Neonates Flashcards
At what age is newborn screening (heel prick/guthre test) carried out?
Day 5-7
What conditions are screened for in the UK on the newborn heel prick?
Sickle cell disease Cystic fibrosis Congential hypothyroidism AND 6 inborn errors of metabolism: 1. Phenylketonuria (PKU) 2. Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) 3. Maple syrup urine disease (MSUD) 4. Isovaleric acidaemia (IVA) 5. Glutaric aciduria type 1 (GA1)
- Homocystinuria (pyridoxine unresponsive) (HCU)
Why is neonatal jaundice so common?
Because in the fetus there is a higher concentration of Hb (to maximise O2 exchange).
After delivery there is breakdown of Hb as the raised concentration is no longer needed.
ALSO the liver is immature and is unable to process high Hb concentrations.
What is kernicterus?
Encephalopathy resulting from deposition of unconjugated bilirubin in the basal ganglia and brainstem nuclei.
It can occur when the levels of unconjugated bilirubin exceeds the albumin-binding capacity of bilirubin the blood. The free bilirubin is fat soluble so can cross the blood brain barrier.
What are the neurotoxic effects of kernicterus?
They can vary in severity from acute manifestations - lethargy and poor feeding.
Severe cases - irritability, increased muscle tone causing the baby to lie with an arched back, seizures and coma.
Infants who survive may develop choreoathetoid cerebral palsy (damage to basal ganglia), learning difficulties and sensorineural deafness.
WHO recommends exclusive breast feeding for how long?
6 months
Breast feeding reduces the risk of which conditions in later life? (think cardiovascular type)
Insulin-dependent diabetes
Hypertension
Obesity in later life
What are the benefits of breast feeding with regards to gastro problems?
Reduces risk of gastroenteritis and necrotising enterocolitis (in premature infants)
As well as gastroenteritis breast feeding also reduces the risk of which types of infections?
Otitis media
Respiratory infections
What are the benefits to the mother of breast feeding?
Reduced risk of:
Type 2 diabetes
Ovarian cancer
Breast cancer
In what situations is breast feeding contraindicated?
Chemotherapy (cytotoxic drugs)
HIV
With breast feeding the volume of milk intake is not always known so how can you monitor growth?
Monitor weight gain
How does colostrum differ from milk?
Colostrum is produced for the first few days
Colostrum differs from mature milk in that the content of protein and immunoglobulin (IgA, IgM and IgG) is much higher
What is the histology of breast lobes?
Which 2 hormones are important in milk secretion? Describe each of their roles
Breast tissue lobes are make up of lobules of alveoli, blood vessels and lactiferous ducts. The lactiferous ducts connect the lobules to the tip of the nipple (areola). Myoepithelial cells surround the alveoli and are responsible for milk let down.
PROLACTIN secretion stimulates milk secretion by cuboidal cells in the acini of the breast. It is produced from the anterior pituitary.
OXYTOCIN secretion results in contraction of myoepithelial cells in the alveoli, forcing milk into larger ducts - the so-called ‘let-down’ reflex
Why is unmodified cow’s milk unsuitable for feeding an infant? What can is subsequently result in?
Because it contains a protein called casein. The baby can’t digest this. It can lead to diarrhoea
What is WHO’s code of marketing breast milk substitutes?
What additional modifications are made to formula feeds?
-
The code prohibits advertising of infant formula, bottles and teats and gifts to mothers or inducements to health workers.
Formula fees make their mineral content and renal solute load comparable with that of mature human milk.
They also have polyunsaturated fatty acids, nucleotides, prebiotics and probiotics
What is the advice given with regards to children who are on cow’s milk? (E.g what age/what type)
Should receive full fat milk up to the age of 5 years
After what age does breast milk become increasingly nutritionally inadequate as the sole feed for infants?
When should solid foor be introduced:
A) Not before?
B) No later than?
After 6 months of age, breast milk becomes increasingly nutritionally inadequate as a sole feed, as it does not provide sufficient energy, vitamins or iron.
Solid foods are recommended to be introduced from around 6 months of age, not before 17 weeks and no later than 26 weeks
How do the components of milk change over the first 2 weeks?
What types of food should infants initially be weaned onto?
The milk develops to contain less proteins, more fat and more sugars (energy source)
Weaning should be done gradually, initially with small quantities of pureed fruit, root vegetables or rice.
In women who are pregnant where is group B streptococci commonly present?
What percentage of pregnant women carry group B strep?
