Lecture 3 Part 1

Question 1

What is jaundice a symptom of?

Answer 1

High bilirubin levels in the blood

Question 2

What causes jaundice?

Answer 2

Accumulation of bilirubin in the skin and sclera, resulting in yellow discolouration

Question 3

What happens when there is too much bilirubin?

Answer 3

Orange-yellow pigment formed by the breakdown of haemoglobin

Question 4

Why is bilirubin needed?

Answer 4

It’s a normal catabolic pathway which is necessary for the clearance of waste products

Question 5

What percentage of term babies get hyperbilirubinaemia?

Answer 5

60%

Question 6

What percentage of preterm babies get hyperbilirubinaemia?

Answer 6

80%

Question 7

Explain the process of bilirubin creation

Answer 7

Reticuloendothelial cells maintain the red blood cells levels by destroying abnormal and old red blood cells by breaking it down into haem and globin groups.

Globin is further broken down into amino acids and recycled

Haem is further broken down into iron and biliverdin. The iron is recycled and the biliverdin is reduced to create unconjugated bilirubin

Question 8

Name the types of bilirubin and what they are also known as

Answer 8

Unconjugated - indirect

Conjugated - direct

Question 9

Explain the process where conjugated bilirubin is formed from unconjugated bilirubin

Answer 9

In the bloodstream, unconjugated bilirubin bins to albumin and is transported to the liver

In the liver, the enzyme GLUCURONYL TRANSFERASE adds GLUCURONIC ACID to unconjugated bilirubin and it’s converted to conjugated bilirubin

Conjugated bilirubin is water soluble and can be excreted into the duodenum in bile

Question 10

What is urobilinogen? What does it do?

Answer 10

A colourless byproduct of the breakdown of bilirubin in the intestines. Formed by gut bacteria on conjugated bilirubin.

Is it either reabsorbed into the bloodstream and excreted in urine as urobilin, giving urine its yellow colour, or it remains in the intestines and is converted to stercobilin, which gives stool its brown colour.

Monitoring urobilingoen levels in the urine can be helpful in diagnosing liver and blood disorders

Question 11

What percentage of urobilinogen is reabsorbed back into the bloodstream as part of the enterohepatic circulation?

Answer 11

20%

Question 12

Normal physiological jaundice occurs in all babies, when does it start to develop and how long does it last for?

Answer 12

Day 2 and lasts for around 2 weeks

Question 13

What is needed for normal jaundice not to have an impact on the baby?

Answer 13

A well established feeding

Question 14

If untreated, what can bilirubin do to the physiology?

Answer 14

Can cross the blood brain barrier

Damages the brain, spinal cord and central nervous system

Question 15

If untreated, what conditions can high levels of bilirubin cause?

Answer 15

Encephalopathy
Hearing loss
Seizures
Muscle spasms
Cerebral palsy - dystonic CP
learning disabilities

Question 16

What would be termed as pathological jaundice?

Answer 16

Any jaundice which presents under 24 hours of age, until proven otherwise and must be investigated promptly

Must be determined by a serum bilirubin

Question 17

What are the common causes of early jaundice?

Answer 17

Haemolysis - due to blood group incompatibilities or spherocytosis/elliptocyosis
Infection, TORCH or baterial infections
Normal variant, diagnosis of exclusion

History
Mums bloody group, antenatal history, family history - siblings with jaundice

Question 18

What would be classed as prolonged jaundice?

Answer 18

Persists:
After 2 weeks of life in a term baby
After 3 weeks of life in a preterm baby

Question 19

What is the biggest differential in elevated bilirubin?

Answer 19

Whether the bilirubin is unconjugated or whether the conjugated fraction is substantially increased , more than 25% of the total

Question 20

What are the causes of persistent unconjugated hyperbilirubinaemia?

Answer 20

Poor milk intake
Haemolysis
Infections- especially urinary tract infection
Hypothyroidism
Breast milk jaundice (diagnosis of exclusion, cessation of breast feeding is not advised

Question 21

What disease is persistent jaundice in unconjugated hyperbilirubinaemia the earliest sign for?

Answer 21

Hypothyroidism, babies are screened for this disease

Question 22

What jaundice is present in otherwise healthy babies? And why?

Answer 22

Breast milk jaundice
They have normal conjugated portions, normal full blood count and blood group, no sign of infection and Haemolysis
Reassurance and no further action needed

Question 23

What type of high levels of bilirubin is always abnormal?

