Neonate Flashcards
ROP
Screening - <30 weeks - < 1250g
Other RF: TTTS, PPHN ON NO, grade 3/4 IVH, hydrops, severe sepsis
Plus disease - tortuousity of retinal vessels
Treatment
Zone 1 - any stage with plus; stage 3 w/o plus
zone 2- stage 2/3 with plus
LEOPARD Syndrome (noonan with multiple lentigenes)
Lentigenes (multiple brown black spots) ECG conduction Ocular hypertelorism Pulmonary stenosis Abnormal genitals Retarded growth (short stature) Deafness or inner ear malfunction Mutation PTPN11 mutation, AD you inheritance
HIE Cooling
Aim to decrease apoptosis and reduce glutamate/lactate/NO/free radicals causing damage
- Ideal within 6 hours
- Reduce core temp 33.5
- Whole body best
- For 72 hours
Reduced mortality and improves outcome at 18/12
Seizures managed with phenobarb
Prognosis: Ph < 6.7 90% death or severe impairment
Other High risk, low Apgar 5 mins Base deficit >22, decerebrate posture, seizures beyond 72hrs, severe lesions on imaging
Omphalocoele
60% associated other anomalies CHD BWS BWS Foetal overgrowth syndrome Imprinting defect Ch11 (IGF2 gene) Macroglossia Abdominal wall defect Hypoglycemia (hyperinsulinism) Ear lobe creases Hemi hypertrophy Facial nevus flammeus
Fetal NAIT Fetal platelets have antigens inherited from father, that not present on mum, maternal immune system recognised it as foreign and mounts immune response
Often occurs first pregnancy 2 most common antigens are 1. HPA 1a 2. HPA 5a Low platelets, risk bleeding, rare ICH ROLE IVIG, platelet transfusion
Fetal alcohol syndrome
IUGR Facial features - short palpebral fissures, epicanthic folds, smooth philtrum, thin upper lip Cardiac defects - ASD OR VSD Limb anomalies Developmental delay / ID
Infant diabetic mother’s Maternal hyperglycaemia causes fetal hyperglycaemia which causes fetal hyperinsulinism
Hypoglycemia Hyperinsulinism - LGA - cardiomyopathy (HOCM) - birth asphyxia - surfactant deficiency : RDS Mortality 5x increase INCREAsed risk still birth chromosomal abnormalities (3x risk) Fetal hypoxia and elevated haematocrit Jaundice Diazoxide for hyperinsulinism - Opens K ATP channel, beta cells pancreas, inhibits insulin release from pancreas SE sodium and water retention
HFOV Improve ventilation by
Decreasing frequency Increasing amplitude Improve oxygenation (increase MAP)
Tidal volume
4-7 ml/kg
Increase MAP
Increase PIP Increase PEEP (May increase CO2) Increase Ti / reduce Te
Oxygenation increase
Fio2 Map
Minute ventilation
VT X rr (200-300ml/kg)
Infantile Haemangiomas
1-3% newborns ; 3:1 Female to male
Preterm 30%, LBW 25%
Present at 2 weeks usually, rapid growth in first year (80%growth by 6/12), stabilise and involute from 12months (3-10years gone by)
GLUT1+ve
PHACES (9:1 F:M) - screen if segmental IH of head >5x5cm or if other anomalies
Alternative types: -RICH(rapid involute) -NICH(non involute)
- older, glut1-ve, non response propranolol
Rx propranolol if needed SE
PHACES
9:1 F:M screen if segmental IH of head >5x5cm or if other anomalies - Posterior fossa ; - Haemangioma (segmental IH of face) - Arterial anomalies (AV malform, cerebral infarct) - Cardiac - Endocrine anomaly - thyroid, pituitary ; Eye abnormal Risk stroke, airway obstruction, SNHL, dysphagia, endocrine Rx Propranolol
Audiology tests and ages
Birth - ABR
Visual reinforcement test 6-12mo
Play audiometry 2-4 years
Pure tone audiometry 4 years
Tympanometry only measures middle ear pressures
Prelingual hearing loss
20% environmental
80% genetic
- Syndromic 20%
- Non syndromic 80%
80%recessive, 20% dominant
Connexin26 (GJB2 mutation most common non syndromic genetic cause
Syndromic hearing loss
