Neonates Flashcards
What is the incidence of duodenal atresia?
1/5000 (higher in Downs syndrome)
What is the age at presentation of duodenal atresia?
A few hours after birth
How is duodenal atresia diagnosed?
Abdominal x-ray showing double bubble sign, contrast studies may confirm the diagnosis
What is cause of malrotation with volvulus?
Incomplete rotation during embryogenesis
What is the age at presentation for malrotation with volvulus?
Usually 3-7 days after birth, volvulus with compromised circulation may result in peritoneal signs and haemodynamic instability
What is the diagnostic test for malrotation with volvulus?
Upper GI contrast study may show duodo-jejunal flexure is more medially placed, USS may show abnormal orientation of the superior mesenteric artery and vein
What does this USS demonstrate?
Malrotation with volvulus
What is the incidence of jejunal/ ileal atresia?
1/3000, usually caused by vascular insufficiency in utero
What is the age at presentation for jejunal/ ileal atresia?
Usually within 24 hours of birth
What is the diagnostic test for jejunal/ ileal atresia?
Abdominal x-ray showing air-fluid levels
What is the incidence of meconium ileus?
15-20% of neonates with cystic fibrosis
Otherwise, 1/5000
What is the age at presentation of meconium ileus?
24-48 hours of life, abdominal distension and bilious vomiting
What is the diagnostic test for meconium ileus?
Air-fluid levels on abdominal x-ray, heel prick/ sweat test to confirm cystic fibrosis
What is the incidence of necrotising enterocolitis?
Up to 2.4/1000 births, risks are increased with prematurity and inter-current illness
What is the age at presentation for necrotising enterocolitis?
Usually 2nd week of life
What is the diagnostic test for necrotising enterocolitis?
Dilated bowel loops on abdominal x-ray, pneumatosis and portal venous air
What are the neonatal causes of hypotonia?
- Neonatal sepsis
- Werdnig-Hoffman disease (spinal muscular atrophy type 1)
- Hypothyroidism
- Prader-Willi
What are the maternal causes of neonatal hypotonia?
- Maternal drugs eg. benzodiazepines
- Maternal myasthenia gravis
What is the figure most commonly used for neonatal hypoglycaemia?
<2.6mmol/L
Why does neonatal hypoglycaemia usually not cause any sequelae?
Because neonates are able to use alternative fuels like ketones and lactate
What can cause persistent/ severe hypoglycaemia in neonates?
- Preterm birth (<37 weeks)
- Maternal diabetes mellitus
- Intrauterine growth restriction (IUGR)
- Hypothermia
- Neonatal sepsis
- Inborn errors of metabolism
- Nesidioblastosis
- Beckwith-Wiedemann syndrome
What are the features of neonatal hypoglycaemia?
May be asymptomatic
Autonomic:
- Jitteriness
- Irritability
- Tachypnoea
- Pallor
Neuroglycopenic
- Poor feeding/ sucking
- Weak cry
- Drowsy
- Hypotonia
- Seizures
Other features may include
- Apnoea
- Hypothermia
What is the management of asymptomatic neonatal jaundice?
- Encourage normal feeding (breast or bottle)
- Monitor blood glucose
What is the management of symptomatic/ very low blood glucose in neonates?
- Admit to the neonatal unit
- IV 10% dextrose
What are the major congenital infections to be aware of?
- Rubella
- Toxoplasmosis
- Cytomegalovirus
What is the most common congenital infection in the UK?
Cytomegalovirus
Maternal infection is usually asymptomatic
What are the characteristic features of a neonate infected with rubella in utero?
- Sensorineural deafness
- Congenital cataracts
- Congenital heart disease (eg. patent ductus arteriosus)
- Glaucoma
What are some less common features of neonatal intrauterine rubella infection?
- Growth retardation
- Hepatosplenomegaly
- Purpuric skin lesions
- ‘Salt and pepper’ chorioretinitis
- Microphthalmia (unilateral or bilateral)
- Cerebral palsy
What are the features of toxoplasmosis infection of a neonate in utero?
- Cerebral calcification
- Chorioretinitis
- Hydrocephalus
What are some less common features of toxoplasmosis infection of a neonate in utero?
- Anaemia
- Hepatosplenomegaly
- Cerebral palsy
What are the characteristic features of a neonate infected with cytomegalovirus in utero?
- Low birth weight
- Purpuric skin lesions
- Sensorineural deafness
- Microcephaly
What are some other features of neonatal cytomegalovirus?
- Visual impairment
- Learning disability
- Encephalitis/ seizures
- Pneumonitis
- Hepatosplenomegaly
- Anaemia
- Jaundice
- Cerebral palsy