Neonatal illness and infections

Question 1

Legally ‘viable’ neonate

Answer 1

From 24 weeks

Question 2

Neonatal period

Answer 2

1-28 days after birth

Question 3

Perinatal period

Answer 3

24 weeks gestation to 7 days post birth

Question 4

Classification of babies

Answer 4

Preterm - <37 weeks (6-8% of babies)
Term 37 -42 weeks
Post dates Over 42 weeks

Question 5

Classification of baby weight

Answer 5

Low birth weight is <10 centile

Question 6

Infant mortality

Answer 6

Stillbirth is intrauterine death after 24 weeks
Abortion is fetal loss before 24 weeks
Infant mortality is 7/1000, neonatal mortality is 5/1000 and perinatal mortality is 8/1000

Question 7

Intra-uterine infections

Answer 7

Rubella - vaccinate before conception. Toxoplasmosis/syphilis/listeria - treat both in- and ex-utero. Hep B - vaccinate at birth. CMV/Herpes - treat after birth. HIV - treat mother before birth, C/S, treat baby after birth and avoid breast feeding

Question 8

Neonatal diabetes

Answer 8

Congenital abnormalities are increased
Increased birth weight w/ organomegaly and polycthaemia
Hypoglycaemia after birth
Respiratory distress syndrome (RDS)

Question 9

Transition from Intra-uterine to extra-uterine life

Answer 9

Cardiopulmonary switch - forming a double circulation and closing shunts (foramen ovale and DA). Establishment of enteral feeding with gut flora and Vit K (should be given a perinatal dose)
Temperature maintenance and infection prevention

Question 10

Apgar score

Answer 10

2 1 0
Appearance pink blue white
Pulse >100 <100 none
Grimace cough Grimace none
Activity Normal Some None
Respiration strong weak none
Normal 7-10 Mildly depressed 4-6 Severely depressed 0-3

Question 11

CNS disorders in the term neonate

Answer 11

Hypoxic ischaemic encephalopathy (HIE)
Physical birth trauma
Meningitis
Fits/epilepsy
Inherited Neuromuscular disorders

Question 12

Hypoxic ischaemic encephalopathy - cause

Answer 12

Develops 2ary to perinatal fetal hypoxia due to placenta problems +- birth –> occurs in 6/1000 live births
Causes fetal distress –> decreased fetal movements, meconium staining, fetal acidosis leading to CNS depression +- permenant damage

Question 13

Neurological injuries from Physical birth trauma

Answer 13

Facial nerve palsy - pressure from maternal pelvis or forceps
Erb’s (C5/6) or Klumpke’s (C8T1) brachial plexus palsies
Fractures of clavicle, femur or humerus
Caput, cephalhaematoma or subaponeurotic haemorrhage
Intracranial haemorrhage - subdural, subarachnoid or parenchymal

Question 14

Fits/epilepsy in neonates

Answer 14

Subtle seizures can be common – hard to identify and poorly localized - grand mal –> treat with clonazepam if persistent
Any number of causes

Question 15

Hypoxic ischaemic encephalopathy - severity

Answer 15

Mild - irritable for 1-2days but not further problems
Moderate - abnormalities last for days to wks with risk of fits and 1/4 chance of neurodevelopmental problems
Severe - unconscious, poor resp effort, severe fits – always have some long term deficits - can also have liver/renal failure, DIC, NEC and pulmonary HTN

Question 16

Inherited neuromuscular disorders (MMMHI)

Answer 16

Myasthenia
Myopathies
Myotonic dystrophy
Hypotonias
IEM (inborn errors of metabolism)

Question 17

Neonatal hypoglycaemia

Answer 17

BM lower than 2.6mmol/L – if severe, persistent and symptomatic it will lead to CNS damage
Symptoms: lethargy, poor feeding, jittery, fits and comas, bradycardia, hypotension

Question 18

Causes of neonatal hypoglycaemia

Answer 18

Poor stores or increased demand - IUGR, postmature, sepsis, HIE, Polycythaemia, IEM
Hyperinsulinaemia - Diabetic mother, rare syndromes, abnormalities of insulin stimulation and release

Question 19

Management of Neonatal diabetes

Answer 19

Glucose stick measurement – with lab to confirm
Early feeds – if glucose <2mmol/L give 10% glucose IV bolus
If persistent exclude rarer causes

Question 20

Bilirubin metabolism

Answer 20

80% from Hb breakdown which is conjugated by the liver and secreted as bile – some of which is then reabsorbed
In blood 90% unconjugated bound to albumin & 10% conjugated

Question 21

Why is bilirubin high in neonates?

Answer 21

High Hb (14-19g/dL) with a shorter RBC half life
reduced activity of glucuronyl transferase
Increased gut circulation with decreased motility (stasis)

Question 22

Physiological neonatal jaudice

Answer 22

Occurs 1-2 days after birth and reaches the peak at 4-5days
Should always be <250umol/L and will resolve by 10days
visible in 60% of term babies

Question 23

Dangers of neonatal jaudice

Answer 23

Unconjugated bilirubin crosses the BBB causing neuronal damage in the basal ganglia, 8th nerve and cortex
Toxic at 450-500umol/L if health or 350umol/L if sick
At lower levels changes are reversible (sleepiness) but higher levels lead to sensorineural deafness
V. high levels cause Kernicterus

Question 24

Kernicterus

Answer 24

Bilirubin induced brain dysfunction
lethargy and poor feeding – hypertonicity and fits
50% will die and survivors develop choreoathetotic cerebral palsy, deafness and learning disabilities