- Goldenhar (Oculo-Auricular-Vertenral syndrome) - Hemifacial microsomia, spinal problems, cardiac, hearing loss (SNHL + CHL)
- Wardenburg - AD, 1:40,000, hearing loss from birth, SNHL ; white forelock, iris heterochromia
- Brachio-Oto-Renal - AD, Branchial cleft anomalies, Ear problems-pits, hearing loss ; renal dysplasia (60%)
- PENDRED -AR severe profound SNHL and goitre with normal TFTs(7% CHL)
- NF
- CHARGE
- Treacher collins
- Ushers
Tympanograms
A - Normal
B - Flat - OME, Cholesteatoma, Otosclerosis
C- high negative pressure w/o effusion (Eustachian tube dysfunction)
Subgaleal bleed
Occurs 1/200 vacuum delivery (1/2000 NVD) RF - 3+ pulls, >20mins effort, cup comes off ; contraindicated to do vacuum under 36weeks Fluctuating mass. Diffuse, crosses suture lines Can cause shock, can lose up 20-40% circulating volume Baby has 80ml/kg circulating volume 35ml blood needed to increase HC by 1 cm
Craniosynostosis
Craniosynostosis is premature closure of the cranial sutures, and is associated with varying skull shapes. ◾Primary craniosynostosis results from closure of one or more sutures owing to abnormalities of skull development. ◾Secondary craniosynostosis results from failure of brain growth and expansion. Primary craniosynostosis: ◾Occurs 1:2000 births. ◾Cause is unknown in the majority. ◾Deformational forces are important in occipital and frontal plagiocephaly. ◾Early detection of posterior skull shape is critical to allow successful intervention (e.g. physical therapy for torticollis.) Sagittal craniosynostosis: ◾Most common CSO affecting a single suture ◾~80% male ◾Results in scaphocepahly (boat-shaped head) ◾Frontal bossing, prominent occiput, normal occipto-frontal circumference, reduced biparietal diameter, small or absent anterior fontanelle ◾Nil hydrocephalus/normal ICP/normal neurology Metopic craniosynostosis: ◾Association with 19p chromosome abnormality ◾Results in trigoncephaly ◾Pointed forehead and midline ridge, hypertelorism Coronal Craniosynostosis: ◾18% of craniosynostosis ◾More common in females ◾Associated with Apert syndrome (with syndactyly) and Crouzon disease (with hypoplasia of the midface) ◾Unilateral - plagiocepahly, bilateral - brachycephaly, acrocephaly ◾Elevation of the eye socket, flattening of the ridge of the eye and displacement of the nose on the affected side, flat cheeks Lamboid craniosynostosis: ◾10-20% ◾More common in males ◾Right side affected in 70% cases ◾Flattening of occiput, bulging of ipsilateral forehead, ipsilateral ear is anterior and inferior Multiple craniosynostosis ◾Oxycephaly - tower skull with undeveloped sinuses and shallow orbits, elevated ICP Treatment: ◾Most cases are evident at birth as a result of premature suture fusion ◾Palpation of the suture reveals a prominent bony ridge ◾Fusion of the suture can be confirmed on skull x-ray ◾Premature fusion of only one suture rarely causes a neurological deficit ◾Sole indication for surgery is the child’s cosmetic appearance - prognosis depends on the suture involved and the degree of disfigurement ◾In general craniosynostosis can be surgically corrected with good outcomes and relatively low morbidity and mortality, especially for non-syndromic infants
Lung embryology
There are four stages of in utero lung development.
• Embryonic – up to 5 weeks
Pseudoglandular – weeks 6 – 16.
• Airways grow via branching out to terminal bronchioles
Canalicular – weeks 17 – 24.
- More conventional architecture of lungs with initial development of alveolar acini, thinning out of distal cells, development of arterial and venous circulation.
- Fluid in lungs.
- Surfactant first starts to be produced.
Saccular stage – weeks 24 – 40.
