Neonatology Flashcards
What are the causes of low alpha-fetoprotein?
Incorrect gestational age
Trisomy 21 (Downs syndrome)
Trisomy 18 (Edward syndrome)
What are the causes of raised alpha-fetoprotein?
Neural tube defects
Multiple pregnancy
Urinary obstruction
Placental abnormalities
Renal abnormalities
Cystic hygroma
Abdominal wall defects
Which condition is associated with a persistently open posterior fontanelle?
Hypothyroidism
When should the anterior fontanelle have fully closed?
18 months
Which nerve roots are affected in Erbs palsy?
C5 and C6 +/- C7
Which nerve roots are affected in Klumpkes palsy?
C8 and T1
What is the appearance in Erbs palsy?
Waiters tip
What is the appearance in Klumpkes palsy?
Claw hand
What does delayed umbilical cord separation possibly represent?
Leucocyte adhesion deficiency
What does hypospadias represent?
Urethral opening on the ventral aspect of the penis (underside)
What does epispadias represent?
Urethral opening on the dorsal aspect of the penis (upper-side)
What are the classical CXR findings of infants with transient tachypnoea of the newborn?
Hyperinflation
Prominent perihilar vascular markings
Fluid in the fissures
What are the classical CXR findings in meconium aspiration syndrome?
Hyperinflation
Air trapping
Streaky linear and patchy infiltrates
Acute atelectasis
What are the main findings of toxoplasmosis infection?
Hydrocephalus (large head)
Intracranial calcifications - diffuse
Chorioretinitis
What are the main findings of CMV infection?
Microcephaly
Periventricular intracranial calcifications
Chorioretinitis
Sensorineural hearing loss
What are the manifestations of congenital syphilis?
Prematurity/ low birth weight
Hutchinson teeth (concave appearance to top of tooth)
Snuffles
Hepatomegaly
Generalised lymphadenopathy
Maculopapular rash
Thrombocytopenia
Coombs negative haemolytic anaemia with hydros
What percentage of patients with CF will have a meconium ileus?
10-20%
What are radiographic findings of NEC?
Intramural gas (pneumonitis intestinalis)
Portal vessel gas
Which side does congenital diaphragmatic hernia commonly occur on?
Left side
What are the features of fetal alcohol syndrome?
Short palpebral fissures
Midface hypoplasia
Small eyes
Smooth philtrum
Thin upper lip
Microcephaly
Irritability
Intellectual impairment
Which teratogen is associated with orofacial clefts?
Carbamazepine
Which conditions are associated with lithium as a teratogen?
Ebsteins anomaly
Hypothyroidism
Nephrogenic diabetes insipidus
Macrosomia
Which conditions are associated with cocaine use as a teratogen?
Limb defect/ reduction
Intracranial haemorrhage
Leukomalacia
Gastroschisis
What shape is group B streptococcus?
Anaerobic, gram positive cocci
By what gestational age is epidermal maturation complete?
34 weeks
Which is the only antibody to cross the placenta?
IgG
What are ABO antibodies?
IgM
What is the most common type of congenital diaphragmatic hernia?
Bochdalek hernia (left sided) - a posterolateral defect in the diaphragm
The other type is a Morgagni hernia - far less common and anterior in the diaphragm (less likely to be symptomatic)
What are the risk factors for metabolic bone disease of prematurity?
Deprivation of fetal mineral accumulation (occurs in the third trimester)
Postnatal steroid administration
Postnatal diuretic administration
What is the pathophysiology of physiological jaundice?
In normal bilirubin metabolism, unconjugated bilirubin is bound to albumin in the plasma and transported to the liver. In the liver, it is conjugated to glucuronic acid in hepatocytes - this conjugation is catalysed by the enzyme glucoronyl transferase.
In newborn infants, the liver is immature and there are low levels of glucoronyl transferase. Hence leading to increased levels of unconjugated bilirubin circulating in the blood.
What are the criteria for cooling in HIE?
Section A criteria:
Apgars <5 @ 10 minutes
Acidosis of pH <7.0 @ 60 minutes
BE >16 within 60 minutes
Continued need for resuscitation @ 10 mins
Section B criteria:
Hypotonia
Altered consciousness
Abnormal primitive reflexes
Which 3 factors contribute to IVH?
Germinal matrix fragility due to prematurity
Fluctation of cerebral blood flow
Platelet and coagulation disorders
What type of immunoglobulins will be present if the mother has O type blood?