Vagina or rectum
25% of women
What can group B strep cause in neonates?
Infection - typically sepsis, pneumonia or meningitis
This is known as early onset GBS disease of the newborn
What is considered to be early-onset neonatal sepsis?
How does early-onset sepsis present?
What are the most likely causative organisms of early-onset sepsis?
Sepsis that presents within 48 hours of birth
Presents with:
It is associated with acquisition of micro-organisms from the mothers birth canal (e.g group B strep)
What is considered to be late-onset neonatal sepsis?
How does late-onset sepsis present?
What are the most likely causative organisms of late-onset sepsis?
Why do they present later?
Late onset = >48 hours from birth
Late-onset sepsis normally occurs due to hospital acquired pathogens such as Staphylococcus epidermidis and Staphylococcus aureus
A high percentage of women are colonised with group B strep but not as many have affected infants. What are some risk factors for infection in the neonate?
UTI caused by GBS during pregnancy Previous baby with GBS infection Pyrexia during labour Prematurity <37 weeks Positive GBS swab during pregnancy Rupture of membranes >24 hours before delivery
What types of swab is used to look for group B strep in pregnancy? What week is this done at?
One swab (the same swab) is used for the vagina and then the rectum
2 individual swabs can be used of preferred
Not all women are screened only if you are high risk.
It is carried out at 33-35 weeks if the woman was found to have GBS colonisation in a previous pregnancy but the fetus was not affected with GBS
What are antibiotics given for prophylaxis of early onset neonatal group B strep?
Who is given them?
High dose IV Penicillins e.g benzylpenicillin OR cefuroxime in pen allergic
Indicated in women who are high risk:
- GBS positive swabs
- A UTI caused by GBS during this pregnancy
- Previous baby with GBS infection.
- Pyrexia during labour
- Labour onset <37 weeks
- Rupture of membranes >18 hours
What is the difference between symmetrical growth restriction and asymmetrical growth restriction a) in terms of presentation? b) in terms of when the restriction occurs?
Asymmetrical:
Weight of abdominal circumference lies on the lower centile than that of the head
Failure of placenta to provide inadequate nutrition in later pregnancy
Symmetrical: head circumference is equally reduced as abdominal circumference. Suggestive of a prolonged period of poor intrauterine growth starting in early pregnancy
What are some underlying causes of asymmetrical growth restriction?
Uteroplacental dysfunction secondary to maternal pre-eclampsia, multiple pregnancies, maternal smoking or can be idiopathic
Infants rapidly put on weight after birth
Associated with an increased risk of obesity and type 2 diabetes in later life.
What are some causes of symmetrical growth restriction?
It is usually due to a small but normal fetus, but may be due to a fetal chromosomal disorder or syndrome, a congenital infection, maternal drug and alcohol abuse, a maternal chronic medical condition or malnutrition. These infants are more likely to remain small permanently.
Need to finish IUGR
Is cow’s milk protein intolerance/allergy seen more common in breast or bottle fed infants?
Formula fed (bottle fed). It is rarely seen in exclusively breast fed infants.
What are the features of cow’s milk protein intolerance/allergy?
Regurgitation/vomiting Diarrhoea Urticaria, atopic eczema 'Colic' symptoms: irritability, crying Wheeze, chronic cough Rarely angioedema and anaphylaxis occur
By what age does cow’s milk protein intolerance usually resolve by?
1-2 years
How are infants with cow’s milk protein intolerance managed is they are formula fed?
- Extensive hydrolysed formula (eHF) milk is the first line replacement formula for infants with mild-moderate symptoms
- Amino acid based formula in infants with severe CMPA or if no response to eHF
- Around 10% of infants are also intolerant to soya milk
How are infants managed if they HAVE cow’s milk protein intolerance and are breast fed?
Continue breastfeeding
Eliminate cow’s milk protein from maternal diet
Use extensive hydrolysed formula milk with breastfeeding stops, until 12 months of age and for at least 6 months
What is the APGAR score?
Activity Pulse Grimace (response to stimulation) Appearance (in terms of colour) Respiration
What is the most common cause of respiratory distress in TERM infants?
Transient tachypnoea of the newborn
What are some of the causes of pulmonary hypoplasia?
Oligohydramnios
Congenital diaphragmatic hernia
If a baby is delivered and there is a large mount of meconium during delivery what factors would prompt involvement of the neonatal team?