• Respiratory bronchioles, alveolar ducts, alveoli develop and cells differentiate into type 1 (gas exchange) and type 2 (make surfactant) pneumocytes.
Alveolar stage – 36 weeks gestation until 24 months postnatal.
- Further alveolar formation and maturation, secondary alveolar septa, cell proliferation and maturation.
- 20-50 million alveoli by birth, 300 million alveoli by adulthood.
Development of lung contributed to by
- Fetal / neonatal growth (nutrition)
- Antenatal steroid exposure,
- Transcription and growth factors,
- Sufficient lung fluid,
- Muscle tone and fetal breathing,
- Toxicity (e.g. from oxygen, barotrauma, infection/ inflammation)
Craniosynostosis 2
Scaphocephaly – fusion of sagittal suture, resulting in elongation of anteroposterior axis of cranium. • It accounts for 50% of craniosynostosis cases, at a rate of 1 in 2000
Trigonocephaly – premature closure of metopic suture, resulting in a triangular shaped forehead. • It accounts for 10% of craniosynostosis cases
Plagiocephaly – premature closure of unilateral coronal or lambdoid sutures, resulting in a asymmetric or twisted skull. Incidence of 1 in 10,000. • Not to be confused with positional plagiocephaly
Acrocephaly – premature closure of combined sagittal, coronal and lambdoid sutures, resulting in elevation of anterior cranium. • Seen in Crouzon or Apert syndromes
Survival in preterm 23/40, 24, 25, 27, >30
23: 15% 24: 66% 25: 80% 27: 90-95% 30: 97-99%
Severe neurological disability ELBW
10-20%
Risks of maternal diabetes for neonate
- 3 x inc congenital malformations (CHD, sacral agenesis, NTD, microcolon) - SGA (due to small vessel disease) or LGA (hyperglycaemia) - Hypoglycaemia, low Ca + Mg - Surfactant deficiency, polycythaemia, jaundice, transient septal hypertrophic cardiomyopathy
HFOV under ventilated and under oxygenated change what settings
To improve ventilation (increase amplitude and then decrease Hz) AF To improve oxygenation (increase MAP)
Most common type oesophageal atresia
Type C - oesophageal atresia with a distal TOF (85% of cases)
Hearing screen NZ and Aus use
Automated auditory brainstem response (aABR
Antigen in neonatal alloimmune thrombocytopenia
Human platelet antigens (HPA-1a)
Fetal haematopoeisis
Yolk sac from 2weeks – 2 months; liver 2-7 months; bone marrow starts at 3 months and predominates from 7th month
Which drug exposure in utero causes broad low nasal bridge epicanthal folds, wide spaced eyes, microcephaly, cleft lip and palate with hypoplasia distal phalanges
Fetal hydantoin syndrome from phenytoin
What factors are required to calculate the oxygenation index (OI)?
[FiO2 (%) x Mean airway pressure (mmHg)] / PaO2 (mmHg) Oxygenation index is useful for objectifying the intensity of ventilation required and the severity of hypoxaemia. >25 is “high” and correlates with severe type 1 respiratory failure, ECMO required
Persistent pulmonary hypertension of the newborn (PPHN)
- Tachypnoea, possible pansystolic murmur (tricuspid regurg), prominent 2nd heart sound - If significant then >10% pre and post ductal sats discrepancy (pre>post) resulting from R-L shunting via the ductus - Often idiopathic, but can be due to sepsis, birth asphyxia meconium aspiration, pulmonary hypoplasia, and maternal medications (SSRI+NSAIDs)
What proportion of cleft lip and palates are not associated with a syndrome (i.e. non-syndromic)?
70% (in contrast, 50% of isolated cleft palate are not associated with a syndrome, and 90% of isolated cleft lips) Syndrome with cleft palate - Stickler syndrome - 22q11 deletion - Treacher-Collins syndrome
Describe neonatal lupus
- Symptoms: congenital heart block, cutaneous lesions after UV exposure, hepatitis, thrombocytopenia, neutropenia, pulmonary and neurological disease
- Maternal transfer of SLE IgG autoantibodies, usually anti Ro/SSA or anti La/SSB, between 12-16/40
- Most manifestations resolve, apart from heart block (can use AN and PN steroids)
Recurrence risk future pregnancies approx 20%
What develops from the endoderm?