IgG - hence will pass through the placenta
What is the most common cause of unconjugated hyperbilirubinaemia?
Breast feeding
What type of immunoglobulins will be present if the mother has A/B type blood?
IgM - hence will not pass through the placenta
What is the pathophysiology of breastfeeding jaundice?
In the first week there is small volume being consumed and hence a caloric deprivation which leads to increased enterohepatic circulation and hence increased jaundice
What are the causes of unconjugated hyperbilirubinaemia?
Haemolysis
- ABO incompatibility
- Rhesus incompatibility
- Spherocytosis
- G6PD
Polycythaemia
Endocrine (hypothyroid/ hypopituitarism)
Metabolic conditions (Galactoseamia, Gilberts disease)
What are the causes of conjugated hyperbiliruinaemia?
Biliary atresia
Infections (Rubella, CMV, toxoplasmosis)
Viral hepatitis
Alagille Syndrome
Choledochal cyst
What is the pathophysiology of biliary atresia?
The progressive obliteration of the extra-hepatic biliary ducts which then leads to the obstruction of bile flow
What are the presenting symptoms of conjugated hyperbilirubinaemia?
Jaundice
Pale stools
Dark urine
At what gestation is the suck reflex usually established?
32-34 weeks
Which babies need screening for ROP?
BW <1500g
Born before 31 weeks gestation
When should screening for ROP occur?
If born <31 weeks then the first screening should either be between 31+1 and 31+6 weeks gestation or 4 weeks postnatal - whichever is later
If born after 31 weeks then the first screening should be at 36 weeks PMA or 4 weeks - whichever is sooner
Which conditions are tested for on heel prick newborn screening?
Congenital hypothyroidism (most prevalent)
Cystic fibrosis
Sickle cell disease
PKU
MCADD
Maple syrup urine
Homocystinuria
Isovalaeric academia
Glutaric acuduria type 1
What are the features of duodenal atresia?
Normal vomiting - if located above the ampulla of Vater
Bilious vomiting - if located below the ampulla of Vater
When is surfactant produced?
From 24 weeks until term
Secreted from type II pneumocytes
What is the treatment of umbilical granulomas?
Reassurance and review
What are the causes of hydros fetalis?
Fetomaternal haemorrhage - most common
Paroxysmal SVT
Turner syndrome
Intrauterine/ congenital infections
Who is Varicella Zoster Immunoglobulin recommended to?
All neonates delivered to mothers who develop varicella seven days before to seven days after delivery
What are the common features of congenital rubella infection?
Cataracts
Congenital heart defects
Deafness
What features are seen in congenital varicella infection?
Scarring (pale yellow dermatomal scars)
Limb hypoplasia
Microcephaly
Chorioretinitis
Corneal clouding
Optic atrophy
What is meconium staining in preterm labour strongly suggestive of?
Listeria Monocytogenes
What is the pathophysiology of persistent pulmonary HTN?
It is characterised by failure of the fall in PVR, resulting in shunting of blood from the right to the left, through the foramen ovale and/ or ductus arteriosus, causing bypassing of lungs and resultant severe hypoxia
What is the function of surfactant in pre-term infants?
Reduces the surface tension on the alveoli
What is the target range for tidal volumes?
4-6ml/kg
Increasing the tidal volume, will decrease the pCO2 and vice versa
What is the dose of adrenaline in NLS?
0.2ml/kg of 1:10,000 adrenaline - repeated evert 3-5 minutes
What is the pathophysiology behind fetal alcohol syndrome?
Alcohol crosses the placenta into the fetal blood which causes high alcohol levels in the fetus. This alcohol is metabolised much slower than in adults and it causes reduced oxygen delivery and poor nutrients to get to the fetus
What is the histopathology of Hirshsprungs disease?
Absence of ganglion cells in the submucosa or myenteric plexus (lies in the muscular layer between the longitudinal and circular layers)
What is the management of haemolytic disease of the newborn - patients presenting with bleeding having not received vitamin K?
IV vitamin K + fresh frozen plasma
What is the structure of fetal Hb?
2 alpha chains and 2 gamma chains
What are the causes of asymmetrical IUGR?
Most likely to be caused by poor placental function
Causes include maternal smoking and pre-eclampsia
What are the causes of symmetrical IUGR?
Most likely to be caused by intrauterine infections - TORCH infections
Which ventricle is accessed via the anterior fontanelle?
Lateral ventricles
