Neonatology Flashcards
Definition of prematurity?
Before 37 weeks.
Extreme - <28 weeks
Very preterm - 28-32 weeks
Moderate to late preterm - 32-37 weeks
Causes of prematurity?
Multiple pregnancies
Infections - group B strep, UTI, vaginal infection, foetal/placental infection, pre-eclampsia, cervical incompetence, placental abruption, PPROM, placenta praaevia, chronic maternal conditions - DM, HTN, 40% have no identifiable cause.
Risk factors for prematurity?
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 DM and HTN.
Physical injury/trauma.
Investigations of prematurity?
Blood gas FBC - preterm infants at high risk of infection, thrombocytopenia and anaemia U&Es, CRP Blood culture Blood group, Direct Coombs Test/Direct Antiglobulin Test. Chest XR - respiratory distress AXR - assess signs of NEC. Crainal USS.
Management of prematurity?
Delivery of extreme preterm infant should be planned for hospital with tertiary level neonatal unit.
Administer course of antenatal steroids
Magnesium sulphate for neuroprotection to baby.
Resuscitation:
<23 weeks - should not be performed
23 - 23+6 - best interest of baby
24 - 24+6 - resus commenced unless baby thought to be severely compromised.
After 25 weeks - appropriate to resuscitate and start intensive care.
Long term respiratory complications of prematurity and management?
Respiratory distress syndrome
Surfactant deficient lung disease
Chronic lung disease/bronchopulmonary dysplasia
Recurrent apnoea
Surfactant administration, endotracheal intubation, mechanical ventilation.
CPAP, high flow oxygen, nasal cannula low flow oxygen, ambient incubator oxygen, caffeine administration.
Long term cardiovascular complications of prematurity and management?
Hypotension
Perfusion abnormalities
PDA
Inotropes
Fluid management
Ibuprofen
Ligation of PDA
Long term neurological complications of prematurity?
Intraventricular haemorrhage Seizures Post haemorrhage ventricular dilatation Neurodevelopmental delay Cerebral palsy
CrUSS
Regular head circumference measurements
Admin of AED
Follow up with neuro.
Long term gastrointestinal complications of prematurity?
Immature gut causing feed intolerance, necrotising enterocolitis (NEC).
TPN, NG feed, breast milk, abx, surgical review if NEC.
Long term renal/electrolyte complications of prematurity?
Immature renal function
Fluid and electrolyte balance monitoring. Catheterisation if indicated.
Long term metabolic complications of prematurity?
Jaundice
Hyperglycaemia
Hypoglycaemia
Inborn errors of metabolism
Phototherapy, exchange transfusion, insulin infusion, increase concentration or volume of glucose given via central IV access, doing heel-prick test.
Long term infection/immune complications of prematurity?
Sepsis
Increased risk of infection due to central lines and multiple procedures
Septic screen
IV abx
Long term skin complications of prematurity?
Immature skin barrier leading to increased insensible losses and increased risk of infection
Nursing in warm, humid incubator, aseptic non-touch technique during procedures.
Long term thermoregulation complications of prematurity?
Immature thermoregulation
Nursing in warm humid incubator, cot warmer, awareness of exposure whilst performing procedures and examinations.
Long term complications of eyes of prematurity?
Retinopathy of prematurity
Avoid excessive oxygen exposure.
Screening for retinopathy of prematurity by ophthalmology team, laser treatment if indicated.
When do anterior and posterior fontanelles close?
Anterior - 9-18 months
Posterior - 6-8 weeks
What are the key changes to respiratory system when child is born?
In utero, airways filled with amniotic fluid. Oligohydramnios can lead to small, underdeveloped lungs.
Amniotic fluid removed by squeezing of thorax during vaginal delivery.
There is also reduced production and increased absorption during labour and after birth.
Surfactant lines alveoli and reduces surface tension. Facilitates lung expansion and first breath.
Surfactant produced between 24 to 34 weeks gestation.
What are the key changes to CVS when baby is born?
Foetal circulation - pulmonary pressure exceeds systemic pressure causing right to left shunt through foramen vale and ductus arteriosus. Allows bypass of lungs.
At birth, these relationships change:
- systemic pressure increases with clamping of umbilical vessels
- pulmonary pressure reduced as lungs expand (oxygen increase and prostaglandin mediated vasodilation).
Foramen vale and ductus arteriosus close functionally after birth due to changes in pressure.
Key features of GI system at birth?
35 weeks gestation, develop coordination to latch on/suck from breast/bottle
Meconium usually passed at day 1
With effective feeding meconium is replaced by yellow stool by day 3-4
Immaturity of liver enzymes responsible for conjugation of bilirubin is responsible for physiological jaundice which can occur from day 2 of life.