- Internal layer - Alveolar/lung cells, thyroid, GI, pancreas
What develops from the mesoderm?
- Middle layer - Cardiac, smooth muscle cells (gut), skeletal muscle, RBC/circulatory system, tubules of kidney
What develops from the ectoderm?
- Outer layer - Skin, pigment cells, central nervous system
Describe the process of gut formation in the fetus?
- Extra-abdominal gut rotates 270 degrees anticlockwise around the mesentery (containing SMA) - Failure to complete this results in malrotation and risk of volvulus - Gut returns to abdomen at 12/40. Errors in this result in gastroschisis and exomphalos
Describe the process of neural tube development
- Neural tube forms by 3/40 - Neural groove closes in cranial to caudal direction at end of 4/40 - Myelination of Schwann cells begins at 12/40, increases from 24/40, not complete until age 2
Describe the process of gonadal development
- Y chromosome (SRY gene) influences the development of the gonads after 6/40 - Testes secrete Mullerian inhibiting factor which results in regression of the uterus/vagina/fallopian tubes - Testosterone influences development of Wolfian structures (prostate, seminiferous tubules, vas deferens)
Risks of hypertension/pre-eclampsia for neonate
- SGA - Polycythaemia - Neutropenia, thrombocytopenia - Hypoglycaemia
Risks of maternal thyroid disease for neonate
- Maternal Grave’s causing thyrotoxicosis - Neonatal hypothyroidism due to maternal anti-thyroid medications
Describe neonatal thyrotoxicosis
- Due to transplacental passage of thyroid-stimulating antibodies from mother with Grave’s disease - Rare, only 1/70 mothers with thyrotoxicosis - Can cause goitre, low birth weight, failure to gain weight, tachycardia, restlessness, jitteriness - Check cord TSH + TSH/T4 at 10-14 days age - Severe cases treat with beta-blocker and carbimazole - Self resolves as antibody levels fall
Neonatal thrombocytopenia
- Autoimmune: maternal ITP, mother also has low platelets. If <50 treat IVIG and plt transfusion due to risk ICH. Can’t use Mum’s platelets - Alloimmune: NAIT, maternal antibodies against father’s platelet antigen, IgG antibodies cross placenta. Risk ICH, treatment IVIG, irradiated maternal platelets/random donor
Risk of maternal myasthenia gravis on neonate
- 10% risk - transplacental passage of ACh receptor antibodies - Weakness, poor suck, resp distress, ptosis - Maternal severity doesn’t correlate with baby’s severity - Diagnosis via antibody assay, EMG, neostigmine test - Usually presents early, resolves by 2 months of age. May require physio if contractures - If antibodies absent or symptoms persist then consider congenital myasthenia gravis (AR)
Describe the features of foetal alcohol syndrome
- SGA, IUGR, postnatal growth failure - Microcephaly, CHD - Facies: long and smooth philtrum, thin upper lip, micrognathia, ear abnormalities, flat nasal bridge, epicanthic folds, short palpebral fissures - Intellectual impairment
Describe neonatal abstinence syndrome
- Within 1-2 days, but up to 7-10 days age - Persists longer with methadone - Wakefulness, irritability, jitteriness, sneezing, apnoea, tachypnoea, diarrhoea, weight loss, seizures, high pitched cry - Inc risk SIDS, decr risk surfactant deficiency - <50% require treatment. Tx PO morphine
Teratogenic effects of sodium valproate?
Neural tube defects, fused metopic suture, mid-face hypoplasia, CHD, hypospadius, talipes, GDD, finger/toe abnormalities
Teratogenic effects of isotretinoin and high dose Vit A?
Cleft palate, hydrocephalus, CHD
Small salmon pink papules and sepsis is likely due to which organism?
Listeria monocytogenes infection - not susceptible to cephalosporins (GBS and E. coli are most common cause early-onset sepsis, responsible for 60–70% of cases).
