Neonatology Flashcards
Which congenital heart lesions are cyanotic? (3)
Those that involve R–>L shunts (blue)
- Tetralogy of Fallot (5%)
- Transposition of great arteries (5%)
Common mixing
- AVSD complete (breathless and blue) – 2%
Which congenital heart lesions are acyanotic? (5)
Generally those with L–>R shunt (breathless)
- VSD (30%)
- ASD (7%)
- Persistent arterial duct (12%)
→ Outflow obstruction if not severe (asymptomatic with murmur)
- PS (7%)
- AS (5%)
- Severe outflow obstruction will present with collapse and shock
Common heart conditions associated with Down syndrome? (2)
- AVSD
- VSD
30% incidence
Common heart conditions associated with Turner syndrome? (2)
- Aortic valve stenosis
- Coarctation of the aorta
15% incidence
RFs for neonatal infection? (6)
- Maternal pyrexia
- PROM
- Prematurity
- Evidence of chorioamnionitis
- Maternal GBS colonization
- Foul smelling liquor
RFs for neonatal GBS infection? (4)
- PPROM
- Maternal fever in labour >38
- Maternal chorioamnionitis
- Previously infected infant
Management for mums and babies if GBS positive mum?
Mums:
- UK → Mothers with RFs for infection offered IV intrapartum abx
- USA/AUS → universal screening at 35-38w to identify carriers then those given IV abx
Babies:
- Usually appears as pneumonia/ sepsis/ meningitis
- Resp distress, apnoea, temp
- Ix → Septic screen: CXR, FBC, cultures, CRP, ?LP
- Rx → Abx immediately – amoxicillin/ benzylpenicillin
What does a septic screen consist of? (6)
FBC CRP Cultures CXR Urinalysis ?LP
Common viral (5) and bacterial (7) pathogens causing infection in newborn?
Viral:
- HSV
- CMV
- HIV
- HBV, HCV
- Rubella
Bacterial:
- GBS
- E Coli
- Gonorrhoea
- Treponema
- Listeria
- Other gram neg
- Atypical → chlamydia, ureaplasma
Most common congenital infection?
CMV
3 types of presentation of congenital CMV?
CID - 5%
- Most severe
- IUGR, hepatosplenomegaly, thrombocytopenia
- 90% neurological sequalae
‘Asymptomatic’ 90%
- Subtle IUGR
Present later in life with neurological sequalae - 5%
- Eg hearing loss
Features of congenital rubella infection?
- Rarely seen now
- Antenatal surveillance – must be confirmed serologically – clinical diagnosis unreliable
- Risk and extent of fetal damage determined by gestational age at onset of maternal infection
- Infection <8w gestation → deafness, congenital heart disease + cataracts in >80%
- 30% of fetuses of mothers infected at 13-16w have impaired hearing
- > 18w – risk to fetus minimal
- Congenital rubella = preventable due to MMR
Management with known maternal HIV?
If undetectable viral load:
- IV ZDV 4h before LSCSS, till cord clamped
- Neonatal ZDV monotherapy for 4w
- Viral PCR at birth, 1m, 3m, 12m
Detectable viral load:
- HAART/ Regimens for mother
- Triple therapy (ZDV + LZMU + NVP)
Clinical features of neonatal sepsis? (many)
- Fever or temp instability or hypothermia
- Poor feeding
- Vomiting
- Apnoea and bradycardia
- Respiratory distress
- Abdo distension
- Jaundice
- Neutropenia
- Hypo/hyperglycaemia
- Shock
- Irritability
- Seizures
- Lethargy, drowsiness
Causes of sticky eyes in neonatal period? (4)
Sticky eyes common in neonatal period – starts day 3, cleaning with saline/water works
Staph/strep - more troublesome discharge with redness
–> abx eye ointment e.g. neomycin
Gonococcal infection - purulent discharge & eyelid swelling in 1st 24h (can lead to blindness)
–> gram stain & culture –> 3rd gen IV cephalosporin
Chlamydia - purulent discharge & eyelid swelling at 1-2w
–> immunofluorescent staining –> oral erythromycin for 2w
Features and management of neonatal HSV?
