia: check testes are descended in males
Anus: Check anus is present
Muscle tone, back and spine: Observe and feel
Hip examination: looking for developmental dysplasia of the hips (DDH)
Morrow reflex.
What is tested for on the guthrie (heel prick test)?
Day 5-9
- Phenylketonuria
- CF
- Hypothyroidism
- Haemaglobinopathies
- MCAD (medium-chain acyl-CoA dehydrogenase) deficiency.
MCAD deficiency is a rare inborn error of mitochondrial fatty acid metabolism causing acute illness.
Other than the newborn baby check and the guthrie test what other screens should be done in newborns?
The universal hearing screen.
It is used to detect severe hearing loss.
It is tested using evoked otoacoustic emission: an earphone produces a sound which evokes an echo or emission from the ear if cochlear function is normal.
At what age should a child’s eyes be moving simultaneously and what age should they have adult vision by?
By 6 weeks eyes should move simultaneously when following a light source.
By 12 weeks there should be no squint.
By 3-4 years of age they should have adult vision.
Why is vitamin K prophylaxis given?
Vitamin K deficiency may result in haemorrhagic disease of the newborn. This disorder can occur early, during the first week of life, or late, from 1 to 8 weeks of age.
In most cases haemorrhage is mild, however in some cases it can cause inter-cranial haemorrhage which can cause significant morbidity and mortality.
Breast milk is a poor source of Vitamin K so those on a purely breast milk diet are at an increased risk.
Which group of mothers are at particular risk of having a baby with postpartum Vitamin k deficient haemorrhagic disease of the newborn?
Mother’s that take anticonvulsants during pregnancy as they impair the synthesis of vitamin K-dependent clotting factors.
