Neonatology Flashcards
What is a strawberry naevus?
Hemangioma
Disappears by 2 usually
What are milia?
Very very small pearly white papules on the face and forehead due to retained keratin in dermis
Resolves spontaneously
What is erythema toxicum?
AKA Neonatal urticaria
- Appears at 2-3 days
- Red blotches with central white pustule
- Found mainly on the trunk
- Lasts 24h
How does erythema toxicum differentiate to a septic rash?
Septic spots are smaller and non-mobile
Why is the skin of neonates more peely?
Less vernix (wax) that coats and moisturises their bodies
o Their skin will peel more
- Olive oil prevents skin from cracking
When are Petechial haemorrhage, facial cyanosis, subconjunctival haemorrhage seen?
- Related to slow birthing trauma of the face
What is neonatal sticky eye and how is it managed?
Due to unopened tear duct
Starts on day 3
Saline cleanse and spontaneous resolution
What is ophthalmia neonatal?
purulent discharge from the eye in neonates
may be due to bacterial infection (staphylococcal or streptococcal)
Topical chloramphenicol or neomycin
What are two differentials for sticky eye + lid swelling in first 48 hours
Gonococcal infection or chlamydia conjunctivis
How should a gonococcal eye infection in first 48 hours be managed? (5)
Swab, gram stain and culture urgent
Isolate
Hourly saline lavage
IM or IV ceftriazone
Treat parents
What are the complications of gonococcal eye disease?
Risks sight loss and disseminated disease
How does chlamydia conjunctivitis present differently to gonococcal?
More delayed presentation (at 1-2 weeks
How should chlamydia conjunctivitis be managed?
Regular lavage
Erythromycin PO for 14 days
Treat parents
What are the complications of chlamydia conjunctivits?
Pyloric stenosis
Chlamydia in lungs
What are the maternal advantages of breastfeeding?
↓ risk T2DM
↓ risk ovarian and breast cancer
Costs less
What are the immediate advantages of breastfeeding? (3)
Establishes a relationship/ emotional input from mother
Reduces infection risk e.g. GI, respiratory and otitis media
Protective against necrotising enterocolitis in preterm babies
What are the long term advantages of breastfeeding?
Reduces incidence of chronic conditions e.g diabetes, HTN, obesity
Essential nutrition for first 4-6 months
What are are 4 non-medical complications of breastfeeding?
Difficult to quantify weight gain
Failure = maternal emotional upset
If preterm, mother has to express until sucking reflex develops (30 weeks)
Multips has risk of not producing sufficient milk
What are 4 medical complications of breastfeeding?
Transmission of infection e.g. CMV, HIV
Transmission of drugs e.g. nicotine
Nutritional inadequacy after 6 months
Vitamin k deficiency as insufficient in breast milk
When do the suck reflex, swallow reflex and rooting reflex develop?
Suck reflex – 30 weeks gestation
Swallow reflex – 32-34 weeks gestation
Rooting reflex – 3 weeks, disappears at 4 months
Why is infection more common in preterm babies?
Maternal IgG is transferred during the 3rd trimester so more immunocompromised
↓ breastmilk = ↓ antibodies
Thymus hypertrophy doesn’t happen until after birth (makes T cells)
Prophylactic abx for sepsis
When is early onset sepsis defined?
Within 48 hours.
Anything over is late onset sepsis
What are the risk factors for early onset sepsis? (4)
P[P]ROM for >18 hours
Chorioamnionitis
Signs of maternal infection
Foetal distress in preterm lavour
What is the pathophysiology of early onset sepsis?
Transplacental Infection (maternal infection that has crossed the placenta)
Environmental Infection (bacterial infection from the birth canal that has entered the amniotic fluid which comes in direct contact with foetal lungs)
What are the most common causative organisms for transplacental infection?
Listeria monocytogenes
TORCH viruses
What are the most common causative organisms for environmental infection in early onset sepsis?
GBS
E. Coli
What is the pathophysiology of late onset sepsis?
Environmental Infection from central lines or endotracheal tubes
Spina bifida
What are the most common causative organisms for environmental infection in late onset sepsis?
Gram positive = Staphylococcus epidermidis/aureus or Enterococcus Faecalis
Gram negative = E. coli, Pseudomonas, Klebsiella
What is the definition of preterm birth?