- Uncommon
- Risk to infant with primary genital infection = 40%
- Risk to infant with recurrent maternal infection <3%
- Most infants infected unexpected as mother asymptomatic
- RF = preterm
- Presentation at any age ≤4w → localized herpetic lesions on skin or eye, or with encephalitis or disseminated disease
- Mortality with localized disease = low
- Disseminated disease mortality = high even with acyclovir
- -> If mother has primary or active recurrent disease at time of delivery → LSCS
- If mother has had in past but not active → acyclovir + vaginal delivery
Define SGA and IUGR?
SGA = birth weight <10th centile
IUGR = fails to meet genetically determined growth potential
What is asymmetrical IUGR?
- Asymmetrical (more common) – abdo circumeference lies on lower centile than head
- Due to placenta failing to provide adequate nutrition late in pregnancy
- Asymmetrical associated with utero-placental dysfunction due to: pre-eclampsia, multiple pregnancy, smoking, idiopathic
- These infants rapidly put on weight after birth
Features/ causes of symmetrical IUGR?
- Symmetrical → prolonged period of IUGR
- Usually small but normal fetes
- May be fetal chromosomal disorder or syndrome, congenital infection, maternal drug/ alcohol use, chronic medical condition or malnutrition
- More likely to remain small permanently
Common causes of asymmetrical IUGR? (4)
- Pre-eclampsia
- Multiple pregnancy
- Smoking
- Idiopathic
Common causes of symmetrical IUGR? (6)
- Normal but small fetus
- Fetal chromosomal disorder/syndrome
- Congenital infection
- Maternal drug/ alcohol use
- Chronic medical condition
- Malnutrition
Short-term complications from IUGR?
- Intrauterine hypoxia
- ‘Unexplained’ intrauterine death
- Asphyxia during labour/ delivery
After birth complications of IUGR? (4)
- Hypothermia as large SA
- Hypoglycaemia from poor fat and glycogen stores
- Hypocalcaemia
- Polycythaemia (venous haematocrit >0.65)
Name the pulmonary causes of neonatal respiratory distress?
Common (1)
Less common (6)
Rare (5)
Common:
- Transient tachypnoea of newborn
Less common:
- Meconium aspiration
- Pneumonia
- Respiratory distress syndrome
- Pneumothorax
- Persistent pulmonary HTN of newborn
- Milk aspiration
Rare:
- Diaphragmatic hernia
- Tracheo-oesophageal fistula (TOF)
- Pulmonary hypoplasia
- Airways obstruction eg choanal atresia
- Pulmonary haemorrhage
Signs of newborn respiratory distress? (4)
- Tachypnoea (>60 breaths/min)
- Laboured breathing – chest wall recession (esp sternal and subcostal) and nasal flaring
- Expiratory grunting
- Cyanosis if severe
Non-pulmonary causes of respiratory distress in the newborn? (4)
- Congenital heart disease
- Intracranial birth trauma/ encephalopathy
- Severe anaemia
- Metabolic acidosis
What is transient tachypnoea of the newborn?
- By far commonest cause of neonatal resp distress
- Caused by delay in resorption of lung liquid
- More common after C-section
- CXR may show fluid in horizontal fissure
- Additional ambient O2 may be required
- Usually settles within 1d but can take several to resolve completely
- Diagnosis made after consideration and exclusion of other causes
In what % is meconium passed before birth?
8-20%
- Rarely in preterm
Predispositions to neonatal pneumonia? (3)
- PROM
- Chorioamnionitis
- Low birth weight
What is persistent pulmonary HTN of newborn associated with? (4)
Birth asphyxia
Meconium aspiration
Septicaemia
RDS
Management of persistent pulmonary HTN of newborn?
- Most need mechanical ventilation/circulatory support
- Inhaled NO (potent vasodilator) often beneficial
- High frequency or oscillatory ventilation sometimes helpful
- Extracorporeal membrane oxygenation (ECMO) – placed on heart and lung bypass for several days – indicated for severe but reversible cases
Management of diaphragmatic hernia in newborn?