Answer 23

Conjugated

Question 24

What diseases conjugated hyperbilirubinaemia be a sign of?

Answer 24

Hepatitis - can be caused be infection or by metabolic disorders
Biliary atresia

Question 25

What condition leads to elevated conjugated bilirubin as a result of bile duct obstruction? Elaborate

Answer 25

Biliary atresia - Fatal if not treated Infants usually have pale (clay coloured) stools and dark urine A surgical procedure called Kasai portoentrostomy is needed to treat, a diagnosis is needed 3 months prior of age Success of the surgery is directly related to age of operation, less than 10 weeks because there is a better chance of bile flow and reduced need for liver transplant

Question 26

After how many days of life is neonatal jaundice common?

Answer 26

14

Question 27

How rare is biliary atresia?

Answer 27

Occurs in 1 in 14 000 to 1 in 21000 births so very rare

Question 28

What campaign has the UK got for being alert for what condition of elevated conjugated bilirubin?

Answer 28

Yellow Alert Campaign for biliary atresia

Question 29

What is the treatment used for jaundice? How does it work?

Answer 29

Phototherapy is the use of light to lower the serum bilirubin levels It transforms bilirubin into water soluble without conjugation in the liver Light waves absorbed by the skin and the blood and unconjugated bilirubin molecules are converted into water soluble isomers, which are forms of bilirubin that can be easily excreted in the urine without the liver having to process them

Question 30

What light is the most effective for phototherapy?

Answer 30

Blue green light with a range of 460-490nm

Question 31

What is the phototherapy effectiveness dependent on?

Answer 31

Wavelength of the light Intensity of the light The distance between the light and the infant The amount of body area exposed to the light

Question 32

What phototherapy treatment for jaundice can be used? State the benefits and limitations

Answer 32

Fluorescent tubes Halogen spotlights These produce considerable heat which can be placed close to the infant Fibre optic blankets - limited exposure area LEDs - low heat production Gallium nitric LEDs - produce a high intensity wavelength light

Question 33

If phototherapy is used over a neonate, what is the safety checklist for it?

Answer 33

Overheat unit with main power cable attached Measuring device for radiating LED light Appropriate sized eye protection mask Cot Towels for boundaries

Question 34

List the pros and cons for the having phototherapy over the neonate

Answer 34

Pros: Height adjustable - can fit over any cot Can be tilted to allow full exposure Able to provide single, double and triple strength to babies without addition of further equipment Cons: Bulky - can be space consuming If height is adjusted by accident, the possibility of baby not recieving enough phototherapy Treatment must be stopped for feeding Need to separate baby and mother which can potentially affect the bonding

Question 35

The use of a billboat is another phototherapy technique, what is the checklist for this?

Answer 35

With mains power cable attached LED mattress Mattress cover Eye protection Cot

Question 36

For the billboat used for phototherapy, list the pros and cons for it

Answer 36

Pros: Greater exposure than blankets Used LEDs as opposed to UV or infrared which reduces the risk of skin damage/fluid loss Shut off function for elevated surface temperature - blocked air vent/increased ambient room temperature. Allows for the use of covers and blankets for heat and containment Cons: Heavy and buoy in comparison to biliblankets Cannot be used during feeding - hard surface, discomfort in comparison to overhead/biliblanket One size fits all - larger term babies, difficult to position ideally

Question 37

What is the checklist for a biliblanket?

Answer 37

Phototherapy unit Blanket pad attached to cable Soft disposable blanket cover Eye protecting mask Cot

Question 38

For a biliblanket used for phototherapy treatment, what are the pros and cons?

Answer 38

Pros: Babies on this piece of equipment can easily come out for S2S and feeding Different sized pads and blankets are available for varying gestational ages Can be offered out on loan to suitable patients whose parents wish to take their baby home on phototherapy and return to SCBU outpatient for review The pad design helps eliminate distance discrepancies Covers and blankets can be used over biliblankets Cons: Perhaps considered not as strong as overhead lights, therefore baby may require slightly lengthier treatments No battery so must always plug into mains power

Question 39

What are the phototherapy concerns? What problems may they cause?

Answer 39

Thermal environment imbalance - thermoregulation issues are rare with LEDs Maternal-infant interaction Retinal damage - eye protection

Question 40

Phototherapy treatment can cause complications also, state what these are

Answer 40

Increased water loss - diarrhoea, electrolyte imbalance Circadian rhythm disorder - sleep wake cycle disrupted Bronze baby syndrome side effect due to poor liver function and cholestatis