Preterm birth as any baby born alive before 37 weeks of pregnancy are completed.
What are the definitions of extremely preterm, very preterm and moderate to late preterm?
Extremely preterm = <28 weeks
Very preterm = 28-32 weeks
Moderate to late preterm = 32-37 weeks
What are the CNS complications of preterm birth?
Intraventricular Haemorrhage
Retinopathy of prematurity
Poor suck and swallow
↑risk of adverse neurodevelopment outcomes/learning disabilities
What are the CVS complications of preterm birth?
↑ risk of PDA + CHD
What are the respiratory complications of preterm birth?
Neonatal Respiratory
Distress Syndrome
Chronic lung disease
Apnoea of prematurity
What are the GI complications of preterm birth?
Necrotising Enterocolitis
Jaundice
Poor milk tolerance
Give 3 other complications of preterm birth
Hypoglycaemia
Hypothermia
Immunocompromise
What is the effect of hypoglycaemia on preterm babies?
Defined as <2.6mmol/l
Preterm/ IUGR are more at risk due to poor glycogen stores and ↓ enzyme function
Jittery, drowsy, apnoea ⇢ seizures ⇢ permanent neurological damage if prolonged
Tx = regular monitoring of BMs, milk feed early and often. Can give IV dextrose if really bad
What is the effect of hypothermia on preterm babies?
Don’t temperature regulate if <1.5kg,
↑SA:Vol, not much subcutaneous fat
Keep warm in incubator, cover baby, heated mattress
↑ energy consumption to keep warm = hypocalcaemia, hypoglycaemia, hypoxia
What is intraventricular haemorrhage?
Haemorrhage into the ventricular system of the brain, usually happens spontaneously or due to trauma during birth
Usually occurs in first 72 hours of life
What are the signs and investigations for intraventricular haemorrhage?
Absent moro/drop reflex
Bulging fontanelles
Sleepy
Transfontanelle USS if <32weeks or known IUGR
What is the pathophysiology of retinopathy of prematurity?
Neonate has immature retinal vessels
Angiogenesis happens in response to an increase in O2
Giving high O2 = rapid and unstructured angiogenesis leading to an inefficient supply to the retina
Leads to a visual impairment
What is the management of retinopathy of prematurity?
weekly/fortnightly screening from ophthalmologist if premature or low birth weight
Laser photocoagulation/ anti-VEGF injections/ surgery if retinal detachment
What is the physiology of surfactant?
Surfactant is produced by type 2 pneumocytes and reduces the amount of surface tension within the alveoli by creating a barrier between air and water
Makes alveoli less likely to collapse and easier to inflate
When is surfactant produced? Which hormones inhibit and stimulate its production?
Surfactant is only produced AFTER 28 WEEKS
Cortisol, thyroxine and prolactin stimulate
Insulin inhibits
What is the pathophysiology of Respiratory Distress Syndrome?
If baby is born preterm then they have less surfactant so are more susceptible
Insufficient surfactant = ↑ surface tension in the alveoli = ↑ risk of collapse
Diabetic mothers are more prone to having babies with RDS as insulin inhibits surfactant production
How does RDS present in neonates?
At or within 4 hours of birth:
Tachypnoea - > 60 breaths per minute
Breathing difficulties → subcostal and sternal recessions + nasal flaring
Grunting on expiration → trying to create a positive airway pressure to maintain functional residual capacity!
Cyanosis if really severe
What are the bedside investigations for RDS in neonates and why?
Pulse oximetry
monitor pO2 and HR
Sats should be maintained at 91-95%
What are the blood tests for RDS in neonates and why?
Blood gases - Capillary or umbilical? Monitoring for acidosis (Respiratory or metabolic + hypoxia)
U&E - Electrolyte imbalances
Blood culture - Rule out sepsis
LFTs
BM
FBC
What imaging should be done for RDS in neonates and why?
CXR - changes
Echo - PDA
What is the management of RDS in neonates?
Oxygen therapy
Can give via high flow cannula or CPAP or mechanically (last resort)
Surfactant
Give steroids to mam if PROM between 28-32 weeks
Surfactant replacement therapy via endotracheal tube
Antibiotics until >3-5 days if blood cultures are negative
Small volume feeds via a tube once breathing is stabilised to stimulate gut development
General supportive therapy
What is the normal physiology of bilirubin metabolism?
