Neonatology Flashcards
At what week of development does the heart start to beat?
Week 4
->heart begins to develop in week 3 and starts to beat in week 4
Which vessel brings oxygenated blood to the foetus?
Umbilical vein
What is the saturation of oxygen in foetal blood?
60-70%
What are the functions of the ductus arteriosus?
-Protects lungs against circulatory overload
-Allows the right ventricle to strengthen
-Carries low oxygen saturated blood
Which two blood vessels does the ductus arteriosus conenct?
Pulmonary artery and aorta
Which two blood vessels does the ductus venosus connect?
Umbilical vein and IVC
What is normal HR in a newborn?
120-160 b/m
> 160 = tachycardia
<100 = bradycardia
What is the normal RR for a newborn?
30-60 / min
What is normal blood pressure for a newborn?
70/44
What is the normal temperature for a newborn?
37 +/- 0.5
How do babies thermoregulate?
Maternal thermoregulation in womb
Newborn babies cannot shiver so cold stress lead to lipolysis of brown fat and heat production.
It can be difficult to assess breathing in a newborn baby.
What can be done to assess breathing?
Blood gas determination e.g. PaCO2, PaO2
Trans-cutaneous pCO2/O2 measurement
How long can physiological jaundice last?
Appears on day 2-3
Disappears within 7-10 in term infants and 21 days in premature
10% weight loss of baby on day 1 is normal, why?
Loss is due to shift of interstitial fluid to intravascular
->normal for newborn not to pass urine in first 24hrs
What are some of the maternal causes of intra-uterine growth restriction causing babies to be born smaller?
Maternal smoking
Maternal Pre-eclamptic toxaemia
What are some of the foetal causes of intra-uterine growth restriction causing babies to be born smaller?
Chromosomal e.g. Edward’s syndrome
Foetal infection e.g. cytomegalovirus
What are some of the placental causes of intra-uterine growth restriction causing babies to be born smaller?
Placenta abruption
What are some of the other causes of intra-uterine growth restriction causing babies to be born smaller?
Multiple pregnancy
->less room to grow
Why do a lot of preterm babies develop respiratory distress syndrome?
Surfactant deficiency in the lungs
->surfactant only produced at 38wks gestation
How is RDS prevented in preterm children?
Antenatal steroids to mother
->triggers production of surfactant
Treatment of RDS in the preterm infant?
Early treatment with surfactant
Early extubation
Non-invasive support
Minimal ventilation
What is the ultimate complication of RDS?
BPD/chronic lung disease
In preterm infants, some minor respiratory problems can occur.
Apnoea is one, were breathing seems to stop. This is normal for 10 seconds or so, but if longer than 20secs, requires treating.
What is the treatment?
Caffeine to stimulate breathing centre in the medulla oblongata
How do you prevent intraventricular haemorrhages in preterm newborns?
AN steroids to mother
Treatment of intraventricular haemorrhage in newborns?
Symptomatic
How quickly does the ductus arteriosus close in a term baby?
6-72hrs
->always open in preterm neonates
What are some of the consequences of patent ductus arteriosus in preterm neonates?
Worsening of respiratory symptoms
Retention of fluids
GI problems