RESP: RR > 60/min Presence of grunting O2 sats <95% CARDIO: Cap refil >3 sec Presence of central cyanosis HR <100 or >160 Temp >38 or >37.5 or 2 occasions 30 minutes apart
What does NIPE stand for?
When is it carried out?
Newborn and infant physical examination
1st - within 72 hours
2nd - 6-8 weeks
Why should vitamin K be given to all newborn infants?
In order to prevent haemorrhagic disease of the newborn (vitamin K deficiency results in it).
How does vitamin K administration vary in women who are on anti-convulsants? Why?
Mothers on anticonvulsant therapy should receive oral prophylaxis from 36 weeks’ gestation and the baby should be given IM vitamin K.
Anticonvulsants impair the synthesis of vitamin K
What are some unconjugated causes of jaundice that presents <24 hours after birth?
Haemolytic disease of the newborn
ABO incompatibility
Sepsis
Red cell anomaly - spherocytosis, G6PDD
What are some causes of unconjugated jaundice >24 hours after birth?
Physiological
Breast milk jaundice
Hypothyroidism
Sepsis (congenital or post natal)
What are some causes of conjugated jaundice in neonates?
When do they usually present?
Bile duct obstruction
Neonatal hepatitis
Usually present at around 2 weeks
In some babies who are jaundiced and breast fed supplemental feeding is sometimes needed. Why is this?
Because in some infants the jaundice is exacerbated if milk intake is poor from a delay in establishing breast-feeding and the infant becomes dehydrated.
The supplemental feeding is needed to reverse the dehydration
In some infants IV fluids are needed to reverse the dehydration.
What is haemolytic disease of the newborn/rhesus disease?
It is when the mother is RHESUS D NEGATIVE and the baby is RHESUS D POSITIVE.
The mother is exposed to rhesus D positive blood in a previous pregnancy so produces anti-D IgG (e.g antibodies towards rhesus D).
If she has a pregnancy where the baby is RhD Positive her antibodies attack the babies blood and can result in anaemia, jaundice and other complications.
What is hydrops fetalis?
A severe, life threatening problem where the is swelling of the fetus
Accumulation if fluid in at least 2 fetal compartments
It is usually seen in the fetal subcutaneous tissue and can lead to spontaneous abortion.
It is a prenatal form of heart failure
What 4 things are being screened for in a NIPE?
Eyes
Testes
Hips
Heart
Is GBS screened for routinely?
Who is considered to be an high risk of GBS during pregnancy?
No, only people who are considered to be high risk are tested
High risk: Women with symptoms of - UTI - Chorioamnionitis - Those with STI symptoms pre pregnancy - women with a previous GBS infected baby
What is chorioamnionitis?
It is also known as intra-amniotic infection (IAI) and is an inflammation of the fetal membranes (amnion and chorion) due to a bacterial infection
What are the 3 main ways that GBS can manifest in a pregnant woman?
How may each of these present?
- UTI: frequency, urgency, dysuria
- Chorioamnionitis: fevers, lower abdo/uterine tenderness, foul discharge, maternal and/or fetal tachycardia
- Endometritis: fevers, lower abdo pain, intermenstrual bleeding, foul discharge (occurs pospartum)
Why is it not advised to screen routinely for GBS?
Because the majority of babies affected are preterm and they would be likely to be missed because they would be likely to have to delivered by the screening date
Not all women who screen positive GBS during their pregnancy are positive at birth so these women would be treated uneccesariliy
What are some risk factors for a baby getting group B strep?
Prematurity
Prolonged rupture of membranes
Previous sibling with GBS infection
Maternal pyrexia e.g secondary to chorioamnionitis
What are the 2 main types of active management of jaundice?
Phototherapy
Exchange transfusion
When is phototherapy stopped?
How do you follow uP
When the bilirubin is >50 below the threshold graph.
You must check for rebound hyperbilirubinaemia 12-18 hours followings stopping
What is considered to be prolonged jaundice?
What things should you consider?
If the jaundice is not fading by 14 days in term babies or by 21 days in prem babies
You should consider:
- Sepsis
- Metabolic - cong hypothyroidism/pituitarism, galactosaemia
- Breast milk jaundice - resolves between 1.5-4 months
- GI - biliary atresia, choledhocal cyst
What investigations should be carried out on a baby with jaundice?
There are specific further investgations you may consider carrying out - what are they and when would you carry them out?
- First = transcutaneous bilirubinometer
- Then serum bilirubin
- Total and conj/unconj bilirubin
- Blood group (mother and baby), DCT
- FBC for Hb and haemocrit
Further….