Reticulocytes (RBC precursor) ⇢ Erythrocytes ⇢ Haem + Globin (macrophages in spleen and bone marrow)
Globin → Erythropoeisis
Haem ⇢
Iron → Erythropoeisis
In the liver = Unconjugated Bilirubin → Conjugated Bilirubin
In the terminal ileum = Conjugated bilirubin ⇢ Urobilogen → Stercobilin OR some is reabsorbed using bacterial enzymes from gut flora
What are the types of jaundice and how do they come about? Which type of bilirubin is associated?
Pre-hepatic
Unconjugated Bilirubin
Anything that ↑ rate of haemolysis e.g. haemaglobinopathies (sickle cell, thalassaemias, G6PD)
Hepatic
Conjugated Bilirubin
Builds up in blood due to ↓ efficiency of liver to break down haemoglobin
Post-hepatic
Conjugated Bilirubin - Bilirubin does not drain into the biliary system via bile
When is jaundice normal and not normal in a neonate?
First 24 hours = NOT NORMAL
24 hours - 14 days = NORMAL
14+ days = NOT NORMAL
Which type of jaundice is present in the first 24 hours and what are the causes?
Pre hepatic due to ↑ haemolysis
Sepsis via a congenital infection
Haemolytic Disease of the newborn (ABO incompatibility, Rhesus incompatibility)
Haemaglobinopathy e.g. spherocytosis, sickle cell, thalassaemia, G6PD
How does ABO incompatibility lead to haemolytic disease of the newborn?
MOther is blood group O
BA-By is blood group A or B
Blood antibodies are usually IgM so can’t cross the placenta but in this case they are IgG so can cross placenta and haemolyse foetal RBCs
How does ABO incompatibility present?
Severe jaundice that peaks in first 12-72 hours
Normal/slightly ↓ Hb
No hepatosplenomegaly
What are the foetal investigations for ABO incompatability?
Cord blood samples to find cause
Infection - TORCH screen
Hb (normal or slightly low)
Blood group
Direct Coombs test
LFTs
What is the management of ABO incompatibility?
Ventilation + high flow + PEEP
Drainage of severe fluid overload e.g. ascites/pleural effusion + IV furosemide if CCF + fluid limitation
Correction of anaemia
IM vitamin K for clotting
How does rhesus incompatibility lead to haemolytic disease of the newborn?
Rhesus negative (rr) mother and rhesus positive father (Rr) = Rhesus positive baby = baby is incompatible with mother
Blood mixes at birth and maternal immune system becomes sensitised i.e. maternal IgG production in first pregnancy
Problem for later pregnancies is that maternal IgG crosses the placenta causing haemolysis of foetal RBCs
How does rhesus incompatibility present?
Jaundice - early and more severe than in ABO incompatability + Kernicterus
Hepatospelnomegaly as liver trying to produce more RBCs and liver and spleen taking up more RBCs
Thrombocytopaenia/coagulopathys/hypoalbuminaemia - ↑RBC production at expense of albumin (oedema)
Anaemia → congestive cardiac failure → oedema
Hydrops fetalis
What are the maternal investigations for rhesus incompatibility?
Maternal blood group, Rhesus status
What are the foetal investigations for rhesus incompatibility?
Cord blood sampling/ foetal blood
↓ Hb levels, Rh+
What is the management of rhesus incompatibility?
High risk = intensive phototherapy + extra water
Manage coagulopathy
Daily folic acid for 6 months to ↑RBC
Check for anaemia every 1-2 weeks for 12 weeks - transfuse as packed red cells if Hb <7g/dl or symptomatic. Do audiology screening if transfuse
Why is jaundice physiological between 24hours and 14 days?
↑ Hb at birth so ↑ breakdown of RBCs (pre-hepatic)
Liver doesn’t fully mature until after 2 weeks (hepatic)
Lack of gut flora to reabsorb conjugated bilirubin/eliminate bile pigments (post-hepatic)
Could also be breast milk jaundice. Cause is unknown but normally resolves around 6 weeks
How does prolonged jaundice present?
