6: Preterm infants Flashcards
Before which point in gestation is a birth pre-term?
37 weeks
Birth before ___ weeks is incompatible with life.
22 weeks
Fatal birth before 22 weeks is also known as what?
Foetal loss
or Miscarriage
At which point in gestation is a birth at term?
38 - 42 weeks
Pre-term babies are more likely to have a (high / low) birth weight.
low birth weight
Which lifestyle choice has an effect on the rates of pre-term delivery?
Smoking
Smoking ban saw a 10% decrease in pre-term births
What is a neonatal death?
Death within the first four weeks of life
Which type of pregnancy is associated with pre-term birth?
Multiple pregnancy
Ferguson reflex - increased distension of uterine walls
The majority of pre-term births are ___ in origin.
idiopathic
nobody knows why
Having more than one baby in the womb is a common cause of ___ delivery.
pre-term
A history of ___ delivery increases a woman’s risk of pre-term delivery.
pre-term delivery
cumulative effect
Pre-term babies are more vulnerable to ___ stress, have less developed ___ and are more likely to be (hyper/hypo)glycaemic.
vulnerable to cold stress - less brown fat
less developed lung - less surfactant
hypoglycaemic - less glycogen reserves
What is the purpose of delayed cord clamping?
Allows maximum volume of blood to transfer from mother to baby
–> reduce chances of anaemia, hypovolaemia
What does cold stress lead to in premature babies?
Hypothermia
How does hypothermia cause hypoglycaemia in babies?
Increased non-shivering thermogenesis
Which uses glycogen stores
When glycogen is depleted, free circulating glucose is used up
> Hypoglycaemia
How does hypothermia cause hypoxia in premature babies?
Increased oxygen demand due to increased thermogenesis
> Hypoxia and metabolic acidosis (anaerobic respiration)
How are pre-term babies initially fed?
Parenteral nutrition
What is the risk of parenteral feeding in pre-term babies?
Infection
As it involves IV access
Which disease, involving widespread ischaemia of the bowel, can be treated using parenteral nutrition?
Necrotising enterocolitis (NEC)
What is the ideal form of feeding for babies?
Exclusive breastfeeding
If a mother can’t breastfeed, what forms of nutrition can be offered to pre-term babies?
Donor milk
Formula milk
What can untreated infection cause in neonates?
Neonatal sepsis
What are the two forms of neonatal sepsis seen in babies?
Early onset - probably acquired during pregnancy / birth
Late onset - acquired post-birth
What are the most common bacteria causing
a) early-onset
b) late-onset neonatal sepsis?
a) Group B Strep, Coliforms
b) Coagulase negative Staph i.e Staph epidermidis
What causes respiratory distress in pre-mature babies?
Lack of pulmonary surfactant
Which abnormal breathing patterns can pre-mature babies present with?
Transient tachpynoea
Apnoea
How does a baby with respiratory distress present?
Cyanosis
Tachypnoea
Intercostal/sternal recession
Nasal flaring
Grunting
How is a baby with respiratory distress managed?
Steroids
Ventilation
CPAP
What appearance do the lungs have on CXR in a baby with respiratory distress?
Ground glass appearance
None of the blood in the foetal circulation has a large oxygen concentration.
What helps a baby to get around this?
Foetal Hb
Which type of brain bleed are pre-term babies at risk of?
How is a baby’s risk reduced?
Intraventricular haemorrhage
Magnesium sulphate
Which GI condition is seen almost exclusively in pre-term babies and carries a high mortality rate?
Necrotising enterocolitis (NEC)
What are the signs of NEC on an abdominal X-ray?
Dilated bowel loops
Pneumoperitoneum
The greater a baby’s gestational age (up to term), the (better / worse) their chances of survival.
greater gestational age > greater likelihood of survival
so every week in the womb counts