Question 25

Causes of Early neonatal jaudice

Answer 25

Early (48hrs) -- as above + bacterial infections, polycythaemia, sequestered blood or IEM

Question 26

Causes of prolonged (>2wks) neonatal jaudice (4,4)

Answer 26

Unconjugated --> haemolysis as with early, hypothyroidism, breast milk jaudice, or rare causes Conjugated --> Hepatitis (infective or idiopathic) biliary atresia (intra- or extra- hepatic band, holedochal cyst or tumour), a1-antitripsin deficiency or CF

Question 27

Treatment of extra-hepatic biliary atresia

Answer 27

operation -- kasai portoenterostomy by 6 weeks to perserve function

Question 28

Treatment of Neonatal jaundice

Answer 28

Good hydration and feeding - bilirubin monitoring Phototherapy --> blue light isomerises bilirubin so it is excreted in urine Otherwise can give exchange transfusions of 2 x 80ml x kg

Question 29

Treatment of rhesus disease

Answer 29

Prevent development by giving mother anti-D in first pregnancy If it has happened treat with intrauterine transfusions (cord or intraperitoneal)

Question 30

Why are babies at risk of sepsis?

Answer 30

Low neutrophils and complement - only have maternal IgG

Question 31

Symptoms of sepsis in neonates?

Answer 31

Lethargy, poor feeding and vomiting -- may develop ileus and apnoea Can become hypoglycaemic, neutrophilic or neutropenic, thrombocytopaenic or DIC

Question 32

Sources of neonatal sepsis

Answer 32

Intrauterine or congential (present <48hrs) - group B strep is present in 15% of mothers, E.coli or staph aureus, gonococcus, chlamydia, listeria, candida If after 48hrs then likely acquired.

Question 33

Treatment of neonatal sepsis

Answer 33

Always investigate to identify source and causative organism | For broad cover give penicillin and gentamicin - if organism known give specific abx

Question 34

Signs of respiratory distress in neonates

Answer 34

Tachypnoea = RR>60, grunting, using the alae nasi, intercostal and subcostal recession, cyanosis Check the O2 stat and PO2/PCO2

Question 35

Causes of respiratory distress in neonates (8)

Answer 35

Transient tachypnoea of the newborn, RDS due to surfactant deficiency in preterm of IDM babies, Pneumothorax, meconium aspiration, pulmonary HTN, Heart failure, acidosis, congential abnormalities (diaphragmatic hernia)

Question 36

Transient tachypnoea of the newborn

Answer 36

slow removal of lung liquid after a CS

Question 37

Cardiac disease in neonates

Answer 37

structural problems will present as cyanosis or heart failure May have arrhythmias Murmurs in the neonatal period are common -- PDA, VSD or functional (most common)

Question 38

Gastrointestinal abnormalities in neonates

Answer 38

Obstructions - oesophageal or intestinal atresia, tracheo-oesophageal fistula, Meconium ilieus or hernias, hirschspung's disease, imperforate anus Necrotising enterocolitis - preterm babies or those exposed to hypoxia Exomphalos or gastroschisis

Question 39

Symptoms of GI obstruction in neonates

Answer 39

High - early vomiting without abdominal distension. no bile if before ampulla of vater Low - failure to pass meconium within 24hrs and abdominal distension precedes vomiting.

Question 40

Genitourinary problems in neonates

Answer 40

Should pass urine by 24hrs --> if not screen for structural abnormalities Vaginal bleeding/discharge is normal due to withdrawal of maternal hormones

Question 41

Kidney and bladder problems in neonates

Answer 41

UTI in males should be investigated for congenital abnormalities Renal pelvic dilation could be physiological but requires follow up Posterior urethral valves and vesicoureteric reflux should be assessed and managed (operatively or conservatively)

Question 42

Genital abnormalities in neonates

Answer 42

Hypospadias (misplaced urethral opening) Ambiguous genitals should be assessed and action taken immediately Undescended testes should be operated on before 1yr

Question 43

Milia

Answer 43

pearls of keritin which appear on the skin, particularly on the face and may be itchy -- they are almost entirely benign They can occur in the mucosa (epstein's pearls) or palate (bohn's nodules). in the elderly they should be biopsied to exclude Favre-Racouchot syndrome

Question 44

Miliaria

Answer 44

Sweat rash caused by dysfunction of sweat glands, more common in children - crystalline is most common, rubra is painful and profunda is most severe

Question 45

Heel prick test

Answer 45

Taken on day five ideally - checks for PKU, congenital hypothyroidism, sickle cell, CF and MCAD deficiency

Question 46

Breast milk jaundice

Answer 46

Late onset jaundice from the first to sixth weeks of life in a healthy breast fed baby -- thought to be caused by hormone metabolites in the breast milk which block conjugation of bilirubin

Question 47

Breastfeeding jaundice

Answer 47

Early onset jaudice in primigravid mothers where there is inadequate early hydration due to poor milk production leading to jaundice

Question 48

Group B neonatal sepsis

Answer 48

Biggest cause of sepsis as 15% of mother carry and most babies are colonised but not infected -- causes respiratory distress in first 24hrs Can lead to multi-organ failure --> very sensitive to penicillin and should treat aggressively

Question 49

Sudden infant death syndrome

Answer 49

Commonest cause of death of children in the first year of life (after this is accidents) Peaks at 3months of age. RFs: prematurity, smoking, phyerthermia, sleeping prone, male, multiple birth, bottle fed, Maternal drug use, winter, low social class

Question 50

Management of meconium ilieus

Answer 50

Gastrograffin enema is both diagnostic and theraputic. surgical decompression can be used.