- U&Es if XS weight loss/dehydrated
- LFTs is suspected hepatobiliary disorder
- FBCs for Hb and haemocrit
What is considered a pre-term infant?
Delivery <37 weeks
What are some of the causes of premature delivery?
- Planned due to life threatening conditions affecting either the mother or fetus (pre-eclampsia, renal disease, severe growth restriction)
- PPROM/PROM
- Emergency e.g eclampsia/severe infection/placental abruption
- 40% have no identifiable cause
What are some risk factors of premature delivery?
Previous preterm delivery
Multiple pregnancy
Smoking and illicit drug use in pregnancy
Being under or overweight in pregnancy
Early Pregnancy (within 6 months of previous pregnancy)
Problems involving cervix, uterus or placenta, including infection
Certain chronic conditions such as diabetes and hypertension
Physical injury/trauma
Following stabilisation and transfer to the neonatal unit there are several baseline obs most prem infants require - what are some?
- Blood gas (to assess metab and resp state and alter support)
- FBC - infection, thrombocytopaenia and anaemia
- U&Es aren’t usually performed at initial admission as it’s more likely to be reflective of the mother’s electrolyte balance
- Blood culture (increased risk of infection) - most are started on IV Abx
- CRP - infection
- Blood group and DCT - many require blood transfusion and evelop jaundice.
What imaging/invasive tests should be performed on premature babies following admission to the neonatal unit? Why?
CXR - most <32 require resp support. To look for site of endotracheal tube and look for pneumothoraxes
AXR - ook for central venous access in umbilical vein and arteries for PRN, also to look for NEC
CrUSS - for infants born at <32 weeks - assess for any signs of intraventricular haemorrhage
What have antenatal steroids shown to reduce the risk of in neonates?
RDS and IVH
What is the approach towards resuscitation of premature neonates?
<23 weeks - resus should not be performed
23 and 23+6 weeks - may be decision NOT to start resuscitation, especially if parents have expressed this wish
24-24+6 - resus should be commenced unless the baby is thought to be severely compromised
>25 weeks - it is appropriate to resuscitate and start intensive care
What problems may a pre-term neonate have with regards to their respiratory system?
How may this be managed?
RDS Surfactant deficient lung disease Chronic lung disease Bronchopulmonary dysplasia Recurrent apnoea
Management:
- Exogenous surfactant administration
- Endotracheal intubation
- O2/other airway management strategies
- Caffeine administration
What problems may a pre-term neonate have with regards to their cardiovascular system?
How may this be managed?
- Hypotension
- Perfusion abnormalities
- PDA
Management:
- Inotropes
- Fluids
- Ibuprofen administration
What problems may a pre-term neonate have with regards to their neurological system?
How may this be managed?
- IVH
- Seizures
- Neurodevelopmental delay
- Cerebral palsy
Management
- CrUSS on babies <32 weeks
- Anti-epileptic drugs
What problems may a pre-term neonate have with regards to their GI system?
How may this be managed?
Immature gut causing feeding intolerance Necrotising enterocolitis (NEC)
Management: TPB NG feeds Abx Surgery with NEC
What problems may a pre-term neonate have with regards to their renal system?
How may this be managed?
Immature renal system
Management:
Close monitoring of fluid and electrolyte balance
Electrolytes supplements when indicated
What problems may a pre-term neonate have with regards to metabolic problems?
How may this be managed?
Jaundice
Hyperglycaemia
Hypoglycaemia
Inborn errors of metabolism
Management:
Phototherapy/exchange transfusion
Insulin infusion Glucose infusion
Baseline investigations (including Guthrie card)
What problems may a pre-term neonate have with regards to infection/immunity?
How may this be managed?
Sepsis
Increased risk of infection due to central lines and multiple procedures
Management:
- Septic screen
IV Abx
What problems may a pre-term neonate have with regards to their skin?
How may this be managed?
Immature skin barrier leading to increased insensible losses and increased risk of infection
Management:
Nursing in a warm, humid incubator
ANTT
What problems may a pre-term neonate have with regards to thermoregulation?
How may this be managed?
Immature thermoregulation
Management:
Nursing in a warm humid incubator, cot warmer, awareness of exposure whilst performing procedures and examination
What problems may a pre-term neonate have with regards to their eyes?
How may this be managed?
Reitonpathy of prematurity
Management:
Avoid excessive O2 exposure
Screen for retinopathy of prematurity
Laser if necessary