- Large NG tube passed and suction applied to prevent distension of intrathoracic bowel
- After stabilization, hernia repaired surgically
- Most infants with this condition main problem = pulmonary hypoplasia – compression by herniated viscera prevented development of lung
- If lungs hypoplastic → high mortality
2 things to look for on examination for heart failure?
Femoral pulses - coarctation/interruption of arch important causes
Hepatomegaly - due to venous congestion - useful sign
Common medical problems of preterm infants? (many)
- Need for resus at birth
- Resp - RDS, pneumothorax, apnoea + bradycardia
- Hypotension
- PDA
- Temp control
- Metabolic - hypoglycaemia/calcaemia, osteopenia
- Nutrition
- Infection
- Jaundice
- IVH/ periventricular leukomalacia
- NEC
- Retinopathy of prem
- Anaemia of prem
- Bronchopulmonary dysplasia
- Inguinal hernias
What 3 factors largely determine a premature neonates course and outcome?
- Gestational age at delivery
- Severity of respiratory disease
- Episodes of infection
What is respiratory distress syndrome?
Deficiency of surfactant, which lowers surface tension
- Deficiency → widespread alveolar collapse and inadequate gas exchange
Clinical signs of RDS? (4)
Within 4h of birth
- Tachypnoea >60
- Chest wall recessions (sternal and subcostal) + nasal flaring
- Expiratory grunting
- Cyanosis if severe
Diagnosis of RDS?
CXR –> characteristic
- Diffuse granular/ground glass appearance of lungs
- Air bronchogram
- Indistinct heart border or obscured completely if severe
Management of RDS? (4)
- Prophylactic glucocorticoids given antenatally if preterm delivery anticipated
- Raised ambient O2 +/- CPAP via nasal cannulae or artificial ventilation via tracheal tube
- High-flow humidified O2 therapy to wean babies from added O2 therapy
- Surfactant therapy derived from calf/pig lung instilled directly to lung via tracheal tube – reduces mortality by 40%
Presentation of NEC? (5)
- Infant stops tolerating feeds
- Milk aspirated from stomach and may be vomiting –pos bile-stained
- Abdo distension
- Stool sometimes contains fresh blood
- Infant may rapidly become shocked → require artificial ventilation because of abdo distension + pain
Management fo NEC?
- Stop oral feeding
- Broad spectrum abx
- Parenteral nutrition always needed
- Artificial ventilation and circulatory support often needed
- Surgery performed for bowel perforation
- Long-term sequalae = development of strictures and malabsorption if extensive bowel resection has been necessary
Mortality of NEC?
20%
RFs for hypoglycaemia in neonates? (7)
IUGR Preterm Maternal DM Large-for-dates Hypothermic Polycythaemic Ill for any reason
What level of glucose is hypoglycaemic in newborn?
<2.6mmol/L (no confirmed definition)
Sx of hypoglycaemia in neonates? (5)
- Jitteryness
- Irritability
- Apnoea
- Lethargy/ drowsiness
- Seizures
Management of hypoglycaemia in neonate?
- Often preventable by early & frequent milk feeding
- In high risk → monitor blood glucose reg
- IV 10% glucose if symptomatic or 2 low values + adequate feeding, or 1 v low value
- High conc IV glucose via central venous catheter to avoid extravasation into tissues – may cause skin necrosis and reactive hypoglycaemia
- If difficulty/delay in infusion - give glucagon or hydrocortisone
Treatment of apnoea of prematurity? (3)
- Physical stim often triggers breathing to be restarted
- Can use respiratory stimulant e.g. theophylline or caffine
- Sometimes CPAP required
Leading cause of preventable blindness?
Retinopathy of prematurity
- Raised risk if uncontrolled use of high conc O2
What % of infants <32w have an IVH?
10%
- Raised risk the smaller/earlier they are
Presentation of IVH in neonate?
- Most within 72h of birth
- 50% asymptomatic –> small and harmless
Larger bleeds may present as:
- Circulatory collapse
- Bulging fontanelle (↑ICP)
- Neurological (seizures)
- Anaemia
- Jaundice (↑ breakdown of bleed)
- Apnoea
- Lethargy
- Poor muscle tone
How is IVH confirmed?