Jaundice after 14 days
Chalky white stools and dark urine that stains the nappy
What are the causes of prolonged jaundice with ↑ unconjugated bilirubin?
Breast milk jaundice (unknown mechanism) - high unconjugated bilirubin
Infection
Hypothyroidism (↓rate of conjugation)
High GI obstruction e.g. pyloric stenosis
Haemolytic anaemia e.g. spherocytosis
What are the causes of prolonged jaundice with ↑ conjugated bilirubin?
Biliary atresia is concerning cause
Lumen of biliary tree is absent/blocked leading to an occlusion
Healthy term baby + persistent jaundice + hepatosplenomegaly + high conjugated bilirubin
Diagnose via cholangiogram and needs surgical management + assessment at specialist liver unit
What is a general bedside investigation to monitor jaundice?
Treatment threshold graph to interpret bilirubin levels (gestation specific as if ↓ gestation then ↓ level of bilirubin for neurological problems).
Has 2 lines: one for phototherapy, one for exchange transfusion and if on/above these lines then have to start the treatment
When do you measure serum and transcutaneous bilirubin levels?
Measure SERUM BILIRUBIN if in first 24 hours of life OR <35 weeks gestational age
Measure transcutaneously if after 24 hours or if >37 weeks GA
What are 6 blood tests to get the cause of jaundice in a neonate and why?
Conjugated and unconjugated bilirubin levels
Coombs/ direct antiglobulin test (+ve in antibody mediated anaemias)
FBC + blood film (anaemia + can visualise abnormalities)
TFTs (hypothyroidism is a cause of prolonged jaundice)
U&Es - dehydration?
LFTs - neonatal cirrhosis/damage
How does phototherapy work?
Light from the blue-green wave converts unconjugated bilirubin to a harmless substance that can be excreted in the urine
What are the complications of phototherapy?
Not harmful but disrupts care e.g. breastfeeding/cuddles with mum so only start if on or above the treatment line
Baby must be naked except nappy and have eyes covered as bright light is harmful
Also has a risk of temperature disturbance so monitor temperature + macular rash
Stop when bilirubin has fallen below the treatment line (measure serum bill regularly)
What is exchange transfusion?
Removal of foetal blood through arterial line/umbilical vein and replace with donor blood via peripheral line/umbilical vein
Done if unresponsive to phototherapy
What is Kernicterus, a complication of neonatal jaundice?
Encephalopathy due to deposition of unconjugated bilirubin in the basal ganglia and brainstem nuclei
Happens due to ↑ unconjugated bilirubin to a level that is greater than the albumin binding-capacity
Unconjugated bilirubin is fat soluble so can cross the blood brain barrier
How does Kernicterus present acutely?
Lethargic/Poor feeding
Irritable
Seizures
Hypertonia + lying with an arched back (opisthotonos)
How does chronic Kernicterus present?
Choreoathetoid Cerebral Palsy
Learning difficulties
Sensorineural deafness
What is necrotising enterocolitis?
Preterm bowel is vulnerable to ischaemic insult and bacterial invasion = tissue death
Occurs within first 2-3 weeks of feeding
What are the signs of necrotising enterocolitis?
Feeding intolerance
Distended abdomen
Bloody stools
What are the signs of necrotising enterocolitis on abdominal X-ray?
Rigler’s sign (gas in and out of bowel)
Dilated bowel loops
Bowel wall oedema
Pneumoperitoneum
Give 4 differentials for tachypnoea in the neonate
Acute Respiratory Distress Syndrome
Transient tachypnoea of the newborn (excess fluid in lungs. should resolve within 24hrs)
Meconium Aspiration (resp distress in the neonate born through meconium stained amniotic fluid which cannot be otherwise explained)
Bronchopulmonary dysplasia/Chronic lung disease (need for supplemental O2 28 days after birth)
What is Gastroschisis and an omphalocele? How can you differentiate between the two?
Defects of the abdominal wall that occur in utero and result in herniation of the gastric contents
There is a lack of a protective sac in gastroschisis which exposes the intestines to amniotic fluid in utero, leading to a thick inflammatory film
What is the management of omphalocele?
Caesarean to reduce risk of sac rupture
Staged repair (surgery)
What is the management of gastroschisis?
Vaginal delivery
Go to theatre asap after being born i.e. 4 hours
