Neonatal Flashcards
3 definitions of a premature baby
Small for Gestational Age
Intrauterine Growth Restriction
Hypotrophy
2 types of hypotrophy in premature babies
Symmetric- all values the same
Asymmetric
Causes of prematurity
Maternal - smoking, pre-eclampsia/toxaemia
Foetal - Chromosomal (Edward’s), Infection (CMV)
Placental
Twin pregnancy
- Recipient and donor - receipient has circulation overload
Common problems in premature babies
Perinatal hypoxia Hypoglycaemia Hypothermia Polycythaemia Thrombocytopenia Gastrointestinal (feed, NEC)
Why is the gut more susceptible to ischaemia in premature babies?
Sympathetic compensation to vital organs
Blood flow to skin, gut and muscle implicated
What can happen if the gut wall becomes ischaemic in premature babies?
Perforation
Long term issues for premature babies
Hypertension
Reduced growth
Obesity
Ischaemic Heart Disease
What causes respiratory distress syndrome in the newborn>
Not enough surfactant
At what stage does a baby begin producing surfactant?
24-28 weeks of pregnancy
When might respiratory distress syndrome occur in babies who were delivered at term?
Mother is diabetic
Baby is underweight
Lungs not developed
Symptoms of Newborn Respiratory Distress Syndrome?
Cyanosed - blue lips, fingers, toes
Rapid, shallow breathing
Flaring nostrils
runting when breathing
Investigations for Newborn Respiratory Distress Syndrome
Physical examination
Bloods - exclude infection
Pulse oximetry
Chest x-ray
How will lungs of a premature baby with NRDS appear on x-ray?
Cloudy
Treatment for Newborn Respiratory Distress Syndrome
Surfactant
Early extubation
Non-invasive support
Minimal ventilation (low tidal, good inflation)
Complications of Newborn Respiratory Distress Syndrome
Pneumothorax
Bleeding
Developmental issues due to hypoxia - learning diffculties, difficulty with hearing, vision, movement problems
Bronchopulmonary dysplasia
Aetiology of bronchopulmonary dysplasia
Volume trauma in lungs leads to inflammatory changes
Scarring occurs from tissue repair
Scarring occurs from surfactant or steroids to treat NRDS
Causing atelectasis
What is atelectasis?
Loss of lung volume, failed expansion, (collapse)
Treatment of bronchopulmonary dysplasia?
Patience
Nutrients
Steroids
Treatment for apnoea/irregular breathing/desaturations?
Caffeine
N-CPAP
How is intraventricular haemorrhage prevented in premature babies?
Antenatal steroids
Treatment of intraventricular haemorrhage
Symptomatic
Drainage
What changes are seen at Day Of Life 7 in periventricular leukomalacia? (PVL)
Cystic changes
What DOL will show significant changes from DOL7 in periventricular leukomalacia (PVL)?
DOL21 -significantly worse changes
Cause of oedema in lungs in premature baby?
Patent Ductus Arteriosus
How can a patent ductus arteriosus give rise to fluid in the lungs?
Additional pulmonary circulation, over perfusion of lungs
Other complications of a patent ductus arteriosus
Reduced systemic circulation due to overperfusion of lungs leads to ischaemia
Worsening respiratory problems
Fluid retention ( low renal perfusion)
GI symptoms
How does necrotising enterocolitis occur (NEC)?
Inflammatory and ischaemic changes lead to a necrotic bowel leading to perforation
Treatment of necrotising enterocolitis?
Surgery
Antibiotics
Parenteral nutrition (through vein)
Definition of premature baby
Delivered before 37 weeks gestation
Outcomes of premature babies
1/3 will die
1/3 normal to mild disability
1/3 moderate to severe disability
At what week does the cardiovascular system develop in the foetus?
Towards end of 3rd week
At what week is a heartbeat present in the foetus?
4th week
Which days after fertilisation are critical for development of the foetus?
Days 20-50 after fertilisation
Through which vessel does the foetus receive oxygenated blood?
Umbilical vein - Ductus venosus
How does blood enter the Aorta in the foetus>
Foramen ovale to left atrium, to left ventricle to aorta
How does blood enter the pulmonary artery in the foetus?
Right ventricle, to pulmonary artery, via patent ductus arteriosus to aorta
What is the SaO2 in a foetal body?
60-70%
What is the function of the ductus arteriosus?
Protects lungs from circulatory overload
Allows the right ventricle to strengthen
Carries low oxygen saturated blood
Function of the ductus venosus?
Foetal blood vessel connecting umbilical vein to IVC
Carrie oxygenated blood
How is the blood flow regulated in the ductus venosus?
Via sphincter
What is the normal heart rate of a full term newborn?
120-160 beats per minute
Tachycardic > 160
Bradycardic <100
What is the normal respiratory rate of a full term newborn?
30-60 per min
Periodical breathing
What is the normal blood pressure of a full term newborn?
At 1 hour 70/44
At day One : 70 +/-9 over 42+/- 12 diastolic
Day Three : 77+/- 12, over 49 +/- 10 diastolic
Around which days are signs of physiological jaundice common?
DOL 2-3, disappear DOL 7-10 up to DOL 21 in preterm infants
What percentage of babies develop visible jaundice?
60% term
80% preterm
What is kernicterus?
High levels of bilirubin
Can cross BBB leading to irreversible changes
Treatment for physiological jaundice
Blue light
converts bilirubin to water soluble form - increasing bilirubin oxidation
3 features of increased fluid loss in the kidney in premature infants
Slower GFR
Reduced Na absorption
Decreased ability to concentrate/dilute urine
Reason for increased insensible water loss in premature infants
Immature skin
Breathing
At DOL 7, what percentage of previous production in the uterus is the production of red blood cells in the infant?
10%
What is the haemoglobin level normally at birth?
12-20 g/l
What is the haemoglobin by week 11 in the infant?
11.4 g/l
What is increasingly produced between week 10 and week 20 in the infant?
Erythropoeitin
What is the haemoglobin level by week 20?
12 g/l
3 causes of anaemia in prematurity
Reduced erythropoiesis
Infection
Blood letting