Cranial USS
Management of IVH in neonate? (2)
- Supportive treatment- correct acidosis, anaemia, hypotension
- May need ventriculoperitoneal shunt
At what gestational age can infants swallow and suck?
35-36w
–> <35w NG feeds
Why are mothers encouraged to breast feed esp in preterms? (2)
- NEC with formula
- Septicaemia with parenteral feeds
What is bronchopulmonary dysplasia?
- When infants have O2 requirement at post-menstrual age of 36w
- Lung damage comes from pressure and volume trauma from artificial ventilation, oxygen toxicity and infection
What % of v low birthweight infants develop CP?
5-10%
What is classed as a very low birthweight?
<1.5kg
How is lung liquid reabsorbed when baby is born?
Chest compression during birth squeezes out 1/3
Release of adrenaline promotes reabsorption of 2/3
Timeframes for baby to
a) open bowels
b) pass urine
c) regain birth weight?
Bowels – usually within 6h or before birth but up to 24h
Bladder – up to 24h
Weight – newborns lose 7-10% weight but should regain it in 2w
2 RFs for baby vitamin K deficiency after birth?
- Mum on anti-epileptics
- Liver disease of baby
What can vitamin K deficiency lead to?
Haemorrhagic disease of newborn
- ↓ vitamin K dependent clotting factors
- Occurs either early (during 1st week) or late (1-8w)
- Haemorrhage can be mild e.g. bruising/ haematemesis/ melaena/ prolonged bleeding from umbilical stump/ after circumcision
- If severe can be intercranial haemorrhage (1/2 permanently disabled or die)
- Breast milk has ↓ vit K, formula milk much higher
When is the Guthrie test carried out?
Day 5-9
What is tested for on the Guthrie test? (9)
- CF
- Hypothyroidism
- Sickle cell
- Thalassaemia
- PKU
- MCADD (medium-chain acyl-CoA dehydrogenase deficiency)
- MSUD (maple syrup urine disease)
- IVA (isovaleric acidaemia)
- GA1 (glutaric aciduria type 1)
- HCU (homocystinuria (pyridoxine unresponsive)
What is checked for antenatally with maternal blood sample? (7)
Infections
- Hepatitis B
- Syphilis
- Rubella
- HIV infection
Rhesus group
NTDs risk
Downs risk
What is checked for at antenatal USS? (5)
- Gestational age
- Multiple pregnancies
- Structural malformation
- Fetal growth
- Amniotic fluid volume
What may lead to oligohydramnios? (3)
Reduced urine production - kidney problem
PROM
Severe IUGR
What is polyhydramnios associated with? (2)
Maternal DM
GI atresia in fetus
RFs for serious jaundice in newborn? (6)
- Low birth weight
- Breastfed
- Prev sibling with neonatal jaundice
- Visible jaundice in 24h
- Diabetic mum
- East Asian
Name 8 common newborn problems?
Erythema toxicum Mongolian blue spots Capillary haemangiomas Physiological jaundice Feeding difficulties Small for gestational age Birth trauma - cephalohaematoma, brachial plexus injury Sticky eye
What is erythema toxicum?
- Also called neonatal urticaria
- Common rash appearing at 2-3d of age
- White pinpoint papules at centre of erythematous base
- This fluid contains eosinophils and lesions are concentrated on trunk
- Come and go at different sites
What are capillary haemangiomas?
- Pink macules on upper eyelids, mid-forehead and nape of neck are common and arise from distension of the dermal capillaries
- Those on eyelids gradually fade over first year
- Those on neck become covered in hair
What is a cephalohaematoma?
- = Haematoma from bleeding below periosteum, confined within margins of skull sutures
- Usually involves parietal bone
- Centre of the haematoma feels soft
- Resolves over several weeks
Name some possible sensitising events in rhesus disease of newborn? (8)
Labour (86%) C section Miscarraige Abortion Amniocentesis Ectopic pregnancy Abdo trauma ECV
Sx of rhesus disease? (4)
Anaemia
Hydrops
Hepatosplenomegaly
Jaundice
What is ABO incompatability?