Key features of GU system at birth?
Infant should void within 24 hours of life.
Often occurs during delivery so may go unnoticed.
Renal concentrating ability is reduced in neonates.
Key features of haem/immunity at birth?
Neonates have faetal Hb which has high affinity for oxygen.
Neonates have impaired neutrophil reserves, reduced phagocytosis, reduced complement, low IgG.
Maternal IgA crosses the placenta and are found in breast milk, providing some immune protection.
Key features of CNS at birth?
Myelination does not complete until 2 years of life.
Babies are born with primitive reflexes
Newborns sleep for 16-20 hours each day.
Apgar score factors?
Pulse Respiratory effort Colour Muscle tone Reflex/irritability
Apgar score ranges?
0-3 - very low
4-6 - moderately low
7-10 baby is in good state
Breast feeding in first few days of life?
Colostrum produced by breast in first few days, then replaced by milk.
Colostrum has high protein and Ig content.
Breast feeding intervals gradually lengthen from 2-3 hours to approx 4-hourly schedule.
What are contraindications to breast feeding?
What drugs are CI?
Galactosaemia
HIV
Aspirin Carbimazole Methotrexate Sulfonylureas Cytotoxic drugs Amiodarone Psychiatrics drugs - lithium, benzodiazepines Abx - ciprofloxacin, tetracycline, chloramphenicol, sulphonamides.
Advantages to breast feeding?
Reduced infection, atopy, constipation, maternal breast cancer, sudden infant death syndrome. Convenient, promotes bonding between mum and baby.
Disadvantages to breast-feeding?
Volume of intake uncertain.
Transmission of some drugs.
Nutrient deficiencies (vit D, vit K).
Failure to establish breast feeding results in emotional upset and guilt.
Difficulties with breastfeeding?
Sleepy baby
Difficulty latching
Cracked nipples
Poor milk supply
Problems with bottle feeding?
Incorrect reconstitution -> electrolyte abnormalities.
Over feeding -> reflux and vomiting
Inadequate sterilisation -> gastroenteritis.
Foetal causes of IUGR?
Symmetrical
Chromosomal disorders
Congenital infections
Maternal causes of IUGR?
Asymmetrical Pre-eclampsia Increased maternal age Smoking Multiple pregnancy
Risk of IUGR?
Death Hypoxia Hypothermia Hypoglycaemia (low fat and glycogen stores) Polycythaemia NEC.
Management of Group B strep
Antepartum maternal IV benzylpenicillin to women in preterm labour or with previous GBS pregnancy.
High vaginal swab offered at 35-37 weeks to detect GBS.
Women with pyrexia during labour given IV benzylpenicillin
At-risk neonates are given benzylpenicillin.
Risk factors for neonatal jaundice?
Gestational age <38 weeks (premature babies).
Small for date babies.
Previous sibling with neonatal jaundice requiring phototherapy.
Mothers intention to breastfeed exclusively.
Visible jaundice in first 24 hours of life.
What is physiological jaundice?
Normal rise in bilirubin, causing mild yellowing of skin and sclera from day 2-7 and usually resolves completely by 10 days.
Baby remains otherwise healthy and well.
Causes of neonatal jaundice?
First 24 hours - pathological
- excessive haemolysis - rhesus incompatibility, ABO incompatibility, G6PD deficiency, pyruvate kinase deficiency, hereditary spherocytosis.
2 days to 2 weeks:
- physiological
- breast milk jaundice
- UTI
- Excess haemolysis, bruising or polycythaemia
Prolonged jaundice >14 days - always investigate biliary atresia needs urgent surgery.
- uncongugated - breast milk jaundice, UTI, excess haemolysis
- conjugated - biliary atresia, neonatal hepatitis, alpha-1 antitrypsin deficiency.
Features of rhesus incompatibility?
Haemolysis, anaemia, jaundice
Severe cases - foetal hydrops and death.
Rhesus status now screened antenatally, and anti-D Ig given to rhesus neg mothers.
Features of ABO incompatibility?
Anaemia, jaundice, positive direct antiglobulin test (haemolysis). Less severe than rhesus incompatibility.
Features, investigations and management of biliary atresia?
Destruction or absence of extra hepatic biliary tree.
Rare but life-threatening, so much always investigate prolonged jaundice (urgent surgery).
Prolonged jaundice - dark urine, pale stools.
Failure to thrive as disease progresses due to:
- malabsorption
- enlargement of liver and spleen
Bleeding tendency might develop due to vitamin K deficiency.
Abdominal USS, liver biopsy, cholangiography.
Kasai surgical procedure - ideally <6 weeks.
Prognosis - often requires transplant by aged 20.