Prematurity Flashcards
What proportion of neonatal deaths are related to prematurity?
Around 50%
Define preterm and and its subgroups. What is the incidence of each?
Preterm = less than 37 weeks
- extremely preterm (less than 28 weeks) 0.38% - NZ 2012
- very preterm (28 to 32 weeks) 0.6% NZ 2012
- moderate to late preterm (32 to 37 weeks) 5% NZ 2012
What factors affect survival in extremely premature infants?
Gestational age
Birthweight
Gender
Plurality
Presence of other comorbidity e.g. infection/congenital abnormality
Administration of steroids prior to delivery
Administration of magnesium sulphate prior to delivery
Delivery in tertiary centre with level 3 NICU care
What are the short term complications/risks of prematurity?
Respiratory:
- Respiratory distress syndrome
- Apnoea of prematurity
- Transient tachypnoea of the newborn
- Bronchopulmonary dysplasia
Cardiac:
- Persistant ductus arteriosus
Gastrointestinal:
- Feeding intolerance
- Necrotising enterocolitis
- Hypoglycaemia
Neurological:
- Intraventricular haemorrhage
- Periventricular leukomalacia
Systemic:
- Sepsis
- Hypothermia
- Jaundice
What are the long term complications of extreme prematurity?
1 in 6 survivors will have substantial neurodevelopmental disability
Increased likelihood of poorer school performance
Often shorter, lighter
Raised BP by 2mmHg which increases cardiovascular risk factors
Increased risk of chronic lung disease
What are the survival and disability rates for periviable infants born at 24/40?
Survival (5 year RNSH data):
• 24/40 = 48%
Disability rate:
• 24/40 = approx 24%
What is the data around survival and cognitive / developmental impairment for extremely preterm infants born <28/40?
Premature <28/40:
Survival = 90%
- 70% = normal development
- 20% = mild or moderate developmental problem
- 10% = severe developmental impairment
What re the long term complications for very premature infants?
Very preterm (28-32)
Most babies will survive (>95%), especially if they have steroids
Increased likelihood of the issues of extreme prematurity but less than EP
What are the long term complications of moderate-late preterm?
> 32/40
Most children will do well however they are still at an increased risk of the issues listed with EP when compared to term children
What is the cause and management of apnoea of prematurity?
Immaturity central control centres of respiratory drive. Poor control/ laxity of upper airways. It is inversely corrected to gestation.
Can be a sign of infection, IVH or hypoglycaemia.
Extremely premature babies are given prophylactic caffeine.
Management is with caffeine citrate, CPAP, +/- IPV with intubation.
What is the cause and incidence of bronchopulmonary dysplasia?
Most common cause of chronic lung disease.
Incidence of 48% below 27/40.
Due to lung immaturity, respiratory distress, oxygen therapy and barotrauma from mechanical ventilation.
What is the definition and presentation of periventricular leukomalacia?
Lesion found in the immature white matter of premature babies
May not clinically manifest for weeks to months.
May present as spasticity or cognitive disability.
Can be seen on cerebral USS.
What is the definition and mortality rate of NEC?
Ulcerative inflammation of the intestinal wall, which both infective and ischemic aetiology.
Mortality rate of 40%.
Risk of perforation requiring surgical intervention.
What are the risk factors for intraventricular haemorrhage?
How is it diagnosed?
Affects 15-20% of babies born before 32/40.
Risk factors: infection, lack of steroids, mode of delivery, neonatal transport.
Diagnosed with head USS.
What is periventricular leukomalacia?What is it associated with?
Hypoxia and ischemia of watershed areas of brain white matter
Associated with cerebral palsy - spasticity and neurodevelopmental delay