- More common than rhesus haemolytic disease
- Most ABO antibodies = IgM and do not cross placenta
- Some group O women have IgG anti-A haemolysin in blood which can cross placenta and haemolyse RBCs of group A infant
- Occasionally, group B infants affected by anti-B haemolysins
- Haemolysis can cause severe jaundice but usually less severe than rhesus disease
- Infant’s Hb level usually normal or slightly reduced and, in contrast to rhesus disease, hepatosplenomegaly absent
- Direct antibody test (Coombs’ test), which demonstrates antibody on surface of red cells, is positive
- Jaundice usually peaks in first 12–72h
Management of ABO incompatibility?
Antenatal
- Intrauterine transfusion
- Early induction of labour when pulmonary maturity has been obtained
- Mothers may also undergo plasma exchange to lower circulating antibodies by 75%
Post-natal
- Depends on severity of condition
- May simply involve treating jaundice with phototherapy
- May be cause for transfusion with RBCs and also bicarbonate to correct an acidosis
RFs for congenital abnormalities? (4)
- Maternal and paternal age
- Infections (TORCH – toxoplasmosis, others, rubella, CMV and HSV)
- Toxins e.g. alcohol, smoking, mercury or prescription drugs
- Dietary deficiencies e.g. folic acid
MANY more, these are important ones
What is CHARGE syndrome?
Genetic syndrome that is an acronym to describe a set of unusual congenital features seen in many newborn children
- Coloboma of eye (a hole in one of the eyes structures e.g. the iris, retina, choroid or optic disc)
- Heart defects
- Atresia of nasal choanae
- Retardation of growth and/or development
- Genital and/or urinary abnormalities
- Ear abnormalities and deafness
This syndrome = leading cause of congenital deaf-blindness
What is VACTERL syndrome?
Syndrome (or an association) of birth defects
Thought to be genetic and associated with trisomy 18 or more frequently with diabetic mothers
- Vertebral defects (hypoplastic vertebrae and scoliosis)
- Anal atresia
- CV abnormalities (ASD, VSD and Tetralogy of fallot)
- Tracheoesophageal fistula
- Esophageal atresia
- Renal anomalies (usually one umbilical vein instead of two which causes problems – outflow obstruction, reflux and kidney failure)
- Limb defects (hypoplastic thumbs, extra digits, fusion of digits etc)
Most will have normal development and intelligence but can be quite small
What is Patau syndrome and clinical features (6)?
Trisomy 13
- Least common and most severe of trisomies
- Much more likely to affect females
- RFs: affected close family, maternal age
- Most affected babies die in infancy – median survival = 2.5d
Clinical features
- Structural defect of brain
- Scalp defects
- Small eyes and other eye defects
- Cleft lip and palate
- Polydactyly
- Cardiac and renal malformations
What is Edward’s syndrome and clinical features?
Trisomy 18
- Poor prognosis – mean life expectancy 4d, 5-10% survive beyond 1y
Clinical features
- Low birth weight
- Prominent occiput
- Small mouth and chin
- Short sternum
- Flexed, overlapping fingers
- ‘Rockerbottom’ feet
- Cardiac and renal malformations
Types of NTDs? (5)
Anencephaly
Encephalocele
Spina Biffida
- Occulta
- Cystica (meningocele, myelomeningocele)
What is anencephaly?
- Failure of development of most of cranium and brain
- Affected infants stillborn or die shortly after birth
- Detected on antenatal USS and TOP usually performed
What is encephalocele?
- Extrusion of brain and meninges through midline skull defect
- Can be corrected surgically
- However, often underlying associated cerebral malformations
What does spina bifida mean?
- Failure of fusion of vertebral arch
What is a meningocele?
Type of NTD
- Skin and meninges form out-pouching
- Unlikely to suffer long-term health problems
- May be underlying tethering of cord - with growth, may cause neurological deficits of bladder function and lower limbs
- Extent of underlying disease can be delineated using USS +/or MRI scans
- Neurosurgical relief of tethering usually indicated
What is a myelomeningocele?