Discuss the circulatory changes that occur after delivery
- Expansion of the lungs + inc arterial PO2 causes rapid decrease in pulmonary vascular resistance - Removal of low-resistance placental circulation causes inc systemic vascular resistance - Output from RV flows entirely into the pulmonary circulation and shunt through ductus reverses L-R (pulm resistance < systemic resistance) - High arterial PO2 constricts ductus arteriosus - Inc volume of pulmonary blood flow returning to the left atrium causes inc LA pressure > RA pressure, functionally closing flap of foramen ovale
What keeps the ductus open during fetal life?
Prostaglandin E2 + I2 (prostacyclin) (note: use prostaglandin E1 infusion to keep ductus open post-natally)
How does nitric oxide work?
In vascular smooth muscle nitric oxide causes inc intracellular cGMP. This leads to smooth muscle relaxation and vasodilation by stimulating cGMP-dependant protein kinase which reduces intracellular calcium
How do you calculate the perinatal mortality rate?
Death from 20/40 to 6 days/ per 1000 live and stillbirths
How do you calculate the neonatal mortality rate?
Death of liveborn infants <28 days old/ per 1000 live births
What are the early and late complications of IUGR?
- Early: hypothermia, hypoglycaemia, hypoxia, HIE, polycythaemia, neutropenia, thrombocytopenia, NEC - Late: metabolic syndrome, HTN, diabetes, increased neurodevelopmental issues, short stature (if severe IUGR)
What are the causes of SGA?
- Maternal - smoking, diabetes, HTN, PET, lupus, altitude
- Placental - insufficiency
- Neonatal - multiple gestation, infection, congenital malformations
Role of T1 and T2 pneumocytes
- T1 pneumocytes responsible for gas exchange - T2 pneumocytes produce surfactant after 26/40, line 5-10% of alveolar surfaces
What is the role of surfactant, and what is it made of?
- Lowers surface tension at the air-alveolar interface, preventing end-expiratory alveolar collapse, stimulates lung-host defence mechanisms
- Made of phospholipids (85%), other lipids (10%, help with immune function and absorption) and platelet-activating factor (increases surfactant secretion)
- Decreased Surfactant: prematurity, males, sepsis, diabetes, 2nd twin, elec C/S, FHx
- Increased surfactant: females, PROM, maternal opiate use, IUGR, AN steroids
What are the benefits of maternal antenatal steroids?
- Decrease in: mortality (by 31%), IVH (by 46%), NEC, RDS, requirement for resp support, NICU admission, early onset sepsis - Give if likely preterm birth 24-34+6/40, also elec C/S up to 38+6/40 - Repeated doses after 7 days. No benefit after 34+6/40
What are the benefits of exogenous surfactant administration?
- Decreased mortality, pneumothoraces, and possibly CLD. - No effect on IVH - Give early to those who need it - early but selective (FiO2 >30% and worsening, 200mg/kg for initial dose) - Benefit with multiple doses
Describe CLD/BPD
- Requirement for resp support >28d or >36/40 - Risk factors: prem, prolonged I+V, barotrauma, O2 toxicity, pneumothoraces, GOR, PIE, PDA, chorioamnionitis, infection (esp CMV) - Only a few require home O2, weaned by age 1-2y - Inc risk infection and hospitalisation - Usually normal exercise tolerance in childhood - No treatment. Good nutrition important
Describe risks and treatment for meconium aspiration
- RFs: term or post-term, SGA, perinatal asphyxia - Leads to airway blockage (inc airway resistance, gas trapping, pneumo), chemical pneumonitis, infection (E.Coli), surfactant deficiency/PPHN (lipid content of meconium displaces surfactant from alveolar surface) - Tx: resp support, surfactant replacement shows benefit but require large doses, ECMO if severe
Ventilator adjustments to decrease risk of pneumothroaces
Volume guarantee, lower ventilation pressures, faster rate ventilation with short iTime, surfactant, paralysis of infants fighting ventilator
Describe pulmonary interstitial emphysema (PIE)
Up to 25% of VLBW infants - Rupture of overdistended alveoli causes cysts in pulmonary interstitium - Increased risk if chorioamnionitis - Ventilation is difficult - Increased risk of CLD and mortality