Type of NTD
- Communication b/w surface and meninges, along with some neural tissue (a neural plaque)
- Associated with many complications such as paralysis, sensory loss, muscle imbalance, neuropathic bladder and bowel, scoliosis and hydrocephalus
- Most severe have lesions above L3
- → Unable to walk, have scoliosis, neuropathic bladder and bowel, hydronephrosis and frequently develop hydrocephalus
What may a disorder of sexual differentiation be secondary to? (4)
XS androgens producing virilisation in a female
- Mostly due to congenital adrenal hyperplasia
Inadequate androgen action, producing under virilisation in a male
Gonadotrophin insufficiency
–> small penis and cryptochidism
Ovotesticular disorder of sex development (DSD)
- XY and XX cells
What is congenital adrenal hyperplasia?
- Number of autosomal recessive disorders of adrenal steroid biosynthesis result in congenital adrenal hyperplasia
- RF = consanguineous marriages
- > 90% have deficiency of enzyme 21hydroxylase→ needed for cortisol biosynthesis
- 80% also unable to produce aldosterone→ salt loss (low Na and high K+)
- In fetus, resulting cortisol deficiency stims pituitary to produce ACTH, which drives overproduction of adrenal androgens
Clinical features of congenital adrenal hyperplasia? (4)
- Virilisation of external genitalia
- Salt losing adrenal crisis (1-3weeks old) in 80% males –> vomiting, wt loss, floppiness, circulatory collapse
- Tall stature in 20% non-salt losing males
- M+F non-salt losers –> muscular build, adult body odour, pubic hair (i.e. precocious pubarche)
Diagnosis of congenital adrenal hyperplasia?
- Finding markedly raised levels of metabolic precursor 17αhydroxyprogesterone in blood
Management of congenital adrenal hyperplasia?
Females may need corrective surgery
Males in salt-losing crises need saline, dextrose and hydrocortisone IV
Long term:
- Lifelong glucocorticoids to suppress ACTH (+ hence testosterone) - allow normal growth/development
- Mineralocorticoids if salt loss (fludrocortisone)
- Monitoring of growth, skeletal maturity and plasma androgens and 17αhydroxyprogesterone
- Additional hormone replacement to cover illness/surgery, as unable to mount cortisol response
Causes of haemolytic diseases of the newborn? (4)
- Rhesus haemolytic disease
- ABO incompatibility
- G6PD deficiency
- Spherocytosis
Causes of significant hypoxic event that may lead to HIE? (5)
- Failure of gas exchange across placenta – XS or prolonged uterine contractions, placental abruption, ruptured uterus
- Interruption of umbilical blood flow – cord compression inc shoulder dystocia, cord prolapse
- Inadequate maternal placental perfusion, maternal hypotension or HTN – often with IUGR
- Compromised fetus – anemia, IUGR
- Failure of cardiorespiratory adaptation at birth – failure to breathe
Classification of HIE?
- Mild → infant irritable, responds XS to stimulation, may have staring of eyes and hyperventilation and impaired feeding
- Moderate → marked abnormalities of tone and movement, cannot feed and may have seizures
- Severe → no normal spontaneous movements or response to pain; tone in limbs may fluctuate between hypotonia and hypertonia; seizures prolonged and often refractory to treatment; multiorgan failure present
Prognosis of HIE?
Mild HIE
- Complete recovery expected
Moderate HIE
- If recovered fully on clinical neurological examination and feeding normally by 2w → excellent long-term prognosis
- If clinical abnormalities persist beyond 2w→ full recovery unlikely
Severe HIE
- Mortality = 30–40%
- Of survivors, >80% have neurodevelopmental disabilities, esp CP
- If MRI at 4–14d in term infant shows sig abnormalities (bilat abnormalities in basal ganglia and thalamus and lack of myelin in posterior limb of internal capsule) →v high risk of later CP
What can HIE present with if there is multi-organ dysfunction?
Encephalopathy Respiratory failure Myocardial dysfunction Metabolic --> Hypo-glycaemia, calcaemia, natraemia Renal failure DIC
